Modulation of the foreign body response to implanted sensor models through device-based delivery of the tyrosine kinase inhibitor,masitinib

The host foreign body response (FBR) adversely effects the performance of numerous implanted biomaterials especially biosensors, including clinically popular glucose-monitoring sensors. Reactive formation of a fibrous capsule around implanted sensors hinders the transport of essential analytes to the sensor from the surrounding tissue, resulting in loss of glucose response sensitivity and eventual sensor failure. Several strategies have sought to mitigate the foreign body response's effects on CGM sensors through the use of local delivery of pharmaceuticals and biomolecules with limited success. This study describes release of a tyrosine kinase inhibitor – masitinib – from the sensor implant to target tissue resident mast cells as key mediators of the FBR. Model implants are coated with a composite polymer hydrophilic matrix that rapidly dissolves upon tissue implantation to deposit slower-degrading polymer microparticles containing masitinib. Matrix dissolution limits coating interference with sensor function while establishing a local controlled-release delivery depot formulation to alter implant tissue pharmacology and addressing the FBR. Drug efficacy was evaluated in a murine subcutaneous pocket implant model. Drug release extends to more than 30 days in vitro. The resulting FBR in vivo, evaluated by implant capsule thickness and inflammatory cell densities at 14, 21, and 28 days, displays statistically significant reduction in capsule thickness around masitinib-releasing implant sites compared to control implant sites.     

Periodontal findings in patients with oral submucous fibrosis and comet assay of affected gingival epithelial cells

Background: Oral submucous fibrosis (OSF) involves large sections of population and is related to certain chewing practices that involve direct exposure of the gingiva to noxious chemicals and additives. The impact of such practices, although studied extensively in relation to the cheek mucosa, is not elucidated as far as gingival tissues are concerned. The possible DNA damage on affected gingiva is also one of the objectives of the present study. Methods: One hundred cases of individuals with OSF and 89 without OSF were examined for periodontal parameters and compared. Biopsies of gingival tissue from both categories were examined with conventional hematoxylin and eosin staining for epithelial, connective tissue, and inflammatory changes. Comet assay of epithelial cells obtained from scraping the gingival surface of both patients with OSF and control individuals was performed . Results: Patients with OSF had poorer oral hygiene and greater loss of attachment, probing depth, and recession compared with controls. Significant histopathologic changes in the form of loss of rete ridges with gingival epithelium reduced to a flattened surface was observed. All the patients with OSF showed comet cells in larger numbers. The controls also showed comet cells but in fewer numbers, and the number of individuals showing comet cells was significantly less. Conclusion: OSF showed significant changes in affected gingiva, and the presence of comet cells in all the patients with OSF is a significant indicator of possible pathognomonic developments.     

The Maintenance of Wakefulness Test in Pediatric Narcolepsy

Objective tools are needed to assess the response to treatment in pediatric narcolepsy. This article presents a single-center experience documenting the use of the maintenance of wakefulness test (MWT) in a pediatric series. This study reviewed the charts of children with narcolepsy who had an MWT performed between January 2008 and June 2012. A cutoff was used for mean sleep latency: <8 minutes for inadequate control of hypersomnia, and >20 minutes to indicate adequate control on medications. Thirteen tests were performed on 10 children (median age 15.8 years, range 8.7-20.3 years) with narcolepsy, of which six had cataplexy and three were boys. Comorbid conditions included Prader-Willi syndrome, bipolar affective disorder, and epilepsy (n = 1 each). The median mean sleep latency for all studies was 16 minutes (range 5.8-40 minutes). Sleep-onset rapid eye movement sleep events were seen in three of 13 studies. In seven patients, findings from the MWT resulted in changes in management. These data suggest that the MWT may be a useful and feasible test for assessing response to treatment in children with narcolepsy. Future research is needed to obtain normative MWT data on children with and without narcolepsy.     

Periodontal findings in a patient with Mauriac syndrome: a case report

Mauriac syndrome is a rare condition that affects people with uncontrolled diabetes. The case history of a 17-year-old female patient diagnosed with Mauriac syndrome and concurrently suffering from type 1 diabetes mellitus (T1DM), stunted growth, hepatomegaly, and severe periodontal disease is described. Non-surgical periodontal therapy was the treatment provided. Severe periodontal destruction was seen in conjunction with the unique features of this syndrome, such as hepatomegaly, dwarfism, moon-shaped face, cushingoid fat deposition, delayed puberty, and brittle diabetes. Treatment resulted in decreased plaque and gingival scores. A bi-directional relationship has been established between diabetes mellitus and periodontal disease and there is an increasing emphasis on perio-systemic interrelationships. Given the effect that such systemic disorders have on periodontal health, periodontists should be involved in the early diagnosis and treatment of such patients.     

Formulation Development,Optimization, and In Vitro–In Vivo Characterization of Natamycin-Loaded PEGylated Nano-Lipid Carriers for Ocular Applications

The present study aimed at formulating and optimizing natamycin (NT)-loaded polyethylene glycosylated nano-lipid carriers (NT-PEG-NLCs) using Box-Behnken design and investigating their potential in ocular applications. Response surface methodology computations and plots for optimization were performed using Design-Expert^® software to obtain optimum values for response variables based on the criteria of desirability. Optimized NT-PEG-NLCs had predicted values for the dependent variables which are not significantly different from the experimental values. NT-PEG-NLCs were characterized for their physicochemical parameters; NT's rate of permeation and flux across rabbit cornea was evaluated, in vitro, and ocular tissue distribution was assessed in rabbits, in vivo. NT-PEG-NLCs were found to have optimum particle size (<300 nm), narrow polydispersity index, and high NT entrapment and NT content. In vitro transcorneal permeability and flux of NT from NT-PEG-NLCs was significantly higher than that of Natacyn^®. NT-PEG-NLC (0.3%) showed improved delivery of NT across the intact cornea and provided concentrations statistically similar to the marketed suspension (5%) in inner ocular tissues, in vivo, indicating that it could be a potential alternative to the conventional suspension during the course of fungal keratitis therapy.     

Effect of aged garlic extract and s-allyl cysteine and their interaction with atenolol during isoproterenol induced myocardial toxicity in rats

Objectives:

The study evaluates the cardioprotective effect of aged garlic extract (AGE) and its constituent; S-allylcysteine (SAC) and their interaction with atenolol during isoproterenol induced cardiac toxicity in rats.

Materials and Methods:

Rats were administered AGE at two different doses of 2 ml/kg or 5 ml/kg orally whereas SAC was administered either at a dose 13.1 mg/kg or 32.76 mg/kg. The AGE or SAC was given alone or in combination with atenolol (6 mg/kg, p.o), every alternate day for three weeks. At the end of treatment, two doses of isoproterenol (150 mg/kg, s.c) were administered to rats. The electrocardiogram (ECG) was recorded followed by withdrawal of blood to estimate serum lactate dehydrogenase (LDH) and creatinine kinase-MB (CK-MB) activities. The activities of LDH, CK-MB as well as superoxide dismutase (SOD), catalase and thiobarbituric acid reactive substances (TBARS) were also determined in the heart tissue homogenate (HTH).

Results:

The isoproterenol induced ECG changes were restored to normal in all treated groups. The AGE and SAC administration caused a decrease in serum LDH and CK-MB activities and an elevation of LDH and CK-MB activities in HTH. Atenolol alone or in combination with AGE and S-allylcsyteine demonstrated similar changes in biomarker activities.

Conclusion:

AGE showed dose-dependent cardioprotection. However, concurrent administration of SAC with atenolol (6 mg/kg, p.o) combated more effectively the myocardial dysfunction during isoproterenol induced cardiotoxicity in rats.KEY WORDS: Acute myocardial injury, aged garlic extract, atenolol, isoproterenol s-allyl cysteine