Please refer to abstract number 61. This abstract was originally submitted as a poster, and on the basis of its scientific interest and merit, was chosen by the colloquium organizers to be presented as an oral communication, as well as a poster.Please refer to abstract number 52. This abstract was originally submitted as a poster, and on the basis of its scientific interest and merit, was chosen by the colloquium organizers to be presented as an oral communication, as well as a poster.

Varicose veins are tortuous, twisted, or lengthened veins. Unless the enlargement is severe, size alone does not indicate abnormality because size can vary depending on ambient temperature and, in women, hormonal factors. In addition, normal superficial veins in a thin person may appear large, whereas varicose veins in an obese person may be hidden. Varicose veins can be classified as trunk, reticular, or telangiectasia. Telangiectasia are also referred to as spider veins, star bursts, thread veins, or matted veins. Most varicose veins are primary; only the minority are secondary to conditions such as deep vein thrombosis and occlusion, pelvic tumours, or arteriovenous fistulae. Incidence and prevalenceA study of people aged 35 to 70 years in London in 1992 concluded that the prevalence of varicose veins in men and women was 17% and 31% respectively. Although varicose veins have traditionally been considered commoner in women, a recent study from Edinburgh of people aged 18 to 64 years found that the prevalence of trunk varices was 40% in men and 32% in women. Over 80% of the total population had reticular varicosities or telangiectasia. There are few studies on the incidence of varicose veins; however, the Framingham study found that the two year incidence of varicose veins was 39.4/1000 for men and 51.9/1000 for women. Pathophysiology and risk factorsThe theory that varicose veins result from failure of valves in the superficial veins leading to venous reflux and vein dilatation has been superseded by the hypothesis that valve incompetence follows rather than precedes a change in the vein wall. Thus, the vein wall is inherently weak in varicose veins, which leads to dilatation and separation of valve cusps so that they become incompetent. This theory is strongly supported by the observation that the dilatation of varicose veins is initially distal to the valve; if the primary abnormality was descending valve incompetence, the initial dilatation should be proximal to the valve.Risk factors for varicose veins include increasing age and parity and occupations that require a lot of standing. There is no evidence that social class, smoking, or genetic makeup influence the prevalence of varicose veins. Obesity is associated with the development of varicose veins in women but not in men. SymptomsThe Edinburgh vein study recently compared the prevalence of symptoms in men and women with and without varicose veins. In men, the only symptom that was significantly associated with trunk varices was itching, whereas in women, heaviness or tension, aching, and itching were significantly associated with trunk varices. No association was found between reticular varices and lower limb symptoms in either men or women. Symptoms associated with varicose veinsx Heaviness x Tension x Aching x Itching Trunk varices are varicosities in the line of the long (top, left) or short (top, right) saphenous vein or their major branches. Reticular veins (arrow, bottom) are dilated tortuous subcutaneous veins not belonging to the main branches ...

The encapsulation of islets of Langerhans in alginate-poly-l-lysine has been proposed as a method for the immunoprotection of transplanted islets. Although several capsule compositions have been reported, there has been no published study concerning the effect of capsule composition on the severity of the foreign body reaction. Empty capsules were prepared from high mannuronic acid alginate and were coated with: (1) poly-l-lysine alone, (2) poly-l-lysine plus high guluronic acid alginate, or (3) poly-l-lysine plus high mannuronic acid alginate. The capsules were placed in the renal subcapsular space or the peritoneal cavity, and retrieved after three weeks of histological examination. The recipients were WAG/01a, nude (athymic), diabetic BB, and non-diabetes prone BB rats. The severity of reaction to the capsules was determined by measuring the thickness of the pericapsular cell infiltrate or by a scoring system. The severity of the reaction to the capsules was strain-dependent in both the renal and peritoneal sites, with the BB and nude rats displaying the most severe responses. The degree of response was not affected by capsule composition in the renal subcapsular space, but in the peritoneum, the high mannuronic acid alginate capsules provoked the weakest response, and this type of capsule will be used for future transplantation work. The infiltrating cells were characterised by immunohistochemistry and electron microscopy and found to be mostly fibroblasts and macrophages.

Multiple associations between short telomere length and vascular disease characterised by atherosclerosis suggest a possible link between telomere attrition and disease mechanisms. Further studies are warranted to validate and define the role of telomeres in vascular disease pathogenesis.

The original report on the microencapsulation of islets of Langerhans used sodium alginate and poly-L-lysine (PLL) to form the capsules. Although several alternative materials have subsequently been used with vary-mg degrees of success, it is those studies using islets encapsulated in alginate-PLL-alginate which are reviewed in detail in this article. Since the first report of islet microencapsulation, many studies have demonstrated excellent in vitro viability of encapsulated islets. However, transplantation experiments into chemically induced diabetic recipients have yielded varied results, with some studies showing good long-term graft function whilst in others grafts failed due to pericapsular fibrosis. The use of naturally occurring animal models of type 1 (insulin-dependent) diabetes has demonstrated a decline in graft function, suggesting that this presents a more complex problem to be solved than that in chemically induced diabetic recipients. Fibrosis of capsules has been the major problem causing graft failure, and this has been demonstrated to be more severe in spontaneously diabetic models. However, recent advances in alginate purification and attempts to reduce the size of the encapsulated islets are major steps towards encapsulated islet transplants becoming a viable proposition for the treatment of type 1 diabetic patients.

No abstract

In this clinic 14 per cent of leg ulcers had a significant arterial component and over half of venous ulcers may benefit from superficial venous surgery. In many ulcerated limbs, clinical assessment alone is inadequate to detect superficial reflux or previous deep vein thrombosis.

No abstract