SAT0363 DELPHINIDIN DOSE-DEPENDENTLY DIMINISHES PERIPHERAL IL-17 AND IFN-Γ PRODUCING LYMPHOCYTES IN PSORIATIC ARTHRITIS

Background:

Delphinidin, a dietary anthocyanidin and powerful anti-oxidant from pigmented fruits and vegetables, has broad anti-inflammatory properties. In a human skin model of psoriasis, delphinidin reduced expression of proliferative and inflammatory markers (1).

Objectives:

The rationale of our study was to assess whether delphinidin can in vitro suppress IL-17 and IFN-γ production in peripheral blood mononuclear cell (PBMC) subsets from patients with psoriatic arthritis (PsA).

Methods:

PBMCs were obtained from 24 patients with PsA attending the outpatient clinic of the Department of Rheumatology/clinical Immunology at the University General Hospital of Larissa, Greece. 16 age- and sex-matched healthy volunteers were also included in the study. Delphinidin was supplemented at a concentration ranging from 1 to 50μg/ml, one hour prior to cell stimulation. Cell viability (Annexin V staining) and innate/adaptive lymphocyte subpopulations were assessed by flow cytometry with a panel of fluorochrome-conjugated antibodies against CD56, CD3, CD4 and CD8. Intracellular expression of IL-17 and IFN-γ was measured following PMA/ionomycin stimulation for 5 hours using standard cell permeabilization protocols and monoclonal antibodies against IL-17 and IFN-γ

Results:

Delphinidin at concentration ≥10 μg/ml sharply diminished IL-17-production by CD4(+) T cells (Th17) and CD56(+)CD3(+) (NKT) cells from patients with psoriatic arthritis and normal controls (p≤0.05). IFN-γ producing T (CD4 and CD8) cells, as well as NK and NKT cells were also dose-dependently suppressed following delphinidin pre-incubation in both patients and healthy controls. Inhibition of IFN-γ(+) cells ranged from 27 to 69% and peaked at delphinidin concentration 20-50μg/ml. The inhibitory effect of delphinidin on IL-17 and IFN-γ producing lymphocytes was not due to compromised cell viability, as assessed by annexin V binding.

Conclusion:

Delphinidin exerts, in a dose-dependent manner, a profound in vitro inhibitory effect on T cell and NKT cell IL-17 and IFN-γ production in PsA, and therefore, it may be used as a dietary immunosuppressant, complementary to standard treatment.

References:

[1]Chamcheu JC Skin Pharmacol Physiol. 2015;28(4):177-88. doi: 10.1159/000368445

Disclosure of Interests:

ATHANASIOS MAVROPOULOS: None declared, Sotirios Tsiogkas: None declared, Dimitrios Skyvalidas: None declared, Christos Liaskos: None declared, Aggeliki Roussaki-Schulze Grant/research support from: Received a grant to support the educational and research activities of the department from Genesis Pharma (2018), Speakers bureau: Received honoraria from Genesis Pharma and Janssen(2017) and from Roche and Pharmaserve Lilly(2018), Efterpi Zafiriou Speakers bureau: Received honoraria from Genesis Pharma, Abbvie, Novartis, Roche, Jansses(2017) and Novartis, Abbvie(2018), Dimitrios Bogdanos: None declared, Lazaros Sakkas Grant/research support from: Received a grant to support the educational and research activities of the department from Bristol-Meyers Squib, Speakers bureau: Received honoraria from Actellion(2018), Janssen(2017), Novartis(2017), Sanofi-Aventis(2018), Abbvie(2017) and Roche(2017)

Leaching properties of slag generated by a gasification/vitrification unit: the role of pH, particle size, contact time and cooling method used

The environmental impact from the operation of thermal waste treatment facilities mainly originates from the air emissions, as well as the generated solid residues. The objective of this paper is to examine the slag residue generated by a demonstration plasma gasification/vitrification unit and investigate the composition, the leaching properties of the slag under different conditions, as well as the role of the cooling method used. The influence of pH, particle size and contact time on the leachability of heavy metals are discussed. The main outcome is that the vitrified slag is characterized as inert and stable and can be safely disposed at landfills or used in the construction sector. Finally, the water-cooled slag showed better resistance in relation to heavy metal leachability compared to the air-cooled slag.

Calsenilin is required for endocrine pancreas development in zebrafish

Calsenilin/DREAM/Kchip3 is a neuronal calcium-binding protein. It is a multifunctional protein, mainly expressed in neural tissues and implicated in regulation of presenilin processing, repression of transcription, and modulation of A-type potassium channels. Here, we performed a search for new genes expressed during pancreatic development and have studied the spatiotemporal expression pattern and possible role of calsenilin in pancreatic development in zebrafish. We detected calsenilin transcripts in the pancreas from 21 somites to 39 hours postfertilization stages. Using double in situ hybridization, we found that the calsenilin gene was expressed in pancreatic endocrine cells. Loss-of-function experiments with anti-calsenilin morpholinos demonstrated that injected morphants have a significant decrease in the number of pancreatic endocrine cells. Furthermore, the knockdown of calsenilin leads to perturbation in islet morphogenesis, suggesting that calsenilin is required for early islet cell migration. Taken together, our results show that zebrafish calsenilin is involved in endocrine cell differentiation and morphogenesis within the pancreas.

Light curing time reduction: in vitro evaluation of new intensive light-emitting diode curing units

The aim of the present in vitro study was to establish the minimum necessary curing time to bond stainless steel brackets (Mini Diamond Twin) using new, intensive, light-emitting diode (LED) curing units. Seventy-five bovine primary incisors were divided into five equal groups. A standard light curing adhesive (Transbond XT) was used to bond the stainless steel brackets using different lamps and curing times. Two groups were bonded using an intensive LED curing lamp (Ortholux LED) for 5 and 10 seconds. Two more groups were bonded using another intensive LED curing device (Ultra-Lume LED 5) also for 5 and 10 seconds. Finally, a high-output halogen lamp (Optilux 501) was used for 40 seconds to bond the final group, which served as a positive control. All teeth were fixed in hard acrylic and stored for 24 hours in water at 37 degrees C. Shear bond strength (SBS) was measured using an Instron testing machine. Weibull distribution and analysis of variance were used to test for significant differences. The SBS values obtained were significantly different between groups (P < 0.001). When used for 10 seconds, the intensive LED curing units achieved sufficient SBS, comparable with the control. In contrast, 5 seconds resulted in significantly lower SBS. The adhesive remnant index (ARI) was not significantly affected.A curing time of 10 seconds was found to be sufficient to bond metallic brackets to incisors using intensive LED curing units. These new, comparatively inexpensive, curing lamps seem to be an advantageous alternative to conventional halogen lamps for bonding orthodontic brackets.

Nitric oxide formation in the oropharyngeal tract: possible influence of cigarette smoking

Cigarette smoking reduces the level of nitric oxide (NO) in exhaled air by an unknown mechanism. The view that part of the effect of cigarette smoking on NO production should occur in the oropharyngeal tract is supported by several studies. We have therefore compared smokers and non-smokers regarding non-enzymatic formation of NO from nitrite in the oral cavity since this is a primary candidate target for cigarette smoke. We have also looked at NO synthase-dependent NO formation in the mucosa of the oropharyngeal tract as an alternative target for the inhibitory effect induced by cigarette smoke. Smokers exhaled 67% lower levels of NO than controls (p<0.01, n=15 each group). We could not detect any significant difference in salivary nitrite, nitrate or ascorbate between smokers and non-smokers. Mouthwash with the antibacterial agent chlorhexidine reduced salivary nitrite (-65%) and exhaled NO levels (-10%) similarly in the two groups. Immunohistochemical techniques revealed dense expression of inducible (but not endothelial or neuronal) NO synthase in the squamous epithelium of non-inflamed tonsillar and gingival tissue biopsies. In the same biopsies, significant Ca2+ -independent citrulline-forming activity was detected. We found no difference between smoking and non-smoking subjects regarding NO-synthase expression and in vitro activity. In another group of non-smoking subjects (n=10), spraying the oropharyngeal tract with the NO-synthase inhibitor NG-monomethyl-L-arginine (250 mg) significantly reduced exhaled NO levels for at least 30 min (-18%, p<0.01). Our data suggest that cigarette smoking does not affect non-enzymatic NO formation from nitrite in saliva. However, NO is also formed by inducible NO synthase in the squamous epithelium of the normal oropharyngeal tract. We suggest that cigarette smoking may down-regulate enzymatic NO formation in the oropharyngeal compartment as well as in the bronchial compartment.

Effect of different masticatory functional and mechanical demands on the structural adaptation of the mandibular alveolar bone in young growing rats

The influence of masticatory functional and mechanical demands on the structural adaptation of the alveolar bone has not been investigated in both animals and humans. The effect of two experimental factors, the insertion of a bite-opening appliance and the alteration of food consistency, was investigated in young growing rats, with a particular emphasis on three-dimensional (3D) bone microstructure. Thirty-six male albino rats were divided into two equal groups, fed with either the standard hard diet or soft diet, at the age of 4 weeks. After 2 weeks, half of the animals in both groups had their upper molars fitted with an upper posterior bite block, an appliance similar to those used in clinical orthodontics. The remaining animals served as a control. After another 4 weeks, the animals were sacrificed, and their left hemimandibles were excised. Bone mineral density (BMD) and bone microstructure parameters of the alveolar process were subsequently measured, using dual-energy X-ray absorptiometry (DXA) and micro-computed tomography (micro-CT). The alveolar process width was also measured. Both experimental factors led to significant shape and structure modification of the mandibular alveolar bone in the growing rat. The bite block applied a continuous light force, which was associated with an inhibition of alveolar process vertical growth and a significant increase of cortical thickness. Soft diet and the consequent reduction of the intermittent forces applied to the alveolar bone during mastication resulted in a reduction of bone mineral density, accompanied by decreased trabecular bone volume and thickness. This rat model could prove to be a useful tool for the in vivo investigation of the role of muscular forces on the shape and structure adaptation of bone.

In vivo evaluation of two new moisture-resistant orthodontic adhesive systems: a comparative clinical trial

OBJECTIVE

To evaluate and compare the clinical performance of two new moisture-resistant orthodontic adhesive systems: a chemically-cured composite resin (Unite, 3M Unitek, Monrovia, California, USA) in conjunction with a special moisture-resistant primer (Transbond MIP, 3M Unitek, Monrovia, California, USA); and a fluoride-releasing light-cured compomer (Assure, Reliance Orthodontic Products, Inc., Itasca, Illinois, USA).

DESIGN

Randomized controlled clinical trial using the 'split-mouth' technique.

SETTING

Department of Orthodontics, Aristotle University of Thessaloniki.

SUBJECTS (MATERIALS) AND METHODS

Twenty-five consecutively started patients (13 females and 12 males) requiring fixed appliance orthodontic treatment.

INTERVENTIONS

Four-hundred-and-thirty-six stainless steel brackets bonded to all teeth except molars using two different moisture-resistant orthodontic adhesive systems.

MAIN OUTCOME MEASURES

Bond failure rates during a period of 9 months were estimated for each adhesive system and the corresponding bracket survival curves were plotted using the Kaplan- Meier product-limit estimate. Bracket survival distributions with respect to adhesive material, tooth location, patient's gender and operator, were then compared by means of a log-rank test. Bond failure interface was determined using the Adhesive Remnant Index.

RESULTS

Assure recorded a higher bond failure rate (13.8 per cent) than Unite & MIP (7.3 per cent). The corresponding bracket survival curves were found to be significantly different (P < 0.05). Premolars exhibited higher bond failures than incisors and canines (P < 0.001), while half (49.8 per cent) of the total bond failures occurred during the first 2 months of treatment. The predominant mode of failure was within the bonding material.

CONCLUSION

The new moisture-resistant adhesive systems under study were found to be clinically efficient, though Assure exhibited a significantly higher bond failure rate than Unite and Transbond MIP. The higher frequency of adhesive failures observed with Assure might indicate a possible weak point at the adhesive-bracket interface.

In vivo evaluation of a moisture-activated orthodontic adhesive: a comparative clinical trial

OBJECTIVES

To evaluate and compare the clinical performance of a water-activated, ethyl-cyanoacrylate adhesive to a conventional composite resin. The null hypothesis tested was that there was no difference in bracket survival distribution, over a period of orthodontic treatment, for brackets bonded with either bonding agent.

DESIGN

Single center randomized controlled clinical study.

SETTING AND SAMPLE POPULATION

Twenty-five consecutive patients (15 females and 10 males) were selected and treated with fixed appliances in a university postgraduate orthodontic clinic. All teeth, but the molars, were bonded with twin stainless steel brackets (n = 429) using a split-mouth technique and random allocation of the two adhesives.

OUTCOME MEASURE

Bond failure rates during a period of 9 months were estimated for each adhesive system and the corresponding bracket survival curves were plotted using the Kaplan-Meier product-limit estimate. Bracket survival distributions with respect to adhesive material, tooth location, investigator, and bond failure interface were then compared by means of a log-rank test. Bond failure interface was determined using the Adhesive Remnant Index (ARI).

RESULTS

The water-activated bonding material recorded a significantly higher bond failure (22.4%) than the composite resin (5.1%). There were also statistically significant differences in bracket survival distributions between the two adhesives (log-rank test: p < 0.001). Premolars exhibited higher bond failure rates than incisors and canines (p < 0001). The predominant mode of failure was within the bonding material.

CONCLUSION

Further investigations focused on the improvement of the physical and mechanical properties of the water-activated bonding system are needed to make it a reliable alternative adhesive for the direct bonding of orthodontic brackets.

The acute effects of smokeless tobacco (snuff) on gingival blood flow in man

Snuff-induced blood flow responses in the gingiva were evaluated in 22 healthy casual consumers of tobacco. Laser Doppler flowmetry (LDF) was used to measure blood flow simultaneously and continuously on two gingival sites (buccal aspect of the papillae between the upper lateral incisors and canines). In addition, measurements of skin blood flow in the forehead and palmar side of the left thumb were performed. Arterial blood pressure (BP) and heart rate (HR) were also recorded. Unilateral application of commercial snuff (500 mg, 1%) caused a marked and rapid increase in gingival blood flow (GBF) on the exposed side (p < 0.001). Blood flow increased also in the contralateral gingiva and forehead skin (p < 0.05). Skin blood flow in the thumb showed an insignificant decrease. BP and HR increased. Vascular conductance increased significantly in the snuff-exposed gingiva but not in the contralateral gingiva or the forehead. Vascular conductance was largely unaffected in the thumb. It is concluded that acute application of snuff, besides giving rise to typical changes in BP and HR, increases GBF in and around the exposed area, probably through activation of sensory nerves and the subsequent release of vasodilatory peptides from their peripheral endings. Blood flow in unexposed gingival and forehead skin may increase probably due to humoral or nervously mediated mechanisms. However, a passive pressure-induced hyperaemia in the unexposed gingiva and forehead skin can not be excluded.

Effects of mandibular nerve block on heat- or cold-induced changes in pulpal blood flow in man

Laser Doppler flowmetry (LDF) was used to study the effect of mandibular nerve block, using 3% mepivacain, on heat- or cold-induced changes in pulpal blood flow (PBF) evoked by application of cold or heat to the lingual surfaces of teeth 33 and 43 in nine young subjects. PBF on average showed a 7% increase in response to heat (48 degrees C) and a 20% decrease when exposed to cold (3 degrees C). Neither response was affected by mandibular block. From this we concluded that the effects on PBF of the presently applied heating and cooling of the tooth were solely due to direct thermal influences on the blood vessels, without involvement of vasomotor or sensory nerves.