Biomedical subjects
Publications and source records attributed to James Lawrence.
The preparation of a series of N-hydroxy peptides is described, along with their acylation on the oxygen of the pseudopeptide bond. Nineteen N-acyloxy peptides, first examples of this new class of pseudopeptides, were thus synthesized; they present a range of acyl groups, including N-protected amino acyl groups. Possibilities of elongation for these pseudopeptides were also investigated.
Acetylsalicylic acid (aspirin; 2-acetoxybenzoic acid) has been used for >100 years for pain relief and to treat inflammatory conditions and fevers. More recently, regular intake has been associated with decreased incidence of certain cancers, particularly colon cancer. After absorption aspirin is very rapidly hydrolysed to salicylic acid (2-hydroxybenzoic acid). The anti-cancer effects of aspirin may be a result of salicylic acid reducing the transcription of prostaglandin H(2)-synthase and thereby the synthesis of pro-inflammatory and potentially-neoplastic prostaglandins. Salicylic acid is widely present in plants and functions as a hormonal mediator of the systemic acquired resistance response to pathogen attack and environmental stress. Thus, it is present in a large range of fruit, vegetables, herbs and spices of dietary relevance. Consequently, the recognised effect of consuming fruit and vegetables on lowering risk of colon cancer may be partly attributable to salicylates in plant-based foods. The present review discusses which types of fruit and vegetables are the richest source of salicylates and whether they are sufficiently released from the food matrix to modify the key cellular events associated with the pathogenesis of colon cancer.
The prevalence of type 2 diabetes is rising rapidly worldwide. Evidence suggests that between one third and one half of cases are undiagnosed and patients may have preclinical disease for as long as 12 years. At diagnosis, 50% of patients have microvascular complications (retinopathy, neuropathy, or nephropathy) and patients have twice the risk of macrovascular disease compared to the background population. Screening for type 2 diabetes would allow earlier recognition of cases, with the potential to intervene earlier in the disease course, but whether this would result in improved long-term outcomes is unknown. The debate continues about who should be considered for screening, how we should screen, and whether we should screen for diabetes at all. The authors review the evidence, particularly in light of the recent position statement on diabetes screening published by the American Diabetes Association. If we do start screening for diabetes, one of the major challenges ahead is to ensure resources are in place to allow optimization of treatment for the increasing number of patients. This is important both in those found to have diabetes and in those with lesser degrees of glucose intolerance who are at high risk of developing diabetes and are at increased risk of macrovascular disease.