Impact of tire debris on in vitro and in vivo systems

BACKGROUND: It is estimated that over 80% of respirable particulate matter (PM(10)) in cities comes from road transport and that tire and brake wear are responsible for the 3–7% emission of it. Data on the indicators of environmental impact of tire debris (TD), originated from the tire abrasion on roads, are extremely scarce, even though TD contains chemicals (zinc and organic compounds) which can be released in the environment. METHODS: TD particle morphology was analysed with SEM, TEM and FIB instruments. TD eluates and TD organic extracts were tested at dilution series on human cell lines and Xenopus laevis embryos. 50 and 100 g/L TD were used for the eluates obtained after 24 h at pH 3 and the quantity of zinc present was measured with a ICP-AES. Eluates diluted to 1%, 10%, 50% in culture media and undiluted were used on X. laevis embryos in the FETAX test. HepG2 cells were exposed for 24 h to 0.05 – 50 μg/ml of zinc salt while A549 cells were exposed for 24, 48 and 72 h to 10, 50, 60, or 75 μg/ml of TD extract. X. laevis embryos were exposed to 50, 80, 100, or 120 μg/ml TD extract. RESULTS: The solution of undiluted 50 g/L TD produced 80.2% mortality (p < 0.01) in X. laevis embryos and this toxic effect was three times greater than that produced by 100 g/L TD. Zn accumulation in HepG2 cells was evident after 4 h exposure. A549 cells exposed to TD organic extract for 72 h presented a modified morphology, a decrease in cell proliferation and an increase in DNA damage as shown by comet assay. The dose 80 μg/ml of TD extract produced 14.6% mortality in X. laevis embryos and 15.9% mortality at 120 μg/ml. Treatment with 80, 100, or 120 μg/ml TD organic extract increased from 14.8% to 37.8% malformed larvae percentages compared to 5.6% in the control. CONCLUSION: Since the amount of Zn leached from TD is related to pH, aggregation of particles and elution process, the quantity of TD present in the environment has to be taken into account. Moreover the atmospheric conditions, which may deeply influence the particle properties, have to be considered. The TD organic fraction was toxic for cells and organisms. Thus, because of its chemical components, TD may have a potential environmental impact and has to be further investigated

Human fibrinogen and thrombin patch for extraluminal protection of intestinal anastomosis

AbstractIn spite of recent advances regarding equipment and surgical techniques in colorectal surgery, rates of anastomotic dehiscence (AD) have remained stable throughout the years. The development of products to protect anastomosis aiming the reduction of AD rates has shown to be promising. Human fibrinogen and thrombin patch (HFTP Tachosil®) have been used in experimental studies in animals and small case series in humans, with promising results. In this study, the authors describe the technique of HFTP use in details, aiming the protection of colorectal anastomosis, and retrospectively demonstrate the preliminary results in a pilot case series. HFTP was used in 4 patients submitted to conventional surgery. The procedures performed were: left colon resection, segmental colectomy (both for colorectal cancer), enteral anastomosis for fistula closure and right ileocolectomy. Anastomotic healing and absence of complications were observed in 3 patients, and the patient submitted to right ileocolectomy developed AD and died after reoperation. The use of HFTP is safe and can be indicated in selected cases. However, AD can occur even after the use of this strategy. Randomized controlled trials with larger samples of patients are needed in order to properly define the real benefits of this strategy in dehiscence preventio

Skeletal muscle characteristics and motor performance after 2-year growth hormone treatment in adults with prader-willi syndrome.

Context:In adults with Prader-Willi syndrome (PWS), abnormal body composition with decreased lean body mass and skeletal muscle (SM) volume has been related to altered GH secretion and may possibly contribute to greatly reduced motor capacity.Objective:The scope of the study was to test the hypothesis that GH treatment has favorable effects on SM characteristics and motor performance in adults with PWS.Design, Setting, and Participants:Fifteen obese PWS subjects (nine males and six females; age range, 19–35 y; body mass index, 37.7–59.9 kg/m2) were investigated before and after 12 (GH12) and 24 (GH24) months of GH treatment.Main Outcome Measures:SM cross-sectional area and SM attenuation were determined with computed tomography at the lumbar and midthigh levels. Maximal isometric handgrip strength and isokinetic knee extension peak torque were measured. Motor performance was evaluated with different indoor walking tests, whereas exercise endurance was assessed with a treadmill incremental test to exhaustion.Results:A condition of severe GH deficiency was found in six patients (40%). GH treatment significantly increased lean body mass (GH12, P &lt; .05; GH24, P &lt; .05), reduced percentage of body fat (GH12, P &lt; .05; GH24, P &lt; .05), and augmented SM cross-sectional area and SM attenuation of both lumbar (GH12, P &lt; .01; GH24, P &lt; .001) and thigh muscles (GH24, P &lt; .05). Handgrip strength increased by 7% at GH12 (P &lt; .05) and by 13% at GH24 (P &lt; .001). Peak torque of knee extension extrapolated at zero angular velocity was significantly higher at GH24 (P &lt; .01), and exercise endurance rose by 13% (P &lt; .05) and 17% (P &lt; .05) before exhaustion at GH12 and GH24, respectively, whereas no change was detected with walking tests. No significant difference in the response to GH treatment was detected between patients with and without GH deficiency.Conclusion:Long-term GH treatment in adult PWS patients improves body composition and muscle size and quality and increases muscle strength and exercise tolerance independently from the GH secretory status

The Hg(3,3'-dimethyl-1H,1H'-4,4'-bipyrazolate) coordination polymer: Synthesis, crystal structure and thermal behavior

The novel coordination polymer Hg(Me2BPZ) (H2Me2BPZ=3,3'-dimethyl-1H,1'H-4,4'-bipyrazole) was prepared by reacting the H2Me2BPZ ligand and mercury(II) acetate. The crystal structure of Hg(Me2BPZ), determined by powder X-ray diffraction with laboratory instrumentation, is characterized by a (4,4)-connected 3-D polymeric network, in which the metal ions show a see-saw stereochemistry. Investigating the thermal behavior by thermogravimetric analysis and variable-temperature powder X-ray diffraction revealed that the material is stable up to 340\uc2\ub0C, both under nitrogen and in air, and undergoes a volumetric thermal expansion amounting to \ue2\u88\ubc2% before losing crystallinity

Retraining selective trunk muscle activity: A key to more successful rehabilitation outcomes for hemiparetic stroke patients

Hemiparetic patients lose the ability to move their trunk selectively, abdominals are affected and neither voluntary nor reflex activity is present

The Role of Stress and Cognitive Absorption in Predicting Social Network Addiction

: Nowadays, the use of social networks (SNs) is pervasive and ubiquitous. Among other things, SNs have become a key resource for establishing and maintaining personal relationships, as further demonstrated by the emergence of the pandemic. However, easy access to SNs may be a source of addictive behaviour, especially among the younger population. The literature highlights various psychological and physiological factors as possible predictors of vulnerability to SN addiction. This paper explores the joint effects of stress level and cognitive absorption, in the form of temporal dissociation while on SNs, on the addiction of university students to SNs. Here, 312 participants were involved in an online survey. About 14% of the sample presented a risk for SN addiction. Moreover, it was found that stress level predicted SN addiction both directly and indirectly through the effect of individual temporal dissociation, as experienced during SN usage. These results suggest a significant role of perceived stress level on addiction risk, while also pointing out additional vulnerability to SN addiction for cognitive profiles that are relatively more prone to temporal dissociation while online