PCR-based specific and sensitive detection of Pectobacterium carotovorum ssp. carotovorum by primers generated from a URP-PCR fingerprinting-derived polymorphic band

A 24-mer primer pair was generated by sequencing a URP-PCR fingerprinting-derived polymorphic band that is uniquely shared in Pectobacterium carotovorum ssp . carotovorum strains (Pcc). The primer set (EXPCCF/EXPCCR) amplified a single band of expected size (0·55 kb) from genomic DNA obtained from 29 Pcc strains and three Pectobacterium carotovorum ssp. wasabiae (Pcw) strains, but not from other P. carotovorum subspecies atrosepticum , betavasculorum or odoriferum , or from other Erwinia spp. or bacterial genera. The Rsa I digestion profile of the amplified bands divided Pcc strains into five groups with a unique profile from Pcw strains. First-round PCR detected between 5 × 10² and 1 × 10³ colony forming units (CFU) mL⁻¹ and detection sensitivity was increased to as few as 2–4 CFU mL⁻¹ after second-round (nested) PCR. This PCR protocol was used directly to detect Pcc strains in infected plant tissues.     

Protective effects of bio-active ceramic water on alcohol-induced hepatic injury in pigs

Among many detrimental injuries, alcohol is implicated in hepatitis, fatty liver, hepatic fibrosis, and cirrhosis. The purpose of this study was to evaluate the protective effect of bio-active ceramic water on alcohol-induced hepatic injury in pigs. Twelve male Landrace pigs were divided into 3 groups. Groups 1, 2, and 3 were fed with bio-active ceramic water + normal liquid diet, bio-active ceramic water + liquid diet containing 15% ethanol, and tap water + liquid diet containing 15% ethanol for 12 weeks, respectively. For serological, histopathological, and immunohistochemical analysis, all pigs were sacrificed at week 12. In group 3, serum ALT and AST levels increased, and mild fatty change and moderate necrosis were detected in the liver. Collagen fibers, myofibroblasts, and CYP2E1 were also increased or activated in group 3. In group 2, there were mild hepatic injuries compared to group 3. However, injuries and activations were not observed in the liver in group 1. We suggest that the bio-active ceramic water used in the present study had protective capability against ethanol-induced hepatic injury and that having no toxic effect on the pig liver. The bio-active ceramic water might be useful as a therapeutic drinking water in patients suffering from alcoholic liver diseases.     

Effects of dizocilpine pretreatment on parvalbumin immunoreactivity and Fos expression after cerebral ischemia in the hippocampus of the Mongolian gerbil

The mechanisms of ischemic neuronal death have been focused on glutamate receptor activation and subsequent elevation of intracellular Ca2+ concentration. The purpose of this study was to evaluate the effects of dizocilpine, an NMDA receptor antagonist, pretreatment on Fos expression and parvalbumin (PV, calcium binding protein) immunoreactivity in the hippocampus of the mongolian gerbil after global ischemic insults. The number of PV-immunoreactive (PV-ir) neurons in CA1 were significantly decreased from 1 day after cerebral ischemia, while dizocilpine pretreatment completely suppressed the loss of PV-ir neurons in CA1. Dizocilpine pretreatment also protected the structural loss of microtubule-associated protein 2 immunoreactivity in CA1 after ischemic insults. In addition, dizocilpine pretreatment increased Fos expression in both hippocampal CA3 and CA4 after 3 hr ischemic reperfusion as compared to that of the saline pretreated group. Subsequently, the Fos-defined cellular activity of PV-ir neurons was slightly increased by dizocilpine pretreatment in the hippocampal area. This study demonstrated that NMDA receptor mediated calcium influx was associated with the loss of PV-ir neurons in CA1 hippocampal region, and that dizocilpine pretreatment increased Fos expression and the neuronal activity of PV-ir neurons in the non-vulnerable region of hippocampus after cerebral ischemia. Based on this data, we conclude that the protective effect of dizocilpine may be induced by the regulation of calcium overload, or by the upregulation of a neuroregenerative initiator such as Fos protein.     

Clinical features and management of snake bites in 70 dogs in Korea

BackgroundSnakebites remain a devastating and life-threatening environmental hazard. While the management of snakebites has been well described in humans, few clinical data and guidelines exist for dogs, especially in Korea.ObjectivesThis retrospective study evaluated the clinical features of 70 dogs with snakebite wounds in Korea.MethodsThe medical records of 72 dogs that presented to three animal hospitals from June 2008 to July 2021 were reviewed; among these, 70 dogs that met the inclusion criteria were enrolled. Their signalment, history, clinical signs, physical examination, blood analysis, treatment, and prognosis were also evaluated.ResultsOf 70 dog owners, 35 (50%) witnessed the bite, with a mean time between bite and hospital presentation of 9.7 ± 4.1 h in 58 dogs. Blood smears were evaluated in 45 dogs, of which 28 (62%) showed echinocytosis. Anemia and acute kidney injury were found in 21 (29%) and 2 dogs (3%), respectively. A total of 37 dogs (53%) were hospitalized, 5 (7%) of which died.ConclusionsThe most significant finding was the high prevalence of echinocytosis. The data from this retrospective study could inform the management of dogs bitten by snakes in Korea.     

Accelerated Growth, Gigantism and Likely Sterility in Autotransgenic Triploid Mud Loach Misgurnus mizolepis

Triploidy was induced in two selected lines of autotransgenic mud Ioach Misgurnus mizolepis containing no heterospecific genetic material. Cytological evaluations, including cellular DNA content, chromosome count, and erythrocyte measurement, proved the successful induction of triploidy. Patterns of Southern blot hybridization and tissue distribution of GH mRNA in autotransgenic triploids were similar to those of diploid autotransgenics. The autotransgenic triploids also displayed growth acceleration 22–25 times that of nontransgenic diploids, although the acceleration was relatively modest when compared to their diploid transgenic counterparts (more than a 30-fold increase). Significantly improved feed conversion was observed in both autotransgenic diploids and triploids, ranging from 1.8 to 2.0 times that in nontransgenics. Autotransgenic triploids were sterile at gonadal level, evidenced by significantly retarded and abnormal gametogenesis. With the persistence of accelerated growth and enhanced feed conversion efficiency, the autotransgenic triploid mud loach may offer economic benefits to aquaculture. Total absence of heterospecific genetic material and sterility may also allay public concern regarding food safety and environmental risk of crossbreeding between transgenics and conspecific populations.     

Hematological adverse effects and pharmacokinetics of ribavirin in pigs following intramuscular administration

Ribavirin (RBV) is a synthetic guanosine analog that is used as a drug against various viral diseases in humans. The in vitro antiviral effects of ribavirin against porcine viruses were demonstrated in several studies. The purposes of this study were to evaluate the adverse effects and pharmacokinetics of ribavirin following its intramuscular (IM) injection in pigs. Ribavirin was formulated as a double‐oil emulsion (RBV‐DOE) and gel (RBV‐Gel), which were injected into the pigs as single‐dose IM injections. After injection of RBV, all of the pigs were monitored. The collected serum and whole blood samples were analyzed by liquid chromatography–tandem mass spectrometry and complete blood count analysis, respectively. All of the ribavirin‐treated pigs showed significant decreases in body weight compared to the control groups. Severe clinical signs including dyspnea, anorexia, weakness, and depression were present in ribavirin‐treated pigs until 5 days postinjection (dpi). The ribavirin‐treated groups showed significant decrease in the number of red blood cells and hemoglobin concentration until 8 dpi. The mean half‐life of the RBV‐DOE and RBV‐Gel was 27.949 ± 2.783 h and 37.374 ± 3.502 h, respectively. The mean peak serum concentration (C_max) and area under the serum concentration–time curve from time zero to infinity (AUC_inf) of RBV‐DOE were 8340.000 ± 2562.577 ng/mL and 16 0095.430 ± 61 253.400 h·ng/mL, respectively. The C_max and AUC_inf of RBV‐Gel were 15 300.000 ± 3764.306 ng/mL and 207526.260 ± 63656.390 h·ng/mL, respectively. The results of this study provided the index of side effect and pharmacokinetics of ribavirin in pigs, which should be considered before clinical application.     

Transient ischaemia affects plasma membrane glutamate transporter, not vesicular glutamate transporter, expressions in the gerbil hippocampus

In the present study, we investigated expressions of vesicular glutamate transporter (VGLUT) and of the plasma membrane glutamate transporters [glutamate transporter 1 (GLT-1), glutamate/aspartate transporter (GLAST) and excitatory amino acid carrier 1 (EAAC-1)] in the gerbil hippocampus following transient ischaemia. The expressional levels and distribution patterns of VGLUT immunoreactivities were unaltered until 3 days after ischaemic-insults. However, VGLUT-2 immunoreactivity in the CA1 region was reduced at 4 days after ischaemia due to delayed neuronal death. In addition, both GLT-1 and GLAST immunoreactivities in the CA1 region were enhanced at 30 min - 12 h after ischaemia-reperfusion and their expression began to reduce at 24 h after ischaemia-reperfusion. In contrast, EAAC-1 immunoreactivity was transiently reduced in the CA1 region at 30 min after ischaemia, re-enhanced at 3-12 h after ischaemia, and re-reduced at 24 h after ischaemia. These findings suggest that malfunctions of plasma membrane glutamate transporters, not of VGLUT, may play an important role in the elevation of extracellular glutamate concentration following ischaemic insults.     

Molecular characterization of recent Korean porcine reproductive and respiratory syndrome (PRRS) viruses and comparison to other Asian PRRS viruses

Twenty-eight PRRS viruses (PRRSVs) isolated from various pig farms in Korea between 2002 and 2003 were sequenced for open-reading frame (ORF) 5 and/or full-length genome and compared with numerous PRRSVs reported from North America, Europe and Asia. All Korean isolates examined were genetically of the North American genotype. The ORF5 sequence of one isolate was identical to Ingelvac PRRS MLV vaccine virus. ORF5 nucleotide sequence divergence of the remaining 27 Korean PRRSVs from VR-2332, the prototype of the North American PRRSV and parental strain of the MLV vaccine virus, ranged from 1.3% to 12.9%, which corresponded to 2.0% to 14.9% divergence at the amino acid level, raising a concern on the efficacy of the MLV vaccine. Phylogenetic analyses of ORF5 and/or full-length sequences revealed that the Korean PRRSVs formed a clade distinct from PRRSVs reported from other Asian countries (China, Taiwan, Japan, and Thailand). Our study demonstrated that PRRSVs of the North American genotype were introduced to the Korean swine population some time ago and have evolved independently from PRRSV in other Asian countries, suggesting that geographic separation might influence the molecular evolution of PRRSV. This should be taken into consideration when a national PRRS prevention and control policy for international trade is established.     

Antimicrobial resistance in Salmonella enterica serovars Enteritidis and Typhimurium isolated from animals in Korea: comparison of phenotypic and genotypic resistance characterization

Fourteen and 22 each of Salmonella Enteritidis and Salmonella Typhimurium (S. Typhimurium) were isolated from animals from 1983 to 1999 in Korea and tested for their antibiotic resistance patterns, phage types and resistance gene patterns. S. Typhimurium isolates were highly resistant to streptomycin, sulfisoxazole and tetracycline, 95, 95 and 86%, respectively. The incidence of multiple antibiotic resistance (resistant to more than two drugs tested) of S. Typhimurium isolates was extremely high (100%) comparing to S. Enteritidis isolates (21%). Two of the five ACSSuT (ampicillin, chloramphenicol, streptomycin, sulfisoxazole and tetracycline) resistant type S. Typhimurium isolates were phage type definitive type 104 (DT104).For the detection of resistance related genes in S. Enteritidis and S. Typhimurium isolates, particularly ACSSuT type S. Typhimurium, antibiotic resistance genes, cmlA/tetR, bla(PSE-1) and bla(TEM), and genus Salmonella specific gene, sipB/C, were amplified using four pairs of primers in a hot-start multiplex polymerase chain reaction (PCR). Two Korean isolates of S. Typhimurium DT104 showed bla(TEM) amplicons instead of bla(PSE-1) for the ampicillin resistance and they were susceptible to florfenicol. The multiplex PCR used in this study was useful in characterization of multiple drug resistant Salmonella isolates, especially ACSSuT type S. Typhimurium, and identification of beta-lactamase gene distribution among Salmonella isolates.     

Molecular epidemiological investigation of Newcastle disease virus from domestic ducks in Korea

To expand the epidemiological understanding of Newcastle disease virus (NDV) found in domestic ducks in Korea, 14 NDV isolates from apparently healthy domestic ducks were biologically and genetically characterized. Thirteen and 1 isolates of NDV were categorized into lentogenic and velogenic viruses, respectively, based on in vivo pathogenicity tests. Twelve lentogenic viruses showed HA activity to horse RBCs, while 1 lentogenic virus and the velogenic virus were negative. Lentogenic viruses (n=13) had sequence motifs of (112)ERQERL(117) (n=1) or (112)GRQGRL(117) (n=12) at the F0 cleavage site, while the velogenic virus (n=1) had a sequence motif of (112)RRQKRF(117) at the same site. Phylogenetic analysis revealed that at least three distinct genotypes may exist in domestic ducks in Korea; one class I genotype (genotype 2), and two class II (genotypes I and VII) genotypes. The class I virus was most closely related to strains of genotype 2 which were isolated in birds from the USA, Germany and Denmark. Twelve lentogenic class II viruses were grouped together in genotype I, and were then divided into at least three clusters, namely Aomori-like, Ulster2C-like, and V4-like. The velogenic class II virus was assigned to genotype VII which represents viruses responsible for recent epidemics in many Asian countries including Korea. The epidemiological importance of domestic duck isolates of NDV in Korea is discussed.