Low Internal Air Space In Plants With Crassulacean Acid Metabolism May Be An Anatomical Spandrel

Crassulacean Acid Metabolism (CAM) is a photosynthetic adaptation found in at least 38 plant families. Typically, the anatomy of CAM plants is characterised by large photosynthetic cells and a low percentage of leaf volume comprised of internal air space (% IAS). It has been suggested that reduced mesophyll conductance (gm) arising from low % IAS benefits CAM plants by preventing the movement of CO2 out of cells and ultimately minimising leakage of CO2 from leaves into the atmosphere during day-time decarboxylation. Here, we propose that low % IAS does not provide any adaptive benefit to CAM plants, because stomatal closure during phase III of CAM will result in internal concentrations of CO2 becoming saturated, meaning low gm will not have any meaningful impact on the flux of gasses within leaves. We suggest that low % IAS is more likely an indirect consequence of maximising the cellular volume within a leaf, to provide space for the overnight storage of malic acid during the CAM cycle

A Conscious Sedation Protocol for Videolaryngostroboscopy in Pediatric Patients

Objective. To determine best sedation protocol for videolaryngostroboscopy in children unable to tolerate non-sedated evaluation. Materials and Methods. Consecutive case series of 10 children with voice disturbances, unable to tolerate nonsedated videolaryngostroboscopy at an academic tertiary care children's hospital. Flexible fiberoptic videolaryngostroboscopy was performed and interpreted by pediatric otolaryngologist and speech and language pathologist. Sedation was administered with newly described protocol that allowed functional portion of evaluation. Main Outcome Measures: ability to follow commands and tolerate flexible fiberoptic videolaryngostroboscopy. Secondary Outcome Measures: total phonation time, complications, need for subsequent videolaryngostroboscopic attempts, clinical outcomes, and follow-up. Results. 10 children underwent procedure under conscious sedation. 9/10 children were able to perform simple tasks and maintain adequate phonation time to complete stroboscopic exam. 1/10 patients failed to complete exam because of crying during entire exam. Mean exam time was 2 minutes 52 seconds (SD 86 seconds), phonation time is 1 minute 44 seconds (SD 60 seconds), and number of tasks completed was 10.5 (SD 8.6). Conclusions. Conscious sedation for videolaryngostroboscopy can be safely and effectively performed in children unable to comply with nonsedated examination. Such studies provide valuable diagnostic information to make a diagnosis and to devise a treatment plan

Etched in the Memory.

Alan Forster, Samantha Vettese-Forster and John Borland explore the cultural value of preserving historic graffiti

Etched in the Memory.

Alan Forster, Samantha Vettese-Forster and John Borland explore the cultural value of preserving historic graffiti

Clinical Study A Conscious Sedation Protocol for Videolaryngostroboscopy in Pediatric Patients

Objective. To determine best sedation protocol for videolaryngostroboscopy in children unable to tolerate non-sedated evaluation. Materials and Methods. Consecutive case series of 10 children with voice disturbances, unable to tolerate nonsedated videolaryngostroboscopy at an academic tertiary care children's hospital. Flexible fiberoptic videolaryngostroboscopy was performed and interpreted by pediatric otolaryngologist and speech and language pathologist. Sedation was administered with newly described protocol that allowed functional portion of evaluation. Main Outcome Measures: ability to follow commands and tolerate flexible fiberoptic videolaryngostroboscopy. Secondary Outcome Measures: total phonation time, complications, need for subsequent videolaryngostroboscopic attempts, clinical outcomes, and follow-up. Results. 10 children underwent procedure under conscious sedation. 9/10 children were able to perform simple tasks and maintain adequate phonation time to complete stroboscopic exam. 1/10 patients failed to complete exam because of crying during entire exam. Mean exam time was 2 minutes 52 seconds (SD 86 seconds), phonation time is 1 minute 44 seconds (SD 60 seconds), and number of tasks completed was 10.5 (SD 8.6). Conclusions. Conscious sedation for videolaryngostroboscopy can be safely and effectively performed in children unable to comply with nonsedated examination. Such studies provide valuable diagnostic information to make a diagnosis and to devise a treatment plan

Regulation of vascular smooth muscle cell calcification by syndecan-4/FGF-2/PKCα signaling and cross-talk with TGFβ

Aims: Vascular calcification is a major cause of morbidity and mortality. Fibroblast growth factor-2 (FGF-2) plays an instructive role in osteogenesis and bone development, but its role in vascular calcification was unknown. Therefore, we investigated the involvement of FGF-2 in vascular calcification and determined the mechanism by which it regulates this process. Methods and Results: We demonstrate that FGF-2 expression is increased in vascular smooth muscle cells (VSMCs) induced to deposit a mineralized matrix by incubation with β-glycerophosphate. FGF-2 is also localized to sites of calcification within human atherosclerotic plaques. The expression of syndecan-4, a heparan sulfate proteoglycan which regulates FGF-2 signaling, is also increased in mineralizing VSMCs and co-localizes with FGF-2 in human calcified atherosclerotic plaques. Exogenous FGF-2 inhibits VSMC mineralization, and this inhibition is reduced when syndecan-4 expression is knocked-down using siRNA. Biochemical inhibition of FGFR signaling using a pan FGFR inhibitor (BGJ398) or knocking-down syndecan-4 expression in VSMCs using siRNA increases VSMC mineralization. These increases are prevented by inhibiting transforming growth factor-β (TGFβ) signaling with SB431542, suggesting cross-talk between FGF-2 and TGFβ signaling is crucial for the regulation of VSMC mineralization. Syndecan-4 can also regulate FGF-2 signaling directly via protein kinase Cα (PKCα) activation. Biochemical inhibition of PKCα activity using Gö6976, or siRNA-mediated suppression of PKCα expression increases VSMC mineralization; this increase is also prevented with SB431542. Finally, the ability of FGF-2 to inhibit VSMC mineralization is reduced when PKCα expression is knocked-down. Conclusion: This is the first demonstration that syndecan-4 promotes FGF-2 signaling, and in turn, suppresses VSMC mineralization by down-regulating TGFβ signaling. Our discoveries that FGF-2 and syndecan-4 expression is increased in mineralizing VSMCs and that PKCα regulates FGF-2 and TGFβ signaling in VSMCs suggests that the syndecan-4/FGF-2/TGFβ signaling axis could represent a new therapeutic target for vascular calcification

A developmental approach to diversifying neuroscience through effective mentorship practices: perspectives on cross-identity mentorship and a critical call to action.

Many early-career neuroscientists with diverse identities may not have mentors who are more advanced in the neuroscience pipeline and have a congruent identity due to historic biases, laws, and policies impacting access to education. Cross-identity mentoring relationships pose challenges and power imbalances that impact the retention of diverse early career neuroscientists, but also hold the potential for a mutually enriching and collaborative relationship that fosters the mentee\u27s success. Additionally, the barriers faced by diverse mentees and their mentorship needs may evolve with career progression and require developmental considerations. This article provides perspectives on factors that impact cross-identity mentorship from individuals participating in Diversifying the Community of Neuroscience (CNS)-a longitudinal, National Institute of Neurological Disorders and Stroke (NINDS) R25 neuroscience mentorship program developed to increase diversity in the neurosciences. Participants in Diversifying CNS were comprised of 14 graduate students, postdoctoral fellows, and early career faculty who completed an online qualitative survey on cross-identity mentorship practices that impact their experience in neuroscience fields. Qualitative survey data were analyzed using inductive thematic analysis and resulted in four themes across career levels: (1) approach to mentorship and interpersonal dynamics, (2) allyship and management of power imbalance, (3) academic sponsorship, and (4) institutional barriers impacting navigation of academia. These themes, along with identified mentorship needs by developmental stage, provide insights mentors can use to better support the success of their mentees with diverse intersectional identities. As highlighted in our discussion, a mentor\u27s awareness of systemic barriers along with active allyship are foundational for their role

2015 Research & Innovation Day Program

A one day showcase of applied research, social innovation, scholarship projects and activities.https://first.fanshawec.ca/cri_cripublications/1002/thumbnail.jp

Self-assembling peptide hydrogel for intervertebral disc tissue engineering

AbstractCell-based therapies for regeneration of intervertebral discs are regarded to hold promise for degenerative disc disease treatment, a condition that is strongly linked to lower back pain. A de novo self-assembling peptide hydrogel (SAPH), chosen for its biocompatibility, tailorable properties and nanofibrous architecture, was investigated as a cell carrier and scaffold for nucleus pulposus (NP) tissue engineering. Oscillatory rheology determined that the system would likely be deliverable via minimally invasive procedure and mechanical properties could be optimised to match the stiffness of the native human NP. After three-dimensional culture of NP cells (NPCs) in the SAPH, upregulation of NP-specific genes (KRT8, KRT18, FOXF1) confirmed that the system could restore the NP phenotype following de-differentiation during monolayer culture. Cell viability was high throughout culture whilst, similarly to NPCs in vivo, the viable cell population remained stable. Finally, the SAPH stimulated time-dependent increases in aggrecan and type II collagen deposition, two important NP extracellular matrix components. Results supported the hypothesis that the SAPH could be used as a cell delivery system and scaffold for the treatment of degenerative disc disease.Statement of SignificanceLower back pain (LBP) prevalence is widespread due to an aging population and the limited efficacy of current treatments. As LBP is strongly associated with intervertebral disc (IVD) degeneration, it is thought that cell-based therapies could alleviate LBP by repairing IVD tissue.Various natural and synthetic biomaterials have been investigated as potential IVD tissue engineering scaffolds. Self-assembling peptide hydrogels (SAPHs) combine advantages of both natural and synthetic biomaterials; for example they are biocompatible and have easily modifiable properties.The present study demonstrated that a de novo SAPH had comparable strength to the native tissue, was injectable, restored the IVD cell phenotype and stimulated deposition of appropriate matrix components. Results illustrated the promise of SAPHs as scaffolds for IVD tissue engineering