Structural correlates of mild cognitive impairment

The structural correlates of mild cognitive impairment (MCI) were examined in 105 elderly subjects whose cognitive function ranged from intact to demented, including 38 subjects with MCI. Hippocampal volumes (left and right HcV), brain volume (BV), and grey matter volume (GMV) and white matter volume (WMV) were segmented from high resolution magnetic resonance data sets and normalised to intracranial volume (ICV). Hippocampal volume reductions, but not global brain, white or grey matter atrophy, were associated with MCI. White matter lesion severity did not differ over cognitive states. In multiple logistic regression models, normalised HcV and ICV (indicating premorbid brain volume) were significant predictors of MCI versus normality. Normalised BV and ICV significantly predicted dementia versus MCI. Absolute volumetric measures of HcV and BV yielded comparable classification accuracies. Hippocampal atrophy may be the crucial step for the transition from normality to MCI. Widespread brain atrophy may be the step to determine the transition from MCI to dementia. Brain volume reserve effects appear to be involved in both of these steps.     

Two-year study on the effect of professional toothcleaning on schoolchildren in Oppegård, Norway

A longitudinal study on the effect of a preventive program based on bimonthly professional toothcleaning and hygiene instruction was carried out on 293 schoolchildren from the 1st, 4th and 7th grades. The prophylactic paste used contained 0.8%sodium monofluorophosphate. The control groups brushed with a 0.2% sodium fluoride solution four to five times during each school year. After 2 years the Visible Plaque Index and the Gingival Bleeding Index were significantly reduced for all grades in the test groups as compared to the controls. The percentage of children without new caries lesions increased significantly from an average of 50 % in the control to 71% in (he lest group. The mean caries increments during the 2 years, excluding occlusal surfaces, were 0.22, 0.28 and 1.20 in the three test groups. This represents an average caries reduction of 65%, compared to the control group. The increment reductions reached borderline significance, using the chi-square test.     

Über die druckabhängigkeit der viskoelastischen und physikalisch-chemischen eigenschaften von polymeren, 2. Spezifisches volumen und thermische ausdehnung einiger polymeren beim schmelzen und kristallisieren

Measurements of specific volumes are described as function of temperature and pressure of melting or crystallizing linear polyethylene, isotactic polypropylene, and polyoxymethylene. A pressure range of 50 to 1600 bar permits determination of relative volume changes as function of temperature and pressure. Pressure influence on melting points, temperature hysteresis between melting and crystallization and their volume changes as well as the thermodynamic driving force of phase change have been investigated. Clausius-Clapeyron's equation permits calculation of heats of crystallization.     

fMRI Signal Restoration Using a Spatio-Temporal Markov Random Field Preserving Transitions

In fMRI studies, Gaussian filtering is usually applied to improve the detection of activated areas. Such lowpass filtering enhances the signal to noise ratio. However, undesirable secondary effects are a bias on the signal shape and a blurring in the spatial domain. Neighboring activated areas may be merged and the high resolution of the fMRI data compromised. In the temporal domain, activation and deactivation slopes are also blurred. We propose an alternative to Gaussian filtering by restoring the signal using a spatiotemporal Markov Random Field which preserves the shape of the transitions. We define some interaction between neighboring voxels which allows us to reduce the noise while preserving the signal characteristics. An energy function is defined as the sum of the interaction potentials and is minimized using a simulated annealing algorithm. The shape of the hemodynamic response is preserved leading to a better characterization of its properties. We demonstrate the use of this approach by applying it to simulated data and to data obtained from a typical fMRI study.     

MCTD – Mixed Connective Tissue Disease

Mixed connective tissue disease is a disease entity characterized by overlapping symptoms of lupus erythematosus (LE), systemic sclerosis (SSc), polymyositis/dermatomyositis (PM/DM) and rheumatoid arthritis (RA). Diagnostic criteria include high titers of antibodies against U1RNP as well as the presence of at least 3 of 5 of the following clinical features: edema of hands, synovitis, myositis, Raynaud phenomenon and acrosclerosis. In terms of the pathogenesis, genetic as well as infectious (viral) factors appear to play a role. The acceptance of MCTD as a distinct disease entity is controversial. Terms such as ”undifferentiated connective tissue disease“ or ”overlapping syndromes“ are not helpful. One‐quarter of MCTD patients transform into LE, while one‐third progress to SSc. Therapeutic recommendations are glucocorticoids in combination with immunosuppressive agents and endothelin receptor antagonists. Double blind studies are not available. The prognosis is relatively good. Causes of death include pulmonary hypertension, infections and both pulmonary and cardiac failure.     

Prevention and treatment of cardiovascular disease in Ethiopia: a cost-effectiveness analysis

Background

The coverage of prevention and treatment strategies for ischemic heart disease and stroke is very low in Ethiopia. In view of Ethiopia’s meager healthcare budget, it is important to identify the most cost-effective interventions for further scale-up. This paper’s objective is to assess cost-effectiveness of prevention and treatment of ischemic heart disease (IHD) and stroke in an Ethiopian setting.

Methods

Fifteen single interventions and sixteen intervention packages were assessed from a healthcare provider perspective. The World Health Organization’s Choosing Interventions that are Cost-Effective model for cardiovascular disease was updated with available country-specific inputs, including demography, mortality and price of traded and non-traded goods. Costs and health benefits were discounted at 3 % per year. Incremental cost-effectiveness ratios are reported in US$ per disability adjusted life year (DALY) averted. Sensitivity analysis was undertaken to assess robustness of our results.

Results

Combination drug treatment for individuals having >35 % absolute risk of a CVD event in the next 10 years is the most cost-effective intervention. This intervention costs US$67 per DALY averted and about US$7 million annually. Treatment of acute myocardial infarction (AMI) (costing US$1000–US$7530 per DALY averted) and secondary prevention of IHD and stroke (costing US$1060–US$10,340 per DALY averted) become more efficient when delivered in integrated packages. At an annual willingness-to-pay (WTP) level of about US$3 million, a package consisting of aspirin, streptokinase, ACE-inhibitor and beta-blocker for AMI has the highest probability of being most cost-effective, whereas as WTP increases to > US$7 million, combination drug treatment to individuals having >35 % absolute risk stands out as the most cost-effective strategy. Cost-effectiveness ratios were relatively more sensitive to halving the effectiveness estimates as compared with doubling the price of drugs and laboratory tests.

Conclusions

In Ethiopia, the escalating burden of CVD and its risk factors warrants timely action. We have demonstrated that selected CVD intervention packages could be scaled up at a modest budget increase. The level of willingness-to-pay has important implications for interventions’ probability of being cost-effective. The study provides valuable evidence for setting priorities in an essential healthcare package for CVD in Ethiopia.

     

Level of action of cathodal DC polarisation induced inhibition of the human motor cortex.

OBJECTIVE: To induce prolonged motor cortical excitability reductions by transcranial direct current stimulation in the human. METHODS: Cathodal direct current stimulation was applied transcranially to the hand area of the human primary motor cortex from 5 to 9 min in separate sessions in twelve healthy subjects. Cortico-spinal excitability was tested by single pulse transcranial magnetic stimulation. Transcranial electrical stimulation and H-reflexes were used to learn about the origin of the excitability changes. Neurone specific enolase was measured before and after the stimulation to prove the safety of the stimulation protocol. RESULTS: Five and 7 min direct current stimulation resulted in motor cortical excitability reductions, which lasted for minutes after the end of stimulation, 9 min stimulation induced after-effects for up to an hour after the end of stimulation, as revealed by transcranial magnetic stimulation. Muscle evoked potentials elicited by transcranial electric stimulation and H-reflexes did not change. Neurone specific enolase concentrations remained stable throughout the experiments. CONCLUSIONS: Cathodal transcranial direct current stimulation is capable of inducing prolonged excitability reductions in the human motor cortex non-invasively. These changes are most probably localised intracortically.     

Caries treatment through 30 years in children and adolescents in Asker, Norway

Abstract Asker is a capital suburb where a preventive philosophy has guided the public dental health services for decades. In the period studied the child population aged 3–13 yr increased from 3208 to 6008. In the school age groups 7–15 yr practically all children in the community have participated in the dental service programs. The objective of the paper is to present retrospectively the changes in caries status of children under near optimal dental health care conditions and to expose reported preventive activities. A considerable increase in the proportion of “caries free” pre-school children occurred in the period 1976–88. A maximum was reached in the latter part of the eighties, where after a leveling off is suggested. For school children a rapid increase in “caries free” children took place for the lowest grades, starting before 1976. The higher grades came later and at a slower pace. The great number of fillings inserted in 1966–72, oscillating around 60 surfaces for the nine school years, decreased rapidly during the following decade and seems now to have settled around a total average of five to six surfaces. This implies a reduction of 90% in 20 yr. In most age groups these changes started before 1970. The major part of the caries decline occurred in the seventies and a leveling off is apparent during the eighties. The average number of filled surfaces per year has fallen from 6.6 in the 1955 birth cohort to 0.7 in the 1977 cohort, a reduction of 89% in 22 yr. The average number of filled surfaces (FS) in 15-yr-olds leaving compulsory school decreased during the period 1980–92 from 16.5 to 4.8. In 1980 20% of the children left school with more than 20 filled surfaces, as compared to only 3% in 1992. Operative treatment need has been reduced to a fairly low level among school children and adolescents, but caries is definitely not eradicated. The “caries free” situation is not permanent, but treatment need becomes evident at a later age and is more modest than before. The remarkable reduction and delay of the caries problem is most likely the result of several factors, fluorides seemingly playing the major role.