Effect of duration of force application on blood vessels in young and adult rats.

Introduction: Age effects on orthodontically induced periodontal vascular reactions have not been studied. The aim of the present study was to test the hypothesis that prolonged tooth movement induces age-related increases in periodontal vascularity.

Methods: A standardized orthodontic appliance was placed in 2 groups of 30 rats aged 6 weeks and 9 to 12 months.

Age-dependent external root resorption during tooth movement in rats.

Objective: To investigate the effect of age on root resorption and distribution along different parts of the root during prolonged light force application.

Material And Methods: Orthodontic appliances were placed in two groups of 30 rats (one group 6 weeks old, the other 9-12 months old), with contralateral sides as controls. Groups of animals were killed at 1, 2, 4, 8, and 12 weeks.

Pore direction in relation to anisotropy of mechanical strength in a cubic starch compact.

The purpose of this research was to evaluate the relation between preferential direction of pores and mechanical strength of cubic starch compacts. The preferential pore direction was quantified in SEM images of cross sections of starch compacts using a previously described algorithm for determination of the quotient of transitions (Q). This parameter and the mechanical strength were evaluated in compacts of different porosities.

Endoscope disinfection and its pitfalls--requirement for retrograde surveillance cultures.

Background And Study Aims: Several endoscopy-related outbreaks of infection have been reported in recent years. For early recognition of inadequate disinfection of endoscopes we designed a microbiological surveillance system to evaluate the efficacy of the cleaning and disinfection procedure, and to trace disinfection problems to individual endoscopes or washer-disinfectors.

Methods: Our surveillance protocol included anterograde and retrograde sampling, a decision algorithm, genetic fingerprinting, and scanning electron microscopy.

Mapping the pathways to staphylococcal pathogenesis by comparative secretomics.

The gram-positive bacterium Staphylococcus aureus is a frequent component of the human microbial flora that can turn into a dangerous pathogen. As such, this organism is capable of infecting almost every tissue and organ system in the human body. It does so by actively exporting a variety of virulence factors to the cell surface and extracellular milieu.