Records |
Author |
Bystrom, A.; Roepstorff, L.; Johnston, C. |
Title |
Effects of draw reins on limb kinematics |
Type |
Journal Article |
Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
Volume |
|
Issue |
36 |
Pages |
452-456 |
Keywords |
Animals; Biomechanics; Exercise Test; Forelimb/physiology; Head/physiology; Hindlimb/physiology; Horses/*physiology; Humans; Movement/physiology; Neck/physiology; Physical Conditioning, Animal/*methods/*physiology; Weight-Bearing/physiology |
Abstract |
REASONS FOR PERFORMING STUDY: No data exist on the GRF-kinematics relation due to changes caused by equestrian interventions. HYPOTHESIS: Through the judicious use of draw reins the rider can influence the kinematics of the horse to meet stated goals of dressage training. Relating the results to previously published kinetic data of the same experiment implies a possible relationship between kinetics and kinematics. METHODS: The kinematics of 8 sound Swedish Warmblood horses were measured whilst the horses were being ridden with and without draw reins. Three conditions were evaluated: 1) draw reins only (DR), 2) combination of draw reins and normal reins (NR+DR) and 3) normal reins only (NR). RESULTS: Head and neck angles were significantly decreased by the draw rein but 4-5 times more so for DR when with NR+DR. The forelimb position at hoof lift-off was significantly more caudal with DR. In the hind limb the hip joint extended more quickly and the hock joint flexed more with NR+DR than with NR. Compared to DR the hip joint angular pattern was not significantly different, but the pelvis was more horizontal. CONCLUSION: Riding with a draw rein can have significant influence on the kinematics of the horse. Some of the observed changes can be coupled to changes in kinetics. The hock joint angle seems to be a fairly reliable indicator of load on the hind limb and the angle of femur appears important for hind limb propulsion, when considered in conjunction with the orientation of the pelvis. POTENTIAL RELEVANCE: These findings are important for riders and trainers, as kinematic changes are what trainers observe. It is thereby important to ascertain which kinematic changes are consistently coupled to changes in kinetics in order for trainers to be able to judge correctly the success of intended goals. Further studies are warranted to validate and confirm suggested relationships between kinetics and kinematics. |
Address |
Department of Equine Studies, Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden |
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PMID:17402465 |
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no |
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Equine Behaviour @ team @ |
Serial |
3701 |
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Author |
Kaiser, L.; Smith, K.A.; Heleski, C.R.; Spence, L.J. |
Title |
Effects of a therapeutic riding program on at-risk and special education children |
Type |
Journal Article |
Year |
2006 |
Publication |
Journal of the American Veterinary Medical Association |
Abbreviated Journal |
J Am Vet Med Assoc |
Volume |
228 |
Issue |
1 |
Pages |
46-52 |
Keywords |
Adolescent; Anger; Animals; *Bonding, Human-Pet; Child; Child Behavior; *Child Psychology; Disabled Persons/*psychology/rehabilitation; Female; Horses; Humans; Mainstreaming (Education); Male; Mothers/*psychology; Occupational Therapy/*methods; Recreation; Self Efficacy; Sports/*psychology |
Abstract |
OBJECTIVE: To determine the effects of a therapeutic riding program on psychosocial measurements among children considered at risk for poor performance or failure in school or life and among children in special education programs. DESIGN: Observational study. POPULATION: 17 at-risk children (6 boys and 11 girls) and 14 special education children (7 boys and 7 girls). PROCEDURE: For the at-risk children, anger, anxiety, perceived self-competence, and physical coordination were assessed. For the special education children, anger and cheerfulness were measured, and the children's and their mothers' perceptions of the children's behavior were assessed. Measurements were made before and after an 8-session therapeutic riding program. RESULTS: For boys enrolled in the special education program, anger was significantly decreased after completion of the riding program. The boys' mothers also perceived significant improvements in their children's behavior after completion of the program. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that an 8-session therapeutic riding program can significantly decrease anger in adolescent boys in a special education program and positively affect their mothers' perception of the boys' behavior. |
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Human-Animal Bond Initiative, College of Nursing, Michigan State University, East Lansing, MI 48824, USA |
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0003-1488 |
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PMID:16426165 |
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no |
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1880 |
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Takahashi, T.; Kasashima, Y.; Eto, D.; Mukai, K.; Hiraga, A. |
Title |
Effect of uphill exercise on equine superficial digital flexor tendon forces at trot and canter |
Type |
Journal Article |
Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
Volume |
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Issue |
36 |
Pages |
435-439 |
Keywords |
Animals; Biomechanics; Exercise Test/veterinary; Female; Forelimb/physiology; Hoof and Claw/physiology; Horses/*physiology; Male; Physical Conditioning, Animal/*methods/*physiology; Tarsal Joints/*physiology; Tarsus, Animal; Tendon Injuries/etiology/prevention & control/veterinary; Time Factors |
Abstract |
REASONS FOR PERFORMING STUDY: One cause of overstrain injury to the superficial digital flexor tendon (SDFT) in horses is the force loaded on the SDFT during repeated running. Therefore, decreasing this force may reduce SDFT injury. It has been reported that strain on the SDFT decreases with a toe-wedge shoe. Uphill courses are used for training of racehorses, and the angle of hoof-sole to the horizon during uphill running is similar to that of the toe-wedge shoe. OBJECTIVES: To determine the effects of uphill exercise on the force on the SDFT during trotting and cantering. METHODS: Arthroscopically implantable force probes (AIFP) were implanted into the SDFT of the left or right forelimb of 7 Thoroughbred horses and AIFP output recorded during trotting and cantering on a treadmill inclined at slopes of 0, 3 or 8%, and then 0% again. Superficial digital flexor tendon force was calculated as a relative value, with the amplitude of AIFP output voltage at initial 0% slope equal to 100. RESULTS: Out of 14 sets of experiments, AIFP data were analysed successfully in 9 at the trot, in 3 at the canter in the trailing forelimb on a slope of 3 and 8%, and in 2 at the canter in the leading forelimb on a slope of 3%. Increasing the incline from 0-8% tended to decrease peak force in the SDFT at the trot, and in the trailing forelimb at the canter. However, force in the SDFT was unchanged in the leading forelimb at the canter on the 3% incline. CONCLUSIONS: The force in the SDFT trotting or cantering uphill is unchanged or lower than that loaded at the same speed on a flat surface. Because at similar speeds the workload for uphill exercise is greater than on the flat, uphill running increases exercise intensity without increasing force in the SDFT. POTENTIAL RELEVANCE: Uphill exercise may reduce the risk of SDFT injury as both running speed and SDFT force are decreased on an incline as compared to the flat, even when exercise intensity is the same. Further study is needed to confirm these findings at canter in a larger population of horses. |
Address |
Equine Research Institute, Japan Racing Association, 321-4 Tokami-cho, Utsunomiya, Tochigi 320-0856, Japan |
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PMID:17402462 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
4005 |
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Author |
Cottin, F.; Barrey, E.; Lopes, P.; Billat, V. |
Title |
Effect of repeated exercise and recovery on heart rate variability in elite trotting horses during high intensity interval training |
Type |
Journal Article |
Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
Volume |
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Issue |
36 |
Pages |
204-209 |
Keywords |
Animals; Electrocardiography/veterinary; Fatigue/diagnosis/*veterinary; Fourier Analysis; Heart Rate/*physiology; Horses/*physiology; Physical Conditioning, Animal/*methods/*physiology; Respiration; Time Factors |
Abstract |
REASONS FOR PERFORMING STUDY: Interval training is a commonly used training method for trotting horses. In addition, trainers are provided with efficient and inexpensive heart rate monitor devices for the management of training. HYPOTHESIS: Since the high frequency (HF) frequency peak (fHF) of heart rate variability (HRV) corresponds to the breathing frequency in combination with stride frequency during trotting, it is hypothesised that modifications of breathing and stride frequencies induced by repeated exercise could be detected from fHF. METHODS: RR interval time series of 7 trotting horses were recorded during an interval training session. Interval training was made up of 5 successive 800 m high-velocity trotting runs (H1, H2...H5) separated by 1 min recovery bouts at low speed (R1, R2...R5). Fast Fourier transform (FFT) and Poincare plot analysis techniques were applied to RR series. RESULTS: Repeated exercise had significant effects on HRV components during interval training. Despite constant trotting velocities during high-speed and recovery, repetition induced a decrease in mean RR interval (H1: 295 +/- 19 vs. H5: 283 +/- 15 msec, P<0.05) and in the root mean square of successive differences in RR series (RMSSD; H1: 6.31 +/- 1.28 vs. H5: 5.31 +/- 1.31 msec, P<0.05). Furthermore, high-speed and recovery repetitions induced an increase in fHF (H1: 1.37 +/- 0.35 vs. H5: 1.62 +/- 0.40 Hz and R1: 0.22 +/- 0.02 vs. R4: 0.64 +/- 0.38 Hz, P<0.05). Hence, recovery induced a decrease in the s.d. of the successive RR series (SDRR; R3: 10.5 +/- 3.96 vs. R5: 6.17 +/- 2.65 msecs, P>0.05) and in the long term index of Poincare plot (SD2; R1: 43.29 +/- 28.90 vs. R5: 18.19 +/- 9.35 msecs, P<0.05). CONCLUSIONS: The observed increase in fHF during the interval training could be induced by alterations of the coupling between breathing and stride frequency linked to the emergence of fatigue. The decrease in SD2 and SDRR during successive recovery bouts could be linked with a deterioration of the recovery pattern. POTENTIAL RELEVANCE: HRV can provide breathing frequency data of Standardbreds during training without any respiratory device. Furthermore, HRV could provide useful makers of the emergence of fatigue states during training. |
Address |
Laboratory of Exercise Physiology (LEPHE), University of Evry, E.A. 3872, Genopole, Boulevard F Mitterrand, F-91025 Evry cedex, France |
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PMID:17402419 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
4009 |
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Author |
Weishaupt, M.A.; Wiestner, T.; von Peinen, K.; Waldern, N.; Roepstorff, L.; van Weeren, R.; Meyer, H.; Johnston, C. |
Title |
Effect of head and neck position on vertical ground reaction forces and interlimb coordination in the dressage horse ridden at walk and trot on a treadmill |
Type |
Journal Article |
Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
Volume |
|
Issue |
36 |
Pages |
387-392 |
Keywords |
Animals; Biomechanics; Exercise Test/instrumentation/methods/*veterinary; Forelimb/physiology; Gait; Head/physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male; Neck/physiology; Physical Conditioning, Animal/methods/*physiology; Posture; Statistics, Nonparametric; Walking/*physiology |
Abstract |
REASONS FOR PERFORMING STUDY: Little is known in quantitative terms about the influence of different head-neck positions (HNPs) on the loading pattern of the locomotor apparatus. Therefore it is difficult to predict whether a specific riding technique is beneficial for the horse or if it may increase the risk for injury. OBJECTIVE: To improve the understanding of forelimb-hindlimb balance and its underlying temporal changes in relation to different head and neck positions. METHODS: Vertical ground reaction force and time parameters of each limb were measured in 7 high level dressage horses while being ridden at walk and trot on an instrumented treadmill in 6 predetermined HNPs: HNP1 – free, unrestrained with loose reins; HNP2 – neck raised, bridge of the nose in front of the vertical; HNP3 – neck raised, bridge of the nose behind the vertical; HNP4 – neck lowered and flexed, bridge of the nose considerably behind the vertical; HNP5 – neck extremely elevated and bridge of the nose considerably in front of the vertical; HNP6 – neck and head extended forward and downward. Positions were judged by a qualified dressage judge. HNPs were assessed by comparing the data to a velocity-matched reference HNP (HNP2). Differences were tested using paired t test or Wilcoxon signed rank test (P<0.05). RESULTS: At the walk, stride duration and overreach distance increased in HNP1, but decreased in HNP3 and HNP5. Stride impulse was shifted to the forehand in HNP1 and HNP6, but shifted to the hindquarters in HNP5. At the trot, stride duration increased in HNP4 and HNP5. Overreach distance was shorter in HNP4. Stride impulse shifted to the hindquarters in HNP5. In HNP1 peak forces decreased in the forelimbs; in HNP5 peak forces increased in fore- and hindlimbs. CONCLUSIONS: HNP5 had the biggest impact on limb timing and load distribution and behaved inversely to HNP1 and HNP6. Shortening of forelimb stance duration in HNP5 increased peak forces although the percentage of stride impulse carried by the forelimbs decreased. POTENTIAL RELEVANCE: An extremely high HNP affects functionality much more than an extremely low neck. |
Address |
Equine Hospital, University of Zurich, CH-8057 Zurich, Switzerland |
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PMID:17402453 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
3704 |
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Author |
Santamaria, S.; Bobbert, M.F.; Back, W.; Barneveld, A.; van Weeren, P.R. |
Title |
Effect of early training on the jumping technique of horses |
Type |
Journal Article |
Year |
2005 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
Volume |
66 |
Issue |
3 |
Pages |
418-424 |
Keywords |
Age Factors; Analysis of Variance; Animals; Biomechanics; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/growth & development/*physiology; Locomotion/*physiology; Models, Biological; Physical Conditioning, Animal/*methods |
Abstract |
OBJECTIVE: To investigate the effects of early training for jumping by comparing the jumping technique of horses that had received early training with that of horses raised conventionally. ANIMALS: 40 Dutch Warmblood horses. PROCEDURE: The horses were analyzed kinematically during free jumping at 6 months of age. Subsequently, they were allocated into a control group that was raised conventionally and an experimental group that received 30 months of early training starting at 6 months of age. At 4 years of age, after a period of rest in pasture and a short period of training with a rider, both groups were analyzed kinematically during free jumping. Subsequently, both groups started a 1-year intensive training for jumping, and at 5 years of age, they were again analyzed kinematically during free jumping. In addition, the horses competed in a puissance competition to test maximal performance. RESULTS: Whereas there were no differences in jumping technique between experimental and control horses at 6 months of age, at 4 years, the experimental horses jumped in a more effective manner than the control horses; they raised their center of gravity less yet cleared more fences successfully than the control horses. However, at 5 years of age, these differences were not detected. Furthermore, the experimental horses did not perform better than the control horses in the puissance competition. CONCLUSIONS AND CLINICAL RELEVANCE: Specific training for jumping of horses at an early age is unnecessary because the effects on jumping technique and jumping capacity are not permanent. |
Address |
Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, NL-3584 CM Utrecht, The Netherlands |
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0002-9645 |
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PMID:15822585 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
4037 |
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Author |
Hostetter, A.B.; Cantero, M.; Hopkins, W.D. |
Title |
Differential use of vocal and gestural communication by chimpanzees (Pan troglodytes) in response to the attentional status of a human (Homo sapiens) |
Type |
Journal Article |
Year |
2001 |
Publication |
Journal of Comparative Psychology |
Abbreviated Journal |
J. Comp. Psychol. |
Volume |
115 |
Issue |
4 |
Pages |
337-343 |
Keywords |
Animals; *Attention; *Communication Methods, Total; Female; *Gestures; Humans; Male; Motivation; Pan troglodytes/*psychology; Social Environment; Species Specificity; *Vocalization, Animal |
Abstract |
This study examined the communicative behavior of 49 captive chimpanzees (Pan troglodytes), particularly their use of vocalizations, manual gestures, and other auditory- or tactile-based behaviors as a means of gaining an inattentive audience's attention. A human (Homo sapiens) experimenter held a banana while oriented either toward or away from the chimpanzee. The chimpanzees' behavior was recorded for 60 s. Chimpanzees emitted vocalizations faster and were more likely to produce vocalizations as their 1st communicative behavior when a human was oriented away from them. Chimpanzees used manual gestures more frequently and faster when the human was oriented toward them. These results replicate the findings of earlier studies on chimpanzee gestural communication and provide new information about the intentional and functional use of their vocalizations. |
Address |
Department of Psychology, Berry College, USA |
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0735-7036 |
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PMID:11824896 |
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yes |
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Equine Behaviour @ team @ |
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4970 |
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Author |
Scheidhacker, M.; Bender, W.; Vaitl, P. |
Title |
Die Wirksamkeit des therapeutischen Reitens bei der Behandlung chronisch schizophrener Patienten |
Type |
Journal Article |
Year |
1991 |
Publication |
Der Nervenarzt |
Abbreviated Journal |
Nervenarzt |
Volume |
62 |
Issue |
5 |
Pages |
283-287 |
Keywords |
Adaptation, Psychological; Adult; Animals; Attention; Chronic Disease; Female; Follow-Up Studies; *Horses; Humans; Male; Psychiatric Status Rating Scales; Psychotherapy/*methods; Schizophrenia/*rehabilitation; *Schizophrenic Psychology; Self Concept; *Sports |
Abstract |
After describing horse-riding as a facility in managing mentally ill patients, a program for chronic schizophrenic in-patients is presented. Clinical experience with this program and also results of a controlled study are reported. The therapeutic value and slope for horse-riding are discussed in relation to different diagnoses. |
Address |
Bezirkskrankenhaus Haar b. Munchen |
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German |
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Die Wirksamkeit des therapeutischen Reitens bei der Behandlung chronisch schizophrener Patienten. Experimentelle Ergebnisse und klinische Erfahrungen |
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0028-2804 |
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[The effectiveness of therapeutic horseback-riding in the treatment of chronic schizophrenic patients. Experimental results and clinical experiences] |
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no |
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Equine Behaviour @ team @ |
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5067 |
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Author |
Rollot, Y.; Lecuyer, E.; Chateau, H.; Crevier-Denoix, N. |
Title |
Development of a 3D model of the equine distal forelimb and of a GRF shoe for noninvasive determination of in vivo tendon and ligament loads and strains |
Type |
Journal Article |
Year |
2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
Volume |
36 |
Issue |
8 |
Pages |
677-682 |
Keywords |
Animals; Biomechanics; Floors and Floorcoverings; Forelimb/*physiology/ultrasonography; Gait/physiology; Horses/*physiology; Image Processing, Computer-Assisted; Imaging, Three-Dimensional/methods/*veterinary; Ligaments, Articular/*physiology; Locomotion/*physiology; Models, Biological; Shoes; Tendons/*physiology; Toe Joint/physiology/ultrasonography |
Abstract |
REASONS FOR PERFORMING STUDY: As critical locomotion events (e.g. high-speed and impacts during racing, jump landing) may contribute to tendinopathies, in vivo recording of gaits kinematic and dynamic parameters is essential for 3D reconstruction and analysis. OBJECTIVE: To propose a 3D model of the forelimb and a ground reaction force recording shoe (GRF-S) for noninvasively quantifying tendon and ligament loads and strains. METHODS: Bony segments trajectories of forelimbs placed under a power press were recorded using triads of ultrasonic kinematic markers linked to the bones. Compression cycles (from 500-6000 N) were applied for different hoof orientations. Locations of tendon and ligament insertions were recorded with regard to the triads. The GRF-S recorded GRF over the hoof wall and used four 3-axis force sensors sandwiched between a support shoe and the shoe to be tested. RESULTS: Validation of the model by comparing calculated and measured superficial digital flexor tendon strains, and evaluation of the role of proximal interphalangeal joint in straight sesamoidean ligament and oblique sesamoidean ligament strains, were successfully achieved. Objective comparisons of the 3 components of GRF over the hoof for soft and hard grounds could be recorded, where the s.d. of GRF norm was more important on hard ground at walk and trot. CONCLUSIONS: Soft grounds (sand and rubber) dissipate energy by lowering GRF amplitude and diminish bounces and vibrations at impact. At comparable speed, stance phase was longer on soft sand ground. POTENTIAL RELEVANCE: The conjugate use of the GRF-S and the numerical model would help to quantify and analyse ground/shoe combination on comfort, propulsion efficiency or lameness recovery. |
Address |
UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, 7, Avenue du General de Gaulle, 94704 Maisons-Alfort, France |
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0425-1644 |
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PMID:15656495 |
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no |
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Equine Behaviour @ team @ |
Serial |
3769 |
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Author |
Gulotta, M.; Gilmanshin, R.; Buscher, T.C.; Callender, R.H.; Dyer, R.B. |
Title |
Core formation in apomyoglobin: probing the upper reaches of the folding energy landscape |
Type |
Journal Article |
Year |
2001 |
Publication |
Biochemistry |
Abbreviated Journal |
Biochemistry |
Volume |
40 |
Issue |
17 |
Pages |
5137-5143 |
Keywords |
Animals; Apoproteins/*chemistry; Computer Simulation; Horses; Hydrogen-Ion Concentration; Kinetics; Models, Molecular; Myoglobin/*chemistry; *Protein Folding; Protein Structure, Secondary; Protein Structure, Tertiary; Spectrometry, Fluorescence/instrumentation/methods; Thermodynamics; Tryptophan/chemistry |
Abstract |
An acid-destabilized form of apomyoglobin, the so-called E state, consists of a set of heterogeneous structures that are all characterized by a stable hydrophobic core composed of 30-40 residues at the intersection of the A, G, and H helices of the protein, with little other secondary structure and no other tertiary structure. Relaxation kinetics studies were carried out to characterize the dynamics of core melting and formation in this protein. The unfolding and/or refolding response is induced by a laser-induced temperature jump between the folded and unfolded forms of E, and structural changes are monitored using the infrared amide I' absorbance at 1648-1651 cm(-1) that reports on the formation of solvent-protected, native-like helix in the core and by fluorescence emission changes from apomyoglobin's Trp14, a measure of burial of the indole group of this residue. The fluorescence kinetics data are monoexponential with a relaxation time of 14 micros. However, infrared kinetics data are best fit to a biexponential function with relaxation times of 14 and 59 micros. These relaxation times are very fast, close to the limits placed on folding reactions by diffusion. The 14 micros relaxation time is weakly temperature dependent and thus represents a pathway that is energetically downhill. The appearance of this relaxation time in both the fluorescence and infrared measurements indicates that this folding event proceeds by a concomitant formation of compact secondary and tertiary structures. The 59 micros relaxation time is much more strongly temperature dependent and has no fluorescence counterpart, indicating an activated process with a large energy barrier wherein nonspecific hydrophobic interactions between helix A and the G and H helices cause some helix burial but Trp14 remains solvent exposed. These results are best fit by a multiple-pathway kinetic model when U collapses to form the various folded core structures of E. Thus, the results suggest very robust dynamics for core formation involving multiple folding pathways and provide significant insight into the primary processes of protein folding. |
Address |
Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA |
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Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0006-2960 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
PMID:11318635 |
Approved |
no |
Call Number |
Equine Behaviour @ team @ |
Serial |
3789 |
Permanent link to this record |