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101.
Gene and protein expression as well as catalytic activity of cytochrome P450 (CYP) 3A were studied in the nasal olfactory and respiratory mucosa and the tracheal mucosa of the horse. We also examined the activity of NADPH cytochrome P450 reductase (NADPH P450 reductase), the amount of cytochrome b(5) and the total CYP content in these tissues. Comparative values for the above were obtained using liver as a control. The CYP3A related catalytic activity in the tissues of the upper airways was considerably higher than in the liver. The CYP3A gene and protein expression, on the other hand, was higher in the liver than in the upper airway tissues. Thus, the pattern of CYP3A metabolic activity does not correlate with the CYP3A gene and protein expression. Our results showed that the activity of NADPH P450 reductase and the level of cytochrome b(5) in the relation to the gene and protein expression of CYP3A were higher in the tissues of the upper airways than in the liver. It is concluded that CYP3A related metabolism in horse is not solely dependent on the expression of the enzyme but also on adequate levels of NADPH P450 reductase and cytochrome b(5). 相似文献
102.
S S Pérez-Garnelo M Oter C Borque C Talavera M Delclaux E Martínez-Nevado A T Palasz J De la Fuente 《Journal of zoo and wildlife medicine》2006,37(2):116-125
Basic characteristics of European bison (Bison bonasus) semen were described and the efficacies of two extenders-Triladyl, containing egg yolk, and a synthetic extender, containing soybean lipids-were tested for semen cryopreservation. Seven ejaculates were collected by electroejaculation from a 10-yr-old, European bison bull. Each ejaculate was diluted at 37 degrees C to a final concentration of 200 x 10(6) sperm/ml with Triladyl or the synthetic extender. Extended semen samples were frozen according to a standard bull semen freezing protocol. After 2 wk of storage, one straw from each extender and ejaculate was thawed, and postthaw quality was evaluated by individual sperm motility and movement rate, numbers of sperm morphologic abnormalities and intact acrosomes, functional integrity of the sperm membranes determined by hypoosmotic swelling test (HOST), viability (live-dead, eosin-nigrosin stain), and a heterologous in vitro sperm penetration assay (SPA). A total of 600 in vitro-matured bovine oocytes were inseminated with 1 X 10(6) spermatozoa of Holstein semen frozen-thawed in Triladyl (control) or of European bison semen frozen in Triladyl or the synthetic extender. Nuclear status of the oocytes was determined after 18 h of sperm-oocyte coincubation. Extender had no effect on any evaluated parameters of semen after dilution and cooling (4 hr at 5 degrees C) or in postthaw individual motility, quality of movement, and sperm morphology. However, significantly (P < 0.05) higher numbers of spermatozoa with intact acrosomes, intact membranes (HOST), and viable sperm (P < 0.01) were in semen frozen in Triladyl than in the synthetic extender. Mean values for heterologous SPA for bull (control) and for bison semen frozen in the synthetic extender were very much alike-63.3+/-10.6% and 63.1 +/- 15.9%, respectively; bison semen frozen in Triladyl was lower, 43.0+/-24.2% but not significantly different. Cumulative results from a variety of viability assays of diluted/cooled and frozen-thawed semen, including the heterologous SPA, suggest that European bison semen can be successfully frozen in both extenders tested in this study. 相似文献
103.
Kirschvink N Leemans J Delvaux F Snaps F Marlin D Sparkes A Clercx C Gustin P 《Veterinary journal (London, England : 1997)》2006,172(3):446-454
The objective of this study was to establish a reference base for respiratory variables (respiratory rate [R(R)], inspiratory and expiratory time [T(i) and T(e)], peak inspiratory and expiratory pseudoflow [PIF and PEF], tidal volume [V(T)], minute ventilation [V(E)] and enhanced pause [Penh]) of healthy cats by use of barometric whole body plethysmography (BWBP). Eighteen healthy European cats (10 male, 8 female) were studied from the age of 3 to 13 months in order to assess growth- and gender-related changes of BWBP variables. Chest radiographs and bronchoalveolar lavage cytology were performed to confirm pulmonary health status. Diurnal changes were investigated every 2 h over a period of 24 h when the cats were adult. V(T), V(E), PIF and PEF significantly increased during somatic growth and were higher in males than in females, whereas R(R), T(i), T(e), T(e)/T(i) ratio, PEF/PIF ratio and Penh remained unchanged and were not affected by gender. When measured over 24 h, Penh, T(e) and T(i) were significantly increased in the early morning hours (04:00 h), whereas R(R), PIF and PEF were decreased at that time. This study provides reference values of BWBP variables for healthy male and female cats and indicates when circadian changes might be observed. 相似文献
104.
García-Fernández RA Pérez-Martínez C Alvarez JE Navarrete AJ García-Iglesias MJ 《Veterinary dermatology》2006,17(1):36-44
Epidermal morphogenesis was studied in vivo following prenatal exposure to retinoic acid (RA). In pregnant mice, a single oral dose of RA on day 11.5 of gestation failed to induce histological changes in fetal epidermal development except in epidermal thickness. Epidermal thickness increased from 16.5 days post-coitum (dpc) onwards, and temporal and spatial epidermal modifications in keratins K5 and K14 related to proliferative activity of keratinocytes were observed. An RA effect on cell proliferation was supported by a statistically significant increase in the number of epidermal S-phase cells, containing BrdU-incorporated DNA in RA-exposed mice compared with nonexposed animals. The prolonged in utero action of RA on epidermal proliferative activity in fetuses and newborns suggests a long-term RA effect that may play a role on the development and evolution of diseases in adult skin. 相似文献
105.
Séguin MJ Friendship RM Kirkwood RN Zanella AJ Widowski TM 《Journal of animal science》2006,84(5):1227-1237
The objective of this study was to determine the effects of boar presence on aggression, shoulder scratches, and salivary cortisol in group-housed sows during the period after mixing, which is when dominance hierarchies are formed. A total of 225 York-shire sows were used. Five groups of 15 sows were each exposed to 1 of 3 levels of boar presence (n = 15): physical (boar in pen with sows; 2.15 m2 per sow), fenceline (boar housed adjacent to sows; 2.3 m2 per sow), or control (no boar in the room; 2.3 m2 per sow). The experiment was divided into 2 phases. In phase 1, behavioral measurements were taken for 48 h after mixing and boar introduction. In phase 2, behavioral measurements were taken beginning on d 6 after mixing and included 24 h before and 48 h after boar removal. In phases 1 and 2, shoulder scratches were scored 24 h before and 24 h after mixing and boar removal, respectively. Saliva samples were collected each morning (0600 to 0700) and afternoon (1600 to 1700) during both phases. Frequencies of intersow aggressive contact (bite, body knock, and head knock) and threats as well as frequencies and durations of fighting bouts were determined from video recordings during daily feeding (49.6 +/- 1.4 min) and nonfeeding (21 +/- 0.2 h) periods. During phase 1, boar presence did not affect the frequency of threats during either the feeding or nonfeeding periods. Control groups had fewer aggressive contacts at feeding during the 25- to 48-h period compared with the fenceline groups (P = 0.01). Total duration of fighting and average fighting bout duration were unaffected by treatment. However, the number of fights occurring during feeding 25 to 48 h postmixing was lower in the physical groups than in the fenceline groups (P = 0.023); measures for the control groups were intermediate. Physical sows also received fewer shoulder scratches postmixing than did control sows (P = 0.048). After mixing, physical sows showed greater morning (P = 0.08) and afternoon (6 h postmixing, P = 0.01; 32 h postmixing, P = 0.08) salivary cortisol concentrations compared with fenceline sows, although they were only numerically greater than those for control sows. During phase 2, removing the boar did not increase fighting among sows or affect shoulder scratches or salivary cortisol concentrations. The presence of a boar was minimally effective at reducing fighting and scratches during the postmixing period, and sows showed a greater stress response in the presence of a boar. 相似文献
106.
107.
Thais Borges Lessa Rafael Cardoso Carvalho André Luis Rezende Franciolli Lilian Jesus de Oliveira RodrigoSilvadaNunes Barreto David Feder Fabiana Fernandes Bressan Maria Angélica Miglino Carlos Eduardo Ambrósio 《Acta veterinaria Scandinavica》2012,54(1):73
Background
The diaphragm is the major respiratory muscle affected by Duchenne muscular dystrophy (DMD) and is responsible for causing 80% of deaths. The use of mechanical forces that act on the body or intermittent pressure on the airways improves the quality of life of patients but does not prevent the progression of respiratory failure. Thus, diseases that require tissue repair, such as DMD, represent a group of pathologies that have great potential for cell therapy. The application of stem cells directly into the diaphragm instead of systemic application can reduce cell migration to other affected areas and increase the chances of muscle reorganisation. The mdx mouse is a suitable animal model for this research because its diaphragmatic phenotype is similar to human DMD. Therefore, the aim of this study was to assess the potential cell implantation in the diaphragm muscle after the xenotransplantation of stem cells.Methods
A total of 9 mice, including 3 control BALB/Cmice, 3 5-month-old mdx mice without stem cell injections and 3 mdx mice injected with stem cells, were used. The animals injected with stem cells underwent laparoscopy so that stem cells from GFP-labelled rabbit olfactory epithelium could be locally injected into the diaphragm muscle. After 8 days, all animals were euthanised, and the diaphragm muscle was dissected and subjected to histological and immunohistochemical analyses.Results
Both the fresh diaphragm tissue and immunohistochemical analyses showed immunopositive GFP labelling of some of the cells and immunonegativity of myoblast bundles. In the histological analysis, we observed a reduction in the inflammatory infiltrate as well as the presence of a few peripheral nuclei and myoblast bundles.Conclusion
We were able to implant stem cells into the diaphragm via local injection, which promoted moderate muscle reorganisation. The presence of myoblast bundles cannot be attributed to stem cell incorporation because there was no immunopositive labelling in this structure. It is believed that the formation of the bundles may have been stimulated by cellular signalling mechanisms that have not yet been elucidated. 相似文献108.
Hultén C Grönlund U Hirvonen J Tulamo RM Suominen MM Marhaug G Forsberg M 《Equine veterinary journal》2002,34(7):699-704
Despite the importance of noninfectious joint diseases in equine medicine, little is known about the acute phase response which may be elicited if the local inflammatory process of noninfectious arthritis is sufficiently strong, Therefore the aim of this study was to monitor the systemic inflammatory response during experimentally-induced noninfectious arthritis by studying the dynamics in serum of the acute phase proteins serum amyloid A (SAA), haptoglobin, fibrinogen and alpha2-globulins. Twenty-four Standardbred horses, age 3-7 years, found healthy on thorough clinical, radiological, haematological and serum biochemical examination, were injected aseptically into the right midcarpal joint with amphotericin B. Blood samples were drawn before induction of arthritis (0 h), and at 8, 16, 24, 36 and 48 h postinduction and then on Days 3, 4, 5 and 15 postinduction. All horses developed lameness with joint effusion and joint heat as well as increased respiratory rate, heart rate and body temperature. The lameness started to decline after 24-36 h and, in most animals, systemic signs disappeared on Day 2 postinjection. The concentration of the acute phase proteins increased following induction of arthritis. The SAA concentrations were higher than baseline concentrations from 16 h postinduction and were maximal at 36-48 h (227 times baseline concentration). The haptoglobin concentrations were higher than baseline concentrations from 24 h and were maximal at 48-96 h (1.14 times baseline concentration). The maximal concentrations of fibrinogen were seen between 36-72 h postinjection and increased on average 0.87 times from baseline concentrations. The fibrinogen concentrations were higher than baseline concentrations from 24 h postinjection. Alpha2-globulins concentrations showed a minor increase and increased 0.55 times from baseline concentrations. The markers had returned to baseline concentrations by Day 15. Our results demonstrate that amphotericin B-induced arthritis in a single joint gives rise to a systemic acute phase response measurable as increased concentrations in serum SAA, haptoglobin, fibrinogen and alpha2-globulins during the first 2 weeks of the condition and, thereby, that such an increase need not be indicative of infectious arthritis. Further research should be aimed at determining whether chronic noninfectious arthritis in the horse gives rise to increased acute phase protein concentrations in serum. 相似文献
109.
110.
The weight of internal organs (swimbladder, kidney, liver, spleen) in relation to the body weight was studied in common carp fingerlings divided into three groups on the basis of swimbladder appearance and microscopic examination of the kidney. The fish had been collected from different Hungarian fish farms at the time when swimbladder inflammation (SBI) usually occurs (in July and August). The first group comprised fish with severe signs of SBI and massive renal sphaerosporosis, the second group consisted of fish with milder swimbladder changes and/or kidney infection by a low number of Sphaerospora renicola, while the third group was constituted by infection-free common carp fry. Statistical analysis of swimbladder, kidney, liver and spleen weight in relation to the body weight revealed that in the infected groups the internal organs were substantially enlarged. This suggests that in common carp fry with SBI the swimbladder changes are accompanied by reno-, hepato- and splenomegaly. 相似文献