Protection of the environment from ionising radiation in a regulatory context--an overview of the PROTECT coordinated action project

The outcome of the PROTECT project (Protection of the Environment from Ionising Radiation in a Regulatory Context) is summarised, focusing on the protection goal and derivation of dose rates which may detrimentally affect wildlife populations. To carry out an impact assessment for radioactive substances, the estimated dose rates produced by assessment tools need to be compared with some form of criteria to judge the level of risk. To do this, appropriate protection goals need to be defined and associated predefined dose rate values, or benchmarks, derived and agreed upon. Previous approaches used to estimate dose rates at which there may be observable changes in populations or individuals are described and discussed, as are more recent derivations of screening benchmarks for use in regulatory frameworks. We have adopted guidance and procedures used for assessment and regulation of other chemical stressors to derive benchmarks. On the basis of consultation with many relevant experts, PROTECT has derived a benchmark screening dose rate, using data on largely reproductive effects to derive species sensitivity distributions, of 10 microGy h(-1) which can be used to identify situations which are below regulatory concern with a high degree of confidence.

A multi-criteria weight of evidence approach for deriving ecological benchmarks for radioactive substances

Dose rate benchmarks are required in the tiered approaches used to screen out benign exposure scenarios in radiological ecological risk assessment. Such screening benchmarks, namely the predicted no-effect dose rates (PNEDR), have been derived by applying, as far as possible, the European guidance developed for chemicals. To derive the ecosystem level (or generic) PNEDR, radiotoxicity EDR(10) data (dose rates giving a 10% effect in comparison with the control) were used to fit a species sensitivity distribution (SSD) and estimate the HDR(5) (the hazardous dose rate affecting 5% of species with a 10% effect). Then, a multi-criteria approach was developed to justify using an assessment factor (AF) to apply to the HDR(5) for estimating a PNEDR value. Several different statistical data treatments were considered which all gave reasonably similar results. The suggested generic screening value of 10 microGy h(-1) (incremental dose rate) was derived using the lowest available EDR(10) value per species, an unweighted SSD, and an AF of 2 applied to the estimated HDR(5). Consideration was also given to deriving screening benchmark values for organism groups but this was not thought to be currently appropriate due to few relevant data being currently available.

Dynamical stabilization of the body centered cubic phase in lanthanum and thorium by phonon-phonon interaction

A recently developed self-consistent ab initio lattice dynamical method has been applied to the high temperature body centered cubic (bcc) phase of La and Th, which are dynamically unstable at low temperatures. The bcc phase of these metals is found to be stabilized by phonon-phonon interactions. The calculated high temperature phonon frequencies for La are found to be in good agreement with the corresponding experimental data.

The Q-T syndrome--a family description

This paper describes a family of nine siblings of whom five suffer from the surdocardiac syndrome. All five are deaf-mute and have medical histories typical of the syndrome, with frequent syncopal attacks during the childhood, often caused by stress. Two of these five siblings have not suffered more than single attacks since puberty and are still alive. The other three had had continuous frequent attacks into adult years and died in connection with syncopes at 20, 27 and 37 years of age. The diagnosis, pathogenesis, treatment and genetics of the syndrome are discussed.

Role of surgery in infective endocarditis

One-hundred-and-thirteen patients with endocarditis and valvular insufficiency were studied retrospectively with special regard to indications for operation and the optimum time for cardiac valve surgery. Thirty patients (group I) had acute, 63 (group II) subacute and 20 (group III) prosthetic valve endocarditis. Group I: Eleven patients underwent surgery in the acute stage, 8 while bacteremic; 5 of the latter died perioperatively. Of the 19 patients treated medically, 16 died. Group II: All patients underwent operation in a bacteria-free state. The mortality was 5%. Group III: Eight patients had early (less than 60 days postoperatively) and 12 late endocarditis. Total mortality was 40% (71% early and 25% late mortality). Ten patients underwent reoperation, with a mortality of 20%, compared with 60% in the medically treated group. The results support the indication for early operation in acute endocarditis with progressive cardiac failure and renal failure and prosthetic valve endocarditis, even during bacteremia.

Comparison of oral health assessments between nursing staff and patients on medical wards

The maintenance of good oral health is essential for nutrition, recovery and well-being. This requires the involvement of the nursing staff, especially in cases where oral care and any necessary dental treatment are vital to ensure medical treatment. The aim of this study was to evaluate the validity of oral assessments performed by nursing staff using the revised oral assessment guide (ROAG), using comparisons with patients' self-assessment of oral problems. When a comparison was made of how the staff and patients assessed their oral status, a high level of agreement was found. In these assessments, with the exception of oral mucosa and teeth, the percentage agreement was >80. The kappa coefficient revealed slight to moderate agreement. When there was a disagreement, the staff assessed the oral health as being significantly poorer than the patients did. In the present study, it was shown that few oral assessments performed by the nursing staff and patient disagreed. The ROAG may therefore be useful for the nursing staff to make the patients' oral health problems visible.

Automatic fitting procedures for EPR spectra of disordered systems: matrix diagonalization and perturbation methods applied to fluorocarbon radicals

Two types of automatic fitting procedures for EPR spectra of disordered systems have been developed, one based on matrix diagonalization of a general spin Hamiltonian, the other on 2nd order perturbation theory. The first program is based on a previous Fortran code complemented with a newly written interface in Java to provide user-friendly in and output. The second is intended for the special case of free radicals with several relatively weakly interacting nuclei, in which case the general method becomes slow. A least squares' fitting procedure utilizing analytical or numerical derivatives of the theoretically calculated spectrum with respect to the g- and hyperfine structure (hfs) tensors was used to refine those parameters in both cases. 'Rigid limit' ESR spectra from radicals in organic matrices and in polymers, previously studied experimentally at low temperature, were analyzed by both methods. Fluorocarbon anion radicals could be simulated, quite accurately with the exact method, whereas automatic fitting on, e.g. the c-C(4)F(8)(-) anion radical is only feasible with the 2nd order approximative treatment. Initial values for the (19)F hfs tensors estimated by DFT calculations were quite close to the final. For neutral radicals of the type XCF(2)CF(2)* the refinement of the hfs tensors by the exact method worked better than the approximate. The reasons are discussed. The ability of the fitting procedures to recover the correct magnetic parameters of disordered systems was investigated by fittings to synthetic spectra with known hfs tensors. The exact and the approximate methods are concluded to be complementary, one being general, but limited to relatively small systems, the other being a special treatment, suited for S=1/2 systems with several moderately large hfs.

Polymorphisms in cytokine genes influence long-term survival differently in elderly male and female patients

OBJECTIVES

We asked if single nucleotide polymorphisms (SNP) in inflammatory cytokine genes related to 3-year survival in ill elderly subjects and if genotypes differed between the elderly and a younger control population.

DESIGN

Prospective observational study.

SETTING

Two geriatric departments at a university hospital.

SUBJECTS

Eighty three acutely admitted geriatric patients (83 +/- 7 year, 70% women) and 207 young healthy subjects (40 +/- 1 year, 37% women) were included.

OUTCOME MEASURES

Single nucleotide polymorphisms in the genes of tumour necrosis factor (TNF)-alpha-308 G/A, interleukin (IL)-1beta-511 C/T, IL-6-174 G/C and IL-10-1082 A/G were analysed. In the geriatric patients SNP in lymphotoxin (LT)-alpha +252 G/A and serum levels of TNF-alpha, IL-6, IL-10, soluble IL-I receptor(R)II were also determined, as well as the 3-year mortality.

RESULTS

The allele distribution did not differ significantly between the elderly and the young. In the female elderly, 3-year survival was doubled (P < 0.05) in those with the high-producing genotypes of IL-6 -174 GG and TNF-alpha -308 GA compared with those with low-producing alleles. In contrast, men with high-producing LT-alpha +252 AA and IL-1beta-511 CT&TT genotypes displayed halved 3-year survival (P < 0.05) compared with those with low-producing genotypes, whereas possession of the high-producing IL-10 -1082 GG genotype favoured survival. Serum IL-10 was higher in the high-producing IL-10 genotype in females.

CONCLUSION

As high-producing IL-6 -174 genotype favoured 3-year survival in women, whereas the likewise high-producing LT-alpha +252 and IL-1beta -511 genotypes were associated with poor survival in men, we conclude that the specific genotypes, in association with gender, may act as determinants for survival in elderly patients.

Impact of post-synaptic block of neuromuscular transmission, muscle unloading and mechanical ventilation on skeletal muscle protein and mRNA expression

To analyse mechanisms of muscle wasting in intensive care unit patients, we developed an experimental model where rats were pharmacologically paralysed by post-synaptic block of neuromuscular transmission (NMB) and mechanically ventilated for 9+/-2 days. Specific interest was focused on the effects on protein and mRNA expression of sarcomeric proteins, i.e., myosin heavy chain (MyHC), actin, myosin-binding protein C (MyBP-C) and myosin-binding protein H (MyBP-H) in fast- and slow-twitch limb, respiratory and masticatory muscles. Muscle-specific differences were observed in response to NMB at both the protein and mRNA levels. At the protein level, a decreased MyHC-to-actin ratio was observed in all muscles excluding the diaphragm, whereas at the mRNA level a decreased expression of the dominating MyHC isoform(s) was observed in the hind limb and intercostal muscles, but not in the diaphragm and masseter muscles. MyBP-C mRNA expression was decreased in the limb muscles, but it otherwise remained unaffected. MyBP-H conversely increased in all muscles. Furthermore, we found myofibrillar protein and mRNA expression to be affected differently when comparing NMB animals with peripherally denervated (DEN) ambulatory rats. We report that NMB has both a larger and different impact on muscle, at the protein and mRNA levels, than DEN has.

High-level visual-spatial ability for novices correlates with performance in a visual-spatial complex surgical simulator task

BACKGROUND

This study addresses how high-level visual-spatial ability of surgical novices is related to performance of two simulator tasks with (KSA) and without (MIST) anatomic graphics and haptic feedback, differing in visual-spatial complexity.

METHODS

Visual-spatial test scores assessed by Mental Rotation Test (MRT) and BasIQ and performance scores for Instrument Navigation (IN) in Key Surgical Activities (Procedicus KSA) and Manipulate and Diathermy (MD) in Minimally Invasive Surgical Trainer (Procedicus MIST) were correlated for 54 Swedish surgical novices.

RESULTS

Significant Pearson's r correlations were obtained between visual-spatial scores measured by MRT-C and total score from the last trial for IN (r = 0.278, p < 0.05). Visual-spatial scores (measured by BasIQ) also correlated with total score from the first trial (r = 0.443, p < 0.05) and from the last trial (r = 0.489, p < 0.05).

CONCLUSION

High-level visual-spatial ability is important for surgical novices to possess in the early training phase of a visual-spatial complex task in KSA.

Oral health status in individuals with dementia living in special facilities

AIM

The aim of this review was to retrieve data describing the oral health status of individuals with dementia living in special facilities.

MATERIALS AND METHODS

A literature search on the MEDLINE database (Entrez PubMed) was performed. The literature search yielded 208 papers, of which seven publications were selected for evaluation.

RESULTS

From the available studies poorer oral hygiene, decreased saliva flow rates and a higher caries incidence were reported in individuals with dementia living in special facilities when compared with healthy individuals. Oral health problems were more pronounced in the severe stage of the disease.

CONCLUSIONS

There is limited scientific data describing the oral health status of individuals with dementia living in special facilities. However, available data indicate that individuals with dementia living in special facilities have more oral health problems than individuals without dementia.

Factors behind change in knowledge after a mass media campaign targeting periodontitis

The aim of this study was to investigate changes in knowledge before and after a mass media campaign, in relation to social attributes, care system attributes and oral health aspects. The study was based on a questionnaire in a cohort design, sent out to 900 randomly sampled people aged 50-75 in Sweden. The response rate to the questionnaire before and after the campaign was 70% and 65% respectively. Sixty-four percent answered both questionnaires. Two questions addressed knowledge, while 10 questions aimed to measure social attributes, care system attributes and oral health aspects. Data were analysed for bivariate relations as to change in knowledge and social attributes, care system attributes and oral health aspects. Data were also analysed in multiple regression analysis with knowledge before, knowledge after and knowledge differences as dependent variables. The results showed that there were a number of independent variables with influence on the dependent variables. Of the social attributes, secondary education gave almost 10% (P < 0.001) better knowledge both before and after the campaign. Among care system attributes, high care utilization was related to knowledge both before and after the campaign. The most important factors for knowledge about periodontitis were education, care utilization and perceived importance of oral health. In conclusion, this study demonstrates that mass media might increase knowledge about periodontitis as a health promotion strategy.

Observations of the PCB distribution within and in-between ice, snow, ice-rafted debris, ice-interstitial water, and seawater in the Barents Sea marginal ice zone and the North Pole area

To evaluate the two hypotheses of locally elevated exposure of persistent organic pollutants (POPs) in ice-associated microenvironments and ice as a key carrier for long-range transport of POPs to the Arctic marginal ice zone (MIZ), dissolved and particulate polychlorinated biphenyls (PCBs) were analyzed in ice, snow, ice-interstitial water (IIW), seawater in the melt layer underlying the ice, and in ice-rafted sediment (IRS) from the Barents Sea MIZ to the high Arctic in the summer of 2001. Ultra-clean sampling equipment and protocols were specially developed for this expedition, including construction of a permanent clean room facility and a stainless steel seawater intake system on the I/B ODEN as well as two mobile 370 l ice-melting systems. Similar concentrations were found in several ice-associated compartments. For instance, the concentration of one of the most abundant congeners, PCB 52, was typically on the order of 0.1-0.3 pg l(-1) in the dissolved (melted) phase of the ice, snow, IIW, and underlying seawater while its particulate organic-carbon (POC) normalized concentrations were around 1-3 ng gPOC(-1) in the ice, snow, IIW, and IRS. The solid-water distribution of PCBs in ice was well correlated with and predictable from K(ow) (ice log K(oc)-log K(ow) regressions: p<0.05, r2=0.78-0.98, n=9), indicating near-equilibrium partitioning of PCBs within each local ice system. These results do generally not evidence the existence of physical microenvironments with locally elevated POP exposures. However, there were some indications that the ice-associated system had harbored local environments with higher exposure levels earlier/before the melting/vegetative season, as a few samples had PCB concentrations elevated by factors of 5-10 relative to the typical values, and the elevated levels were predominantly found at the station where melting had putatively progressed the least. The very low PCB concentrations and absence of any significant concentration gradients, both in-between different matrices and over the Eurasian Arctic basin scale, suggest that ice is not an important long-range transport purveyor of POPs to the Arctic MIZ ecosystem.

Interactions between lipoxin A4, the stable analogue 16-phenoxy-lipoxin A4 and leukotriene B4 in cytokine generation by human monocytes

Lipoxins display both stimulatory and inhibitory actions with leucocytes that are cell-type dependent. We tested whether lipoxin A4 (LXA4) and its stable synthetic analogue 16-phenoxy-17-18,19,20-tetranor-lipoxin-A4 (16-phe-LXA4) modulated the ability of human blood monocytes (MO) to express mRNA and proteins for interleukin-1beta (IL-1beta), IL-6 and IL-1 receptor antagonist (IL-1Ra) in vitro and compared their actions with lipopolysaccharide (LPS) and leukotriene B4 (LTB4). 16-phe-LXA4, LPS and LTB4, but not LXA4, induced gene expression of IL-1beta in MO. IL-1beta protein synthesis increased by LPS (1500-fold), LTB4 (280-fold) and 16-phe-LXA4 (30-fold). Although the IL-1Ra gene was constitutively activated, mRNA concentration not affected by any of the stimulants, IL-Ra protein synthesis was increased by LPS (with 74%), 16-phe-LXA4 (35%) and LTB4 (20%), but not by LXA4. Each of these stimuli upregulated the IL-6 gene. Increases of IL-6 protein were 3000-fold for LPS, threefold for 16-phe-LXA4, eightfold for LXA(4 and) twofold for LTB4. Prior exposure of MO to 16-phe-LXA4, but not LXA4, reduced LTB4 induced synthesis of IL-1beta with 66%, IL-6 with 20% and IL-1Ra with 29%. Thus, a stable LXA analogue, that resists rapid inactivation by monocytes, displays novel actions in cytokine generation, intimately involved in the regulation of inflammation.

Radiative lifetime of a bound excited state of Te-

We report on the first experimental study of the lifetime of a bound excited state of a negative ion. A new experimental technique was developed and used to measure the radiative lifetime of the 5p(5) (2)P(1/2) level of Te-. The experiment was performed in a magnetic storage ring, where a laser beam was applied along one of the straight sections. In the experiment the population of the excited J=1/2 level was probed each time the Te- ions passed through the laser field. A decay curve was built up by sampling the population of the excited level of the Te- ions as a function of time after injection into the ring. A multiconfiguration Dirac-Hartree-Fock calculation was performed in conjunction with the experiment. The calculation yielded a radiative lifetime of 0.45 s, in excellent agreement with the measured value of 0.42(5) s.

Oral health problems in elderly rehabilitation patients

A combination of poor oral hygiene and dry mouth may be hazardous to the oral health status. However, systematic assessments in order to detect oral health problems are seldom performed in the nursing care of the elderly. The aims of this study were to investigate the occurrence of oral health problems measured using the Revised Oral Assessment Guide (ROAG) and to analyse associations between oral health problems and age, gender, living conditions, cohabitation, reason for admission, number of drugs, and functional and nutritional status. One registered nurse performed oral health assessments using ROAG in 161 newly admitted elderly patients in rehabilitation care. Oral health problems were found in 71% of the patients. Thirty per cent of these patients had between four and eight problems. Low saliva flow and problems related to lips were the most frequent oral health problems. Problems in oral health status were significantly associated with presence of respiratory diseases (problems with gums, lips, alterations on the tongue and mucous membranes), living in special accommodation (low saliva flow, problems with teeth/dentures and alterations on the tongue), being undernourished (alterations on the tongue and low saliva flow) and being a woman (low saliva flow). The highest Odds ratio (OR) was found in problems with gums in relation with prevalence of respiratory diseases (OR 8.9; confidence interval (CI) 2.8-27.8; P < 0.0005). This study indicates the importance of standardised oral health assessments in order to detect oral health problems which can otherwise be hidden when the patients are admitted to the hospital ward.