The Use of E-Learning in Peyton's 4-Step Approach: Evaluation of Facial Computed Tomography Scans.

Imparting procedural skills is challenging. Peyton's approach is an effective face-to-face teaching technique increasingly used in complex skills training. Institutions are beginning to incorporate online training as part of their procedural curriculum. We developed E-Peyton's to employ Peyton's approach through an electronic learning platform. The efficacy of E-Peyton's approach in teaching the interpretation of facial computed tomography (CT) scans is evaluated in this study. Naïve learners (n=41) were randomized into 2 groups based on teaching techniques employed: E-Peyton's (n=20) and Peyton's (n=21) approaches. The distance between the infraorbital margin and the posterior ledge was measured using a 3-part standardized measuring protocol on OsiriX. Twenty measurements were assessed for accuracy against the benchmark (±2 mm) at week 0 and week 1. Training durations were compared. Questionnaires were administered before and after the study to identify learners' acceptance of teaching techniques and their confidence in interpreting facial CT scans. Learners in both teaching techniques had comparable skills retention. Gap scores indicate significant improvement in learner's confidence levels regardless of teaching technique (P<0.05). Both teaching techniques were well-accepted by learners. E-Peyton's and Peyton's approaches required a similar training duration. The COVID-19 pandemic highlights the importance of effective remote learning platforms. E-Peyton's approach is comparable to that of Peyton's in all areas of assessment. E-Peyton's approach effectively automates Peyton's approach, allowing for standardized, high-quality procedural skills training while reducing manpower burden.

Boosted abscopal effect from radiotherapy and pembrolizumab in anaplastic thyroid cancer: a mini-review and case report.

BACKGROUND: The abscopal effect, in which radiation induces a systemic anti-tumour immune response, has been demonstrated with radiotherapy. Immunotherapy boosts the abscopal effect by facilitating the immune response to radiation. Radiotherapy and programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) blockade has resulted in the boosted abscopal effect in solid cancers, but its role in anaplastic thyroid cancer (ATC) is unknown. In this mini-review, we describe the abscopal effect and summarise its proposed underlying mechanisms. We then present a potential case of boosted abscopal effect in ATC. CASE DESCRIPTION: In our case presentation, we describe a 51-year-old female who presented with 3 weeks of rapidly enlarging thyroid mass. Examination revealed a 3-cm thyroid nodule which was Bethesda V on fine needle aspiration cytology (FNAC). Intraoperatively, there was a gross extrathyroidal extension into the cricoid cartilage. After total thyroidectomy, post-operative histopathology showed widely invasive follicular thyroid cancer with anaplastic transformation (>50%). Immunohistochemistry showed high PD-L1 expression [combined positive score (CPS) >70%]. Due to residual cricoid cartilage disease and several peri-hilar and lung metastases on positron emission tomography-computed tomography (PET-CT) scan, she underwent post-operative palliative radiotherapy and pembrolizumab. After two cycles of pembrolizumab, repeat PET-CT scan showed complete response (CR) of local and distant disease. She remained well for 32 months, before recent discovery of a right mandible bony metastasis planned for radiotherapy. CONCLUSIONS: This case demonstrates exceptional response to radiotherapy and anti-PD-1 immunotherapy in ATC, potentially illustrating the first known abscopal effect in ATC with this treatment.

Mapping the Posterior Ledge and Optic Foramen in Orbital Floor Blowout Fractures.

Background The posterior ledge (PL) is a vital structure that supports the implant posteriorly during orbital floor reconstruction. This study describes a technique for mapping the PL in relation to the infraorbital margin (IM) in patients with orbital floor blowout fractures. This study establishes the location of the optic foramen in relation to the PL. Methods Facial computed tomography (FCT) scans of 67 consecutive patients with isolated orbital floor blowout fractures were analyzed using Osirix. Planes of reference for orbital fractures, a standardized technique for performing measurements on FCT, was used. Viewed coronally, the orbit was divided into seven equal sagittal slices (L1 laterally to L7 medially) with reference to the midorbital plane. The distances of PL from IM and location of optic foramen were determined. Results The greatest distance to PL is found at L5 (median: 30.1 mm, range: 13.5-37.1 mm). The median and ranges for each slice are as follows: L1 (median: 0.0 mm, range: 0.0-19.9 mm), L2 (median: 0.0 mm, range: 0.0-21.5 mm), L3 (median: 15.8 mm, range: 0.0-31.7 mm), L4 (median: 26.1 mm, range: 0.0-34.0 mm), L5 (median: 30.1 mm, range: 13.5-37.1 mm), L6 (median: 29.0 mm, range: 0.0-36.3 mm), L7 (median: 20.8 mm, range: 0.0-39.2 mm). The median distance of the optic foramen from IM is 43.7 mm (range: 37.0- 49.1) at L7. Conclusion Distance to PL from IM increases medially until the L5 before decreasing. A reference map of the PL in relation to the IM and optic foramen is generated. The optic foramen is located in close proximity to the PL at the medial orbital floor. This aids in preoperative planning and intraoperative dissection.

Secretive derived from hypoxia preconditioned mesenchymal stem cells promote cartilage regeneration and mitigate joint inflammation via extracellular vesicles.

Secretome derived from mesenchymal stem cells (MSCs) have profound effects on tissue regeneration, which could become the basis of future MSCs therapies. Hypoxia, as the physiologic environment of MSCs, has great potential to enhance MSCs paracrine therapeutic effect. In our study, the paracrine effects of secretome derived from MSCs preconditioned in normoxia and hypoxia was compared through both in vitro functional assays and an in vivo rat osteochondral defect model. Specifically, the paracrine effect of total EVs were compared to that of soluble factors to characterize the predominant active components in the hypoxic secretome. We demonstrated that hypoxia conditioned medium, as well as the corresponding EVs, at a relatively low dosage, were efficient in promoting the repair of critical-sized osteochondral defects and mitigated the joint inflammation in a rat osteochondral defect model, relative to their normoxia counterpart. In vitro functional test shows enhancement through chondrocyte proliferation, migration, and matrix deposition, while inhibit IL-1ß-induced chondrocytes senescence, inflammation, matrix degradation, and pro-inflammatory macrophage activity. Multiple functional proteins, as well as a change in EVs' size profile, with enrichment of specific EV-miRNAs were detected with hypoxia preconditioning, implicating complex molecular pathways involved in hypoxia pre-conditioned MSCs secretome generated cartilage regeneration.

Managing the Heterogeneity of Mesenchymal Stem Cells for Cartilage Regenerative Therapy: A Review.

Articular cartilage defects commonly result from trauma and are associated with significant morbidity. Since cartilage is an avascular, aneural, and alymphatic tissue with a poor intrinsic healing ability, the regeneration of functional hyaline cartilage remains a difficult clinical problem. Mesenchymal stem cells (MSCs) are multipotent cells with multilineage differentiation potential, including the ability to differentiate into chondrocytes. Due to their availability and ease of ex vivo expansion, clinicians are increasingly applying MSCs in the treatment of cartilage lesions. However, despite encouraging pre-clinical and clinical data, inconsistencies in MSC proliferative and chondrogenic potential depending on donor, tissue source, cell subset, culture conditions, and handling techniques remain a key barrier to widespread clinical application of MSC therapy in cartilage regeneration. In this review, we highlight the strategies to manage the heterogeneity of MSCs ex vivo for more effective cartilage repair, including reducing the MSC culture expansion period, and selecting MSCs with higher chondrogenic potential through specific genetic markers, surface markers, and biophysical attributes. The accomplishment of a less heterogeneous population of culture-expanded MSCs may improve the scalability, reproducibility, and standardisation of MSC therapy for clinical application in cartilage regeneration.

In vitro propagation of Acacia mangium and A. mangium × A. auriculiformis.

Acacia mangium and A. mangium × A. auriculiformis hybrids have gained an increasing interest in reafforestation programs under the humid tropical conditions, mainly for pulpwood production. This is due to their impressive growth on acid and degraded soils, as well as their capability to restore soil fertility thanks to their natural nitrogen-fixing ability. It is crucial to develop efficient methods for improving the genetic quality and the mass production of the planting stocks of these species. In this regard, in vitro micropropagation is well suited to overcome the limitations of more conventional techniques for mass propagating vegetatively selected juvenile, mature, or even transgenic genotypes. Micropropagation of A. mangium either from seeds or from explants collected from outdoors is initiated on Murashige and Skoog (MS) basal medium supplemented with 4.4 µM BA. Microshoot cultures produced by axillary budding are further developed and maintained by regular subcultures every 60 days onto fresh MS culture medium added with 2.2 µM BA + 0.1 µM NAA. This procedure enhances the organogenic capacity for shoot multiplication by axillary budding, with average multiplication rates of 3-5 every 2 months, as well as for adventitious rooting. The rooting is initiated on Schenk and Hildebrandt culture medium containing 4 µM IAA. The maintenance of shoot cultures in total darkness for 3 weeks increases the rooting rates reaching more than 70%. The hybrid A. mangium × A. auriculiformis genotypes are subcultured at 2-month intervals with an average multiplication rate of 3 and rooting rates of 95-100% on a half-strength MS basal medium containing 1.1 µM NAA. The rooted microshoots are transferred to ex vitro controlled conditions for acclimatization and further growth, prior to transfer to the field, or use as stock plants for cost-effective and true-to-type mass production by rooted cuttings.

Bradyrhizobia nodulating the Acacia mangium x A. auriculiformis interspecific hybrid are specific and differ from those associated with both parental species.

In the context of an increasing utilization of the interspecific hybrid Acacia mangium x A. auriculiformis as a plantation tree in the tropical humid zone, its symbiotic characterization was carried out in comparison with that of its two parental species. Rhizobium strains of diverse geographical origins were isolated from root nodules of the hybrid and its parents. Almost all Acacia hybrid isolates were fast growing on yeast extract-mannitol medium, in contrast to those isolated from both parental species, which were mostly slow growing. The rhizobium strains were characterized through partial sequencing of the rRNA operon. In the phylogenetic tree, almost all strains isolated from the hybrid were grouped together in a clade close to Bradyrhizobium japonicum, while all strains isolated from both parental species were close to Bradyrhizobium elkanii. Inoculation experiments performed under in vitro or greenhouse conditions showed that all strains were infective with their original hosts but exhibited very variable degrees of effectivity according to the host plant tested. Thus, homologous strain-host associations were more effective than heterologous ones. This shows that there is still a high potential for isolating and testing new strains from hybrids to be used as inoculants in the context of large-scale afforestation programs.