Accelerated schedule of hepatitis B vaccination in high-risk youth

Objective : To perform a feasibility and immunogenicity study of an accelerated schedule of hepatitis B immunization for high-risk youth.
Methodology : High-risk adolescents attending a youth health centre and nearby youth refuges were immunized with Engerix-B recombinant vaccine, 20 μg intramuscularly, at 0,2 and 6 weeks. Serology was performed prior to immunization and 3 months after the third dose.
Results : Forty-two subjects (27 female) aged 13-20 years entered the study. Two (4.8%), already hepatitis B virus (HBV) seropositive, were excluded. Thirty-six of 40 subjects had one or more risk factors for HBV. Participants were often elusive, needing multiple attempts to establish contact. Twenty (50%) of the 40 completed three immunizations and all 14 studied developed anti-hepatitis B surface titres of > 100mlU/mL (geometric mean titre 630 mIU/mL, 95% confidence intervals 309-1290).
Conclusion : High-risk youth can be immunized against hepatitis B successfully using an accelerated schedule, but compliance is difficult.     

A comparison of changes in dental students'' and medical students'' approaches to learning during professional training

The purposes of this study were 1) to compare the learning approaches of dental students (DS) and medical students (MS) for the Class of 1998 at a single institution at admission and graduation and 2) to determine if their learning approaches changed over the course of their studies. An Approaches to Studying Inventory (ASI) was administered to DS and MS at two times: their first month in school and their last month in school. Means and standard deviations were calculated for three ASI orientations to studying: 'Meaning', 'Reproducing', and 'Achieving'. An additional domain referred to as 'Styles and Pathologies' identified learning problems. In comparison, DS and MS demonstrated a different pattern of learning approaches at matriculation; however, at graduation these differences were less apparent. Over time, DS reported a decreased use, and MS reported an increased use of the Reproducing orientation bringing them closer together. MS also demonstrated an increased use of the Achieving orientation. The Meaning orientation, which indicates a deep approach to learning, was equivalently used by both groups at entry and remained unaltered.     

Enamel defects and salivary methylmalonate in methylmalonic acidemia

Introduction and objective:  To characterize enamel defects in patients with methylmalonic acidemia (MMA) and cobalamin (cbl) metabolic disorders and to examine salivary methylmalonate levels in MMA.
Subjects and methods:  Teeth from patients ( n  = 32) were evaluated for enamel defects and compared with age- and gender-matched controls ( n  = 55). Complementation class ( mut , cblA , cblB and cblC ) and serum methylmalonate levels were examined. Primary teeth from two patients were examined by light and scanning electron microscopy and salivary methylmalonate levels from two patients were analyzed.
Results:  Enamel defects were significantly more prevalent per tooth in the affected group than the control group, across complementation types ( P  <   0.0001). The mut MMA subgroup had a significantly higher prevalence per individual of severe enamel defects than controls ( P  =   0.021), and those with enamel defects exhibited higher serum methylmalonate levels than those without ( P  = 0.017). Salivary methylmalonate levels were extremely elevated and were significantly higher than controls ( P  =   0.002). Primary teeth were free of enamel defects except for two cblC patients who exhibited severe enamel hypoplasia. One primary tooth from a cblC patient manifested markedly altered crystal microstructure.
Conclusion:  Enamel anomalies represent a phenotypic manifestation of MMA and cbl metabolic disorders. These findings suggest an association between enamel developmental pathology and disordered metabolism.     

Nanoparticles: small and mighty

The properties of engineered nanomaterials and nanoparticles such as zinc oxide and titanium dioxide may differ substantially from naturally occurring materials and particles. Nanoparticles have unique physical properties making them ideal for use in various skin care products currently on the market. Nano-preparations are currently under investigation as novel treatments of acne vulgaris, recurrent condyloma accuminata, atopic dermatitis, hyperpigmented skin lesions, and other non-dermatologic diseases. Because of their increased surface area, nanoparticles have increased reactivity and a small size allowing for enhanced mobility through the human body and environment. As their use becomes more prevalent, nanoparticles are being scrutinized for their safety and long-term effects. This review discusses the benefits of nanoparticles in dermatological therapies and skin care products as well as potential disadvantages and possible mechanisms of toxicity.