Purpose
Minimizing post-operational neurological deficits as a result of brain surgery has been one of the most pertinent endeavours of neurosurgical research. Studies have utilised fMRIs, EEGs and ...MEGs in order to delineate and establish eloquent areas, however, these methods have not been utilized by the wider neurosurgical community due to a lack of clinical endpoints. We sought to ascertain if there is a correlation between graph theory metrics and the neurosurgical notion of eloquent brain regions. We also wanted to establish which graph theory based nodal centrality measure performs the best in predicting eloquent areas.
Methods
We obtained diffusion neuroimaging data from the Human Connectome Project (HCP) and applied a parcellation scheme to it. This enabled us to construct a weighted adjacency matrix which we then analysed. Our analysis looked at the correlation between PageRank centrality and eloquent areas. We then compared PageRank centrality to eigenvector centrality and degree centrality to see what the best measure of empirical neurosurgical eloquence was.
Results
Areas that are considered neurosurgically eloquent tended to be predicted by high PageRank centrality. By using summary scores for the three nodal centrality measures we found that PageRank centrality best correlated to empirical neurosurgical eloquence.
Conclusion
The notion of eloquent areas is important to neurosurgery and graph theory provides a mathematical framework to predict these areas. PageRank centrality is able to consistently find areas that we consider eloquent. It is able to do so better than eigenvector and degree central measures.
We conducted a genome-wide association study of male breast cancer comprising 823 cases and 2,795 controls of European ancestry, with validation in independent sample sets totaling 438 cases and 474 ...controls. A SNP in RAD51B at 14q24.1 was significantly associated with male breast cancer risk (P = 3.02 × 10(-13); odds ratio (OR) = 1.57). We also refine association at 16q12.1 to a SNP within TOX3 (P = 3.87 × 10(-15); OR = 1.50).
Individuals with medically diagnosed knee osteoarthritis (OA) participated in a randomized, double-blind study to investigate the effects of a high-rosmarinic acid (rosA) spearmint tea. Sixty-two ...participants were randomized by sex and screening pain score to consume tea brewed from a high-rosA spearmint variety or a commercially available spearmint twice daily for 16 weeks. Pain, quality of life (QoL), and physical function at baseline and week 16 were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short-Form 36-item Health Survey (SF-36), 6-minute walk test (6MWT), and stair climb test (SCT). Data from 46 participants (mean age=60.7; BMI=32.9 kg/m(2)) were analyzed. Pain score significantly decreased from week 0 to 16 for the high-rosA group but not for the control group and scores for stiffness and physical disability significantly decreased from week 0 to 16 for both groups. Increased QoL score on the bodily pain index in the SF-36 was observed at week 16 within the high-rosA group only, although no significant differences were observed between the groups. A nonsignificant improvement was observed in the 6MWT at week 16 in the high-rosA group only. There were no changes in the SCT for either group. Therefore, 16-week daily consumption of the high-rosA and commercial spearmint teas significantly improved stiffness and physical disability scores in adults with knee OA, but only the high-rosA tea significantly decreased pain. Consumption of high-rosA tea warrants further consideration as a potential complementary therapy to reduce pain in OA.
NCT01380015.
Graph theory is a promising mathematical tool to study the connectome. However, little research has been undertaken to correlate graph metrics to functional properties of the brain. In this study, we ...report a unique association between the strength of cortical regions and their function.
Eight structural graphs were constructed within DSI Studio using publicly available imaging data derived from the Human Connectome Project. Whole-brain fiber tractography was performed to quantify the strength of each cortical region comprising our atlas.
Rank-order analysis revealed 27 distinct areas with high average strength, several of which are associated with eloquent cortical functions. Area 4 localizes to the primary motor cortex and is important for fine motor control. Areas 2, 3a and 3b localize to the primary sensory cortex and are involved in primary sensory processing. Areas V1-V4 in the occipital pole are involved in primary visual processing. Several language areas, including area 44, were also found to have high average strength.
Regions of average high strength tend to localize to eloquent areas of the brain, such as the primary sensorimotor cortex, primary visual cortex, and Broca's area. Future studies will examine the dynamic effects of neurologic disease on this metric.
•Strength is a graph metric that quantifies the number of connections to a part of cortex.•Eight structural graphs were constructed in DSI Studio to measure regional strength.•Regions of high average strength appear to correlate with eloquent functions in the brain.
Association studies in large series of breast cancer patients can be used to identify single-nucleotide polymorphisms (SNP) contributing to breast cancer susceptibility. Previous studies have ...suggested associations between variants in TP53 (R72P) and MDM2 (SNP309) and cancer risk. Data from molecular studies suggest a functional interaction between these genes. We therefore investigated the effect of TP53 R72P and MDM2 SNP309 on breast cancer risk and age at onset of breast cancer in a pooled series of 5,191 cases and 3,834 controls from the Breast Cancer Association Consortium (BCAC). Breast cancer risk was not found to be associated with the combined variant alleles odds ratio (OR), 1.00; 95% confidence interval (95% CI), 0.81-1.23. Estimated ORs were 1.01 (95% CI, 0.93-1.09) per MDM2 SNP309 allele and 0.98 (95% CI, 0.91-1.04) for TP53 R72P. Although we did find evidence for a 4-year earlier age at onset for carriers of both variant alleles in one of the breast cancer patient series of the BCAC (the German series), we were not able to confirm this effect in the pooled analysis. Even so, carriers of both variant alleles did not have different risk estimates for bilateral or estrogen receptor-positive breast cancer. In conclusion, in this large collaborative study, we did not find an association of MDM2 SNP309 and TP53 R72P, separately or in interaction, with breast cancer. This suggests that any effect of these two variants would be very small and possibly confined to subgroups that were not assessed in our present study.
To define magnetic resonance imaging (MRI) appearances of the brain in extremely preterm infants between birth and term, a sequential cohort of infants born at a gestational age <30 weeks was studied ...with a dedicated neonatal magnetic resonance scanner. Images of infants (n = 41) with a median gestational age of 27 weeks (range 23 to 29 weeks) were initially obtained at a median age of 2 days (range 1 to 20 days) and then repeatedly studied; 29 (71%) infants had MRI at a median gestational age of 43 weeks (range 38 to 52 weeks) (term MRI). On the initial MRI scan 28 of 41 infants had abnormalities: either intraventricular hemorrhage, germinal layer hemorrhage, ventricular dilatation, or diffuse and excessive high signal intensity in the white matter on T
2 -weighted images. When magnetic resonance images for preterm infants at term gestation were compared with those of infants in the control group born at term, 22 of 29 infants had dilatation of the lateral ventricles, 24 of 29 had squaring of the anterior or posterior horns of the lateral ventricles, 11 of 29 had a widened interhemispheric fissure or extracerebral space, and 22 of 29 had diffuse and excessive high signal intensity in the white matter. There were no cases of cystic periventricular leukomalacia. We conclude that MRI abnormalities are commonly seen in the brain of preterm infants on whom images are obtained within 48 hours of birth and that further abnormalities develop between birth and term. A characteristic appearance of diffuse and excessive high signal intensity in the white matter on T
2 -weighted images is associated with the development of cerebral atrophy and may be a sign of white matter disease. These MRI appearances may help account for the high incidence of neurodevelopmental impairment in extremely preterm infants. (J Pediatr 1999;135:351-7)
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