The Effects of Local Treatment of PTH(1-34) and Whitlockite and Hydroxyapatite Graft to the Calvarial Defect in a Rat Osteoporosis Model.

With the aging population, there is a rising incidence of senile diseases, notably osteoporosis, marked by fractures, prolonged recovery, and elevated mortality rates, underscoring the urgency for effective treatments. In this study, we applied the method of absorbing parathyroid hormone (PTH), a treatment for osteoporosis, into graft materials. Two types of graft materials with different properties, whitlockite (WH) and hydroxyapatite (HAP), were used. After forming calvarial defects in osteoporotic rats, WH and HAP grafts were implanted, with PTH applied directly to the graft sites. Micro-CT analysis was employed to assess bone regeneration, while tissue sections were stained to elucidate the regeneration process and bone cell dynamics. The results showed that bone regeneration was higher in the grafts that were actively degraded by osteoclasts in the early stage of regeneration. When PTH was applied, osteoclast activity increased, leading to enhanced bone regeneration. Furthermore, the activation of osteoclasts resulted in the penetration and formation of new bone within the degraded graft, which exhibited higher osseointegration. Therefore, for osteoporotic bone defects, bone grafts that can be easily degraded by osteoclasts are more suitable. Additionally, treatment with PTH can activate osteoclasts around the bone graft in the early stages of regeneration, inducing higher bone regeneration and improving osseointegration.

A novel chimeric vaccine candidate for porcine reproductive and respiratory syndrome virus (PRRSV) I and II elicits neutralizing antibodies against both types.

Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important virus within the swine industry. The virus causes respiratory disease and reproductive failure. Two species of PRRSV-I and II are co-dominant, yet no effective vaccination strategy has been developed to protect against these two types. With an aim to develop a chimeric vaccine strain to protect against both types, in this study, a chimeric porcine reproductive and respiratory syndrome virus (PRRSV) type I and II was rescued using reverse genetics for the first time. Four chimeric infectious clones were designed based on the genomic arrangement of the structural proteins. However, only the clone carrying the transcriptional regulatory sequence (TRS) and ORF6 of a PRRSV-I and ORF6 of a PRRSV-II generated a viable recombinant virus, suggesting that concurrent expression of ORF6 from both parental viruses is essential for the recovery of type I and II chimeric PRRSV. The chimeric virus showed significantly lower replication ability than its parental strains in vitro, which was improved by serial passaging. In vivo, groups of pigs were inoculated with either the chimeric virus, one of the parental strains, or PBS. The chimeric virus replicated in pig tissue and was detected in serum 7 days post-inoculation. Serum neutralization tests indicated that pigs inoculated with the chimeric virus elicited neutralizing antibodies that inhibited infection with strains of both species and with greater coverage than the parental viruses. In conclusion, the application of this technique to construct a chimeric PRRSV holds promise for the development of a highly effective modified live vaccine candidate. This is particularly significant since there are currently no approved commercial divalent vaccines available to combat PRRSV-I and II co-infections.

Application of codon pair deoptimization for ORF7-induced attenuation of type I porcine reproductive and respiratory syndrome virus without reduced immune responses.

Codon pair deoptimization (CPD) attenuated type I porcine reproductive and respiratory syndrome virus (PRRSV). Infectious clones covering the full genome of a Korean type I PRRSV (E38) were synthesized, and CPD induced nine synonymous mutants of NSP1 (n = 1) and ORF7 (n = 8). In a trial to rescue live viruses from infectious clones, only four clones with mutations at nt 177 downstream of ORF7 were rescued, which showed a substantial decrease in cellular replication ability. The rescue-failed clones had two common mutation sites with a high minimum free energy and significantly modified RNA secondary structure relative to the original virus. In infected pigs, CPD viruses demonstrated significantly lower replication ability and pathogenicity than the original virus. However, immune response level induced by the attenuated viruses and the original virus was similar. This is the first study to demonstrate that type I PRRSV virulence can be attenuated through CPD application to ORF7.

Impact of COVID-19 on physical activity: A rapid review.

Background: Physical activity is a commonly prescribed medicine for people with conditions such as obesity and diabetes who are also at increased risk of being hospitalized or severely ill from COVID-19. However, many people are reporting challenges in engaging in a healthy dose of physical activity amid the pandemic. Objective: This rapid review synthesizes the current empirical evidence about the impacts of COVID-19 on people's outdoor physical activity and sedentary behavior while highlighting the role of community environments in promoting or hindering physical activity during the pandemic. Methods: Literature searches were conducted using keywords related to COVID-19: physical activity, mobility, and lifestyle behaviors. Eligibility criteria were peer-reviewed empirical and quantitative studies published in English, addressing COVID-19 and using physical activity and/or sedentary behavior as the study outcomes. Results: Out of 61 eligible studies, the majority (78.3%) were conducted in Asian and European countries, with only four (6.7%) being US studies. The results showed that COVID-19 was linked with significant decreases in mobility, walking, and physical activity, and increases in sedentary activity. A few studies also reported contradicting results including increased uses of parks/trails and increased recreational activity among certain groups of population. Conclusions: Evidence suggests an overall negative impact of COVID-19 on physical activity, with differential effects across different sub-populations. Significant knowledge gaps are also found in the roles of social and physical attributes that can promote physical activity during pandemics with reduced safety risks.

Synergistic Effect of Whitlockite Scaffolds Combined with Alendronate to Promote Bone Regeneration.

BACKGROUND: Due to the increasing aging of society, the number of patients suffering from senile diseases is increasing. Patients suffering from osteoporosis, which is a representative senile disease, take a long time to recover from fractures, and the resulting mortality rate is very high. Alendronate (Ald), which is widely used as a treatment for osteoporosis, alleviates osteoporosis by inhibiting osteoclasts. In addition, whitlockite (WH) promotes the osteogenic differentiation of bone cells and improves bone regeneration. Therefore, we intended to bring about a synergistic effect by using these substances together. METHODS: In this study, a scaffold composed of gelatin/heparin was fabricated and applied to effectively use WH and Ald together. A scaffold was constructed using gelatin and heparin was used to effectively utilize the cations released from WH. In addition, it formed a porous structure for effective bone regeneration. In vitro and in vivo osteoclast inhibition, osteogenic differentiation, and bone regeneration were studied using the prepared scaffolds. RESULTS: The inhibition of osteoclast was much higher when WH and Ald were applied in combination rather than individually. The highest level of osteogenic differentiation was observed when both substances were applied simultaneously. In addition, when applied to bone regeneration through the mouse calvarial defect model, combined treatment showed excellent bone regeneration. CONCLUSION: Therefore, this study showed the synergistic effect of WH and Ald, and it is suggested that better bone regeneration is possible by applying this treatment to bones with fractures that are difficult to regenerate.

Sequential growth factor releasing double cryogel system for enhanced bone regeneration.

Bone regeneration is a complicated physiological process regulated by several growth factors. In particular, vascular endothelial growth factor (VEGF) and bone morphogenetic protein-4 (BMP-4) are regarded as key factors that induce bone regeneration by angiogenesis and osteogenesis. In this study, we developed a double cryogel system (DC) composed of gelatin/chitosan cryogel (GC) surrounded by gelatin/heparin cryogel (GH) for dual drug delivery with different release kinetics. VEGF was loaded in GH (outer layer of DC) for the initial release of VEGF to induce angiogenesis and provide blood supply in the defect area, while BMP-4 was loaded in GC (inner layer of DC) that leads to sustained release for continuous osteogenic induction. After analyzing characteristics of the double cryogel system such as porosity, degradation rate, swelling ratio, and mechanical properties, we evaluated release kinetics of VEGF (initial release) and BMP-4 (sustained-release) by ELISA. Then, the timely release of VEGF and BMP from DC synergistically induced in vitro osteogenic differentiation as confirmed by alkaline phosphatase staining, Alizarin Red S staining, and real-time PCR analysis. Finally, a critical-sized cranial defect model confirmed the enhanced bone regeneration as a result of dual release growth factor mechanisms.

Field porcine reproductive and respiratory syndrome viruses (PRRSV) attenuated by codon pair deoptimization (CPD) in NSP1 protected pigs from heterologous challenge.

Two type 2 field porcine reproductive and respiratory syndrome viruses (PRRSV) isolated from PRRS-affected swine farms were attenuated by de-optimization of codon pair bias in NSP1. In 3-week-old pigs infection, the attenuated viruses showed significantly lower replication ability than the original viruses without distinct clinical sign and pathological lesions, which were observed in pig infected with the original viruses. Regarding induction of PRRSV specific immunity, the level of the neutralizing antibodies as well as secretion of IFN-γ-SCs in PBMCs was not different between the attenuated viruses and the original viruses. More importantly, pigs infected with the attenuated viruses exhibited significant reduction in respiratory scores, viremia, macroscopic and microscopic lung lesion scores, and PRRSV-antigen with interstitial pneumonia against a heterologous challenge with a type 2 virulent strain. Conclusively, the viruses attenuated by CPD in this study demonstrated potential usefulness as vaccine strains to provide protective immunity against diverse virulent PRRSVs.

A comparison of two commercially available porcine reproductive and respiratory syndrome virus (PRRSV) modified-live virus vaccines analyzing the growth performance in 1-day-old vaccinated swine located on endemic farms co-circulating PRRSV-1 and PRRSV-2.

The objective of this study was to compare the efficacy of a porcine reproductive and respiratory syndrome virus (PRRSV)-1 and PRRSV-2 modified-live virus (MLV) vaccines when administered at 1 day of age under field conditions. The piglets elicited anti-PRRSV antibodies at 1 day of age even in the presence of maternally derived antibodies. The number of PRRSV-2 genomic copies in the sera of pigs from the PRRSV-2 MLV-vaccinated pigs was significantly (P<0.05) lower when compared to PRRSV-1 MLV-vaccinated pigs. The average daily gain in PRRSV-2 MLV-vaccinated pigs was significantly (P<0.05) higher when compared to both PRRSV-1 MLV-vaccinated and unvaccinated pigs. This study demonstrated that vaccination as early as 1 day of age was effective against PRRSV infection.

Evaluation of the efficacy of a trivalent vaccine mixture against a triple challenge with Mycoplasma hyopneumoniae, PCV2, and PRRSV and the efficacy comparison of the respective monovalent vaccines against a single challenge.

BACKGROUND: The objective of this study was to assess the efficacy of a trivalent vaccine mixture and compare it to the respective monovalent vaccines against Mycoplasma hyopneumoniae, porcine circovirus type 2 (PCV2), and porcine reproductive and respiratory syndrome virus (PRRSV). RESULTS: Pigs that were triple challenged with M. hyopneumoniae, PCV2, and PRRSV following vaccination with the trivalent vaccine mixture exhibited a significantly better growth performance when compared to unvaccinated and challenged pigs. A statistical difference was not found when comparing pig populations which were vaccinated with the trivalent vaccine followed by a triple challenge and pigs vaccinated with monovalent M hyopneumoniae vaccine followed by mycoplasmal single challenge in the following areas: M. hyopneumoniae nasal shedding, the number of M. hyopneumoniae-specific interferon-γ secreting cells (IFN-γ-SC), and mycoplasmal lung lesion scores. Pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge resulted in a similar reduction of PCV2 viremia, an increase in the number of PCV2-specific IFN-γ-SC and reduction in interstitial lung lesion scores when compared to pigs vaccinated with a PCV-2 vaccine and challenged with PCV2 only. Lastly, there was a significant difference in the reduction of PRRSV viremia, an increase in PRRSV-specific IFN-γ-SC and a reduction of interstitial lung lesion scores between pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge and pigs vaccinated with a monovalent PRRSV vaccine followed by PRRSV challenge only. CONCLUSION: The trivalent vaccine mixture was efficacious against a triple challenge of M. hyopneumoniae, PCV2, and PRRSV. The trivalent vaccine mixture, however, did not result in equal protection when compared against each respective monovalent vaccine, with the largest vaccine occurring within PRRSV.

Effectiveness of a commercial porcine reproductive and respiratory syndrome virus (PRRSV) subunit vaccine against heterologous PRRSV-1 and PRRSV-2 challenge in late-term pregnant gilts.

The objective of the present study was to evaluate the efficacy of a commercial porcine reproductive and respiratory syndrome virus (PRRSV) subunit vaccine against heterologous PRRSV-1 and PRRSV-2 challenge in late-term pregnant gilts. Gilts were vaccinated intramuscularly 56 and 35 days antepartum (on days 58 and 79 of gestation) and challenged intranasally 21 days antepartum (on day 93 of gestation) with PRRSV-1 or PRRSV-2. Regardless of the challenge strain's genotype, the vaccinated gilts carried their pregnancies to term and farrowed between days 114 and 115 of gestation. All the unvaccinated gilts aborted, between days 105 and 110 of gestation. The vaccinated gilts had a significantly lower level (P < 0.05) of PRRSV viremia and significantly higher levels (P < 0.05) of virus-neutralizing antibodies and interferon-γ-secreting cells compared with the unvaccinated gilts. The mean number of PRRSV-positive cells per area of fetal tissue examined did not differ significantly between the litters from the vaccinated and unvaccinated gilts. The data presented here indicate that vaccination in late-term pregnancy with PRRSV subunit vaccine is efficacious against reproductive failure due to heterologous PRRSV-1 and PRRSV-2 infection.

L'objectif de la présente étude était d'évaluer l'efficacité d'un vaccin sous-unitaire commercial contre le virus du syndrome reproducteur et respiratoire porcin (VSRRP) lors d'une infection défi avec des souches de VSRRP-1 et VSRRP-2 hétérologues chez des cochettes en fin de gestation. Les cochettes furent vaccinées par voie intramusculaire 56 et 35 jours ante-partum (aux jours 58 et 79 de la gestation) et infectées par voie intra-nasale 21 jours ante-partum (jour 93 de la gestation) avec VSRRP-1 ou VSRRP-2. Sans égard au génotype de la souche utilisée pour l'infection défi, les cochettes vaccinées ont mené leur gestation à terme et ont mis-bas entre les jours 114 et 115 de la gestation. Toutes les cochettes non-vaccinées ont avorté, entre les jours 105 et 110 de gestation. Les cochettes vaccinées avaient un niveau significativement plus faible (P < 0,05) de virémie à VSRRP et des niveaux significativement plus élevés (P < 0,05) d'anticorps viraux neutralisants et de cellules secrétant de l'interféron-γ comparativement aux cochettes non-vaccinées. Le nombre moyen de cellules positives pour VSRRP par surface de tissu foetal examiné ne différait pas significativement entre les portées des cochettes vaccinées et non-vaccinées. Les résultats présentés ici indiquent que la vaccination en fin de gestation avec un vaccin sous-unitaire anti-VSRRP est efficace contre les problèmes reproducteurs causés par une infection par des souches hétérologues de VSRRP-1 et VSRRP-2.(Traduit par Docteur Serge Messier).

A comparative study of the efficacy of a porcine reproductive and respiratory syndrome subunit and a modified-live virus vaccine against respiratory diseases in endemic farms.

The efficacy of a porcine reproductive and respiratory syndrome (PRRS) subunit vaccine was evaluated and compared with a modified-live virus (MLV) vaccine under field conditions. Three farms were selected based on their history of respiratory diseases caused by co-infection with both PRRSV-1 and PRRSV-2. In each farm, 60 pigs were randomly allocated to 2 vaccinated and 1 unvaccinated groups (20 pigs per group). One group of pigs were administered the PRRS subunit vaccine at 21 and 42 days of age and another group administered the PRRS MLV vaccine at 21 days of age. The subunit vaccine had similar efficacy and, in some instances, performed even better than the MLV vaccine. Vaccination of pigs with either of the PRRS vaccines resulted in significantly improved growth performance in Farm B but not in Farm C. In Farm A, pigs vaccinated with the PRRS subunit vaccine had a better growth performance statistically compared to those vaccinated with the PRRS MLV vaccine. At the peak of PRRSV-1 and PRRSV-2 viremia, neutralizing antibodies and T-cell responses against PRRSV-1 and PRRSV-2 were at low levels suggesting that either vaccine is only able to provide a partial protection against co-circulating PRRSV-1 and PRRSV-2.

L'efficacité d'un vaccin sous-unitaire contre le syndrome reproducteur et respiratoire porcin (SRRP) a été évaluée et comparée à un vaccin vivant modifié (VVM) dans des conditions de terrain. Trois fermes furent sélectionnées sur la base de leur historique de maladies respiratoires causées par co-infection par VSSRP-1 et VSRRP-2. Sur chaque ferme, 60 porcs furent répartis de manière aléatoire à deux groupes vaccinés et un groupe non-vacciné (20 porcs par groupe). Un groupe de porcs a reçu le vaccin SRRP sous-unitaire à 21 et 42 j d'âge et un autre groupe a reçu le VVM SRRP à 21 j d'âge. Le vaccin sous-unitaire avait une efficacité similaire, et en certaines occasions, performait mieux que le VVM. La vaccination des porcs avec un ou l'autre des vaccins SRRP, a résulté en une amélioration significative des performances de croissance pour la Ferme B mais pas pour la Ferme C. Sur la Ferme A, les porcs vaccinés avec le vaccin sous-unitaire SRRP présentaient de meilleures performances de croissance comparativement à ceux vaccinés avec le VVM du SRRP. Au pic de la virémie de VSRRP-1 et VSRRP-2, les réponses en anticorps neutralisants et en cellules T contre VSRRP-1 et VSRRP-2 étaient faibles ce qui suggère que les deux vaccins ne sont en mesure que de fournir une protection partielle contre une co-infection par VSRRP-1 et VSRRP-2.(Traduit par Docteur Serge Messier).

Comparison of four commercial PRRSV MLV vaccines in herds with co-circulation of PRRSV-1 and PRRSV-2.

The efficacy of four commercial porcine reproductive and respiratory syndrome virus (PRRSV) modified-live virus (MLV) vaccines against respiratory disease was evaluated and compared in pig farms suffering from co-infection with PRRSV-1 and PRRSV-2. All vaccinated groups on average exhibited improved growth rate compared to the unvaccinated pigs. Interestingly, the two groups vaccinated with either of the PRRSV-2 MLV vaccines had a better overall growth rate compared to the pigs vaccinated with either of the PRRSV-1 MLV vaccines. Vaccination of pigs with either of the PRRSV-1 MLV vaccines did not result in reduction of PRRSV-1 or PRRSV-2 viremia whereas vaccination of pigs with either of the PRRSV-2 MLV vaccines resulted in the reduction of PRRSV-2 viremia only. Taken together, the results of this field study demonstrate that a PRRSV-2 MLV vaccine can be efficacious against respiratory disease caused by co-infection with PRRSV-1 and PRRSV-2.

Bioactive calcium phosphate materials and applications in bone regeneration.

BACKGROUND: Bone regeneration involves various complex biological processes. Many experiments have been performed using biomaterials in vivo and in vitro to promote and understand bone regeneration. Among the many biomaterials, calcium phosphates which exist in the natural bone have been conducted a number of studies because of its bone regenerative property. It can be directly contributed to bone regeneration process or assist in the use of other biomaterials. Therefore, it is widely used in many applications and has been continuously studied. MAINBODY: Calcium phosphate has been widely used in bone regeneration applications because it shows osteoconductive and in some cases osteoinductive features. The release of calcium and phosphorus ions regulates the activation of osteoblasts and osteoclasts to facilitate bone regeneration. The control of surface properties and porosity of calcium phosphate affects cell/protein adhesion and growth and regulates bone mineral formation. Properties affecting bioactivity vary depending on the types of calcium phosphates such as HAP, TCP and can be utilized in various applications because of differences in ion release, solubility, stability, and mechanical strength. In order to make use of these properties, different calcium phosphates have been used together or mixed with other materials to complement their disadvantages and to highlight their advantages. Calcium phosphate has been utilized to improve bone regeneration in ways such as increasing osteoconductivity for bone ingrowth, enhancing osteoinductivity for bone mineralization with ion release control, and encapsulating drugs or growth factors. CONCLUSION: Calcium phosphate has been used for bone regeneration in various forms such as coating, cement and scaffold based on its unique bioactive properties and bone regeneration effectiveness. Additionally, several studies have been actively carried out to improve the efficacy of calcium phosphate in combination with various healing agents. By summarizing the properties of calcium phosphate and its research direction, we hope that calcium phosphate can contribute to the clinical treatment approach for bone defect and disease.

Comparison of 4 commercial modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccines against heterologous Korean PRRSV-1 and PRRSV-2 challenge.

The efficacy of 4 commercial porcine reproductive and respiratory syndrome virus (PRRSV) modified-live vaccines (MLV), against PRRSV-1 and PRRSV-2 was evaluated and compared in growing pigs. Two of the vaccines were based on PRRSV-1 and two on PRRSV-2. There were no significant differences between each of the two PRRSV-1 MLV vaccines and the two PRRSV-2 MLV vaccines respectively based on virology, immunological, and pathological evaluations. Vaccination with either of the PRRSV-1 MLV vaccines resulted in reduced PRRSV-1 but not PRRSV-2 viremia. Additionally, vaccination with either of the PRRSV-1 MLV vaccines resulted in reduction of lung lesions and PRRSV-1 positive cells in PRRSV-1 challenged pigs but had no significant effect in PRRSV-2 challenged pigs. In contrast, vaccination with either of the two PRRSV-2 MLV vaccines resulted in the reduction of both PRRSV-1 and PRRSV-2 viremia. The PRRSV-2 MLV vaccines were also able to effectively reduce lung lesions and PRRSV positive cells after challenge with either PRRSV-1 or PRRSV-2. Our data suggest that while vaccination with PRRSV-1 MLV vaccines can be effective against PRRSV-1, only PRRSV-2 MLV vaccines can protect against both Korean PRRSV-1 and PRRSV-2 challenges in this study.

L'efficacité de quatre vaccins vivants modifiés (VVM) commerciaux contre le virus du syndrome reproducteur et respiratoire porcin (VSRRP), a été évaluée et comparée chez des porcs en croissance infectés expérimentalement avec VSRRP-1 et VSRRP-2. Deux des vaccins étaient à base de VSRRP-1 et deux à base de VSRRP-2. Il n'y avait pas de différence significative entre chacun des deux VVM VSRRP-1 et les deux VVM VSRRP-2 respectivement sur la base des évaluations virologiques, immunologiques et pathologiques. La vaccination avec l'un ou l'autre des VVM VSRRP-1 a entrainé une réduction de la virémie causée par VSRRP-1 mais pas par VSRRP-2. De plus, la vaccination avec l'un ou l'autre des VVM VSRRP-1 a permis une réduction des lésions pulmonaires et des cellules positives pour VSRRP-1 chez les porcs infectés avec VSRRP-1 mais n'a pas eu d'effet significatif chez les porcs infectés avec VSRRP-2. La vaccination avec l'un ou l'autre des VVM SRRP-2 a résulté en une réduction de la virémie autant pour VSRRP-1 que VSRRP-2. Les VVM VSRRP-2 étaient également en mesure de réduire efficacement les lésions pulmonaires et les cellules positives pour VSRRP après l'infection soit par le VSRRP-1 ou VSRRP-2. Nos résultats suggèrent que bien que la vaccination avec les VVM VSRRP-1 peuvent être efficaces envers VSRRP-1, seulement les VVM VSRRP-2 peuvent protéger contre les infections par les VSRRP-1 et VSRRP-2 coréens utilisés dans la présente étude.(Traduit par Docteur Serge Messier).

Cross-protection of a modified-live porcine reproductive and respiratory syndrome virus (PRRSV)-2 vaccine against a heterologous PRRSV-1 challenge in late-term pregnancy gilts.

We have evaluated the cross-protection of a modified-live virus (MLV) vaccine based on porcine reproductive and respiratory syndrome virus (PRRSV)-2, against a heterologous PRRSV-1 challenge in late term pregnancy gilts. Gilts were vaccinated 42 days prior to breeding and then challenged intranasally with PRRSV-1 at 93 days of gestation. No local or systemic adverse effects related to vaccination were observed in the vaccinated gilts throughout the study. Vaccination resulted in a longer gestation period, a higher number of live-born and weaned piglets, and a significant decrease in the number of stillborn piglets compared to the unvaccinated group. The PRRSV-2 MLV vaccine was also able to significantly reduce PRRSV-1 viremia. At the time of PRRSV-1 challenge, vaccinated gilts had significantly higher PRRSV-1 specific interferon-γ secreting cells but low neutralizing antibody titers against PRRSV-1 compared to unvaccinated gilts. This correlated with a reduction of PRRSV-1 viremia, indicating that cell-mediated rather than humoral immunity played a role in PRRSV-1 clearance from the blood. Fetal thymic tissues from vaccinated pregnant gilts had fewer PRRSV-1 positive cells compared to unvaccinated gilts. Taken together these results indicate that vaccination of gilts with PRRSV-2 MLV vaccine can provide cross-protection against PRRSV-1 challenge and improve reproductive performance.

Comparative evaluation of the efficacy of commercial and prototype PRRS subunit vaccines against an HP-PRRSV challenge.

The objective of this study was to compare the efficacy of a commercial porcine reproductive and respiratory syndrome (PRRS) subunit vaccine and a prototype PRRS II subunit vaccine against a highly pathogenic PRRS virus (HP-PRRSV) in pigs. Both vaccines were administered intramuscularly in 2 doses at 21 and 42 days of age, and the pigs were challenged intranasally with HP-PRRSV at 63 days of age. Pigs vaccinated with the prototype PRRS II subunit vaccine had significantly higher anti-PRRSV antibody titers, a greater number of interferon-γ-secreting cells, and a greater reduction in lung lesion scores compared to pigs vaccinated with the commercial PRRS subunit vaccine. Therefore, the commercial PRRS subunit and prototype PRRS II subunit vaccines are efficacious against HP-PRRSV.

Visible Light-Erasable Oxide FET-Based Nonvolatile Memory Operated with a Deep Trap Interface.

A new concept of a tunneling oxide-free nonvolatile memory device with a deep trap interface floating gate is proposed. This device demonstrates a high on/off current ratio of 107 and a sizable memory window due to deep traps at the interface between the channel and gate dielectric layers. Interestingly, irradiation with 400 nm light can completely restore the program state to the initial one (performing an erasing process), which is attributed to the visible light-sensitive channel layer. Device reproducibility is enhanced by selectively passivating shallow traps at the interface using in situ H2 plasma treatment. The passivated memory device shows highly reproducible memory operation and on-state current during retention bake tests at 85 °C. One of the most significant advantages of this visible light-erasable oxide field-effect transistor-based nonvolatile memory is its simple structure, which is free from deterioration due to the frequent tunneling processes, as compared to conventional nonvolatile memory devices with tunneling oxides.

A comparison of the severity of reproductive failure between single and dual infection with porcine reproductive and respiratory syndrome virus (PRRSV)-1 and PRRSV-2 in late-term pregnancy gilts.

The objective of this study was to compare the severity of reproductive failure caused by either a single or a dual infection with porcine reproductive and respiratory syndrome virus (PRRSV)-1 and PRRSV-2 in late-term pregnancy gilts. Pregnant gilts were intranasally administered PRRSV-1, PRRSV-2 or both at 3 weeks before the expected farrowing date (93 days of gestation). Regardless of single and dual infection, PRRSV-infected pregnant gilts experienced premature farrowing (103-109 days of gestation) compared with negative control gilts which carried their pregnancy to full term (114-115 days of gestation). Pregnant gilts infected with only PRRSV-1 had a significantly (p < 0.05) higher number of genomic copies of PRRSV-1 in their blood compared with dually infected gilts. Additionally, stillborn foetuses and live-born piglets from pregnant gilts infected with only PRRSV-1 had a significantly (p < 0.05) higher number of PRRSV-1-positive cells per unit area of tissue sections examined, compared to pregnant gilts dually infected with PRRSV-1 and PRRSV-2. In contrast, pregnant gilts infected with only PRRSV-2 showed no difference in the number of genomic copies of PRRSV-2 compared with dually infected pregnant gilts and there were no significant differences in PRRSV-2-positive cells per unit area in tissues of stillborn foetuses and live-born piglets from pregnant gilts infected with PRRSV-2 only compared with dually infected gilts. Interestingly, even though PRRSV-2 was shown to replicate more efficiently compared with PRRSV-1 in dually infected pregnant gilts, neither PRRSV type was able to exacerbate reproductive failure in pregnant gilts already dually infected with PRRSV-1 and PRRSV-2. Our results suggest that the severity of reproductive failure is similar between dual (PRRSV-1 and PRRSV-2) and single infection (PRRSV-1 or PRRSV-2).

Evaluation of the efficacy of a novel porcine circovirus type 2 synthetic peptide vaccine.

A novel porcine circovirus type 2 (PCV2) peptide vaccine comprised of a consensus capsid (Cap) protein domain encoded by open reading frame 2 was developed to control PCV2 infection. The efficacy of the vaccine was evaluated against a commercial baculovirus-expressed recombinant PCV2 subunit vaccine based on the Cap protein. The amino acid sequence of this Cap protein was designed based on the alignment of amino acid sequences from different isolates from Europe, North America, and Asia. The vaccine was evaluated in either phosphate-buffered saline or adjuvanted with aluminum hydroxide, cobalt oxide, or liposome. Overall the PCV2 peptide vaccine was less efficacious against PCV2 challenge compared with the commercial PCV2 vaccine. The peptide vaccine was the most efficacious when liposome was used as an adjuvant, significantly (P < 0.05) reducing viremia while increasing the levels of neutralizing antibodies and interferon-γ secreting cells. This suggests, in the presence of liposome, the peptide vaccine was able to elicit both humoral and cellular immune responses.

Un nouveau vaccin peptidique contre le circovirus porcin de type 2 (CVP2) contenant un domaine d'une protéine consensus de la capside (Cap) codé par le cadre de lecture ouvert 2 fut développé pour limiter l'infection par CVP2. L'efficacité du vaccin fut évaluée versus celle d'un vaccin commercial CVP2 sous-unitaire recombinant s'exprimant dans un baculovirus et basé sur la protéine Cap. La séquence en acides aminés de cette protéine Cap a été élaborée basée sur l'alignement des séquences d'acides aminés provenant de différents isolats d'Europe, d'Amérique du Nord, et d'Asie. Le vaccin a été évalué dans soit de la saline tamponnée avec du phosphate ou dans un adjuvant contenant de l'hydroxyde d'aluminium, d'oxyde de cobalt, ou des liposomes. Globalement, le vaccin peptidique CVP2 était moins efficace contre une infection défi par CVP2 comparativement au vaccin commercial. Le vaccin peptidique était le plus efficace lorsque les liposomes étaient utilisés comme adjuvant, réduisant de manière significative (P < 0,05) la virémie tout en augmentant la quantité d'anticorps neutralisants et de cellules secrétant de l'interféron γ. Ceci suggère qu'en présence de liposomes le vaccin lipidique était en mesure d'induire des réponses immunitaires humorale et cellulaire.(Traduit par Docteur Serge Messier).

Effect of vaccination with a porcine reproductive and respiratory syndrome subunit vaccine on sow reproductive performance in endemic farms.

The objective of this field study was to evaluate the reproductive performance of sows after vaccination with a porcine reproductive and respiratory syndrome (PRRS) subunit vaccine (PRRSFREE PRRS subunit vaccine, Reber Genetics, Taiwan, Republic of China) under field conditions. The study was performed in three farms with endemic infections with both PRRS virus (PRRSV)-1 and PRRSV-2, a situation representative of most Korean farms. Pregnant sows were immunised intramuscularly with 2.0 ml of the PRRS subunit vaccine at 58 and 79 days of gestation (eight and five weeks antepartum) according to the manufacturer's recommendation. Vaccination did not result in any observed adverse reaction. Vaccinated sows exhibited a significant improvement in reproductive performance (reduction of abortions) and litter characteristics (increase of weaned pigs) compared with unvaccinated sows. Vaccinated sows had significantly (P<0.05) higher PRRSV ELISA sample/positive ratio and number of PRRSV-specific interferon-γ-secreting cells compared with the unvaccinated control group. The results of this study demonstrate that the PRRS subunit vaccine can improve the reproductive performance of sows in farms with endemic PRRSV infection.