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Background One of the most important factors responsible for the calcific failure of bioprosthetic heart valves is glutaraldehyde cross-linking. Ethanol (EtOH) incubation after glutaraldehyde cross-linking has previously been reported to confer anti-calcification efficacy for bioprostheses. The present studies investigated the anticalcification efficacy in vivo of the novel cross-linking agent, triglycidyl amine (TGA), with or without EtOH incubation, in comparison to glutaraldehyde. Methods TGA cross-linking (+/− EtOH) was used to prepare porcine aortic valves for both rat subdermal implants and sheep mitral valve replacements, for comparisons with glutaraldehyde-fixed controls. Thermal denaturation temperature (Ts), an index of cross-linking, cholesterol extraction, and hydrodynamic properties were quantified. Explant endpoints included quantitative and morphologic assessment of calcification. Results Ts after TGA were intermediate between unfixed and glutaraldehyde-fixed. EtOH incubation resulted in almost complete extraction of cholesterol from TGA or glutaraldehyde-fixed cusps. Rat subdermal explants (90days) demonstrated that TGA-EtOH resulted in a significantly greater level of inhibition of calcification than other conditions. Thus, TGA-ethanol stent mounted porcine aortic valve bioprostheses were fabricated for comparisons with glutaraldehyde-pretreated controls. In hydrodynamic studies, TGA-EtOH bioprostheses had lower pressure gradients than glutaraldehyde-fixed. TGA-ethanol bioprostheses used as mitral valve replacements in juvenile sheep (150 days) demonstrated significantly lower calcium levels in both explanted porcine aortic cusp and aortic wall samples compared to glutaraldehyde-fixed controls. However, TGA-EtOH sheep explants also demonstrated isolated calcific nodules and intracuspal hematomas. Conclusions TGA-EtOH pretreatment of porcine aortic valves confers significant calcification resistance in both rat subdermal and sheep circulatory implants, but with associated structural instability.

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Postmenopausal bleeding is a common presentation in primary care. There is great emphasis placed on rapid referral for investigation to exclude endometrial malignancy, and it is the most common symptom for which women are referred to gynaecological rapid access clinics. However, it is widely accepted that only approximately 10% of patients at a postmenopausal bleed clinic will have cancer. Endometrial cancer is now often easily treatable with laparoscopic surgery, and certain pre-malignant changes can be managed with an intrauterine system, so it is important to deal with this common presentation effectively, while also knowing about the frequent causes.

Oncocytomas are rare tumours, usually occurring in the salivary glands, but may very occasionally occur in other sites. The authors present a skull base oncocytoma as a rare cause of spontaneous epistaxis. Following diagnosis through imaging and intranasal biopsy, the patient opted for annual surveillance instead of active treatment and made a full recovery nonetheless. Skull base oncocytoma is a rare tumour that may result in otherwise common symptomatology. While excision is the mainstay of management, active surveillance may be a viable alternative for select patients.