Development of a Temperature and pH Dual-Sensitive In-Situ Gel for Treating Allergic Conjunctivitis.

The purpose of this study was to improve the efficacy of olopatadine hydrochloride (OT) in treating allergic conjunctivitis (AC). To achieve this goal, we developed an eye formulation without antimicrobial agents using a temperature-pH dual-sensitive in situ gel technology combined with heat sterilization. Various types of carbomers were evaluated and their optimal doses determined. The prescription containing poloxamer 407 (P407) and poloxamer 188 (P188) was optimized using central composite design for response surface methodology (CCD-RSM). The final optimized dual-sensitive in situ gel (TP-gel) consisted of 0.1% olopatadine hydrochloride, 18.80% P407, 0.40% P188, 0.30% Pemulen™TR-1(TR-1), 4.0% mannitol, and 0.08% Tri(hydroxymethyl)aminomethane(Tris).Sterilization was performed at a temperature of 121℃ for a duration of 20 min. Experimental results showed that TP-gel had good safety profile and remained on the ocular surface for approximately (65.83 ± 8.79) minutes, which is four times longer than eye drops. The expression levels of IL-13, IL-17, and OVA-IgE in mouse ocular tissues with allergic conjunctivitis treated with TP-gel were significantly reduced. This suggests that TP-gel has the potential to be an effective treatment method for allergic conjunctivitis.

Encapsulating an Immunosuppressant Enhances Tolerance Induction by Siglec-Engaging Tolerogenic Liposomes.

Unwanted antibody responses significantly impact human health, and current options for treating deleterious antibody responses largely rely on broad immunosuppressants that can compromise overall immunity. A desirable alternative is to induce antigen-specific immune tolerance. We have shown that co-presentation of antigen and ligands of B cell sialic acid-binding immunoglobulin-like lectins (Siglecs) on a liposomal nanoparticle induces antigen-specific tolerance. Although Siglec-engaging tolerance-inducing antigenic liposomes (STALs) induce robust B cell tolerance in naïve mice, the full potential of STALs requires long-term tolerance induction and suppression of an ongoing immune response. We hypothesized that STALs encapsulated with rapamycin (RAPA), an immunomodulator, could improve the efficacy of STALs and potentially enable their use in the context of immunological memory. Here, we showed that formulation of STALs with RAPA produced enhanced tolerance induction in naïve mice compared to STALs without RAPA but had minimal impact on inducing tolerance in previously sensitized mice. These findings indicate that the addition of immunomodulators to STALs could be beneficial in tolerance induction and support future development of STALs for the treatment of allergy and autoimmune diseases.

Fexofenadine Suppresses Delayed-Type Hypersensitivity in the Murine Model of Palladium Allergy.

Palladium is frequently used in dental materials, and sometimes causes metal allergy. It has been suggested that the immune response by palladium-specific T cells may be responsible for the pathogenesis of delayed-type hypersensitivity in study of palladium allergic model mice. In the clinical setting, glucocorticoids and antihistamine drugs are commonly used for treatment of contact dermatitis. However, the precise mechanism of immune suppression in palladium allergy remains unknown. We investigated inhibition of the immune response in palladium allergic mice by administration of prednisolone as a glucocorticoid and fexofenadine hydrochloride as an antihistamine. Compared with glucocorticoids, fexofenadine hydrochloride significantly suppressed the number of T cells by interfering with the development of antigen-presenting cells from the sensitization phase. Our results suggest that antihistamine has a beneficial effect on the treatment of palladium allergy compared to glucocorticoids.

Effect of nasal sprays on an in vitro survival and morphology of nasoseptal cartilage.

Nasal sprays were introduced several years ago to support the treatment of allergic rhinitis. These sprays may come in direct contact with directly exposed nasoseptal cartilage (e.g. is case of nasoseptal perforation). To date, no studies investigated the effects of nasal sprays on cartilage tissues and cells. Therefore, our aim was to analyze the influence of two different nasal spray types (thixotropic and liposomal) on the vitality of nasoseptal chondrocytes. Human chondrocytes were isolated from surgically dissected tissues. Alternatively, nasal septa (porcine and human) tissue explants were used. The cell or explant cultures were treated with nasal sprays for 4-24 h. As a read-out, cell vitality and gene and protein expression profiles of type I and II collagen, SOX 9 and matrix metalloproteinase MMP-1 were compared to the untreated controls by means of real-time RT-PCR and immunostaining. Using the liposomal, but not thixotropic nasal spray in an explant or chondrocyte in vitro culture led to increased cell death, as compared to the untreated controls. A trend towards suppression of type II collagen and SOX 9 on protein level was found in cultures exposed to liposomal nasal spray, as compared to the controls. The thixotropic nasal spray has not affected the nasoseptal chondrocytes. Further studies with the use of viable nasoseptal cartilage explants and particularly using an in vivo animal model of exposed nasoseptal cartilage are necessary to clear the effect of liposomal spray on chondrocytes.

Anti-Allergic Effects of Quercetin and Quercetin Liposomes in RBL-2H3 Cells.

BACKGROUND: Quercetin is a kind of flavonoid with important bioactivities, such as hypoglycemic, antioxidant, anti-inflammatory, and anti-allergic properties. Although it is unstable, it is worth exploring how to better exert its anti-allergic effect. OBJECTIVE: The current study aimed to elucidate the anti-allergic effect of quercetin liposomes on RBL-2H3 cells in vitro. METHODS: Quercetin liposomes were prepared to improve the anti-allergic activity of quercetin through a green thin-film dispersion method. We compared the anti-allergic effects of quercetin and quercetin liposomes in RBL-2H3 cells. The anti-allergic activity of the quercetin liposomes was evaluated by the level of ß-hexosaminidase, histamine, Ca2+, IL-4, IL-8, and MCP-1. RESULTS: The results showed that quercetin liposomes could significantly restrain the release of ß-hexosaminidase and histamine, calcium influx, and the expression of inflammatory factors, whose effect is stronger than quercetin. CONCLUSION: Collectively, our research suggests that the quercetin liposome can be used as a potential allergy antagonist.

Cellulose sulfate suppresses immunoglobulin E production by murine B lymphocytes in vitro.

BACKGROUND: Immunoglobulin (Ig) E plays an important role in the pathogenesis of allergic diseases such as atopic dermatitis and allergic asthma.We previously reported that a sulfate polysaccharide, fucoidan, suppressed IgE production by murine B cells in vitro. However, the mechanism by which fucoidan suppresses IgE production remains unclear. OBJECTIVE: We incorporated sulfate groups into cellulose and studied their biological characteristics in vitro to explore the possibility of converting biologically neutral polysaccharides to active reagents with antiallergic functions. MATERIAL AND METHODS: Cellulose was chemically processed using N,N-dimethylformamide (DMF) and DMF-sulfurtrioxide and recovered as cellulose sulfate with a molecular weight of around 10 kDa. We then studied the effect of cellulose sulfate on IgE production from B cells, IgE class-switching, and populations of IgE-secreting B cells prepared from murine spleen. We also investigated the effects of sulfated cellulose on the production of interleukin (IL) 4 and interferon (IFN) gamma and the expression of T-bet mRNA by splenic T cells. The cytotoxicity of cellulose sulfate was also examined. RESULTS: Cellulose sulfate suppressed IgE production in B cells stimulated with IL-4 and anti-CD40 antibody by inhibiting IgE class-switch recombination and decreasing the number of IgE-secreting B cells in vitro. Moreover, both cellulose sulfate and fucoidan suppressed IL-4 production and enhanced IFN-gamma production by murine T cells stimulated with anti-CD3 and anti-CD28 antibodies, despite the decrease in T-bet mRNA expression. CONCLUSIONS: Cellulose gains an antiallergic effect on B cells and T cells with the addition of sulfate groups.

Eudragit RL100 based microspheres for ocular administration of azelastine hydrochloride.

In the present study, potential of polymeric microspheres for treatment of allergic conjunctivitis was investigated. Azelastine hydrochloride loaded Eudragit RL100 microspheres were prepared by solvent evaporation technique. The change in drug-polymer ratio on the particle size, zeta potential, entrapment efficiency and in vitro drug release was investigated. As Eudragit concentration ranged from 40 to 80 mg/ml the size range obtained was 4.18-7.36 µm with positive zeta potential. With the increase in drug polymer ratio, the entrapment efficiency was increased with maximum 14.56%. In vitro release studies demonstrated prolonged release of the drug over the period of 6 hr. Scanning electron micrographs showed that microspheres were spherical with distinct solid dense structure. Fourier transform infrared and differential scanning calorimetry studies concluded slight change in peak intensities of drug in microspheres. In vivo studies in rat model indicated that reduction in eosinophil count number was more pronounced in azelastine hydrochloride microspheres than marketed formulation, Azelast®.

In vitro alterations in dental enamel exposed to acidic medicines.

OBJECTIVE: To evaluate the effect of acidic medicines (Klaricid(®), Claritin(®), and Dimetapp(®)) on surface enamel in vitro. METHODS: Enamel blocks (n=104) were randomly distributed into two groups: G1 (pH-cycling simulating physiological oral conditions) and G2 (erosive conditions). Each group was divided into four subgroups, three to be immersed in the medicines and the control in deionized water. Specimen surfaces were evaluated for roughness and hardness at baseline and again after the in vitro experimental phase, which included 30 min immersions in the medicines twice daily for 12 days. Scanning electron microscopy (SEM) was also performed after the in vitro experimental phase. RESULTS: All medicines produced a significant reduction in hardness in G1 after 12 days (P<0.05). The three medicines promoted greater roughness after both pH-regimens - G1 and G2 (P<0.01), except for Claritin in G1. Scanning electron microscopy analysis showed erosive patterns in all subgroups. Dimetapp(®) showed the most erosion and Klaricid(®) the least, in both groups. CONCLUSION: Dimetapp(®) (lowest pH and viscosity) and deionized water (control) showed the most pronounced erosive patterns. Klaricid(®) (highest pH and viscosity) presented an in vitro protective effect against acid attacks perhaps due to its mineral content and viscosity.

D-Pinitol Attenuated Ovalbumin-induced Allergic Rhinitis in Experimental Mice via Balancing Th1/Th2 Response.

Allergic rhinitis (AR) is a complex, chronic immunoinflammatory disorder of the membrane lining of the nasal mucosa. D-Pinitol is considered a cyclic polyol with a potential effect against various allergies. In the present study, we evaluated the anti-allergic effect of pinitol on ovalbumin (OVA)-induced AR model in mice. BALB/c mice were initially sensitized with an intraperitoneal injection of OVA and divided into 5 groups (n=18, in each group) for a treating schedule of distilled water (DW), montelukast (10 mg/kg), and pinitol (5, 10, and 20 mg/kg) through the mouth. Two saline-injected groups were considered as controls by orally administrating DW and pinitol 20. Thereafter, test and control groups were intranasally challenged by OVA and saline, respectively. Our results showed that the OVA challenge caused a marked elevation in AR symptoms like nasal rubbing, sneezing, and discharge which were remarkably diminished using pinitol (10 and 20 mg/kg) and the results were comparable with montelukast. Additionally, increased levels of total and OVA-specific serum Immunoglobulin (Ig) E and IgG1 were significantly attenuated by pinitol as compared to the control group but not the montelukast group. In AR-induced mice, pinitol had significant modulatory effects on representative markers of Th2 (GATA binding protein 3), signal transducer and activator of transcription-6, Interleukins (IL)-4, IL-5, IL-13, suppressors of cytokine signaling 1, Toll-like receptor 4, and myeloid differentiation factor 88), and Type 1 T helper (Th1) immune responses (T-box protein expressed in T cells and Interferon-gamma) as well as the histopathological aberrations induced in the nasal mucosa. In conclusion, Pinitol had potential effects on OVA-induced AR mice through amelioration of nasal symptoms and balancing the Th1/Th2 immune responses during the allergic rhinitis condition.

A Novel Approach of Drug Localization through Development of Polymeric Micellar System Containing Azelastine HCl for Ocular Delivery.

BACKGROUND: Development of polymeric micelles for the management of allergic conjunctivitis to overcome the limitations of topical installation, such as poor patient compliance, poor stromal permeability, and significant adverse effects, increase precorneal residence time and efficacy, and also control the release of drug at the target site. OBJECTIVE: The investigation was aimed at developing a polymeric micellar system of Azelastine HCl for Ocular Delivery. METHODS: Drug loaded micelles of tri-block copolymers Pf 127 were prepared by Thin Film hydration method. The polymeric micelles formulations (F1 to F9) were assessed for entrapment efficiency, micelle size, in vitro permeation, ex vivo transcorneal permeation, in vivo Ocular Irritation, and Histology. RESULTS: Optimized micelles formulation (F3), with the lowest micelle size of 92 nm, least polydispersity value of 0.135, highest entrapment efficiency of 95.30 ± 0.17%, and a cumulative drug permeation of 84.12 ± 1.26% in 8h, was selected to develop pH-sensitive micelles loaded carbopol in situ gel. The optimized in situ gel (G4) proved to be superior in its ex vivo transcorneal permeation when compared with Market Preparation and pure drug suspension, exhibiting 43.35 ± 1.48% Permeation with zero-order kinetics (r2 = 0.9944) across goat cornea. Transmission Electron microscopy revealed spherical polymeric micelles trapped in the gel matrix. A series of experiments showed hydration capability, non-irritancy, and histologically safe gel formulation that had appropriate handling characteristics. CONCLUSION: A controlled release pH-sensitive ocular formulation capable of carrying the drug to the anterior section of the eye via topical delivery was successfully developed for the treatment of allergic conjunctivitis.

Evaluation of neointimal hyperplasia on tranilast-coated synthetic vascular grafts: an experimental study.

Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals.

A novel arctigenin-containing latex glove prevents latex allergy by inhibiting type I/IV allergic reactions.

The present study aimed at developing a natural compound with anti-allergic effect and stability under latex glove manufacturing conditions and investigating whether its anti-allergic effect is maintained after its addition into the latex. The effects of nine natural compounds on growth of the RBL-2H3 cells and mouse primary spleen lymphocytes were determined using MTT assay. The compounds included glycyrrhizin, osthole, tetrandrine, tea polyphenol, catechin, arctigenin, oleanolic acid, baicalin and oxymatrine. An ELISA assay was used for the in vitro anti-type I/IV allergy screening; in this process ß-hexosaminidase, histamine, and IL-4 released from RBL-2H3 cell lines and IFN-γ and IL-2 released from mouse primary spleen lymphocytes were taken as screening indices. The physical stability of eight natural compounds and the dissolubility of arctigenin, selected based on the in vitro pharnacodynamaic screening and the stability evaluation, were detected by HPLC. The in vivo pharmacodynamic confirmation of arctigenin and final latex product was evaluated with a passive cutaneous anaphylaxis (PCA) model and an allergen-specific skin response model. Nine natural compounds showed minor growth inhibition on RBL-2H3 cells and mouse primary spleen lymphocytes. Baicalin and arctigenin had the best anti-type I and IV allergic effects among the natural compounds based on the in vitro pharmacodynamic screening. Arctigenin and catechin had the best physical stability under different manufacturing conditions. Arctigenin was the selected for further evaluation and proven to have anti-type I and IV allergic effects in vivo in a dose-dependent manner. The final product of the arctigenin-containing latex glove had anti-type I and IV allergic effects in vivo which were mainly attributed to arctigenin as proved from the dissolubility results. Arctigenin showed anti-type I and IV allergic effects in vitro and in vivo, with a good stability under latex glove manufacturing conditions, and a persistent anti-allergic effect after being added into the latex to prevent latex allergy.

Heteroarylmethoxyphenylalkoxyiminoalkylcarboxylic acids as leukotriene biosynthesis inhibitors.

A novel series of heteroarylmethoxyphenylalkoxyiminoalkylcarboxylic acids was studied as leukotriene biosynthesis inhibitors. A hypothesis of structure-activity optimization by insertion of an oxime moiety was investigated using REV-5901 as a starting point. A systematic structure-activity optimization showed that the spatial arrangement and stereochemistry of the oxime insertion unit proved to be important for inhibitory activity. The promising lead, S-(E)-11, inhibited LTB(4) biosynthesis in the intact human neutrophil with IC(50) of 8 nM and had superior oral activity in vivo, in a rat pleurisy model (ED(50) = 0.14 mg/kg) and rat anaphylaxis model (ED(50) = 0.13 mg/kg). In a model of lung inflammation, S-(E)-11 blocked LTE(4) biosynthesis (ED(50) of 0.1 mg/kg) and eosinophil influx (ED(50) of 0.2 mg/kg). S-(E)-11 (A-93178) was selected for further preclinical evaluation.

Effect of tranilast on matrix metalloproteinase-1 secretion from human gingival fibroblasts in vitro.

BACKGROUND: Some drugs such as phenytoin, calcium blockers, or cyclosporins are known to cause gingival fibrous hyperplasia, an unwanted side effect. Decreased collagen catabolism in overgrown gingival tissue has been proposed as one of the reasons causing the disease. The effect of tranilast, which suppresses collagen synthesis and cell proliferation, on matrix metalloproteinase (MMP-1) secretion from human gingival fibroblast, was studied in vitro. METHODS: Human gingival fibroblasts were cultured from specimens taken from healthy, periodontal, and overgrown gingival tissues. The effects of tranilast on cell proliferation and MMP-1 secretion from gingival fibroblast were assessed. Inhibitory effect of transforming growth factor (TGF)-beta secretion from gingival fibroblast by tranilast was also evaluated. RESULTS: Tranilast did not interfere with cell proliferation at the low concentrations. MMP-1 concentration significantly increased at the lower doses of tranilast up to about 2-fold compared to controls (P < 0.05). In contrast, higher doses of tranilast significantly decreased activity to 30% and 20%, respectively. MMP-1 secretion was inhibited significantly by phenytoin, nifedipine, and cyclosporin A and the depressed MMP-1 recovered to the control level with tranilast. The amount of secretion from normal and periodontitis gingival fibroblast specimens did not differ, but that from the overgrown gingiva was significantly less than the other types. Moreover, TGF-beta secretion was significantly inhibited by 300 microM of tranilast. CONCLUSIONS: Tranilast upregulates the expression of type 1 collagenase suppressed by gingival overgrowth-inducing drugs, and inhibits TGF-beta secretion from gingival fibroblasts. Therefore, tranilast could be considered as an agent for controlling gingival over-growth.

Interactions of olopatadine and selected antihistamines with model and natural membranes.

OBJECTIVE: Olopatadine, an effective topical ocular human conjunctival mast cell stabilizer/antihistaminic antiallergic drug, was evaluated and compared to selected classical antihistamines for their interaction with model and natural membranes to ascertain potential functional consequences of such interactions. METHODS: The model membranes examined consisted of the argon-buffer interface and monomolecular films of 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine (SOPC) at the argon-buffer interface. Interactions with the model membranes were detected as changes in surface tension, i.e., surface pressure. Functional consequences of these interactions were assessed with natural membranes by 6-carboxyfluorescein leakage, hemoglobin release, lactate dehydrogenase release, and histamine release from appropriate cell types. RESULTS: Measurements at the argon-buffer interface revealed intrinsic surface activity for all agents that ranged from highly surface-active to weakly surface-active in the order of: desloratadine > clemastine > azelastine congruent with ketotifen > diphenhydramine> pyrilamine > emedastine > epinastine > or = olopatadine. This order of amphipathic behavior was confirmed for most of the compounds by estimates of their dissociation constants (K(d,L)) determined from interactions with SOPC monolayers adjusted to a surface pressure approximating that of natural membranes. Epinastine was the only antihistamine that showed a disproportionately greater increase in surface activity toward SOPC in monolayer when compared to other antihistamines. Dissociation constants could not be established for olopatadine because of its low affinity for both the argon-buffer interface and the SOPC monolayer. Functional consequences of these interactions were assessed with natural membranes by 6-carboxyfluorescein leakage (erythrocyte ghosts), hemoglobin release (erythrocytes), lactate dehydrogenase release (conjunctival mast cells, corneal epithelial cells), and histamine release (conjunctival mast cells). Aside from olopatadine and emedastine, all antihistamines promoted a concentration-dependent leakage of hemoglobin from intact erythrocytes. The concentration of drug required to cause half-maximal hemoglobin release (H(50)) from erythrocytes correlated linearly (r = 0.98) with the SOPC dissociation constants (K( d,L)) estimated for the different antihistaminic agents interacting with SOPC monolayers. A similarly high correlation (r = 0.85) emerged from a plot with a slope approaching unity that related drug concentrations required for half-maximal hemoglobin leakage from erythrocytes to threshold doses of drug that caused histamine release from human conjunctival mast cells. Olopatadine was the only agent that did not promote membrane perturbation as monitored by either hemoglobin release from intact erythrocytes, LDH release from human conjunctival mast cells, or 6-carboxyfluorescein release from erythrocyte ghosts. Assessment of the lytic potential of marketed concentrations of ketotifen (0.025%), azelastine (0.05%), and epinastine (0.05%) revealed significant membrane perturbation of human conjunctival mast cells and, importantly, human corneal epithelial cells as indexed by LDH release. This was in contrast to marketed concentrations of olopatadine (0.1%) which maintained normal mast cell and corneal epithelial cell membrane function. CONCLUSIONS: Combined, these results support the notion that the disruption of natural cell membranes by surface-active antihistamines occurs not through a receptor-mediated process, but is the consequence of a direct interaction of these agents with the cell membrane. This is corroborated by surface pressure-concentration isotherms for adsorption of five different antihistaminic agents to SOPC monolayers where 50% lysis occurred at a surface pressure of 42.9 +/- 1.1 mN/m. Olopatadine appears to be unique among the agents tested by demonstrating low intrinsic surface activity, thus limiting its interaction with natural membranes. At concentrations of about half-maximal compound solubility (, 5.0 mM or a 0.19% drug solution), olopatadine generated SOPC monolayer surface pressures (i.e., 39.82 +/- 0.10 mN/m) that were below those that promoted membrane perturbation and onset of hemoglobin leakage. Olopatadine's restricted interaction with membrane phospholipids limits the degree of membrane perturbation and release of intracellular constituents, including histamine, LDH, and hemoglobin, which is believed to contribute to olopatadine's topical ocular comfort and patient acceptance.

[Royal jelly: component efficiency, analysis, and standardisation]. / Ucinkovitost bioloski aktivnih sastavnica maticne mlijeci: analiza I standardizacija.

Royal jelly is a viscous substance secreted by the hypopharyngeal and mandibular glands of worker honeybees (Apis mellifera) that contains a considerable amount of proteins, free amino acids, lipids, vitamins, sugars, and bioactive substances such as 10-hydroxy-trans-2-decenoic acid, antibacterial protein, and 350-kDa protein. These properties make it an attractive ingredient in various types of healthy foods. This article brings a brief review of the molecular mechanisms involved in the development of certain disorders that can be remedied by royal jelly, based on a selection of in vivo and in vitro studies. It also describes current understanding of the mechanisms and beneficial effects by which royal jelly helps to combat aging-related complications. Royal jelly has been reported to exhibit beneficial physiological and pharmacological effects in mammals, including vasodilative and hypotensive activities, antihypercholesterolemic activity, and antitumor activity. As its composition varies significantly (for both fresh and dehydrated samples), the article brings a few recommendations for defining new quality standards.

Effect of sucrose in different commonly used pediatric medicines upon plaque pH in human subjects.

INTRODUCTION: This study was conducted with the aim to investigate the acidogenic potential of three commonly used pediatric medicines (benadryl syrup, crocin syrup, and novamox dry syrup) upon plaque pH. MATERIALS AND METHODS: The protocol used in the study followed the guidelines laid down at Scientific Consensus Conferences on methods for assessment of cariogenic potential of food, San Antonio, Texas. Ten young healthy adult volunteers were selected for the study. Subjects were refrained from brushing their teeth for 48 h and did not eat or drink for at least 2 ½ h prior to each appointment. pH measurements were taken at baseline to determine resting plaque pH and at time interval of 5, 10, 15, 20, 25, and 30 min following a 1 min rinse with each medication. A pooled sample of plaque was removed from buccal / lingual surfaces, thoroughly mixed with 0.6 ml of double distilled deionized water and plaque pH was determined using a glass combination electrode. Data were compared with plaque pH changes after rinsing with control solution of 10 % sucrose and 10 % sorbitol. Analysis of minimum pH, maximum pH drop, and area under the baseline pH was computed for each medicine and for each case and the test of significance was conducted through the unpaired Student 't' test. RESULTS: There was no significant difference between the benadryl syrup, crocin syrup, and sucrose solution as the medicines behaving essentially same as ten percent sucrose solution with respect to their potential to generate acids.

Enhanced transdermal delivery of loratadine from the EVA matrix.

Various enhancers, such as fatty acids (saturated, unsaturated), glycerides, propylene glycols, and non-ionic surfactants, have been incorporated in the loratadine-EVA matrix to increase the rate of skin permeation of loratadine from an EVA matrix. The enhancing effects of these enhancers on the skin permeation of loratadine were evaluated using a modified Keshary-Chien cell fitted with intact excised rat skin. The penetration enhancers showed a higher flux, probably due to the enhancing effect on the skin barrier, the stratum corneum. Among the enhancers used, such as the fatty acids, glycols, propylene glycols, and non-ionic surfactants, linoleic acid showed the best enhancement. For the enhanced transdermal delivery of loratadine, application of an EVA matrix containing a permeation enhancer might be useful in the development of a transdermal drug delivery system.

Microbioassay system for antiallergic drug screening using suspension cells retaining in a poly(dimethylsiloxane) microfluidic device.

This article describes an antiallergic drug-screening system by the detection of histamine released from mast cells (suspension cells) on a multilayer microchip. In this study, the elastmeric material, poly(dimethylsiloxane) (PDMS), was employed to fabricate microchannels and microchambers. The microchip consists of two sections: a histamine-releasing one, which has a cell chamber, and a histamine-derivatizing one. Both were laminated to one microchip. Rat peritoneal mast cells were retained in the cell chamber (1.2 microL) with a filtering system using a cellulose nitrate membrane. This filtering system could easily retain suspension cells without cell damage. Mast cells were viable for a sufficient time to conduct the assay on the cell chamber. The cells were stimulated with a chemical release compound 48/80 (C48/80), and then histamine flowed into the lower layer, where it was derivatized to the fluorescent molecules with o-phthalaldehyde and its fluorescence was detected on the microchip. This flow system could detect the time course of the histamine release, and this microchip system required only 20 min for the assay. By this integrated system, 51 pmol of histamine released from 500 cells was detected, and the number of cells required for the assay was reduced to 1% compared with conventional bulk systems. By comparing the released histamine levels with and without drugs, their effect could be evaluated. The inhibition ratio of C48/80 induced-histamine release using an antiallergic drug, disodium cromoglicate (DSCG), was related to the concentration of DSCG. This flow system was applicable for antiallergy drug screening by rapid measurement of the inhibition of histamine release from a very small amount of mast cells.