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The concentrations and comparisons of total and available metals Cd, Cr, Ni, Pb and the metalloid As were examined in two adjacent acid forest soils in Greece under oak and beech together with the dependency of their availability. It was found that the soil in the beech plot had higher concentrations of total elements with the exception of the litter layer (L) where most metals did not differ. It is probable that the parent material of the beech soil contained some metamorphic mafic material. The surface soils for both stands were moderately enriched with Pb, Cd and As, whereas for Cr and Ni the enrichment was minimal. The concentrations of available elements (extracted with DTPA) were higher in the beech soil. The availability of most metals was affected by the pH, the organic C, the ratio of C/N and the total concentration of the metals. Through a Principal Component Analysis (PCA) analysis, it was found that 63-75% of the concentrations variance of the available metals was explained. The percentages of available metals with regard to their total concentrations in soils were higher in the beech plot in the FH layer but in the mineral layers, they did not differ apart from Pb. The concentrations of the metals in the leaves of both species in three consecutive years did not differ with the exception of Cd, the concentration of which was higher in the beech leaves. © 2022 Global NEST Printed in Greece. All rights reserved.

Background: Hypomethylating agents have altered the prognosis of myelodysplastic syndrome (MDS) so that long-term survival is now a feasible treatment goal. Patients and Methods: We analyzed data from patients with MDS treated with 5-azacytidine recorded in the Hellenic 5-azacytidine registry. We divided patients, on the basis of their survival after 5-azacytidine initiation (OST), in groups of long-term survivors (Q3 and P90 group with OST above the third quartile and the 90th percentile of the whole group, respectively) and short-term survivors comprising the remaining patients, and compared the characteristics between the groups. The study included 626 patients, 157 in the Q3 group and 63 in the P90 group. Results: Categorization per the International Prognostic Scoring System (IPSS), revised IPSS (IPSS-R), and World Health Organization–based prognostic scoring system (WPSS) was found to predict long-term survival, while multivariate analysis revealed that response to 5-azacytidine was the strongest predictor of long-term survival. Nevertheless, patients with hematologic improvement (HI) and stable disease (SD) were equally distributed in the groups of short- and long-term survival. Conclusion: SD should not be considered a poor treatment response and should not be grouped with failure, while HI offers similar prognosis to SD and thus should not be grouped with complete and partial remission. Patients with SD should continue treatment with 5-azacytidine. The prognosis of myelodysplastic syndrome (MDS) has changed since the introduction of hypomethylating agents that offer the potential for long-term survival. We studied the characteristics of long-term survival in a cohort of 626 patients with MDS treated with 5-azacytidine; response was found to be the single most important predictive factor of long-term survival, while stable disease (SD) and hematologic improvement were equally distributed in the groups with long- and short-term survival. Achieving SD has prognostic significance, and SD should not be grouped with treatment failure. © 2019 Elsevier Inc.

The clinical significance of pleural effusions (PLEs) in the setting of acute pericarditis remains poorly investigated. We sought to identify predictive factors for PLEs and their association with the short- and long-term prognosis of patients with acute pericarditis. We enrolled 177 patients hospitalized with a first episode of acute pericarditis. In all cases an extensive clinical, biochemical, and diagnostic work-up to detect PLEs and establish etiological diagnosis was performed. All patients included were prospectively followed for a maximum of 18 months (median 12, range 1–18) and complications were recorded. PLEs were detected in n = 94 cases (53.1% of the cohort; bilateral 53.2%, left-sided 28.7%, right-sided 18.1%) and were strongly associated with c-reactive protein (CRP) levels at admission (rho = 0.328, p < 0.001). In multivariate logistic regression, independent predictors for PLEs were female gender (OR = 2.46, 95% CI 1.03–5.83), age (per 1-year increment OR = 1.030, 95% CI 1.005–1.056), CRP levels (per 1 mg/L increment OR = 1.012, 95% CI 1.006–1.019) and size of pericardial effusion (per 1 cm increment, OR = 1.899, 95% CI 1.228–2.935). Bilateral PLEs were associated with increased risk for in-hospital cardiac tamponade (OR = 7.52, 95% CI 2.16–26.21). There was no association of PLEs with new onset atrial fibrillation or pericarditis recurrence during long-term follow-up (χ2 = 0.003, p = 0.958). We conclude that PLEs are common in patients hospitalized with a first episode of acute pericarditis. They are related to the intensity of inflammatory reaction, and they should not be considered necessarily as a marker of secondary etiology. Bilateral PLEs are associated with increased risk of in-hospital cardiac tamponade, but do not affect the long-term risk of pericarditis recurrence. © 2019, Società Italiana di Medicina Interna (SIMI).

Poly (ADP-ribose) polymerase 1 (PARP1) is a nuclear enzyme that participates in the DNA repair of malignant cells, with various consequences on their survival. We have recently shown that PARP1 mRNA levels in the bone marrow of patients with myelodysplastic syndrome (MDS) are correlated to prognosis. To evaluate PARP1 as a biomarker of response to 5-azacytidine in patients with MDS, we measured PARP1 mRNA levels by a quantitative real-time PCR in diagnostic bone marrow samples of 77 patients with MDS treated with 5-azacytidine. Patients with higher PARP1 mRNA levels had a better response to 5-azacytidine per the IWG criteria (p = 0.006) and a longer median survival after 5-azacytidine initiation (p = 0.033). Multivariate analysis revealed that PARP1 mRNA level was the only factor affecting response to treatment and survival after treatment with 5-azacytidine. A next-generation sequencing for 40 genes of interest in MDS and quantification of the methylation levels of the PARP1 promoter were also carried out in a subset of samples (16 and 18 samples respectively). It is the first time that a single, easily measurable biomarker shows a clear correlation with response to treatment and survival in a patient population consisting of previously untreated patients with MDS homogeneously treated with 5-azacytidine. The fact that PARP1 is also a treatment target in several malignancies underscores the importance of our finding for the potential use of PARP1 inhibitors in MDS. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.

The aim of this paper is to provide an experimental examination of the application of linear system identification techniques in the design of linear model-based controllers for systems suffering nonlinear distortions. The study is conducted on an analog electrical circuit, which simulates a nonlinear mechanical resonating system. Parametric linear models are estimated from measurements taken using random-phase multisines. Furthermore, a full nonlinear model is estimated for the system. Initially, the estimated linear models and the nonlinear model are compared in terms of their performance in simulating the system dynamics. This is followed by the design of linear optimal controllers for the system based on the different models, and the performance obtained from the controllers based on the nonlinear model is set as the benchmark. It is shown that although the performance of the linear models estimated from the random multisine measurements is poor in terms of the simulation error when compared to that of the nonlinear model, it closely matches the performance of the nonlinear model in terms of controller design

The performance of a time-resolved fluorescence immunoassay (TRFIA) for detection of treponemal IgG from oral fluid specimens has been assessed in a predominantly HIV-infected population. Serological investigation is the method of choice for confirming clinical suspicion of syphilis; however, in the primary stage of disease, direct detection of treponemes in lesion fluid or Treponema pallidum DNA is recommended because of the reduced sensitivity of serological tests. There may be occasions when blood for serological investigation is difficult to obtain due to individual patient preference or logistical necessity to improve participation in screening initiatives, particularly in outreach situations. Collection of oral fluid for detection of treponemal antibody may prove an attractive alternative and, with this in mind, an oral fluid assay for detection of treponemal IgG was developed. Time-resolved fluorescence was used to detect treponemal IgG extracted from commercially available oral fluid collection devices. Paired serum and saliva samples were obtained from 210 individuals, 101 of whom were diagnosed with syphilis on the grounds of medical examination confirmed by serological testing. Oral fluid specimens from 14 subjects were rejected because they contained insufficient control antibody or were inhibitory. The population tested was predominantly men who have sex with men, many of whom were HIV infected. The overall sensitivity and specificity of the oral fluid assay was 95.8 and 86.1%, respectively, based on the 5th percentile of the positive results, and 93.7 and 91.1%, respectively, based on a cutoff derived by mixture model analysis. For individuals with primary syphilis, the optimum sensitivity of the oral fluid assay was 87.5%, whereas in those with disease classified as secondary syphilis and early latent syphilis, the sensitivity of the oral fluid assay was 100 and 94.7%, respectively. The oral fluid assay is a useful alternative to serological testing in certain situations, and further development of this technology to enable detection of treponemal IgM should increase its sensitivity for detecting cases of primary syphilis.

A frequency domain analysis of the influence of nonlinear distortions on linear frequency response function measurements performed using multisine test signals is presented in this paper. The aim is to provide a closer insight into the mechanisms at work when multisine signals are subjected to static power-series nonlinearities. Emphasis is given to the behavior of a class of nonlinear distortions, termed Type II contributions, when different types of multisine signals are applied to a cubic, fifth-, seventh-, and ninth-order static nonlinear element. The original results presented in this paper are a development of work conducted by the current authors as well as other authors in this area.

This paper examines the output properties of static power-series nonlinearities driven by periodic multiharmonic signals with emphasis given to their effect on linear frequency response function (FRF) measurements. The analysis is based on the classification of nonlinear distortions into harmonic and interharmonic contributions. The properties of harmonic contributions are examined in detail and explicit formulae are derived, by which the number of harmonic contributions generated at the test frequencies can be calculated for odd-order nonlinearities up to, and including, the ninth order. Although an analytic solution for any odd-order nonlinearity is still under investigation, a heuristic methodology is developed that solves this problem. It is shown that the derived formulae provide a useful tool in the examination of the behavior of FRF measurements in the presence of nonlinear distortions. Based on these formulae, different approaches in classifying nonlinear distortions are then compared with respect to their suitability in assessing the influence of system nonlinearities on linear FRF measurements.

When measuring the best linear approximation of systems suffering nonlinear distortions, a specific class of periodic multiharmonic signals is normally used. These are signals with uniformly distributed random phases, termed random phase multisines. In this paper, it is shown that measurements of the best linear approximation of nonlinear systems can also be obtained by using a special type of low crest factor multisines. These signals are compared to random phase multisines and their properties are analyzed in detail.

This paper examines the minimization of the signal crest factor using a frequency-domain method. This method is based on the observation that low crest factor signals possess properties that reduce the effect of system nonlinearities. The main idea of this method is that instead of setting the signal crest factor as the cost function to be minimized, multisine signals are designed with their harmonic phases selected to minimize the distortion introduced by a cubic nonlinearity on the measurement of a frequency response function. The resulting signals are compared with other types of low crest factor signals. It is found that the method does not produce the lowest possible crest factors but that the signals do minimize the nonlinear distortion introduced by a cubic nonlinearity, while possessing a low crest factor. The signals are thus termed minimum distortion multisines.

The aim of the study presented in this paper is to provide an experimental comparison between best linear approximation models and nonlinear models estimated for systems suffering nonlinear distortions. This is illustrated on a nonlinear mechanical resonating system. Parametric best linear approximation models are estimated from frequency response function measurements using random phase multisines. A full nonlinear model is also estimated for the system. The two types of models are then compared in terms of their performance in simulating the system and also when used as a basis for optimal controller design for the system. It is shown that in the presence of nonlinear distortions the choice between the two model types will depend on the intended use of the model.

A frequency domain analysis of the influence of nonlinear distortions on frequency response functions estimated using multisine test signals is presented in this paper. The aim is to illustrate the mechanisms at work when multisine signals are subjected to static nonlinearities. Particular emphasis is given to the behavior of a class of nonlinear distortions termed Type II contributions. The results obtained in this paper are a development of work conducted by the current authors as well as other authors in this field.

New insights on the frequency-domain output properties of nonlinear systems driven by multiharmonic signals will be discussed in this paper. These are based on a detailed analysis of the mechanisms at work on the generation of a class of nonlinear distortions, termed harmonic components. This leads to the derivation of formulae to calculate the number of harmonic components generated by any order of nonlinearity at the excitation frequencies during frequency response function measurements. Based on these formulae the classification of nonlinear distortions in harmonic and interharmonic components is compared against other methodologies on the classification of nonlinear distortions.

A new method for estimating the highest significant order of nonlinearity of Volterra type systems is presented. The method is based on the use of multisine signals and the possibility of testing the system at three different amplitudes. The performance of the proposed method is demonstrated in simulation and it is shown that it is possible to estimate the highest order of nonlinearity of Volterra type systems very accurately. The method can be used to provide essential prior knowledge about the nonlinearity and thus aid the accurate representation of the system under test.

Genetic alterations of the p53 tumor suppressor protein are the most frequent molecular events in human carcinogenesis. For as yet unknown reasons, mutant p53 often acts as an immunogen for autoantibody generation. These autoantibodies can be detected in the serum of cancer patients. The presence of such antibodies has been identified in a subset of patients with ovarian carcinoma, but their clinical significance has not been investigated.Serum samples from patients with ovarian carcinoma were quantitatively analyzed for the presence of p53 autoantibodies with a time-resolved immunofluorometric procedure. Tumor p53 overexpression was assessed by immunohistochemical analysis of tissue sections. Kaplan-Meier survival curves were calculated for p53 antibody positive and negative patients, and the Cox model was used to evaluate the strength of the associations between the presence of serum p53 antibodies and cancer relapse or death, and also between the presence of such antibodies and other clinicopathologic features.p53 antibodies were detected in the serum of 41 of 174 patients with ovarian carcinoma (24%). Antibody levels ranged from a few hundred to 9 x 10(6) arbitrary Units/L, and fluctuated during the course of the disease. p53 antibody positive patients tended to have tumors overexpressing p53, but the association between the two parameters was not statistically significant (P = 0.13). There was also no association between the presence of p53 antibodies and clinical stage, tumor histologic type, or overall patient survival. However, these antibodies were more frequently present in patients older than 50 years (P = 0.001), in patients with moderately or poorly differentiated tumors (P = 0.001), and in patients who received chemotherapy (P = 0.015), and who suffered relapse after surgery (P = 0.018). In univariate analysis, p53 antibody positive patients were at an increased risk for relapse but not death. In multivariate analysis, the differences in disease free and overall survival between patients who were p53 antibody positive or negative were not statistically significant.p53 autoantibodies are found frequently in the serum of patients with ovarian carcinoma. The presence of such autoantibodies was associated with older patient age, more aggressive tumors, and reduced patient disease free survival. In multivariate analysis the prognostic value of p53 autoantibodies was not statistically significant.

The aim of this article is to describe trends in infectious syphilis in the UK, and specifically the epidemiology of the London syphilis outbreak, the largest in the UK to date. Analysis of routine surveillance data from genitourinary medicine (GUM) clinics was performed as well as data collection through enhanced surveillance systems. There have been substantial increases in diagnoses of infectious syphilis between 1998 and 2003, with a 25-fold increase seen in men who have sex with men (MSM) (from 43 to 1028 diagnoses); 6-fold (138 to 860) in heterosexual men and 3-fold (112 to 338) in women. The national rise in syphilis was driven by a series of local outbreaks, the first of which occurred in 1997. To date, 1910 cases have been reported in the London outbreak, first detected in April 2001. High rates of HIV co-infection were seen among MSM, with MSM likely to be of white ethnicity and born in the UK. In contrast, heterosexuals were more likely to be of black ethnicity and born outside the UK. Most syphilis infections were acquired in London. MSM bear the brunt of the national resurgence in infectious syphilis. Substantial rises in male heterosexual cases has resulted in a divergence between male heterosexual and female cases, which now requires further investigation.