Surgical e-learning: validation of multimedia web-based lectures

BACKGROUND: Distance learning has been advocated increasingly as a modern efficient method of teaching surgery. Efficiency of knowledge transfer and validity of web-based courses have not been subjected to rigorous study to date. METHODS: An entirely web-based surgical 5-week lecture course was designed. Fifty per cent of the lectures were prepared as HTML slides with voice-over while the other group was presented in the text-only form. Only written material presented was examined. The lectures were presented via an educational web module. The lecture series was balanced specifically to reduce the pre-existent knowledge bias. Web usage was estimated utilising surrogates, including the number of hits as well as log-on timing. Face validity was assessed by a standardised questionnaire. RESULTS: Eighty-eight students took part in the lecture series and subsequent examination and questionnaire. Median multiple choice questionnaire (MCQ) marks were significantly higher in the aural lecture-derived stems versus the non-aural (P = 0.012, Mann-Whitney U-test). There was widespread approval of web-based learning as an adjunct to conventional teaching. Usage rates were augmented significantly in the final week when compared to the previous 4 weeks (mean total hits weeks 1-4 +/- SEM: 100.9 +/- 9.7 and mean total hits week 5: 152.1 +/- 13.1; P < 0.001, Kruskal-Wallis). However, total hits did not correlate with overall examination results (r(2) = 0.16). The aural lectures demonstrated higher face validity than the non-aural for content and presentation (P < 0.05, Kruskal-Wallis). CONCLUSIONS: The addition of aural files to the novel web-based lecture series is face valid and results in significantly increased examination performance.     

CP-31398 restores mutant p53 tumor suppressor function and inhibits UVB-induced skin carcinogenesis in mice

Mutations in the tumor suppressor p53 are detectable in over 50% of all human malignancies. Mutant p53 protein is incapable of transactivating its downstream target genes that are required for DNA repair and apoptosis. Chronic exposure to UVB induces p53 mutations and is carcinogenic in both murine and human skin. CP-31398, a styrylquinazoline compound, restores the tumor suppressor functions of mutant forms of p53 in tumor cells. However, its effectiveness in vivo remains unclear. Here, we demonstrate that CP-31398 blocked UVB-induced skin carcinogenesis and was associated with increases in p53, p21, and BclXs. CP-31398 downregulated Bcl2, proliferating nuclear cell antigen, and cyclin D1. Activation of caspase-3 and cleavage of poly (ADP-ribose) polymerase also occurred in both tumor and perilesional skin following treatment. CP-31398 induced the expression of p53-dependent target proteins, and this was followed by apoptosis in UVB-irradiated wild-type mice but not in their p53-deficient littermates. Similar effects were observed in human skin carcinoma A431 cells expressing mutant p53. In addition, CP-31398 induced mitochondrial translocation of p53, leading to changes in mitochondrial membrane permeability pore transition (MPT) and consequent cytochrome c release in these cells. Blocking MPT diminished p53 translocation and apoptosis. These studies indicate that reconstituting p53 tumor suppressor functions in vivo by small molecular weight compounds may block the pathogenesis and progression of skin cancer.     

Colonic filiform polyposis and a malignant adenomatous polyp

We have reported a case of pseudopolyposis in the unusual form of filiform polyps in the transverse colon with an adenomatous polyp in the sigmoid colon that had a focus of malignant degeneration. The patient did not have any significant past history of inflammatory bowel disease.     

Transcatheter Pulmonary Valve Replacement With the Melody Valve in Small Diameter Expandable Right Ventricular Outflow Tract Conduits

Objectives

This study sought to evaluate the safety, feasibility, and outcomes of transcatheter pulmonary valve replacement (TPVR) in conduits ≤16 mm in diameter.

Percutaneous Pulmonary Valve Implantation‐Associated Ventricular Tachycardia in Congenital Heart Disease

Background

Percutaneous pulmonary valve implantation (PPVI) is utilized for dysfunctional right ventricular outflow tracts (RVOT) to relieve obstruction, regurgitation, and RV dysfunction. PPVI has not been reported to induce arrhythmias. This study is the first to report the incidence of ventricular tachycardia (VT) after PPVI.

Methods

This was a retrospective study of all patients who had PPVI at a single institution. All patients were admitted after PPVI for overnight telemetry monitoring. Patients with no prior history of VT and newly detected VT within 24 hours post‐PPVI were considered to have VT related to PPVI.

Results

In total, 79 patients had PPVI (age 17 ± 9 years, 66% tetralogy of Fallot/pulmonary atresia). PPVI‐related VT was detected in 6 patients (7.5%). These patients had a lower BMI (17.5 ± 2.0 vs. 23.1 ± 6.6, P = 0.04). There was no difference in age, native conduit or percutaneous valve size, or change in the minimum diameter of the RVOT from pre‐ to post‐PPVI. In the 6 patients, VT was non‐sustained and monomorphic at rates between 120 and 170. Five started on β‐blockers. No patient required surgical explantation of the valve. Over a median follow‐up of 2 years, 4 have weaned off medications and all are free of recurrence of VT with normal Holters.

Conclusions

PPVI may be associated with transient VT in the acute peri‐procedural period. Patients of smaller size may be more susceptible. All patients were managed conservatively and none of the patients had a recurrence, which is suggestive of a transient phenomenon.

     

Treatment options for metastatic renal cell carcinoma: a review

Metastatic renal cell carcinoma (RCC) has a poor overall survival. Localized RCC remains a surgical disease. About 20%-30% patients who present with limited disease at the time of nephrectomy develop metastasis. The median time to relapse after nephrectomy is 15-18 months. The maximum numbers of relapses are within the first 3 years. In metastatic RCC, immunotherapy is effective in a relatively small percentage of patients but is very toxic. In recent years, there has been an improved understanding of the biology of RCC. This has lead to the development of various agents that target ligands at the molecular level. The hypoxia inducible factor-alfa (HIF-)/ vascular endothelial growth factor (VEGF) pathway and mammalian target of rapamycin (mTOR) signal transduction pathway are targets for some of these novel agents. Recent randomized phase III trials have shown an improved outcome in patients with metastatic disease who received these targeted agents. This review deals with management of advanced and metastatic renal cell cancer with an emphasis on recently developed targeted therapies.     

The Role of Intracoronary Plaque Imaging with Intravascular Ultrasound,Optical Coherence Tomography,and Near-Infrared Spectroscopy in Patients with Coronary Artery Disease

The development of multiple diagnostic intracoronary imaging modalities has increased our understanding of coronary atherosclerotic disease. These imaging modalities, intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near-infrared spectroscopy (NIRS), have provided a method to study plaques and introduced the concept of plaque vulnerability. They are being increasingly used for percutaneous coronary intervention (PCI) optimization and are invaluable tools in research studying the pathophysiology of acute coronary syndrome (ACS), in-stent thrombosis and in-stent restenosis. IVUS has the ability to visualize the intracoronary lumen and the vessel wall and can be used to detect early atherosclerotic disease even in the setting of positive arterial remodeling. Studies supporting the use of IVUS to optimize stent deployment and apposition have shown a significant reduction in cardiovascular events. OCT provides even higher resolution imaging and near microscopic detail of plaques, restenoses, and thromboses; thus, it can identify the etiology of ACS. Ongoing trials are evaluating the role of OCT in PCI and using OCT to study stent endothelialization and neointimal proliferation. NIRS is a modality capable of localizing and quantifying lipid core burden. It is usually combined with IVUS and is used to characterize plaque composition. The benefits of NIRS in the setting of ACS have been limited to case reports and series. The utilization of all these intracoronary imaging modalities will continue to expand as their indications for clinical use and research grow. Studies to support their use for PCI optimization resulting in improved outcomes with potential to prevent downstream events are ongoing.     

Interferon Regulatory Factor 5 Gene Polymorphisms in Iranian Women with Unexplained Recurrent Pregnancy Loss

Objective: This study aimed to examine the association of three functional IRF5 rs10954213, rs3757385, and rs41298401 polymorphisms with susceptibility to unexplained recurrent pregnancy loss (RPL) among Iranian women from south of Iran.

Methods: 176 women with unexplained RPL and 173 healthy postmenopausal controls were enrolled in this case-control study. Genotyping of the polymorphisms rs10954213 and rs3757385 was carried out using touchdown tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS PCR), and polymorphism rs41298401 was typed using PCR-restriction fragment length polymorphism (PCR-RFLP).

Results: Genotype frequencies were significantly different between RPL cases and controls regarding AG heterozygote genotype of rs10954213, GT genotype of rs3757385, and GG genotype of rs41298401. In addition, allele variants (G for rs10954213, T for rs3757385, and G for rs41298401) showed protective role against RPL, while GG haplotype of two first variants was shown to be a susceptibility factor for the disease.

Conclusion: These data provide the first evidence, to our knowledge, of the protective role of the studied IRF5 gene polymorphisms against unexplained RPL among Iranian women from south of Iran.