Determination of bisphenol A and bisphenol S concentrations and assessment of estrogen- and anti-androgen-like activities in thermal paper receipts from Brazil, France, and Spain.

Bisphenol A (BPA) is a high-production-volume chemical with endocrine disrupting properties commonly used as color developer in thermal paper. Concerns about the potential hazards of human BPA exposure have led to the increasing utilization of alternatives such as bisphenol S (BPS) and bisphenol F (BPF). This study was designed to assess: (i) BPA, BPS, and BPF concentrations in 112 thermal paper receipts from Brazil, France, and Spain by liquid chromatography coupled to mass spectrometry (LC-MS); and (ii) hormone-like activities of these receipts using two receptor-specific bioassays, the E-Screen for (anti-)estrogenicity and PALM luciferase assay for (anti-)androgenicity. BPA was present in 95.3% of receipts from Spain, 90.9% of those from Brazil, and 51.1% of those from France at concentrations up to 20.27 mg/g of paper. Only two samples from Brazil, two from Spain, and ten from France had a BPS concentration ranging from 6.46 to 13.29 mg/g; no BPA or BPS was detected in 27.7% of French samples. No BPF was detected in any receipt. Estrogenic activity was observed in all samples from Brazil and Spain and in 74.5% of those from France. Anti-androgenic activity was observed in > 90% of samples from Brazil and Spain and in 53.2% of those from France. Only 25.5% of French samples were negative for both estrogenic and anti-androgenic activity. Estrogenic and anti-androgenic activities per gram of paper were up to 1.411 µM estradiol (E2) equivalent units (E2eq) and up to 359.5 mM procymidone equivalent units (Proceq), respectively. BPA but not BPS concentrations were positively correlated with both estrogenic and anti-androgenic activities. BPA still dominates the thermal paper market in Brazil and Spain, and BPS appears to be one of the main alternatives in France. There is an urgent need to evaluate the safety of alternatives proposed to replace BPA as developer in thermal printing. The large proportion of samples with hormonal activity calls for the adoption of preventive measures.

Correction: Exposure to 1.8 GHz electromagnetic fields affects morphology, DNA-related Raman spectra and mitochondrial functions in human lympho-monocytes.

[This corrects the article DOI: 10.1371/journal.pone.0192894.].

Exposure to 1.8 GHz electromagnetic fields affects morphology, DNA-related Raman spectra and mitochondrial functions in human lympho-monocytes.

Blood is a fluid connective tissue of human body, where it plays vital functions for the nutrition, defense and well-being of the organism. When circulating in peripheral districts, it is exposed to some physical stresses coming from outside the human body, as electromagnetic fields (EMFs) which can cross the skin. Such fields may interact with biomolecules possibly inducing non thermal-mediated biological effects at the cellular level. In this study, the occurrence of biochemical/biological modifications in human peripheral blood lympho-monocytes exposed in a reverberation chamber for times ranging from 1 to 20 h to EMFs at 1.8 GHz frequency and 200 V/m electric field strength was investigated. Morphological analysis of adherent cells unveiled, in some of these, appearance of an enlarged and deformed shape after EMFs exposure. Raman spectra of the nuclear compartment of cells exposed to EMFs revealed the onset of biochemical modifications, mainly consisting in the reduction of the DNA backbone-linked vibrational modes. Respirometric measurements of mitochondrial activity in intact lympho-monocytes resulted in increase of the resting oxygen consumption rate after 20 h of exposure, which was coupled to a significant increase of the FoF1-ATP synthase-related oxygen consumption. Notably, at lower time-intervals of EMFs exposure (i.e. 5 and 12 h) a large increase of the proton leak-related respiration was observed which, however, recovered at control levels after 20 h exposure. Confocal microscopy analysis of the mitochondrial membrane potential supported the respiratory activities whereas no significant variations in the mitochondrial mass/morphology was observed in EMFs-exposed lympho-monocytes. Finally, altered redox homeostasis was shown in EMFs-exposed lympho-monocytes, which progressed differently in nucleated cellular subsets. This results suggest the occurrence of adaptive mechanisms put in action, likely via redox signaling, to compensate for early impairments of the oxidative phosphorylation system caused by exposure to EMFs. Overall the data presented warn for health safety of people involved in long-term exposure to electromagnetic fields, although further studies are required to pinpoint the leukocyte cellular subset(s) selectively targeted by the EMFs action and the mechanisms by which it is achieved.

To breathe or not to breathe: the haematopoietic stem/progenitor cells dilemma.

UNLABELLED: Adult haematopoietic stem/progenitor cells (HSPCs) constitute the lifespan reserve for the generation of all the cellular lineages in the blood. Although massive progress in identifying the cluster of master genes controlling self-renewal and multipotency has been achieved in the past decade, some aspects of the physiology of HSPCs still need to be clarified. In particular, there is growing interest in the metabolic profile of HSPCs in view of their emerging role as determinants of cell fate. Indeed, stem cells and progenitors have distinct metabolic profiles, and the transition from stem to progenitor cell corresponds to a critical metabolic change, from glycolysis to oxidative phosphorylation. In this review, we summarize evidence, reported in the literature and provided by our group, highlighting the peculiar ability of HSPCs to adapt their mitochondrial oxidative/bioenergetic metabolism to survive in the hypoxic microenvironment of the endoblastic niche and to exploit redox signalling in controlling the balance between quiescence versus active cycling and differentiation. Especial prominence is given to the interplay between hypoxia inducible factor-1, globins and NADPH oxidases in managing the mitochondrial dioxygen-related metabolism and biogenesis in HSPCs under different ambient conditions. A mechanistic model is proposed whereby 'mitochondrial differentiation' is a prerequisite in uncommitted stem cells, paving the way for growth/differentiation factor-dependent processes. Advancing the understanding of stem cell metabolism will, hopefully, help to (i) improve efforts to maintain, expand and manipulate HSPCs ex vivo and realize their potential therapeutic benefits in regenerative medicine; (ii) reprogramme somatic cells to generate stem cells; and (iii) eliminate, selectively, malignant stem cells. LINKED ARTICLES: This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8.

HCV infection induces mitochondrial bioenergetic unbalance: causes and effects.

Cells infected by the hepatitis C virus (HCV) are characterized by endoplasmic reticulum stress, deregulation of the calcium homeostasis and unbalance of the oxido-reduction state. In this context, mitochondrial dysfunction proved to be involved and is thought to contribute to the outcome of the HCV-related disease. Here, we propose a temporal sequence of events in the HCV-infected cell whereby the primary alteration consists of a release of Ca(2+) from the endoplasmic reticulum, followed by uptake into mitochondria. This causes successive mitochondrial alterations comprising generation of reactive oxygen and nitrogen species and impairment of the oxidative phosphorylation. A progressive adaptive response results in an enhancement of the glycolytic metabolism sustained by up-regulation of the hypoxia inducible factor. Pathogenetic implications of the model are discussed.

Toxoplasma gondii antibody profile in HIV-infected pregnant women and the risk of congenital toxoplasmosis.

The purpose of this study was to investigate the antibodies to Toxoplasma gondii in human immunodeficiency virus (HIV)-infected pregnant women and to determine the association between serological profile and the risk of congenital toxoplasmosis. The study, conducted in a public maternity ward from May 2002 to April 2005, included all HIV-infected women who delivered live infants during the 36 months, and, as a control group, all HIV-negative women that delivered live infants in the first 12 months of the study. Antibodies to T. gondii were detected in 1,624 of 2,421 HIV-negative women (67%; 95% confidence interval [CI] 65-69%) and in 121 of 168 HIV-infected patients (72%; 95% CI 65-79%). A total of 547 HIV-negative and 103 HIV-infected patients were tested at delivery and had positive T. gondii-specific IgG. In HIV-negative women, the median of the specific IgG concentration was 79 (interquartile range 38-160), and in HIV-infected patients, it was 283 (interquartile range 94-704) (P < 0.001). In the group of co-infected women, the only infant with congenital toxoplasmosis was born to a mother with acute toxoplasmosis infection acquired during pregnancy who did not have a high specific IgG concentration or a positive result for specific IgM. We concluded that high T. gondii-specific IgG values were much more frequent among HIV-infected pregnant women, but it did not translate into an increased risk of maternal-fetal transmission of toxoplasmosis.

Coexistence of mutations in PINK1 and mitochondrial DNA in early onset parkinsonism.

AIMS AND BACKGROUND: Various genes have been identified for monogenic disorders resembling Parkinson's disease. The products of some of these genes are associated with mitochondria and have been implicated in cellular protection against oxidative damage. In the present study we analysed fibroblasts from a patient carrying the homozygous mutation p.W437X in the PTEN-induced kinase 1 (PINK1), which manifested a very early onset parkinsonism. RESULTS: Patient's fibroblasts did not show variation in the mtDNA copy number or in the expression of the oxidative phosphorylation complexes. Sequence analysis of the patient's mtDNA presented two new missense mutations in the ND5 (m.12397A>G, p.T21A) and ND6 (m. 14319T>C, p.N119D) genes coding for two subunits of complex I. The two mutations were homoplasmic in both the patient and the patient's mother. Patient's fibroblasts resulted in enhanced constitutive production of the superoxide anion radical that was abrogated by inhibitor of the complex I. Moreover enzyme kinetic analysis of the NADH:ubiquinone oxidoreductase showed changes in the substrates affinity. CONCLUSION: To our knowledge, this is the first report showing co-segregation of a Parkinson's disease related nuclear gene mutation with mtDNA mutation(s). Our observation might shed light on the clinical heterogeneity of the hereditary cases of Parkinson's disease, highlighting the hitherto unappreciated impact of coexisting mtDNA mutations in determining the development and the clinical course of the disease.

Topological organization of NADPH-oxidase in haematopoietic stem cell membrane: preliminary study by fluorescence near-field optical microscopy.

The aim of this study was to characterize the local distribution and organization of the plasma membrane NADPH-oxidase (NOX) in human haematopoietic stem cell (HSC) by means of the fluorescence scanning near-field optical microscopy approach. The presence of NOX in haematopoietic stem cells is thought to have a functional role as O(2) sensor and/or as low-level reactive oxygen species (ROS) producer to be used as redox messenger for controlling cell growth and differentiation. Given the harmful potential of ROS, a fine-tuning of NOX activity is needed. The high resolution imaging of haematopoietic stem cell membrane obtained in this study combined with the immunodetection of NOX indicates for this the occurrence of a cluster-organized structure. These membrane 'rafts'-like micro-compartments may constitute localized protein aggregates whereby the assembly/activation of the NOX components are functionally integrated with upstream factors constituting signal-transduction platforms.

[Promoter effect induced by HgCl2 by studying the intercellular communication]. / Effetto promoter indoitto da HgCl2 attraverso lo studio della comunicazione intercellulare.

This work aims at assessing at molecular level the effect caused by the HgCl9 intercellular communication inhibition at non-cytotoxic doses. On the basis of our previous experiences, we exposed the human keratinocytes (HUKE) at 10 nM of HgCl2 for 24 hours Next, we estimated: a) the protein expression of connexines Cx43, Cx32 and Cx26 by western blotting; b) the amount of mRNA corresponding to the three connexines by semi-quantitative RT-PCR; and c) the production of reactive oxygen species in HgCl2 treated cells using a specific probe, i.e. DCF in confocal microscopy. Our study demonstrated a higher expression of the transcripts for Cx26, Cx32, Cx43, and a higher amount of proteins Cx43, Cx32 and Cx26, compared to the negative controls. Furthermore, we studied the effect of HgCl2 on the ROS production in keratinocytes, by the analysis in confocal microscopy carried out with the DCF, fit for marking the oxygen free radicals. In HgCl2 treated keratinocytes we obtained an increase of the ROS production compared to controls; and further the mitochondrions resulted the place of ROS production. The results of this study suggest that non-cytotoxic HgCl2 concentrations, might cause an unbalancing of the redox cellular state (ROS increased level), and we can assume that the activation of a redox signalling involves the inactivation of gap junctions.

Mitochondrial dysfunction in hepatitis C virus infection.

The mechanisms of liver injury in chronic hepatitis C virus (HCV) infection are poorly understood though HCV induces a state of hepatic oxidative stress that is more pronounced than that present in many other inflammatory diseases. This mini-review will focus on recent findings revealing an unexpected role of mitochondria in providing a central role in the innate immunity and in addition will illustrate the application of stably transfected human-derived cell lines, inducibly expressing the entire HCV open reading frame for in vitro studies on mitochondria. Results obtained by a comparative analysis of the respiratory chain complexes activities along with mitochondrial morpho-functional confocal microscopy imaging show a detrimental effect of HCV proteins on the cell oxidative metabolism with specific inhibition of complex I activity, decrease of mtDeltaPsi, increased production of reactive oxygen species. A possible de-regulation of calcium recycling between the endoplasmic reticulum and the mitochondrial network is discussed to provide new insights in the pathogenesis of hepatitis C.

Regulation by the cAMP cascade of oxygen free radical balance in mammalian cells.

A study is presented of the effect of the cAMP cascade on oxygen metabolism in mammalian cell cultures. Serum-starvation of the cell cultures resulted in depression of the forward NADH-ubiquinone oxidoreductase activity of complex I, decreased content of glutathione, and enhancement of the cellular level of H2O2. Depressed transcription of cytosolic Cu/Zn-SOD 1, mitochondrial glutathione peroxidase and catalase was also observed. Activation of the cAMP cascade reversed the depression of the activity of complex I and the accumulation of H2O2. The effect of cAMP involved the cAMP-dependent protein kinase.

Application of the compound probability density function for characterization of breast masses in ultrasound B scans.

The compound probability density function (pdf) is investigated for the ability of its parameters to classify masses in ultrasonic B scan breast images. Results of 198 images (29 malignant and 70 benign cases and two images per case) are reported and compared to the classification performance reported by us earlier in this journal. A new parameter, the speckle factor, calculated from the parameters of the compound pdf was explored to separate benign and malignant masses. The receiver operating characteristic curve for the parameter resulted in an A(z) value of 0.852. This parameter was combined with one of the parameters from our previous work, namely the ratio of the K distribution parameter at the site and away from the site. This combined parameter resulted in an A(z) value of 0.955. In conclusion, the parameters of the K distribution and the compound pdf may be useful in the classification of breast masses. These parameters can be calculated in an automated fashion. It should be possible to combine the results of the ultrasonic image analysis with those of traditional mammography, thereby increasing the accuracy of breast cancer diagnosis.

Classification of breast masses in ultrasonic B-mode images using a compounding technique in the Nakagami distribution domain.

Classification of masses in ultrasonic B-mode images of the breast tissue using "normalized" parameters of the Nakagami distribution was recently investigated. The technique, however, did not yield performances that were comparable to those of an experienced radiologist, and utilized only a single image for tissue characterization. Because radiologists commonly use two to four images of a mass for characterization, a similar procedure is developed here. A simple summation of the normalized Nakagami parameters from two different images of a mass is utilized for classification as benign or malignant. The performance of the normalized Nakagami parameters before and after the summation has been carried out through a receiver operating characteristic (ROC) study. The bootstrap procedure has been utilized to compute the mean and SD of the ROC area, A(z), obtained for each parameter. It has been observed that combining normalized Nakagami parameters from two images of the mass may help to improve classification performance over that from utilizing the parameters of just a single image. The performance of this automated parameter-based approach appears to match that of a trained radiologist.

Computer aided classification of masses in ultrasonic mammography.

Frequency compounding was recently investigated for computer aided classification of masses in ultrasonic B-mode images as benign or malignant. The classification was performed using the normalized parameters of the Nakagami distribution at a single region of interest at the site of the mass. A combination of normalized Nakagami parameters from two different images of a mass was undertaken to improve the performance of classification. Receiver operating characteristic (ROC) analysis showed that such an approach resulted in an area of 0.83 under the ROC curve. The aim of the work described in this paper is to see whether a feature describing the characteristic of the boundary can be extracted and combined with the Nakagami parameter to further improve the performance of classification. The combination of the features has been performed using a weighted summation. Results indicate a 10% improvement in specificity at a sensitivity of 96% after combining the information at the site and at the boundary. Moreover, the technique requires minimal clinical intervention and has a performance that reaches that of the trained radiologist. It is hence suggested that this technique may be utilized in practice to characterize breast masses.

Classification of ultrasonic B mode images of the breast using frequency diversity and Nakagami statistics.

The parameters of the Nakagami distribution have been utilized in the past to classify lesions in breast tissue as benign or malignant. To avoid the effect of operatorgain settings on the parameters of the Nakagami distribution, normalized parameters were utilized for the classification. The normalized parameter was defined as the ratio of the parameter at the site of the lesion to its average value over several regions away from the site. This technique, however, was very time consuming. In this paper, the application of frequency diversity and compounding is explored to achieve this normalization. Lesions are classified using these normalized parameters at the site. A receiver operating characteristic (ROC) analysis of the parameters of the Nakagami distribution has been conducted before and after compounding on a data set of 60 benign and 65 malignant lesions. The ROC results indicate that this technique can reasonably classify lesions in breast tissue as benign or malignant.

Tissue classification with generalized spectrum parameters.

This paper presents performance comparisons between breast tumor classifiers based on parameters from a conventional texture analysis (CTA) and the generalized spectrum (GS). The computations of GS-based parameters from radiofrequency (RF) ultrasonic scans and their relationship to underlying scatterer properties are described. Clinical experiments demonstrate classifier performances using 22 benign and 24 malignant breast mass regions taken from 40 patients. Linear classifiers based on parameters from the front edge, back edge and interior tumor regions are examined. Results show significantly better performances for GS-based classifiers, with improvements in empirical receiver operating characteristic (ROC) areas of greater than 10%. The ROC curves show GS-based classifiers achieving a 90% sensitivity level at 50% specificity when applied to the back-edge tumor regions, an 80% sensitivity level at 65% specificity when applied to the front-edge tumor regions, and a 100% sensitivity level at 45% specificity when applied to the interior tumor regions.

Imaging of the patient with silicone gel breast implants.

There are two reasons for radiologic evaluation of the augmented breast. Because women with implants are at the same risk for breast cancer as other women, imaging is performed to screen for cancer or to work up clinical abnormalities. Additionally, imaging allows assessment of implant integrity. The various methods for imaging implants and breast tissue in the augmented patient are discussed. Imaging findings suggestive of silicone gel implant rupture are presented.

On modeling biomedical ultrasound RF echoes using a power-law shot-noise model.

We propose a new model for the RF ultrasound echo, namely the power-law shot-noise process. Based on this model, the in-phase and quadrature components of the echo are shown to exhibit 1/f beta-type spectral behavior, in a sense that is defined in the paper. The envelope also exhibits this type of spectral behavior, but with a different exponent. This result explains the experimental observations by other researchers of the power-law trend of the RF echo spectrum. Although the shot-noise model has been used in the past for modeling the RF echo, this is the first time that a power-law impulse response filter is used and that the resulting 1/f beta-type spectral behavior of the RF echo has been investigated. The model parameters are linked to tissue characteristics, such as scatterer density and attenuation; thus, they have the potential to be used as tissue characterization features. The validity of the proposed model is tested based on a database of 100 clinical ultrasound images of the breast.

The cryoglobulins: an overview.

Cryoglobulins are cold-precipitable immunoglobulins associated with a number of infectious, autoimmune and neoplastic disorders. Their appearance along with rheumatoid factor (RF) can be considered a normal event in the clearance of immune complexes and rarely produces any symptoms. The association between hepatitis C virus (HCV) and mixed cryoglobulinemia (MC) has been rendered evident since the recognition of serological markers of HCV infection. There is thus every reason to suppose that direct or indirect involvement of B cells on the part of the HCV results in their persistent stimulation, clonal expansion and release of molecules with RF activity. The formation of RF/IgG immune complexes is the key pathogenetic mechanism. The close correlation between HCV infection and MC also throws new light on the interpretation of autoimmune phenomena in the course of viral infection and on the close link between autoimmune diseases and lymphoproliferative disorders. The higher risk of non-Hodgkin's lymphoma (NHL) displayed by HCV positive subjects, especially in the Mediterranean basin, suggests that the HCV's chronic lymphoproliferative drive may progress towards frank lymphoid neoplasia. The presence of MC does not represent an in situ or 'occult' NHL, because recent evidences indicate that none of the clones interpreted as predominant displays the molecular features of a true neoplastic process. The cryoglobulinemic syndrome is probably the consequence of pathogenic noxae that act upon the immune system of a host in which regulation of the peripheral T cell response appears to be in some way altered.