Dose‐ and time‐dependent effects of triethylene glycol dimethacrylate on the proteome of human THP‐1 monocytes

Triethylene glycol dimethacrylate (TEGDMA) is commonly used in polymer resin‐based dental materials. This study investigated the molecular mechanisms of TEGDMA toxicity by identifying its time‐ and dose‐dependent effects on the proteome of human THP‐1 monocytes. The effects of different concentrations (0.07–5 mM) and exposure times (0–72 h) of TEGDMA on cell viability, proliferation, and morphology were determined using a real‐time viability assay, automated cell counting, and electron microscopy, and laid the fundament for choice of exposure scenarios in the proteomic experiments. Solvents were not used, as TEGDMA is soluble in cell culture medium (determined by photon correlation spectroscopy). Cells were metabolically labeled [using the stable isotope labeled amino acids in cell culture (SILAC) strategy], and exposed to 0, 0.3 or 2.5 mM TEGDMA for 6 or 16 h before liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) analyses. Regulated proteins were analyzed in the STRING database. Cells exposed to 0.3 mM TEGDMA showed increased viability and time‐dependent upregulation of proteins associated with stress/oxidative stress, autophagy, and cytoprotective functions. Cells exposed to 2.5 mM TEGDMA showed diminished viability and a protein expression profile associated with oxidative stress, DNA damage, mitochondrial dysfunction, and cell cycle inhibition. Altered expression of immune genes was observed in both groups. The study provides novel knowledge about TEGDMA toxicity at the proteomic level. Of note, even low doses of TEGDMA induced a substantial cellular response.     

Facilitators to support the implementation of injury prevention training in youth handball: A concept mapping approach

There is a need for research to identify effective implementation strategies for injury prevention training within real‐world community sports. The aim of this ecological participatory study was to identify facilitators, among stakeholders at multiple levels, that could help injury prevention training become part of regular training routines in youth team handball. Concept mapping, a mixed‐method approach for qualitative data collection and quantitative data analysis, was used. Stakeholders (n = 196) of two community team handball clubs (29% players, 13% coaches, 38% caregivers, 11% club, district and national handball administrators, 9% unknown) participated in a brainstorming process. After the research team synthesized the 235 generated statements, 50 stakeholders (34% players, 22% coaches, 24% caregivers, 20% administrators) sorted 89 unique facilitator statements into clusters and rated them for importance and feasibility. Multidimensional scaling and hierarchical cluster analysis yielded five clusters (stress value 0.231): “Understanding and applying knowledge,” “Education, knowledge, and consistency,” “Set‐up and exercises,” “Inspiration, motivation, and routines,” and “Club policy and expert collaboration.” The cluster “Understanding and applying knowledge” had the highest mean importance (3.17 out of 4) and feasibility (2.93) ratings. The 32 statements rated as both highly important and feasible (Go‐zone) indicate action is required at the individual (end‐users) and organizational (policymakers) levels to implement injury prevention training. Results suggest that developing evidence‐based context‐specific injury prevention training, incorporating physiological, biomechanical and psychological components, and an associated context‐specific implementation plan in partnership with all stakeholders should be a high priority to facilitate the implementation of injury prevention training in youth team handball.     

Impact of Tetrahydropalmatine on the Pharmacokinetics of Probe Drugs for CYP1A2, 2D6 and 3A Isoenzymes in Beagle Dogs

Tetrahydropalmatine (Tet) exhibit multiple pharmacological activities and is used frequently by clinical practitioners. In this study, we evaluate the in vivo effects of single and repeated oral Tet administrations on CYP1A2, 2D6 and 3A activities in six beagle dogs in a randomized, controlled, open‐label, crossover study. A cocktail approach, with dosages of the probe drugs caffeine (3.0 mg/kg), metoprolol (2.33 mg/kg) and midazolam (0.45 mg/kg), was used to measure cytochrome P450 (CYP) metabolic activities. The cocktail was administered orally as a single dose (12 mg/kg) 1 day prior to and 4 days after repeated oral Tet administrations (12 mg/kg three times daily). The probe drugs and their metabolites in plasma were quantified simultaneously by a validated HPLC technique, and non‐compartmental parameters were used to evaluate metabolic variables for assessment of CYP inhibition or induction. Tet had no or minor impact on the pharmacokinetics and metabolism of the probe drugs caffeine and metoprolol, CYP1A2 and CYP2D6 substrates, respectively. However, Tet increased AUC_{0–24 h} and decreased AUC_{ratio(0–24 h)} (1‐hydroxymidazolam/midazolam ratio) for midazolam statistically significant, both in single or multiple dosing of Tet, with up to 39 or 57% increase for AUC_{0–24 h} and 29% or 22 decrease for AUC_{ratio(0–24 h),} respectively, in line with previous in vitro findings for its CYP3A4 inhibition. The extensive use of Tet and herbal medicines containing Tet makes Tet a candidate for further evaluation of CYP3A‐mediated herb–drug interactions. Copyright © 2016 John Wiley & Sons, Ltd.     

In situ localization of interferons in psoriatic lesions

Summary An indirect immunofluorescence technique, using murine monoclonal antibodies (MoAbs) against human IFN- and human IFN- was used to study IFNs in cryostat sections from psoriatic skin lesions. The IFNs were more pronounced in sections from highly active psoriasis than in sections from stationary psoriasis. In highly active psoriatic lesions IFNs- was localized to keratinocytes in stratum basale, to some epidermal dendritic cells, probably Langerhans cells, and to some mononuclear cells in dermis. IFN- was usually not detected in sections from stationary psoriasis. IFN- was localized to stratum corneum, to keratinocytes around microabcesses and to mononuclear cells in the dermal cell infiltrates, predominantly in highly active psoriatic lesions. Both IFN- and IFN- were localized to some endothelial cells in the papillary dermis. The MoAbs did not stain sections from unaffected skin from patients with psoriasis or sections from healthy individuals. The findings indicate that the IFN system in the skin may be of significance in the pathophysiology of psoriasis.     

The effects of long-term oral benfotiamine supplementation on peripheral nerve function and inflammatory markers in patients with type 1 diabetes: a 24-month, double-blind, randomized, placebo-controlled trial

OBJECTIVE

To study the effects of long-term oral benfotiamine supplementation on peripheral nerve function and soluble inflammatory markers in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

The study randomly assigned 67 patients with type 1 diabetes to receive 24-month benfotiamine (300 mg/day) or placebo supplementation. Peripheral nerve function and levels of soluble inflammatory variables were assessed at baseline and at 24 months.

RESULTS

Fifty-nine patients completed the study. Marked increases in whole-blood concentrations of thiamine and thiamine diphosphate were found in the benfotiamine group (both P < 0.001 vs. placebo). However, no significant differences in changes in peripheral nerve function or soluble inflammatory biomarkers were observed between the groups.

CONCLUSIONS

Our findings suggest that high-dose benfotiamine (300 mg/day) supplementation over 24 months has no significant effects upon peripheral nerve function or soluble markers of inflammation in patients with type 1 diabetes.Benfotiamine, a synthetic thiamine monophosphate analog with improved bioavailability compared with thiamine (1), has been shown to prevent the development of microvascular complications in rats without changes in glycemic control (2). Short-term studies (3–12 weeks) in humans have suggested that high-dose benfotiamine (up to 600 mg/day) can improve symptomatic scores in diabetic polyneuropathy (3–5). To assess the efficacy of long-term supplementation, we conducted a 24-month, randomized, double-blind, placebo-controlled study of the effects of 300 mg/day benfotiamine supplementation on peripheral nerve function and inflammatory markers in patients with type 1 diabetes.