Characteristics of effective Internet-mediated interventions to change lifestyle in people aged 50 and older: a systematic review.

Worldwide, the number of people aged 60 years and older steadily grows to a predicted 2 billion in 2050. Online interventions increasingly target lifestyle risk factors to promote healthy aging. The objective of this systematic review is to evaluate whether Internet mediated lifestyle interventions can successfully change lifestyle in people aged 50 and older. A PubMed search was conducted resulting in twelve articles, based on ten studies. The studies focused on physical activity, weight loss, nutrition, and diabetes. Nine studies used feasible interventions, with an average small to moderate effect size. The most important result is that there are multiple studies reporting positive lifestyle changes in an older population. On average, complex interventions, whether they present tailored or generic information, and online or offline comparison, are more effective than interventions with only one component. Internet mediated interventions hold great potential in implementing effective lifestyle programs, capable of reaching large populations of older persons at very low costs.

Determination of the accuracy of implant reconstruction and dose delivery in brachytherapy in The Netherlands and Belgium.

PURPOSE: To gain insight into the accuracy of brachytherapy treatments, the accuracy of implant reconstruction and dose delivery was investigated in 33 radiotherapy institutions in The Netherlands and Belgium. MATERIALS AND METHODS: The accuracy of the implant reconstruction method was determined using a cubic phantom containing 25 spheres at well-known positions. Reconstruction measurements were obtained on 41 brachytherapy localizers, 33 of which were simulators. The reconstructed distances between the spheres were compared with the true distances. The accuracy of the dose delivery was determined for high dose rate (HDR), pulsed dose rate (PDR) and low dose rate (LDR) afterloading systems using a polymethyl methacrylate cylindrical phantom containing a NE 2571 ionization chamber in its centre. The institutions were asked to deliver a prescribed dose at the centre of the phantom. The measured dose was compared with the prescribed dose. RESULTS: The average reconstruction accuracy was -0.07 mm (+/-0.4 mm, 1 SD) for 41 localizers. The average deviation of the measured dose from the prescribed dose was +0.9% (+/-1.3%, 1 SD) for 21 HDR afterloading systems, +1.0% (+/-2.3%, 1 SD) for 12 PDR afterloaders, and +1.8% (+/-2.5%, 1 SD) for 15 LDR afterloaders. CONCLUSIONS: This comparison showed a good accuracy of brachytherapy implant reconstruction and dose delivery in The Netherlands and Belgium.

Urinary metabolite profile of phenyl and o-cresyl glycidyl ether in rats: identification of a novel pathway leading to N-acetylserine O-conjugates.

The urinary excretion of metabolites of phenyl glycidyl ether (PGE) and o-cresyl glycidyl ether (o-CGE) was investigated in rats. Urine was collected, in fractions, from rats intraperitoneally administered PGE or o-CGE in doses ranging from 0.033 to 1.0 mmol/kg. The metabolites were extracted from acidified urine with ethyl acetate or diethyl ether, and their identity was elucidated by GC/MS analysis. The epoxide of PGE can be inactivated by glutathione (GSH) conjugation or epoxide hydrolysis. After further metabolism, these routes lead to the urinary excretion of phenyl glycidyl ether mercapturic acid (PGEMA) and 3-(phenyloxy)lactic acid (POLA). The excretion of PGEMA and POLA was described before and is confirmed in this study. Additionally, a new metabolite was identified as N-acetyl-O-phenylserine (NAPS), which is proposed to be formed from POLA by subsequent oxidation, transamination, and N-acetylation. For PGEMA a linear dose-excretion relationship was found (r2 = 0.988), and the percentage of the dose excreted declined from 27% to 10% with increasing PGE dose. For NAPS also a linear dose-excretion relationship was found (r2 = 0.985), and NAPS accounted for 27% of the PGE dose. The excretion of PGEMA and NAPS was rather fast: 93% and 75%, respectively, of the respective total cumulative amounts excreted was already collected within 6 h after administration. The urinary metabolite profile of o-CGE was not investigated in rats before. Three urinary metabolites of o-CGE were identified, namely, 3-(o-cresyloxy)lactic acid (COLA), o-cresyl glycidyl ether mercapturic acid (o-CGEMA), and N-acetyl-O-(o-cresyl)serine (NACS), showing that the metabolite profiles of PGE and o-CGE are comparable. Up to a o-CGE dose of 0.333 mmol/kg, the excretion of o-CGEMA was linear (r2 = 0.997), while above this dose the excretion did not increase anymore. The percentage of the o-CGE dose excreted as o-CGEMA declined from 31% to 11% with increasing dose. Again 93% of the total cumulative amount of o-CGEMA excreted was collected within 6 h after administration of o-CGE. Analytical methods were developed for the quantitative determination of mercapturic acid metabolites of PGE and o-CGE. These methods were sufficiently sensitive for their determination in urine of rats administered PGE or o-CGE in the dose range applied. It is anticipated that the analytical methods developed are also sufficiently sensitive to investigate excretion of the mercapturic acid metabolites in humans occupationally exposed to low air concentrations (<6 mg/m3 of air, 8h-TWA) of PGE or o-CGE.

Plastics from household waste as a source of heavy metal pollution. An inventory study using INAA as the analytical technique.

An inventory study to the levels of cadmium in the plastic component of household waste was carried out utilizing INAA as the analytical technique. In a 2-h irradiation, 2-d decay, and 1-h measurement, protocol adequate sensitivities could be obtained for Cd, but also for a group of other metals: Cr, Co, Ni, Cu, Sr, Zn, As, Se, Mo, Sn, Sb, Ba, and Hg. Red-, orange-, and yellow-colored plastics either contain Cd at high levels (over 1000 mg/kg) or have relatively low Cd concentrations (less than 50 mg/kg). High concentrations were also occasionally found for Sr, Se, Ba, Sb, and Hg. INAA appeared very well to be routinely usable for such analysis because of the absence of a destruction step, adequate sensitivity, high accuracy, and multielement results.

Trace-element concentrations in human autopsy tissue.

In this report on trace-element concentrations (As, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Zn) in human heart, liver, kidney, aorta, and rib obtained from 200 autopsied patients, we give special attention to sampling procedure, analysis technique, and various sources of error (autolysis, contamination with blood, and lack of sample homogeneity). We present the concentration data (averages, standard deviations, and ranges) obtained by neutron activation analysis, and we analyze the distribution of the data. The three types of distribution we distinguished are relevant to considerations of the importance of processes of storage of certain elements in specific organs.

Relationships between trace elements and atherosclerosis.

The possible relationship between trace element (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Zn) concentrations in various human tissues (heart, liver, kidney, aorta, rib and head hair) and cardiovascular diseases was studied on the basis of indications in the literature that trace elements may be directly or indirectly involved in cardiovascular disease processes. The underlying theme was that (slightly) reduced, as well as (slightly) elevated, concentrations compared with optimum values could, in the long term, lead to atherosclerotic lesions. In this project the tissues were obtained by autopsy involving 200 individuals (hospitalised patients and victims of traffic accidents). The seriousness of cardiovascular disease was quantitatively expressed by the degree of atherosclerosis of the descending branch of the left coronary artery (LAD) and of the abdominal aorta, for which a special measurement method was developed. Correlations were evaluated by two different methods, i.e. by a comparison of patients with extremely high or extremely low degrees of atherosclerosis and by means of stepwise multiple linear regression (SMLR) analysis. Corrections were made for the influence of age. The element Cd was found to be positively, and the elements Cu, Co, Se and Zn negatively, correlated with the degree of atherosclerosis. The inclusion of risk factors (diabetes mellitus, hypercholesterolaemia, hypertension, obesity and smoking) did not improve the explained variance.