Ajugamarin L2

Robust Alternating Low-Rank Representation by joint Lp- and L2,p-norm minimization.[Pubmed:28987977]

Neural Netw. 2017 Dec;96:55-70.

We propose a robust Alternating Low-Rank Representation (ALRR) model formed by an alternating forward-backward representation process. For forward representation, ALRR first recovers the low-rank PCs and random corruptions by an adaptive local Robust PCA (RPCA). Then, ALRR performs a joint Lp-norm and L2,p-norm minimization (0

Posterior Epidural Herniation of a Lumbar Disk Fragment at L2-3 That Mimicked an Epidural Hematoma.[Pubmed:29017311]

Korean J Spine. 2017 Sep;14(3):115-117.

Lumbar disk herniation is common. Because of the posterior longitudinal ligament, migration usually occurs into the ventral epidural space. Rarely, fragments migrate into the dorsal epidural space. A 57-year-old man presented with lower back pain and weakness on right hip flexion and right knee flexion. He had lower back pain 1 day previously and received a transforaminal epidural block at a local hospital. The next day, he reported weakness of the right lower extremity. Lumbar spine magnetic resonance imaging revealed a dorsal epidural lesion with compression of the thecal sac at L2-3. Initial differential diagnoses included epidural hematoma after the block, neoplasm, and a sequestrated disk. Posterior lumbar decompression was performed. The lesion was identified intraoperatively as a large herniated disk fragment. Posterior epidural herniation of a lumbar disk fragment is rare and may be difficult to diagnose preoperatively. It may present as a variety of clinical scenarios and, as in this case, may mimic epidural hematoma.

Comprehensive Morpho-Electrotonic Analysis Shows 2 Distinct Classes of L2 and L3 Pyramidal Neurons in Human Temporal Cortex.[Pubmed:28968789]

Cereb Cortex. 2017 Nov 1;27(11):5398-5414.

There have been few quantitative characterizations of the morphological, biophysical, and cable properties of neurons in the human neocortex. We employed feature-based statistical methods on a rare data set of 60 3D reconstructed pyramidal neurons from L2 and L3 in the human temporal cortex (HL2/L3 PCs) removed after brain surgery. Of these cells, 25 neurons were also characterized physiologically. Thirty-two morphological features were analyzed (e.g., dendritic surface area, 36 333 +/- 18 157 mum2; number of basal trees, 5.55 +/- 1.47; dendritic diameter, 0.76 +/- 0.28 mum). Eighteen features showed a significant gradual increase with depth from the pia (e.g., dendritic length and soma radius). The other features showed weak or no correlation with depth (e.g., dendritic diameter). The basal dendritic terminals in HL2/L3 PCs are particularly elongated, enabling multiple nonlinear processing units in these dendrites. Unlike the morphological features, the active biophysical features (e.g., spike shapes and rates) and passive/cable features (e.g., somatic input resistance, 47.68 +/- 15.26 MOmega, membrane time constant, 12.03 +/- 1.79 ms, average dendritic cable length, 0.99 +/- 0.24) were depth-independent. A novel descriptor for apical dendritic topology yielded 2 distinct classes, termed hereby as "slim-tufted" and "profuse-tufted" HL2/L3 PCs; the latter class tends to fire at higher rates. Thus, our morpho-electrotonic analysis shows 2 distinct classes of HL2/L3 PCs.

Neural changes underlying early stages of L2 vocabulary acquisition.[Pubmed:28983152]

J Neurolinguistics. 2016 Nov;40:55-65.

Research has shown neural changes following second language (L2) acquisition after weeks or months of instruction. But are such changes detectable even earlier than previously shown? The present study examines the electrophysiological changes underlying the earliest stages of second language vocabulary acquisition by recording event-related potentials (ERPs) within the first week of learning. Adult native English speakers with no previous Spanish experience completed less than four hours of Spanish vocabulary training, with pre- and post-training ERPs recorded to a backward translation task. Results indicate that beginning L2 learners show rapid neural changes following learning, manifested in changes to the N400 - an ERP component sensitive to lexicosemantic processing and degree of L2 proficiency. Specifically, learners in early stages of L2 acquisition show growth in N400 amplitude to L2 words following learning as well as a backward translation N400 priming effect that was absent pre-training. These results were shown within days of minimal L2 training, suggesting that the neural changes captured during adult second language acquisition are more rapid than previously shown. Such findings are consistent with models of early stages of bilingualism in adult learners of L2 (e.g. Kroll and Stewart's RHM) and reinforce the use of ERP measures to assess L2 learning.

A novel candidate HPV vaccine: MS2 phage VLP displaying a tandem HPV L2 peptide offers similar protection in mice to Gardasil-9.[Pubmed:28939477]

Antiviral Res. 2017 Nov;147:116-123.

Human papillomaviruses (HPVs) cause approximately 5% of cancer cases worldwide. Fortunately, three prophylactic vaccines have been approved to protect against HPV infections. Gardasil-9, the most recent HPV vaccine, is predicted to offer protection against the HPV types that cause approximately 90% of cervical cancer, 86% of HPV-associated penile cancers, and approximately 93% of HPV-associated head & neck cancers. As an alternative to Gardasil-9, we developed and tested a novel candidate vaccine targeting conserved epitopes in the HPV minor capsid protein, L2. We displayed a tandem HPV31/16L2 peptide (amino acid 17-31) or consensus peptides from HPV L2 (amino acid 69-86 or 108-122) on the surface of bacteriophage MS2 virus-like particles (VLPs). Mice immunized with the MS2 VLPs displaying the tandem peptide or immunized with a mixture of VLPs (displaying the tandem peptide and consensus peptide 69-86) elicited high titer antibodies against individual L2 epitopes. Moreover, vaccinated mice were protected from cervicovaginal infection with HPV pseudoviruses 16, 31, 45, 58 and sera from immunized mice neutralized HPV pseudoviruses 18 and 33 at levels similar to mice immunized with Gardasil-9. These results suggest that immunization with a tandem, L2 peptide or a low valency mixture of L2 peptide-displaying VLPs can provide broad protection against multiple HPV types.