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Isoelectric focusing of proteins in the pH gradient as a tool for identification of species origin of raw meat
2018
Różycki, Mirosław | Chmurzyńska, Ewa | Bilska-Zając, Ewa | Karamon, Jacek | Cencek, Tomasz
Health, religious, and commercial aspects justify the need for meat species identification. The lack of officially approved methods prompts the undertaking of research on validation of isoelectric focusing of proteins (IEF) for official purposes. Samples were prepared from pigs (Sus scrofa ferus domestica), cattle (Bos taurus), and poultry (Gallus gallus domesticus). Meat mixtures were made by blending 50%, 25%, 10%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.2% meat of other species. Samples were examined on ultrathin polyacrylamide gels with pH 3–9 gradient. The results of the study confirmed the stable and reproducible pattern of meat protein bands. The detection limit of raw meat admixtures from pigs, cattle, and poultry mostly ranged from 2% down to 0.2% (0.2% for poultry). However, the IEF method can be used to detect the addition of pig meat to bovine meat in an amount higher than 3%. At the significant mixture level (i.e at least 5% addition of meat of another species) IEF proves itself with 100% specificity, sensitivity, and accuracy. The achieved detection limits provide a basis for recommending the IEF method for routine tests in laboratories detecting the species origin of meat.
Afficher plus [+] Moins [-]Detection of myxoma virus in the classical form of myxomatosis using an AGID assay: statistical assessment of the assay’s diagnostic performance
2020
Kwit, Ewa | Osiński, Zbigniew | Lavazza, Antonio | Rzeżutka, Artur
The aim of the study was to estimate the diagnostic sensitivity (DSe) and specificity (DSp) of an agar gel immunodiffusion (AGID) assay for detection of myxoma virus (MYXV) in the classical form of myxomatosis and to compare its diagnostic performance to that of molecular methods (IAC-PCR, OIE PCR, and OIE real-time PCR). A panel of MYXV-positive samples of tissue homogenates with low (1 PCR unit – PCRU) and high (3,125 PCRU) virus levels and outbreak samples were used for method comparison studies. The validation parameters of the AGID assay were assessed using statistical methods. The AGID attained DSe of 0.65 (CI₉₅%: 0.53–0.76), DSp of 1.00 (CI₉₅%: 0.40–1.00), and accuracy of 0.67 (CI₉₅%: 0.55–0.76). The assay confirmed its diagnostic usefulness primarily for testing samples containing ≥3,125 PCRU of MYXV DNA. However, in the assaying of samples containing <3,125 PCRU of the virus there was a higher probability of getting false negative results, and only molecular methods showed a 100% sensitivity for samples with low (1 PCRU) virus concentration. The overall concordance of the results between AGID and IAC-PCR was fair (ĸ = 0.40). Full concordance of the results was observed for OIE PCR and OIE real-time PCR when control reference material was analysed. Findings from this study suggest that AGID can be used with some limitations as a screening tool for detection of MYXV infections.
Afficher plus [+] Moins [-]Impact of synthetic canine cerumen on in vitro penetration of auricular skin of dogs by florfenicol, terbinafine, and betamethasone acetate
2018
Ehling, Sarah | Baynes, Ronald E. | Bäumer, Wolfgang
OBJECTIVE To determine the pharmacokinetics of florfenicol, terbinafine, and betamethasone acetate after topical application to canine auricular skin and the influence of synthetic canine cerumen on pharmacokinetics. SAMPLE Auricular skin from 6 euthanized shelter dogs (3 females and 3 neutered males with no visible signs of otitis externa). PROCEDURES Skin adjacent to the external opening of the ear canal was collected and prepared for use in a 2-compartment flow-through diffusion cell system to evaluate penetration of an otic gel containing florfenicol, terbinafine, and betamethasone acetate over a 24-hour period. Radiolabeled 14C-terbinafine hydrochloride and 3H-betamethasone acetate were added to the gel to determine dermal penetration and distribution. Florfenicol absorption was determined by use of high-performance liquid chromatography–UV detection. Additionally, the effect of synthetic canine cerumen on the pharmacokinetics of all compounds was evaluated. RESULTS During the 24-hour experiment, mean ± SD percentage absorption without the presence of synthetic canine cerumen was 0.28 ± 0.09% for 3H-betamethasone acetate, 0.06 ± 0.06% for florfenicol, and 0.06 ± 0.02% for 14C-terbinafine hydrochloride. Absorption profiles revealed no impact of synthetic canine cerumen on skin absorption for all 3 active compounds in the gel or on skin distribution of 3H-betamethasone acetate and 14C-terbinafine hydrochloride. CONCLUSIONS AND CLINICAL RELEVANCE 3H-betamethasone acetate, 14C-terbinafine hydrochloride, and florfenicol were all absorbed in vitro through healthy auricular skin specimens within the first 24 hours after topical application. Synthetic canine cerumen had no impact on dermal absorption in vitro, but it may serve as a temporary reservoir that prolongs the release of topical drugs.
Afficher plus [+] Moins [-]Pharmacokinetics of detomidine following intravenous or oral-transmucosal administration and sedative effects of the oral-transmucosal treatment in dogs
2016
Messenger, Kristen M. | Hopfensperger, Marie | Knych, Heather K. | Papich, Mark G.
OBJECTIVE To determine the pharmacokinetics of detomidine hydrochloride administered IV (as an injectable formulation) or by the oral-transmucosal (OTM) route (as a gel) and assess sedative effects of the OTM treatment in healthy dogs. ANIMALS 12 healthy adult dogs.PROCEDURES In phase 1, detomidine was administered by IV (0.5 mg/m2) or OTM (1 mg/m2) routes to 6 dogs. After a 24-hour washout period, each dog received the alternate treatment. Blood samples were collected for quantification via liquid chromatography with mass spectrometry and pharmacokinetic analysis. In phase 2, 6 dogs received dexmedetomidine IV (0.125 mg/m2) or detomidine gel by OTM administration (0.5 mg/m2), and sedation was measured by a blinded observer using 2 standardized sedation scales while dogs underwent jugular catheter placement. After a l-week washout period, each dog received the alternate treatment. RESULTS Median maximum concentration, time to maximum concentration, and bioavailability for detomidine gel following OTM administration were 7.03 ng/mL, 1.00 hour, and 34.52%, respectively; harmonic mean elimination half-life was 0.63 hours. All dogs were sedated and became laterally recumbent with phase 1 treatments. In phase 2, median global sedation score following OTM administration of detomidine gel was significantly lower (indicating a lesser degree of sedation) than that following IV dexmedetomidine treatment; however, total sedation score during jugular vein catheterization did not differ between treatments. The gel was subjectively easy to administer, and systemic absorption was sufficient for sedation. CONCLUSIONS AND CLINICAL RELEVANCE Detomidine gel administered by the OTM route provided sedation suitable for a short, minimally invasive procedure in healthy dogs.
Afficher plus [+] Moins [-]Agar gel immunodiffusion test for the detection of bovine leukemia virus antibodies: lack of trans-Atlantic standardization
2000
Simard, C. | Richardson, S. | Dixon, P. | Komal, J.
Two agar gel immunodiffusion (AGID) kits for the serodiagnosis of bovine leukemia virus (BLV) were imported from Europe and were compared with North American kits. The BLV AGID kits from North America and from Europe differed significantly. The punches were different, as were the pattern distribution in the agar of the reference and the test sera, resulting in differences in the reading of the immunoprecipitation lines. Based on the testing of 1200 serum samples from cattle, the European kits gave a good correlation with the American kits, as indicated by their respective kappa values. However, the European kits were found to be less sensitive when evaluated against weakly positive samples from field specimens or following a dilution trial. Only 65% and 50% of the weakly positive samples detected by the American kit #1 were detected by the European kits #2 and #3, respectively. The American kit was also capable of detecting BLV antibodies in 45% of strongly positive samples diluted 1/50 in negative sera, while antibodies were detected in only 15% of the samples with the European kit #2 and in none of the samples with the European kit #3. False negatives were also detected with the European kits. Among the false negatives, the degree of expected reactions was weak (European kit #2) or of varying degrees of positivity (European kit #3). Besides the differences in format and performance, the BLV-AGID kits in Europe are evaluated with the National Standard Serum E4 while a proficiency panel composed of a quadruplicate set of 10 reference sera is used in Canada to monitor the kits. Based on the overall observations, we noted a lack of standardization between the BLV-AGID kits used in North America and in Europe.
Afficher plus [+] Moins [-]Antigen expression in cultured oral keratinocytes from dogs
1991
Wilkinson, J.E. | Smith, C.A. | Suter, M.M. | Lewis, R.M.
Oral keratinocytes from dogs were cultured on either collagen gels or artificial matrices at the air-liquid interface, and the expression of keratinocyte antigens and basement membrane components was determined, using various monoclonal and polyclonal antibodies. Keratinocytes grown on collagen gels expressed pemphigus vulgaris, pemphigus foliaceous, and bullous pemphigoid antigens. Diffuse, suprabasal, and superficial keratinocyte membrane differentiation antigens identified by various monoclonal antibodies also were expressed in a pattern identical to that observed in the native tissue. Laminin and type-IV collagen were deposited at the keratinocyte-collagen interface in a patchy distribution. When synthetic matrices were used, the oral keratinocytes differentiated, but to a lesser extent than cells grown on collagen gels. Antigen expression for cells grown on synthetic matrices was similar to that for cells on collagen, except for failure of the keratinocytes on synthetic membranes to express superficial cell antigens and pemphigus foliaceous antigens.
Afficher plus [+] Moins [-]Evaluation of the thermal antinociceptive effects of subcutaneous administration of butorphanol tartrate or butorphanol tartrate in a sustained-release poloxamer 407 gel formulation to orange-winged Amazon parrots (Amazona amazonica)
2020
Laniesse, Delphine | Sanchez-Migallon Guzman, David | Smith, Dale A. | Douglas, Jaime M. | Mosley, Cornelia | Beaufrere, Hugues | Paul-Murphy, Joanne
OBJECTIVE To determine the thermal antinociceptive effects of butorphanol tartrate and butorphanol tartrate in a sustained-release 25% poloxamer 407 (P407) gel formulation (But-P407) in parrots. ANIMALS 13 orange-winged Amazon parrots (Amazona amazonica). PROCEDURES First, butorphanol tartrate (5 mg/kg) or saline (0.9% NaCl) solution was administered IM to birds in a randomized complete crossover design. The temperature prompting a foot withdrawal response to a thermal stimulus (ie, the thermal threshold) was determined 30 minutes before (baseline) and at various points after treatment administration. Second, But-P407 (12.5 mg/kg) or P407 was administered SC in a similar crossover design. Thermal threshold was determined before and at various points after treatment administration. Third, But-P407 (12.5 mg/kg) or saline solution was administered SC and evaluated as in the second trial. Sedation was scored immediately before each time point in all 3 trials. RESULTS In the first trial, a significant increase in thermal threshold was noted 30 minutes after butorphanol tartrate (vs saline solution) administration. No sedation was noted. In the second and third trials, no significant difference was identified between results for But-P407 and those for either control treatment (saline solution or P407). Mild sedation was noted in the second trial following But-P407 administration. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested a small but significant thermal antinociceptive effect of butorphanol tartrate lasting between 30 minutes and 1.5 hours in orange-winged Amazon parrots. No antinociceptive effect of butorphanol tartrate was demonstrated when delivered in P407. Further research is needed to evaluate the potential analgesic effects of But-P407.
Afficher plus [+] Moins [-]Pharmacokinetic evaluation of novel midazolam gel formulations following buccal administration to healthy dogs
2018
Aldawsari, Mohammed F. | Lau, Vivian W. | Babu, Ramapuram J. | Arnold, Robert D. | Platt, Simon R.
OBJECTIVE To determine the physiochemical properties and pharmacokinetics of 3 midazolam gel formulations following buccal administration to dogs. ANIMALS 5 healthy adult hounds. PROCEDURES In phase 1 of a 2-phase study, 2 gel formulations were developed that contained 1% midazolam in a poloxamer 407 (P1) or hydroxypropyl methylcellulose (H1) base and underwent rheological and in vitro release analyses. Each formulation was buccally administered to 5 dogs such that 0.3 mg of midazolam/kg was delivered. Each dog also received midazolam hydrochloride (0.3 mg/kg, IV). There was a 3-day interval between treatments. Blood samples were collected immediately before and at predetermined times for 8 hours after drug administration for determination of plasma midazolam concentration and pharmacokinetic analysis. During phase 2, a gel containing 2% midazolam in a hydroxypropyl methylcellulose base (H2) was developed on the basis of phase 1 results. That gel was buccally administered such that midazolam doses of 0.3 and 0.6 mg/kg were delivered. Each dog also received midazolam (0.3 mg/kg, IV). All posttreatment procedures were the same as those for phase 1. RESULTS The H1 and H2 formulations had lower viscosity, greater bioavailability, and peak plasma midazolam concentrations that were approximately 2-fold as high, compared with those for the P1 formulation. The mean peak plasma midazolam concentration for the H2 formulation was 187.0 and 106.3 ng/mL when the midazolam dose administered was 0.6 and 0.3 mg/kg, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that buccal administration of gel formulations might be a viable alternative for midazolam administration to dogs.
Afficher plus [+] Moins [-]Evaluation of topical ophthalmic ganciclovir gel for the treatment of dogs with experimentally induced ocular canine herpesvirus-1 infection
2018
Ledbetter, Eric C. | Nicklin, Amanda M. | Spertus, Chole B. | Pennington, Matthew R. | Van de Walle, Gerlinde R. | Mohammed, Hussni O.
OBJECTIVE To determine the in vitro half maximal effective concentration (EC50) of ganciclovir for canine herpesvirus-1 (CHV-1) and to evaluate the efficacy of ganciclovir ophthalmic gel in dogs with experimentally induced ocular CHV-1 infection. ANIMALS 10 specific pathogen–free adult Beagles. PROCEDURES Cytotoxicity and EC50 of ganciclovir for CHV-1 were determined during in vitro experiments. During an in vivo experiment, dogs with experimentally induced ocular CHV-1 infections received 1 drop of 0.15% ganciclovir (ganciclovir group; n = 5) or artificial tear (control group; 5) ophthalmic gel in both eyes 5 times daily for 7 days, then 3 times daily for 7 days. For each dog, ophthalmic and confocal microscopic examinations were performed at predetermined times to determine severity of ocular disease and inflammation. Conjunctival swab specimens were collected at predetermined times for PCR assay analysis to determine CHV-1 shedding. RESULTS No in vitro cytotoxic effects were observed for ganciclovir concentrations ≤ 500μM. The EC50 of ganciclovir for CHV-1 was 37.7μM. No adverse effects associated with ganciclovir were observed during the in vivo experiment. Mean ocular disease and inflammation scores for the ganciclovir group were significantly lower than those for the control group. Mean duration of CHV-1 shedding for the ganciclovir group (0.4 days) was significantly shorter than that for the control group (6.2 days). CONCLUSIONS AND CLINICAL RELEVANCE Topical administration of 0.15% ganciclovir ophthalmic gel was well tolerated and effective in decreasing clinical disease scores, ocular tissue inflammation, and duration of viral shedding in dogs with experimentally induced ocular CHV-1 infection.
Afficher plus [+] Moins [-]Analysis of efficacy obtained with a trivalent inactivated Haemophilus parasuis serovars 4, 5, and 12 vaccine and commercial vaccines against Glässer's disease in piglets
2017
Zhao, Z. | Liu, H. | Xue, Y. | Chen, K. | Liu, Z. | Xue, Q. | Wang, C.
The objective of this study was to assess the efficacy of a trivalent inactivated Haemophilus parasuis serovars 4, 5, and 12 vaccine with polymeric adjuvant gel (GEL) and commercial vaccines against Glässer's disease in piglets. Commercial vaccines containing inactivated H. parasuis serovars 4 and 5 (China), inactivated H. parasuis serovars 1 and 6 (Spain), and inactivated H. parasuis serovar 5 (USA) were also evaluated. Our results demonstrated that the trivalent inactivated H. parasuis serovars 4, 5, and 12 vaccine with GEL adjuvant can provide better protection against the 3 most common pathogenic serovars circulating in China than other commercial vaccines tested. Our findings also indicated that inactivated H. parasuis serovars 1 and 6 vaccine cross-protects piglets against H. parasuis serovars 4 and 5; inactivated H. parasuis serovar 5 vaccine cross-protects piglets against H. parasuis serovar 4 challenge; but none of the commercial vaccines tested in this study protected piglets against H. parasuis serovar 12. Our results provide a basis for further identification of common protective antigens that can induce cross-protection against heterogeneous serovars.
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