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1.	Ponsot, Elodie, 1973-, et al. (author) Skeletal muscle telomere length is not impaired in healthy physically active old women and men 2008 In: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 37:4, s. 467-472 Journal article (peer-reviewed)abstract We have previously shown that the number of satellite cells is lower in old than young men and women. The aim of this study was to further explore the effects of aging on the regenerative potential of skeletal muscle in 16 young and 26 old men and women with comparable physical activity level (young, 25 +/- 4 years; old, 75 +/- 4 years). Mean and minimum telomere lengths were determined using Southern blot analyses on biopsies obtained from the tibialis anterior muscle. There were no significant age or gender effects on mean and minimal telomeric lengths, suggesting that the replicative potential in the remaining satellite cells in the tibialis anterior muscle is not impaired with increasing age and the existence of in vivo regulatory mechanisms allowing the maintenance of telomere length. These results imply that moderate physical activity regularly performed by old subjects is not associated with accelerated telomere loss.
2.	Mamontov, Eugen, 1955, et al. (author) Mathematical models and numerical simulation results for oncogeny: Specific problems and different tools for various user communities 2008 In: Abstracts Booklet. CancerSim2008 — Euroconference on Modelling and Simulation of Cancer Growth and Therapy, 19-21 May, Turin, Italy; N. Bellomo and G. Forni (Chairmen) http://www.cancersim2008.org. Conference paper (peer-reviewed)
3.	Kadi, Fawzi, et al. (author) The behaviour of satellite cells in response to exercise : what have we learned from human studies? 2005 In: Pflügers Archiv. - : Springer Science and Business Media LLC. - 0031-6768 .- 1432-2013. ; 451:2, s. 319-327 Journal article (other academic/artistic)abstract Understanding the complex role played by satellite cells in the adaptive response to exercise in human skeletal muscle has just begun. The development of reliable markers for the identification of satellite cell status (quiescence/activation/proliferation) is an important step towards the understanding of satellite cell behaviour in exercised human muscles. It is hypothesised currently that exercise in humans can induce (1) the activation of satellite cells without proliferation, (2) proliferation and withdrawal from differentiation, (3) proliferation and differentiation to provide myonuclei and (4) proliferation and differentiation to generate new muscle fibres or to repair segmental fibre injuries. In humans, the satellite cell pool can increase as early as 4 days following a single bout of exercise and is maintained at higher level following several weeks of training. Cessation of training is associated with a gradual reduction of the previously enhanced satellite cell pool. In the elderly, training counteracts the normal decline in satellite cell number seen with ageing. When the transcriptional activity of existing myonuclei reaches its maximum, daughter cells generated by satellite cell proliferation are involved in protein synthesis by enhancing the number of nuclear domains. Clearly, delineating the events and the mechanisms behind the activation of satellite cells both under physiological and pathological conditions in human skeletal muscles remains an important challenge.
4.	Ruiz, Jonatan R., et al. (author) Homocysteine levels in children and adolescents are associated with the methylenetetrahydrofolate reductase 677C>T genotype, but not with physical activity, fitness or fatness : the European Youth Heart Study 2007 In: British Journal of Nutrition. - Cambridge : Cambridge university press. - 0007-1145 .- 1475-2662. ; 97:2, s. 255-262 Journal article (peer-reviewed)abstract To examine the associations of total plasma homocysteine (tHcy) with physical activity, cardiorespiratory fitness and fatness in children and adolescents, a cross-sectional study of 301 children (9–10 years old) and 379 adolescents (15–16 years old) was conducted. Physical activity was measured by accelerometry. Cardiorespiratory fitness was measured with a maximal ergometer bike test. Body fat was derived from the sum of five skinfold thicknesses. Genotyping for the methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism was done by DNA sequencing. Fasting tHcy level was the outcome variable. Multiple regressions were used to determine the degree to which variance in tHcy was explained by physical activity, cardiorespiratory fitness and body fat, after controlling for potential confounders including MTHFR 677C>T genotype. tHcy levels were neither associated with any measure of level and pattern of physical activity nor with data on cardiorespiratory fitness, or body fat, in any age group after controlling for potential confounders including MTHFR 677C>T and even when subgroups 677TT and 677CC+CT were analysed separately. Mean values of tHcy were significantly higher in the TT subgroup compared with CC and CT subgroups in children (TT 7·4 μmol/l, CC 6·3 μmol/l, CT 6·6 μmol/l, P < 0·001 and P = 0·019, respectively) and adolescents (TT 16·9 μmol/l, CC 8·3 μmol/l, CT 9·0 μmol/l, both P < 0·001). The results suggest that physical activity, fitness and body fat are not associated with tHcy levels in children and adolescents, even after controlling for presence of the MTHFR 677C>T genotype, the main influence on tHcy levels in these subjects.
5.	Marklund, P, et al. (author) Unity and diversity of tonic and phasic executive control components in episodic and working memory. 2007 In: Neuroimage. - : Elsevier. - 1053-8119 .- 1095-9572. ; 36:4, s. 1361-73 Journal article (peer-reviewed)
6.	Jörntell, Henrik, et al. (author) Reciprocal bidirectional plasticity of parallel fiber receptive fields in cerebellar Purkinje cells and their afferent interneurons. 2002 In: Neuron. - 0896-6273. ; 34:5, s. 797-806 Journal article (peer-reviewed)abstract The highly specific relationships between parallel fiber (PF) and climbing fiber (CF) receptive fields in Purkinje cells and interneurons suggest that normal PF receptive fields are established by CF-specific plasticity. To test this idea, we used PF stimulation that was either paired or unpaired with CF activity. Conspicuously, unpaired PF stimulation that induced long-lasting, very large increases in the receptive field sizes of Purkinje cells induced long-lasting decreases in receptive field sizes of their afferent interneurons. In contrast, PF stimulation paired with CF activity that induced long-lasting decreases in the receptive fields of Purkinje cells induced long-lasting, large increases in the receptive fields of interneurons. These properties, and the fact the mossy fiber receptive fields were unchanged, suggest that the receptive field changes were due to bidirectional PF synaptic plasticity in Purkinje cells and interneurons.
7.	Kadi, Fawzi, et al. (author) The effects of regular strength training on telomere length in human skeletal muscle 2008 In: Medicine & Science in Sports & Exercise. - : Lippincott Williams & Wilkins. - 0195-9131 .- 1530-0315. ; 40:1, s. 82-87 Journal article (peer-reviewed)abstract PURPOSE: The length of DNA telomeres is an important parameter of the proliferative potential of tissues. A recent study has reported abnormally short telomeres in skeletal muscle of athletes with exercise-associated fatigue. This important report raises the question of whether long-term practice of sports might have deleterious effects on muscle telomeres. Therefore, we aimed to compare telomere length of a group of power lifters (PL; N = 7) who trained for 8 +/- 3 yr against that of a group of healthy, active subjects (C; N = 7) with no history of strength training. METHODS: Muscle biopsies were taken from the vastus lateralis, and the mean and minimum telomeric restriction fragments (TRF) (telomere length) were determined, using the Southern blot protocol previously used for the analysis of skeletal muscle. RESULTS: There was no abnormal shortening of telomeres in PL. On the contrary, the mean (P = 0.07) and the minimum (P = 0.09) TRF lengths in PL tended to be higher than in C. In PL, the minimum TRF length was inversely correlated to the individual records in squat (r = -0.86; P = 0.01) and deadlift (r = -0.88; P = 0.01). CONCLUSION: These results show for the first time that long-term training is not associated with an abnormal shortening of skeletal muscle telomere length. Although the minimum telomere length in PL remains within normal physiological ranges, a heavier load put on the muscles means a shorter minimum TRF length in skeletal muscle.
8.	Kadi, Fawzi, et al. (author) The number of satellite cells in slow and fast fibres from human vastus lateralis muscle 2006 In: Histochemistry and Cell Biology. - : Springer Science and Business Media LLC. - 0948-6143 .- 1432-119X. ; 126:1, s. 83-87 Journal article (peer-reviewed)abstract The aim of this investigation was to study the distribution of satellite cells in slow (type I fibres) and fast (type II fibres) fibres from human vastus lateralis muscle. This muscle is characterised by a mixed fibre type composition and is considered as the site of choice for biopsies in research work and for clinical diagnosis. Biopsy samples were obtained from five healthy young volunteers and a total of 1,747 type I fibres and 1,760 type II fibres were assessed. Satellite cells and fibre type composition were studied on serial muscle cross-sections stained with specific monoclonal antibodies. From a total of 218 satellite cells, 116 satellite cells were found in contact with type I fibres (53.6+/-8% of the satellite cells associated to type I fibres) and 102 satellite cells in contact with type II fibres (46.4+/-8% of the satellite cells associated to type II fibres). There was no significant difference (P=0.4) between the percentages of satellite cells in contact with type I and with type II fibres. Additionally, there was no relationship between the mean number of satellite cells per fibre and the mean cross-sectional area of muscle fibres. In conclusion, our results show that there is no fibre type-specific distribution of satellite cells in a human skeletal muscle with mixed fibre type composition.
9.	Pontén, Eva, et al. (author) Higher amount of MyHC IIX in a wrist flexor in tetraplegic compared to hemiplegic cerebral palsy 2008 In: Journal of the Neurological Sciences. - : Elsevier. - 0022-510X .- 1878-5883. ; 266:1-2, s. 51-56 Journal article (other academic/artistic)abstract Spastic cerebral palsy can be divided into diagnostic groups by the relative severity of the arm impairment. This study investigates if hemiplegic, tetraplegic or diplegic cerebral palsy (CP) results in different patterns of myosin heavy chain (MyHC) expression in the flexor carpi ulnaris muscle from 17 young patients with CP. Using enzyme-immunohistochemistry and gel electrophoresis techniques we found a higher percentage of fibers expressing fast MyHC IIx (52%) in tetraplegic CP compared to hemiplegic patients (32%), (p < 0.05). Tetraplegic CP also resulted in a lower amount of fibers expressing slow MyHC I (18%) compared to hemiplegic CP (40%), (p < 0.005). The proportion of muscle fibers containing fetal MyHC was higher in tetraplegic CP compared to other groups, (p < 0.005). Taken together theses results indicate that tetraplegic CP is associated with a shift from slow to fast myosins and that regenerative events are more prominent in tetraplegic CP compared with milder brain damage.
10.	Verney, Julien, et al. (author) Combined lower body endurance and upper body resistance training improves performance and health parameters in healthy active elderly 2006 In: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 97:3, s. 288-297 Journal article (other academic/artistic)abstract We investigated the effects of combined lower body (LB) endurance and upper body (UB) resistance training on endurance, strength, blood lipid profile and body composition in active older men. Ten healthy still active men (73+/-4 years, V(O2) peak: 36 (31-41) ml min-1 kg-1) were tested before and after 14 weeks of combined training (3 times week-1). Training consisted of 3x12 min of high intensity interval training on a bicycle for endurance interspersed by 3x12 min of UB resistance exercises. V(O2) peak during leg cycling and arm cranking, isokinetic torque of knee extensor and shoulder abductor and the cross-sectional area (CSA) of several muscles from UB and LB were measured. Sagittal abdominal diameter (SAD) and abdominal fat area were measured on MRI scans. Total body composition was assessed by hydrostatic weighing (HW) and dual-energy X-ray absorptiometry (DEXA). Blood lipid profile was assessed before and after training. By the end of the training period, V(O2) peak (l min-1) increased significantly by 9 and 16% in leg cycling and arm cranking tests, respectively. Maximal isokinetic torque increased both for the knee extensor and shoulder abductor muscle groups. CSA increased significantly in deltoid muscle. Percentage of body fat decreased by 1.3% (P<0.05) and abdominal fat and SAD decreased by 12 and 6%, respectively (P<0.01). There was also a significant decrease in total cholesterol and low-density lipoprotein. Thus, combined LB endurance and UB resistance training can improve endurance, strength, body composition and blood lipid profile even in healthy active elderly.
11.	Kadi, Fawzi, 1970- (author) In response to Point: Counterpoint : "Satellite cell addition is/is not obligatory for skeletal muscle hypertrophy" 2007 In: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 103:3, s. 1105-1105 Journal article (other academic/artistic)abstract In this letter, the point: counterpoint issue (1, 5) is addressed solely by referring to studies in humans. The analysis of histological sections from skeletal muscle of power lifters with many years of practice leaves no doubt about the role of satellite cells as myonuclei donors in the hypertrophied muscle fibre. The larger the cross-sectional area of fibres, the higher the number of myonuclei per cross-section (2, 4). Importantly, the strong relationship between the cross-sectional area of fibres and the number of myonuclei (r = 0,86; p < 0.0001) is obtained with a range of areas between 2500 µm2 and 14000 µm2 (4). Existing myonuclei are able to sustain an initial hypertrophy of the muscle fibre as long as the transcriptional activity of existing myonuclei does not reach its maximum (2, 3, 5). Satellite cells become myonuclei donors when fibre size reaches the ceiling size (2, 3, 5). Additionally, we should not forget that satellite cells are also donors of myonuclei to newly generated myotubes (2, 4). The intensity of exercise and the initial fibre area of the subjects included in a training program are important factors governing whether daughter cells generated by satellite cell activation and proliferation provide new myonuclei to existing myofibres or to newly generated myotubes. Finally, in parallel with these events, some of the daughter cells can escape differentiation and facilitate renewal of the satellite cell pool. Efforts should be made to better understand key elements guiding the fate of satellite cells.
12.	Larsson, Britt, et al. (author) Blood supply and oxidative metabolism in muscle biopsies of female cleaners with and without myalgia 2004 In: The Clinical Journal of Pain. - : Ovid Technologies (Wolters Kluwer Health). - 0749-8047 .- 1536-5409. ; 20:6, s. 440-446 Journal article (peer-reviewed)abstract OBJECTIVES: Pathomechanisms of work-related myalgia are poorly understood. Myalgia is thought to be caused by excitation of nociceptors present in the muscular tissue but not in the muscle fiber itself. Muscle contraction in combination with hypoxia is known to excite nociceptors. Morphologic analysis can contribute to the knowledge of the excitation of nociceptors. This study thoroughly examines the morphology of the trapezius muscle's capillary supply and signs of disturbed oxidative metabolism to understand their role in work-related myalgia. METHODS: Surgical trapezius muscle biopsies were obtained from 25 female cleaners with long-standing work-related myalgia, 25 female cleaners without trapezius myalgia, and 21 healthy teachers. Enzyme and immunohistochemical stainings were performed to highlight fibers with aberrant intermyofibrillar patterns, indicating a disturbed oxidative metabolism (also known as moth-eaten fibers) and a disturbed capillary supply of different fibers. RESULTS: A significantly lower number of capillaries per fiber area in cleaners suffering from myalgia compared with cleaners without trapezius myalgia was found. Moth-eaten fibers were found in the 3 groups, but these fibers were significantly more prevalent in the groups of cleaners than in the healthy teacher group. CONCLUSION: This work indicates that the capillary supply of trapezius is affected in work-related trapezius myalgia. More studies are needed to understand possible mechanisms that would explain the occurrence of moth-eaten fibers.
13.	Paulsen, Gøran, et al. (author) Maximal eccentric exercise induces a rapid accumulation of small heat shock proteins on myofibrils and a delayed HSP70 response in humans 2007 In: American Journal of Physiology. Regulatory Integrative and Comparative Physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 293:2, s. R844-R853 Journal article (peer-reviewed)abstract In this study the stress protein response to unaccustomed maximal eccentric exercise in humans was investigated. Eleven healthy males performed 300 maximal eccentric actions with the quadriceps muscle. Biopsies from vastus lateralis were collected at 30 min and 4, 8, 24, 96, and 168 h after exercise. Cellular regulation and localization of heat shock protein (HSP) 27, alpha B-crystallin, and HSP70 were analyzed by immunohistochemistry, ELISA technique, and Western blotting. Additionally, mRNA levels of HSP27, alpha B-crystallin, and HSP70 were quantified by Northern blotting. After exercise (30 min), 81 +/- 8% of the myofibers showed strong HSP27 staining (P < 0.01) that gradually decreased during the following week. alpha B-Crystallin mimicked the changes observed in HSP27. After exercise (30 min), the ELISA analysis showed a 49 +/- 13% reduction of the HSP27 level in the cytosolic fraction (P < 0.01), whereas Western blotting revealed a 15-fold increase of the HSP27 level in the myofibrillar fraction (P < 0.01). The cytosolic HSP70 level increased to 203 +/- 37% of the control level 24 h after exercise (P < 0.05). After 4 days, myofibrillar-bound HSP70 had increased approximately 10-fold (P < 0.01) and was accompanied by strong staining on cross sections. mRNA levels of HSP27, alpha B-crystallin, and HSP70 were all elevated the first day after exercise (P < 0.01); HSP70 mRNA showed the largest increase (20-fold at 8 h). HSP27 and alpha B-crystallin seemed to respond immediately to maximal eccentric exercise by binding to cytoskeletal/myofibrillar proteins, probably to function as stabilizers of disrupted myofibrillar structures. Later, mRNA and total HSP protein levels, especially HSP70, increased, indicating that HSPs play a role in skeletal muscle recovery and remodeling/adaptation processes to high-force exercise
14.	Kadi, Fawzi, et al. (author) Satellite cells and myonuclei in young and elderly women and men 2004 In: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 29:1, s. 120-127 Journal article (peer-reviewed)abstract The overall aim of this study was to assess the effects of aging on the satellite cell population. Muscle biopsies were taken from the tibialis anterior muscle of healthy, moderately active young (age range, 20-32 years; n = 31) and elderly (age range, 70-83 years; n = 27) women and men with comparable physical activity pattern. Satellite cells and myonuclei were visualized using a monoclonal antibody against neural cell adhesion molecule and counterstained with Mayer's hematoxylin. An average of 211 (range, 192-241) muscle fibers were examined for each individual. Compared with the young women and men, the elderly subjects had a significantly lower (P < 0.011) number of satellite cells per muscle fiber but a significantly higher (P < 0.004) number of myonuclei per muscle fiber. The number of satellite cells relative to the total number of nuclei [satellite cells/(myonuclei + satellite cells)] was significantly lower in the elderly than in the young women and men. These results imply that a reduction in the satellite cell population occurs as a result of increasing age in healthy men and women.
15.	Mamontov, Eugen, 1955 (author) Homeorhesis and evolutionary properties of living systems: From ordinary differential equations to the active-particle generalized kinetics theory 2006 In: 10th Evolutionary Biology Meeting at Marseilles, 20-22 September 2006, Marseilles, France. Conference paper (peer-reviewed)abstract Advanced generalized-kinetic-theory (GKT) models for biological systems are developed for populations of active (or living) particles [1]-[5]. These particles are described with both the stochastic variables common in kinetic theory (such as time, the particle random location and velocity) and the stochastic variables related to the internal states of an active particle. Evolution of these states represents biological, ecological, or social properties of the particle behavior. Paper [6] analyzes a number of the well-known statistical-mechanics approaches and shows that the active-particle GKT (APGKT) is the only treatment capable of modelling living systems. Work [2] summarizes the significance of the notion of an active particle in kinetic models. This notion draws attention to the features distinguishing living matter from nonliving matter. They are discussed by many authors (e.g., [7]-[15], [1]-[3], [6], [16]-[18]). Work [11] considers a lot of differences between living and nonliving matters, and the limitations of the modelling approaches developed for nonliving matter. Work [6] mainly focuses on the comparison of a few theoretical mechanics treatments in terms of the key living-matter properties formulated in [15]. One of the necessary properties of the evolution of living systems is homeorhesis. It is, loosely speaking, a peculiar qualitative and quantitative insensitivity of a living system to the exogenous signals acting on it. The earlier notion, homeostasis, was introduced by W. B. Cannon in 1926 who discussed the phenomenon in detail later [7]. Homeorhesis introduced by C. H. Waddington [8, p. 32] generalizes homeostasis and is well known in biology [8], [9], [12]. It is an inherent part of mathematical models for oncogeny (e.g., [16]-[18], [6, Appendix]). Homeorhesis is also discussed in [3, Section 4] in connection with APGKT. Homeorhesis is documented in ecology (e.g., [11], [13, the left column on p. 675]) where it is one of the key notions of the strong Gaia theory, a version of the Gaia theory (e.g., [14, Chapter 8]). The strong Gaia theory “states that the planet with its life, a single living system, is regulated in certain aspects by that life” [14, p. 124]. The very origin of the name “Gaia” is related to homeorhesis or homeostasis [14, p. 118]. These notions are also used in psychology and sociology. If evolution of a system is not homeorhetic, the system can not be living. Work [6, Appendix] derives a preliminary mathematical formulation of homeorhesis in terms of the simplest dynamical systems, i.e. ordinary differential equations (ODEs). The present work complements, extended, and further specify the approach of [6, Appendix]. The work comprises the two main parts. The first part develops the sufficient conditions for ODE systems to describe homeorhesis, and suggests a fairly general structure of the ODE model. It regards homeorhesis as piecewise homeostasis. The model can be specified in different ways depending on specific systems and specific purposes of the analysis. An example of the specification is also noted (the PhasTraM nonlinear reaction-diffusion model for hyperplastic oncogeny [16]-[18]). The second part of the work discusses implementation of the above homeorhesis ODE model in terms of a special version [3] of APGKT (see above). The key feature of this version is that the components of a living population need not be discrete: the subdivision into the components is described with a general, continuous-discrete probability distribution (see also [6]). This enables certain properties of living matter noted in [15]. Moreover, the corresponding APGKT model presents a system of, firstly, a generalized kinetic equation for the conditional distribution function conditioned by the internal states of the population and, secondly, Ito's stochastic differential equations for these states. This treatement employs the results on nonstationary invariant diffusion stochastic processes [19]. The second part of the work also stresses that APGKT is substantially more important for the living-matter analysis than in the case of nonliving matter. One of the reasons is certain limitations in experimental sampling of the living-system modes presented with stochastic processes. A few directions for future research are suggested as well. REFERENCES: [1] Bellomo, N., Bellouquid, A. and Delitala, M., 2004, Mathematical topics on the modelling complex multicellular systems and tumor immune cells competition, Math. Models Methods Appl. Sci., 14, 1683-1733. [2] Bellomo, N., 2006, New hot Paper Comments, Essential Science Indicators, http://www.esi-topics.com/nhp/2006 /may- 06-NicolaBellomo.html. [3] Willander, M., Mamontov, E. and Chiragwandi, Z., 2004, Modelling living fluids with the subdivision into the components in terms of probability distributions, Math. Models Methods Appl. Sci. 14, 1495-1520. [4] Bellomo, N. and Maini, P.K., 2005, Preface and the Special Issue “Multiscale Cancer Modelling-A New Frontier in Applied Mathematics”, Math. Models Methods Appl. Sci., 15, iii-viii. [5] De Angelis, E. and Delitala, M., 2006, Modelling complex systems in applied sciences: Methods and tools of the mathematical kinetic theory for active particles. Mathl Comput. Modelling, 43, 1310-1328. [6] Mamontov, E., Psiuk-Maksymowicz, K. and Koptioug, A., 2006, Stochastic mechanics in the context of the properties of living systems, Mathl Comput. Modelling, Article in Press, 13 pp. [7] Cannon, W.B., 1932, The Wisdom of the Body (New York: Norton). [8] Waddington, C.H., 1957, The Strategy of the Genes. A Discussion of Some Aspects of Theoretical Biology (London, George Allen and Unwin). [9] Waddington, C.H., 1968, Towards a theoretical biology, Nature, 218, 525-527. [10] Cotnoir, P.-A., 1981, La compétence environnementale: Une affaire d’adaptation. Séminaire en écologie behaviorale, Univeristé du Québec, Montralé. Available online at: http://pac.cam.org/culture.doc . [11] O’Neill, R.V., DeAngelis, D.L., Waide, J.B. and Allen, T.F.H., 1986, A Hierarchical Concept of Ecosystems, Princeton: Princeton Univ. Press). [12] Sauvant, D., 1992, La modélisation systémique en nutrition, Reprod. Nutr. Dev., 32, 217-230. [13] Christensen, N.L., Bartuska, A.M., Brown, J.H., Carpenter, S., D'Antonio, C., Francis, R., Franklin, J.F., MacMahon, J.A., Noss, R.F., Parsons, D.J., Peterson, C.H., Turner, M.G. and Woodmansee, R.G., 1996, The Report of the Ecological Society of America Committee on the Scientific Basis for Ecosystem Management, Ecological Applications, 6, 665-691. Available online at: http://www.esa.org/pao/esaPositions/Papers/ReportOfSBEM.php. [14] Margulis, L., 1998, Symbiotic Planet. A New Look at Evolution (Amherst: Sciencewriters). [15] Hartwell, L.H., Hopfield, J.J., Leibler, S. and Murray, A.W., 1999, From molecular to modular cell biology, Nature, 402, C47-C52. [16] Mamontov, E., Koptioug, A.V. and Psiuk-Maksymowicz, K., 2006, The minimal, phase-transition model for the cell- number maintenance by the hyperplasia-extended homeorhesis, Acta Biotheoretica, 54, 44 pp., (no. 2, May-June, accepted). [17] Psiuk-Maksymowicz, K. and Mamontov, E., 2005, The time-slices method for rapid solving the Cauchy problem for nonlinear reaction-diffusion equations in the competition of homeorhesis with genotoxically activated hyperplasia, In: European Conference on Mathematical and Theoretical Biology - ECMTB05 (July 18-22, 2005) Book of Abstracts, Vol.1 (Dresden: Center for Information Services and High Performance Computing, Dresden Univ. Technol.), p. 429 (http://www.ecmtb05.org/). [18] Psiuk-Maksymowicz, K. and Mamontov, E., 2006, The homeorhesis-based modelling and fast numerical analysis for oncogenic hyperplasia under radiation therapy, submitted. [19] Mamontov, E., 2005, Nonstationary invariant distributions and the hydrodynamic-style generalization of the Kolmogorov-forward/Fokker-Planck equation, Appl. Math. Lett. 18 (9) 976-982.
16.	Norrman, Eva, et al. (author) Optimization of image process parameters through factorial experiments using a flat panel detector 2007 In: Physics in Medicine and Biology. - Bristol : IOP publishing. - 0031-9155 .- 1361-6560. ; 52:17, s. 5263-5276 Journal article (peer-reviewed)abstract In the optimization process of lumbar spine examinations, factorial experiments were performed addressing the question of whether the effective dose can be reduced and the image quality maintained by adjusting the image processing parameters. A 2(k)-factorial design was used which is a systematic and effective method of investigating the influence of many parameters on a result variable. Radiographic images of a Contrast Detail phantom were exposed using the default settings of the process parameters for lumbar spine examinations. The image was processed using different settings of the process parameters. The parameters studied were ROI density, gamma, detail contrast enhancement (DCE), noise compensation, unsharp masking and unsharp masking kernel (UMK). The images were computer analysed and an image quality figure (IQF) was calculated and used as a measurement of the image quality. The parameters with the largest influence on image quality were noise compensation, unsharp masking, unsharp masking kernel and detail contrast enhancement. There was an interaction between unsharp masking and kernel indicating that increasing the unsharp masking improved the image quality when combined with a large kernel size. Combined with a small kernel size however the unsharp masking had a deteriorating effect. Performing a factorial experiment gave an overview of how the image quality was influenced by image processing. By adjusting the level of noise compensation, unsharp masking and kernel, the IQF was improved to a 30% lower effective dose.
17.	Andersson, Johan, et al. (author) Effects of lung volume and involuntary breathing movements on the human diving response 1998 In: European Journal of Applied Physiology and Occupational Physiology. - : Springer Science and Business Media LLC. - 0301-5548 .- 1439-6319 .- 1439-6327. ; 77:1-2, s. 19-24 Journal article (peer-reviewed)abstract The effects of lung volume and involuntary breathing movements on the human diving response were studied in 17 breath-hold divers. Each subject performed maximal effort apnoeas and simulated dives by apnoea and cold water face immersion, at lung volumes of 60%, 85%, and 100% of prone vital capacity (VC). Time of apnoea, blood pressure, heart rate, skin capillary blood flow, and fractions of end-expiratory CO2 and O2 were measured. The length of the simulated dives was the shortest at 60% of VC, probably because at this level the build up of alveolar CO2 was fastest. Apnoeas with face immersion at 100% of VC gave a marked drop in arterial pressure during the initial 20 s, probably due to high intrathoracic pressure mechanically reducing venous return. The diving response was most pronounced at 60% of VC. We concluded that at the two larger lung volumes both mechanical factors and input from pulmonary stretch receptors influenced the bradycardia and vasoconstriction, resulting in a nonlinear relationship between the breath-hold lung volume and magnitude of the diving response in the near-VC range. Furthermore, the involuntary breathing movements that appeared during the struggle phase of the apnoeas were too small to affect the diving response.
18.	Ambrosio, Fabrisia, et al. (author) The effect of muscle loading on skeletal muscle regenerative potential : an update of current research findings relating to aging and neuromuscular pathology 2009 In: American Journal of Physical Medicine & Rehabilitation. - Baltimore : Lippincott Williams & Wilkins. - 0894-9115 .- 1537-7385. ; 88:2, s. 145-155 Research review (peer-reviewed)abstract Skeletal muscle is a dynamic tissue with a remarkable ability to continuously respond to environmental stimuli. Among its adaptive responses is the widely investigated ability of skeletal muscle to regenerate after loading or injury or both. Although significant basic science efforts have been dedicated to better understand the underlying mechanism controlling skeletal muscle regeneration, there has been relatively little impact in the clinical approaches used to treat skeletal muscle injuries and wasting. The purpose of this review article is to provide an overview of the basic biology of satellite cell function in response to muscle loading and to relate these findings in the context of aging and neuromuscular pathology for the rehabilitation medicine specialist.
19.	Eliason, Gabriella, et al. (author) Physical performance and muscular characteristics in different stages of COPD 2009 In: Scandinavian Journal of Medicine and Science in Sports. - : Wiley-Blackwell Publishing Inc.. - 0905-7188 .- 1600-0838. ; 19:6, s. 865-870 Journal article (peer-reviewed)abstract This study has examined exercise capacity and muscle morphology in patients with different severities of chronic obstructive pulmonary disease (COPD). Twenty-three patients and 12 healthy matched controls were recruited. Based on the severity of airflow obstruction, patients were divided into two subgroups. Exercise capacity was determined using a 6-min walk test. Muscle fiber composition, fiber area and number of satellite cells/muscle fiber were determined in muscle biopsies using immunohistochemistry. A progressive decline in exercise capacity was noted with ascending disease severity. Furthermore, a correlation between reduction in exercise capacity and changes in muscle fiber composition was observed in COPD. The group with severe and very severe COPD had a lower proportion of type I and a higher proportion of type IIa fibers compared with the other groups. In severe and very severe COPD, a reduction in fiber area of type IIa fibers was also seen. The number of satellite cells/muscle fiber did not differ between the groups. In conclusion, a decline in exercise capacity occurs already in mild and moderate COPD, indicating that the 6-min walk test is a reliable indicator of disease severity. Furthermore, changes in skeletal muscle morphology are associated with disease severity while muscle regenerative capacity is not altered.
20.	Mamontov, Eugen, 1955, et al. (author) The minimal, phase-transition model for the cell-number maintenance by the hyperplasia-extended homeorhesis 2006 In: Acta Biotheoretica. - : Springer Science and Business Media LLC. - 0001-5342 .- 1572-8358. ; 54:2, s. 61-101 Journal article (peer-reviewed)abstract Oncogenic hyperplasia is the first and inevitable stage of formation of a (solid) tumor. This stage is also the core of many other proliferative diseases. The present work proposes the first minimal model that combines homeorhesis with oncogenic hyperplasia where the latter is regarded as a genotoxically activated homeorhetic dysfunction. This dysfunction is specified as the transitions of the fluid of cells from a fluid, homeorhetic state to a solid, hyperplastic-tumor state, and back. The key part of the model is a nonlinear reaction-diffusion equation (RDE) where the biochemical-reaction rate is generalized to the one in the well-known Schlögl physical theory of the non-equilibrium phase transitions. A rigorous analysis of the stability and qualitative aspects of the model, where possible, are presented in detail. This is related to the spatially homogeneous case, i.e. when the above RDE is reduced to a nonlinear ordinary differential equation. The mentioned genotoxic activation is treated as a prevention of the quiescent G0-stage of the cell cycle implemented with the threshold mechanism that employs the critical concentration of the cellular fluid and the nonquiescent-cell-duplication time. The continuous tumor morphogeny is described by a time-space-dependent cellular-fluid concentration. There are no sharp boundaries (i.e. no concentration jumps exist) between the domains of the homeorhesis- and tumor-cell populations. No presumption on the shape of a tumor is used. To estimate a tumor in specific quantities, the model provides the time-dependent tumor locus, volume, and boundary that also points out the tumor shape and size. The above features are indispensable in the quantitative development of antiproliferative drugs or therapies and strategies to prevent oncogenic hyperplasia in cancer and other proliferative diseases. The work proposes an analytical-numerical method for solving the aforementioned RDE. A few topics for future research are suggested.
21.	Mamontov, Eugen, 1955, et al. (author) Oncogenic hyperplasia caused by combination of various factors: A decision-support software for radionuclide therapy 2007 In: Workshop "Mathematical Modelling and Analysis of Cancer Invasion of Tissues", Mar 26, 2007 - Mar 30, 2007, Dundee, Scotland. Conference paper (peer-reviewed)abstract The present work deals with the software based on the PhasTraM model [1] for oncogenic hyperplasia, the first stage of formation of any solid tumor. The work generalizes the related results of [2]-[6] and discusses application of the software for decision support in radionuclide therapy. The software capabilities to allow for combinations of various causes of oncogeny are emphasized. The causes comprise inflammation, immune dysfunction, and chronic psychological stress. The immune dysfunction is represented with hypogammaglobulenimia expressed in terms of the concentration of the immunoglobulin-G molecules. The level of chronic pychological stress is described with the concentration of the interleukin-6 molecules. The work considers how application of the software can support decisions on the specific radionuclide-therapy setting depending on the tissue-, organ-, and patient-specific data. This is illustrated by a number of numerical-simulation results, also the ones which include the effects of common and fractionation-based radionuclide-therapy modalities. A proper attention is paid to how specifically the input data can be prepared by prospective users of the software, i.e. the specialists who apply radionuclide therapy. The work also formulates a few directions for future research in connection with the features of the everyday work of the prospective users. REFERENCES: [1] E. Mamontov, K. Psiuk-Maksymowicz, A. Koptioug, 2006, Stochastic mechanics in the context of the properties of living systems, Mathl Comput. Modelling, 44(7-8) 595-607. [2] E. Mamontov, A. V. Koptioug, K. Psiuk-Maksymowicz, 2006, The minimal, phase-transition model for the cell-number maintenance by the hyperplasia-extended homeorhesis, Acta Biotheoretica, 54(2) 61-101. [3] K. Psiuk-Maksymowicz and E. Mamontov, 2006, The homeorhesis-based modelling and fast numerical analysis for oncogenic hyperplasia under radiotherapy, Mathl Comput. Modelling, Special Issue
22.	Olsen, Steen, et al. (author) Creatine supplementation augments the increase in satellite cell and myonuclei number in human skeletal muscle induced by strength training 2006 In: Journal of Physiology. - : Wiley. - 0022-3751 .- 1469-7793. ; 573:Pt 2, s. 525-534 Journal article (peer-reviewed)abstract The present study investigated the influence of creatine and protein supplementation on satellite cell frequency and number of myonuclei in human skeletal muscle during 16 weeks of heavy-resistance training. In a double-blinded design 32 healthy, male subjects (19-26 years) were assigned to strength training (STR) while receiving a timed intake of creatine (STR-CRE) (n=9), protein (STR-PRO) (n=8) or placebo (STR-CON) (n=8), or serving as a non-training control group (CON) (n=7). Supplementation was given daily (STR-CRE: 6-24 g creatine monohydrate, STR-PRO: 20 g protein, STR-CON: placebo). Furthermore, timed protein/placebo intake were administered at all training sessions. Muscle biopsies were obtained at week 0, 4, 8 (week 8 not CON) and 16 of resistance training (3 days per week). Satellite cells were identified by immunohistochemistry. Muscle mean fibre (MFA) area was determined after histochemical analysis. All training regimes were found to increase the proportion of satellite cells, but significantly greater enhancements were observed with creatine supplementation at week 4 (compared to STR-CON) and at week 8 (compared to STR-PRO and STR-CON) (P<0.01-0.05). At week 16, satellite cell number was no longer elevated in STR-CRE, while it remained elevated in STR-PRO and STR-CON. Furthermore, creatine supplementation resulted in an increased number of myonuclei per fibre and increases of 14-17% in MFA at week 4, 8 and 16 (P<0.01). In contrast, STR-PRO showed increase in MFA only in the later (16 week, +8%) and STR-CON only in the early (week 4, +14%) phases of training, respectively (P<0.05). In STR-CRE a positive relationship was found between the percentage increases in MFA and myonuclei from baseline to week 16, respectively (r=0.67, P<0.05). No changes were observed in the control group (CON). In conclusion, the present study demonstrates for the first time that creatine supplementation in combination with strength training amplifies the training-induced increase in satellite cell number and myonuclei concentration in human skeletal muscle fibres, thereby allowing an enhanced muscle fibre growth in response to strength training.
23.	Schagatay, Erika, et al. (author) Selected contribution: role of spleen emptying in prolonging apneas in humans 2001 In: Journal of Applied Physiology. - 1522-1601 .- 8750-7587. ; 90:4, s. 9-1623 Journal article (peer-reviewed)abstract This study addressed the interaction between short-term adaptation to apneas with face immersion and erythrocyte release from the spleen. Twenty healthy volunteers, including ten splenectomized subjects, participated. After prone rest, they performed five maximal-duration apneas with face immersion in 10 degrees C water, with 2-min intervals. Cardiorespiratory parameters and venous blood samples were collected. In subjects with spleens, hematocrit and hemoglobin concentration increased by 6.4% and 3.3%, respectively, over the serial apneas and returned to baseline 10 min after the series. A delay of the physiological breaking point of apnea, by 30.5% (17 s), was seen only in this group. These parameters did not change in the splenectomized group. Plasma protein concentration, preapneic alveolar PCO2, inspired lung volume, and diving bradycardia remained unchanged throughout the series in both groups. Serial apneas thus triggered the hematological changes that have been previously observed after long apneic diving shifts; they were rapidly reversed and did not occur in splenectomized subjects. This suggests that splenic contraction occurs in humans as a part of the diving response and may prolong repeated apneas.
24.	Ruiz, Jonatan R., et al. (author) Relations of total physical activity and intensity to fitness and fatness in children : the European Youth Heart Study 2006 In: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 84:2, s. 299-303 Journal article (peer-reviewed)abstract Background: It is unclear how the amount and intensity of physical activity (PA) are associated with cardiovascular fitness (CVF) and body fatness in children.Objective: We aimed to examine the associations of total PA and intensity levels to CVF and fatness in children.Design: A cross-sectional study of 780 children aged 9–10 y from Sweden and Estonia was conducted. PA was measured by accelerometry and was expressed as min/d of total PA, moderate PA, and vigorous PA. CVF was measured with a maximal ergometer bike test and was expressed as W/kg. Body fat was derived from the sum of 5 skinfold-thickness measurements. Multiple regression analysis was used to determine the degree to which variance in CVF and body fat was explained by PA, after control for age, sex, and study location.Results: Lower body fat was significantly associated with higher levels of vigorous PA, but not with moderate or total PA. Those children who engaged in >40 min vigorous PA/d had lower body fat than did those who engaged in 10–18 min vigorous PA/d. Total PA, moderate PA, and vigorous PA were positively associated with CVF. Those children who engaged in >40 min vigorous PA/d had higher CVF than did those who accumulated <18 min vigorous PA/d.Conclusions: The results suggest that PA of vigorous intensity may have a greater effect on preventing obesity in children than does PA of lower intensity, whereas both total and at least moderate to vigorous PA may improve children's CVF.
25.	Eriksson, Anders, et al. (author) Skeletal muscle morphology in power-lifters with and without anabolic steroids 2005 In: Histochemistry and Cell Biology. - : Springer Science and Business Media LLC. - 0948-6143 .- 1432-119X. ; 124:2, s. 167-175 Journal article (peer-reviewed)abstract The morphological appearance of the vastus lateralis (VL) muscle from high-level power-lifters on long-term anabolic steroid supplementation (PAS) and power-lifters never taking anabolic steroids (P) was compared. The effects of long- and short-term supplementation were compared. Enzyme-immunohistochemical investigations were performed to assess muscle fiber type composition, fiber area, number of myonuclei per fiber, internal myonuclei, myonuclear domains and proportion of satellite cells. The PAS group had larger type I, IIA, IIAB and IIC fiber areas (p<0.05). The number of myonuclei/fiber and the proportion of central nuclei were significantly higher in the PAS group (p<0.05). Similar results were seen in the trapezius muscle (T) but additionally, in T the proportion of fibers expressing developmental myosin isoforms was higher in the PAS group compared to the P group. Further, in VL, the PAS group had significantly larger nuclear domains in fibers containing > or = 5 myonuclei. The results of AS on VL morphology in this study were similar to previously reported short-term effects of AS on VL. The initial effects from AS appear to be maintained for several years.
26.	Kadi, Fawzi, et al. (author) Effects of one bout of endurance exercise on the expression of myogenin in human quadriceps muscle 2004 In: Histochemistry and Cell Biology. - : Springer Science and Business Media LLC. - 0948-6143 .- 1432-119X. ; 121:4, s. 329-334 Journal article (peer-reviewed)abstract The objective of this study was to investigate the cellular localisation of MyoD and myogenin in human skeletal muscle fibres as well as the possible alterations in the expression of MyoD and myogenin in response to a single bout of endurance exercise at 40% and 75% of maximum oxygen uptake (VO(2) max). Twenty-five biopsies (5 per subject) from the vastus lateralis muscle were obtained before exercise, from the exercising leg at 40% and 75% of VO(2) max and from the resting leg following these exercise bouts. The tyramide signal amplification-direct and the Vectastain ABC methods using specific monoclonal antibodies were used to determine the exact location of myogenin and MyoD, to identify muscle satellite cells and to determine myosin heavy chain (MyHC) composition. At rest, myonuclei did not express MyoD or myogenin. Following a single bout of exercise at 40% and 75% of VO(2) max, an accumulation of myogenin in myonuclei and not in satellite cells was observed in biopsies from the exercised leg but not in biopsies before exercise and from the resting leg. The number of myogenin-positive myonuclei varied among individuals indicating differences in the response to a single exercise bout. In conclusion, this immunohistochemical study showed that a rapid rearrangement of myogenin expression occurs in exercised human skeletal muscles in response to a single bout of exercise.
27.	Kadi, Fawzi, 1970- (author) Fysisk träning och telomerer 2008 In: Svensk Idrottsforskning. - 1103-4629. ; :2, s. 20-21 Journal article (other academic/artistic)
28.	Kadi, Fawzi (author) Hormonal and growth factor-related mechanisms involved in the adaptation of skeletal muscle to exercise 2005 In: The endocrine system in sports and exercise. - Malden, Mass. : Blackwell Publishing. - 1405130172 ; , s. 306-318 Book chapter (other academic/artistic)
29.	Kadi, Fawzi, et al. (author) The effects of heavy resistance training and detraining on satellite cells in human skeletal muscles 2004 In: Journal of Physiology. - : Wiley. - 0022-3751 .- 1469-7793. ; 558:Pt 3, s. 1005-1012 Journal article (peer-reviewed)abstract The aim of this study was to investigate the modulation of satellite cell content and myonuclear number following 30 and 90 days of resistance training and 3, 10, 30, 60 and 90 days of detraining. Muscle biopsies were obtained from the vastus lateralis of 15 young men (mean age: 24 years; range: 20-32 years). Satellite cells and myonuclei were studied on muscle cross-sections stained with a monoclonal antibody against CD56 and counterstained with Mayer's haematoxylin. Cell cycle markers CyclinD1 and p21 mRNA levels were determined by Northern blotting. Satellite cell content increased by 19% (P= 0.02) at 30 days and by 31% (P= 0.0003) at 90 days of training. Compared to pre-training values, the number of satellite cells remained significantly elevated at 3, 10 and 60 days but not at 90 days of detraining. The two cell cycle markers CyclinD1 and p21 mRNA significantly increased at 30 days of training. At 90 days of training, p21 was still elevated whereas CyclinD1 returned to pre-training values. In the detraining period, p21 and CyclinD1 levels were similar to the pre-training values. There were no significant alterations in the number of myonuclei following the training and the detraining periods. The fibre area controlled by each myonucleus gradually increased throughout the training period and returned to pre-training values during detraining. In conclusion, these results demonstrate the high plasticity of satellite cells in response to training and detraining stimuli and clearly show that moderate changes in the size of skeletal muscle fibres can be achieved without the addition of new myonuclei.
30.	Kadi, Fawzi, 1970- (author) Vägen mot effektivare styrketräning för nybörjare : en eller flera serier? 2006 In: Svensk Idrottsforskning. - 1103-4629. ; :3, s. 16-19 Journal article (other academic/artistic)
31.	Larsson, Barbro, 1952-, et al. (author) Surface electromyography and peak torque of repetitive maximum isokinetic plantar flexions in relation to aspects of muscle morphology 2006 In: Journal of Electromyography & Kinesiology. - : Elsevier BV. - 1050-6411 .- 1873-5711. ; 16:3, s. 281-290 Journal article (peer-reviewed)abstract This study investigates the relationships between surface electromyography (EMG [Mean frequency of the power spectrum (MNF)]) and peak torque variables obtained during 100 maximum concentric plantar flexions with the right limb at 60 degrees s(-1) and different muscle morphological variables. Surface EMG was recorded from the right gastrocnemius lateralis and muscle biopsies were taken from the same site as the EMG electrodes were positioned. Muscle fibre area and fibre type composition were determined on serial muscle cross sections using both histochemistry (myofibrillar adenosine triphosphatase) and immunohistochemistry (monoclonal antibodies against specific myosin heavy chain isoforms). Forty-three female and nine male students participated in the study. Gastrocnemius lateralis contained predominantly type I fibres (50%) and type IIA fibres (40%) in both sexes and large individual differences were found. Principal component analysis (PCA) was used for the intercorrelation analyses, and projection to latent structures (PLS) was used for the multivariate regression analysis. MNF correlated positively with different fibre areas and with the proportion of type I fibres. Fibre areas and sex were the most important factors in the regression of maximum peak torque. High proportion of type I fibres and sex were the most important regressors of peak torque endurance normalised for lean body mass. More studies are needed to understand the complex interrelationships between intrinsic muscle properties and the frequency content of the surface EMG before theoretical models can be formulated that incorporate both fibre areas and fibre type proportions.
32.	Mascher, Henrik, et al. (author) Changes in signalling pathways regulating protein synthesis in human muscle in the recovery period after endurance exercise 2007 In: Acta Physiologica. - : Blackwel. - 1748-1708 .- 1748-1716. ; 191:1, s. 67-75 Journal article (peer-reviewed)abstract AIM: Exercise induced alterations in the rate of muscle protein synthesis may be related to activity changes in signalling pathways involved in protein synthesis. The aim of the present study was to investigate whether such changes in enzyme phosphorylation occur after endurance exercise. METHODS: Six male subjects performed ergometer cycling exercise for 1 h at 75% of the maximal oxygen uptake. Muscle biopsy samples from the vastus lateralis were taken before, immediately after, 30 min, 1 h, 2 h and 3 h after exercise for the determination of protein kinase B (PKB/Akt), mammalian target of rapamycin (mTOR), glycogen synthase 3 kinase (GSK-3), p70S6 kinase (p70(S6k)) and eukaryotic elongation factor 2 (eEF2) phosphorylation. RESULTS: The phosphorylation of Akt was unchanged directly after exercise, but two- to fourfold increased 1 and 2 h after the exercise, whereas GSK-3alpha and beta phosphorylation were two- to fourfold elevated throughout most of the 3-h recovery period. Phosphorylation of mTOR was elevated threefold directly after, 30 min and 2 h after exercise and eEF2 phosphorylation was decreased by 35-75% from 30 min to 3 h-recovery. Exercise led to a five- to eightfold increase in Ser(424)/Thr(421) phosphorylation of p70(S6k) up to 30 min after exercise, but no change in Thr(389) phosphorylation. CONCLUSIONS: The marked decrease in eEF2 phosphorylation suggests an activation of translation elongation and possibly protein synthesis in the recovery period after sustained endurance exercise. The lack of p70(S6k) activation suggests that translation initiation is activated via alternative pathways, possibly via the activation of eukaryotic initiating factor 2B.
33.	Ponsot, Elodie, 1973-, et al. (author) Signal modelization for improved precision of assessment of minimum and mean telomere lengths 2008 In: Electrophoresis. - : Wiley-VCH Verlagsgesellschaft. - 0173-0835 .- 1522-2683. ; 29:2, s. 542-544 Journal article (peer-reviewed)abstract Telomere length is an important measure of cell and tissue regenerative capacities. The mean telomere length is classically used as global indicator of a tissue telomere length. In skeletal muscle, which is made of postmitotic myonuclei and satellite cells (muscle stem cells), minimum telomere length is also used to assess the telomere length of satellite cells and newly incorporated myonuclei. At present, the estimation of the method reproducibility during the assessment of mean and minimum telomere length using Southern blot analysis has never been documented. The aim of this report is to describe a signal modelization for improved precision of assessment of minimum and mean telomere lengths and to document the method reproducibility. Telomeres are assessed using a Southern technique where the gel is directly hybridized with the specific probe without the membrane-transferring step in order to prevent telomeric low signal loss. We found that the improved signal analysis for determination of telomere length is associated with coefficients of variation ranging from 1.37 to 4.29% for the mean telomeric restriction fragment (TRF) length and from 2.04 to 4.95% for the minimum TRF length. Improved method reproducibility would allow saving time and biological material as duplicate and triplicate measurement of the same sample is no longer required.
34.	Verney, Julien, et al. (author) Effects of combined lower body endurance and upper body resistance training on the satellite cell pool in elderly subjects 2008 In: Muscle and Nerve. - : Wiley. - 0148-639X .- 1097-4598. ; 38:3, s. 1147-1154 Journal article (peer-reviewed)abstract To distinguish the respective potential of endurance and resistance training to increase the satellite cell pool, we investigated the effects of 14 weeks of concurrent lower body endurance and upper body resistance training (3 sessions/week) on vastus lateralis (VLat) and deltoid (Del) muscles of 10 active elderly men. NCAM+ satellite cells and myonuclear number were assessed in VLat and Del. After 14 weeks of training the NCAM+ satellite cell pool increased similarly (+38%) in both muscles, mainly in type II muscle fibers (P < 0.05). There was no significant change in myonuclear number or myonuclear domain in either muscle. Combining resistance training in the upper limbs with endurance training in the lower limbs is an efficient strategy to enhance the satellite cell pool in upper and lower body muscles in elderly subjects. Our results provide a practical reference for the determination of optimal exercise protocols to improve muscle function and regeneration in the elderly.
35.	Dyachok, Oleg, et al. (author) Ca2+-induced Ca2+ Release via Inositol 1,4,5-trisphosphate Receptors Is Amplified by Protein Kinase A and Triggers Exocytosis in Pancreatic β-Cells 2004 In: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 279:44, s. 45455-45461 Journal article (peer-reviewed)abstract Hormones, such as glucagon and glucagon-like peptide-1, potently amplify nutrient stimulated insulin secretion by raising cAMP. We have studied how cAMP affects Ca2+-induced Ca2+ release (CICR) in pancreatic β-cells from mice and rats and the role of CICR in secretion. CICR was observed as pronounced Ca2+ spikes on top of glucose- or depolarization-dependent rise of the cytoplasmic Ca2+ concentration ([Ca2+]i). cAMP-elevating agents strongly promoted CICR. This effect involved sensitization of the receptors underlying CICR, because many cells exhibited the characteristic Ca2+ spiking at low or even in the absence of depolarization-dependent elevation of [Ca2+]i. The cAMP effect was mimicked by a specific activator of protein kinase A in cells unresponsive to activators of cAMP-regulated guanine nucleotide exchange factor. Ryanodine pretreatment, which abolishes CICR mediated by ryanodine receptors, did not prevent CICR. Moreover, a high concentration of caffeine, known to activate ryanodine receptors independently of Ca2+, failed to mobilize intracellular Ca2+. On the contrary, a high caffeine concentration abolished CICR by interfering with inositol 1,4,5-trisphosphate receptors (IP3Rs). Therefore, the cell-permeable IP3R antagonist 2-aminoethoxydiphenyl borate blocked the cAMP-promoted CICR. Individual CICR events in pancreatic β-cells were followed by [Ca2+]i spikes in neighboring human erythroleukemia cells, used to report secretory events in the β-cells. The results indicate that protein kinase A-mediated promotion of CICR via IP3Rs is part of the mechanism by which cAMP amplifies insulin release.
36.	Andersson, Christin, et al. (author) Increasing CSF phospho-tau levels during cognitive decline and progression to dementia 2008 In: Neurobiology of Aging. - : Elsevier BV. - 0197-4580 .- 1558-1497. ; 29:10, s. 1466-1473 Journal article (peer-reviewed)abstract BACKGROUND: Little is known about longitudinal changes of cerebrospinal fluid (CSF) biomarkers during cognitive decline in neurodegenerative disease progression. OBJECTIVE: To investigate longitudinal changes in CSF biomarkers--total-tau (T-tau), phospho-tau (P-tau) and beta-amyloid (Abeta42)--during cognitive decline. METHODS: Forty memory clinic patients (47.5% females), aged 61.3+/-7.6 (S.D.) years, non-demented at baseline, underwent lumbar puncture and neuropsychological testing at two occasions. Baseline mean MMSE-score was 28.3+/-1.8. Patients were divided into three groups based on baseline memory functioning; severely impaired (SIM), moderately impaired (MIM) and no impairment (NIM). RESULTS: There was a significant increase in P-tau in the SIM-group during follow-up, while P-tau in MIM and NIM did not change. Eighty-three percent of the SIM-patients converted to dementia (80% AD), while most MIM- and NIM-patients remained non-demented. T-tau- and Abeta42-levels did not change in any of the memory groups during follow-up. CONCLUSION: Increasing P-tau levels during cognitive decline and conversion to dementia suggest that P-tau may be useful as a longitudinal marker of the neurodegenerative process.
37.	Cain, Peter, et al. (author) Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects 2005 In: Clin Physiol Funct Imaging. - 1475-0961. ; 25:6, s. 332-9 Journal article (peer-reviewed)abstract BACKGROUND: The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics. METHODS: A total of 102 healthy volunteers (12-81 years, 53 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents <20 years, adults > or = 20 years). The influence of haemodynamic factors, exercise, and demographic factors on LVM were determined with multivariate linear regression. Results: LVM rose during adolescence and declined in adulthood. LVM and LVMBSA were higher in males both in adults (LVM: 188 +/- 22 g versus 139 +/- 21 g, P < 0.001; LVMBSA: 94 +/- 11 g m(-2) versus 80 +/- 11 g m(-2), P < 0.001) and in adolescents when adjusted for BSA (LVM: 128 +/- 29 g versus 107 +/- 20 g, P = 0.063; LVMBSA: 82 +/- 8 g m(-2) versus 71 +/- 10 g m(-2), P = 0.025). In adults, systolic blood pressure (SBP) and self-reported physical activity increased while meridional and circumferential wall stress were constant with age. Multivariate regression analysis revealed age, gender, and BSA as the major determinants of LVM (global R2 = 0.69). CONCLUSIONS: Normal LVM shows variation over a broad age range in both genders with a rise in adolescence and subsequent decline with increasing age in adulthood despite an increase in SBP and physical activity. BSA, age, and gender were found to be major contributors to the variation in LVM in healthy adults, while haemodynamic factors, exercise, and wall stress were not.
38.	Almon, Ricardo, 1965-, et al. (author) Associations between lactase persistence and the metabolic syndrome : a Mendelian randomization study in the Canary Islands 2009 Conference paper (peer-reviewed)
39.	Ryman Augustsson, Sofia, et al. (author) Injuries and preventive actions in elite Swedish volleyball. 2006 In: Scandinavian journal of medicine & science in sports. - : Wiley. - 0905-7188 .- 1600-0838. ; 16:6, s. 433-40 Journal article (peer-reviewed)abstract The purpose of this study was to examine the prevalence of injury and the extent of preventive actions in elite Swedish volleyball players. Injuries to players in the elite male and female Swedish division, during the 2002-2003 season, were registered by using a questionnaire. Of the 158 volleyball players (70% response rate), a total of 82 players (52%) reported 121 injuries, during a total exposure time of 24 632 h, representing an overall incidence of 0.77 injuries per player. The majority of the injuries were located in the ankle (23%), followed by the knee (18%) and the back (15%). Most injuries (62%) were classified as being of minor severity. Most injuries occurred during training (47%), and 41% of the injuries had a gradual onset. Fifty-four percent of the injuries that could be related to a specific court situation occurred during blocking, and 30% during spiking. Most players (96%) participated in injury prevention training of some kind, generally performed without supervision (58%). Although most players took part in some kind of preventive action, one out of two players incurred an injury during the season, which indicates that the risk of suffering an injury in elite volleyball is relatively high.
40.	Länne, T, et al. (author) Decreased capacitance response with age in lower limbs of humans--a potential error in the study of cardiovascular reflexes in ageing 1997 In: Acta Physiologica Scandinavica. - 0001-6772. ; 161:4, s. 7-503 Journal article (peer-reviewed)abstract The cardiovascular regulation in humans depends to a major extent on sympathetic reflexes originating from volume receptors in the arterial as well as the cardiopulmonary region. With experimental approaches, such as lower body negative pressure (LBNP) and tilting, signs of reduced efficiency with ageing have been shown. However, a confounding factor may be an age-related decline in venous capacitance response of the lower limbs, reducing the decrease in central blood volume and thus the deactivation of baro/cardiopulmonary receptors. This potential error was addressed in the present study. Central hypovolaemic stress was produced by LBNP 60 cmH2O in 10 young (mean age 23, range 20-25 years) and 10 old males (mean age 65, range 61-70 years). Changes in tissue volume of the calf were studied by strain gauge volumetric technique. Transmission of negative pressure to the calf muscle was studied in two young and two old volunteers. The haemodynamic response to hypovolaemic circulatory stress was attenuated in the old as compared with the young subjects, with a less marked increase in heart rate and peripheral resistance. Further, in the old subjects, the decrease in systolic blood pressure, pulse pressure and forearm blood flow was attenuated. Transmission of negative pressure to the calf was equal in both groups. The capacitance response was reduced with age from 2.27 +/- 0.14 to 1.64 +/- 0.13 mL 100 mL-1 (P < 0.005). However, the net capillary fluid filtration was unchanged. The reduced capacitance function might partly explain the declining reflex responses with age in humans, and thus seems to be of considerable importance when studying cardiovascular sympathetic reflex responses in ageing.
41.	Dyverfeldt, Petter, 1980-, et al. (author) Quantification of intravoxel velocity standard deviation and turbulence intensity by generalizing phase-contrast MRI 2006 In: Magnetic Resonance in Medicine. - : Wiley. - 0740-3194 .- 1522-2594. ; 56:4, s. 850-858 Journal article (peer-reviewed)abstract Turbulent flow, characterized by velocity fluctuations, is a contributing factor to the pathogenesis of several cardiovascular diseases. A clinical noninvasive tool for assessing turbulence is lacking, however. It is well known that the occurrence of multiple spin velocities within a voxel during the influence of a magnetic gradient moment causes signal loss in phase-contrast magnetic resonance imaging (PC-MRI). In this paper a mathematical derivation of an expression for computing the standard deviation (SD) of the blood flow velocity distribution within a voxel is presented. The SD is obtained from the magnitude of PC-MRI signals acquired with different first gradient moments. By exploiting the relation between the SD and turbulence intensity (TI), this method allows for quantitative studies of turbulence. For validation, the TI in an in vitro flow phantom was quantified, and the results compared favorably with previously published laser Doppler anemometry (LDA) results. This method has the potential to become an important tool for the noninvasive assessment of turbulence in the arterial tree.
42.	Wallén-Mackenzie, Åsa, et al. (author) Restricted cortical and amygdaloid removal of vesicular glutamate transporter 2 in preadolescent mice impacts dopaminergic activity and neuronal circuitry of higher brain function. 2009 In: The Journal of neuroscience : the official journal of the Society for Neuroscience. - 1529-2401 .- 0270-6474. ; 29:7, s. 2238-51 Journal article (peer-reviewed)abstract A major challenge in neuroscience is to resolve the connection between gene functionality, neuronal circuits, and behavior. Most, if not all, neuronal circuits of the adult brain contain a glutamatergic component, the nature of which has been difficult to assess because of the vast cellular abundance of glutamate. In this study, we wanted to determine the role of a restricted subpopulation of glutamatergic neurons within the forebrain, the Vglut2-expressing neurons, in neuronal circuitry of higher brain function. Vglut2 expression was selectively deleted in the cortex, hippocampus, and amygdala of preadolescent mice, which resulted in increased locomotor activity, altered social dominance and risk assessment, decreased sensorimotor gating, and impaired long-term spatial memory. Presynaptic VGLUT2-positive terminals were lost in the cortex, striatum, nucleus accumbens, and hippocampus, and a downstream effect on dopamine binding site availability in the striatum was evident. A connection between the induced late-onset, chronic reduction of glutamatergic neurotransmission and dopamine signaling within the circuitry was further substantiated by a partial attenuation of the deficits in sensorimotor gating by the dopamine-stabilizing antipsychotic drug aripiprazole and an increased sensitivity to amphetamine. Somewhat surprisingly, given the restricted expression of Vglut2 in regions responsible for higher brain function, our analyses show that VGLUT2-mediated neurotransmission is required for certain aspects of cognitive, emotional, and social behavior. The present study provides support for the existence of a neurocircuitry that connects changes in VGLUT2-mediated neurotransmission to alterations in the dopaminergic system with schizophrenia-like behavioral deficits as a major outcome.
43.	Andersson, Johan, et al. (author) Arterial oxygen desaturation during apnea in humans 1998 In: Undersea & Hyperbaric Medicine. - 1066-2936. ; 25:1, s. 5-21 Journal article (peer-reviewed)abstract We studied the effect of the human diving response, defined as bradycardia and reduced peripheral blood flow, on arterial hemoglobin desaturation. We induced a diving response of different magnitudes by using apnea in air and apnea with face immersion. Each of 21 subjects performed five apneas in air and five apneas with face immersion in 10 degrees C water. Periods of apnea in both conditions were of the same duration in any individual subject (average: 126.4 s) and the order of air and water was equally distributed among subjects. Heart rate, skin capillary blood flow, arterial blood pressure, arterial hemoglobin oxygen saturation during apneas, and end-tidal fractions of CO2 after apneas were recorded with non-invasive methods. The bradycardia and capillary blood flow reduction during apnea in air (7.8 and 37.7% change from control, respectively) were significantly potentiated by face immersion (13.6 and 55.9%, respectively). Arterial hemoglobin desaturated more during apnea in air (2.7%) compared to during apnea with face immersion (1.4%). We conclude that the potentiation of the human diving response with face immersion in cold water leads to a smaller decrease in arterial hemoglobin saturation, which may reflect an oxygen-conserving effect.
44.	Schagatay, Erika, et al. (author) Diving response and apneic time in humans 1998 In: Undersea & Hyperbaric Medicine. - 1066-2936. ; 25:1, s. 9-13 Journal article (peer-reviewed)abstract The aim of this study was to compare apneic time with the human diving response, defined as heart rate (HR) reduction and reduced skin blood flow, in groups with varying degrees of breath-hold diving experience. Apneic time and HR reduction at apneas in air and apneas with face immersion in cold water were thus recorded in nine groups. Skin capillary blood flow was recorded in six of the groups. All subjects received the same information on maximizing apneic duration, and no information about their progress during the apneas. The longest apneas and the most pronounced cardiovascular adjustments were found in the young, trained divers. It was found that apneic time was significantly correlated to HR reduction among the nine groups (r = 0.94, P < 0.001), and to skin capillary blood flow reduction among the six groups where the parameter was measured (r = 0.82, P < 0.05). The correlation between HR reduction and skin capillary blood flow reduction was also significant (r = 0.85, P < 0.05). When the difference in HR reduction and apneic time between apneas in air and apneas with face immersion were compared in the nine groups, it was found that all groups reacted with a more pronounced HR reduction during apneas with face immersion. All groups without prior breath-hold diving experience were found to perform shorter apneas with face immersion than apneas in air, or apneas of the same duration in both conditions, which has been reported in other studies. However, in all groups with diving experience, the apneic time was prolonged during apneas with face immersion. The results of this study suggest an oxygen-conserving effect of the diving response in trained apneic divers.
45.	Backhaus, Thomas, 1967, et al. (author) Toxicity of a mixture of dissimilarly acting substances to natural algal communities: predictive power and limitations of independent action and concentration addition. 2004 In: Environmental science & technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 38:23, s. 6363-70 Journal article (peer-reviewed)abstract Predictive studies of chemical mixtures are typically based on experiments with single species. To study the applicability of the concepts of independent action (IA) and concentration addition (CA) on a multispecies level, the carbon fixation of natural algal communities under toxicant exposure was studied. The presented study focused on a mixture of six dissimilarly acting substances. Conceptual reasoning as well as empirical evidence from single-species tests suggest that IA is more appropriate for this type of mixture. Nonetheless, the potential of CA was also investigated, to assess whether this concept may be applicable as a reasonable worst case prediction of mixture toxicities also on a community level. IA predicted the experimental EC50 precisely. CA underestimated the EC50 by a factor of only 1.4, although the shape of the predicted concentration-response curve was clearly different from experimental data. Hence, it can be concluded that the applicability of the concepts is not restricted to the level of single species. However, some limitations of both concepts became apparent, when stimulating (hormesis-like) effects were observed fo rtwo of the mixture components. These effects were also seen in the experimental mixture toxicity data but cannot be adequately modeled by either concept.
46.	Robinson, Yohan, 1977, et al. (author) Intravascular hemolysis and mean red blood cell age in athletes. 2006 In: Medicine and science in sports and exercise. - : Ovid Technologies (Wolters Kluwer Health). - 0195-9131 .- 1530-0315. ; 38:3, s. 480-3 Journal article (peer-reviewed)abstract Since the observation that mechanical stress causes red blood cell (RBC) destruction, foot-strike hemolysis has been used to explain sports anemia and RBC rejuvenation in athletes. Recently gained knowledge questions the importance of mechanical RBC trauma on RBC hemolysis in athletes.Male athletes (N = 90) and untrained male controls (N = 58) were investigated for aerobic performance, hematological parameters, serum erythropoietin concentration (EPO), soluble transferrin receptor concentration (sTFR), and erythrocyte aspartate aminotransferase activity (eAST).On hard floor running disciplines (HFR, N = 26, short- and long-distance runners, triathletes) showed a lower eAST (P < 0.001) and thus no younger RBC population than not on hard floor running athletes (NHFR, N = 64, cyclists, soccer players, others) or the untrained control group (N = 58). HFR had higher but still normal EPO (P < 0.01) and no higher sTFR.Because intravascular hemolysis occurs in swimmers, cyclists, and runners, and mean RBC age is not reduced in runners, mechanisms other than foot-strike hemolysis have to be considered as well. Possible reasons are intramuscular destruction, osmotic stress, and membrane lipid peroxidation caused by free radicals released by activated leukocytes. Intravascular hemolysis can even be regarded as physiological means to provide heme and proteins for muscle growth.
47.	Johansson, Christin, et al. (author) [Appeal from ten associations of health professionals: the government must quality-assure clinical research] : Regeringen måste kvalitetssäkra den kliniska forskningen 2008 In: Läkartidningen. - 0023-7205. ; 105:28-29 Journal article (other academic/artistic)
48.	Schagatay, Erika (author) The human diving response : effects of temperature and training 1996 Doctoral thesis (other academic/artistic)abstract The aim was to elucidate the cardiovascular response associated with breath-hold diving, especially the effects of temperature in its elicitation and the effects of different types of training on the human diving response (DR) and breath-holding time (BHT), and to evaluate the human DR in a mammalian perspective. A model for simulated diving by apnea and facial immersion in cold water was developed. Cardiovascular parameters were registred using non-invasive techniques. The bradycardia response to breath-holding and chilling of the forehead was found to be more pronounced than that obtained when other facial areas of the same size were chilled, indicating that the ophthalmic branch of the trigeminus nerve is the main sensory area for initiating bradycardia in humans. It was found that both water temperature and ambient air temperature had significant, but opposite, effects on the magnitude of bradycardia developed at apneic face immersion, and the results indicate that diving bradycardia is negatively correlated to wate temperature within a range that is determined by the ambient air temperature. Furthermore, it was found that there is an increase in BHT over five dives when diving is repeated with short intervals, due to a delay of the the physiologi- cal breaking point (PBP) up to dive three, while to an increased tolerance by the subject up to dive five. It was conclude that an increased diving response is not the cause of the prolonged BHT seen in repeated diving, as has been suggested. A positive correlation between individual BHT and maximum bradycardia at repeated diving was found. There was also a positive correlation between mean bradycardia, skin capillary blood flow reduction and BHT on the group level, with the trained divers showing the most pronounced DR and the longest BHT. In trained divers the increase in diving bradycardia seen during apnea with face immersion compared to during apnea in air was accompanied by an increase in diving time, which was not seen in untrained subjects. Physical training leading to increase in maximal oxygen uptake does not increase the time before the PBP or the diving bradycardia. However, the tolerance to IBM appears to be en- hanced after physical training, which prolongs the BHT. Apnea training leads to a delay of the PBP and an increased diving bradycardia and BHT, and may be an essential factor in dive training. It was concluded that a pronounced DR is not only genetically determined but appears as a result of training and disappears as a result of aging. Taken together, data suggest that the human DR may have an 02 conserving effect in trained divers. The mean DR of trained human divers is in the range of that of the beaver, a semiaquatic mammal, while that of untrained humans is in the range of the pig, a terrestrial species. It is hypothesized, based on the results concerning temperature dependence of the trigemi- nus cold-response in adults, that this response may be involved in the events leading to sudden infant death syndrome.
49.	Skarnemark, Gunnar, 1948 (author) Low-Energy Electron Emitters for Targeted Therapy of Small Tumors 2001 In: Acta Oncologica. ; 40:5, s. 602-608 Journal article (peer-reviewed)
50.	Oldberg, Åke, et al. (author) Collagen-binding proteoglycan fibromodulin can determine stroma matrix structure and fluid balance in experimental carcinoma. 2007 In: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 104:35, s. 13966-13971 Journal article (peer-reviewed)abstract Research on the biology of the tumor stroma has the potential to lead to development of more effective treatment regimes enhancing the efficacy of drug-based treatment of solid malignancies. Tumor stroma is characterized by distorted blood vessels and activated connective tissue cells producing a collagen-rich matrix, which is accompanied by elevated interstitial fluid pressure (IFP), indicating a transport barrier between tumor tissue and blood. Here, we show that the collagen-binding proteoglycan fibromodulin controls stroma structure and fluid balance in experimental carcinoma. Gene ablation or inhibition of expression by anti-inflammatory agents showed that fibromodulin promoted the formation of a dense stroma and an elevated IFP. Fibromodulin-deficiency did not affect vasculature but increased the extracellular fluid volume and lowered IFP. Our data suggest that fibromodulin controls stroma matrix structure that in turn modulates fluid convection inside and out of the stroma. This finding is particularly important in relation to the demonstration that targeted modulations of the fluid balance in carcinoma can increase the response to cancer therapeutic agents.

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