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Ahrendt, L.P.; Christensen, J.W.; Ladewig, J. |
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Title |
The ability of horses to learn an instrumental task through social observation |
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Year |
2012 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
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Volume |
139 |
Issue |
1 |
Pages |
105-113 |
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Keywords |
Horse; Social learning; Social interaction; Instrumental task; Investigative behaviour; Aggression |
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Abstract |
The ability of horses to learn through social observation may ease the implementation of new management systems, because the use of automatic feeders etc. by naive horses could be facilitated by observation of experienced horses. However, previous studies found no documentation for observational learning abilities in horses. This study aimed to investigate the ability of horses to learn an instrumental task from a familiar conspecific when social interaction was allowed during the demonstration. Two similar experiments were performed. In the first experiment, Observer horses (n=11) participated in ten successive demonstrations, where a trained Demonstrator opened an operant device by pushing a sliding lid aside with the muzzle in order to obtain a food reward. Immediately after the demonstrations the Observer horses were given the opportunity to operate the device alone. Control horses (n=11) were aware that the device contained food but were presented to the operant device without demonstration of the task. The learning criterion was at least two openings. Accomplishment of and latency to accomplish the learning criterion, and investigative behaviour towards the operant device were recorded. Five Observers and one Control, out of the eleven horses in each treatment group, accomplished the learning criterion. Even though this presents a high odds ratio (OR) in favour of the Observer treatment (OR=7.6), there was no significant difference between the treatment groups (P=0.15). Analysis of investigative behaviour showed, however, that the demonstrations increased the motivation of the Observer horses to investigate the device. Subsequently, a similar experiment was performed in a practical setting with 44 test horses (mixed age, gender and breed). We used the same operant device and the same number and type of demonstrations, although the horses were held on a loose rope to minimise aggression. In this second experiment, six of 23 Observer horses and five of 21 Control horses learned the instrumental task, representing no influence of the demonstration. Thus, this study did not demonstrate an ability of horses to learn an instrumental task through observation. |
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0168-1591 |
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Equine Behaviour @ team @ S0168-1591(12)00087-1 |
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5773 |
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Skandakumar, S.; Stodulski, G.; Hau, J. |
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Title |
Salivary IgA: a Possible Stress Marker In Dogs |
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Abstract |
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Year |
1995 |
Publication |
Animal Welfare |
Abbreviated Journal |
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Volume |
4 |
Issue |
4 |
Pages |
339-350 |
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Keywords |
Animal Welfare; Behaviour; Cortisol; Dog; Salivary Iga (S-Iga); Stress; Well-Being |
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Abstract |
Stress in humans has been reported to be associated with a decrease in the salivary immunoglobulin A (s-IgA) levels enabling the possible use of s-IgA to assess stress. Prolonged stress, if reliably assessed in a non-invasive manner, may be used to assess animal welfare. This study analysed groups of dogs undergoing physical and temperamental training and s-IgA levels were measured by rocket immunoelectrophoresis in prospective samples. Behavioural assessment was carried out and cortisol levels in saliva were measured by ELISA. A significant negative correlation (P < 0.007) between the logarithmic cortisol concentrations and s-IgA levels in saliva was recorded. The behavioural assessment of the dogs agreed well with the biochemical markers. It is concluded that IgA levels in saliva may be a useful marker of dog well-being and that stress results in decreased s-IgA levels. |
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Equine Behaviour @ team @ |
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5964 |
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Author |
Nicol, C.J.; Adachi, M.; Akiyama, T.E.; Gonzalez, F.J. |
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Title |
PPARgamma in endothelial cells influences high fat diet-induced hypertension |
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Journal Article |
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Year |
2005 |
Publication |
American journal of hypertension : journal of the American Society of Hypertension |
Abbreviated Journal |
Am J Hypertens |
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Volume |
18 |
Issue |
4 Pt 1 |
Pages |
549-556 |
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Keywords |
Administration, Oral; Animals; Antihypertensive Agents/pharmacology; Blood Pressure/drug effects; Diabetes Mellitus, Type 2/physiopathology; Dietary Fats/*administration & dosage/pharmacology; Dose-Response Relationship, Drug; Endothelial Cells/*metabolism; Female; Heart Rate/drug effects; Hypertension/*etiology; Ligands; Male; Mice; Mice, Knockout; PPAR gamma/*metabolism; Sodium Chloride/administration & dosage/pharmacology; Thiazolidinediones/pharmacology |
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BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands improve human hypertension. However, the mechanism and site of this effect remains unknown, confounded by PPARgamma expression in many cell types, including endothelial cells (ECs). METHODS: To evaluate the vascular role of PPARgamma we used a conditional null mouse model. Specific disruption of PPARgamma in ECs was created by crossing Tie2-Cre+ transgenic (T2T+) and PPARgamma-floxed (fl/fl) mice to generate PPARgamma (fl/fl)T2T+ (PPARgamma E-null) mice. Conscious 8- to 12-week-old congenic PPARgamma (fl/fl)Cre- (wild type) and PPARgamma E-null mice were examined for changes in systolic blood pressure (BP) and heart rate (HR), untreated, after 2 months of salt-loading (drinking water), and after treatment for 3 months with high fat (HF) diet alone or supplemented during the last 2 weeks with rosiglitazone (3 mg/kg/d). RESULTS: Untreated PPARgamma E-nulls were phenotypically indistinguishable from wild-type littermates. However, compared to similarly treated wild types, HF-treated PPARgamma E-nulls had significantly elevated systolic BP not seen after normal diet or salt-loading. Despite sex-dependent baseline differences, salt-loaded and HF-treated PPARgamma E-nulls of either sex had significantly elevated HR versus wild types. Interestingly, rosiglitazone improved serum insulin levels, but not HF diet-induced hypertension, in PPARgamma E-null mice. CONCLUSIONS: These results suggest that PPARgamma in ECs not only is an important regulator of hypertension and HR under stressed conditions mimicking those arising in type 2 diabetics, but also mediates the antihypertensive effects of rosiglitazone. These data add evidence supporting a beneficial role for PPARgamma-specific ligands in the treatment of hypertension, and suggest therapeutic strategies targeting ECs may prove useful. |
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Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
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0895-7061 |
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PMID:15831367 |
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Call Number |
refbase @ user @ |
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69 |
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Hertsch, B.; Becker, C. |
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[Occurrence of aseptic necrosis of the palmar and plantar ligament in the horse--a contribution to the differentiation of sesamoid bone diseases] |
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Journal Article |
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1986 |
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DTW. Deutsche tierarztliche Wochenschrift |
Abbreviated Journal |
Dtsch Tierarztl Wochenschr |
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Volume |
93 |
Issue |
6 |
Pages |
263-266 |
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Keywords |
Animals; Diagnosis, Differential; Horse Diseases/*pathology; Horses; Ligaments, Articular/*pathology; Osteonecrosis/*pathology; Sesamoid Bones/*pathology |
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German |
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Zum Vorkommen der aseptischen Nekrose im Ligamentum palmare bzw. plantare beim Pferd--ein Beitrag zur Differenzierung der Gleichbeinerkrankungen |
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0341-6593 |
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PMID:3527654 |
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Call Number |
refbase @ user @ |
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150 |
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Author |
Rollot, Y.; Lecuyer, E.; Chateau, H.; Crevier-Denoix, N. |
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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 |
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Journal Article |
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Year |
2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
36 |
Issue |
8 |
Pages |
677-682 |
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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 |
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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. |
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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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Equine Behaviour @ team @ |
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3769 |
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Author |
Abbruzzetti, S.; Viappiani, C.; Sinibaldi, F.; Santucci, R. |
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Title |
Kinetics of histidine dissociation from the heme Fe(III) in N-fragment (residues 1-56) of cytochrome c |
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Journal Article |
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2004 |
Publication |
The Protein Journal |
Abbreviated Journal |
Protein J |
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23 |
Issue |
8 |
Pages |
519-527 |
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Keywords |
Animals; Cytochromes c/*chemistry; Enzyme Activation; Histidine/*chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Lasers; Ligands; Peptide Mapping; Photolysis; Spectrophotometry |
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We have here investigated the dissociation kinetics of the His side chains axially ligated to the heme-iron in the ferric (1-56 residues) N-fragment of horse cyt c. The ligand deligation induced by acidic pH-jump occurs as a biexponential process with different pre-exponential factors, consistent with a structural heterogeneity in solution and the presence of two differently coordinated species. In analogy with GuHCl-denatured cyt c, our data indicate the presence in solution of two ferric forms of the N-fragment characterized by bis-His coordination, as summarized in the following scheme: His18-Fe(III)-His26 <==> His18-Fe(III)-His33. We have found that the pre-exponential factors depend on the extent of the pH-jump. This may be correlated with the different pKa values shown by His26 and His33; due to steric factors, His26 binds to the heme-Fe(III) less strongly than His33, as recently shown by studies on denatured cyt c. Interestingly, the two lifetimes are affected by temperature but not by the extent of the pH-jump. The lower pKa for the deligation reaction required the use of an improved laser pH-jump setup, capable of inducing changes in H+ concentration as large as 1 mM after the end of the laser pulse. For the ferric N-fragment, close activation entropy values have been determined for the two histidines coordinated to the iron; this result significantly differs from that for GuHCl-denatured cyt c, where largely different values of activation entropy were calculated. This underlines the role played by the missing segment (residues 57-104) peptide chain in discriminating deligation of the “nonnative” His from the sixth coordination position of the metal. |
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Dipartimento di Fisica, Universita degli Studi di Parma, Parco Area delle Scienze 7/A 43100 Parma, Italy |
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1572-3887 |
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PMID:15648974 |
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Equine Behaviour @ team @ |
Serial |
3770 |
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Author |
Kasashima, Y.; Takahashi, T.; Smith, R.K.W.; Goodship, A.E.; Kuwano, A.; Ueno, T.; Hirano, S. |
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Title |
Prevalence of superficial digital flexor tendonitis and suspensory desmitis in Japanese Thoroughbred flat racehorses in 1999 |
Type |
Journal Article |
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Year |
2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
36 |
Issue |
4 |
Pages |
346-350 |
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Keywords |
Age Factors; Animals; Female; Forelimb; Hindlimb; Horse Diseases/*epidemiology/etiology; Horses; Inflammation/epidemiology/etiology/*veterinary; Japan/epidemiology; Ligaments/injuries/*pathology; Male; Musculoskeletal Diseases/epidemiology/etiology/veterinary; *Physical Conditioning, Animal; Prevalence; Retrospective Studies; Risk Factors; Sex Factors; Sports; Tendinopathy/epidemiology/etiology/*veterinary; Tendon Injuries/epidemiology/etiology/*veterinary |
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Abstract |
REASONS FOR PERFORMING STUDY: Overstrain injuries to the superficial digital flexor tendon (SDFT) and suspensory ligament (SI) are among the most common musculoskeletal injuries which contribute to the considerable wastage of racing Thoroughbreds. Many epidemiological studies have demonstrated the prevalence of and risk factors for tendon injury when racing but have not included those injuries sustained during training. However, since tendon injury during training is seen commonly in clinical practice, it is appropriate to determine the overall prevalence of tendon injury sustained during both training and racing. OBJECTIVE: To determine the prevalence of overstrain injury to the SDFT and SL during training and racing among Thoroughbred flat racehorses in Japan in 1999. METHODS: A retrospective study was performed using a sample population of 10,262 Thoroughbred racehorses. The medical information database of Thoroughbred racehorses registered by the Japan Racing Association (JRA) in 1999 was analysed for SDFT and SL overstrain injury diagnosed by a veterinarian employed by JRA during training and racing. Jump racehorses were excluded from this study. RESULTS: The prevalence of forelimb SDFT tendonitis and SL desmitis was 11.1% (1130 cases) and 3.61% (370 cases) of the population, respectively. In the hindlimb, there were 0.06% (6 cases) and 0.14% (14 cases), respectively. Risks of SDF tendonitis in the forelimb in 3-year-olds or older horses were significantly higher than in 2-year-olds. In contrast, the risk of SL desmitis in the forelimb at age 3 and 4 years was 2.23 and 2.11 times higher, respectively, than in 2-year-olds, but this increased to 5.07 times in those age > or = 5 years. Entire males were at greater risk in comparison to females and geldings. CONCLUSIONS: The results suggest that the prevalence of SDF tendonitis and SL desmitis in the forelimb was associated with the horse's age and sex. The prevalence of SL desmitis increased further with age compared with SDF tendonitis, possibly reflecting a more rapid accumulation of degeneration in this structure. POTENTIAL RELEVANCE: The age-related risk demonstrated in this study provides further support that overstrain injuries are associated with accumulated degeneration. These data provide a valuable resource for further research into the aetiology of tendon injury in the racehorse. |
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Equine Research Institute, Japan Racing Association, 321-4, Tokami-cho, Utsunomiya-shi, Tochigi, 320-0856, Japan |
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0425-1644 |
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Notes |
PMID:15163043 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3775 |
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Author |
Hirota, S.; Suzuki, M.; Watanabe, Y. |
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Title |
Hydrophobic effect of trityrosine on heme ligand exchange during folding of cytochrome c |
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Journal Article |
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Year |
2004 |
Publication |
Biochemical and Biophysical Research Communications |
Abbreviated Journal |
Biochem Biophys Res Commun |
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Volume |
314 |
Issue |
2 |
Pages |
452-458 |
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Keywords |
Amino Acids/chemistry; Animals; Cytochromes c/*chemistry; Heme/*chemistry; Histidine/chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium/chemistry; Peptides/chemistry; Protein Folding; Spectrophotometry; Spectrum Analysis, Raman; Tyrosine/*analogs & derivatives/*chemistry |
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Abstract |
Effect of a hydrophobic peptide on folding of oxidized cytochrome c (cyt c) is studied with trityrosine. Folding of cyt c was initiated by pH jump from 2.3 (acid-unfolded) to 4.2 (folded). The Soret band of the 2-ms transient absorption spectrum during folding decreased its intensity and red-shifted from 397 to 400 nm by interaction with trityrosine, whereas tyrosinol caused no significant effect. The change in the transient absorption spectrum by interaction with trityrosine was similar to that obtained with 100 mM imidazole, which showed that the population of the intermediate His/His coordinated species increased during folding of cyt c by interaction with trityrosine. The absorption change was biphasic, the fast phase (82+/-9s(-1)) corresponding to the transition from the His/H(2)O to the His/Met coordinated species, whereas the slow phase (24+/-3s(-1)) from His/His to His/Met. By addition of trityrosine, the relative ratio of the slow phase increased, due to increase of the His/His species at the initial stage of folding. According to the resonance Raman spectra of cyt c, the high-spin 6-coordinate and low-spin 6-coordinate species were dominated at pH 2.3 and 4.2, respectively, and these species were not affected by addition of trityrosine. These results demonstrated that the His/His species increased by interaction with trityrosine at the initial stage of cyt c folding, whereas the heme coordination structure was not affected by trityrosine when the protein was completely unfolded or folded. Hydrophobic peptides thus may be useful to study the effects of hydrophobic interactions on protein folding. |
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Address |
Department of Physical Chemistry, Kyoto Pharmaceutical University, Yamashina-ku, 607-8414 Kyoto, Japan. hirota@mb.kyoto-phu.ac.jp |
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0006-291X |
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PMID:14733927 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3777 |
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Author |
Meershoek, L.S.; Schamhardt, H.C.; Roepstorff, L.; Johnston, C. |
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Title |
Forelimb tendon loading during jump landings and the influence of fence height |
Type |
Journal Article |
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Year |
2001 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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Volume |
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Issue |
33 |
Pages |
6-10 |
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Keywords |
Animals; Biomechanics; Forelimb/injuries/physiology; Horses/injuries/*physiology; Lameness, Animal/etiology; Ligaments, Articular/*physiology; Locomotion/*physiology; Physical Conditioning, Animal; Tendon Injuries/complications/physiopathology/veterinary; Tendons/*physiology; Weight-Bearing/physiology |
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Abstract |
Lameness in athletic horses is often caused by forelimb tendon injuries, especially in the interosseus tendon (TI) and superficial digital flexor tendon (SDF), but also in the accessory ligament (AL) of the deep digital flexor tendon (DDF). In an attempt to explain the aetiology of these injuries, the present study investigated the loading of the tendons during landing after a jump. In jumping horses, the highest forces can be expected in the trailing limb during landing. Therefore, landing kinematics and ground reaction forces of the trailing forelimb were measured from 6 horses jumping single fences with low to medium heights of 0.80, 1.00 and 1.20 m. The tendon forces were calculated using inverse dynamics and an in vitro model of the lower forelimb. Calculated peak forces in the TI, SDF and DDF + AL during landing were 15.8, 13.9 and 11.7 kN respectively. The relative loading of the tendons (landing forces compared with failure forces determined in a separate study) increased from DDF to TI to SDF and was very high in SDF. This explains the low injury incidence of the DDF and the high injury incidence of the SDF. Fence height substantially influenced SDF forces, whereas it hardly influenced TI forces and did not influence AL strain. Reduction of fence height might therefore limit the risks for SDF injuries, but not for TI and AL injuries. |
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Department of Veterinary Anatomy and Physiology, Institute for Fundamental and Clinical Human Movement Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands |
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PMID:11721571 |
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Call Number |
Equine Behaviour @ team @ |
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3786 |
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Author |
Abbruzzetti, S.; Viappiani, C.; Small, J.R.; Libertini, L.J.; Small, E.W. |
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Title |
Kinetics of histidine deligation from the heme in GuHCl-unfolded Fe(III) cytochrome C studied by a laser-induced pH-jump technique |
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Journal Article |
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2001 |
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Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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123 |
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27 |
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6649-6653 |
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Animals; *Bacterial Proteins; Cytochrome c Group/*chemistry; Guanidine/*chemistry; Heme/*chemistry; Histidine/*chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; *Lasers; Ligands; Protein Folding |
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Abstract |
We have developed an instrumental setup that uses transient absorption to monitor protein folding/unfolding processes following a laser-induced, ultrafast release of protons from o-nitrobenzaldehyde. The resulting increase in [H(+)], which can be more than 100 microM, is complete within a few nanoseconds. The increase in [H(+)] lowers the pH of the solution from neutrality to approximately 4 at the highest laser pulse energy used. Protein structural rearrangements can be followed by transient absorption, with kinetic monitoring over a broad time range (approximately 10 ns to 500 ms). Using this pH-jump/transient absorption technique, we have examined the dissociation kinetics of non-native axial heme ligands (either histidine His26 or His33) in GuHCl-unfolded Fe(III) cytochrome c (cyt c). Deligation of the non-native ligands following the acidic pH-jump occurs as a biexponential process with different pre-exponential factors. The pre-exponential factors markedly depend on the extent of the pH-jump, as expected from differences in the pK(a) values of His26 and His33. The two lifetimes were found to depend on temperature but were not functions of either the magnitude of the pH-jump or the pre-pulse pH of the solution. The activation energies of the deligation processes support the suggestion that GuHCl-unfolded cyt c structures with non-native histidine axial ligands represent kinetic traps in unfolding. |
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Dipartimento di Fisica, Universita di Parma, Istituto Nazionale per la Fisica della Materia, 43100 Parma, Italy |
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English |
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0002-7863 |
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PMID:11439052 |
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Equine Behaviour @ team @ |
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3788 |
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