Acute Damage to the Posterior Limb of the Internal Capsule on Diffusion Tensor Tractography as an Early Imaging Predictor of Motor Outcome after Stroke

Background and Purpose Early prediction of motor outcome is of interest in stroke management. We aimed to determine whether lesion location at DTT is predictive of motor outcome after acute stroke and whether this information improves the predictive accuracy of the clinical scores. Methods We evaluated 60 consecutive patients within 12 hours of MCA stroke onset. We used DTT to evaluate CST involvement in the MC and PMC, CS, CR, and PLIC and in combinations of these regions at admission, at day 3, and at day 30. Severity of limb weakness was assessed using the m-NIHSS (5a, 5b, 6a, 6b). We calculated volumes of infarct and FA values in the CST of the pons. Results Acute damage to the PLIC was the best predictor associated with poor motor outcome, axonal damage, and clinical severity at admission (P&.001). There was no significant correlation between acute infarct volume and motor outcome at day 90 (P=.176, r=0.485). The sensitivity, specificity, and positive and negative predictive values of acute CST involvement at the level of the PLIC for 4 motor outcome at day 90 were 73.7%, 100%, 100%, and 89.1%, respectively. In the acute stage, DTT predicted motor outcome at day 90 better than the clinical scores (R2=75.50, F=80.09, P&.001). Conclusions In the acute setting, DTT is promising for stroke mapping to predict motor outcome. Acute CST damage at the level of the PLIC is a significant predictor of unfavorable motor outcome.

Vertebrates Limb Geometry in the Simplex space

A novel metric comparison of the appendicular skeleton (fore and hind limb) ofdifferent vertebrates using the Compositional Data Analysis (CDA) methodologicalapproach it’s presented.355 specimens belonging in various taxa of Dinosauria (Sauropodomorpha, Theropoda,Ornithischia and Aves) and Mammalia (Prothotheria, Metatheria and Eutheria) wereanalyzed with CDA.A special focus has been put on Sauropodomorpha dinosaurs and the Aitchinsondistance has been used as a measure of disparity in limb elements proportions to infersome aspects of functional morphology

Can a Halo CME from the limb be geoeffective?

The probability for a halo coronal mass ejection (CME) to be geoeffective is assumed to be higher the closer the CME launch site is located to the solar central meridian. However, events far from the central meridian may produce severe geomagnetic storms, like the case in April 2000. In this work, we study the possible geoeffectiveness of full halo CMEs with the source region situated at solar limb. For this task, we select all limb full halo (LFH) CMEs that occurred during solar cycle 23, and we search for signatures of geoeffectiveness between 1 and 5 days after the first appearance of each CME in the LASCO C2 field of view. When signatures of geomagnetic activity are observed in the selected time window, interplanetary data are carefully analyzed in order to look for the cause of the geomagnetic disturbance. Finally, a possible association between geoeffective interplanetary signatures and every LFH CME in solar cycle 23 is checked in order to decide on the CME's geoeffectiveness. After a detailed analysis of solar, interplanetary, and geomagnetic data, we conclude that of the 25 investigated events, there are only four geoeffective LFH CMEs, all coming from the west limb. The geoeffectiveness of these events seems to be moderate, turning to intense in two of them as a result of cumulative effects from previous mass ejections. We conclude that ejections from solar locations close to the west limb should be considered in space weather, at least as sources of moderate disturbances.

Clinical evolution of sacral stress fractures: influence of additional pelvic fractures

To evaluate the clinical evolution of sacral stress fractures in relation to the scintigraphic pattern and the presence of additional pelvic fractures. METHODS--This was a retrospective study of 14 patients with sacral fractures. RESULTS--Six patients had additional pelvic fractures. Four bone scintigraphic patterns were found. The resolution of symptoms was longer in patients with associated pelvic fractures (30 weeks v three weeks). No relation was found between the bone scintigraphic pattern and the time of evolution. CONCLUSION--Associated pelvic fractures delay the resolution of symptoms in patients with sacral fractures, regardless of scintigraphic pattern.

Clinical evolution of sacral stress fractures: influence of additional pelvic fractures

To evaluate the clinical evolution of sacral stress fractures in relation to the scintigraphic pattern and the presence of additional pelvic fractures. METHODS--This was a retrospective study of 14 patients with sacral fractures. RESULTS--Six patients had additional pelvic fractures. Four bone scintigraphic patterns were found. The resolution of symptoms was longer in patients with associated pelvic fractures (30 weeks v three weeks). No relation was found between the bone scintigraphic pattern and the time of evolution. CONCLUSION--Associated pelvic fractures delay the resolution of symptoms in patients with sacral fractures, regardless of scintigraphic pattern.

Can a Halo CME from the limb be geoeffective?

The probability for a halo coronal mass ejection (CME) to be geoeffective is assumed to be higher the closer the CME launch site is located to the solar central meridian. However, events far from the central meridian may produce severe geomagnetic storms, like the case in April 2000. In this work, we study the possible geoeffectiveness of full halo CMEs with the source region situated at solar limb. For this task, we select all limb full halo (LFH) CMEs that occurred during solar cycle 23, and we search for signatures of geoeffectiveness between 1 and 5 days after the first appearance of each CME in the LASCO C2 field of view. When signatures of geomagnetic activity are observed in the selected time window, interplanetary data are carefully analyzed in order to look for the cause of the geomagnetic disturbance. Finally, a possible association between geoeffective interplanetary signatures and every LFH CME in solar cycle 23 is checked in order to decide on the CME's geoeffectiveness. After a detailed analysis of solar, interplanetary, and geomagnetic data, we conclude that of the 25 investigated events, there are only four geoeffective LFH CMEs, all coming from the west limb. The geoeffectiveness of these events seems to be moderate, turning to intense in two of them as a result of cumulative effects from previous mass ejections. We conclude that ejections from solar locations close to the west limb should be considered in space weather, at least as sources of moderate disturbances.

On regeneration and collateral sprouting to hind limb digits after sciatic nerve injury in the rat

This study examines the proportions of regenerative and collateral sprouting to the skin after peripheral nerve injury. Methods: In the first experimental paradigm, primary afferent neurones were pre-labelled with Diamidino Yellow (DY), injected in digit 3, followed by sciatic nerve section and repair. After three months of regeneration, digit 3 was re-injected with Fast Blue (FB) to label regernating cells. Fluoro-Gold (FG) was applied to the femoral (FEM) and musculocutaneous (MC) nervers four days later to quantify their contribution to the innveration. In the second experimental paradigm, sciatic nerve was first sectioned and repaired. Three months later, the sciatic was resected, and digit 3 injected with FB. After four more days, FEM and MC were resected and FG injected in all digits. Results: Neurones in dorsal root ganglion (DRG) L5 had a higher rate of correct reinnervation of digit 3 (44-72%) than neurones in DRG L4 (14-44%). Like in control cases, only occasional axons were traced from the FEM and MC. In the second experiment, only occasional labelled neurones appeared. Conclusions: The results indicate differences in the capacity for correct peripheral sensory reinnvervation between segmental levels and that in this model collateral sprouting was practically non-existent compared to regenerative sprouting.