Case Report: Giant choledochal cyst

We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed.     

Balloon dilatation versus surgical revision of infra-inguinal autogenous vein graft stenoses: long-term follow-up

Although infra-inguinal autogenous vein graft stenoses may be treated by balloon dilatation (PTA) or surgical revision, the optimal approach is undefined. Over the last 7 years 24 PTA procedures were performed on 37 vein graft stenoses in 19 grafts. Graft stenoses were diagnosed from 2 to 72 (mean = 17.3) months after implantation. PTA was successfully completed in 23 (96%) of the 24 procedures including 18 (95%) of the primary, and 5 (100%) of the secondary procedures. Recurrent vein graft stenosis or graft thrombosis developed in 12 (67%) grafts from 3 to 47 (mean = 12.5) months after primary PTA. Long-term patency after primary PTA was 69% at 6, 29% at 12, and 22% at 36 months; secondary patency was 81% at 6, 45% at 12, and 27% at 36 months. During the same period vein graft stenosis in 7 fem-pop and 2 fem-tib grafts were surgically revised with an initial success rate of 100%, and 2 (22%) complications. Four (44%) of these grafts occluded from 1-17 (mean 6.2) months after repair, yielding a primary 5-year patency of 62%. Although vein graft stenosis may be safely, effectively, and repeatedly treated with PTA, long-term durability appears to be superior after surgical revision.     

Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa

The objective was to test the hypothesis that the optimal cryoprotective agent for cryopreservation of human spermatozoa would be a solute for which cells have the highest plasma membrane permeability, resulting in the least amount of volume excursion during its addition and removal. To test this hypothesis, theoretical simulations were performed using membrane permeability coefficients to predict optimal procedures for the addition and removal of a cryoprotectant. Simulations were performed using data from four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide, (iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations were applied to determine approaches for the addition and removal of 1 M and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to maintain a cell volume within their osmotic tolerance limits. Based on these data, ethylene glycol was predicted to be optimal for minimizing volume excursions among the solutes evaluated. These predictions were then experimentally tested using glycerol as the control cryoprotectant and ethylene glycol as the experimental cryoprotectant. The results indicate that there was a higher (P < 0.05) recovery of motile spermatozoa after cryopreservation when using 1 M ethylene glycol than with 1 M glycerol, supporting the hypothesis that use of the cryoprotectant for which the cell has the highest permeability will result in higher cell survival.      

Improving the teaching skills of residents as tutors/facilitators and addressing the shortage of faculty facilitators for PBL modules

Background  

Residents play an important role in teaching of medical undergraduate students. Despite their importance in teaching undergraduates they are not involved in any formal training in teaching and leadership skills. We aimed to compare the teaching skills of residents with faculty in facilitating small group Problem Based Learning (PBL) sessions.     

The production of chemotactic cytokines in an allogeneic response. The role of intercellular adhesion molecule-1 and lymphocyte function-associated antigen-3.

The in vitro mixed lymphocyte reaction (MLR) is regarded as a model of responsiveness to allogeneic major histocompatibility complex antigens and has historically been used to elucidate the pathway of T lymphocyte proliferation. In addition, the MLR response may reflect activation pathways relevant in acute allograft rejection. In the present study, we have applied the MLR to examine the role of adhesion molecules intercellular adhesion molecule-1 and lymphocyte function-associated antigen-3 in the induction of tumor necrosis factor-alpha (TNF-alpha) as well as chemotactic cytokines, interleukin-8 (IL-8), monocyte chemotactic protein-1 (MCP-1) and macrophage inflammatory protein-1 alpha (MIP-1 alpha). Monoclonal antibodies to the adhesion molecules (5 micrograms/ml) were added to one-way human MLR cultures and supernatants collected at various time points. The monoclonal antibodies to the adhesion molecules significantly suppressed the proliferative response by 50 to 80%. Cytokine production, TNF-alpha (3.2 +/- 0.5 ng/ml), MIP-1 alpha (12.9 +/- 3.3 ng/ml), MCP-1 (18.8 +/- 3.4 ng/ml), and IL-8 (57 +/- 18 ng/ml) peaked on day 5 of the assay. The addition of anti-intercellular adhesion molecule-1 to the cultures suppressed TNF-alpha, MIP-1 alpha, MCP-1, and IL-8 production by 68% (1.05 +/- 0.29 ng/ml), 85% (2.0 +/- 1.2 ng/ml), 63% (6.8 +/- 2.9 ng/ml), and 47% (30.3 +/- 3.7 ng/ml), respectively. Likewise, the addition of anti-lymphocyte function-associated antigen-3 monoclonal antibody suppressed the cytokines by 78% (0.71 +/- 0.34 ng/ml), 66% (4.5 +/- 2.2 ng/ml), 52% (8.8 +/- 2.2 ng/ml), and 73% (15.7 +/- 4.4 ng/ml), respectively. Immunohistochemical staining indicated that monocytes were the primary source of the chemokines IL-8, MCP-1, and MIP-1 alpha. The addition of exogenous recombinant TNF-alpha (5 ng/ml) or recombinant IL-2 (5 units/ml) to the anti-intercellular adhesion molecule-1-treated cultures allowed the recovery of the proliferative response as well as restoration of IL-2, TNF-alpha, and IL-8, but not MCP-1 or MIP-1 alpha, indicating that both soluble and adhesion molecule signals are required for the production of the C-C family of chemokines in allogeneic responses. Thus, the events resulting in cellular proliferation and chemokine production were dependent on adhesion molecule interactions.