The assessment of efficacy of porcine reproductive respiratory syndrome virus inactivated vaccine based on the viral quantity and inactivation methods

<p>Abstract</p> <p>Background</p> <p>There have been many efforts to develop efficient vaccines for the control of porcine reproductive and respiratory syndrome virus (PRRSV). Although inactivated PRRSV vaccines are preferred for their safety, they are weak at inducing humoral immune responses and controlling field PRRSV infection, especially when heterologous viruses are involved.</p> <p>Results</p> <p>In all groups, the sample to positive (S/P) ratio of IDEXX ELISA and the virus neutralization (VN) titer remained negative until challenge. While viremia did not reduce in the vaccinated groups, the IDEXX-ELISA-specific immunoglobulin G increased more rapidly and to significantly greater levels 7 days after the challenge in all the vaccinated groups compared to the non-vaccinated groups (<it>p </it>< 0.05). VN titer was significantly different in the 10⁶PFU/mL PRRSV vaccine-inoculated and binary ethylenimine (BEI)-inactivated groups 22 days after challenge (<it>p </it>< 0.05). Consequently, the inactivated vaccines tested in this study provided weak memory responses with sequential challenge without any obvious active immune responses in the vaccinated pigs.</p> <p>Conclusions</p> <p>The inactivated vaccine failed to show the humoral immunity, but it showed different immune response after the challenge compared to mock group. Although the 10⁶PFU/mL-vaccinated and BEI-inactivated groups showed significantly greater VN titers 22 days after challenge, all the groups were already negative for viremia.</p

Yoga Training Improves Metabolic Parameters in Obese Boys

Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p\u3c0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p\u3c0.01). HDL-cholesterol was decreased in both groups (p\u3c0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys

Evaluation of a competitive ELISA for antibody detection against avian influenza virus

Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity

Genetic analysis of ORF5 of recent Korean porcine reproductive and respiratory syndrome viruses (PRRSVs) in viremic sera collected from MLV-vaccinating or non-vaccinating farms

The 23 open reading frame (ORF) 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus (PRRSV) were collected from viremic sera from the (modified live vaccine) MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences, including type I Korean PRRSV, and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs, one subgroup had 87.2~88.9% similarity with the Lelystad virus, showing a close relationship with the 27~2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages, subgroups 1, 2, 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 (48%). The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion, the existence of type I PRRSV, which was genetically different from Lelystad virus (Prototype of type I PRRSV), and heterologous type II PRRSVs of viremic pigs detected even in the MLV-vaccinating farms indicated the need for new vaccine approaches for the control of PRRSV in Korea

Systemic cytokine profiles of mice vaccinated with naked DNAs encoding six open reading frame antigens of porcine circovirus type 2 (PCV2)

The objective of this study was to characterize the murine immune response to vaccination with DNAs encoding each of six porcine circovirus type 2 (PCV2) open reading frames (ORFs). After intramuscular vaccination with the naked DNAs, blood was taken on days post-infection (DPI) 7 and 35 and subjected to Bio-Plex cytokine assays. ORF3 elicited high levels of the pro-inflammatory cytokine TNF-α (P < 0.001) and decreased IL-12 levels (P < 0.001) on DPI 7, and was lethal for nine of the 15 vaccinated mice, which died on DPIs 4, 6, 9, and 10. The remaining six mice showed general prostration but then recovered. The clinical signs correlated with the systemic TNF-α and IL-12 levels. ORF1 vaccination elevated T-helper (Th)1 (IFN-γ; P < 0.001) and Th2 (IL-13; P < 0.05) cytokine levels on DPI 35, while ORF2 markedly elevated the expression of the humoral immunity- and Th-2-related cytokine IL-10 (P < 0.001) on DPI 35. These observations provide insights into the immune responses generated by each PCV2 ORF.We are grateful to Ms. Joo-Hee Park for technical assistance. This work was supported in part by the Technology Development Program for Agriculture and Forestry, Ministry of Agriculture and Forestry, Republic of Korea

Cloning and further sequence analysis of the spike gene of attenuated porcine epidemic diarrhea virus DR13

The spike (S) gene of the attenuated porcine epidemic diarrhea virus (PEDV) DR13 was cloned and sequenced to further explore the functions of wild type PEDV and attenuated PEDV. Sequencing revealed a single large ORF of 4,149 nucleotides encoding a protein of 1,382 amino acids with predicted M r of 151 kDa. The coding region of the S gene of attenuated PEDV DR13 had 20 nucleotide changes that appeared to be significant determinants of function in that they produced changes in its predicted amino acid sequence. Notably, attenuated PEDV DR13 has previously been found to exhibit reduced pathogenicity in pigs. The regions containing these 20 nucleotide changes may therefore be crucial for PEDV pathogenicity. The attenuated PEDV DR13 S protein contains 28 Asn-Xaa-Ser/Thr sequons, 21 asparagines that are predicted to be N-glycosylated and a stretch of highly hydrophobic residues at positions 1,327–1,347, which is predicted to form an α-helix and to function as a membrane anchor. One (from N to K at 378) of the changes in the deduced amino acid sequence destroyed N-linked glycosylation sites, while another change (from N to S at 114) created a new one at a different location. These alterations in N-linked glycosylation sites reflected 3 nucleotide changes, which were related to the above-mentioned nucleotide changes and are suggested to influence the pathogenicity of attenuated PEDV DR13. Attenuated PEDV DR13 has 96.5, 96.4, 96.1, 93.9, 93.5 and 96.6% DNA sequence identities with CV777, Br1/87, JS-2004-2, Spk1, Chinju99 and parent DR13, respectively. Likewise, it shares 95.7, 95.4, 95.6, 92.0, 91.6 and 95.7% identity with those genes at the deduced amino acid sequence level. Phylogenetic analysis suggested that attenuated PEDV DR13 is closely related to CV777, Br1/87, JS-2004-2 and parent DR13, rather than to Spk1 and Chinju99 and is especially close to the Chinese PEDV strain JS-2004-2.This work was supported by the Research Project on the Production of Bio-organs (No. 200503010401) Ministry of Agriculture and Forestry, Republic of Korea

Effect of Short- to Long-Term Exposure to Ambient Particulate Matter on Cognitive Function in a Cohort of Middle-Aged and Older Adults: KoGES

Exposure to ambient air pollution and its threat to human health is a global concern, especially in the elderly population. Therefore, more in-depth studies are required to understand the extent of the harmful effects of particulate matter (PM) based on duration and levels of exposure. An investigation was conducted to determine the association between short- (1&ndash;14 days), medium- (1, 3, and 6 months), and long-term (1, 2, and 3 years) exposure to air pollutants (PM2.5 and PM10) and cognitive function among Koreans (4175 participants, mean age 67.8 years, 55.2% women) aged over 50 years. Higher levels of PM2.5 exposure for short to long term and PM10 exposure for medium to long term were found to be associated with decreased cognitive function, as indicated by lower scores of the Mini-Mental State Examination adopted in Korean (K-MMSE). There were significant effect modifications by sex, age group, alcohol consumption, physical activity, and smoking status in the association between long-term PM2.5 and PM10 exposure and cognitive function. These findings, which underscore the importance of the efforts to reduce the exposure levels and durations of air pollutants, especially in the vulnerable elderly population, provide evidence for establishing more stringent policies for air pollution regulations

Serologic surveillance of swine H1 and H3 and avian H5 and H9 influenza A virus infections in swine population in Korea

Influenza A is a respiratory disease common in the swine industry. Three subtypes, H1N1, H1N2 and H3N2 influenza A viruses, are currently co-circulating in swine populations in Korea. An outbreak of the highly pathogenic avian influenza H5N1 virus occurred in domestic bird farms in Korea during the winter season of 2003. Pigs can serve as hosts for avian influenza viruses, enabling passage of the virus to other mammals and recombination of mammalian and avian influenza viruses, which are more readily transmissible to humans. This study reports the current seroprevalence of swine H1 and H3 influenza in swine populations in Korea by hemagglutination inhibition (HI) assay. We also investigated whether avian H5 and H9 influenza transmission occurred in pigs from Korea using both the HI and neutralization (NT) tests. 51.2% (380/742) of serum samples tested were positive against the swine H1 virus and 43.7% (324/742) were positive against the swine H3 virus by HI assay. The incidence of seropositivity against both the swine H1 virus and the swine H3 virus was 25.3% (188/742). On the other hand, none of the samples tested showed seropositivity against either the avian H5 virus or the avian H9 virus by the HI and NT tests. Therefore, we report the high current seroprevalence and co-infectivity of swine H1 and H3 influenza viruses in swine populations and the lack of seroepidemiological evidence of avian H5 and H9 influenza transmission to Korean pigs.We thank Chul-Seung Lee (Department of Veterinary Virology, College of Veterinary Medicine, Seoul National University) for assisting us with sample preparation