Healthy subjects will be used in the study to remove bias from associated pathology/comorbidity.
One group of male volunteers of 60-80 years of age will be used for the pilot study.
There will be two groups for the main study: one male and one female group (age-matched equivalent groups).
Females will be post-menopausal with the menarche at least 1 year previously and not taking hormone replacement therapy.
No infection with Hepatitis B, C, non A/B virus or HIV.
No pregnancy or lactating females.
Must not be diabetic.
Must not be a smoker; or ex-smoker of greater than 5 per day for over one year.
Must not be on any regular medication, for example: oral/topical/intra-articular corticosteroids, NSAIDSs, immunosuppressives, chemotherapeutic agents, anti-hypertensives, vasodilators, anti-arthritic agents (gold, azathioprine), antibiotics, and insulin/biguanides/sulphonylureas.
Must not be taking oral contraceptive or HRT (oral or implant) (main study only).
No history of cardiovascular disease, malignancy, stroke, inflammatory bowel disease, Alzheimer's disease, or pulmonary fibrosis/sarcoid/CAPD.
No presence of anemia, leukocytosis, bleeding disorder, or abnormal renal/liver function.
No known keloid former or previous evidence of hypertrophic scarring.
No presence of skin disorders such as venous ulcers, psoriasis, eczema or lichen planus.