Preliminary Studies on Solid Lipid Microparticles of Loratadine for the Treatment of Allergic Reactions via the Nasal Route

Purpose: To formulate solid lipid microparticles (SLM) of loratadine (LRT) for the treatment of allergic reactions via the nasal route.Methods: Microparticles were prepared by emulsion congealing technique. The drug content of microparticles was analysed. Drug/excipient compatibility and crystallinity characteristics of microparticles were investigated by Fourier Transform Infrared Spectroscopy (FT-IR) and differential scanning calorimetry (DSC). Particle size distribution was determined by laser diffraction (LD). Drug release from microparticles was compared to that from conventional vehicles (O/W emulsion, gel andoleageneous cream) using Franz-type diffusion cells.Results: Drug content of microparticles was > 87.96 %. FT-IR and DSC analysis indicated that the drug and excipients were compatible for at least 6 months at room temperature after production. Microparticle size was between 86 ± 5.63 ìm and 184 ± 13.21 ìm while mean droplet size of O/Wemulsion was 76 ± 3.45 ìm. Release profiles of LRT from microparticles were significantly different from those of O/W emulsion, gel and  oleageneous cream (p < 0.05). In the case of conventional vehicles,increase in the hydrophilicity of the vehicles led to increase in drug release rate. Drug release fitted generally to zero order kinetics as well as Korsmeyer-Peppas model for one of the SLM formulations, indicating non-Fickian drug release (super case II transport).Conclusion: SLM provided LRT release for a longer period than the conventional vehicles. However, in vivo studies are required to ascertain the effectiveness of the formulations.Keywords: Loratadine, Solid lipid microparticles, Allergy, Controlled drug delivery, Transnasal deliver

Opportunities in utilization of agricultural residues in bio-composite production: Corn stalk (Zea mays indurata Sturt) and oak wood (Quercus Robur L.) fiber in medium density fiberboard

In this paper, corn stalk as an agricultural residue was mixed with oak wood fiber to produce medium density fiberboards (MDF). Urea formaldehyde resin was used as binder. Hygroscopic and mechanical properties were evaluated according to the commercial standards in MDF production. Partial substitution of wood fiber with corn stalks fiber negatively affected all board properties. However, the mechanical properties fulfill the minimum requirements of the relevant standards such as TS-EN 310, 1999 and TS-EN 319, 1999. In some cases, they exceeded the standards, even with partial blending of corn stalk fibers.Key words: Corn stalks, Quercus robur, medium density fiberboard, physical and mechanical properties

Solid Lipid Nanoparticles and Nanostructured Lipid Carriers of Loratadine for Topical Application: Physicochemical Stability and Drug Penetration through Rat Skin

Purpose: To prepare solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) of loratadine (LRT) for the treatment of allergic skin reactions.Methods: SLN and NLC were prepared by high pressure homogenization method. Their entrapment efficiency (EE) and loading capacity (LC) were determined. The physical stability of nanoparticles was investigated during 6 months of storage at room temperature (RT), 4 and 40oC. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and laser diffraction (LD) were used for the investigation of drug:excipient compatibility, thermal behaviour and particle size of the nanoparticles. In vitro release and ex vivo skin penetration of LRT were studied. Nanoemulsions (NE) were also prepared and characterized for comparison.Results: Nanoparticles sizes ranged from 0.222 ± 0.011 μm to 0.252 ± 0.014 μm (D50 as a value based on the volume distribution, the maximum particle diameter below which 50 % of the sample volume exists) They were obtained with high drug payloads (> 90.67 %). LRT was compatible with the other excipients after 6 months. Particle size did not significantly alter particularly at RT. The highest release rate was obtained with NE (1.339 ± 0.026 mcg/ml/h) followed by NLC (1.007 ± 0.011 mcg/ml/h) and SLN (0.821 ± 0.012 mcg/ml/h), indicating anomalous transport (p < 0.05). Penetration profiles of LRT through skin were statistically similar for SLN and NLC (p > 0.05). NE showed the highest penetration rate (0.829 ± 0.06 mcg/cm2/h) (p < 0.05).Conclusion: SLN and NLC of LRT are alternative formulations for immediate treatment of allergic skin reactions with prolonged drug delivery via reservoir action.Keywords: Loratadine, Transdermal delivery, Controlled drug delivery, Solid Lipid nanoparticles, Nanostructured lipid carriers, Allerg

Double-layer Tablets of Lornoxicam: Validation of Quantification Method, In vitro Dissolution and Kinetic Modelling

Purpose: To formulate double-layer tablets of lornoxicam (LRX) prepared by direct compression method and evaluate their physical and drug release  characteristics.Methods: The outer layer of tablets, composed of microcrystalline cellulose (MCC), starch and lactose, incorporated tan initial or prompt dose of the drug (4 mg) for immediate release. Hydroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone (PVP K90) and carbomer, in varying concentrations, were used to prepare the tablet cores for sustained drug delivery. Weight variation, dimensions, hardness,  tensile strength, friability and disintegration time of the tablets were evaluated. Drug release from double-layer tablets as well as kinetic models of drug release were determined after validating the method used for the quantification of the drug. The analytical method for quantification of LRX by UV spectroscopy was validated and verified for linearity, intra-day and inter-day precision, accuracy, recovery and specifity.Results: Tablet cores based on HPMC and HPMC:PVP K90 mixture displayed better compression and flow properties (good and fair to passable) than those  formulated with PVP K90 and carbomer (poor). Satisfactory results were obtained from all the tablet formulations met compendial requirements. The slowest drug release rate was obtained with tablet cores based on PVP K90 (1.21 mg%.h-1). Drug release followed Higuchi kinetic model and the tablet cores released drug by diffusion/polymer relaxation or diffusion/erosion.Conclusion: Double-layer tablet formulation of lornoxicam based on HPMC or HPMC-PVP mixture is suitable for the treatment of inflammatory and painful conditions.Keywords: Lornoxicam, Controlled release, Double-layer tablets, Non-steroidal antiinflammatory drug, Oral deliver

The drum spring (DS) retractor: a constant and continuous force for canine retraction

Although much research has been undertaken on the rate of tooth movement, with different hypotheses having been put forward, the concepts of threshold, light, heavy and optimal forces are not still clear. It has been stressed that an ideal orthodontic spring should have the ability to release a constant force throughout the entire range of its activation, but using traditional techniques applied initial force will decrease, depending on its deactivation due to the tooth movement and the physical properties of the force delivery system. The purpose of this study was to test the clinical use of a new and original spring, the drum spring (DS) retractor (developed in 1992), which applies a constant and continuous force without the need for reactivation, and to compare the effect of a constant and continuous force versus a continuous but diminishing force produced by a traditional pull coil (PC) retractor system on the rate of upper canine retraction. The clinical sample consisted of 15 patients with upper first premolar extractions. For each patient, the upper right canine was retracted by using a DS retractor applying a constant and continuous force of 50 g; the upper left canine was fitted with a conventional PC applying an initial force of 50 g, diminishing proportionally with the distal movement of the canine. In addition, each group was divided according to the age of each patient: eight patients (three males, five females) between 11.8 and 14.4 years of age (mean 13±1.2 years) represented the adolescent group, and seven patients (three males, four females) between 18.8 and 21.6 years of age (mean 18.2±1.9 years) representing the adult group. The experimental period started 1 week after the extraction of the first premolars. During this period no archwire was used, to avoid friction and force level changes, and the both springs were attached to a 6 mm hook fixed on the canine bracket to reduce tipping. The PC retractor was reactivated every 3 weeks whereas the DS retractor was left untouched over the entire experimental period. The study was continued until one of the two canines was completely retracted. The DS retractor was successful for space closure without any reactivation, and the continuous and constant force provided a more rapid canine movement than the continuous but diminishing force. Canine retraction occurred faster in adolescents than in adults. An entire field of clinical and research applications may be influenced by this new type of sprin

The effects of exhaustive swimming and probiotic administration in trained rats: Oxidative balance of selected organs, colon morphology, and contractility

The duration and intensity of exercise are significant factors in oxidative, morphological, and functional changes of the gastrointestinal tract. This study aimed to investigate the effects of both exhaustive swimming and probiotic VSL#3 on rats that had been previously trained with moderate swimming. The rats were divided into four groups labeled: control (C), probiotic (P), exercise (E), and probiotic–exercise (PE). Groups P and PE were fed with probiotic mixture VSL#3. Groups E and PE had a 5-week moderate swimming program (1 h/day for 5 days/week), followed by a 1-week exhaustive swimming program (trained like in moderate program but 3 times with 150 min resting sessions, for 5 days/week). At the end of the program, the rats were euthanized. Malondialdehyde, superoxide dismutase, catalase, and reduced glutathione levels were measured in tissue samples from the gastrocnemius muscle, heart, liver, kidney, and colon. In vitro contractile activity and histomorphology of the colon were also determined. Exercise and/or probiotic decreased the oxidative stress and also increased the level of one or more of the antioxidant enzymes in some of the organs. Probiotics had more pronounced effects on colon morphology than exercise but unexpectedly this effect was non-trophic. In the colon, the thickness of the tunica muscularis and the number of goblet cells were not affected; however, probiotic administration decreased the crypt depth and tunica mucosa thickness. Exercise increased the Emax value of acetylcholine (ACh), while decreased its sensitivity. These findings suggest that exhaustive swimming does not cause oxidative stress and that probiotic consumption improves oxidative balance in trained rats. The probiotic intake does not alter the effect of exercise on the contractile activity of the colon. Colon mucosal changes induced by probiotics are independent of exercise

The effects of swimming exercise and probiotic vsl#3 on zonulin and some inflammatory and oxidative parameters in rats

Moderate exercise stimulates immune system whereas intensive exercise may display immune-suppressive effect associated with the disruption of intestinal barrier. With this study, we tested the effects of moderate and intensive swimming exercises on some cytokines and oxidant variables and zonulin, an intestinal barrier marker, in rats. We also tested possible ameliorative effects of probiotic VSL#3 in both moderate and intensive exercise regimens. Twenty eight rats were randomly divided into 4 equal groups: Control-C, Probiotic-P, Exercise-E, Probiotic+Exercise-PE. The rats in group E and PE underwent moderate swimming exercise for 5 weeks. Following this period, intensive swimming exercise was performed for 5 days. The rats in group C and group P were sedentary. Probiotic VSL#3 was given to group P and PE in the water. At the end of the experiments, serum zonulin, TNF-α, IL-6, IL-10, TGF-β, MDA, and protein carbonyl levels were determined. Evidences obtained from present study indicate that moderate swimming exercise improves barrier integrity of intestine and decreases oxidative stress. During the moderate swimming experiment, probiotic VSL#3 supplementation may also improve inflammatory response. On the other hand, intensive exercise does not led changes in the inflammatory response and oxidative stress, but beneficial responses of moderate exercise on the selected parameters probably disappear due to the intense exercise-induced mild stress

Mixture of learners for cancer stem cell detection using CD13 and H and e stained images

In this article, algorithms for cancer stem cell (CSC) detection in liver cancer tissue images are developed. Conventionally, a pathologist examines of cancer cell morphologies under microscope. Computer aided diagnosis systems (CAD) aims to help pathologists in this tedious and repetitive work. The first algorithm locates CSCs in CD13 stained liver tissue images. The method has also an online learning algorithm to improve the accuracy of detection. The second family of algorithms classify the cancer tissues stained with H and E which is clinically routine and cost effective than immunohistochemistry (IHC) procedure. The algorithms utilize 1D-SIFT and Eigen-Analysis based feature sets as descriptors. Normal and cancerous tissues can be classified with 92.1% accuracy in H and E stained images. Classification accuracy of low and high-grade cancerous tissue images is 70.4%. Therefore, this study paves the way for diagnosing the cancerous tissue and grading the level of it using H and E stained microscopic tissue images. © 2016 SPIE

Utilization of galactomannan from Gleditsia triacanthos in polysaccharide-based films : effects of interactions between film constituents on film properties

The objective of this work was to evaluate the effect of the concentrations of Gleditsia triacanthos galactomannan and glycerol and the presence of corn oil in the physical properties of edible films. The influence of interactions between those constituents on films' permeability to gases (water vapour, CO2 and O2), solubility in water, mechanical properties and colour was evaluated. The effects of those variables were analysed according to a 23 factorial design; regression coefficients were used to understand the influence of each variable (factor) on the studied properties, and a multifactor model was developed. Results show that galactomannan concentration is the most significant factor affecting the studied properties; moreover, the increase of plasticizer concentration and the presence of oil showed to be the most influent in the particular cases of solubility and transport properties (water vapour permeability and O2 permeability), respectively. These results show that galactomannan films' properties can be tailored to allow their use as alternative to non-biodegradable, non-edible packaging materials.The author M. A. Cerqueira is recipient of a fellowship from Fundacao para a Ciencia e Tecnologia (FCT, SFRH/BPD/72753/2010) and B. W. S. Souza is a recipient of a fellowship from the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil (Capes, Brazil)

Towards personalized data-driven bundle design with QoS constraint

Singapore National Research Foundation under its International Research Centre @ Singapore Funding Initiativ