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Thermal spray coating is an industrial process in which molten metal is sprayed at high velocity onto a surface as a protective coating. An automated electric arc wire thermal spray coating aerosol generator and inhalation exposure system was developed to simulate an occupational exposure and, using this system, male Sprague-Dawley rats were exposed to stainless steel PMET720 aerosols at 25 mg/msup3/sup × 4 h/day × 9 day. Lung injury, inflammation, and cytokine alteration were determined. Resolution was assessed by evaluating these parameters at 1, 7, 14 and 28 d after exposure. The aerosols generated were also collected and characterized. Macrophages were exposed in vitro over a wide dose range (0-200 µg/ml) to determine cytotoxicity and to screen for known mechanisms of toxicity. Welding fumes were used as comparative particulate controls. In vivo lung damage, inflammation and alteration in cytokines were observed 1 day post exposure and this response resolved by day 7. Alveolar macrophages retained the particulates even after 28 day post-exposure. In line with the pulmonary toxicity findings, in vitro cytotoxicity and membrane damage in macrophages were observed only at the higher doses. Electron paramagnetic resonance showed in an acellular environment the particulate generated free radicals and a dose-dependent increase in intracellular oxidative stress and NF-kB/AP-1 activity was observed. PMET720 particles were internalized via clathrin and caveolar mediated endocytosis as well as actin-dependent pinocytosis/phagocytosis. The results suggest that compared to stainless steel welding fumes, the PMET 720 aerosols were not as overtly toxic, and the animals recovered from the acute pulmonary injury by 7 days.

Research suggests that when dealing with personal setbacks, secondary control (SC) adjustment and acceptance beliefs can foster psychological wellbeing. However, little research has examined these beliefs, in combination, and how they impact students in their academic development. We conducted secondary analysis using an eight-month longitudinal study design over a two-semester introductory course on a sample of university students (

Acquiring strong math skills is essential in science, technology, engineering and mathematics (STEM) education. One important element to foster strong math skills is that students enjoy learning math early on during elementary school years. The control-value theory of achievement emotions (Pekrun, 2006) has been widely used to examine how specific emotions mediate the relationship between cognitive appraisals (i.e., perceived control and value) and math achievement (e.g., Putwain et al., 2018a). However, there has not been a comprehensive study examining the mediating roles of the two commonly experienced emotions—enjoyment and boredom—on international math performance. In this study, Trends in International Mathematics and Science Study (TIMSS) 2015 data is used to evaluate how enjoyment and boredom mediate the influence of cognitive appraisals on math performance in 53 education systems. Specifically, boredom significantly mediates the paths in 25 systems (47%). In general, enjoyment negatively mediates the paths which was an unexpected finding; however, 21 out of the 53 systems (40%) yield expected positive results. Our results therefore advance our understanding regarding how enjoyment and boredom relate to math success. In particular, when the mediating effects are contradictory to our hypothesis (e.g., in Korea and Turkey), these unexpected findings may indicate a cultural difference on what emotions are important to be felt in relation to academic success.

This study used latent transition analysis (LTA) to examine stability and change in the emotion profiles of university students during a two-semester course. Three positive emotions (i.e., hope, pride, and happiness) and five negative emotions (i.e., guilt, helplessness, anger, shame, and regret) derived from Weiner’s attribution theory of emotion (1985, 2007, 2018a, 2018b) were used to identify the emotion profiles of university students at the beginning (Time 1) and end (Time 2) of a two-semester course. We also examined changes in emotion profile memberships over time. Results showed 81% of participants remained in their Time 1 profiles at Time 2, with the majority classified in profiles defined by stable positive emotions or mixed emotions. ANCOVAs indicated that students in the stable positive emotion profile achieved better overall course performance than those with a stable mixed profile or a stable negative emotion profile. An ascending emotion transition profile (Time 1 mixed-to-Time 2 positive) performed better than a stable mixed emotion profile. The present findings extend our current understanding of multifaceted profiles of student emotion that can change over time.

Considerable evidence shows that cell phone use (CPU) is detrimental to students’ academic achievement. However, researchers have yet to consider whether or not perceived academic control (PAC) and anxiety can mediate this effect. In this two-semester study, we examined the role of PAC and learning-related anxiety in affecting the relationship between students’ daily CPU and their final grades in a university course. The study used a series of multiple regressions supplemented by the Hayes’ mediation procedures with a sample of first-year undergraduate students (N = 931) in a research-1 university. The results showed that PAC partially reduced the negative effects of CPU on the grades of the female students while the effects of CPU and PAC were virtually independent for the male students. Anxiety, in turn, did not mediate between CPU and the students’ academic performance for either females or males.

Background The mechanisms driving systemic effects consequent pulmonary nanoparticle exposure remain unclear. Recent work has established the existence of an indirect process by which factors released from the lung into the circulation promote systemic inflammation and cellular dysfunction, particularly on the vasculature. However, the composition of circulating contributing factors and how they are produced remains unknown. Evidence suggests matrix protease involvement; thus, here we used a well-characterized multi-walled carbon nanotube (MWCNT) oropharyngeal aspiration model with known vascular effects to assess the distinct contribution of nanoparticle-induced peptide fragments in driving systemic pathobiology. Results Data-independent mass spectrometry enabled the unbiased quantitative characterization of 841 significant MWCNT-responses within an enriched peptide fraction, with 567 of these factors demonstrating significant correlation across animal-paired bronchoalveolar lavage and serum biofluids. A database search curated for known matrix protease substrates and predicted signaling motifs enabled identification of 73 MWCNT-responsive peptides, which were significantly associated with an abnormal cardiovascular phenotype, extracellular matrix organization, immune-inflammatory processes, cell receptor signaling, and a MWCNT-altered serum exosome population. Production of a diverse peptidomic response was supported by a wide number of upregulated matrix and lysosomal proteases in the lung after MWCNT exposure. The peptide fraction was then found bioactive, producing endothelial cell inflammation and vascular dysfunction ex vivo akin to that induced with whole serum. Results implicate receptor ligand functionality in driving systemic effects, exemplified by an identified 59-mer thrombospondin fragment, replete with CD36 modulatory motifs, that when synthesized produced an anti-angiogenic response in vitro matching that of the peptide fraction. Other identified peptides point to integrin ligand functionality and more broadly to a diversity of receptor-mediated bioactivity induced by the peptidomic response to nanoparticle exposure. Conclusion The present study demonstrates that pulmonary-sequestered nanoparticles, such as multi-walled carbon nanotubes, acutely upregulate a diverse profile of matrix proteases, and induce a complex peptidomic response across lung and blood compartments. The serum peptide fraction, having cell-surface receptor ligand properties, conveys peripheral bioactivity in promoting endothelial cell inflammation, vasodilatory dysfunction and inhibiting angiogenesis. Results here establish peptide fragments as indirect, non-cytokine mediators and putative biomarkers of systemic health outcomes from nanoparticle exposure.

Although theory-driven control striving treatments may sustain motivation for individuals navigating life course transitions, their efficacy during these challenging junctures remains unexamined. In a pre-post randomized field study (n = 316), a novel control striving treatment based on Heckhausen et al.’s (Psychol Rev 117:32–60, 2010) motivational theory of life-span development was administered to young adults making the landmark transition to university. For students who faced obstacles to goal attainment, the motivation-enhancing selective secondary control (SSC) striving treatment (vs. no-treatment) increased performance by 8 % in a two-semester course (74.85 % vs. 66.68 %). Consistent with theory, the SSC treatment-performance linkage was mediated by selective secondary and selective primary control in a hypothesized causal sequence. Findings advance the literature by showing control striving treatments can improve performance for some young adults in transition by promoting adaptive changes in theoretically-derived psychological process variables.

The objective of the current study was to determine if age, diet, and genetic disposition (animal strain) in an animal model had early effects on specific molecular markers in circulating peripheral blood mononuclear cells (PBMCs). Three strains [Sprague-Dawley (SD), Fischer 344 (F344), and Brown-Norway (BN)] of male rats were maintained on a high-fat (HF) or regular diet. Blood was collected at 4, 12, and 24 wk to assess chemistry and to recover PBMCs. Triglycerides and body weight gain increased at all time points in the HF diet group for each strain. Telomere length in PBMCs decreased in the HF diet group compared to the regular diet group up to 24 wk in all strains. Telomere length decreased in PBMCs at 24 wk compared to baseline in all strains, indicating an age-related effect. These findings highlight that diet and age cause changes in PBMCs recovered from different strains of rats. The next tier of studies will examine the contribution of an occupational exposure (e.g., welding fume inhalation) in combination with diet, age, and strain, to assess changes in the molecular responses of isolated PBMCs. In addition, studies involving lifestyle exposure (e.g., tobacco smoke) are in the planning stages and will assess the long-term effects of exposure in our animal model.

A prospective multicenter program was performed to evaluate the combination of rituximab and high-dose (hd) sequential chemotherapy delivered with multiple autologous peripheral blood progenitor cell (PBPC) support (R-HDS-maps regimen) in previously untreated patients with diffuse large B-cell lymphoma (DLB-CL) and age-adjusted International Prognostic Score (aaIPI) score 2-3. R-HDS-maps includes: (i) three APO courses; (ii) sequential administration of hd-cyclophosphamide (CY), hd-Ara-C, both supplemented with rituximab, hd-etoposide/ cisplatin, PBPC harvests, following hd-CY and hd-Ara-C; (iii) hd-mitoxantrone (hd-Mito)/L-Pam + 2 further rituximab doses; (iv) involved-field radiotherapy. PBPC rescue was scheduled following Ara-C, etoposide/cisplatin and Mito/L-Pam. Between 1999 and 2004, 112 consecutive patients aged

Welding generates complex metal fumes that vary in composition. The objectives of this study were to compare the persistence of deposited metals and the inflammatory potential of stainless and mild steel welding fumes, the two most common fumes used in US industry. Sprague-Dawley rats were exposed to 40 mg/m(3) of stainless or mild steel welding fumes for 3 h/day for 3 days. Controls were exposed to filtered air. Generated fume was collected, and particle size and elemental composition were determined. Bronchoalveolar lavage was done on days 0, 8, 21, and 42 after the last exposure to assess lung injury/inflammation and to recover lung phagocytes. Non-lavaged lung samples were analyzed for total and specific metal content as a measure of metal persistence. Both welding fumes were similar in particle morphology and size. Following was the chemical composition of the fumes-stainless steel: 57% Fe, 20% Cr, 14% Mn, and 9% Ni; mild steel: 83% Fe and 15% Mn. There was no effect of the mild steel fume on lung injury/inflammation at any time point compared to air control. Lung injury and inflammation were significantly elevated at 8 and 21 days after exposure to the stainless steel fume compared to control. Stainless steel fume exposure was associated with greater recovery of welding fume-laden macrophages from the lungs at all time points compared with the mild steel fume. A higher concentration of total metal was observed in the lungs of the stainless steel welding fume at all time points compared with the mild steel fume. The specific metals present in the two fumes were cleared from the lungs at different rates. The potentially more toxic metals (e.g., Mn, Cr) present in the stainless steel fume were cleared from the lungs more quickly than Fe, likely increasing their translocation from the respiratory system to other organs.

Background Synthetic vitreous fibers (SVFs) are inorganic noncrystalline materials widely used in residential and industrial settings for insulation, filtration, and reinforcement purposes. SVFs conventionally include three major categories: fibrous glass, rock/slag/stone (mineral) wool, and ceramic fibers. Previous in vitro studies from our laboratory demonstrated length-dependent cytotoxic effects of glass fibers on rat alveolar macrophages which were possibly associated with incomplete phagocytosis of fibers ≥ 17 μm in length. The purpose of this study was to examine the influence of fiber length on primary human alveolar macrophages, which are larger in diameter than rat macrophages, using length-classified Manville Code 100 glass fibers (8, 10, 16, and 20 μm). It was hypothesized that complete engulfment of fibers by human alveolar macrophages could decrease fiber cytotoxicity; i.e. shorter fibers that can be completely engulfed might not be as cytotoxic as longer fibers. Human alveolar macrophages, obtained by segmental bronchoalveolar lavage of healthy, non-smoking volunteers, were treated with three different concentrations (determined by fiber number) of the sized fibers in vitro. Cytotoxicity was assessed by monitoring cytosolic lactate dehydrogenase release and loss of function as indicated by a decrease in zymosan-stimulated chemiluminescence. Results Microscopic analysis indicated that human alveolar macrophages completely engulfed glass fibers of the 20 μm length. All fiber length fractions tested exhibited equal cytotoxicity on a per fiber basis, i.e. increasing lactate dehydrogenase and decreasing chemiluminescence in the same concentration-dependent fashion. Conclusion The data suggest that due to the larger diameter of human alveolar macrophages, compared to rat alveolar macrophages, complete phagocytosis of longer fibers can occur with the human cells. Neither incomplete phagocytosis nor length-dependent toxicity was observed in fiber-exposed human macrophage cultures. In contrast, rat macrophages exhibited both incomplete phagocytosis of long fibers and length-dependent toxicity. The results of the human and rat cell studies suggest that incomplete engulfment may enhance cytotoxicity of fiber glass. However, the possibility should not be ruled out that differences between human versus rat macrophages other than cell diameter could account for differences in fiber effects.

Objectives: The purpose of our retrospective review of prospectively acquired Whole Body Magnetic Resonance (WB-MRI) scans was to assess the incidence of osteonecrosis in patients who received different chemotherapies. Methods: We evaluated the WB-MRI scans performed on 42 patients with Hodgkin Lymphoma treated by three chemotherapy regimens (6ABVD, 2ABVD + 4BEACOPP, 2ABVD + 8BEACOPP), excluding patients with the main risk factors for osteonecrosis. Results: Six out of seven patients (86 %) who received eight BEACOPP and one out of five patients (20 %) treated by four BEACOPP presented osteonecrosis, with a statistically significant difference of frequency between the two groups of patients (p < 0.05); no injury has been reported in patients treated by only ABVD. Among a total of 48 osteonecrotic lesions observed, 48 % were detected in the knee; multifocal osteonecrosis were detected in six out of seven patients (86 %). Conclusions: The development of osteonecrosis is strictly related to the chemotherapy protocol adopted and the number of cycles received, with a strong correlation between the dose of corticosteroids included in the BEACOPP scheme and this complication. WB-MRI can be considered as a helpful tool that allows detecting earlier osteonecrotic lesions in patients treated with corticosteroids. Key Points: • Osteonecrosis is a possible complication of patients with Lymphoma treated by chemotherapy.• Osteonecrosis is related to the corticosteroids included within the BEACOPP protocol.• WB-MRI allows detecting osteonecrotic lesions in patients treated with corticosteroids.