@article{ahmmed_reynolds_hamada_regmi_bozkurt_2021, title={Novel 3D-printed Electrodes for Implantable Biopotential Monitoring}, ISSN={["1558-4615"]}, url={http://dx.doi.org/10.1109/embc46164.2021.9630055}, DOI={10.1109/EMBC46164.2021.9630055}, abstractNote={A major bottleneck in the manufacturing process of a medical implant capable of biopotential measurements is the design and assembly of a conductive electrode interface. This paper presents the use of a novel 3D-printing process to integrate conductive metal surfaces on a low-temperature co-fired ceramic base to be deployed as electrodes for electrocardiography (ECG) implants for small animals. In order to fit the ECG sensing system within the size of an injectable microchip implant, the electronics along with a pin-type lithium-ion battery are inserted into a cylindrical glass tube with both ends sealed by these 3D printed composite electrode discs using biomedical epoxy. In the scope of this paper, we present a proof-of-concept in vivo experiment for recording ECG from an avian animal model under local anesthesia to verify the electrode performance. Simultaneous recording with a commercial device validated the measurements, demonstrating promising accuracy in heart rate and breathing rate monitoring. This novel technology could open avenues for the mass manufacturing of miniaturized ECG implants.Clinical relevance— A novel manufacturing process and an implantable system are presented for continuous physiological monitoring of animals to be used by veterinarians, animal scientists, and biomedical researchers with potential future applications in human health monitoring.}, journal={2021 43RD ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY (EMBC)}, publisher={IEEE}, author={Ahmmed, Parvez and Reynolds, James and Hamada, Shu and Regmi, Prafulla and Bozkurt, Alper}, year={2021}, pages={7120–7123} }
 @article{jones_gast_regmi_ward_anderson_karcher_2020, title={Pooling of Laying Hen Environmental Swabs and Efficacy of Salmonella Detection}, volume={83}, ISSN={["1944-9097"]}, DOI={10.4315/JFP-19-467}, abstractNote={Environmental testing for Salmonella Enteritidis is required for U.S. shell egg producers with ≥3,000 hens on a farm. The egg producer assumes all costs for the mandatory testing. According to the U.S. Food and Drug Administration (FDA) Egg Rule, either manure scraper or drag swabs can be collected according to published guidelines and requirements. The present study was undertaken to determine the efficacy of Salmonella detection with one-, two-, and four-swab pools of either manure scraper or drag swabs. Resistant isolates of Salmonella serovars Enteritidis (1,000 ppm of streptomycin), Heidelberg (200 ppm of nalidixic acid [NA]), Typhimurium (200 ppm of NA), and Kentucky (200 ppm of NA) were utilized. Low (approximately 8.4 CFU) and high (approximately 84 CFU) levels of inocula were introduced onto a single swab within a pool. Single flocks from each conventional cage (manure scraper swabs) and cage-free barn (drag swabs) were monitored throughout the study at the ages required under the FDA Egg Rule. The highest and most consistent recovery of inoculum was found in single swab samples. For low dose inocula, recovery of isolates was low from single manure scraper swabs (57.9 to 29.2%) and decreased as more swabs were added to the pool. Recovery of isolates from manure scraper swabs was higher for high dose inocula, although Salmonella Heidelberg was outcompeted by the naturally occurring flora and had the lowest rate of recovery among the isolates tested. One- and two-swab pools of drag swabs had similar rates of recovery at both low and high doses for Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Typhimurium. When Salmonella Enteritidis and Salmonella Kentucky were combined in an inoculum, Salmonella Enteritidis was recovered at a much higher rate than was Salmonella Kentucky for all types of swabs and doses of inocula. Pooling of two drag swabs allowed for similar detection of low and high dose Salmonella, but the pooling of manure scraper swabs decreased detection of low dose Salmonella.}, number={6}, journal={JOURNAL OF FOOD PROTECTION}, author={Jones, Deana R. and Gast, Richard K. and Regmi, Prafulla and Ward, Garrett E. and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2020}, month={Jun}, pages={943–950} }
 @article{gast_regmi_guraya_jones_anderson_karcher_2019, title={Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens of four commercial genetic lines in conventional cages and enriched colony housing}, volume={98}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pey541}, DOI={10.3382/ps/pey541}, abstractNote={The prevalence of Salmonella Enteritidis in commercial egg-laying flocks is a prominent public health concern because contaminated eggs cause human illness. Deposition of this pathogen inside eggs results from bacterial colonization of reproductive tissues in infected hens. Environmental conditions can influence avian Salmonella infections, but the food safety consequences of different poultry housing systems remain uncertain. The present study assessed the invasion of internal organs by Salmonella Enteritidis in groups of experimentally infected laying hens of four commercial genetic lines (designated as white egg lines W1 and W2 and brown egg lines B1 and B2). Groups of hens from each line were housed at 555 cm2 of floor space per bird in both conventional cages and colony units enriched with access to perches and nesting areas. All hens were orally inoculated with 5.75 × 107 colony-forming units of a two-strain Salmonella Enteritidis mixture. At 6 to 7 d post-inoculation, hens were euthanized, and samples of liver, spleen, ovary, oviduct, and intestinal tract were removed for bacteriologic culturing. The frequency of Salmonella Enteritidis recovery from intestinal samples was significantly (P < 0.05) greater for the two white egg lines combined than for the two brown egg lines combined in both conventional cage (72.2% vs. 50.0%) and enriched colony housing systems (66.7% vs. 37.5%). The frequency of intestinal Salmonella Enteritidis isolation from line B1 was significantly higher from hens in conventional cages (47.2%) than in enriched colonies (22.2%), but no differences were observed for other hen lines. Line W1 yielded more positive intestinal samples than either brown egg line in conventional cages, and line B2 had fewer positive intestinal samples than all other lines in enriched colonies. There were no significant differences between hen lines or housing systems in Salmonella Enteritidis isolation from other internal organs. These results demonstrate that Salmonella Enteritidis colonization of the intestinal tract can vary between genetic lines of egg-laying hens and that some lines are subject to housing system influences on Salmonella susceptibility.}, number={4}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K and Regmi, Prafulla and Guraya, Rupa and Jones, Deana R and Anderson, Kenneth E and Karcher, Darrin M}, year={2019}, month={Apr}, pages={1785–1790} }
 @article{gast_regmi_guraya_jones_anderson_karcher_2019, title={Contamination of eggs by Salmonella Enteritidis in experimentally infected laying hens of four commercial genetic lines in conventional cages and enriched colony housing}, volume={98}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pez222}, DOI={10.3382/ps/pez222}, abstractNote={Human illness caused by the consumption of eggs contaminated with Salmonella Enteritidis is a continuing international public health concern. This pathogen is deposited inside the edible contents of eggs as a consequence of its ability to colonize reproductive tissues in infected hens. Conditions in the housing environment can influence the persistence and transmission of avian Salmonella infections, but the food safety ramifications of different poultry management systems are not entirely clear. The present study assessed the deposition of S. Enteritidis inside eggs laid by groups of experimentally infected laying hens of 4 commercial genetic lines (designated as white egg lines W1 and W2 and brown egg lines B1 and B2). Groups of hens from each line were housed at 555 cm2 of floor space per bird in both conventional cages and colony units enriched with access to perches and nesting areas. All hens were orally inoculated with 5.75 × 107 cfu of a 2-strain S. Enteritidis mixture, and the internal contents of eggs laid 5 to 24 D post-inoculation were cultured to detect the pathogen. No significant differences in egg contamination frequencies were found between the 2 housing systems for any of the hen lines. Contaminated eggs were laid between 7 and 21 D post-inoculation at an overall frequency of 2.47%, ranging from 0.25 to 4.38% for the 4 hen lines. The frequency of S. Enteritidis recovery from egg samples was significantly (P < 0.05) lower for line B2 than for any of the other lines, and the egg contamination frequency for line W1 was significantly greater than for line W2. The overall incidence of contamination among white eggs (3.38%) was significantly higher than among brown eggs (1.56%). These results demonstrate that S. Enteritidis deposition inside eggs can vary between genetic lines of infected laying hens, but housing these hens in 2 different systems did not affect the production of contaminated eggs.}, number={10}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K and Regmi, Prafulla and Guraya, Rupa and Jones, Deana R and Anderson, Kenneth E and Karcher, Darrin M}, year={2019}, month={Oct}, pages={5023–5027} }