Cost-Effectiveness of Prevention for People at Risk for Dementia: A Scoping Review and Qualitative Synthesis

Dementia is from an economic perspective a main challenge for economies worldwide because of increasing costs. Since there is no cure in sight, prevention seems the most promising approach for reducing health care cost due to Dementia. On the contrary, approximately 40% of dementias is attributable to modifiable risk factors and first studies showed that multidomain interventions may be effective for preventing dementia. Considering the increasing economic burden, for many health administrations worldwide, cost-effectiveness plays a mayor role. This scoping review wants to bring evidence to the question if prevention for people at risk may be cost-effective. Therefore, the four databases Medline (via Pubmed), CINHAL (via EBSCO), Business Source Complete (via EBSCO), and the Health Economic Evaluation database (HEED) were used to conduct a scoping review using PICO and a systematic search string. 3,629 studies were identified and seven met all inclusion criteria. The included studies showed clear cost-effectiveness for most multidomain interventions. The gained QALYs at mean were 0.08 (SD=0.08) and the intervention average costs 472.20 EUR per Person (SD=74.06 EUR). The Incremental Cost-Effectiveness Ratios varied between -80,427.97 and 104,189.82 EUR per QALY. The three core results are (i) prevention programs focusing on people at risk may be cost-effective and cost-efficient, (ii) multimodal prevention reveal cost saving potential, when the people at risk are defined well, (iii prevention in middle-aged cohorts may be also cost-effective if life-style related risk factors are addressed.

Cold thermopeaking-induced drift of nase Chondrostoma nasus larvae

Research on how intermittent water releases from hydropower plants affect the early life stages of fish has advanced in the last years, focusing not only on the direct impacts of rapid flow changes (hydropeaking), but also on the short-term fluctuations in water temperature (thermopeaking). Flow and thermal fluctuations caused by hydropeaking may affect fish movement patterns and migration at critical stages of a species' life cycle, e.g., by inducing passive downstream drift. Using two experimental outdoor channels, we investigated how nase (Chondrostoma nasus, Cypriniformes) larvae respond to a rapid drop in water temperature during hydropeaking (simulating a cold thermopeaking event), reaching on average 5.5 °C under peak flow (maximum discharge) conditions, in comparison with a hydropeaking treatment with a constant water temperature regime. Responses of fish larvae were analyzed during acclimation, up-ramping (increase in discharge), peak flow and down-ramping (decrease in discharge) phases. Fish drift increased during peak flow in the cold thermopeaking treatment compared to hydropeaking. Higher drift rates were also negatively associated with pronounced water temperature drops during peak flow conditions. In addition, the starting temperature of the experiment influenced drift during up-ramping. Overall, the results suggest that cold thermopeaking may increase drift in the early life stages of cypriniform fish compared with hydropeaking with stable water temperature. Hence, monitoring and active water temperature adjustments following hydropower releases should be adopted as strategies to mitigate power plant-related impacts on aquatic organisms.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s00027-023-00955-x.

Evaluation of Mass Sensitive Micro-Array biosensors for their feasibility in multiplex detection of low molecular weight toxins using mycotoxins as model compounds

Mycotoxins produced by Fusarium species including trichothecenes, zearalenone and fumonisins, can co-contaminate food and feed throughout the supply chain, including cereal grains and animal feeds. There is an increasing demand to enhance global food security by improving the monitoring of mycotoxins throughout our food supply chain. For time and cost-efficient analysis, rapid tests capable of detecting multiple toxins from a single sample are ideal. Considering these current trends in mycotoxin testing, this project examined the feasibility of using both a portable and non-portable mass-based biosensor for multiplex mycotoxin detection. The biosensor was a mass sensitive microarray (MSMA) which consisted of 4 × 16 miniaturized mass sensitive transducer pixels based on solidly mounted resonator (SMR) technology. Functionalisation of individual pixels on the sensor surface using nano-spotting technology for the simultaneous and semi-quantitative detection of three regulated mycotoxins: T2-toxin (T2) zearalenone (ZEN), and fumonisin B1 (FumB1) was examined. With the integration of portable and non-portable microfluidic devices for antibody and standard sample injections, competitive inhibition assays were developed followed by singleplex and multiplex calibration curves. The characteristics and performance of the MSMA were evaluated including sensitivity which was determined as the concentration causing 50% inhibition. Sensitivity of singleplex assays using the portable microfluidic device (PMD) were 1.3 ng/ml, 2.0 ng/ml and 6.8 ng/ml for T2, FumB1 and ZEN, respectively. Sensitivity of the multiplex assay again using the PMD was 6.1 ng/ml, 3.6 ng/ml and 2.4 ng/ml for T2, FumB1 and ZEN, respectively. The PMD was an easy to use and highly sensitive screening tool which has been demonstrated for the multiplex detection of three regulated mycotoxins. Analysis was in real time and results were fully digital. Since detection of analytes was by mass it was both a label-free and cost-efficient method proposed method of analysis for mycotoxins.

Regarding loads after spinal fusion, every level should be seen separately: a musculoskeletal analysis

INTRODUCTION

The number of spinal fusion surgeries is steadily increasing and biomechanical consequences are still in debate. The aim of this study is to provide biomechanical insights into the sagittal balance of the spine and to compare spinal load before and after spinal fusion.

METHOD

The joint reaction forces of 52 patients were analyzed in proximo-distal and antero-posterior direction from the levels T12-L1 to L5-S1 using musculoskeletal simulations.

RESULTS

In 104 simulations, pre-surgical forces were equal to post-surgical. The levels L4-L5 and T12-L1, however, showed increased spinal forces compression forces with higher sagittal displacement. Improved restauration of sagittal balance was accompanied by lower spinal load. AP shear stress, interestingly decreased with sagittal imbalance.

CONCLUSION

Imbalanced spines have a risk of increased compression forces at Th12-L1. L4-L5 always has increased spinal loads. These slides can be retrieved under Electronic Supplementary Material.

Importance of non-affine viscoelastic response in disordered fibre networks

Disordered fibre networks are ubiquitous in nature and have a wide range of industrial applications as novel biomaterials. Predicting their viscoelastic response is straightforward for affine deformations that are uniform over all length scales, but when affinity fails, as has been observed experimentally, modelling becomes challenging. Here we present a numerical methodology, related to an existing framework for amorphous packings, to predict the steady-state viscoelastic spectra and degree of affinity for disordered fibre networks driven at arbitrary frequencies. Applying this method to a peptide gel model reveals a monotonic increase of the shear modulus as the soft, non-affine normal modes are successively suppressed as the driving frequency increases. In addition to being dominated by fibril bending, these low frequency network modes are also shown to be delocalised. The presented methodology provides insights into the importance of non-affinity in the viscoelastic response of peptide gels, and is easily extendible to all types of fibre networks.

Amyloid Fibril Solubility

It is well established that amyloid fibril solubility is protein specific, but how solubility depends on the interactions between the fibril building blocks is not clear. Here we use a simple protein model and perform Monte Carlo simulations to directly measure the solubility of amyloid fibrils as a function of the interaction between the fibril building blocks. Our simulations confirms that the fibril solubility depends on the fibril thickness and that the relationship between the interactions and the solubility can be described by a simple analytical formula. The results presented in this study reveal general rules how side-chain-side-chain interactions, backbone hydrogen bonding, and temperature affect amyloid fibril solubility, which might prove to be a powerful tool to design protein fibrils with desired solubility and aggregation properties in general.

Universality in the morphology and mechanics of coarsening amyloid fibril networks

Peptide hydrogels have important applications as biomaterials and in nanotechnology, but utilization often depends on their mechanical properties for which we currently have no predictive capability. Here we use a peptide model to simulate the formation of percolating amyloid fibril networks and couple these to the elastic network theory to determine their mechanical properties. We find that the time variation of network length scales can be collapsed onto master curves by using a time scaling function that depends on the peptide interaction anisotropy. The same scaling applies to network mechanics, revealing a nonmonotonic dependence of the shear modulus with time. Our structure-function relationship between the peptide building blocks, network morphology, and network mechanical properties can aid in the design of amyloid fibril networks with tailored mechanical properties.

Development of the nano-dust analyzer (NDA) for detection and compositional analysis of nanometer-size dust particles originating in the inner heliosphere

A linear time-of-flight mass spectrometer is developed for the detection and chemical analysis of nanometer-sized particles originating near the Sun. Nano-dust particles are thought to be produced by mutual collisions between interplanetary dust particles slowly spiraling toward the Sun and are accelerated outward to high velocities by interaction with the solar wind plasma. The WAVES instruments on the two STEREO spacecraft reported the detection, strong temporal variation, and potentially high flux of these particles. Here we report on the optimization and the results from the detailed characterization of the instrument's performance using submicrometer sized dust particles accelerated to 8-60 km/s. The Nano Dust Analyzer (NDA) concept is derived from previously developed detectors. It has a 200 cm(2) effective target area and a mass resolution of approximately m/Δm = 50. The NDA instrument is designed to reliably detect and analyze nanometer-sized dust particles while being pointed close to the Sun's direction, from where they are expected to arrive. Measurements by such an instrument will determine the size-dependent flux of the nano-dust particles and its variations, it will characterize the composition of the nano-dust and, ultimately, it may determine their source. The flight version of the NDA instrument is estimated to be <5 kg and requires <10 W for operation.

[A training program for dementia trainers: does this program have practical relevance?]

BACKGROUND

Specific curricula for professionals working in various settings with persons with dementia have been developed and implemented into practice. In this study, the practical relevance of a teaching program for the M.A.S (Morbus Alzheimer syndrome) dementia trainer was evaluated. The curriculum was developed in 2002 within a scientific project. The goal was that care professionals and noncare professionals learn how to support and train persons with dementia and their caregivers. The task of the trainer is to support the functional and emotional resources of the person with dementia employing stage-specific training according to principles of the theory of retrogenesis. Trainers are also able to support family caregivers in their difficult day-to-day care for the person with dementia. With this training and support program, persons with dementia can train their residual capacities and develop a life perspective which enables them to cope with the long duration of Alzheimer's disease.

MATERIALS AND METHODS

The curriculum for the training methodology is based in the theory of retrogenesis. The 1-year training course is held in the form of modules and includes the following topics: (1) stages of dementia and medical aspects, (2) communication with persons with dementia, (3) stage-specific retrogenic training, (4) physical training for the elderly and persons with dementia, (5) coaching family caregivers through the long disease duration, and (6) care issues for persons without education in care. M.A.S trainers were questioned after they had concluded the teaching program successfully and had the chance to apply the content of the teaching program in their practical work. A short questionnaire was sent via e-mail or a telephone interview was performed.

RESULTS

A total of 279 trainers graduated and were certified. Of these, 140 persons (53.6% of the population) could be questioned after an average of 2.69 years after completion of the course: 93.6% of trainees were still using the principles of the teaching course successfully; of these, 56% were working in the function of a trainer full time and 44% used the principles within their work environment (mainly in the nursing home environment).

CONCLUSION

The study found that the majority of questioned trainers are still using the principles taught in the course successfully with persons with dementia living at home and the content was found to be relevant for practice. The content of the teaching course, applying principles of retrogenesis, which was originally designed for persons with dementia living at home, can also be successfully applied in the nursing home environment. Increasing interest has been shown by institutions employing professionals whose task it is to keep persons with dementia active and interested as well as physically functioning at their best possible level. As a consequence, persons with dementia perceive higher quality of life and exhibit fewer behavior problems which complicate care. More research is needed to accumulate evidence and to support these findings.

Dust trajectory sensor: accuracy and data analysis

The Dust Trajectory Sensor (DTS) instrument is developed for the measurement of the velocity vector of cosmic dust particles. The trajectory information is imperative in determining the particles' origin and distinguishing dust particles from different sources. The velocity vector also reveals information on the history of interaction between the charged dust particle and the magnetospheric or interplanetary space environment. The DTS operational principle is based on measuring the induced charge from the dust on an array of wire electrodes. In recent work, the DTS geometry has been optimized [S. Auer, E. Grün, S. Kempf, R. Srama, A. Srowig, Z. Sternovsky, and V Tschernjawski, Rev. Sci. Instrum. 79, 084501 (2008)] and a method of triggering was developed [S. Auer, G. Lawrence, E. Grün, H. Henkel, S. Kempf, R. Srama, and Z. Sternovsky, Nucl. Instrum. Methods Phys. Res. A 622, 74 (2010)]. This article presents the method of analyzing the DTS data and results from a parametric study on the accuracy of the measurements. A laboratory version of the DTS has been constructed and tested with particles in the velocity range of 2-5 km/s using the Heidelberg dust accelerator facility. Both the numerical study and the analyzed experimental data show that the accuracy of the DTS instrument is better than about 1% in velocity and 1° in direction.

Nursing home structure and association with agitation and use of psychotropic drugs in nursing home residents in three countries: Norway, Austria and England

BACKGROUND

Understanding the underlying mechanisms and risk factors leading to agitation is crucial to reduce the severity of agitation and increase quality of life. International comparative studies offer special advantages in elucidating environmental risk factors by providing a wider diversity of environmental exposures such as nursing home structures, health care systems and genetic diversity.

METHODS

Baseline data for three different intervention studies in Austria (n = 38), England (n = 302) and Norway (n = 163) were combined posthoc. Patients were grouped according to their dementia severity using the global deterioration scale (GDS), functional assessment staging (FAST) and clinical dementia rating (CDR) scales. For the measurement of agitation, the Cohen-Mansfield Agitation Inventory (CMAI) was used. Data analysis was performed using one-way ANOVA, multivariate and linear regression analysis.

RESULTS

CMAI scores were available for 503 subjects with dementia. There were significant differences between the nursing home residents in the three countries regarding age, gender and dementia severity (all p values < 0.001). In the multivariate analyses, the level of agitation differed with higher mean scores in the Austrian (mean (SD) score 51.9(21.8)) compared to UK (43.3(16.1)) and Norwegian (41.6(13.2)) nursing homes (p = 0.002). Similarly, the use of psychotropic drugs differed significantly, with a higher proportion of neuroleptics in UK (48%, p < 0.001) and Austrian (52.6%; p = 0.001) compared to Norwegian (19%) nursing homes.

CONCLUSION

We found differences in agitation and antipsychotic drug use which are likely related to structural and cultural differences in nursing homes in three European countries. These findings suggest that structural changes can improve quality of care and quality of life for nursing home residents.

Structure-function studies of a Melanocarpus albomyces laccase suggest a pathway for oxidation of phenolic compounds

Melanocarpus albomyces laccase crystals were soaked with 2,6-dimethoxyphenol, a common laccase substrate. Three complex structures from different soaking times were solved. Crystal structures revealed the binding of the original substrate and adducts formed by enzymatic oxidation of the substrate. The dimeric oxidation products were identified by mass spectrometry. In the crystals, a 2,6-dimethoxy-p-benzoquinone and a C-O dimer were observed, whereas a C-C dimer was the main product identified by mass spectrometry. Crystal structures demonstrated that the substrate and/or its oxidation products were bound in the pocket formed by residues Ala191, Pro192, Glu235, Leu363, Phe371, Trp373, Phe427, Leu429, Trp507 and His508. Substrate and adducts were hydrogen-bonded to His508, one of the ligands of type 1 copper. Therefore, this surface-exposed histidine most likely has a role in electron transfer by laccases. Based on our mutagenesis studies, the carboxylic acid residue Glu235 at the bottom of the binding site pocket is also crucial in the oxidation of phenolics. Glu235 may be responsible for the abstraction of a proton from the OH group of the substrate and His508 may extract an electron. In addition, crystal structures revealed a secondary binding site formed through weak dimerization in M. albomyces laccase molecules. This binding site most likely exists only in crystals, when the Phe427 residues are packed against each other.

Large area mass analyzer instrument for the chemical analysis of interstellar dust particles

A new instrument to analyze the chemical composition of dust particles in situ in space has been developed. The large target area ( approximately 0.2 m(2)) makes this instrument well suited for detecting a statistically significant number of interstellar dust grains or other dust particles with a low flux. The device is a reflectron-type time-of-flight mass spectrometer that uses only flat electrodes for the generation of the parabolic potential. The instrument analyzes the ions from the impact generated plasma due to hypervelocity dust impacts onto a solid target surface. The SIMION ion optics software package is used to investigate different potential field configurations and optimize the mass resolution and focusing of the ions. The cylindrically symmetric instrument operates with six ring electrodes and six annular electrodes biased to different potentials to create the potential distribution of the reflectron. The laboratory model of the instrument has been fabricated and tested. Hypervelocity dust impacts are simulated by laser ablation using a frequency doubled Nd:YAG laser with approximately 8 ns pulse length. The experimental data show typical mass resolution m/Deltam approximately 200.

Breakdown of classical nucleation theory near isostructural phase transitions

We report simulations of crystal nucleation in binary mixtures of hard spherical colloids with a size ratio of 1:10. The stable crystal phase of this system can be either dense or expanded. We find that, in the vicinity of the solid-solid critical point where the crystallites are highly compressible, small crystal nuclei are less dense than large nuclei. This phenomenon cannot be accounted for by either classical nucleation theory or by the Gibbsian droplet model. We argue that the observed behavior is due to the surface stress of the crystal nuclei. The observed effect highlights a general deficiency of the most frequently used thermodynamic theories for crystal nucleation. Surface stress should lead to an experimentally observable expansion of crystal nuclei of colloids with short-ranged attraction and of globular proteins.

Onset of heterogeneous crystal nucleation in colloidal suspensions

The addition of small 'seed' particles to a supersaturated solution can greatly increase the rate at which crystals nucleate. This process is understood, at least qualitatively, when the seed has the same structure as the crystal that it spawns. However, the microscopic mechanism of seeding by a 'foreign' substance is not well understood. Here we report numerical simulations of colloidal crystallization seeded by foreign objects. We perform Monte Carlo simulations to study how smooth spherical seeds of various sizes affect crystallization in a suspension of hard colloidal particles. We compute the free-energy barrier associated with crystal nucleation. A low barrier implies that nucleation is easy. We find that to be effective crystallization promoters, the seed particles need to exceed a well-defined minimum size. Just above this size, seed particles act as crystallization 'catalysts' as newly formed crystallites detach from the seed. In contrast, larger seed particles remain covered by the crystallites that they spawn. This phenomenon should be experimentally observable and can have important consequences for the control of the resulting crystal size distribution.

Numerical prediction of absolute crystallization rates in hard-sphere colloids

Special computational techniques are required to compute absolute crystal nucleation rates of colloidal suspensions. Using crystal nucleation of hard-sphere colloids as an example, we describe in some detail the novel computational tools that are needed to perform such calculations. In particular, we focus on the definition of appropriate order parameters that distinguish liquid from crystal, and on techniques to compute the kinetic prefactor that enters in the expression for the nucleation rate. In addition, we discuss the relation between simulation results and theoretical predictions based on classical nucleation theory.

[Central case management in surgery]

Up to now, in most surgical departments there has been no central patient management coordinating the admission, the diagnostic work-up, and the surgical procedures of patients with the resources available in the hospital. In future, however, it will be essential for surgical departments to establish such a central patient management, not only in view of the importance of patient-oriented medicine but also considering the planned introduction of diagnosis related groups. A central patient management will reduce preoperative and overall length of stay through adequate organisation and communication structures. In addition, a central patient management will make optimal use of the available resources in terms of operation rooms and hospital beds. In this article, we will present our basic concept of a central patient management in a surgical university department.

Line tension controls wall-induced crystal nucleation in hard-sphere colloids

We report on a numerical study of the effect of a smooth, hard wall on the crystallization of hard-sphere colloids. We find that the presence of the wall drastically lowers the barrier for crystal nucleation, but it does not eliminate it. Crystal nucleation becomes noticeable at pressures that are some 5% above the coexistence value. The first particles to crystallize on the wall form a (111) plane. Initially, this crystallite grows laterally, rather than in the third dimension. The free energy of the critical crystal nucleus on the wall is about 2 orders of magnitudes lower than in the bulk. Analysis of the numerical data indicates that, at coexistence, the (111) plane is at the threshold of wetting the wall. The nucleation barrier is dominated by line tension.

Phase behavior and crystallization kinetics of poly-12-hydroxystearic-coated polymethylmethacrylate colloids

Polymethylmethacrylate (PMMA) colloids sterically stabilized by a layer of chemically grafted poly-12-hydroxystearic (PHSA) are widely used in experiments as model hard spheres. However, due to the coating, the interaction between particles is slightly soft. Here we report a numerical study of the effect of the PHSA coating on the phase behavior and crystallization kinetics of PMMA colloids based on parameters determined from surface-force measurements on PHSA-PMMA-coated mica surfaces [B. A. de L. Costello and P. F. Luckham, J. Colloid Interface Sci. 156, 72 (1993); B. A. de L. Costello et al., Langmuir 8, 464 (1992)]. We find that the core volume fraction of particles at freezing measured by Pusey and van Megen [Nature 320, 340 (1986)] can only be reproduced by using a thickness of the PHSA layer that is considerably larger than literature values. This may indicate that the particles are in fact slightly charged. Compared to perfect hard spheres, the crystallization rate in these slightly soft particles was found to be increased by about two orders of magnitudes.

[Central patient management in surgery]

Up to now, in most surgical departments there has been no central patient management coordinating the admission, the diagnostic work-up, and the surgical procedures of patients with the resources available in the hospital. In future, however, it will be essential for surgical departments to establish such a central patient management, not only in view of the importance of patient-oriented medicine but also considering the planned introduction of diagnosis related groups. A central patient management will reduce preoperative and overall length of stay through adequate organisation and communication structures. In addition, a central patient management will make optimal use of the available resources in terms of operation rooms and hospital beds. In this article, we will present our basic concept of a central patient management in a surgical university department.

Suppression of crystal nucleation in polydisperse colloids due to increase of the surface free energy

The formation of small crystallites is governed by two competing factors: the free energy gained upon transferring constituent atoms, molecules or colloidal particles from the metastable liquid to the more stable solid, and the free energy needed to create the surface area of the crystallite. Because the ratio of surface area to bulk is large for small particles, small crystallites dissolve spontaneously under conditions where larger crystallites are stable and macroscopic crystal growth occurs only if spontaneously formed crystallites exceed a critical minimum size. On theoretical grounds, the probability of forming such critical crystal nuclei is expected to increase rapidly with supersaturation. However, experiments show that the rate of crystal nucleation in many systems goes through a maximum as the supersaturation is increased. It is commonly assumed that the nucleation rate peaks because, even though the probability of forming critical nuclei increases with increasing concentration, the rate of growth of such nuclei decreases. Here we report simulations of crystal nucleation in suspensions of colloidal spheres with varying size distributions that show that the probability that critical nuclei will form itself goes through a maximum as the supersaturation is increased. We find that this effect, which is strongest for systems with the broadest particle size distribution, results from an increase with supersaturation of the solid-liquid interfacial free energy. The magnitude of this effect suggests that vitrification at high supersaturations should yield colloidal glasses that are truly amorphous, rather than nano-crystalline.

Prediction of absolute crystal-nucleation rate in hard-sphere colloids

Crystal nucleation is a much-studied phenomenon, yet the rate at which it occurs remains difficult to predict. Small crystal nuclei form spontaneously in supersaturated solutions, but unless their size exceeds a critical value--the so-called critical nucleus--they will re-dissolve rather than grow. It is this rate-limiting step that has proved difficult to probe experimentally. The crystal nucleation rate depends on Pcrit, the (very small) probability that a critical nucleus forms spontaneously, and on a kinetic factor (kappa) that measures the rate at which critical nuclei subsequently grow. Given the absence of a priori knowledge of either quantity, classical nucleation theory is commonly used to analyse crystal nucleation experiments, with the unconstrained parameters adjusted to fit the observations. This approach yields no 'first principles' prediction of absolute nucleation rates. Here we approach the problem from a different angle, simulating the nucleation process in a suspension of hard colloidal spheres, to obtain quantitative numerical predictions of the crystal nucleation rate. We find large discrepancies between the computed nucleation rates and those deduced from experiments: the best experimental estimates of Pcrit seem to be too large by several orders of magnitude.

Progression of Alzheimer's disease: variability and consistency: ontogenic models, their applicability and relevance

Much has been learned about the clinical symptomatology of Alzheimer's disease (AD) and ontogenic reciprocal relationships in the past few decades. It is now possible to describe and verify inexorable symptomatic sequences and corresponding temporal relationships. It is also possible to identify more variable symptoms in AD. Ontogenic models can be useful in providing a clearer understanding of the nature of AD symptomatology in terms of both consistency and variability. These models can also be informative in explicating the management needs of AD patients and the treatment possibilities of AD symptoms as well as the etiology of variability in AD symptoms.

The GDS/FAST staging system

Staging methodologies are an essential tool in the assessment of disease severity in progressive dementing illness. Several different instruments have been developed for this purpose. One of the most widely used methodologies is the Global Deterioration Scale/Functional Assessment Staging (GDS/FAST) system. This system has been studied extensively and proven to be reliable and valid for staging dementia in Alzheimer's disease (AD) in diverse settings. One of the major advantages of this system is that it spans, demarcates, and describes the entire course of normal aging and progressive AD until the final substages of the disease process. Other advantages include: (a) greatly enhanced ability to track the longitudinal course of AD, (b) improved clinicopathologic observations of AD interrelationships, and (c) enhanced diagnostic, differential diagnostic, and prognostic information. This article presents a brief overview of the GDS/FAST staging system.

The use of Baypamun N in crowding-associated infectious respiratory disease: efficacy of Baypamun N (freeze dried product) in 2-week-old veal calves

The efficacy of an immunomodulator, Baypamun N, was tested in 10-20-day-old veal calves from different farms, which were exposed to stress by transport and commingling (crowding). Verum and placebo animals (n = 50, each group) received three intramuscular injections of the investigational products (days 0, 2, 4) starting the day of arrival on the farm. Data from 49 calves in each group could be used for statistical evaluation. The incidence of acute bovine respiratory disease was anticipated to be high during the first 2 weeks after arrival on farm based on experience from other years. The clinical scores in the Baypamun N group were significantly reduced by 52.7% (P < 0.001) compared to the placebo group. The number of antibiotic treatments was significantly reduced by 53.8% (P < 0.001) in the Baypamun N group. Of the calves treated with Baypamun N, 51.02% remained untreated with antibiotics during the first 2 weeks after arrival on the farm compared with only 16.3% of the placebo treated control calves (P < 0.001).

A gE deleted infectious bovine rhinotracheitis marker vaccine for use in improved bovine herpesvirus 1 control programs

Based on a glycoprotein E (gE) deleted bovine herpesvirus 1 (BHV1) strain (Kaashoek et al., 1994) a killed virus as well as a modified live virus marker vaccine have been developed that allow differentiation between immunized and BHV1 infected cattle. Safety and efficacy of both vaccines were tested extensively following the current European Union (EU) requirements for the development of bovine vaccines. The minimum vaccine dose, vaccination regimen, route of administration and duration of immunity were evaluated for both vaccines in comprehensive vaccination/challenge trials in cattle. The most potent adjuvant formulation for the killed virus vaccine was also selected by experimental challenge infections. For the modified live virus marker vaccine it could be demonstrated that maternally derived BHV1 specific antibodies did not interfere with vaccination. Safety could be demonstrated for both the killed virus and the modified live virus vaccine in all target animal categories including veal calves, beef cattle, bulls, heifers and dairy cattle, including pregnant animals.

Overview of methodologic issues for pharmacologic trials in mild, moderate, and severe Alzheimer's disease

To address the issue of mild, moderate, and severe Alzheimer's disease (AD), it is necessary to initially establish some agreement on terminology. In recent decades, these terms have frequently been defined using screening instrument scores with measures such as the Mini-Mental State Examination (MMSE). There are many problems with this approach, perhaps the most salient of which is that it has contributed to the total and tragic neglect of patients with severe AD. An alternative approach to the classification of AD severity is staging. This approach has advanced to the point where moderately severe and severe AD can be described in detail. Procedures for describing this previously neglected latter portion of AD have recently been extensively validated. Staging is also uniquely useful at the other end of the severity spectrum, in differentiating early aging brain/behavior changes, incipient AD, and mild AD. Temporally, with staging procedures, it is possible to track the course of AD approximately three times more accurately than with the MMSE. The net result of the advances in AD delineation is that issues such as prophylaxis, modification of course, treatment of behavioral disturbances, loss of ambulation, progressive rigidity, and the development of contractures in AD patients can now be addressed in a scientifically meaningful way that will hopefully bestow much benefit in AD patients and those who care for them.

Polarization-sensitive spectroradiometer: two methods for overcoming the problems of measuring reflectance spectra

The spectra obtained using a spectroradiometer are incorrect if the incident light from the sample is polarized, and if, at the same time, polarization is introduced into the transmitted beam by components of the spectroradiometer. Two methods are proposed for obtaining correct power reflectance spectra. One way is to average two incorrect reflectance spectra, which are taken at mutually orthogonal angles of rotation of the radiometer about its optical axis. Another way is by averaging reflectance spectra of mutually orthogonal polarized light components. When the orientation of one component is chosen such that it is in the plane of polarization of the incoming light, the latter method also gives the correct degree of polarization.