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(1/79) Transbuccal delivery of acyclovir (II): feasibility, system design, and in vitro permeation studies.

PURPOSE: To design a buccal mucoadhesive system for systemic delivery of acyclovir using a novel mucoadhesive, copolymers of acrylic acid and poly(ethylene glycol), and to determine the feasibility of transbuccal delivery of acyclovir using this system. METHODS: The buccal delivery system was prepared using an adhesive, a copolymer of acrylic acid and poly(ethylene glycol) monomethylether monomethacrylate, and an impermeable membrane to prevent excessive washout by saliva and to attain unidirectional release. Acyclovir was loaded into the copolymer film prior to lamination of backing material. In vitro drug release studies were conducted in isotonic McIlvaine buffer solution. Buccal permeation of acyclovir was investigated using porcine buccal mucosa with side-by-side flow through diffusion cells at 37;C. Acyclovir was quantified using HPLC. RESULTS: Buccal permeation of acyclovir from the mucoadhesive delivery system was controlled for up to 20 hours with a time lag (t(lag)) of 10.4 hours and a steady state flux of 144.2 microg/cm(2)/h. With the incorporation of NaGC into the system t(lag) was shortened to 5.6 hours with an enhanced steady state flux of 758.7 microg/cm(2)/h. Sustained delivery of acyclovir across bucccal mucosa using this mucoadhesive system was maintained for up to 22 hours. CONCLUSIONS: The mucoadhesive system of P(AA-co-PEG) was shown to be a good candidate for controlled oral mucosal delivery of acyclovir. Buccal delivery of acyclovir was proven feasible based on in vitro permeation studies.  (+info)

(2/79) Polymeric films as vehicle for buccal delivery: swelling, mechanical, and bioadhesive properties.

PURPOSE: To investigate the suitability of an SCMC (sodium carboxymethyl cellulose/polyethylene glycol 400/carbopol 934P) and an HPMC (hydroxypropylmethyl cellulose/polyethylene glycol 400/carbopol 934P) films as drug vehicle for buccal delivery. METHODS: The mechanical and in vitro bioadhesive strength properties of the films were investigated using texture analyzer equipment, while swelling behavior was studied in different media, namely, distilled water and simulated saliva solution. In addition, the in vivo bioadhesion of the film was studied by estimating the film residence time on buccal mucosa of human volunteers. RESULTS: Increase in carbopol 934P content was found to elevate the elasticity, softness and bioadhesive strength but decrease the strength and degree of swelling of both SCMC and HPMC films. SCMC films swelled more extensively in distilled water while HPMC films in simulated saliva solution. HPMC films exhibited greater in vivo bioadhesion although the in vitro bioadhesive strength was lower than SCMC films. Correlation existed between the in vivo and in vitro bioadhesion data within the polymer, but no rank correlation was observed between the two polymers. CONCLUSION: HPMC films may be preferred over SCMC films as drug vehicle for buccal delivery as the former was tougher, more elastic, more bioadhesive in vivo and swelled in a more tolerable manner in the oral cavity than the latter.  (+info)

(3/79) Dendritic cells recruitment and in vivo priming of CD8+ CTL induced by a single topical or transepithelial immunization via the buccal mucosa with measles virus nucleoprotein.

The buccal mucosa, a prototype of pluristratified mucosal epithelia, contains a network of directly accessible class II(+) epithelial dendritic cells (DC), similar to skin Langerhans cells. We showed that a single buccal immunization with measles virus nucleoprotein (NP), by either topical application onto or intradermal injection in the buccal mucosa, induced in vivo priming of protective class I-restricted specific CD8(+) CTL. Both routes of immunization with NP induced a rapid recruitment of DC into the mucosa, which peaked at 2 h and decreased by 24 h. Treatment of mice with Flt3 ligand resulted in an increased number of DC in the buccal mucosa and enhanced the frequency of IFN-gamma-producing NP-specific effectors and the NP-specific CTL response generated after buccal immunization with NP. Finally, NP-pulsed bone marrow-derived DC induced NP-specific IFN-gamma-producing cells upon adoptive transfer to naive mice. These data demonstrate that a viral protein delivered to DC of the buccal mucosa induces in vivo priming of protective anti-viral CD8(+) CTL.  (+info)

(4/79) The use of EMLA for an intraoral soft-tissue biopsy in a needle phobic: a case report.

A case is reported of the removal of a leaf fibroma from the mucosa of the hard palate using EMLA topical anesthesia as the sole means of pain control.  (+info)

(5/79) Evaluation of polyoxyethylene homopolymers for buccal bioadhesive drug delivery device formulations.

Our objective was to evaluate the application of polyoxyethylene homopolymers in buccal bioadhesive drug (BBD) delivery device formulations. The bioadhesive strength of four different molecular weight (MW) polyoxyethylene polymers was measured by Instron tensile tester using glass plate and bovine sublingual tissue as substrate surfaces. Several BBD device formulations containing polyoxyethylene polymer (MW 7,000,000) were prepared by direct compression and compression molding processes. The prepared BBD devices were evaluated for their elasticity, in vitro adhesion and drug release characteristics. The in vivo bioadhesion characteristics of a placebo compression molded device were examined in 3 adult healthy male beagle dogs. The bioadhesive strength of polyoxyethylene polymers appeared to be directly related to their molecular weights. When bovine sublingual mucosa or a glass plate was used as model mucosal substrate surface, the rank order of bioadhesive strength of different molecular weight polyoxyethylene polymers was similar. The bioadhesive strength of devices prepared by the compression molding process was greater than those prepared by direct compression, but the kinetics of drug release were independent of the process used for the preparation of the devices. The drug release and the bioadhesive strength of the similarly prepared device formulations appeared to be dependent on the drug:polymer ratios. The elasticity of the BBD devices prepared by compression molding was improved by the inclusion of polyisobutylene polymer in the formulations. When adhered to the oral cavity of the dogs, the compression molded placebo BBD device exhibited adhesion for at least 4 hours and appeared to show no signs of local irritation. In conclusion, BBD devices containing polyoxyethylene polymer (MW 7,000,000) can be prepared by direct compression or compression molding process in order to provide controlled drug release to the oral cavity while maintaining appropriate bioadhesive characteristics.  (+info)

(6/79) Oral transmucosal fentanyl pretreatment for outpatient general anesthesia.

The oral transmucosal formulation of fentanyl citrate (OTFC) has been reported to be an effective sedative, providing convenient and atraumatic sedation for children prior to general anesthesia or painful diagnostic procedures. Thirty-three young children (24-60 months of age) scheduled for outpatient general anesthesia for treatment of dental caries were enrolled in this randomized placebo-controlled clinical trial. To determine the effectiveness of the OTFC premedication, patient behavior was evaluated using three distinct outcome ratings. A sedation score rated behavior in the waiting room prior to OTFC as well as 10 minutes and 20 minutes after OTFC. A separation score rated the child's response to being separated from his/her parent or guardian for transport to the dental operatory. Finally, a cooperation score rated the child's acceptance of the mask induction. The OTFC formulation was well tolerated by most of the children in this study. Compared with the placebo oralet, the active OTFC improved behavior for separation from the parent (P < .05) and cooperation with the mask induction (P < .05). The duration of surgery and the time of recovery did not differ between placebo and active premedication. Side effects including respiratory and cardiovascular complications were reported more frequently in the active fentanyl group. Continuous monitoring of respiratory function is essential when using this unique and effective formulation of fentanyl for pediatric preanesthetic sedation.  (+info)

(7/79) Phospholipid deformable vesicles for buccal delivery of insulin.

To investigate the possibility of the enhancing effect of deformable vesicles on buccal delivery of insulin, two kinds of vesicles with and without the presence of sodium deoxycholate (deformable vesicles and conventional vesicles) were prepared by reverse phase evaporation methods. The liposomal entrapment efficiency was determined by column chromatography. The particle size and morphology of the vesicles were also evaluated. The hypoglycemic effects, insulin concentrations, and residual amounts of insulin deposited in the buccal membrane after buccal administration of insulin vesicles to rabbits were investigated. Compared with subcutaneous administration of insulin solution, the relative pharmacological bioavailability and the relative bioavailability of buccal administration of insulin vesicles were determined. The results showed that the entrapment efficiencies of the deformable and conventional vesicles were 18.87+/-1.78% (n=3) and 22.07+/-2.16% (n=3), respectively. The particle sizes of the deformable and conventional vesicles were 42.5+/-20.5 nm and 59.7+/-33.8 nm, respectively. There were no significant differences in appearance between the two types of vesicle. Compared with subcutaneous administration of insulin solution, the relative pharmacological bioavailability and the relative bioavailability in the insulin-deformable vesicles group were 15.59% and 19.78%, respectively, which were higher than in the conventional insulin vesicles (p<0.05), blank deformable vesicles and insulin mixture groups (p<0.05). Deformable vesicles have an enhancing effect on buccal delivery of insulin and may be a better carrier than conventional vesicles for buccal delivery of protein drugs.  (+info)

(8/79) Absence of canine oral papillomavirus DNA following prophylactic L1 particle-mediated immunotherapeutic delivery vaccination.

In the canine oral papillomavirus (COPV) model, following wart regression, COPV DNA was detected by PCR at the challenge site. However, following particle-mediated immunotherapeutic delivery (PMID) of COPV L1 and subsequent challenge, no COPV DNA could be detected. These data support PMID of COPV L1 as a protective vaccine and suggest that PMID of L1 may induce virus clearance.  (+info)