Alpine Skiing With total knee ArthroPlasty (ASWAP): symmetric loading during skiing.

The aim of this pilot study was to determine the pressure distribution, symmetry of load between operated (OP) and non-operated (NOP) leg, and pain level during alpine skiing in participants with unilateral total knee arthroplasty (TKA). The responses of the dependent variables were analyzed following a 10-week guided skiing intervention of 2-3 days of skiing per week. Ground reaction force (GRF) was recorded bilaterally and was determined for 13 participants with TKA (65 ± 4 years) at pre- and post-test. Additionally, pain perception was determined using a numeric rating scale in the OP leg at both test sessions and after each skiing day. No statistical differences were observed between OP and NOP legs for peak and average GRF as well as the asymmetry indices at pre-test. Pain perception was low and was not increased as a consequence of the skiing intervention. In conclusion, alpine skiing did not lead to increased or decreased loading of the OP leg compared with the NOP leg. Therefore, alpine skiing may be allowed for patients with skiing experience and a good clinical outcome.

Adjustments of muscle capillarity but not mitochondrial protein with skiing in the elderly.

Downhill skiing in the elderly increases maximal oxygen uptake (VO2max) and carbohydrate handling, and produces muscle hypertrophy. We hypothesized that adjustments of the cellular components of aerobic glucose combustion in knee extensor muscle, and cardiovascular adjustments, would increase in proportion to VO2max. Nineteen healthy elderly subjects (age 67.5 ± 2.9 years) who completed 28.5 days of guided downhill skiing over 3 months were assessed for anthropometric variables, cardiovascular parameters (heart rate, hematocrit), VO2max, and compared with controls (n = 20). Biopsies of vastus lateralis muscle were analyzed for capillary density and expression of respiratory chain markers (NDUFA9, SDHA, UQCRC1, ATP5A1) and the glucose transporter GLUT4. Statistical significance was assessed with a repeated analysis of variance and Fisher's post-hoc test at a P value of 5%. VO2max increased selectively with ski training (+7 ± 2%). Capillary density (+11 ± 5%) and capillary-to-fiber ratio (12 ± 5%), but not the concentration of metabolic proteins, in vastus lateralis were increased after skiing. Cardiovascular parameters did not change. Fold changes in VO2max and capillary-to-fiber ratio were correlated and were under genetic control by polymorphisms of the regulator of vascular tone, angiotensin converting enzyme. The observations indicate that increased VO2max after recreational downhill ski training is associated with improved capillarity in a mainly recruited muscle group.

Alpine Skiing With total knee ArthroPlasty (ASWAP): metabolism, inflammation, and skeletal muscle fiber characteristics.

We investigated the effect of alpine skiing for 12 weeks on skeletal muscle characteristics and biomarkers of glucose homeostasis and cardiovascular risk factors. Twenty-three patients with a total knee arthroplasty (TKA) were studied 2.9 ± 0.9 years (mean ± SD) after the operation. Fourteen patients participated in the intervention group (IG) and nine in the control group (CG). Blood samples and muscle biopsies were obtained before (PRE) and 7.3 ± 0.8 days after (POST) the intervention, and blood samples again after a retention (RET) phase of 8 weeks. With skiing, glucose homeostasis improved in IG (decrease in fasting insulin, increase in muscle glycogen) but not in CG. Fiber type distribution and size, as well as capillary density and number of capillaries around the fibers (CAF), were not different between the operated and the non-operated leg in either group. The relative number of type I fibers increased with skiing in IG with no change in CG. Inflammatory biomarkers, plasma lipids, and mitochondrial proteins and activity did not change. Alpine skiing is metabolically beneficial and can be used as a training modality by elderly people with TKA.

Relationships between biomechanics and physiology in older, recreational alpine skiers.

The aims of this applied field study were (1) to provide descriptive data on the biomechanical variables of parallel ski steering, carving in long radii and individual technique skiing modes of older recreational skiers and (2) to determine the relationships between biomechanical and physiological variables during these skiing modes. The mean knee angle (MKA), range of knee angle (RKA), ground reaction forces (GRF), co-loading of the inner leg, mean heart rate (HR(ave)), blood lactate (LA) and mean arterial pressure were determined for 14 older skiers (61.1 ± 5.4 years). The mean GRF did not differ between the skiing modes. Parallel ski steering resulted in a greater MKA, lower RKA and lower peak GRF compared with carving in long radii and individual technique. LA correlated positively to RKA during carving in long radii and individual technique, while HR(ave) correlated negatively to MKA during parallel ski steering and carving in long radii. No significant relationships were found between the physiological and kinetic variables. In conclusion, dynamic skiing styles may result in increased muscle fiber recruitments, hence greater LA levels. Along with potentially greater loading of knee extensor muscles, lower MKAs may reduce perfusion and hinder substrate metabolism, consequently making ski turning more strenuous. Skiing with less knee flexion and a reduced RKAs could be recommended for older recreational skiers.

Salzburg Skiing for the Elderly Study: study design and intervention--health benefit of alpine skiing for elderly.

The aim of this study was to monitor the long-term effects of skiing on the health-related parameters of older individuals. This paper describes the overall study design and the intervention phase. The study utilized a randomized control group design consisting of an intervention group (n=27; age: 67.5 ± 2.8 years) and a control group (n=20; age: 67.3 ± 4.4 years). Parameters of interest were measured during pre-, post- and retention-test sessions. The intervention phase lasted for 12 weeks, with an average of 28.5 days of guided skiing. Daily heart rate (HR) profiles and global positioning system data throughout the ski day were recorded. Perceived exertion levels as well as mood status of the subjects were recorded regularly. The intervention group completed an average of 4885 vertical meters of downhill skiing, with a total skiing distance of 40.5 km/day. In the skiing phase, the average physiological load was 72.4 ± 8.9% of HR(max) . The dimension "positive mood" referred to skiing (on scale of 0-10), with an average value of 7.6 ± 1.7 after skiing. The dimension of "negative mood" was much less pronounced, having a mean of 1.1 ± 1.5 after skiing. Two subjects suffered injuries while falling during skiing. The effects of the 12-week skiing intervention on the tested parameters will be reported in the following papers of this supplementum.

Salzburg Skiing for the Elderly Study: influence of alpine skiing on aerobic capacity, strength, power, and balance.

Alpine skiing is a recreational sport with high demands on the cardiovascular and neuromuscular systems. It is assumed that skiing could have positive effects on the decline in aerobic capacity, strength, and balance ability of older individuals. In a 12-week intervention study, 47 elderly subjects (age 60-76 years) were randomized into an intervention group (IG) and a control group (CG). The IG averaged 28.5 days of guided skiing during 12 weeks. Aerobic capacity, leg power, and strength as well as postural stability were tested before, immediately after, and 10 weeks after the intervention phase. VO(2 max) improved by 7.2% from Pre to Post for the IG, without any change in the CG. Jump height increased on average by 6% over the 12 weeks for the IG, while jump height for the CG deteriorated by -11.7%. Dynamic maximal strength measured in both legs increased by 16% in the IG during the 12 weeks of skiing. In the CG, it increased by 7%, without being significant. In postural ability, no differences between groups or over time were noted. It appears that, in older individuals, 12 weeks of skiing leads to a significant increase in aerobic capacity, leg muscle power, and strength.

Impact of skier actions on the gliding times in alpine skiing.

Alpine ski races are typically won by fractions of a second. It is therefore essential for ski racers to minimize air drag as well as ski-snow friction. In contrast to air drag, ski-snow friction during actual skiing has rarely been investigated so far. Two tasks, forward/backward leaning and edging of the skis, were selected, which (a) were expected to have an impact on ski-snow friction, and (b) could be executed while gliding in tucked position. Two hypotheses were tested: (H1) Run times are affected by forward or backward leaning. (H2) Run times are affected by edging of the skis. Four professional ski testers were recruited, who conducted a total of 68 runs of straight gliding. Execution of the tasks was documented by video recordings and by measuring the force application point on the skis of one tester. The findings of this study support (H2) but not (H1). There are indications that the increased run times for edging are caused by increased ski-snow friction. From a performance point of view, it seems beneficial for ski racers to minimize edging in the gliding sections of a race.

High island densities in pulsed laser deposition: causes and implications.

By studying metal growth on Pt(111), we determine the reasons for the high island densities observed in pulsed laser deposition (PLD) compared to conventional thermal deposition. For homoepitaxy by PLD with moderate energies ( < or approximately 100 eV) of the deposited ions, high island densities are caused by the high instantaneous flux of arriving particles. Additional nuclei are formed at high ion energies (> or approximately 200 eV) by adatoms created by the impinging ions. For heteroepitaxy, the island density is also increased by intermixing (deposited material implanted in the surface), creating an inhomogeneous potential energy surface for diffusing atoms. We discuss implications for layer-by-layer growth and sputter deposition.

Tissue culture and transient transformation of Marestail (Conyza canadensis (L.) Cronquist).

Glyphosate resistant crops are useful to agriculture by facilitating the use of nonselective herbicides, such as RoundUp, that have low human and environmental toxicity. The occurrence of glyphosate resistant weeds, however, has raised concern about the future utility of these crops. Conyza canadensis (L.) Cronquist (marestail or horseweed) is one such glyphosate resistant weed that has yet to be fully analyzed or established in tissue culture. Tissue culture enables the examination of physiological characteristics of a plant in an aseptic and controlled environment. For the present study, mairstail was cultured on a Murashige and Skoog based medium supplemented with 6-benzylaminopurine, and alpha-naphthaleneacetic acid. Plant regeneration was achieved on the same basal medium supplemented with only gibberellic acid. Glyphosate resistance could be demonstrated in the cultured tissues. The cultures could also be transformed with Agrobacterium tumefaciens without chemically inducing virulence using phenolics or glucose and resulting in a transformation frequency (transgenic events per total number of explants used) of about 13%. The tissue culture growth, preliminary glyphosate resistance data and genetic transformation data gathered in this project provide the means to further evaluate the mode of glyphosate resistance expressed by marestail.

Conformational analysis of atropine.

The conformation of atropine was studied by nmr and dipole moment measurements. It was shown that there is a cis conformation between the C = O bond in the ester group and the tropanyl group. The nmr measurements indicated that the Ph--CH(CH2OH)--CO-- grouping assumes conformations I and II in equilibrium, while the conformational isomer III can be excluded. Consequently, the distance between the nitrogen atom and the carbonyl group is 4.5--5.0 A, and this determines the binding to the cholinergic receptor. This distance is substantially less than the 7 A presumed by other authors earlier.

[Microbial invasion of the intestine in colonising agamas (Agama agama) from the aspect of hygienic water control in tropical areas of West Africa (author's transl)]. / Zur Frage der mikrobiellen Darmbesiedlung der Siedleragamen (Agama agama) unter dem Aspekt der hygienischen Wasserkontrolle in tropischen Gebieten Westafrikas

Agamae are regularly found in great numbers in the neighbourhood of water supply plants and excrements of these animals can be traced to the plants proper. In order to ascertain the cause of drinking water infections, 37 Agamae were cought, immediately killed and the bowel contents examined. It was found that the Agamae have no uniform microbial population and that none of the aerobically cultivated bacterial species is present in all animals (Tablet 1 indicates the species for each animal). With regard to the hygienic inspection of drinking water it is important to know that only some of the Agamae discharge E. coli or coliform bacteria with the excrements and that 7 out of 12 animals which excrete large quantities of salmonellae were not found to harbour E. coli or coliform bacteria in their bowels. Under these circumstances the prerequisite to be met by the indicator function for E. coli and coliform bacteria no longer exists for water infections brought about by reptile excrements. The detection of salmonellae in water must be given priority over the detection of E. coli and coliform bacteria if - as happens in West Africa - the spread of salmonellae by reptiles or other animals, which do not excrete E. coli or coliform bacteria regularly, must be considered.

[Investigation on the presence of salmonella in drinking water from water supplies and distribution systems in Togo (author's transl)]. / Untersuchungen über das Vorkommen von Salmonellen im Trinkwasser togoischer Wasserversorgungsanlagen.

Bacteriological drinking water examination of samples from water works and wells as well as from their distribution systems revealed that from 26 samples, where Salmonella organisms could be isolated, in 16 cases E. coli- and coliforms could not be found and that in 9 of these cases even the colony count was below 100 colonies per ml at 20 degrees C and 37 degrees C incubation temperature. The common reasons for such contaminations are technical deficiencies, mostly faulty well-heads or broken covers of reservoirs. Rainbow lizzards (Agama agama), very common in these regions, can thus easily gain access to wells and reservoirs and pollute the groundwater. Rainbow lizzards do not posses a constant and uniform microbial flora of the intestine. Among lizzards which excrete Salmonella organisms in great numbers, relatively often individuals could be found which harbour either no E. coli- and/or coliforms at all or only in very reduced numbers. In the light of these results an efficient primary protection of all water supplies by a secure covering of well-heads and reservoirs in particular seems to be of paramount importance in tropical countries. This is very much in contrast to the situation most commonly seen in these areas. The necessary measures would have to be accompanied and supplemented by alterations of the installations in the house where the creation of open reservoirs must be avoided.

Bancroftian Filariasis in Togo 1. a comparative field study of the membrane filtration concentration technique and conventional blood films.

The membrane concentration filtration technique which has proved very successful in use in areas of subperiodic filariasis in the Pacific, has been used to study an area of nocturnally periodic in Togo. The results obtained were similar to those from areas of low endemicity in the Pacific. The method was easy to apply under field conditions in Africa and the taking of venous blood samples proved competely acceptable to a rural population in south-eastern Togo.

Tropine derivatives with central activities. Part II: Solvolysis of N-substituted nortropine methanesulfonates.

The preparation and the reaction kinetical properties in solvolysis of a series of N-substituted nortropine methanesulfonates 1-8 are described. It was found that the rate of solvolysis depends on the nature of the N-substituents considerably. The solvolysis rates can be brought into correlation with the electron donating and withdrawing and steric properties of the N-substituents. Methane-sulfonates of other two bicyclic aminoalcohols 10, 11 were also prepared and kinetically studied.

[Synthesis and pharmacology of N-stereoisomers of quaternary tropane compounds]. / Synthese und Pharmakologie von N-stereoisomeren quartären Tropan-Verbindungen.

The synthesis of (8r)-8-(4-biphenylmethyl)-atropinium bromide (3) as N-isomeric form of xenytropium bromide, (8s)-8-(4-biphenylmethyl)-atropinium bromide (2), is reported. It was revealed, that the equatorial alkylation predominates in quaternization of tertiary tropane compounds. Furthermore, the preparation of other N-isomeric pairs of quaternary tropane derivatives in pure form is described. Xenytropium bromide is more active--16 times on the parasympathic endplate and 8 times on the ganglion--than its N-isomer.

A new technique for the determination of microfilarial densities in onchocerciasis.

Precise measurement of the parasite load in helminthic infections makes it possible to correlate morbidity, the individual response to treatment, and the best control methods. A membrane filtration technique was recently developed for quantifying Wuchereria bancrofti microfilaraemia. The present paper describes its application to onchocerciasis in a study on 107 patients in northern Togo. The technique is cheap and simple to apply under field conditions, and is extremely efficient at recovering microfilariae from skin snips.

Epidemiological studies on onchocerciasis by means of a new field technique.

A new membrane filter concentration technique for the detection and quantification of Onchocerca volvulus microfilariae in skin snips was compared for sensitivity and efficiency with a widely used "standard" technique. A field study was carried out in five villages in an onchocerciasis focus north-east of the town of Sokodé, Mô river valley, Togo. Use of the new technique resulted in a substantial rise in the observed prevalence and density of microfilariae.