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61.
Hydroxycinnamic acid amides of serotonin (HCAAS) [caffeoylserotonin (compound 1), p-coumaroylserotonin (compound 2), and feruloylserotonin (compound 3)] are secondary metabolites produced in plants. The aim of this study was to investigate the cytoprotective effects of HCAAS based on intracellular reactive oxygen radical (ROS) generation, lipid peroxidation, protein carbonylation, and phosphorylation of histone H2AX in H2O2 treated-HepG2 and HaCaT cells. We have shown that HCAAS showed various strong antioxidant activities in hydrogen peroxide treated both cell lines, suggesting that these compounds may play as chemotherapeutic agents for preventing or reducing the oxidative stress-induced diseases.  相似文献   
62.
Pain recognition and management in animals has advanced considerably in the last decade and currently animal welfare is receiving increasing public interest. However, the comprehensive assessment of pain has been inadequately addressed in horses and till recently composite pain scales (CPSs) have hardly been validated for use in patients. We investigated the reliability and clinical applicability of a CPS, originally developed under experimental conditions for assessing pain in horses with various acute soft-tissue and orthopedic conditions before and after general anesthesia and/or (non)elective surgery. These clinical cases (n = 94) were scored by means of the CPS twice daily. Horses without painful conditions and horses admitted for nonpainful diagnostic procedures under general anesthesia were compared with those that were admitted with either acute or chronic surgical and nonsurgical painful conditions of both visceral and somatic origin. Scores of observer 1 were compared with observer 2 to study inter-observer reliability. Composite pain scores showed low baseline values in healthy animals with nonpainful conditions and were not affected when general anesthesia was the only intervention. Inter-observer reliability was very high (n = 23 horses; weighted kappa correlation coefficient, κ = 0.81). Horses with painful conditions responding well to analgesic treatment could be discriminated from horses that had to be euthanized on humane grounds because of painful nonresponsive conditions. We found the CPS to be a promising tool that has the potential to provide a good basis for direct day-to-day assessment of pain status in equine patients with various painful conditions in the future.  相似文献   
63.
We previously confirmed that the transgenic rice line, M4, was about 200-fold more resistant to oxyfluorfen than the wild-type (WT) rice in whole-plant bioassays in pots. The transgenic rice line was also cross-resistant to other protoporphyrinogen oxidase (PROTOX)-inhibiting herbicides, acifluorfen, carfentrazone, and oxadiazon. The objectives of this research were to (a) verify the resistance of transgenic rice plants to commercial doses of PROTOX-inhibiting herbicides under paddy field conditions, (b) compare the growth, yield, and grain quality of transgenic and WT rice under weed-free conditions in a paddy field, and (c) determine the responses of transgenic and WT rice plants to chilling and drought stress. In the field, M4 was resistant to PROTOX inhibitors oxyfluorfen, acifluorfen, carfentrazone, pyraflufen, and oxadiazon in transplanted and direct-seeded rice culture. The transgenic and WT plants had similar plant heights and number of tillers. However, the yield of M4 at T4 and T5 generations was 7–8% less than that of WT plants. This was due to reduced number of spikelets per panicle and reduced grain weight. Head rice yield, immature kernels, damaged kernels, palatability, and protein and amylose contents were similar between M4 and WT rice. There was no difference in chilling injury between WT and M4, but M4 was more tolerant to drought stress than WT plants. PROTOX inhibitor-resistant rice is agronomically viable. It will expand the herbicide options in rice production. Follow-up research is required to elucidate the mechanisms underlying the slight yield difference and differential drought response between WT and transgenic rice.  相似文献   
64.
Caffeoylserotonin (CaS) is a serotonin derivative that belongs to the family of phenylpropanoid amides, but has not previously been identified in plants. In this study, pepper fruits challenged with the anthracnose fungus, Colletotrichum gloeosporioides, were found to synthesize CaS, which accumulated at concentrations of up to 2.3 μg/g fresh weight. The induction of CaS was accompanied by the upregulation of both 4-coumarate-CoA ligase (4CL) and serotonin N-hydroxycinnamoyl transferase (SHT) in unripe pepper fruits. However, no induction of SHT and 4CL was observed in ripe pepper fruits consistent with the lower level of CaS production.  相似文献   
65.
1. The effects of post‐brooding temperature (15 to 27 °C), age (42 to 56 d) and dietary nutrient and concentration energy (11.7 to 13.3 MJ/kg for the finisher diet) on the cumulative food intake and body weight responses of broilers were combined in a predictive simulation model, using multiple regression techniques.

2. An economic model of these responses was developed in which the temperature and age at slaughter are optimised, given food and live body weight prices.

3. If a finisher diet of 13.3 MJ ME and 199 g protein/kg costing 150 £/tonne is fed, and provided the grower diet contains 13.5 MJ and 221 g protein/kg, the optimum temperature is 21 to 22 °C for male and female broilers slaughtered at 61 and 54 d respectively with a live body weight value of £0.50/kg.  相似文献   

66.
REASONS FOR PERFORMING STUDY: Studies on hoof balance have, so far, only assessed the effects of strong and relatively unrealistic interventions due to technical limitations of measuring equipment. For the assessment of more subtle interventions, other techniques are necessary. OBJECTIVES: To test a sensitive pressure measurement system during locomotion and to set a standard for further studies by using the system to evaluate the effects of trimming. METHODS: Eighteen horses were measured before and after trimming with an interval of 4 weeks. Trimming was standardised to a straight hoof-pastern axis. The horses trotted over a pressure/force measuring system, with a temporal resolution of 240 Hz and a spatial resolution of 0.39 cm2. RESULTS: The preferred way of landing was lateral, asymmetrical in both front and hind feet. The duration of landing was shorter in forelimbs than in hindlimbs with an equal decreasing trimming effect. Horses had a fixed hoof-unrollment pattern; the centre of pressure (CoP) travelled towards a maximum lateral deviation and returned towards the dorsopalmar/plantar axis of the hoof. Trimming decreased the intra-individual left/right difference in maximum lateral displacement. CONCLUSIONS: The technique used provided easily accurate data to quantify hoof balance characteristics and to measure short-term trimming effects. POTENTIAL RELEVANCE: Determination of CoP patterns has added value in gait analysis and can improve our understanding of the effects of different interventions on hoof balance.  相似文献   
67.
OBJECTIVE: To determine whether differences in jumping technique among horses are consistent at various ages. ANIMALS: 12 Dutch Warmblood horses. PROCEDURE: Kinematics were recorded during free jumps of horses when they were 6 months old (ie, no jumping experience) and 4 years old (ie, the horses had started their training period to become show jumpers). Mean +/- SD height of the horses was 1.40 +/- 0.04 m at 6 months of age and 1.70 +/- 0.05 m at 4 years of age. RESULTS: Strong correlations were found between values from 6-month-old foals and 4-year-old horses for variables such as peak vertical acceleration generated by the hind limbs (r, 0.91), peak rate of change of effective energy generated by the hind limbs (r, 0.71), vertical velocity at takeoff (r, 0.65), vertical displacement of the center of gravity during the airborne phase (r, 0.81), and duration of the airborne phase (r, 0.70). CONCLUSIONS AND CLINICAL RELEVANCE: Although there are substantial anatomic and behavioral changes during the growing period, certain characteristics of jumping technique observed in na?ve 4-year-olds are already detectable when those horses are foals.  相似文献   
68.
Background: In equine laminitis, the deep digital flexor muscle (DDFM) appears to have increased muscle force, but evidence-based confirmation is lacking.

Objectives: The purpose of this study was to test if the DDFM of laminitic equines has an increased muscle force detectable by needle electromyography interference pattern analysis (IPA).

Animals and Methods: The control group included six Royal Dutch Sport horses, three Shetland ponies and one Welsh pony [10 healthy, sound adults weighing 411 ± 217 kg (mean ± SD) and aged 10 ± 5 years]. The laminitic group included three Royal Dutch Sport horses, one Friesian, one Haflinger, one Icelandic horse, one Welsh pony, one miniature Appaloosa and six Shetland ponies (14 adults, weight 310 ± 178 kg, aged 13 ± 6 years) with acute/chronic laminitis. The electromyography IPA measurements included firing rate, turns/second (T), amplitude/turn (M) and M/T ratio. Statistical analysis used a general linear model with outcomes transformed to geometric means.

Results: The firing rate of the total laminitic group was higher than the total control group. This difference was smaller for the ponies compared to the horses; in the horses, the geometric mean difference of the laminitic group was 1.73 [geometric 95% confidence interval (CI) 1.29–2.32], and in the ponies this value was 1.09 (geometric 95% CI 0.82–1.45).

Conclusion and clinical relevance: In human medicine, an increased firing rate is characteristic of increased muscle force. Thus, the increased firing rate of the DDFM in the context of laminitis suggests an elevated muscle force. However, this seems to be only a partial effect as in this study, the unchanged turns/second and amplitude/turn failed to prove the recruitment of larger motor units with larger amplitude motor unit potentials in laminitic equids.  相似文献   

69.
A field survey was performed to study the infection and development of Fusarium langsethiae in the growing season of wheat, barley, oats and triticale under commercial (2009 – 2011) production. Sampling was completed over three years from fields within the counties of Shropshire and Staffordshire in the UK. Plants sampled (from tillering to harvest) were divided into roots, leaves, lower stem, upper stem and inflorescence/head sub-samples depending on the growth stage of the cereal. DNA was extracted and F. langsethiae DNA quantified using real-time PCR. Fusarium mycotoxins HT-2 and T-2 were quantified from head samples at harvest. Three years of data showed oat to contain the highest levels of both F. langsethiae biomass and HT-2?+?T-2 mycotoxins in harvested heads of the cereals studied. The development of F. langsethiae in all three cereals appeared to be similar. Fusarium langsethiae DNA was not detected in the roots and seedlings of all three cereals suggesting F. langsethiae is not a seedling pathogen of cereals. Head infection if it occurs, is at head emergence but before flowering. Seemingly symptomless heads had high levels of F. langsethiae DNA and HT-2?+?T-2, confirming previous suggestions that F. langsethiae is a symptomless pathogen of oats.  相似文献   
70.
Reasons for performing study: Lameness is a highly prevalent condition in horses and the principal cause of removal from athletic activity. In clinical studies to evaluate nonsteroidal anti‐inflammatory drug therapies, force plates are commonly used to assess improvement of lameness objectively. Hypothesis: To use a force plate to determine the optimal dose of a new COX‐2 inhibitor (firocoxib) that will reduce lameness, when administered orally to horses once daily. Methods: Sixty‐four horses that exhibited chronic lameness presumed due to osteoarthritis, including navicular disease, in at least one of the frontlimbs and at a stable level of severity, were included. Horses were treated per os s.i.d. for 7 days as follows: vehicle control, firocoxib at 0.05, 0.1 or 0.25 mg/kg bwt. Force plate analysis of each horse was done for the selected (most) lame frontlimb at trot. Once between Days ?19 and ?4 (initial examination), and again on Day ?2 or ?1 (baseline), pretreatment force plate assessments were performed, and thereafter horses were assessed on Days 0, 2 and 6, approximately 10 h post treatment each time. Peak vertical force (PVF) and lameness grades at initial examination and at baseline, and their change from baseline in the 4 different treatment groups were analysed statistically at a significance level of P<0.05. Results: The PVF results were found to be superior to vehicle control already at Day 0 for 0.25 mg/kg bwt and at Days 2 and 6 for 0.1 and 0.25 mg/kg bwt (P<0.05). Mean clinical lameness for both concentrations decreased >1 grade at Day 6. Conclusions and clinical relevance: With the dosage of 0.25 mg/kg bwt lameness did not improve more than with 0.1 mg/kg bwt. Thus, 0.1 mg/kg bwt s.i.d. was considered to be the effective dose at reducing chronic lameness in horses presumed due to osteoarthritis, including navicular disease.  相似文献   
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