Using simulation mannequins and actors in training for external post-mortem examinations -experiences from use in medical students and police officers.

In the daily practice of external post-mortem examinations and dealing with surviving dependents, striking failures can be observed regularly, pointing to an increased demand for training of the various professional groups involved. In this study, the experience gained from using simulation mannequins and actors for post-mortem examination training in medical students and police officers are presented. Since 2017, a training station has been offered at the Medical Faculty of the Technical University of Dresden (Germany) for practicing examinations in death scene and establishing communication with grieving relatives. It is conducted in small groups of up to 5 people, both for medical students and for police officers and police recruits. These courses are evaluated by means of questionnaires including 3 and 11 items respectively for the different groups. The questionnaires have been completed by 679 medical students and 67 police participants. Both groups of participants evaluated their previous experience as average. They assessed the course as having a high degree of practical and professional relevance. The didactic transfer of the teaching contents and its competent support were rated remarkably positive by the participants. Additionally, the police group reported high rates of approval for the use of feedback, the learning effect, and the appropriateness of the group size. The establishment and continuation of the simulation-based external post-mortem examination in the form of small-group teaching is associated with a considerable expenditure of equipment, material and personnel. In addition, its implementation requires sound cooperation structures. On the other hand, introduction and continuation of these types of additional teaching and learning methods, with a large practical component, can increase confidence in daily practice, and thus improve the quality of external post-mortem examination. Ultimately, this can also improve the cooperation between forensic medicine and the investigating authorities.

Characteristics of inline speedskating--incremental tests and effect of drafting.

Competitive inline speedskating combines a movement pattern similar to speedskating on ice with pack-oriented competition modes known from cycling. The deep-seated body position leads to high static load and, thus, restricted blood flow within propulsive muscles. This condition may affect lactate kinetics and limit V.O (2peak). The present study compares physiologic reactions to graded cycling and skating exercise among top-level inline speedskaters and quantifies the effect of drafting. Eight male inline speedskaters of the top national level were examined. The study consisted of two graded exhaustive exercise tests (cycling and speedskating) and a pairwise drafting test. All tests were carried out with simultaneous gas exchange (MetaMax 2, Cortex, Germany) and heart rate measurements as well as determination of blood lactate concentrations. Maximal values of oxygen consumption (cycling: 4.91 +/- 0.60; skating: 4.85 +/- 0.50 l . min (-1); p = 0.78), lactate concentration, or heart rate were similar for cycling and skating. At workloads corresponding to blood lactate concentrations of 4 mmol . l (-1) oxygen uptake (cycling: 3.24 +/- 0.65; skating: 3.97 +/- 0.40 l . min (-1); p < 0.05) and heart rate (cycling: 162 +/- 9; skating: 173 +/- 6 min (-1); p < 0.05) were significantly higher during skating. The differences in heart rate ranged between - 2 and 23 min (-1). The drafting effect was 15 +/- 6 % at 30 km . h (-1) (3.34 +/- 0.19 vs. 2.83 +/- 0.29 l . min (-1)) and 14 +/- 5 % at 33 km . h (-1) (3.87 +/- 0.26 vs. 3.32 +/- 0.27 l . min (-1)). During inline speedskating the attainment of VO2peak is not impaired when compared to cycling exercise. However, the derivation of exercise prescriptions from a stepwise cycling test does not seem appropriate. The drafting effect of inline speedskating is within the range known from cycling.

Micro-scale measurement of the mechanical properties of compressed pharmaceutical powders. 2: The dynamic moduli of microcrystalline cellulose.

The use of two 'micro-scale' dynamic mechanical testing techniques for determining the viscoelastic properties of very small microcrystalline cellulose compacts ( approximately 20 mg) is reported. The first method is a simple tensile 'stretching' test, and the second is a dynamic version of the three-point beam-bending technique. For both approaches the storage (elastic) and loss (viscous) moduli could be readily determined for compacts of a wide range of porosities. The experimentally determined storage moduli were consistently one order of magnitude greater than the corresponding loss moduli indicating a dominating elastic response for the microcrystalline cellulose compacts. The moduli determined using the oscillating three-point beam-bending technique were slightly lower than expected and this was attributed to sample anisotropy and imperfect sample alignment/friction during testing. The moduli obtained using the simple dynamic tension tests were practically identical to complex moduli values reported for much larger specimens, and it appears that this technique is well suited to measuring the dynamic mechanical properties of very small pharmaceutical powder compacts.

Micro-scale measurement of the mechanical properties of compressed pharmaceutical powders. 1: The elasticity and fracture behavior of microcrystalline cellulose.

The feasibility of using very small compacts ( approximately 8.0 x 4.5 x 0.4 mm; approximately 20 mg) to determine the elasticity and fracture behavior of compressed pharmaceutical powders using the three-point beam-bending technique was evaluated. Compacts of microcrystalline cellulose with a range of porosities were tested using a thermomechanical analyzer and values for the Young's modulus and critical stress intensity factor at zero porosity (E(0) and K(IC0)) were determined by extrapolation. The value of E(0) measured at ambient relative humidity on un-notched beams was found to be in close agreement with that reported for much larger samples, and the value of K(IC0) for the small notched compacts was at the lower limit of the accepted range of values for microcrystalline cellulose. The fracture toughness (R) and total energy of fracture (U) for the notched specimens were also determined and used to estimate the apparent surface energies for crack initiation (gamma(i)) and for total fracture (gamma(f)). To further probe the utility of the micro-scale mechanical testing techniques, the effects of humidity on the various mechanical properties of the small microcrystalline compacts were examined and it was found that E(0), K(IC0), R(0), gamma(i0) and gamma(f0) each decreased as the surrounding humidity (and water content of the samples) increased.

Crystallization inhibition in solid dispersions of MK-0591 and poly(vinylpyrrolidone) polymers.

The effects of poly(vinylpyrrolidone) (PVP) molecular weight, composition, and content on the crystallization of a model drug, MK-0591 (Form I), were investigated. Solid dispersions of crystalline MK-0591 with PVP homopolymers of different molecular weights (2500-1 x 10(6) g/mol) and with a copolymer containing poly(vinyl acetate) (PVA), (PVP/VA, 60:40, 5.8 x 10(4) g/mol) were prepared by the solvent method. MK-0591 in the solid dispersions was found to be X-ray amorphous. One glass transition temperature (T(g)) was observed suggesting drug-polymer miscibility. The T(g) values were higher than predicted by the Gordon-Taylor equation, indicating drug-polymer interactions. The extent of crystallization inhibition increased with PVP molecular weight and, for a comparable PVP molecular weight, the homopolymer was more effective in the crystallization inhibition of the drug than the copolymer. The first onset temperature of crystallization (T(c)(obs)) increased with polymer content. The T(c)(obs) values (normalized to polymer content) were a function of the difference between the T(g) of the polymer and drug. For PVP K-90, K-30, and K-17 dispersions, the T(c)(obs) values increased proportionally to the T(g) of the dispersions. However, for PVP K-12 and PVP/VA, the increase in T(c)(obs) values corresponded to a small decrease in the T(g) values of the dispersions. This result suggests that additional factors other than the reduction in mobility affect the crystallization behavior of MK-0591 in the solid dispersions, such as specific interactions. By Fourier transform-infrared spectroscopy, changes in the carbonyl-stretching band of PVP in the solid dispersions were observed. The existence of an ion-dipole interaction between COO(-)Na(+) of the drug and the cyclic amide group of PVP was postulated.

Oxidative bioactivation of the lactol prodrug of a lactone cyclooxygenase-2 inhibitor.

The lactol derivative of a lactone cyclooxygenase-2 inhibitor (DFU) was evaluated in vivo and in vitro for its potential suitability as a prodrug. DFU-lactol was found to be 10 to 20 times more soluble than DFU in a variety of aqueous vehicles. After administration of DFU-lactol at 20 mg kg-1 p.o. in rats, a Cmax of 7.5 microM DFU was reached in the plasma. After oral administration, the ED50s of DFU-lactol in the carrageenan-induced paw edema and lipopolysaccharide-induced pyresis assays in rats are comparable with the ED50s observed when dosing with DFU. Incubations of DFU-lactol with rat and human hepatocytes demonstrated that the oxidation of DFU-lactol can be mediated by liver enzymes and that a competing pathway is direct glucuronidation of the DFU-lactol hydroxyl group. Assays with subcellular fractions from rat liver indicated that most of the oxidation of DFU-lactol occurs in the cytosolic fraction and requires NAD(P)+. Human liver cytosol can also support the oxidation of DFU-lactol to DFU when NAD(P)+ is added to the incubations. Fractionation of human liver cytosolic proteins showed that at least three enzymes are capable of efficiently effecting the oxidation of DFU-lactol to DFU. Incubations with commercially available dehydrogenases suggest that alcohol and hydroxysteroid dehydrogenases are involved in this oxidative process. These data together suggest that lactols may represent useful prodrugs for lactone-containing drugs.

Increasing the in vitro bile acid binding capacity of diethylaminoethylcellulose by quaternization.

Diethylaminoethylcellulose (DEAE-cellulose) was quaternized with methyl iodide (DEAE-cellulose-CH3I), and its in vitro binding capacity for sodium glycocholate, at room temperature, in water, Tris-HCl buffer (0.0015-0.0050 M, pH 7.0), and aqueous NaCl (0.0025 M) was determined by reversed-phase HPLC. Quaternization increased the in vitro bile salt binding capacity of DEAE-cellulose. On a molar basis, the binding capacity was greater than that of cholestyramine, a cholesterol-lowering agent. Increasing the ionic strength of the medium decreased the binding capacities, as expected if ionic interactions are important. However, conversion of DEAE-cellulose-CH3I to its chloride form did not change the binding capacity. The bile salt binding capacity of DEAE-cellulose-CH3I was similar for both sodium cholate and sodium glycocholate.

Quaternized colestipol, an improved bile salt adsorbent: in vitro studies.

Colestipol.HCl (col-HCl) was quaternized with methyl iodide to form col-CH3l. The in vitro binding capacities of the quaternized and protonated resins in water and in Tris-HCl buffer (0.0015 and 0.0025 M, pH 7.0) at approximately 22 degrees C for sodium glycocholate (NaGC) was determined by reversed-phase HPLC. The binding capacities were found to depend on the adsorption medium. In water, the binding capacity of col-CH3l was 30% greater than that of its protonated form. In Tris-HCl buffer at pH 7.0, the binding capacities of the resins were similar. When the quaternized colestipol was converted to its chloride form, the binding capacity for NaGC in Tris-HCl increased significantly and was 30% greater than that for its protonated analogue. In Cotazym 65B-water, a medium used to test the binding capacity of the resins in the presence of various agents (to try to simulate intestinal conditions), the binding capacity of the quaternized resin was again greater than that of its protonated form. Quaternization thus increases the in vitro binding capacity of colestipol for the glycocholate anion.

Polymer resins with amino acid containing pendants for sorption of bilirubin. IV. Site binding constants.

Site binding constants, calculated for the adsorption of bilirubin onto various lysine, arginine, or histidine containing oligopeptide-resins assuming either a one or two site binding model, are of the order of 10(4) M-1. Using these data it can be shown that there are positive cooperative effects for lysine-containing pendants, while arginine-containing pendants eventually result in negative cooperative behaviour. This difference in behaviour has been attributed to the difference in the side groups in the arginine and lysine pendants and is discussed in terms of the basicity of the amino acids, accessibility to the sites as a consequence of the flexibility or rigidity of the side group, and in terms of pi-pi electron interactions, where applicable.

Polymer resins with amino acid containing pendants for sorption of bilirubin. III. Adsorption and desorption in the presence of albumin.

The adsorption of bilirubin from aqueous phosphate buffer solutions (pH = 7.8) containing bovine serum albumin (BSA) by polyacrylamide resins, with pendants consisting of the oligopeptides (Arg)5(Ala)3-, (Arg)2(Ala)3-, (Lys)5(Ala)3-, His(Arg)2(Ala)3-, has been studied at 0 degrees C under N2. The ability of the oligopeptide-resins to retain adsorbed bilirubin in the presence of BSA follows the order (Arg)5(Ala)3- greater than (Arg)2(Ala)3- greater than (Lys)5(Ala)3- = His(Arg)2(Ala)3-resin. The (Arg)5(Ala)3-resin is able to abstract the second bilirubin on the albumin assuming that BSA binds two bilirubin molecules strongly.