Clinical sonopathology for the regional anesthesiologist: part 1: vascular and neural

The use of ultrasound to facilitate regional anesthesia is an evolving area of clinical, education, and research interests. As our community's experience grows, it has become evident that anesthesiologists performing "routine" ultrasound-guided blocks may very well be confronted with atypical or even pathologic anatomy. As an educational resource for anesthesiologists, the following articles present examples of common sonopathology that may be encountered during ultrasound-guided regional anesthesia. This present article describes sonopathology related to blood vessels and nerves.     

A randomized clinical trial comparing 'one-step' and 'two-step' orthodontic bonding systems

OBJECTIVE: The primary objective of this prospective clinical trial was to assess the clinical bond failure rates of orthodontic brackets bonded using a self-etching primer (SEP), compared with brackets bonded using a conventional acid-etched technique with control adhesive (Transbond). A secondary aim was to investigate whether characteristics of the operator, patient or tooth bonded had any influence on bracket failure. DESIGN: Single-centre randomized controlled clinical trial. Thirty-four patients were bonded, each being randomly assigned to either the test or control adhesive. SETTING: NHS Hospital Orthodontic Department, Chester, UK. SUBJECTS: Orthodontic patients requiring fixed appliance treatment. MAIN OUTCOME MEASURES: Bond failure. MAIN OUTCOME RESULTS: Failure rates over the initial 6-month period were 2.0% (Transbond) and 1.7% (SEP) with no statistically significant difference between the two groups. Over the duration of the fixed appliance treatment, bond failure rates increased, but remained acceptable at 7.4 % (TB) and 7.0% (SEP), respectively. When operator, patient and tooth characteristics were analysed, only the bracket location was found to be significant. Maxillary brackets were more likely to fail than mandibular brackets (RR 0.47%; 95% CI 0.22, 1.03). The failure rate for brackets in our study was low when compared with previous studies. CONCLUSIONS: Both the acid-etched control and self-etching primer in combination with adhesive pre-coated brackets were successful for clinical bonding. Their combined failure rate was lower than that reported in similar trials.     

Assembly and organization processes in DNA-directed colloidal crystallization

We present an analysis of the key steps involved in the DNA-directed assembly of nanoparticles into crystallites and polycrystalline aggregates. Additionally, the rate of crystal growth as a function of increased DNA linker length, solution temperature, and self-complementary versus non-self-complementary DNA linker strands (1- versus 2-component systems) has been studied. The data show that the crystals grow via a 3-step process: an initial “random binding” phase resulting in disordered DNA-AuNP aggregates, followed by localized reorganization and subsequent growth of crystalline domain size, where the resulting crystals are well-ordered at all subsequent stages of growth.     

TNF-alpha in asthma

Although only 5-10% of patients with asthma are relatively unresponsive to treatment with inhaled corticosteroids, refractory asthma represents an important condition, as these patients suffer considerable morbidity and mortality and consume a disproportionately large amount of health resource. Treatment options are limited and there is a large unmet clinical need for additional therapies. Tumour necrosis factor (TNF)-alpha is a pro-inflammatory cytokine that has been implicated in many aspects of the airway pathology in asthma, and which has recently been highlighted as potentially important in refractory asthma. The development of neutralising biological agents against TNF-alpha has allowed us to test the role of this cytokine in vivo. Preliminary studies have demonstrated an improvement in lung function, airway hyperresponsiveness and asthma quality-of-life, together with a reduction in exacerbation frequency, in patients treated with anti-TNF-alpha therapy.     

Overview of dietary influences on atherosclerotic vascular disease: epidemiology and prevention

Most dietary recommendations are based on studies of limited power and do not adequately reflect the current knowledge base, particularly with regard to effects of diet on clinical outcomes, the most important endpoint from the patients' perspective. In this review we discusses the current state of dietary research, and present a summary of the evidence upon which to base dietary recommendations and guidelines for atherosclerotic vascular disease prevention. We also highlight the complexity and limitations of interpreting current diet-based epidemiological studies in isolation.