خيارات البحث
النتائج 681 - 690 من 894
Prevalence of Campylobacter species in milk and some dairy products النص الكامل
2016
A. M. El-Kholy a | A. M. S. Meshref | A. A. El-Gedawy | R. M. Esam
Campylobacteriosis is assumed to be mainly a food-borne disease. Also the importance of milk as a source of human Campylobacter enteritis was confirmed by the European Union summary report on food-borne disease outbreaks. Therefore, the present study was undertaken to detect the prevalence of Campylobacters in milk and milk products. A total of 250 samples (100 milk, 50 Domiati cheese, 50 kareish cheese and 50 ice-cream) were collected from the different collection points in El-Minia and Beni-Suef Governorates. The samples were examined by microbiological culture method, and presumptive isolates were further confirmed by genetic amplification (PCR) using specific primers of hippuricase gene.The overall prevalence of Campylobacter species were 13% in raw milk, 52% in kareish cheese, 18% in Domiati cheese and 6% in ice-cream. PCR amplification of hipO gene of isolated C. jejuni from the milk and milk products samples had been shown identical fingerprints with human isolates at 323bp, which indicates the zoonotic hazards of Campylobacter jejuni in Egypt.
اظهر المزيد [+] اقل [-]Characterization of E. coli and Salmonella spp. isolates associated with omphalitis in baby chicks النص الكامل
2016
Azza A. EL-Sawah | AL Hussien M. Dahshan | Soad A. Nasef | El-Shaymaa El-Nahass | Nayel A. I.
Omphalitis is a major cause of increased first week-chick mortality. Omphalitis, navel-yolk sac infection, is a hatchery-born disease, and also known as ‘mushy chick disease’ or ‘navel ill’. It is a common disease of chicks and poults, often artificially hatched chicks, causing high losses in the brooding period, as a bacterium penetrates the porous egg shell. As incubation conditions are suitable for bacterial growth and incubating eggs as well, various bacteria, such as E. coli, staphylococci, Proteus, Clostridium fecali and Pseudomonas may be involved in the yolk sac infection. The present study aimed to determine bacterial causes of omphalitis through isolation and identification of such pathogens. Therefore, samples from 216 yolk sacs were collected from chicks with unabsorbed yolk materials that could even smell putrid. Among those, 196 (90.7%) were positive; 135 (62.5%) harboured single bacterial strains and 61 (28.2%) had mixed infections. The most prevalent single bacterial isolates were E. coli (110 isolates) and P. aeruginosa (11 isolates). Meanwhile, the most predominant mixed bacterial strains were E. coli with Salmonella spp. (16 isolates; 7.4%) and E. coli with P. aeruginosa (13 isolates; 6%). Other mixed infections were found in low percentages. Most E. coli strains were Congo red-positive and non-haemolytic. Different E. coli serogroups were serologically identified including O27 (4 isolates; 20%), O157 (3isolates; 15%), O26 (3 isolates; 15%) and one isolate of each of the following; O78, O6, O125, O44, O15, O115, O25, O168, O112 and O63 (each of 5%). Different Salmonella serogroups were identified including S. cremieu (2 isolates) and one isolate of each of the following S.enteritidis, S. blegdam, S. senftenberg, S. kingston and S. emek.
اظهر المزيد [+] اقل [-]Characterization of antimicrobial resistant bacterial pathogens recovered from cases of bovine mastitis with special reference to Staphylococcus aureus النص الكامل
2016
Hassan W. H. | Hatem M. E. | Elnwary H. A | Sediek S. H.
In the current study, a total of 20 and 78 milk samples were collected from animals showed signs of clinical and subclinical mastitis, for isolation and identification of different causative pathogens in some dairy farms of Beni-Suef Governorate, and for investigation of in vitro sensitivity. The recovered microorganisms were Staphylococcus species (n=79; 80.61%), Enterococcus spp. (n=28; 28.57%), CAMP negative Streptococci, Pseudomonas aeruginosa (n=7; 7.14%), E. coli (n=3; 3.06%) and Proteus vulgaris (n=1; 1.02%). Antibiogram profile for S. aureus showed that the most effective drug was vancomycin and the least was penicillin. Trials were done to detect biofilm production for recovered isolates of S. aureus (n=23) by the use of a phenotypic method (Congo red agar, CRA) and genotypic methods through determination of some biofilm related genes using PCR. All recovered S.aureus isolates were seeded on the CRA media to detect the biofilm forming ability. It has been found that all tested isolates showed a biofilm forming ability either strong (13; 56.52%) or intermediate (10; 43.48%). The detection of some biofilm associated genes (icaA, icaD and bap genes) using polymerase chain reaction revealed that two (10.53%) isolates out of 19 were negative for all tested genes, 16 (84.21%) isolates harbored both icaA and icaD gene, while only one (5.26%) isolate had all tested genes.
اظهر المزيد [+] اقل [-]In vitro effects of cysteine protease inhibitors on Trichomonas foetus–induced cytopathic changes in porcine intestinal epithelial cells النص الكامل
2016
Tolbert, M Katherine | Brand, Mabre D. | Gould, Emily N.
OBJECTIVE To investigate the effects of specific cysteine protease (CP) inhibitors on cytopathic changes to porcine intestinal epithelial cells induced by Tritrichomonas foetus isolated from naturally infected cats. SAMPLE T foetus isolates from 4 naturally infected cats and nontransformed porcine intestinal epithelial cells. PROCEDURES T foetus isolates were treated with or without 0.1 to 1.0mM of the CP inhibitors antipain, cystatin, leupeptin, and chymostatin and the vinyl sulfone inhibitors WRR-483 and K11777. In-gel gelatin zymography was performed to evaluate the effects of these inhibitors on CP activity of T foetus isolates. Each treated or untreated isolate was also cocultured with monolayers of porcine intestinal epithelial cells for 24 hours, and cytopathic effects of T foetus were evaluated by light microscopy and crystal violet spectrophotometry. RESULTS Results of in-gel gelatin zymography suggested an ability of WRR-483, K11777, and cystatin to target specific zones of CP activity of the T foetus isolates. These inhibitors had no effect on T foetus growth, and the cytopathic changes to the intestinal epithelium induced by all 4 T foetus isolates were significantly inhibited. CONCLUSIONS AND CLINICAL RELEVANCE This study revealed that certain protease inhibitors were capable of inhibiting regions of CP activity (which has been suggested to cause intestinal cell damage in cats) in T foetus organisms and of ameliorating T foetus–induced cytopathic changes to porcine intestinal epithelium in vitro. Although additional research is needed, these inhibitors might be useful in the treatment of cats with trichomonosis.
اظهر المزيد [+] اقل [-]Pharmacokinetics of a combination of amikacin sulfate and penicillin G sodium for intravenous regional limb perfusion in adult horses النص الكامل
2016
Nieto, Jorge E. | Trela, Jan | Stanley, Scott D. | Yamout, Sawsan | Snyder, Jack R.
The aim of this study was to determine the pharmacokinetics of amikacin and penicillin G sodium when administered in combination as an intravenous regional limb perfusion (IVRLP) to horses. Seven healthy adult horses underwent an IVRLP in the cephalic vein with 2 g of amikacin sulfate and 10 mill IU of penicillin G sodium diluted to 60 mL in 0.9% saline. A pneumatic tourniquet set at 450 mmHg was left in place for 30 min. Synovial fluid was collected from the metacarpophalangeal joint 35 min and 2, 6, 12, and 24 h after infusion of the antimicrobials. Concentrations of amikacin and penicillin in synovial fluid were quantitated by liquid chromatography tandem-mass spectrometry analysis. Therapeutic concentrations of amikacin and penicillin for equine-susceptible pathogens were achieved in the synovial fluid. Maximum synovial concentrations (Cmax) (mean ± SE) for amikacin and penicillin were 132 ± 33 μg/mL and 8474 ± 5710 ng/mL, respectively. Only 3 horses had detectable levels of penicillin at 6 h and 1 at the 12 h sample. The combination of amikacin with penicillin G sodium via IVDLP resulted in reported therapeutic concentrations of both antibiotics in the synovial fluid. The Cmax:MIC (minimum inhibitory concentration) ratio for amikacin was 8:1 and Time > MIC for penicillin was 6 h. At 24 h, the mean concentration of amikacin was still above 4 μg/mL. Terminal elimination rate constants (T1/2 lambdaz) were 13.6 h and 2.8 h for amikacin and penicillin, respectively. The use of IVDLP with penicillin may therefore not be practical as rapid clearance of penicillin from the synovial fluid requires frequent perfusions to maintain acceptable therapeutic concentrations.
اظهر المزيد [+] اقل [-]Effect of aminocaproic acid on clot strength and clot lysis of canine blood determined by use of an in vitro model of hyperfibrinolysis النص الكامل
2016
Brown, Jamie C. | Brainard, Benjamin M. | Fletcher, Daniel J. | Nie, Ben | Arnold, Robert D. | Schmiedt, Chad W.
OBJECTIVE To determine pharmacodynamic and pharmacokinetic profiles of aminocaproic acid (ACA) by use of a thromboelastography (TEG)-based in vitro model of hyperfibrinolysis and high-performance liquid chromatography–mass spectrometry. ANIMALS 5 healthy adult dogs. PROCEDURES A single dose of injectable ACA (20, 50, or 100 mg/kg) or an ACA tablet (approximately 100 mg/kg) was administered orally. Blood samples were collected at 0, 15, 30, 45, 60, 90, 120, and 240 minutes after ACA administration for pharmacokinetic analysis. Samples were obtained at 0, 60, and 240 minutes for pharmacodynamic analysis by use of a TEG model of hyperfibrinolysis. RESULTS No adverse effects were detected. In the hyperfibrinolysis model, after all doses, a significantly higher TEG maximum amplitude (clot strength), compared with baseline, was detected at 60 and 240 minutes. Additionally, the percentage of fibrinolysis was reduced from the baseline value at 60 and 240 minutes, with the greatest reduction at 60 minutes. At 240 minutes, there was significantly less fibrinolysis for the 100 mg/kg dose than the 20 mg/kg dose. Maximum plasma ACA concentration was dose dependent. There was no significant difference in pharmacokinetic parameters between 100 mg/kg formulations. CONCLUSIONS AND CLINICAL RELEVANCE In an in vitro model of hyperfibrinolysis, ACA inhibited fibrinolysis at all doses tested. At 240 minutes after administration, the 100 mg/kg dose inhibited fibrinolysis more effectively than did the 20 mg/kg dose. Thus, ACA may be useful for in vivo prevention of fibrinolysis in dogs. IMPACT FOR HUMAN MEDICINE These data may improve research models of hyperfibrinolytic diseases.
اظهر المزيد [+] اقل [-]Development of a double-monoclonal antibody sandwich ELISA: Tool for chicken interferon-γ detection ex vivo النص الكامل
2016
Dai, Hua | Xu, Zheng-zhong | Wang, Meiling | Chen, Jun-hua | Chen, Xiang | Pan, Zhi-ming | Jiao, Xin-an
The aim of the present work was to develop reagents to set up a chicken interferon-γ (ChIFN-γ) assay. Four monoclonal antibodies (mAbs) specific for ChIFN-γ were generated to establish sandwich ELISA based on 2 different mAbs. To improve the detection sensitivity of ChIFN-γ, a double-monoclonal antibody sandwich ELISA was developed using mAb 3E5 as capture antibody and biotinylated mAb 3E3 as a detection reagent. The results revealed that this ELISA has high sensitivity, allowing for the detection of 125 to 500 pg/mL of recombinant ChIFN-γ, and also has an excellent capacity for detecting native ChIFN-γ. This ELISA was then used to detect ChIFN-γ level in chickens immunized with a Newcastle disease virus (NDV) vaccine, the immunized chicken splenocytes were stimulated by NDV F protein as recall antigen. From our results, it appears that the sensitivity range of this sandwich ELISA test is adequate to measure the ex vivo release of ChIFN-γ.
اظهر المزيد [+] اقل [-]Effects of ketamine and lidocaine in combination on the sevoflurane minimum alveolar concentration in alpacas النص الكامل
2016
Querioz-Williams, Patricia | Doherty, Thomas J. | Da Cunha, Anderson F. | Leonardi, Claudia
This study investigated the effects of ketamine and lidocaine in combination on the minimum alveolar concentration of sevoflurane (MACSEVO) in alpacas. Eight healthy, intact male, adult alpacas were studied on 2 separate occasions. Anesthesia was induced with SEVO, and baseline MAC (MACB) determination began 45 min after induction. After MACB determination, alpacas were randomly given either an intravenous (IV) loading dose (LD) and infusion of saline or a loading dose [ketamine = 0.5 mg/kg body weight (BW); lidocaine = 2 mg/kg BW] and an infusion of ketamine (25 μg/kg BW per minute) in combination with lidocaine (50 μg/kg BW per minute), and MACSEVO was re-determined (MACT). Quality of recovery, time-to-extubation, and time-to-standing, were also evaluated. Mean MACB was 1.88% ± 0.13% and 1.89% ± 0.14% for the saline and ketamine + lidocaine groups, respectively. Ketamine and lidocaine administration decreased (P < 0.05) MACB by 57% and mean MACT was 0.83% ± 0.10%. Saline administration did not change MACB. Time to determine MACB and MACT was not significantly different between the treatments. The quality of recovery, time-to-extubation, and time-to-standing, were not different between groups. The infusion of ketamine combined with lidocaine significantly decreased MACSEVO by 57% and did not adversely affect time-to-standing or quality of recovery.
اظهر المزيد [+] اقل [-]Evaluation of the minimum infectious dose of porcine epidemic diarrhea virus in virus-inoculated feed النص الكامل
2016
Schumacher, Loni L. | Woodworth, Jason C. | Jones, Cassandra K. | Chen, Qi | Zhang, Jianqiang | Gauger, Phillip C. | Stark, Charles R. | Main, Rodger G. | Hesse, Richard A. | Tokach, Mike D. | Dritz, Steve S.
OBJECTIVE To determine the minimum infectious dose of porcine epidemic diarrhea virus (PEDV) in virus-inoculated feed. ANIMALS 30 crossbred 10-day-old pigs. PROCEDURES Tissue culture PEDV was diluted to form 8 serial 10-fold dilutions. An aliquot of stock virus (5.6 × 105 TCID50/mL) and each serial PEDV dilution were mixed into 4.5-kg batches of feed to create 9 PEDV-inoculated feed doses; 1 virus-negative dose of culture medium in feed was also created. Pigs were challenge exposed via oral administration of PEDV-inoculated feed, and fecal swab specimens were collected. All pigs were euthanized 7 days after challenge exposure; fresh tissues were collected and used for PCR assay, histologic examination, and immunohistochemical analysis. RESULTS The PCR cycle threshold (Ct) decreased by approximately 10 when PEDV was added to feed, compared with results for equivalent PEDV diluted in tissue culture medium. Pigs became infected with PEDV when challenge exposed with the 4 highest concentrations (lowest concentration to cause infection, 5.6 × 10(1) TCID50/g; Ct = 27 in tissue culture medium and 37 in feed). CONCLUSIONS AND CLINICAL RELEVANCE In this study, PEDV in feed with detectable Ct values of 27 to 37 was infective. The Ct was 37 for the lowest infective PEDV dose in feed, which may be above the limit of detection established for PEDV PCR assays used by some diagnostic laboratories. Overall, results indicated 5.6 × 10(1) TCID50/g was the minimum PEDV dose in feed that can lead to infection in 10-day-old pigs under the conditions of this study.
اظهر المزيد [+] اقل [-]In vitro and in vivo assessment of platelet function in healthy dogs during administration of a low-dose aspirin regimen النص الكامل
2016
Haines, Jillian M. | Thomason, John M. | Seage, Eileen C. | Wills, Robert W. | Bulla, Camilo | Lunsford, Kari V. | Mackin, Andrew J.
OBJECTIVE To assess the in vitro and in vivo platelet function of healthy dogs during administration of a low-dose aspirin regimen. ANIMALS 16 dogs. PROCEDURES Dogs received aspirin (1 mg/kg, PO, q 24 h) for 7 days. Blood and urine samples were collected before (day 1; baseline) and on days 3 and 7 of the low-dose aspirin regimen. Platelet function was evaluated by use of turbidimetric and conventional impedance aggregometry, multiple-electrode impedance aggregometry, a platelet function analyzer (PFA), and determination of urine 11-dehydro-thromboxane B2 concentration. Turbidimetric aggregometry results were compared with the results obtained by the other 4 methods. Fourteen days after cessation of aspirin, platelet-rich plasma was incubated with acetylsalicylic acid and platelet function was assessed by turbidimetric aggregometry to determine whether this technique could accurately identify dogs that responded to the low-dose aspirin regimen. RESULTS Of the 16 dogs, 13 had turbidimetric and conventional impedance aggregometry results that were decreased by > 25% from baseline on days 3 and 7, and 4 and 7 dogs had PFA closure times > 300 seconds on days 3 and 7, respectively. The median urine 11-dehydro-thromboxane B2 concentration–to–creatinine concentration ratio decreased by 49% between days 1 and 7. Turbidimetric aggregometry results were correlated with conventional impedance aggregometry results. There was poor agreement between the turbidimetric aggregometry and PFA results. The multiple-electrode impedance aggregometry protocol failed to reliably detect aspirin-induced platelet dysfunction. In vitro incubation of platelet-rich plasma with acetylsalicylic acid followed by turbidimetric aggregometry did not predict whether dogs responded to the low-dose aspirin regimen. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the response to a low-dose aspirin regimen varied among healthy dogs.
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