• Journal of Animal Science and Technology
• /
• v.65 no.2
• /
• pp.441-458
• /
• 2023

The poultry industry, which produces excellent sources of protein, suffers enormous economic damage from diseases. To solve this problem, research is being conducted on the early detection of infection according to the behavioral characteristics of poultry. The purpose of this study was to evaluate the potential of a non-movement behavior observation method to detect sick chickens. Forty 1-day-old Ross 308 males were used in the experiments, and an isolator equipped with an Internet Protocol (IP) camera was fabricated for observation. The chickens were inoculated with Salmonella enterica serovar Gallinarum A18-GCVP-014, the causative agent of fowl typhoid (FT), at 14 days of age, which is a vulnerable period for FT infection. The chickens were continuously observed with an IP camera for 2 weeks after inoculation, chickens that did not move for more than 30 minutes were detected and marked according to the algorithm. FT infection was confirmed based on clinical symptoms, analysis of cardiac, spleen and liver lesion scores, pathogen re-isolation, and serological analysis. As a result, clinical symptoms were first observed four days after inoculation, and dead chickens were observed on day six. Eleven days after inoculation, the number of clinical symptoms gradually decreased, indicating a state of recovery. For lesion scores, dead chickens scored 3.57 and live chickens scored 2.38. Pathogens were re-isolated in 37 out of 40 chickens, and hemagglutination test was positive in seven out of 26 chickens. The IP camera applied with the algorithm detected about 83% of the chickens that died in advance through non-movement behavior observation. Therefore, observation of non-movement behavior is one of the ways to detect infected chickens in advance, and it appears to have potential for the development of remote broiler management system.

• Food Science of Animal Resources
• /
• v.42 no.2
• /
• pp.225-239
• /
• 2022

As commensal colonizers in livestock, there has been little attention on staphylococci, especially non-aureus staphylococci (NAS), contaminating meat production chain. To assess prevalence of staphylococci in retail pork and slaughterhouse carcass samples in Korea, we collected 578 samples from Korean slaughterhouses (n=311) and retail markets (n=267) for isolation of staphylococci and determined antimicrobial resistance phenotypes in all the isolates. The presence of and prevalence of fusB-family genes (fusB, fusC, fusD, and fusF) and mutations in fusA genes were examined in fusidic acid resistant isolates. A total of 47 staphylococcal isolates of 4 different species (Staphylococcus aureus, n=4; S. hyicus, n=1; S. epidermidis, n=10; Mammaliicoccus sciuri, n=32) were isolated. Fusidic acid resistance were confirmed in 9/10 S. epidermidis and all of the 32 M. sciuri (previously S. sciuri) isolates. Acquired fusidic acid resistance genes were detected in all the resistant strains; fusB and fusC in S. epidermidis and fusB/C in M. sciuri. Multi-locus sequence type analysis revealed that ST63 (n=10, 31%) and ST30 (n=8, 25%) genotypes were most prevalent among fusidic acid resistant M. sciuri isolates. In conclusion, the high prevalence of fusB-family genes in S. epidermidis and M. sciuri strains isolated from pork indicated that NAS might act as a reservoir for fusidic acid resistance gene transmissions in pork production chains.

• Food Science of Animal Resources
• /
• v.43 no.4
• /
• pp.563-579
• /
• 2023

Myogenesis and adipogenesis are the important processes determining the muscle growth and fat accumulation livestock, which ultimately affecting their meat quality. Hanwoo is a popular breed and its meat has been exported to other countries. The objective of this study was to compare the myogenesis and adipogenesis properties in satellite cells, and meat quality between Hanwoo and Vietnamese yellow cattle (VYC). Same 28-months old Hanwoo (body weight: 728±45 kg) and VYC (body weight: 285±36 kg) steers (n=10 per breed) were used. Immediately after slaughter, tissue samples were collected from longissimus lumborum (LL) muscles for satellite cells isolation and assays. After 24 h post-mortem, LL muscles from left carcass sides were collected for meat quality analysis. Under the same in vitro culture condition, the proliferation rate was higher in Hanwoo compared to VYC (p<0.05). Fusion index was almost 3 times greater in Hanwoo (42.17%), compared with VYC (14.93%; p<0.05). The expressions of myogenesis (myogenic factor 5, myogenic differentiation 1, myogenin, and myogenic factor 6)- and adipogenesis (peroxisome proliferator-activated receptor gamma)-regulating genes, and triglyceride content were higher in Hanwoo, compared with VYC (p<0.05). Hanwoo beef had a higher intramuscular fat and total monounsaturated fatty acids contents than VYC beef (p<0.05). Whilst, VYC meat had a higher CIE a* and total polyunsaturated fatty acids content (p<0.05). Overall, there was a significant difference in the in vitro culture characteristics and genes expression of satellite cells, and meat quality between the Hanwoo and VYC.

• Food Science of Animal Resources
• /
• v.43 no.4
• /
• pp.685-702
• /
• 2023

Lactic acid bacteria (LAB) are commonly used as probiotics; however, not all LAB strains have the same beneficial effects. To successfully use LAB as probiotics in canines, LAB species should originate from the canine intestinal tract as they display host specificity. The objective of this study was to investigate the phenotypic and genomic traits of potential probiotic LAB isolated from canine fecal samples. Twenty LAB samples were evaluated for their potential probiotic characteristics including resistance to low pH, bile salts, hydrophobicity, auto-aggregation, co-aggregation, adhesion to epithelia or mucosa, and production of inhibitory compounds. Additionally, we evaluated their safety and other beneficial effects on canine health, such as DPPH free radical scavenging, and β-galactosidase. Four strains demonstrated potential probiotic characteristics and were selected: Enterococcus hirae Pom4, Limosilactobacillus fermentum Pom5, Pediococcus pentosaceus Chi8, and Ligilactobacillus animalis FB2. Safety evaluations showed that all strains lacked hemolytic activity, could not produce biogenic amines, and did not carry any pathogenic genes. In addition, L. fermentum Pom5 and P. pentosaceus Chi8 displayed susceptibility to all antibiotics and concordant with the absence of antibiotic resistance genes. Based on their phenotypic and genomic characteristics, L. fermentum Pom5 and P. pentosaceus Chi8 were identified as potential probiotic candidates for canines.

• Mycobiology
• /
• v.51 no.4
• /
• pp.246-255
• /
• 2023

Genus Penicillium comprising the most important and extensively studied fungi has been well-known as a rich source of secondary metabolites. Our study aimed to analyze and investigate biological activities, including in vitro anti-cancer, anti-inflammatory and anti-diabetic properties, of metabolites from a marine-derived fungus belonging to P. levitum. The chemical compounds in the culture broth of P. levitum strain N33.2 were extracted with ethyl acetate. Followingly, chemical analysis of the extract leaded to the isolation of three ergostane-type steroid components, namely cerevisterol (1), ergosterol peroxide (2), and (3β,5α,22E)-ergosta-6,8(14),22-triene-3,5-diol (3). Among these, (3) was the most potent cytotoxic against human cancer cell lines Hep-G2, A549 and MCF-7 with IC₅₀ values of 2.89, 18.51, and 16.47 ㎍/mL, respectively, while the compound (1) showed no significant effect against tested cancer cells. Anti-inflammatory properties of purified compounds were evaluated based on NO-production in LPS-induced murine RAW264.7 macrophages. As a result, tested compounds performed diverse inhibitory effects on NO production by the macrophages, with the most significant inhibition rate of 81.37±1.35% at 25 ㎍/mL by the compound (2). Interestingly, compounds (2) and (3) exhibited inhibitory activities against pancreatic lipase and α-glucosidase enzymes in vitro assays. Our study brought out new data concerning the chemical properties and biological activities of isolated steroids from a P. levitum fungus.

• Pediatric Infection and Vaccine
• /
• v.31 no.1
• /
• pp.147-152
• /
• 2024

There have been several case reports of neurological manifestations in pediatrics as severe acute respiratory syndrome coronavirus-2 infection in children is being increased. We report a case of a 4-year-old boy who presented febrile seizure during follow-up in a negative pressure isolation room after confirmed coronavirus disease 2019, which has not yet been reported in Korea. He has no symptoms other than fever. The seizure was controlled after one dose of intravenous lorazepam, and there was no respiratory support during the hospitalization. He was discharged 12 days later without neurological sequelae.

• Journal of Chest Surgery
• /
• v.57 no.2
• /
• pp.136-144
• /
• 2024

Background: Early non-small cell lung cancer (NSCLC) that abuts adjacent structures requires careful evaluation due to its potential impact on postoperative outcomes and prognosis. We examined stage I NSCLC with invasion into adjacent structures, focusing on the prognostic implications after curative surgical resection. Methods: We retrospectively analyzed the records of 796 patients who underwent curative surgical resection for pathologic stage IA/IB NSCLC (i.e., visceral pleural invasion only) at a single center from 2008 to 2017. Patients were classified based on tumor abutment and then reclassified by the presence of visceral pleural invasion. Clinical characteristics, pathological features, and survival rates were compared. Results: The study included 181 patients with abutting NSCLC (22.7% of all participants) and 615 with non-abutting tumors (77.3%). Those with tumor abutment exhibited higher rates of non-adenocarcinoma (26.5% vs. 9.9%, p<0.01) and visceral/lymphatic/vascular invasion (30.4%/33.1%/12.7% vs. 8.5%/22.4%/5.7%, respectively; p<0.01) compared to those without abutment. Multivariable analysis identified lymphatic invasion and male sex as risk factors for overall survival (OS) and disease-free survival (DFS) in stage I NSCLC measuring 3 cm or smaller. Age, smoking history, vascular invasion, and recurrence emerged as risk factors for OS, whereas the presence of non-pure ground-glass opacity was a risk factor for DFS. Conclusion: NSCLC lesions 3 cm or smaller that abut adjacent structures present higher rates of various risk factors than non-abutting lesions, necessitating evaluation of tumor invasion into adjacent structures and lymph node metastasis. In isolation, however, the presence of tumor abutment without visceral pleural invasion does not constitute a risk factor.

• IMMUNE NETWORK
• /
• v.22 no.6
• /
• pp.49.1-49.15
• /
• 2022

Exosomes derived from mesenchymal stem cells (MSCs) could protect against myocardial infarction (MI). TLR4 is reported to play an important role in MI, while microRNA-182-5p (miR-182-5p) negatively regulates TLR4 expression. Therefore, we hypothesize that MSCs-derived exosomes overexpressing miR-182-5p may have beneficial effects on MI. We generated bone marrow mesenchymal stem cells (BM-MSCs) and overexpressed miR-182-5p in these cells for exosome isolation. H₂O₂-stimulated neonatal mouse ventricle myocytes (NMVMs) and MI mouse model were employed, which were subjected to exosome treatment. The expression of inflammatory factors, heart function, and TLR4 signaling pathway activation were monitored. It was found that miR-182-5p decreased TLR4 expression in BM-MSCs and NMVMs. Administration of exosomes overexpressing miR-182-5p to H₂O₂-stimulated NMVMs enhanced cell viability and suppressed the expression of inflammatory cytokines. In addition, they promoted heart function, suppressed inflammatory responses, and de-activated TLR4/NF-κB signaling pathway in MI mice. In conclusion, miR-182-5p transferred by the exosomes derived from BM-MSCs protected against MI-induced impairments by targeting TLR4.

• IMMUNE NETWORK
• /
• v.21 no.6
• /
• pp.39.1-39.18
• /
• 2021

The high virulent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that emerged in China at the end of 2019 has generated novel coronavirus disease, coronavirus disease 2019 (COVID-19), causing a pandemic worldwide. Every country has made great efforts to struggle against SARS-CoV-2 infection, including massive vaccination, immunological patients' surveillance, and the utilization of convalescence plasma for COVID-19 therapy. These efforts are associated with the attempts to increase the titers of SARS-CoV-2 neutralizing Abs (nAbs) generated either after infection or vaccination that represent the body's immune status. As there is no standard therapy for COVID-19 yet, virus eradication will mainly depend on these nAbs contents in the body. Therefore, serological nAbs neutralization assays become a requirement for researchers and clinicians to measure nAbs titers. Different platforms have been developed to evaluate nAbs titers utilizing various epitopes sources, including neutralization assays based on the live virus, pseudovirus, and neutralization assays utilizing recombinant SARS-CoV-2 S glycoprotein receptor binding site, receptor-binding domain. As a standard neutralization assay, the plaque reduction neutralization test (PRNT) requires isolation and propagation of live pathogenic SARS-CoV-2 virus conducted in a BSL-3 containment. Hence, other surrogate neutralization assays relevant to the PRNT play important alternatives that offer better safety besides facilitating high throughput analyses. This review discusses the current neutralization assay platforms used to evaluate nAbs, their techniques, advantages, and limitations.

• Journal of agricultural medicine and community health
• /
• v.30 no.2
• /
• pp.137-149
• /
• 2005

Objectives and Methods: This study was performed to investigate the etiologic bacterial, viral and protozoal organisms for the diarrhea from hospitals in Chungnam area from January to December in 2004. Total of 787 fecal samples were collected and examined. Results and Conclusions: In test for enteropathogenic bacteria, total of 79 cases out of 787 samples from hospitals showed positive isolation. Among 79 positive samples, 27 cases were confirmed as Salmonella spp.. 20 cases as pathogenic E. coli, 18 cases as Clostridium perfringens, 6 cases as Staphylococcus aureus, 4 cases as Shigella spp. and 4 cases as Vibrio parahaemolyticus. In test for enteropathogenic virus, 190 cases out of 787 samples from hospitals showed positive reaction. Among 190 samples, 115 cases were confirmed as rotavirus, 55 cases as norovirus, 5 case as astrovirus, 4 case as rotavirus & norovirus, 3 cases as adenovirus, 2 case as rotavirus & astrovirus. In test for enteropathogenic protozoa, 6 cases out of 787 samples from hospitals showed positive result. Among 6 samples, 5 cases were confirmed as Entamoeba histolytica and 1 cases as Giardia lamblia. When we classified the positive results by the age of the patients, the highest isolation rate was noted in a group of age under 10 and over 60 for bacterial, viral and protozoal pathogens. Especially, patient below age of 5 showed high positive rate. When we classified the positive results by the time, pageathogenic bacteria were isolated throughout the year, and the highest frequency was noted in August. On the other hand, pathogenic viruses were detected more frequently during the colder season from December to April. Antimicrobial susceptibility test for the isolated bacteria resulted as follows; Salmonella strains showed high drug resistance rates against ampicillin, chloramphenicol, tetracycline, nalidixic acid, ticarcillin. Shigella strains showed high drug resistance rates against ampicillin, trimethoprim/sulfamethoxazole, chloramphenicol, tetracycline, ampicillin/sulbactam, ticarcillin. Pathogenic E. coli strains showed high drug resistance rates against ampicillin, cephalothin, gentamicin, tetracycline, nalidixic acid, ampicillin/sulbactam, ticarcillin.