MyD88 or TRAM Knockdown Regulates Interleukin (IL)‐6, IL‐8, and CXCL12 mRNA Expression in Human Gingival and Periodontal Ligament Fibroblasts

Background: In a previous report, it was shown that Toll‐like receptor (TLR) 2 knockdown modulates interleukin (IL)‐6 and IL‐8 but not the chemokine CXCL12, an important mediator with inflammatory and proangiogenic effects, in human gingival fibroblasts (HGF) and human periodontal ligament fibroblasts (HPDLF). This study investigates whether knocking down two important TLR adaptor molecules, such as myeloid differentiation protein 88 (MyD88) and TRIF‐related adaptor molecule (TRAM), could affect mRNA expression of IL‐6, IL‐8, and CXCL12 in HGF and HPDLF. Methods: After small interfering (si) RNA‐mediated silencing of MyD88 or TRAM, HGF and HPDLF were stimulated with Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS) or two synthetic ligands of TLR2 (Pam2CSK4 and Pam3CSK4) for 6 hours. IL‐6, IL‐8, and CXCL12 mRNAs were evaluated by quantitative polymerase chain reaction. Results: Knockdown of MyD88 or TRAM partially impaired the IL‐8 mRNA upregulation in both fibroblast subpopulations. Similarly, IL‐6 upregulation was partially prevented by siMyD88 or siTRAM in HGF stimulated with Pg LPS, as well as in both fibroblast subtypes challenged with Pam2CSK4. Conversely, constitutive CXCL12 mRNA levels were upregulated by MyD88 or TRAM knockdown in non‐stimulated cells. Conclusions: These results suggest that TLR adaptor molecules knockdown, such as MyD88 or TRAM, can decrease IL‐6 and IL‐8 mRNA and increase CXCL12 mRNA expression in HGF and HPDLF. This can be an important step for better understanding the mechanisms that control the inflammatory cytokine and chemokine expression, which in turn contributes to periodontal pathogenesis.     

Comparison of Buccal Infiltration of 4% Articaine With 1?:?100,000 and 1?:?200,000 Epinephrine for Extraction of Maxillary Third Molars With Pericoronitis: A Pilot Study

We compared the buccal infiltration of 4% articaine with 1 : 100,000 or 1 : 200,000 epinephrine without a palatal injection for the extraction of impacted maxillary third molars with chronic pericoronitis. This prospective, double-blind, controlled clinical trial involved 30 patients between the ages of 15 and 46 years who desired extraction of a partially impacted upper third molar with pericoronitis. Group 1 (15 patients) received 4% articaine with 1 : 100,000 epinephrine and group 2 (15 patients) received 4% articaine with 1 : 200,000 epinephrine by buccal infiltration. None of the patients in group 1 reported pain, but 3 patients in group 2 reported pain, which indicated a need for a supplementary palatal injection. The palatal injections were all successful in eliminating the pain. Two additional patients in group 2 experienced pain when the suture needle penetrated their palatal mucosa. Based on these results, 4% articaine with 1 : 100,000 epinephrine was found to be more effective for the removal of upper third molars in the presence of pericoronitis than 4% articaine hydrochloride with 1 : 200,000 epinephrine when only a buccal infiltration was used.Key Words: Articaine, Epinephrine, Molar extractionMaxillary third molar extraction is generally straightforward, due to the plasticity of the maxillary bone and to the low resistance to extraction movements. Nevertheless, the anesthetic technique needed for such extraction may be extremely uncomfortable because it requires palatal mucosal anesthesia.^1,2Studies have suggested that articaine has good diffusion through the hard and soft tissues, eliminating the need for the palatal injection in maxillary third molar extractions.^3–6 However, the anesthetic effect may be decreased or neutralized because the inflammation and low tissue pH affects tissue diffusion of the anesthetic, making the drug less effective.^7–9Pericoronitis is the most frequent inflammatory pathology associated with third molars and is caused by a combination of factors including trauma and food impaction with subsequent bacterial colonization and infection.^1,10–13 Clinically, it is characterized by the presence of erythema, swelling, and even ulceration in some cases.^1,14 The management of pericoronitis varies. Many authors have recommended using antibiotic therapy when there are signs of acute infection with systemic involvement such as fever. In cases of chronic or nonacute clinical manifestations, treatment should be limited to antiseptic mouthwashes, irrigation, and anti-inflammatory and/or anesthetic medication. Surgically, the usual treatment is the extraction of the impacted tooth.^1,11–15The aim of the present study was to evaluate the differences between articaine hydrochloride with 1 : 100,000 and 1 : 200,000 epinephrine (adrenaline) administered by buccal infiltration alone (without palatal infiltration) for the removal of impacted upper third molar teeth with pericoronitis.     

Laser Doppler anemometry measurements of steady flow through two bi-leaflet prosthetic heart valves

Introduction

In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench.

Objective

To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream.

Methods

To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. ) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements.

Results

It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found.

Conclusions

Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.     

Low-level laser therapy in different stages of rheumatoid arthritis: a histological study

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease of unknown etiology. Treatment of RA is very complex, and in the past years, some studies have investigated the use of low-level laser therapy (LLLT) in treatment of RA. However, it remains unknown if LLLT can modulate early and late stages of RA. With this perspective in mind, we evaluated histological aspects of LLLT effects in different RA progression stages in the knee. It was performed a collagen-induced RA model, and 20 male Wistar rats were divided into 4 experimental groups: a non-injured and non-treated control group, a RA non-treated group, a group treated with LLLT (780 nm, 22 mW, 0.10 W/cm², spot area of 0.214 cm², 7.7 J/cm², 75 s, 1.65 J per point, continuous mode) from 12th hour after collagen-induced RA, and a group treated with LLLT from 7th day after RA induction with same LLLT parameters. LLLT treatments were performed once per day. All animals were sacrificed at the 14th day from RA induction and articular tissue was collected in order to perform histological analyses related to inflammatory process. We observed that LLLT both at early and late RA progression stages significantly improved mononuclear inflammatory cells, exudate protein, medullary hemorrhage, hyperemia, necrosis, distribution of fibrocartilage, and chondroblasts and osteoblasts compared to RA group (p?<?0.05). We can conclude that LLLT is able to modulate inflammatory response both in early as well as in late progression stages of RA.     

The prevalence of priapism in children and adolescents with sickle cell disease in Brazil

To evaluate priapism rates in individuals <18 years of age with sickle cell disease (SCD) at a referral center. An evaluation was made of 599 consecutive male patients with SCD, separated according to type of hemoglobinopathy (HbSS, HbSC and HbS-β-thalassemia). Age at first episode and number of episodes were recorded. Cases of sickle cell trait were excluded. Mean age was similar in all groups. Overall, priapism occurred in 3.6 % of patients (5.6 % of those with HbSS and 1.1 % of those with HbSC; P = 0.01). In HbSS patients, the prevalence rate of priapism was from 3.5 (CI 95 % 0.94-13.4) when compared with patients with HbSC. No patient with β-thalassemia had priapism. Mean follow-up was 39.7 months (range 1-202 months). Since 91 % of patients with priapism had HbSS, this group was evaluated separately, revealing a rate of priapism of 1.6 % in patients <10 years and 8.3 % in those ≥ 10 years of age (P = 0.002). Regarding priapism in HbSS patients ≥ 10 years (8.3 %) when compared with patients <10 years (1.6 %), the prevalence rate was from 3.3 (CI 95 % 1.1-9.5). Duration of follow-up was not correlated with priapism (P = 0.774). Forty-seven patients were lost to follow-up. Telephone contact was successful with 14/22 patients with priapism, 50 % of whom had required hospital treatment. Most episodes (86 %) occurred at night, always during sleep. Medical interventions were required in 13 cases as follows: intravenous hydration (n = 4), corpora cavernosa puncture and drainage (n = 7) and corpus cavernosum-corpus spongiosum shunts (n = 2). The prevalence of priapism in children <18 years of age with SCD was 3.6 %, lower than previously reported. Prevalence was higher in HbSS patients, increasing in patients >10 years of age. Most episodes occurred at night and half of the patients required some form of urological procedure.