Background
Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are two fluorinated compounds widely used in industry because of their useful chemical characteristics. They were identified ...as endocrine disruptors due to their ability to interfere with thyroid function. The resistance of PFOA and PFOS to environmental degradation, their bio-accumulation in food chains, and their long half-life raised concern in the scientific community, and several studies were performed with the aim to establish the real dangerousness of these compounds for the human health.
Purpose
The present review will focus on the effects of PFOA and PFOS on the thyroid gland taking into account in vitro experiments, animal studies, and human data. PFOS and PFOA reduce the circulating levels of thyroid hormones in diet-exposed animals, mainly by increasing their metabolic clearance rate.
Conclusions
An accumulation of PFOS and PFOA was documented in thyroid cells, and a cytotoxic effect was observed after exposure to extremely high concentrations of these compounds. In environmentally exposed communities and in the general population, the most consistent effect of exposure to PFOA, and to a less extent to PFOS, is the occurrence of hypothyroidism. Women and children appear to be more at risk of developing mild thyroid failure. Pregnant women with circulating thyroid antibodies might be at risk of developing subclinical hypothyroidism, mainly when exposed at high doses of PFOS. The relative risks for thyroid cancer in people exposed to PFOA and PFOS were low and based on a few cases. Moreover, there was no consistent finding across all or even most studies.
Purpose
Perfluorinated chemicals are widespread pollutants persistent in the environment with links to some major health issues. The two main compounds, perfluoro-octanoic acid (PFOA) and ...perfluoro-alkyl sulphonate (PFOS), were recently classified as carcinogenetic and thus their use has been restricted. Short-chain PFCs were recently developed as an alternative, but no data regarding the possible endocrine toxicities of these compounds are available. Aim of this study was to investigate whether short-chain PFCs could jeopardize thyroid cell viability and/or interfere with the functional effect TSH.
Methods
Fisher rat thyroid line-5 (FRTL-5) was treated with increasing concentrations of PFOA, PFOS, perfluorobutanesulfonic acid (PFBS), perfluorobutanoic acid (PFBA), pentafluoropropionic anhydride (PFPA), perfluoropentanoic acid (PFPeA) to evaluate modifications in cell viability and TSH-stimulated cAMP production.
Results
Neither long nor short-chain PFCs affected cell viability (apart from PFOS 100 µM), or interfered with cAMP production.
Conclusions
The results of the present study demonstrate for the first time that short-chain PFCs have no acute cytotoxic effect on thyroid cells in vitro and that cAMP production is not modulated by any of the tested PFCs.
Abstract
Background
Literature shows that music can reduce stress conditions. This pilot study investigated the effects of music listening on work-related stress and well-being in healthcare ...professionals.
Method
A total of 45 subjects were randomly assigned to three treatment groups: No Music, Individualized Music and Melomics-Health Listening. Music groups experienced a daily 30-min-playlist listening for 3 weeks at home. The Maugeri Stress Index-Revised (MASI-R) and the Psychological General Well-Being Index (PGWBI) were administered at baseline, after 3 weeks and after 7 weeks (follow-up). Longitudinal data were analyzed by means of a nested ANOVA model, testing the main effects of time and treatment and the interaction between them.
Results
MASI-R scores showed a positive trend in music groups and a worsening in the control group. Only the interaction time/treatment emerged as supporting a trend toward statistical significance (P = 0.07). PGWBI showed a stability in music groups and a clear decline in controls, without significant effects.
Conclusions
Results from the study support the need for a larger clinical trial: it is suggested that daily music listening could be implemented to reduce work-related stress and that the effects may be related, not only to individual musical preferences and familiarity, but also to specific music structures and parameters.
Purpose
Per- and poly-fluoroalkyl-substances (PFASs) are synthetic compounds that raised concern due to their potential adverse effects on human health. Long-chain PFAS were banned by government ...rules in many states, and thus, new emerging PFAS were recently introduced as substitutes. Among these, Perfluoro{acetic acid, 2-(5-methoxy-1,3-dioxolan-4-yl)oxy}, ammonium salt (C6O4) was recently introduced to produce a range of food contact articles and literature data about this compound are scanty. The aim of this study was to evaluate the in vitro effects of exposure to C6O4, compared with PFOA and PFOS on thyroid cells.
Methods
FRTL5 rat-thyroid cell lines and normal human thyroid cells (NHT) were incubated with increasing concentrations of C6O4 for 24, 48, 72, and 144 h to assess cell viability by WST-1. Cell viability was confirmed by AnnexinV/PI staining. Long-chain PFAS (PFOA and PFOS) were used at same concentrations as positive controls. The proliferation of cells exposed to C6O4, PFOA, and PFOS was measured by staining with crystal violet and evaluation of optical density after incubation with SDS. Changes in ROS production by FRTL5 and NHT after exposure to C6O4 at short (10, 20, and 30 min) and long-time points (24 h) were evaluated by cytofluorimetry.
Results
C6O4 exposure did not modify FRTL5 and NHT cell viability at any concentration and/or time points with no induction of necrosis/apoptosis. At difference, PFOS exposure reduced cell viability of FRTL5 while and NHT, while PFOA only in FRTL5. FRTL5 and NHT cell proliferation was reduced by incubation with by PFOA and PFOS, but not with C6O4. ROS production by NHT and FRTL5 cells was not modified after C6O4 exposure, at any time/concentration tested.
Conclusions
The present in vitro study constitutes the first evaluation of the potential adverse effects of the new emerging PFAS C6O4 in cultured rat and human thyroid cells, suggesting its safety for thyroid cells in vitro.
Musical sonification therapy is a new technique that can reinforce conventional rehabilitation treatments by increasing therapy intensity and engagement through challenging and motivating exercises. ...The aim of this paper is to evaluate the feasibility and validity of the SonicHand protocol, a new training and assessment method for the rehabilitation of hand function. The study was conducted in 15 healthy individuals and 15 stroke patients. The feasibility of implementation of the training protocol was tested in stroke patients only, who practiced a series of exercises concurrently to music sequences produced by specific movements. The assessment protocol evaluated hand motor performance during pronation/supination, wrist horizontal flexion/extension, and hand grasp without sonification. From hand position data, 15 quantitative parameters were computed evaluating mean velocity, movement smoothness, and angular excursions of hand/fingers. We validated this assessment in terms of its ability to discriminate between patients and healthy subjects, test-retest reliability and concurrent validity with the upper limb section of the Fugl-Meyer scale (FM), the functional independence measure (FIM), and the Box and Block Test (BBT). All patients showed a good understanding of the assigned tasks and were able to correctly execute the proposed training protocol, confirming its feasibility. A moderate-to-excellent intraclass correlation coefficient was found in 8/15 computed parameters. The moderate-to-strong correlation was found between the measured parameters and the clinical scales. The SonicHand training protocol is feasible and the assessment protocol showed good to excellent between-group discrimination ability, reliability, and concurrent validity, thus enabling the implementation of new personalized and motivating training programs employing sonification for the rehabilitation of hand function.
Bioactive glasses synthesized by the sol-gel technique possess many of the qualities associated with an ideal scaffold material for a bone graft substitute. In view of the potential clinical ...applications, we performed a detailed in vitro study of the biological reactivity of synthesized 58S bioactive glass containing-zinc, in terms of osteoblast morphology, proliferation, and deposition of a mineralized extracellular matrix (ECM). Human Sarcoma Osteoblast (SAOS-2) cells were used to i) assess cytotoxicity by lactate dehydrogenase (LDH) release and ii) evaluate the deposition of a calcified extracellular matrix by ELISA assay and quantitative RT-PCR (qRT-PCR). In comparison with pure silica and 58S, the 58S-Zn0.4 bioglass showed a significant increase in cellular proliferation and deposition of ECM components such as decorin, fibronectin, osteocalcin, osteonectin, osteopontin, type-I and -III collagens. Calcium deposition was significantly higher than on pure silica and 58S samples. Also Alkaline phosphatase (ALP) activity and its protein content was higher with respect to pure silica and 58S. qRT-PCR analysis revealed the up-regulation of type-I collagen, bone sialoprotein and osteopontin genes. All together these results demonstrate the cytocompatibility of 58S-Zn0.4 bioglass and its capability to promote osteoblast differentiation.
A brief review of urine analysis in studies of occupational exposure to volatile organic compounds and gases is provided. Analysis of exhaled breath for volatile compounds does not have a long ...history in occupational medicine. A number of studies has been undertaken since the 1980s, and the methods are well enough accepted to be put forward as biological equivalents of threshold limit values (TLVs) for some volatile organic compounds (VOCs) such as acetone; methanol; methyl ethyl ketone (MEK); methyl isobutyl ketone (MIBK); tetrahydrofurane; dichloromethane. In the last 20 years many scientific articles have shown that the urinary concentrations of unchanged solvents are correlated with environmental exposure and could be used for biological monitoring. The use of urine analysis of unchanged solvents in occupational applications is not yet widespread. Nonetheless, in the short time since its application, a number of important discoveries has been made, and the future appears bright for this branch of analysis. In this paper, the basic concepts and methodology of urine analysis are briefly presented with a critical revision of the literature on this matter. The excretion mechanisms of organic solvents in urine are discussed, with regard to biological variability, and the future directions of research are described.
OBJECTIVES To evaluate the contribution of traffic fumes to exposure to benzene in urban workers, an investigation on personal exposure to benzene in traffic police from the city of Rome was carried ...out. METHODS The study was performed from December 1998 to June 1999. Diffusive Radiello personal samplers were used to measure external exposures to benzene and alkyl benzenes during the workshift in 139 policemen who controlled medium to high traffic areas and in 63 office police. Moreover, as biomarkers of internal exposure to benzene, blood benzene, and urinary trans, trans-muconic and S-phenyl mercapturic acids were measured at the beginning and at the end of the workshift in 124 traffic police and 58 office police. RESULTS Time weighted average (TWA) exposure to benzene was consistently higher among traffic police than among indoor workers (geometric mean 6.8 and 3.5 μg/m3, respectively). Among the traffic police, the distribution of individual exposures was highly asymmetric, skewed toward higher values. Mean ambient benzene concentrations measured by municipal air monitoring stations during workshifts of traffic police were generally higher (geometric mean 12.6 μg/m3) and did not correlat with personal exposure values. In particular, no association was found between highest personal exposure scores and environmental benzene concentrations. Among the exposure biomarkers investigated, only blood benzene correlated slightly with on-shift exposure to benzene, but significant increases in both urinary trans, trans-muconic and S-phenylmercapturic acids were found in active smokers compared with non-smokers, irrespective of their job. CONCLUSION The exposure to traffic fumes during working activities in medium to high traffic areas in Rome may give a relatively greater contribution to personal exposure to benzene than indoor sources present in confined environments. Smoking significantly contributed to internal exposure to benzene in both indoor and outdoor workers.
In order to verify whether differentiation of adult stem cells toward bone tissue is promoted by high-frequency vibration (HFV), bone marrow stromal cells (BMSCs) were mechanically stimulated with ...HFV (30 Hz) for 45 minutes a day for 21 or 40 days. Cells were seeded in osteogenic medium, which enhances differentiation towards bone tissue. The effects of the mechanical treatment on differentiation were measured by Alizarin Red test, (q) real-time PCR, and protein content of the extracellular matrix. In addition, we analyzed the proliferation rate and apoptosis of BMSC subjected to mechanical stimulation. A strong increase in all parameters characterizing differentiation was observed. Deposition of calcium was almost double in the treated samples; the expression of genes involved in later differentiation was significantly increased and protein content was higher for all osteogenic proteins. Lastly, proliferation results indicated that stimulated BMSCs have a decreased growth rate in comparison with controls, but both treated and untreated cells do not enter the apoptosis process. These findings could reduce the gap between research and clinical application for bone substitutes derived from patient cells by improving the differentiation protocol for autologous cells and a further implant of the bone graft into the patient.
Titanium oxide is a heterogeneous catalyst whose efficient photoinduced activity, related to some of its allotropic forms, paved the way for its widespread technological use. Here, we offer a ...comparative analysis of the use of titanium oxide as coating for materials in biomedical devices. First, we introduce the photoinduced catalytic mechanisms of TiO2 and their action on biological environment and bacteria. Second, we overview the main physical and chemical technologies for structuring suitable TiO2 coatings on biomedical devices. We then present the approaches for in vitro characterization of these surfaces. Finally, we discuss the main aspects of TiO2 photoactivated antimicrobial activity on medical devices and limitations for these types of applications.
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