MR gated subtraction angiography: evaluation of lower extremities

We report the first clinical experience with a new method for projective imaging of blood vessels (angiography) using magnetic resonance. Vascular contrast is produced noninvasively by the phase response of moving protons. Diastolic and systolic gated images produce, respectively, flow signal and flow void; the difference image is a map of the pulsatile flow: an arteriogram. Preliminary studies are presented of the lower extremities of one healthy volunteer and four patients (one each with occlusive disease, soft-tissue tumor, arteriovenous malformation, and venous femoral-popliteal graft). Patient data are compared with accompanying conventional arteriograms, and the new method is discussed.     

Cross sectional study of use of alternative medicines in Chinese cancer patients

The aim of this study was to ascertain the prevalence of alternative medicine consumption in Chinese cancer patients on active conventional treatment. A cross sectional survey of 100 consecutive advanced cancer patients admitted to a cancer clinical trial referral unit were personally interviewed by their assigned oncology research nurse using a specially designed questionnaire. The results showed that 64% of our patients used indigenous Chinese medication. In all age groups except the over-70s (P = 0.043), > 50% took such medication, more female (76%) than male (57.6%) patients (P = 0.323). Patients of all educational levels (P = 0.062) and religious backgrounds (P = 0.08) consumed alternative medicines. Duration of alternative medication consumption was less than three months in 50% of patients, with costs between US$40 and 2000/month for 70% of patients. Reasons cited for alternative medication consumption was hope that it might be of some benefit to their well being or disease control, and maybe even result in a miracle cure. Sources of advice on medication were mostly from strangers (by word of mouth), family, friends, the media, and infrequently from qualified professional Chinese doctors. Reasons for discontinuing such treatment were mostly given as lack of positive effect. In conclusion, Chinese cancer patients, willingly, rampantly and non-selectively seek out and consume alternative medications, with almost total ignorance of the medication consumed, oblivious to any potential side effects, and with little subjective benefit.      

Prediction of lung function in the inadequately nourished

BACKGROUND: In animal models, nutritional deficiency leads to profound qualitative changes in the lung beyond an effect on organ size. Although lung growth is non-isotropic, predictive values for spirometric lung function in children are corrected for height alone. Prediction of lung function should consider isotropic growth and nutritional status concurrently. AIM: To establish whether nutritional status influences lung function following the exclusion of the effect of isotropic growth. METHODS: Nutritional status (weight, body mass index, mid-upper arm circumference, and subscapular and triceps skinfold thicknesses) was assessed, and lung function (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow rate (PEFR) was measured in 391 healthy school age children with normal respiratory history and examination in a rural setting in West Bengal, India. RESULTS: Lung function normalised for sitting height and stature correlated significantly with indices of nutrition in both sexes. Adding weight as an independent variable to sitting height, new reference prediction equations for FEV1, FVC, and PEFR were calculated. CONCLUSIONS: Nutritional differences influence qualitative aspects of lung development in childhood beyond simple isotropic lung growth. Prediction of lung function must take account of these differences if change as a result of disease is to be accurately measured. The identification and correction of relevant dietary deficiencies might help to improve lung function in children.     

Reference values for radial bone width and mineral content using single photon absorptiometry in healthy children aged 4 to 10 years

Bone width and mineral content were measured in 420 healthy Cambridge children aged 4 to 10 years using single photon absorptiometry. The results are expressed first in the form of standard centile charts, with additional prediction charts which provide body-size-adjusted estimates for the measurements, and interpretation centiles for comparing these estimates with the actual measurements. The values obtained are similar to those reported for American children aged five to six years after adjusting for body-size differences. We suggest that appropriate application of these prediction charts will facilitate the use of single photon absorptiometry in monitoring and treating children who have disorders of bone growth and mineralization.     

Engineering of a functional interleukin-5 monomer: a paradigm for redesigning helical bundle cytokines with therapeutic potential in allergy and asthma

Interleukin (IL) 5 specifically induces the differentiation of eosinophils which are central to the pathogenesis of allergies and asthma. Structurally, IL-5 is a unique member of the short-chain helical bundle subfamily of cytokines. In contrast to other subfamily members which fold unimolecularly into a single helical bundle, IL-5 forms a pair of helical bundles by the inter-digitation of two identical monomers covalently linked by a pair of intermolecular disulfide bonds. Although a native IL-5 monomer lacks bioactivity, we recently reported the engineering of an insertional mutant of IL-5 (designated mono5) which folds unimolecularly into a single helical bundle and has biological activity similar to that of native IL-5. Here we demonstrate no differences in signal transduction pathways utilized by mono5 and IL-5, as determined by western blot analysis of early tyrosine phosphorylation events, Jak2 activation, and mitogen-activated protein kinase activation. However, binding studies utilizing conformationally dependent neutralizing anti-IL-5 monoclonal antibodies localized a tertiary structural perturbation near the insert of mono5. This perturbation enabled localization of a limited region of the tertiary structure of IL-5 that engages the IL-5 receptor -chain. Fluorescent labeling studies further revealed that the cysteines of mono5 contained free sulfhydryl groups, thereby demonstrating that the role of the disulfide bonds of IL-5 is the structural maintenance of other functional domains. The retention of conformational epitopes by mono5, but not IL-5, under reducing conditions and the equivalent thermostability of mono5 and IL-5 despite the absence of a disulfide bond in mono5 indicated that the conformation assumed by mono5 is very stable. In addition to providing the structural framework for designing novel IL-5 agonists and antagonists, the knowledge gained from the development of mono5 will enable other helical bundle proteins to be redesigned with therapeutic potential.Abbreviations ELISA Enzyme-linked immunosorbent assay - IFN Interferon - IL Interleukin - mAb Monoclonal antibody - MAPK Mitogen-activated protein kinase     

The consequences of a failed femoropopliteal bypass grafting: comparison of saphenous vein and PTFE grafts

OBJECTIVES: Although there are numerous reports comparing saphenous vein (SV) and polytetrafluoroethylene (PTFE) with respect to the patency rates for femoropopliteal bypass grafts, the clinical consequences of failed grafts are not as well described. This study compares the outcomes of failed SV and PTFE grafts with a specific emphasis on the degree of acute limb ischemia caused by graft occlusion. METHODS: Over a 6-year period, 718 infrainguinal revascularization procedures were performed, of which 189 were femoropopliteal bypass grafts (SV, 108; PTFE, 81). Society for Vascular Surgery/International Society for Cardiovascular Surgery (SVS/ISCVS) standardized runoff scores were calculated from preoperative arteriograms. Clinical categories of acute limb ischemia resulting from graft occlusion were graded according to SVS/ISCVS standards (I, viable; II, threatened; III, irreversible). Primary graft patency and limb salvage rates at 48 months were calculated according to the Kaplan-Meier method. RESULTS: Patients were well matched for age, sex, and comorbidities. Chronic critical ischemia was the operative indication in most cases (SV, 82%; PTFE, 80%; P =.85). Runoff scores and preoperative ankle-brachial index measurements were similar for the two groups (SV, 6.0 +/- 2.5 [SD] and 0.51 +/- 0.29; PTFE, 5.3 +/- 2.8 and 0.45 +/- 0.20; P =.06 and P =.12). The distal anastomosis was made below the knee in 60% of SV grafts and 16% of PTFE grafts (P <.001). Grade II ischemia was more likely to occur after occlusion of PTFE grafts (78%) than after occlusion of SV grafts (21%; P =.001). Emergency revascularization after graft occlusion was required for 28% of PTFE failures but only 3% of SV graft failures (P <.001). Primary graft patency at 48 months was 58% for SV grafts and 32% for PTFE grafts (P =.008). Limb salvage was achieved in 81% of SV grafts but only 56% of PTFE grafts (P =.019). CONCLUSIONS: Patients undergoing femoropopliteal bypass grafting with PTFE are at greater risk of ischemic complications from graft occlusion and more frequently require emergency limb revascularization as a result of graft occlusion than patients receiving SV grafts. Graft patency and limb salvage are superior with SV in comparison with PTFE in patients undergoing femoropopliteal bypass grafting.