The rheological properties of pharmaceutical foam: implications for use.

We have evaluated various aerosol foam types having different compositions and related physico-chemical properties. The foams assessed were hydroethanolic, emulsion, and aqueous based. Composition, appearance, loss on drying, and rheological properties were analysed to characterise the macrostructure of the different aerosol foams. To confirm the validity of the vane rheological technique used, and facilitate intuitive understanding of the data, similar data were collected for a commercial shaving foam. Of the physico-chemical parameters that were evaluated, rheological properties were distinct among hydroethanolic, emulsion, and aqueous aerosol foam types. The results indicate that beyond composition differences, physico-chemical differences do exist between these aerosol foam types. The viscoelastic flow properties provided an insight of the macrostructure of materials that have been foamed.

Detection of delta-9-tetrahydrocannabinol (THC) in oral fluid, blood and urine following oral consumption of low-content THC hemp oil.

Hemp-derivative (Cannabis sativa L.) food products containing trace levels of Δ-9-tetrahydrocannabinol (THC) are proposed for consumption in Australia and New Zealand; however, it is unclear whether use of these products will negatively affect existing drug screening protocols. This double-blind, within-subjects, cross-over trial assessed 35 adults (17 male; 18 female), aged 22-52 years [Mean=30.7, Standard Deviation (S.D)±7.6]. Low dose THC oil [5mL bearer sesame oil containing 10mg/kg THC (0.046mg THC per 5mL dose)]; high dose THC oil [5mL bearer sesame oil containing 20mg/kg THC (0.092mg THC per 5mL dose)]; and a placebo oil (THC negative) was consumed during a three-week protocol. The Securetec Drugwipe® II Twin device assessed THC presence (cut-off 20ng/mL) in oral fluid at baseline, at 5, 30, 60, 120 and 240min post-treatment. Blood was drawn at baseline, 30, 120 and 240min post-treatment, and urine at baseline and 240min post-treatment. No THC was detected in oral fluid, blood or urine samples at any time-point following consumption of the low or high THC dose. Trace concentrations of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THCa) were detected in blood 4-h after consumption of the high THC treatment (M=0.0001mg/L) and in urine at 4-h post consumption of both low and high THC treatments (M=0.0001mg/L and 0.0004mg/L, respectively). Consumption of low-content THC oil does not result in positive biological assessments. It is therefore highly unlikely that ingestion of products containing these levels of THC will negatively impact existing region-specific drug driving enforcement protocols.

Drug release from hydroethanolic gels. Effect of drug's lipophilicity (logP), polymer-drug interactions and solvent lipophilicity.

We demonstrate drug release properties from hydroethanolic formulations as a function of the drug's lipophilicity (logP), solvent lipophilicity and drug-polymer interactions, for the first time. A hydrophilic polymer, hydroxypropyl cellulose (HPC), provides the non-Fickian slower release of the lipophilic drug, lidocaine (logP=2.6) and the burst (Fickian) release of hydrophilic drug, lidocaine hydrochloride (logP

Simultaneous determination of tretinoin and clindamycin phosphate and their degradation products in topical formulations by reverse phase HPLC.

A new HPLC method based on reverse phase separation and photodiode-array detection has been developed for the simultaneous determination of tretinoin and clindamycin phosphate, and their degradation products in topical formulations. The method has been shown to be stability indicating, accurate, and precise for two different formulation vehicles. Separation was achieved on a reverse phase C18 column (Lichrospher, RP18, 5 microm, 25 cm x 4.6 mm ID, Phenomenex, USA) using a simple gradient with aqueous-acetonitrile and aqueous-methanol mobile phases. The method recovery averaged 100.3% for tretinoin and 99.6% for clindamycin phosphate at a concentration range between 80% and 120% of the label claim. The method can be applied to assess the stability of tretinoin and clindamycin phosphate in pharmaceutical formulations containing tretinoin and clindamycin phosphate individually or in combination as active drugs.

Decrease in measles virus-specific CD4 T cell memory in vaccinated subjects.

Since the licensure and generalization of an effective measles virus (MV) vaccine 41 years ago, antibody levels have been used as correlates of immunity. The long-lived MV-specific antibody response has been studied intensely, but the dynamics of MV-specific T cell immunity over time have not been well characterized. We thus characterized the profiles of MV vaccine-induced antigen-specific T cells over time since vaccination. In a cross-sectional study of healthy subjects with a history of MV vaccination, we found that MV-specific CD4 and CD8 T cells could be detected up to 34 years after vaccination. The levels of MV-specific CD8 T cells and MV-specific IgG remained stable, whereas the level of MV-specific CD4 T cells decreased significantly in subjects who had been vaccinated >21 years earlier. These results show that MV-specific T cell immunity after vaccination is long lasting and reveal different dynamics between CD4 and CD8 cells after vaccination.

Behavioral weight control for overweight adolescents initiated in primary care.

OBJECTIVE: This study evaluates the post-treatment and short-term follow-up efficacy of, as well as participant satisfaction for, a 4-month behavioral weight control program for overweight adolescents initiated in a primary care setting and extended through telephone and mail contact. RESEARCH METHODS AND PROCEDURES: 44 overweight adolescents were randomly assigned to either a multiple component behavioral weight control intervention (Healthy Habits [HH]; n = 23) or a single session of physician weight counseling (typical care [TC]; n = 21). Weight, height, dietary intake, physical activity, sedentary behavior, and problematic weight-related and eating behaviors and beliefs were assessed before treatment, after the 4-month treatment, and at 3-month follow-up. Participant satisfaction and behavioral skills use were measured. RESULTS: HH adolescents evidenced better change in body mass index z scores to post-treatment than TC adolescents. Body mass index z scores changed similarly in the conditions from post-treatment through follow-up. Behavioral skills use was higher among HH than TC adolescents, and higher behavioral skills use was related to better weight outcome. Energy intake, percentage of calories from fat, physical activity, sedentary behavior, and problematic weight-related or eating behaviors/beliefs did not differ by condition or significantly change over time independent of condition. The behavioral intervention evidenced good feasibility and participant satisfaction. DISCUSSION: A telephone- and mail-based behavioral intervention initiated in primary care resulted in better weight control efficacy relative to care typically provided to overweight adolescents. Innovative and efficacious weight control intervention delivery approaches could decrease provider and participant burden and improve dissemination to the increasing population of overweight youth.