| 1. |
- Skodje, A., et al.
(författare)
-
Biodegradable polymer scaffolds loaded with low-dose BMP-2 stimulate periodontal ligament cell differentiation
- 2015
-
Ingår i: Journal of Biomedical Materials Research. Part A. - : Wiley. - 1549-3296 .- 1552-4965. ; 103:6, s. 1991-1998
-
Tidskriftsartikel (refereegranskat)abstract
- Poly(l-lactide)-co-(epsilon-caprolactone) [poly(LLA-co-CL)] and poly(l-lactide)-co-(1,5-dioxepan-2-one) [poly(LLA-co-DXO)] are being considered candidate scaffolds for bone tissue engineering. We evaluated the bioactive potential of poly(LLA-co-CL) and poly(LLA-co-DXO) scaffolds loaded with low-dose bone morphogenetic protein-2 (BMP-2). Periodontal ligament (PDL) cells were cultured onto the various scaffolds loaded with 1 μg BMP-2 or without BMP-2 (control). Cell viability, attachment, and proliferation were determined using a methylthiazol tetrazolium (MTT) colorimetric assay at day 1, 3, and 7. Scanning electron microscopy was used to analyze cell morphology at day 7. Cell differentiation was evaluated assaying alkaline phosphatase (ALP) activity at day 7, 14, and 21. Real-time PCR was used to evaluate the mRNA expression of periostin, ALP, type I collagen, bone sialoprotein and BMP-2. A commercially available enzyme-linked immunosorbent assay was used to assess BMP-2 production. Surface analysis disclosed excellent cell attachment, spread, and penetration into the porous scaffolds. The MTT assay indicated that scaffolds loaded with low concentration of BMP-2 did not influence the viability of cells. Cells grown on the modified scaffolds expressed higher levels of osteogenic markers than the nonmodified scaffolds (p<0.05). Poly(LLA-co-CL) and poly(LLA-co-DXO) scaffolds loaded with low-dose BMP-2 exhibited a significant effect stimulating PDL differentiation suggesting a continued evaluation in relevant in vivo models.
|
|
| 2. |
- Fahlstedt, P., et al.
(författare)
-
Dental implant surface morphology, chemical composition, and topography following double wavelength (2780/940 nm) laser irradiation. An in vitro study
- 2023
-
Ingår i: Clinical and Experimental Dental Research. - : Wiley. - 2057-4347. ; 9:1, s. 25-35
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of this in vitro study was to evaluate morphology alterations, chemical composition, and topography of moderately rough dental implants following double-wavelength laser irradiation. Material and Methods: Commercial-grade titanium dental implants representing different surface characteristics (Osseospeed [OS], TiUnite [TiU], and Roxolid SLActive [RS]) were used. Laser irradiation was performed using a computer-controlled robotic device with calibrated energy/power settings and deionized water spray. Micro-, nano-morphology surface alterations, chemical composition, and surface topography (Sa, Sds, Sdr) in the test group (laser plus water), control group A (water only), and control group B (no treatment) were analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and white light laser profilometer (Interferometry). Results: SEM-evaluation revealed minor between-group differences in micro- and nano-morphology within each implant system. Significant overall differences in surface element content were observed between the test and control group B for all implant systems (p <.05). For the test compared with control group B, statistically significantly higher oxygen content was detected for OS and RS (p <.05), a corresponding significant difference was detected for carbon for TiU (p <.05). For RS, a significantly lower content of titanium and zirconium was detected within the test group (p <.05). A significant difference in topography between test and control group B was observed for OS (Sa: p =.039 and Sdr: p =.041) with the highest roughness value for control group B. Conclusions: Altered chemical composition and surface topography were observed for all implant surfaces compared with untreated control following double wavelength laser irradiation. A clinical evaluation of the impact of the altered surface composition following double wavelength laser irradiation on the ability to reosseointegrate appears warranted.
|
|
| 3. |
- Henningsson, Susanne, 1977, et al.
(författare)
-
A randomized placebo-controlled intranasal oxytocin study on first impressions and reactions to social rejection
- 2021
-
Ingår i: Biological Psychology. - : Elsevier BV. - 0301-0511 .- 1873-6246. ; 164
-
Tidskriftsartikel (refereegranskat)abstract
- Oxytocin is central to pair-bonding in non-human animals. We assessed effects of intranasal oxytocin on bond formation between two opposite-sex strangers. In a double-blind placebo-controlled design, 50 pairs of one man and one woman received oxytocin or placebo spray intranasally. After treatment, they played a social interaction game, followed by tasks designed to measure first impressions of the opposite-sex co-participant, and a virtual ball-tossing game (cyberball), designed to measure reactions to rejection by the co-participant. We found no evidence that intranasal oxytocin can improve first impressions of an opposite-sex stranger, and some Bayesian support against this hypothesis. For rejection sensitivity, we observed a sex-and-context-dependent drug effect on post-ostracism mood ratings, consistent with recent studies indicating that interindividual variation and social context can interact with intranasal oxytocin effects. Further research is needed to determine the generalisability of these findings, i.e. if oxytocin can improve first impressions in humans under different conditions.
|
|
| 4. |
- Hovey, Daniel, et al.
(författare)
-
The effect of intranasal oxytocin on visual processing and salience of human faces
- 2020
-
Ingår i: Translational Psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- The mechanisms underlying the role of oxytocin (OT) as a regulator of social behavior in mammals are only partly understood. Recently, it has been proposed that OT increases the salience of social stimuli. We carried out a randomized, double-blind, cross-over study of the effects of OT on binocular rivalry, a visual phenomenon underpinned by the interplay of excitation and inhibition in the cortex. A final sample of 45 participants viewed images of social stimuli (faces with different emotional expressions) and non-social stimuli (houses and Gabor patches). We demonstrate a robust effect that intranasal OT increases the salience of human faces in binocular rivalry, such that dominance durations of faces are longer-this effect is not modulated by the facial expression. We tentatively show that OT treatment increases dominance durations for non-social stimuli. Our results lend support to the social salience hypothesis of OT, and in addition offer provisional support for the role of OT in influencing excitation-inhibition balance in the brain.
|
|
| 5. |
- Loseth, G. E., et al.
(författare)
-
State-dependent mu-opioid modulation of social motivation
- 2014
-
Ingår i: Frontiers in Behavioral Neuroscience. - : Frontiers Media SA. - 1662-5153. ; 8
-
Forskningsöversikt (refereegranskat)abstract
- Social mammals engage in affiliative interactions both when seeking relief from negative affect and when searching for pleasure and joy. These two motivational states are both modulated by mu-opioid transmission. The mu-opioid receptor (MOR) system in the brain mediates pain relief and reward behaviors, and is implicated in social reward processing and affiliative bonding across mammalian species. However, pharmacological manipulation of the mu-opioid system has yielded opposite effects on rodents and primates: in rodents, social motivation is generally increased by MOR agonists and reduced by antagonists, whereas the opposite pattern has been shown in primates. Here, we address this paradox by taking into account differences in motivational state. We first review evidence for mu-opioid mediation of reward processing, emotion regulation, and affiliation in humans, non-human primates, rodents and other species. Based on the consistent cross-species similarities in opioid functioning, we propose a unified, state-dependent model for mu-opioid modulation of affiliation across the mammalian species. Finally, we show that this state-dependent model is supported by evidence from both rodent and primate studies, when species and age differences in social separation response are taken into account.
|
|
| 6. |
- McGoldrick, Daryl J., et al.
(författare)
-
Assessing inter-laboratory comparability and limits of determination for the analysis of cyclic volatile methyl siloxanes in whole Rainbow Trout (Oncorhynchus mykiss)
- 2011
-
Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 85:8, s. 1241-1247
-
Tidskriftsartikel (refereegranskat)abstract
- Cyclic volatile methyl siloxanes (cVMS) are high volume production chemicals used in a wide range of industrial and consumer products. Three cVMS compounds (D4, D5, and D6) have and are undergoing environmental risk evaluations in several countries and have been proposed for legal regulation in Canada. As interest in monitoring concentrations of these chemicals in the environment increase, there is a need to evaluate the analytical procedures for cVMS in biological matrices in order to assess the quality of data produced. The purpose of this study was to determine laboratory testing performance for measuring residues of D4, D5, and D6 in a standard set of fish homogenate samples and to estimate limits of determination for each substance. The samples sent to each laboratory consisted of homogenized whole body tissues of hatchery raised rainbow trout which were fed food fortified with D4, D5, and D6 (dosed) and trout that were fed standard food rations (control). The participants analyzed each sample using their analytical method of choice using their own standards and procedures for quantification and quality control. With a few exceptions, participating laboratories generated comparable results for D4, D5, and D6 in both the dosed and control samples having z-scores between 2 and -2. Method detection limits for the whole fish matrix were on average 2.4 ng g(-1), ww for D4, 2.3 ng g(-1), ww for D5, and 1.8 ng g(-1), ww for D6.
|
|
| 7. |
- Yassin, M. A., et al.
(författare)
-
Surfactant tuning of hydrophilicity of porous degradable copolymer scaffolds promotes cellular proliferation and enhances bone formation
- 2016
-
Ingår i: Journal of Biomedical Materials Research. Part A. - : John Wiley & Sons. - 1549-3296 .- 1552-4965.
-
Tidskriftsartikel (refereegranskat)abstract
- Poly(l-lactide-co-e(open)-caprolactone) (poly(LLA-co-CL)) has been blended with Tween 80 to tune the material properties and optimize cell-material interactions. Accordingly, the aims of this study were fourfold: to evaluate the effect of low concentrations of Tween 80 on the surface microstructure of 3D poly(LLA-co-CL) porous scaffolds: to determine the effect of different concentrations of Tween 80 on proliferation of bone marrow stromal cells (BMSCs) in vitro under dynamic cell culture at 7 and 21 days; to assess the influence of Tween 80 on the degradation rate of poly(LLA-co-CL) at 7 and 21 days; and in a subcutaneous rat model, to evaluate the effect on bone formation of porous scaffolds modified with 3% Tween 80 at 2 and 8 weeks. Blending 3% (w/w) Tween 80 with poly(LLA-co-CL) improves the surface wettability (p<0.001). Poly(LLA-co-CL)/3% Tween 80 shows significantly increased cellular proliferation at days 7 and 21 (p<0.001). Moreover, the presence of Tween 80 facilitates the degradation of poly(LLA-co-CL). Two weeks post-implantation, the poly(LLA-co-CL)/3% Tween 80 scaffolds exhibit significant mRNA expression of Runx2 (p=0.004). After 8 weeks, poly(LLA-co-CL)/3% Tween 80 scaffolds show significantly increased de novo bone formation, demonstrated by μ-CT (p=0.0133) and confirmed histologically. It can be concluded that blending 3% (w/w) Tween 80 with poly (LLA-co-CL) improves the hydrophilicity and osteogenic potential of the scaffolds.
|
|
