Feasibility of delivering foot and ankle surgical courses in a partnership in Eastern, Central and Sothern Africa.

BACKGROUND: Foot and ankle pathology if not treated appropriately and in a timely manner can adversely affect both disability and quality adjusted life years. More so in the low- and middle-income countries where ambulation is the predominant means of getting around for the majority of the population in order to earn a livelihood. This has necessitated the equipping of the new generation of orthopaedic surgeons with the expertise and skills set to manage these conditions. To address this need, surgeons from the British Orthopaedic Foot & Ankle Society (BOFAS) and College of Surgeons of Eastern, Central and Southern Africa (COSECSA) transferred the "Principles of Foot and Ankle Surgery" course to an African regional setting. The course was offered to surgical trainees from 14-member countries of the COSECSA region and previously in the UK. The faculty was drawn from practicing surgeons experienced in both surgical education and foot and ankle surgery. The course comprises didactic lectures, case-based discussions in small groups, patient evaluations and guided surgical dissections on human cadavers. It was offered free to all participants. The feasibility of the course was evaluated using the model defined by Bowen considering the eight facets of acceptability, demand, implementation, practicality, adaptation, integration, expansion and limited efficacy. At the end of the course participants were expected to give verbal subjective feedback and objective feedback using a cloud based digital feedback questionnaire. The course content was evaluated by the participants as "Poor", "Below average", "Average", "Good" and "Excellent", which was converted into a value from 1-5 for analysis. The non-parametric categorical data was analysed using the Two-sample Wilcoxon rank-sum (Mann-Whitney) test, and significance was considered to be p < 0.05. RESULTS: Six courses in total were held between 2018 and 2020. Three in the UK and three in the COSECSA region. There were 78 participants in the three UK courses and 96 in the three courses run in the COSECSA region. Hundred percent of the UK participants and 97% of the COSECSA participants completed the feedback. Male to female ratio was 4:1 for the UK courses and 10:1 for the COSECSA Courses. In both regions all the participants responded that they would recommend the course to their colleagues. Among the COSECSA participants 91% reported that the course was pitched at the right level, which is similar to the 89% of the UK participants (p = 0.28). CONCLUSION: The BOFAS Principles of Foot and Ankle Surgery course design provides core knowledge, with an emphasis on clinical examination techniques of the foot and ankle, while at the same time, caters for the anticipated difference in the local clinical case mix and resources. This study establishes that by attending the course surgical trainees can achieve their learning goals in foot and ankle surgery with the same high quality qualitative and quantitative feedback in both regions. This would improve their clinical practice and confidence. The multifaceted approach adopted in this course blending didactic teaching, small group discussions, interactive sessions, case-based discussions, cadaveric surgical skills training printed educational materials and feedback helped fulfil these educational objectives. Working in partnership with local expert orthopaedic surgeons from a number of Sub-Saharan countries, was key to adapting the course to local pathology and the COSECSA setting.

Dynamics of neutrophil aggregation in couette flow revealed by videomicroscopy: effect of shear rate on two-body collision efficiency and doublet lifetime.

During inflammation, neutrophil capture by vascular endothelial cells is dependent on L-selectin and beta(2)-integrin adhesion receptors. One of us (S.I.S.) previously demonstrated that homotypic neutrophil aggregation is analogous to this process in that it is also mediated by these receptors, thus providing a model for studying the dynamics of neutrophil adhesion. In the present work, we set out to confirm the hypothesis that cell-cell adhesion via selectins serves to increase the lifetimes of neutrophil doublets formed through shear-induced two-body collisions. In turn, this would facilitate the engagement of more stable beta(2)-integrin bonds and thus increase the two-body collision efficiency (fraction of collisions resulting in the formation of nonseparating doublets). To this end, suspensions of unstimulated neutrophils were subjected to a uniform shear field in a transparent counter-rotating cone and plate rheoscope, and the formation of doublets and growth of aggregates recorded using high-speed videomicroscopy. The dependence of neutrophil doublet lifetime and two-body collision-capture efficiency on shear rate, G, from 14 to 220 s(-1) was investigated. Bond formation during a two-body collision was indicated by doublets rotating well past the orientation predicted for break-up of doublets of inert spheres. A striking dependence of doublet lifetime on shear rate was observed. At low shear (G = 14 s(-1)), no collision capture occurred, and doublet lifetimes were no different from those of neutrophils pretreated with a blocking antibody to L-selectin, or in Ca(++)-depleted EDTA buffers. At G > or = 66 s(-1), doublet lifetimes increased, with increasing G reaching values twice those for the L-selectin-blocked controls. This correlated with capture efficiencies in excess of 20%, and, at G > or = 110 s(-1), led to the rapid formation of large aggregates, and this in the absence of exogenous chemotactic stimuli. Moreover, the aggregates almost completely broke up when the shear rate was reduced below 66 s(-1). Partial inhibition of aggregate formation was achieved by blocking beta(2)-integrin receptors with antibody. By direct observation of the shear-induced interactions between neutrophils, these data reveal that steady application of a threshold level of shear rate is sufficient to support homotypic neutrophil aggregation.

Efficient antibody diversification by gene conversion in vivo in the absence of selection for V(D)J-encoded determinants.

Antibody diversification in the bursa of Fabricius occurs by gene conversion: pseudogene-derived sequences replace homologous sequences in rearranged immunoglobulin genes. Bursal cells expressing a truncated immunoglobulin mu heavy chain, introduced by retroviral gene transfer, bypass normal requirements for endogenous surface immunoglobulin expression. Immunoglobulin light chain rearrangements in such cells undergo gene conversion under conditions where the products are not selected based on their ability to encode a functional protein. The efficiency with which gene conversion maintains a productive reading frame exceeds 97% under such non-selective conditions. By analysis of donor pseudogene usage we demonstrate that bursal cell development is not driven by a restricted set of antigenic specificities. We further demonstrate that gene conversion can restore a productive reading frame to out-of-frame VJ(L) junctions, providing a rationale for the elimination of cells containing non-productive VJ(L) rearrangements prior to the onset of gene conversion in normal bursal cell development.

Histologic evaluation of combining tetracycline and allogeneic freeze-dried bone on bone regeneration in experimental defects in baboons.

Tetracyclines (TTC) have been used both systemically and locally during periodontal bone grafting procedures, but previous work regarding the effect of TTC on new bone formation has been contradictory. The purpose of this study was to determine if the use of locally applied TTC in combination with freeze-dried bone allografts (FDBA) would enhance bone regeneration in an experimental alveolar bone osseous defect grafting system. Pre-weighed freeze-dried bone allograft particles (300-500 mu diameter) were placed in nylon mesh chambers (250 mu pore size) and rehydrated with either 10 micrograms/ml aqueous TTC or sterile distilled water. Empty chambers were used as further controls. The chambers were placed in the posterior mandible of baboons in surgically created windows. After 3 and 5 weeks, the chambers were retrieved, processed histologically, and analyzed histometrically for new bone formation. The TTC-rehydrated FDBA demonstrated much greater (greater than 5x) new bone formation than the water rehydrated FDBA. These results strongly suggest that locally-applied TTC in combination with FDBA enhances new bone formation in experimental alveolar bone defects.