fMRI memory assessment in healthy subjects: a new approach to view lateralization data at an individual level

We present a comprehensive and clinically applicable fMRI test—including both a verbal and a visuospatial task—for assessment of hemispheric specific memory in the medial temporal lobe (MTL). fMRI data was collected from 15 healthy right-handed volunteers. Whole-brain activation was analyzed as well as activation in two regions of interest: the MTL and the anterior speech area. Laterality indices (LI) and LI-curves were calculated using the LI toolbox of Wilke and Lidzba, 2007. The fMRI paradigms successfully visualized memory-related activity in the MTL, the verbal memory measure also provided information of language lateralization. Eleven subjects showed left lateralized verbal encoding in the MTL, visuospatial memory activation was divided equally between left and right, and 14/15 subjects had left lateralized language. Lateralization data at the group level were consistent with previous studies, but a variety of activation effects were found at the individual level indicating differences in strategy during verbal and visuospatial processing. Further studies using the presented method are needed to determine its clinical usefulness.     

Fatty acid profiles in smokers with chronic periodontitis

We hypothesized that tobacco smoke induces alterations to the 3-OH fatty acids present in lipid A in a manner consistent with a microflora of reduced inflammatory potential. Whole saliva samples and full-mouth clinical periodontal recordings were obtained from persons with (22 smokers; 15 non-smokers) and without (14 smokers; 15 non-smokers) chronic periodontitis. Clear differences in the contributions of multiple saturated 3-OH fatty acid species were noted in the group with disease compared with healthy individuals. Increases in the long-chain fatty acids associated with anaerobic bacterial periodontopathogens, particularly 3-OH-C(i17.0) (146.7%, relative to controls), were apparent. Significant reductions in the 3-OH fatty acids associated with the consensus (high potency) enteric LPS structure (3-OH-C(12.0) and 3-OH-C(14.0); 33.3% and 15.8% reduction, respectively) were noted in smokers compared with non-smokers with chronic periodontitis. Thus, smoking is associated with specific structural alterations to the lipid-A-derived 3-OH fatty acid profile in saliva that are consistent with an oral microflora of reduced inflammatory potential. These findings provide much-needed mechanistic insight into the established clinical conundrum of increased infection with periodontal pathogens but reduced clinical inflammation in smokers.     

Periarticular fractures around the hip and knee: fix or replace?

The number of periarticular fragility fractures around the hip and knee is increasing. If surgical treatment is indicated, open reduction and internal fixation or replacement can often be viable options. In contrast to secondary replacement, the use of replacement in the acute stage might be advantageous because early rehabilitation and weightbearing can be initiated. This article describes the current literature related to internal fixation or primary replacement in periarticular fractures around the hip and knee.