Attitudes towards genetic testing: analysis of contradictions

A survey study was conducted among 1169 people to evaluate attitudes towards genetic testing in Finland. Here we present an analysis of the contradictions detected in people's attitudes towards genetic testing. This analysis focuses on the approval of genetic testing as an individual choice and on the confidence in control of the process of genetic testing and its implications. Our analysis indicated that some of the respondents have contradictory attitudes towards genetic testing. It is proposed that contradictory attitudes towards genetic testing should be given greater significance both in scientific studies on attitudes towards genetic testing as well as in the health care context, e.g. in genetic counselling.     

Correct utilization of exercise electrocardiographic leads in differentiation of men with coronary artery disease from patients with a low likelihood of coronary artery disease using peak exercise ST-segment depression

In this study we compared the diagnostic characteristics of the individual exercise electrocardiographic leads, 3 different lead sets comprising standard leads and the effect of the partition value in the detection of coronary artery disease (CAD). The diagnostic variable used was ST-segment depression at peak exercise, and the study population consisted of 101 patients with CAD and 100 patients with a low likelihood of the disease. The lead system used was the Mason-Likar modification of the standard 12-lead system and exercise tests were performed on a bicycle ergometer. The comparisons were performed by means of receiver-operating characteristic analysis and by determining sensitivities at a fixed 95% specificity. These properties, defined here as diagnostic capacity, were the most efficacious in leads I, -aVR, V4, V5, and V6. Diagnostic capacities in leads aVL, aVF, III, V1, and V2 were quite poor; statistical comparisons indicated significant differences between these leads and lead V5 (p < or = 0.0001 in each case). Use of the maximum value of ST-segment depression at peak exercise derived from all 12 leads produced a considerable decrease in the diagnostic capacity of the exercise electrocardiogram compared with lead V5. The exclusion of leads aVL, V1, and III improved the diagnostic capacity compared with the 12-lead set, but it was still smaller than that of lead V5. With use of a lead set with the 5 best leads increased the diagnostic capacity over other lead sets and over any individual lead. Further improvement was noted when a 50% smaller partition value was applied to leads I and -aVR than for the other leads (p = 0.041). In conclusion, this study suggests that use of leads I, -aVR, V4, V5, and V6 is the most influential when differentiating between patients with CAD and patients with a low likelihood of disease using peak exercise ST-segment depression. The effective use of leads I and -aVR requires the partition value applied for these leads to be 50% smaller than that used for the lateral precordial leads.     

Improved SERS Intensity from Silver‐Coated Black Silicon by Tuning Surface Plasmons

An economical method of fabricating large‐area (up to a 100‐mm wafer) silver (Ag)‐coated black silicon (BS) substrates is demonstrated by cryogenic deep reactive ion etching with inductively coupled plasma. This method enables a simple adjustment of the spike structure (e.g., height, width, sidewall slope and density of the spikes) on the silicon substrate, which thus offers the advantages of accurate tuning the density and amplitude of the localized surface plasmons after Ag coating. Using this method, an enhancement factor of 10⁹ is achieved for the probe molecule of rhodamine 6G (around two orders of magnitude higher than previous results based on Ag‐coated BS) in surface‐enhanced Raman scattering (SERS) measurement. The presented results pave the way to make Ag‐coated BS substrates as economic and large‐area platforms for diverse surface plasmon related applications (such as SERS and surface plasmon based biosensors).     

Degradative and mechanical properties of a novel resorbable plating system during a 3-year follow-up in vivo and in vitro

We tested the tissue reactions and mechanical strength of a novel biodegradable craniomaxillofacial plating system, Inion CPS™, in the course of degradation. Plates and screws composed of l-lactide, d-lactide and trimethylene carbonate were implanted to the mandible and dorsal subcutis of 12 sheep. The animals were sacrificed at 6–156 weeks. Histological evaluation was done using paraffin and methylmetacrylate techniques. Degradative and mechanical properties during the follow-up were measured both of in vivo and in vitro implants. In light microscopy, the in vivo implant material began to fragment at 52 weeks and could not be detected at 104 weeks. No significant foreign body reactions were seen in the mandibles. The dorsal subcutis disclosed mild reactions, which were, however, not of clinical significance. The implants in vitro maintained their entire mass for 26 weeks and lost 63–80% of the mass by week 104. The inherent viscosity of the implants in vitro and in vivo diminished uniformly. The screws retained their shear strength for 12–16 weeks. The plates maintained their tensile strength for at least 6 weeks. The maximum capacity of the plates in 3-point bending tests diminished gradually by 87% in 26 weeks. In conclusion, the plates and screws examined maintain adequate strength for the healing period of a bone fracture or osteotomy, producing no harmful foreign body reactions. Dr Nieminen is a consultant for Inion Ltd., while the other co-authors do not have any conflicts of interest. Inion Ltd. has financed the costs related to the study sheep, including their housing.     

Alkaline Partial Wet Oxidation of Lignin for the Production of Carboxylic Acids

The production of carboxylic acids by partial wet oxidation of alkali lignin was studied experimentally. The factors influencing the different types of products, their yields and concentrations were investigated. Formic, acetic, succinic, oxalic, and glutaconic acid were the main identified products. Both the temperature and oxygen partial pressure are shown to have direct effects on the product yields whereas the lignin concentration has an indirect effect. At low lignin concentrations, the yield of products was relatively high. However, at higher concentrations, the yield decreased. By measuring the lignin molecular weight distributions, it is shown that this decrease is linked to repolymerization/condensation reactions of lignin fragments which compete with oxidative lignin depolymerization.     

Utilization of Pisat temperature-dependency in modelling adsorption on zeolites

In this study, the feasibility of utilizing pure component saturated vapour pressure P_i^sat in representing the temperature-dependency of physisorption of vapours on zeolites is examined. Adsorption data of water, alcohols and aromatic compounds both on hydrophilic on and hydrophobic zeolites has been collected from the literature and represented as a function of P/P_i^sat. It is found that the temperature-dependency of adsorption of a component can be described by the saturated vapour pressure, especially for water adsorption on zeolites. For systems where chemisorption also plays an important role, such as aromatics adsorption on zeolites, P_i^sat alone is not capable of predicting the temperature-dependency accurately enough. It is also observed that contrary to common practice, the maximum adsorption loading q_i^sat on zeolite should be considered independent of temperature. The proposed approach can be used in the modelling and design of industrial processes exploiting adsorption, such as in zeolite membrane systems, where separation is based on both adsorption and diffusion phenomena.     

The long-term performance of Co/SiO2 catalysts in CO hydrogenation

The activity in terms of conversion of carbon monoxide was determined for Co/SiO₂ catalysts in CO hydrogenation over a reaction time of 120 h. The catalysts were prepared from nitrate (N) and carbonyl (CO) precursors. The conversion decreased rapidly during the first five hours, and thereafter moderately at a rate related to dispersion, i.e. the higher the dispersion the higher the rate of decrease. The active sites were blocked by wax and coke formed in the reaction, although some agglomeration of particles probably took place on the Co(CO)/SiO₂ catalysts. More carbon was accumulated on Co(CO)/SiO₂ than on Co(N)/SiO₂ during the reaction suggesting a need for frequent regeneration. The reduction-oxidation-reduction treatments indicated, however, that the regenerability of the Co(CO)/SiO₂ in terms of hydrogen uptake is poor, although the amounts adsorbed still remained higher than those for Co(N)/SiO₂.     

Preparation and characterization of Co/SiO2, Co-Mg/SiO2 and Mg-Co/SiO2 catalysts and their activity in CO hydrogenation

Co/SiO₂, Mg-Co/SiO₂ and Co-Mg/SiO2 catalysts were prepared from acetate, nitrate or carbonyl precursors. The catalysts were characterized by XRD, XPS, SIMS and TGA. The steady-state activity and product distribution of the catalysts were evaluated in synthesis gas reactions at 0.5 MPa and 235-290°C using 3 : 1 : 3 molar ratio of Ar : CO : H₂. The activity in CO hydrogenation decreased in the precursor order Co₂(CO)₈>Co(NO₃)₂> Co(CH₃COO)₂, and the probability of chain growth decreased in the precursor order Co(NO₃)₂>Co₂(CO)₈>Co(CH₃COO)₂. Alcohol yields were highest with Co₂(CO)₈, and lowest with Co(NO₃)₂, Magnesium promotion influenced the catalyst activity and decreased the CO₂ formation, but the promotion effects were less profound than those of the precursor. Surface studies on partially magnesium covered cobalt foil model catalysts suggested that magnesium promotes CO dissociation and chain growth, neither of which were, however, observed in the supported catalysts.