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ARTs in wild felid conservation programmes in Poland and in the world Texto completo
2019
Kochan, Joanna | Niżański, Wojciech | Moreira, Nei | Cubas, Zalmir Silvino | Nowak, Agnieszka | Prochowska, Sylwia | Partyka, Agnieszka | Młodawska, Wiesława | Skotnicki, Józef
ARTs in wild felid conservation programmes in Poland and in the world Texto completo
2019
Kochan, Joanna | Niżański, Wojciech | Moreira, Nei | Cubas, Zalmir Silvino | Nowak, Agnieszka | Prochowska, Sylwia | Partyka, Agnieszka | Młodawska, Wiesława | Skotnicki, Józef
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.
Mostrar más [+] Menos [-]ARTs in wild felid conservation programmes in Poland and in the world Texto completo
Joanna Kochan | Wojciech Niżański | Nei Moreira | Zalmir Silvino Cubas | Agnieszka Nowak | Sylwia Prochowska | Agnieszka Partyka | Wiesława Młodawska | Józef Skotnicki
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented. | wild felids; assisted reproduction technology; conservation; biodiversity | 140 | 457-464 | 3
Mostrar más [+] Menos [-]ARTs in wild felid conservation programmes in Poland and in the world Texto completo
2019
Kochan Joanna | Niżański Wojciech | Moreira Nei | Cubas Zalmir Silvino | Nowak Agnieszka | Prochowska Sylwia | Partyka Agnieszka | Młodawska Wiesława | Skotnicki Józef
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.
Mostrar más [+] Menos [-]Effects of tiletamine-xylazine-tramadol combination and its specific antagonist on AMPK in the brain of rats Texto completo
2019
Ma, Ning | Li, Xin | Wang, Hong-bin | Gao, Li | Xiao, Jian-hua
Effects of tiletamine-xylazine-tramadol combination and its specific antagonist on AMPK in the brain of rats Texto completo
2019
Ma, Ning | Li, Xin | Wang, Hong-bin | Gao, Li | Xiao, Jian-hua
Introduction: Tiletamine-xylazine-tramadol (XFM) has few side effects and can provide good sedation and analgesia. Adenosine 5’-monophosphate-activated protein kinase (AMPK) can attenuate trigeminal neuralgia. The study aimed to investigate the effects of XFM and its specific antagonist on AMPK in different regions of the brain. Material and Methods: A model of XFM in the rat was established. A total of 72 Sprague Dawley (SD) rats were randomly divided into three equally sized groups: XFM anaesthesia (M group), antagonist (W group), and XFM with antagonist interactive groups (MW group). Eighteen SD rats were in the control group and were injected intraperitoneally with saline (C group). The rats were sacrificed and the cerebral cortex, cerebellum, hippocampus, thalamus, and brain stem were immediately separated, in order to detect AMPKα mRNA expression by quantitative PCR. Results: XFM was able to increase the mRNA expression of AMPKα1 and AMPKα2 in all brain regions, and the antagonist caused the opposite effect, although the effects of XFM could not be completely reversed in some areas. Conclusion: XFM can influence the expression of AMPK in the central nervous system of the rat, which can provide a reference for the future development of anaesthetics for animals.
Mostrar más [+] Menos [-]Effects of tiletamine-xylazine-tramadol combination and its specific antagonist on AMPK in the brain of rats Texto completo
2019
Ma Ning | Li Xin | Wang Hong-bin | Gao Li | Xiao Jian-hua
Introduction: Tiletamine-xylazine-tramadol (XFM) has few side effects and can provide good sedation and analgesia. Adenosine 5’-monophosphate-activated protein kinase (AMPK) can attenuate trigeminal neuralgia. The study aimed to investigate the effects of XFM and its specific antagonist on AMPK in different regions of the brain. Material and Methods: A model of XFM in the rat was established. A total of 72 Sprague Dawley (SD) rats were randomly divided into three equally sized groups: XFM anaesthesia (M group), antagonist (W group), and XFM with antagonist interactive groups (MW group). Eighteen SD rats were in the control group and were injected intraperitoneally with saline (C group). The rats were sacrificed and the cerebral cortex, cerebellum, hippocampus, thalamus, and brain stem were immediately separated, in order to detect AMPKα mRNA expression by quantitative PCR. Results: XFM was able to increase the mRNA expression of AMPKα1 and AMPKα2 in all brain regions, and the antagonist caused the opposite effect, although the effects of XFM could not be completely reversed in some areas. Conclusion: XFM can influence the expression of AMPK in the central nervous system of the rat, which can provide a reference for the future development of anaesthetics for animals.
Mostrar más [+] Menos [-]Screening of early diagnostic markers of gentamicin-induced acute kidney injury in canines Texto completo
2019
Zheng, Jia-San | Jing-Nie, | Zhu, Ting-Ting | Ruan, Hong-Ri | Xue, Wei | Rui-Wu,
Screening of early diagnostic markers of gentamicin-induced acute kidney injury in canines Texto completo
2019
Zheng, Jia-San | Jing-Nie, | Zhu, Ting-Ting | Ruan, Hong-Ri | Xue, Wei | Rui-Wu,
The value of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (Kim-1), and liver-type fatty acid binding protein (L-FABP) was assessed in early diagnosis of gentamicin-induced acute kidney injury (AKI) in dogs. Subcutaneous gentamicin injection in 16 healthy adult beagles made the AKI model. Blood was sampled every 6 h to detect NGAL, Kim-1, L-FABP, and serum creatinine (SCr) concentrations. Kidney tissue of two dogs was taken before the injection, as soon as SCr was elevated (78 μmol/L), and when it had risen to 1.5 times the baseline, and haematoxylin-eosin staining and transmission electron microscopy (TEM) were used to observe changes. NGAL, Kim-1, and SCr levels were significantly increased (P < 0.05) at 18, 30, and 78 h post injection, but L-FABP concentration was not associated with renal injury. At the earliest SCr elevation stage, findings were mild oedema, degeneration, and vacuolisation in renal tubular epithelial cells in pathology, and mild cytoplasmic and mitochondrial oedema in TEM. At this time point, NGAL and Kim-1 concentrations were significantly increased (P < 0.05), indicating that these two molecules biomark early kidney injury in dogs. Using receiver operating characteristic curve analysis, their warning levels were > 25.31 ng/mL and > 48.52 pg/mL. Plasma NGAL and Kim-1 above warning levels are early indicators of gentamicin-induced AKI in dogs.
Mostrar más [+] Menos [-]Screening of early diagnostic markers of gentamicin-induced acute kidney injury in canines Texto completo
2019
Zheng Jia-San | Jing-Nie | Zhu Ting-Ting | Ruan Hong-Ri | Xue-Wei | Rui-Wu
The value of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (Kim-1), and liver-type fatty acid binding protein (L-FABP) was assessed in early diagnosis of gentamicin-induced acute kidney injury (AKI) in dogs.
Mostrar más [+] Menos [-]Pituitary-testicular axis dysfunction in methimazole-induced hypothyroidism in rats Texto completo
2019
Gołyński, Marcin | Metyk, Michał | Szkodziak, Piotr | Lutnicki, Krzysztof | Kalisz, Grzegorz | Szczepanik, Marcin | Wilkołek, Piotr | Dobrowolski, Piotr
Pituitary-testicular axis dysfunction in methimazole-induced hypothyroidism in rats Texto completo
2019
Gołyński, Marcin | Metyk, Michał | Szkodziak, Piotr | Lutnicki, Krzysztof | Kalisz, Grzegorz | Szczepanik, Marcin | Wilkołek, Piotr | Dobrowolski, Piotr
Introduction: Thyroid hormones play a major role in the regulation of testicular maturation and growth and in the control of Sertoli and Leydig cell functions in adulthood. When naturally occurring, hypothyroidism causes male hypogonadotropic hypogonadism and Sertoli cell function disorders, but when iatrogenic and methimazole-induced its influence on the pituitary-testicular axis function with respect to Sertoli cells is poorly known. Material and Methods: Male adult Wistar rats (n = 14) were divided into two groups: E – taking methimazole orally for 60 days, and C – control animals. After 60 d, the concentrations in serum of testosterone, follicle-stimulating and luteinising hormones, and inhibins A and B were measured. Testicles were examined morphologically: the apoptotic Sertoli cell percentage (ASC%) and number of these cells functional per tubular mm² (FSCN/Tmm²) were calculated. Results: In group E, inhibin A was higher while inhibin B was lower than in group C. ASC% was higher and FSCN/Tmm² lower in group E than in group C. Conclusion: A specific modulation of Sertoli cell function in the course of methimazole-induced hypothyroidism leads to a simultaneous concentration increase in inhibin A and decrease in B. Inhibin A might share responsibility for pituitary-testicular axis dysfunction and hypogonadotropic hypogonadism in this model of hypothyroidism.
Mostrar más [+] Menos [-]Pituitary-testicular axis dysfunction in methimazole-induced hypothyroidism in rats Texto completo
2019
Gołyński Marcin | Metyk Michał | Szkodziak Piotr | Lutnicki Krzysztof | Kalisz Grzegorz | Szczepanik Marcin | Wilkołek Piotr | Dobrowolski Piotr
Introduction: Thyroid hormones play a major role in the regulation of testicular maturation and growth and in the control of Sertoli and Leydig cell functions in adulthood. When naturally occurring, hypothyroidism causes male hypogonadotropic hypogonadism and Sertoli cell function disorders, but when iatrogenic and methimazole-induced its influence on the pituitary-testicular axis function with respect to Sertoli cells is poorly known.
Mostrar más [+] Menos [-]Effect of simvastatin on thrombopoiesis in porcine bone marrow Texto completo
2019
Snarska, Anna | Wysocka, Dominika | Rytel, Liliana
Effect of simvastatin on thrombopoiesis in porcine bone marrow Texto completo
2019
Snarska, Anna | Wysocka, Dominika | Rytel, Liliana
Introduction: Statins are pharmacological agents commonly used to lower serum cholesterol level. The aim of the experiment was to investigate the effect of the statin simvastatin on thrombopoiesis in the porcine model because it is the closest to the human one regarding physiological and genetic similarities. Material and Methods: The study was conducted on a group of 32 pigs randomly divided into two equal groups: control and experimental. The pigs were treated for 28 and 56 days with simvastatin in a dose of 40 mg per day per animal. Cytological evaluation of bone marrow smears was performed to assess the average number of all types of cells during thrombopoiesis as was analysis of haematological parameters to assess PLT and MPV. Results: During the course of the experiment statistically significant changes in the number of promegakaryocytes were observed. Other parameters also showed some fluctuations during the study. However, these changes were not statistically significant. Conclusion: The obtained results clearly indicate a toxic influence of simvastatin on the process of thrombopoiesis and prove that statins reduce mean platelet volume, thus affecting the process of clot formation through the period of administration in a duration-dependent manner.
Mostrar más [+] Menos [-]Effect of simvastatin on thrombopoiesis in porcine bone marrow Texto completo
2019
Snarska Anna | Wysocka Dominika | Rytel Liliana
Introduction: Statins are pharmacological agents commonly used to lower serum cholesterol level. The aim of the experiment was to investigate the effect of the statin simvastatin on thrombopoiesis in the porcine model because it is the closest to the human one regarding physiological and genetic similarities.
Mostrar más [+] Menos [-]Ex vivo evaluation of arytenoid corniculectomy, compared with three other airway interventions, performed on cadaveric equine larynges with simulated recurrent laryngeal neuropathy Texto completo
2019
OBJECTIVE To compare laryngeal impedance, in terms of air flow and pressure, following arytenoid corniculectomy (COR) versus 3 other airway interventions (left-sided laryngoplasty with ipsilateral ventriculocordectomy [LLP], LLP combined with COR [LLPCOR], and partial arytenoidectomy [PA]) performed on cadaveric equine larynges with simulated left recurrent laryngeal neuropathy (RLN) and to determine whether relative laryngeal collapse correlated with the interventions performed. SAMPLE 28 cadaveric equine larynges. PROCEDURES Each larynx in states of simulated left RLN alone and with airway interventions in the order LLP, LLPCOR, COR, and PA was evaluated in a box model construct that replicated upper airway flow mechanics consistent with peak exercise in horses. Results for impedance, calculated from airflow and pressure changes, were compared between states for each larynx. Multivariable mixed-effects analysis controlling for repeated measures within larynx was performed to calculate the predicted mean impedance for each state. RESULTS Results indicated that tracheal adapter diameter, individual larynx properties, airway intervention, and relative laryngeal collapse affected laryngeal impedance. The LLP and LLPCOR interventions had the lowest impedance, whereas the COR and PA interventions did not differ substantially from the simulated left RLN state. Residual intraclass correlation of the model was 27.6 %. CONCLUSIONS AND CLINICAL RELEVANCE Although impedance was higher for the simulated left RLN with the COR intervention state than with the LLP intervention state, given the clinical success of PA for treating RLN in horses and the similar results for the COR and PA intervention states in the present study, the use of COR warrants further investigation. The residual interclass correlation suggested that individual laryngeal variation affected impedance and may have a clinical effect.
Mostrar más [+] Menos [-]Evaluation of atipamezole as a treatment for dexmedetomidine-induced cardiovascular depression in anesthetized cats Texto completo
2019
Zatroch, Kathryn K. | Sakai, Daniel M. | Parry, Stephen | Campoy, Luis | Martin-Flores, Manuel
OBJECTIVE To evaluate the cardiovascular effects of atipamezole administered at half the volume or the same volume as dexmedetomidine to isoflurane-anesthetized cats. ANIMALS 6 adult (1 to 2 years old) domestic shorthair cats (body weight, 3 to 6 kg). PROCEDURES Each cat was anesthetized with isoflurane and rocuronium 3 times; there was a 1-week washout period between successive anesthetic procedures. For each anesthetic procedure, dexmedetomidine (5 μg/kg) was administered IV. Five minutes after dexmedetomidine was administered, atipamezole (25 or 50 μg/kg) or saline (0.9% NaCl) solution was administered IM. Pulse rate, mean arterial blood pressure (MAP), cardiac output (CO), and systemic vascular resistance (SVR) were measured during anesthesia before dexmedetomidine administration (baseline), after dexmedetomidine administration, and 15, 30, 60, and 120 minutes after administration of atipamezole or saline solution. Pulse rate and MAP were also recorded when MAP was at its lowest value. Hemodynamic variables were compared among treatments at baseline, after dexmedetomidine administration, and after administration of atipamezole or saline solution. Effects of treatment and time on all variables were assessed with mixed-effects models. RESULTS Both doses of atipamezole resulted in a significantly lower MAP than did saline solution. Pulse rate, CO, and SVR were not significantly different among treatments after atipamezole or saline solution were administered. CONCLUSIONS AND CLINICAL RELEVANCE Atipamezole administered IM at half the volume or the same volume as dexmedetomidine was ineffective at increasing pulse rate or CO in anesthetized cats that received dexmedetomidine. However, atipamezole caused short-lasting but severe arterial hypotension.
Mostrar más [+] Menos [-]Histologic assessment of age-related changes in the temporomandibular joints of horses Texto completo
2019
Smyth, Travis T. | Allen, Andrew L. | Carmalt, James L.
OBJECTIVE To describe histologic changes in the temporomandibular joints (TMJs) of horses of various ages. SAMPLE 22 TMJs from cadavers of 11 horses. PROCEDURES Horses were categorized into 3 age groups (group 1, 2 to 10 years old [n = 3]; group 2, 11 to 20 years old [3]; and group 3, > 20 years old [5]). Each TMJ was sectioned into 5-mm slices, preserved in formalin, decalcified in formic acid, and routinely processed for histologic analysis. Joints were systematically assessed by use of previously described methods. Multilevel mixed-effects models were used to examine the data. RESULTS The number of changes was significantly fewer and degree of changes was significantly less within the TMJs of group 1 horses, compared with those of group 3 horses. Comparison among groups revealed that the combination of temporal and mandibular scores for group 1 was significantly lower than for groups 2 or 3. Disk score did not differ significantly between groups 1 and 2, but disk scores of groups 1 and 2 were significantly lower than the disk score of group 3. CONCLUSIONS AND CLINICAL RELEVANCE The assessed lesions were associated with osteoarthritis, and they accumulated in the TMJs as horses aged. In the absence of signs of pain manifested as changes in mastication, behavior, or performance, it would be difficult to determine the point at which accrued pathological changes represented the onset of clinically important osteoarthritis of the TMJs.
Mostrar más [+] Menos [-]An assessment of mechanical properties and screw push-out for two 3.5-mm pearl-type locking plate systems Texto completo
2019
Tremolada, Giovanni | Taggart, Ryan | Lewis, Daniel D. | Palmer, Ross H. | Lambrechts, Nicolaas E.
OBJECTIVE To compare mechanical properties (stiffness, yield load, failure load, and deformation at failure) of 2 pearl-type locking plate system (PLS) constructs (PLS 1 and PLS 2) in a simulated fracture gap model and to compare screw push-out forces of the 2 PLSs with and without plate contouring. SAMPLE 40 PLS constructs. PROCEDURES Mechanical properties of uncontoured PLS 1 (n = 8) and PLS 2 (8) constructs were evaluated in synthetic bone-plate models under axial compression. Screw push-out forces were evaluated in 6 uncontoured and 6 contoured PLSs of each type. Variables of interest were compared between PLS groups and between contoured and uncontoured plates by statistical methods. RESULTS Yield and failure loads were higher in the PLS 1 group than in the PLS 2 group, but stiffness did not differ significantly between groups. All constructs failed by plate bending, with greater deformation in the PLS 2 group. Push-out force to screw-plate uncoupling was higher in the PLS 2 group than in the PLS 1 group for uncontoured and contoured plates. Locking mechanism failure of PLS 1 specimens was through screw-thread stripping. The PLS 2 specimens failed by node deformation followed by screwhead stripping. CONCLUSIONS AND CLINICAL RELEVANCE Distinct mechanical differences were identified between the 2 PLSs. The clinical relevance of these differences is unknown. Further research including cyclic fatigue testing is needed to reveal more clinically pertinent information.
Mostrar más [+] Menos [-]Evaluation of glomerular filtration rate estimation by means of plasma clearance of iohexol in domestic rabbits (Oryctolagus cuniculus) Texto completo
2019
Lippi, Ilaria | Perondi, Francesca | Petrini, Daniele | La Fortuna, Maria Cristina | Luci, Giacomo | Intorre, Luigi | Guidi, Grazia | Meucci, Valentina
OBJECTIVE To evaluate glomerular filtration rate (GFR) estimation by means of plasma clearance of iohexol (IOX) in domestic rabbits and to assess accuracy of limited-sampling models for GFR estimation. ANIMALS 6 healthy domestic rabbits (Oryctolagus cuniculus). PROCEDURES Each rabbit received IOX (64.7 mg/kg [0.1 mL/kg], IV), and blood samples were collected at predetermined times before and after administration. Plasma IOX concentration was determined by high-performance liquid chromatography. The pharmacokinetics of IOX was determined by a noncompartmental method. For each rabbit, plasma clearance of IOX was determined by dividing the total IOX dose administered by the area under the concentration-time curve indexed to the subject's body weight. The GFR estimated from the plasma IOX concentration at 6 sampling times (referent model) was compared with that estimated from the plasma IOX concentration at 5 (model A), 4 (model B), and 3 (models C, D, and E) sampling times (limited-sampling models). RESULTS Mean ± SD GFR was 4.41 ± 1.10 mL/min/kg for the referent model and did not differ significantly from the GFR estimated by any of the limited-sampling models. The GFR bias magnitude relative to the referent model was smallest for model D in which GFR was estimated from plasma IOX concentrations at 5, 15, and 90 minutes after IOX administration. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that plasma clearance of IOX was a safe, reliable, accurate, and clinically feasible method to estimate GFR in domestic rabbits. Further research is necessary to refine the method.
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