Flight deck magnetic fields in commercial aircraft

BACKGROUND: Airline pilots are exposed to magnetic fields generated by the aircraft's electrical system. The objectives of this study were (1) to directly measure flight deck magnetic fields in terms of personal exposure to the pilots when flying on different aircraft types over a 75-hour flight-duty month, and (2) to compare magnetic field exposures across flight deck types and job titles. METHODS: Measurements were taken using personal dosimeters carried by either the Captain or the First Officer on Boeing 737/200, Boeing 747/400, Boeing 767/300ER, and Airbus 320 aircraft. RESULTS: Approximately 1,008 block hours were recorded at a sampling frequency of 3 seconds. Total block time exposure to the pilots ranged from a harmonic geometric mean of 6.7 milliGauss (mG) for the Boeing 767/300ER to 12.7 mG for the Boeing 737/200. CONCLUSIONS: Measured flight deck magnetic field levels were substantially above the 0.8-1 mG level typically found in the home or office and suggest the need for further study to evaluate potential health effects of long-term exposure.     

Prediction of nuclear maturity from cumulus-coronal morphology: Influence of embryologist experience

Purpose A majority of in vitro fertilization (IVF) programs continues to evaluate oocyte maturity on the basis of cumulus-coronal morphology (CCM) even though marked asynchrony has been reported between CCM and nuclear maturity. This study was designed to examine changes in embryologists' ability to correctly predict nuclear maturity from CCM as a function of increasing experience. Nuclear maturity was assessed by inverted microscopy with a modified spreading technique at follicular aspiration. A second objective was to determine the percentage of oocytes which displayed asynchrony between CCM and nuclear maturity as assessed by embryologists with extensive experience in oocyte maturity evaluation.Results The three participating embryologists had directly evaluated 1304, 75, and 0 oocytes for nuclear maturity and CCM at study initiation and correctly predicted nuclear maturity from CCM in 74, 64, and 47% of oocytes, respectively. Embryologist 1 did not significantly change in predictive ability during the 17-month study period. Embryologist 2 significantly improved in predictive ability during the first 9 months of the study (841 oocytes evaluated) and plateaued thereafter, at a similar percentage of correct predictions as embryologist 1. Embryologist 3 continued to improve in predictive ability throughout the study period, reaching 61% correct predictions at the close of the study after evaluating 223 oocytes. Once embryologists had plateaued in their predictive ability, 72% of oocytes evaluated received the correct nuclear maturity classification based on CCM. Significantly fewer oocytes (54%; 375/690) evaluated by embryologists who had not plateaued in their predictive ability received the correct nuclear maturity classification based on CCM.Conclusions These results indicate that embryologists' ability to predict oocyte nuclear maturity correctly from CCM continues to change over several months even when pretraining video recordings are used before beginning direct evaluations. After embryologists plateaued in their predictive ability, nuclear maturity still could not be correctly predicted from CCM in 28% of oocytes due to asynchrony between nuclear and CCM maturity. Based upon this, circumstances in which the spreading technique should be used for direct assessment of nuclear maturity as opposed to assessment of CCM only are discussed.     

Multi-centre research surveillance project to reduce infections/phlebitis associated with peripheral vascular catheters

A surveillance project was undertaken on 37 surgical wards by infection control nurses with the aim of reducing phlebitis/infections associated with peripheral vascular catheters, and to identify risk factors. Data on 2934 catheters in situ longer than 24h was collected in two separate surveillance periods and results were fed back after each surveillance period. Four significant risk factors were identified; what the catheters were used for, the duration the catheters were in situ, the surveillance period (the first surveillance period had a higher phlebitis rate than the second) and whether an infusion pump was used. Logistic regression analysis showed that each of these had a significant effect after adjusting for the effects of the other three factors.     

Local cone and rod system function in progressive cone dystrophy

PURPOSE: To compare the patterns of local cone and rod system impairment in patients with progressive cone dystrophy (CD) using psychophysical and electrophysiological techniques. METHODS: Local cone system function was assessed by measuring cone system thresholds (visual fields) and cone-mediated multifocal electroretinograms (mfERGs). Rod system function was assessed by measuring rod system thresholds (visual fields) and rod-mediated mfERGs. The results in a group of eight patients with CD were compared with those in an age-similar control group. RESULTS: All the patients had abnormal cone system visual field thresholds and cone-mediated mfERGs. Cone system psychophysical thresholds were elevated for targets presented within the central 10 degrees, but were within normal limits for targets at peripheral locations. Cone-mediated mfERG measures of amplitude scale and time scale were abnormal for most of the hexagons tested. Most of the rod-mediated psychophysical thresholds and mfERGs were within normal limits. Rod system losses tended to be patchy and scattered throughout the area tested. CONCLUSIONS: There was poor correspondence among local measures of cone and rod system losses in these patients with CD. The results suggest that the spatial pattern of cone system losses in this disease differs from the spatial pattern of rod system losses.     

The effects of visuomotor feedback training on the recovery of hemispatial neglect symptoms: assessment of a 2-week and follow-up intervention

In patients suffering from left unilateral neglect, their right-biased attention to the phenomenal world can be ameliorated, short-term, by making motor responses to left-right extended objects (rods) that immediately reveal to them that their phenomenal world is in fact skewed. In this study the extent to which more intensive experiences of this type produced enduring and useful improvements in neglect, was assessed by first examining the effect of a 3-day experimenter-administered practice of rod lifting, then by examining the effects of a self-administered practice for a further 2-week period and a further 1 month post-training. Despite the fact that by the time the patients were able to undergo the intervention they had progressed to the chronic neglect stage, significant improvements of the intervention over the control group were found for a third of the tests given after the 3-day practice. Additionally, at the 1-month follow-up the intervention group again showed significantly better results in 46% of the direct neglect tests. As far as we are aware this is the first time that significant long-term improvements have been shown in a rehabilitation approach with neglect patients with a mean time of more than 12 months post-stroke and visuomotor feedback training can thus be seen as a most encouraging paradigm for future attempts.     

Genetic effects on age-dependent onset and islet cell autoantibody markers in type 1 diabetes

Age-dependent associations between type 1 diabetes risk genes HLA, INS VNTR, and CTLA-4 and autoantibodies to GAD65 (GADAs), ICA512/IA-2, insulin, and islet cells were determined by logistic regression analysis in 971 incident patients with type 1 diabetes and 702 control subjects aged 0-34 years. GADAs were associated with HLA-DQ2 in young but not in older patients (P = 0.009). Autoantibodies to insulin were negatively associated with age (P < 0.0001) but positively associated with DQ8 (P = 0.03) and with INS VNTR (P = 0.04), supporting possible immune tolerance induction. ICA512/IA-2 were negatively associated with age (P < 0.0001) and with DQ2 (P < 0.0001) but positively associated with DQ8 (P = 0.04). Males were more likely than females to be negative for GADA (P < 0.0001), autoantibodies to islet cells (P = 0.04), and all four autoantibody markers (P = 0.004). The CTLA-4 3' end microsatellite marker was not associated with any of the autoantibodies. We conclude that age and genetic factors such as HLA-DQ and INS VNTR need to be combined with islet autoantibody markers when evaluating the risk for type 1 diabetes development.     

Three-dimensional phase-contrast magnetic resonance angiography: a useful clinical adjunct to gadolinium-enhanced three-dimensional renal magnetic resonance angiography?

OBJECTIVE: To assess the value of three-dimensional (3D) phase-contrast (PC) magnetic resonance angiography (MRA) after gadolinium (Gd)-enhanced 3D MRA for renal artery imaging. METHODS: Twenty-one patients with suspected renal artery hypertension were reviewed. All studies included Gd-enhanced 3D MRA and 3D PC MRA. Blinded interpretation of the images was performed for each technique independently and in combination. Conventional X-ray angiography was used for diagnostic correlation when available. RESULTS: Renal artery stenosis was present in 7 (16.3%) of 43 renal arteries, confirmed by X-ray angiography. MRA images demonstrated 100% sensitivity and 74% specificity for Gd-enhanced 3D MRA and 100% sensitivity and 94% specificity for 3D PC MRA. All vessels were diagnosed correctly when both image sets were viewed. CONCLUSION: 3D PC MRA can improve the specificity of renal MRA by decreasing the number of false-positive Gd-enhanced 3D MRA interpretations.     

Peloruside A,a novel antimitotic agent with paclitaxel-like microtubule- stabilizing activity

Peloruside A is a novel secondary metabolite isolated from a New Zealand marine sponge, Mycale hentscheli, that has potent paclitaxel-like microtubule-stabilizing activity and is cytotoxic at nanomolar concentrations. Its 16-membered macrolide ring is similar to that of epothilone, a drug currently under clinical investigation as an anticancer agent. Like paclitaxel, peloruside A arrests cells in the G(2)-M phase of the cell cycle and induces apoptosis. The relatively simple structure of peloruside makes it suitable for the design and synthesis of analogues with improved tumor targeting and reduced tumor cross-resistance.     

Insulin-like growth factor binding proteins 1 and 3 and breast cancer outcomes

The IGF family of growth factors is believed to play a role in the development and progression of breast cancer. We recently identified an adverse prognostic effect of insulin in breast cancer; we now report prognostic effects of circulating IGFBP's 1 and 3. 512 women with T1-3, N0-1, M0 breast cancer provided fasting blood which was analysed for IGFBP's 1 and 3. Information on body size, diet and traditional prognostic factors and treatment was obtained; women were followed for recurrence and death. IGFBP-1 levels correlated inversely with insulin levels (Spearman r = –0.60, p < 0.0001), reflecting known inhibition of IGFBP-1 gene expression by insulin. Insulin explained 36% of the variance in IGFBP-1 levels. IGFBP-1 levels were also correlated with obesity and diet. Levels of IGFBP-1 significantly predicted distant recurrence and death, hazard ratio (95% CI) for lower versus upper quartile 2.08 (1.20–3.61) and 3.0 (1.45–6.21), respectively. These effects persisted after adjustment for tumor-related variables and treatment but were not independent of insulin levels. High levels of IGFBP-3 predicted distant recurrence (hazard ratio upper v.s. lower quartile 1.8, 95% CI 1.1–3.0) but not death (hazard ratio 1.0, 95% CI 0.5–1.9). The effect on distant recurrence was restricted to postmenopausal women (hazard ratio 3.8, 95% CI 1.6–9.0) and to those with estrogen receptor positive tumors (p = 0.002). Prognostic effects of IGFBP-1 appear related to the known effect of insulin on IGFBP-1 gene expression. The adverse effect of IGFBP-3 on distant recurrence in postmenopausal women with estrogen receptor positive breast cancer should be further investigated.