scholarly journals Microparticle and interleukin-1β production with human simulated compressed air diving

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kaighley D. Brett ◽  
Nathan Z. Nugent ◽  
Noelle K. Fraser ◽  
Veena M. Bhopale ◽  
Ming Yang ◽  
...  

Abstract Production of blood-borne microparticles (MPs), 0.1–1 µm diameter vesicles, and interleukin (IL)-1β in response to high pressure is reported in lab animals and associated with pathological changes. It is unknown whether the responses occur in humans, and whether they are due to exposure to high pressure or to the process of decompression. Blood from research subjects exposed in hyperbaric chambers to air pressure equal to 18 meters of sea water (msw) for 60 minutes or 30 msw for 35 minutes were obtained prior to and during compression and 2 hours post-decompression. MPs and intra-particle IL-1β elevations occurred while at pressure in both groups. At 18 msw (n = 15) MPs increased by 1.8-fold, and IL-1β by 7.0-fold (p < 0.05, repeated measures ANOVA on ranks). At 30 msw (n = 16) MPs increased by 2.5-fold, and IL-1β by 4.6-fold (p < 0.05), and elevations persisted after decompression with MPs elevated by 2.0-fold, and IL-1β by 6.0-fold (p < 0.05). Whereas neutrophils incubated in ambient air pressure for up to 3 hours ex vivo did not generate MPs, those exposed to air pressure at 180 kPa for 1 hour generated 1.4 ± 0.1 MPs/cell (n = 8, p < 0.05 versus ambient air), and 1.7 ± 0.1 MPs/cell (p < 0.05 versus ambient air) when exposed to 300 kPa for 35 minutes. At both pressures IL-1β concentration tripled (p < 0.05 versus ambient air) during pressure exposure and increased 6-fold (p < 0.05 versus ambient air) over 2 hours post-decompression. Platelets also generated MPs but at a rate about 1/100 that seen with neutrophils. We conclude that production of MPs containing elevated concentrations of IL-1β occur in humans during exposure to high gas pressures, more so than as a response to decompression. While these events may pose adverse health threats, their contribution to decompression sickness development requires further study.

Author(s):  
Veena M. Bhopale ◽  
Deepa Ruhela ◽  
Kaighley D. Brett ◽  
Nathan Z. Nugent ◽  
Noelle K. Fraser ◽  
...  

Plasma gelsolin (pGSN) levels fall in association with diverse inflammatory conditions. We hypothesized pGSN would decrease due to the stresses imposed by high pressure and subsequent decompression, and repletion would ameliorate injuries in a murine decompression sickness (DCS) model. Research subjects were found to exhibit a modest decrease in pGSN level while at high pressure and a profound decrease after decompression. Changes occurred concurrent with elevations of circulating microparticles (MPs) carrying interleukin (IL)-1β. Mice exhibited a comparable decrease in pGSN after decompression along with elevations of MPs carrying IL-1β. Infusion of recombinant human (rhu)-pGSN into mice before or after pressure exposure abrogated these changes and prevented capillary leak in brain and skeletal muscle. Human and murine MPs generated under high pressure exhibited surface filamentous (F-) actin to which pGSN binds, leading to particle lysis. Additionally, human neutrophils exposed to high air pressure exhibit an increase in surface F-actin that is diminished by rhu-pGSN resulting in inhibition of MPs production. Administration of rhu-pGSN may have benefit as prophylaxis or treatment for DCS.


Author(s):  
Esra Kosan ◽  
Ana Prates-Soares ◽  
Uwe Blunck ◽  
Konrad Neumann ◽  
Kerstin Bitter

Abstract Objectives To investigate the effect of different pre-treatments on the long-term bond strength of fiberglass posts luted either with dual-curing self-etch adhesives and core build-up composites or with a self-adhesive resin (SAR) cement. Materials and methods In total, 180 human root-filled teeth received post-space preparations and three different dentin pre-treatments (PTs): PT1, ethanol (99%); PT2, ethanol-tertiary-butanol-water-solution (AH Plus Cleaner, Dentsply Sirona; York, USA); and PT3, distilled water (control). Five luting systems were used: FU, Futurabond U (Voco; Cuxhaven, Germany); CL, Clearfil DC Bond (Kuraray Noritake; Okayama, Japan); GR, Gradia Core SE Bond (GC Europe NV; Leuven, Belgium); LU, LuxaBond Universal (DMG; Hamburg, Germany); and RX, RelyX Unicem 2 (3M; Minnesota, USA). Roots were cut into six slices (1 mm thick). From each root canal region, three slices were submitted to immediate and three to post-storage push-out testing. The latter were subjected to thermocycling (5–55°C, 6.000 cycles) and stored for six months in saline solution (0.9%, 37°C). Data were analysed using repeated measures ANOVA and chi-square tests (MV±SD). Results Bond strength was significantly affected by material (p<0.0005), pre-treatment (p=0.016), and storage (p<0.0005; repeated-measures ANOVA). LU (18.8±8.1MPa) revealed significantly higher bond strength than RX (16.08±6.4MPa), GR (15.1±4.6MPa), CL (13.95±5.2MPa), and FU (13.7±6.3MPa). PT1 (16.5±6.9MPa) revealed significantly higher bond strength than PT3 (14.5±5.7MPa). Conclusions A universal adhesive in self-etch mode combined with a core build-up material revealed higher bond strength than a SAR cement, both interacted positively with Ethanol pre-treatment. Clinical relevance statement Ethanol (99%) rinsing can be recommended as part of post and core pre-treatment for the investigated luting systems.


2015 ◽  
Vol 119 (3) ◽  
pp. 219-222 ◽  
Author(s):  
Ming Yang ◽  
Veena M. Bhopale ◽  
Stephen R. Thom

An elevation in levels of circulating microparticles (MPs) due to high air pressure exposure and the associated inflammatory changes and vascular injury that occur with it may be due to oxidative stress. We hypothesized that these responses arise due to elevated partial pressures of N2 and not because of high-pressure O2. A comparison was made among high-pressure air, normoxic high-pressure N2, and high-pressure O2 in causing an elevation in circulating annexin V-positive MPs, neutrophil activation, and vascular injury by assessing the leakage of high-molecular-weight dextran in a murine model. After mice were exposed for 2 h to 790 kPa air, there were over 3-fold elevations in total circulating MPs as well as subgroups bearing Ly6G, CD41, Ter119, CD31, and CD142 surface proteins—evidence of neutrophil activation; platelet-neutrophil interaction; and vascular injury to brain, omentum, psoas, and skeletal muscles. Similar changes were found in mice exposed to high-pressure N2 using a gas mixture so that O2 partial pressure was the same as that of ambient air, whereas none of these changes occurred after exposures to 166 kPa O2, the same partial pressure that occurs during high-pressure air exposures. We conclude that N2 plays a central role in intra- and perivascular changes associated with exposure to high air pressure and that these responses appear to be a novel form of oxidative stress.


Methodology ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Manuel C. Voelkle ◽  
Patrick E. McKnight

The use of latent curve models (LCMs) has increased almost exponentially during the last decade. Oftentimes, researchers regard LCM as a “new” method to analyze change with little attention paid to the fact that the technique was originally introduced as an “alternative to standard repeated measures ANOVA and first-order auto-regressive methods” (Meredith & Tisak, 1990, p. 107). In the first part of the paper, this close relationship is reviewed, and it is demonstrated how “traditional” methods, such as the repeated measures ANOVA, and MANOVA, can be formulated as LCMs. Given that latent curve modeling is essentially a large-sample technique, compared to “traditional” finite-sample approaches, the second part of the paper addresses the question to what degree the more flexible LCMs can actually replace some of the older tests by means of a Monte-Carlo simulation. In addition, a structural equation modeling alternative to Mauchly’s (1940) test of sphericity is explored. Although “traditional” methods may be expressed as special cases of more general LCMs, we found the equivalence holds only asymptotically. For practical purposes, however, no approach always outperformed the other alternatives in terms of power and type I error, so the best method to be used depends on the situation. We provide detailed recommendations of when to use which method.


Author(s):  
Colton Haight ◽  
Sandra Moritz ◽  
Tanis Walch

AbstractThe relationships among the time of imagery use on performance and self-efficacy in college baseball players during a hitting task was examined. Participants (n=24) were randomly assigned to one of three imagery conditions: (a) before practice, (b) during practice, (c) after practice. A one-shot MG-M imagery intervention was used. Results from a 3 (imagery group) ×2 (pretest and posttest) repeated measures ANOVA showed only a significant time by imagery group interaction for self-efficacy (F (2, 21)=4.67, p<0.05). These findings suggest that imagery had a stronger psychological effect than physical effect.


2021 ◽  
Vol 11 (4) ◽  
pp. 162
Author(s):  
Boram No ◽  
Naya Choi

Factors of graphomotor skills may serve as indicators to determine a writer’s handwriting proficiency or acclimation to different writing surface textures. This study examines differences in children’s graphomotor skills based on types of writing medium and gender. Participants were 97 six-year-old Korean preschool children who had not received formal writing training prior to the study. Writing tasks were completed on a tablet screen and paper. Writing samples were analyzed using the Eye and Pen software to investigate spatial, temporal, and pressure exertion exhibited during the writing tasks. A repeated measures ANOVA revealed differences in graphomotor skills such as print size, writing speed, and writing pressure. Writing on a tablet screen decreased clarity of writing; print size and speed increased as the stylus slides across the tablet surface with relatively less friction, thereby decreasing the exertion of writing pressure. Analysis of writing differences according to gender indicated that boys generated larger print sizes than girls. Results suggest that while simple writing tasks may be feasible on the tablet screen, providing children with a larger writing medium and encouraging larger print sizes for writing practice, especially for boys, may be beneficial in the development of graphomotor skills among young learners.


2018 ◽  
Vol 7 (2) ◽  
pp. 116
Author(s):  
Budi Darmawan ◽  
Diyah Fatmasari ◽  
Rr. Sri Endang Pujiast

Background: Wet cupping, furthermore mentioned cupping, decreases blood pressures through the level of negative air pressures added by hydrostatics filtration pressure to reinforce the power of fluids filtration in capillaries. However, an appropriate negative air pressure to decrease blood pressure remains an uncertainty.Purpose: This study aimed to analyze negative air pressure differences on cupping in decreasing blood pressures in hypertensive patients.Methods: This is a quasi-experimental design conducted in three Community Health Centers in Langsa City, Aceh, Indonesia. The samples were 36 hypertensive males with age from 45 to 55, who were randomly stratified into two groups with cupping pressures 400 mbar (n=18) as the control group; and 540 mbar (n=18) as the intervention group. The cupping session was performed to each group on T1 (alkahil) point and in the middle line of both shoulders blade points. The systolic blood pressure (SBP) and diastolic blood pressures (DBP) were measured by validated automatic sphygmomanometer. The follow-up periods were one week and two weeks. The data were then analyzed by repeated measures ANOVA.Results: Cupping pressure of 400 mbar decreased the mean of SBP and DPB with a p-value of 0.450 and 0.026, respectively after two weeks of intervention. Meanwhile, cupping pressure of 540 mbar decreased the mean of SBP and DBP with a p-value of 0.006 and 0.057, respectively. Tests of within-subjects resulted in the p-value of 0.250 (SBP) and 0.176 (DBP) after two weeks of intervention. There were no significant differences in SBP and DBP between the intervention group and the control group.Conclusion: The cupping pressure between 400 mbar and 540 mbar could reduce blood pressure; however, the cupping pressure of 540 mbar yielded greater effect in decreasing blood pressure than the 400 mbar. Negative air vacuum pressure loads on cupping to decrease blood pressure should be considered between 400 to 540 mbar, and further studies are needed.


2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
A. Shoemark ◽  
R. Wilson

Bronchiectasis is characterised by neutrophilic bronchial inflammation. Direct measurement of lung inflammation would be useful to assess disease activity, guide need for treatment, and monitor response. The aim of this study was to test whether exhaled breath condensate (EBC) pH, a simple noninvasive test, provides a clinically useful measure of inflammation in the lungs of patients with bronchiectasis. 96 consecutively referred patients were studied when clinically stable, 20 followed up over two years, and a further 22 patients seen during an exacerbation. Subjects breathed tidally for 10 minutes into a condensing chamber (Ecoscreen, Erich Jaeger, Hoechberg, Germany). pH in EBC was measured immediately using a pH probe. In a representative group of 25 patients samples were deaerated with argon gas. This was to control for variations in pH ex vivo by removing CO2. EBC was acidic in bronchiectasis patients () compared to controls () and primary ciliary dyskinesia patients (). pH was related to lung volume but not disease severity. Repeated measures show EBC pH changes with symptoms. EBC is further acidified during an exacerbation of bronchiectasis (), this acidification persists following treatment (). EBC pH is not sufficiently sensitive or specific to monitor patients' health status or provide information to inform acute treatment decisions.


2021 ◽  
Vol 15 (4) ◽  
pp. 256-261
Author(s):  
Gamze Nalci ◽  
Tayfun Alaçam ◽  
Bülent Altukaynak

Background. This study aimed to assess the effects of methyl ethyl ketone (MEK) and ethyl acetate (EA) on dentin microhardness, used as resin sealer solvents. Methods. Eighty halves of single-rooted teeth were randomly divided into four groups to apply MEK, EA, chloroform, or saline solution. Vickers hardness values were measured for three root levels before and after the direct application of solvents for 5 and 15 minutes or a 1-minute application with ultrasonic agitation. The results were analyzed using repeated-measures ANOVA, and adjustments were made for comparisons with Bonferroni tests. Results. The dentin microhardness decreased in all the solvent groups (P<0.05). The changes in microhardness increased with prolonged exposure times, except for the saline solution group. Chloroform exhibited the most significant decrease in value. Furthermore, ultrasonic agitation elicited a more substantial decline in values. Conclusion. MEK and EA might be preferred over chloroform as a solvent for resin sealers because they offer an attenuated decrease in dentin microhardness and do not have gutta-percha-dissolving properties.


2015 ◽  
Vol 5 (1) ◽  
pp. 135-152 ◽  
Author(s):  
Jan Vanhove

I discuss three common practices that obfuscate or invalidate the statistical analysis of randomized controlled interventions in applied linguistics. These are (a) checking whether randomization produced groups that are balanced on a number of possibly relevant covariates, (b) using repeated measures ANOVA to analyze pretest-posttest designs, and (c) using traditional significance tests to analyze interventions in which whole groups were assigned to the conditions (cluster randomization). The first practice is labeled superfluous, and taking full advantage of important covariates regardless of balance is recommended. The second is needlessly complicated, and analysis of covariance is recommended as a more powerful alternative. The third produces dramatic inferential errors, which are largely, though not entirely, avoided when mixed-effects modeling is used. This discussion is geared towards applied linguists who need to design, analyze, or assess intervention studies or other randomized controlled trials. Statistical formalism is kept to a minimum throughout.


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