Knee Joint Competence Post Anterior Cruciate Ligament Reconstruction in Amateur South Western Districts Rugby Players

Background: Globally, literature has shown that rugby players struggle to return to the same level of performance post anterior cruciate ligament (ACL) reconstruction. This phenomenon is further exacerbated amongst South African Rugby players, compounded by the ranking of the national team amongst the top ten rugby teams worldwide. Paired with the psychosocial aspect of return to play, the physical and physiological competence of the knee joint is of pivotal importance. Purpose: To compare relative dynamic stability scores paired with electromyography (EMG) scores between the injured and uninjured legs, thereby enabling an explorative, descriptive report on dynamic proprioceptive abilities post ACL reconstruction (ACLR). The study findings therefore aim to inform rehabilitative practice in a rugby player who underwent ACLR. Study Design: A quantitative, explorative and descriptive design was used, with a purposive sampling strategy. Methods: Biographical and anthropometrical data was measured upon inception. Muscular activation was measured using electromyography (EMG) placements on quadriceps muscles which included the vastus medialis obliques (VMO), and vastus lateralis (VL). Dynamic proprioception was measured using the star excursion balance test (SEBT) and normalised to leg length. A neuromuscular fatigue protocol was used to measure the impact of neuromuscular fatigue on dynamic stability, and muscle activation between the injured and uninjured lower limbs. Results: A sample of 15 participants from the South Western Districts (SWD) rugby team, fitting the inclusion criteria, were included in the study. The average age was 27±2.7 years. The results indicated that fatigue did not significantly affect the SEBT scores between the injured and uninjured lower limbs. However, the VMO muscle activation showed a statistically significant difference in muscle firing in a pre-fatigue state. This difference was evident in two of the eight directions namely anteromedial direction (p = 0.041), and in the lateral direction (p = 0.047). Furthermore, these result differences were favoured in the uninjured limb. No significant differences between the injured and uninjured lower limbs were found in respect to VMO and VL muscle activation, in a fatigued state. vi Conclusion: Practically translated, the study results showed that the injured lower limb, showed no significant differences in dynamic stability during both the non-fatigued and the fatigued SEBT. Therefore, the finding of this study is a steppingstone towards informing return to play criteria for adequate dynamic knee stability and proprioception. It should be noted that further research is necessary to refine return to play criteria and thereby decrease the risk for re-injury. Keywords: anterior cruciate ligament; dynamic stability; neuro-muscular fatigue; reconstruction; re-injury; return-to-sport; rugby.Thesis (MA) -- Faculty of Health Sciences, 202

Knee Joint Competence Post Anterior Cruciate Ligament Reconstruction in Amateur South Western Districts Rugby Players

Background: Globally, literature has shown that rugby players struggle to return to the same level of performance post anterior cruciate ligament (ACL) reconstruction. This phenomenon is further exacerbated amongst South African Rugby players, compounded by the ranking of the national team amongst the top ten rugby teams worldwide. Paired with the psychosocial aspect of return to play, the physical and physiological competence of the knee joint is of pivotal importance. Purpose: To compare relative dynamic stability scores paired with electromyography (EMG) scores between the injured and uninjured legs, thereby enabling an explorative, descriptive report on dynamic proprioceptive abilities post ACL reconstruction (ACLR). The study findings therefore aim to inform rehabilitative practice in a rugby player who underwent ACLR. Study Design: A quantitative, explorative and descriptive design was used, with a purposive sampling strategy. Methods: Biographical and anthropometrical data was measured upon inception. Muscular activation was measured using electromyography (EMG) placements on quadriceps muscles which included the vastus medialis obliques (VMO), and vastus lateralis (VL). Dynamic proprioception was measured using the star excursion balance test (SEBT) and normalised to leg length. A neuromuscular fatigue protocol was used to measure the impact of neuromuscular fatigue on dynamic stability, and muscle activation between the injured and uninjured lower limbs. Results: A sample of 15 participants from the South Western Districts (SWD) rugby team, fitting the inclusion criteria, were included in the study. The average age was 27±2.7 years. The results indicated that fatigue did not significantly affect the SEBT scores between the injured and uninjured lower limbs. However, the VMO muscle activation showed a statistically significant difference in muscle firing in a pre-fatigue state. This difference was evident in two of the eight directions namely anteromedial direction (p = 0.041), and in the lateral direction (p = 0.047). Furthermore, these result differences were favoured in the uninjured limb. No significant differences between the injured and uninjured lower limbs were found in respect to VMO and VL muscle activation, in a fatigued state. vi Conclusion: Practically translated, the study results showed that the injured lower limb, showed no significant differences in dynamic stability during both the non-fatigued and the fatigued SEBT. Therefore, the finding of this study is a steppingstone towards informing return to play criteria for adequate dynamic knee stability and proprioception. It should be noted that further research is necessary to refine return to play criteria and thereby decrease the risk for re-injury. Keywords: anterior cruciate ligament; dynamic stability; neuro-muscular fatigue; reconstruction; re-injury; return-to-sport; rugby.Thesis (MA) -- Faculty of Health Sciences, 202

African horse sickness virus NS4 is a nucleocytoplasmic protein that localizes to PML nuclear bodies

African horse sickness virus (AHSV) is the causative agent of the often fatal disease African horse sickness in equids. The non-structural protein NS4 is the only AHSV protein that localizes to the nucleus. Here we report that all AHSV reference and representative field strains express one of the two forms of NS4, i.e. NS4-I or NS4-II. Both forms of NS4 are nucleocytoplasmic proteins, but NS4-I has a stronger nuclear presence whilst NS4-II has a proportionally higher cytoplasmic distribution. A subtype of NS4-II containing a nuclear localization signal (NLS), named NLS-NS4-II, displays distinct punctate foci in the nucleus. We showed that NS4 likely enters the nucleus via passive diffusion as a result of its small size. Colocalization analysis with nuclear compartments revealed that NS4 colocalizes with promyelocytic leukaemia nuclear bodies (PML-NBs), suggesting a role in the antiviral response or interferon signalling. Interestingly, we showed that two other AHSV proteins also interact with nuclear components. A small fraction of the NS1 tubules were present in the nucleus and associated with PML-NBs; this was more pronounced for a virus strain lacking NS4. A component of nuclear speckles, serine and arginine rich splicing factor 2 (SRSF2) was recruited to viral inclusion bodies (VIBs) in the cytoplasm of AHSV-infected cells and colocalized with NS2. Nuclear speckles are important sites for cellular mRNA transcript processing and maturation. Collectively, these results provide data on three AHSV non-structural proteins interacting with host cell nuclear components that could contribute to overcoming antiviral responses and creating conditions that will favour viral replication.http://jgv.microbiologyresearch.org/content/journal/jgvhj2020BiochemistryGeneticsMicrobiology and Plant Patholog

Investigating the role of African horse sickness virus VP7 protein crystalline particles on virus replication and release

African horse sickness is a deadly and highly infectious disease of equids, caused by African horse sickness virus (AHSV). AHSV is one of the most economically important members of the Orbivirus genus. AHSV is transmitted by the biting midge, Culicoides, and therefore replicates in both insect and mammalian cell types. Structural protein VP7 is a highly conserved major core protein of orbiviruses. Unlike any other orbivirus VP7, AHSV VP7 is highly insoluble and forms flat hexagonal crystalline particles of unknown function in AHSV-infected cells and when expressed in mammalian or insect cells. To examine the role of AHSV VP7 in virus replication, a plasmid-based reverse genetics system was used to generate a recombinant AHSV that does not form crystalline particles. We characterised the role of VP7 crystalline particle formation in AHSV replication in vitro and found that soluble VP7 interacted with viral proteins VP2 and NS2 similarly to wild-type VP7 during infection. Interestingly, soluble VP7 was found to form uncharacteristic tubule-like structures in infected cells which were confirmed to be as a result of unique VP7-NS1 colocalisation. Furthermore, it was found that VP7 crystalline particles play a role in AHSV release and yield. This work provides insight into the role of VP7 aggregation in AHSV cellular pathogenesis and contributes toward the understanding of the possible effects of viral protein aggregation in other human virus-borne diseases.https://www.mdpi.com/journal/virusesdm2022Biochemistr

Unusual Assortment of Segments in 2 Rare Human Rotavirus Genomes

Using full-length genome sequence analysis, we investigated 2 rare G3P[9] human rotavirus strains isolated from children with diarrhea. The genomes were recognized as assortments of genes closely related to rotaviruses originating from cats, ruminants, and humans. Results suggest multiple transmissions of genes from animal to human strains of rotaviruses

Establishment of different plasmid only-based reverse genetics systems for the recovery of African horse sickness virus

In an effort to simplify and expand the utility of African horse sickness virus (AHSV) reverse genetics, different plasmid-based reverse genetics systems were developed. Plasmids containing cDNAs corresponding to each of the full-length double-stranded RNA genome segments of AHSV-4 under control of a T7 RNA polymerase promoter were co-transfected in cells expressing T7 RNA polymerase, and infectious AHSV-4 was recovered. This reverse genetics system was improved by reducing the required plasmids from 10 to five and resulted in enhanced virus recovery. Subsequently, a T7 RNA polymerase expression cassette was incorporated into one of the AHSV-4 rescue plasmids. This modified 5-plasmid set enabled virus recovery in BSR or L929 cells, thus offering the possibility to generate AHSV-4 in any cell line. Moreover, mutant and cross-serotype reassortant viruses were recovered. These plasmid DNA-based reverse genetics systems thus offer new possibilities for investigating AHSV biology and development of designer AHSV vaccine strainsThis work was supported by the University of Pretoria’s Institutional Research Theme Programme (Grant AOU999), Poliomyelitis Research Foundation (Grant 13/19) and the Technology Innovation Agency (Grant TAHC12-00028). Graduate bursary (AMC) and postdoctoral fellowship (LS) support was received from the National Research Foundation and the Poliomyelitis Research Foundation.http://www.elsevier.com/locate/yviro2017-12-31hb2016GeneticsMicrobiology and Plant Patholog

Isolation and Phylogenetic Grouping of Equine Encephalosis Virus in Israel

During 2008–2009 in Israel, equine encephalosis virus (EEV) caused febrile outbreaks in horses. Phylogenetic analysis of segment 10 of the virus strains showed that they form a new cluster; analysis of segment 2 showed ≈92% sequence identity to EEV-3, the reference isolate. Thus, the source of this emerging EEV remains uncertain

African horse sickness virus NS4 protein is an important virulence factor and interferes with JAK-STAT signaling during viral infection

African horse sickness virus (AHSV) non-structural protein NS4 is a nucleocytoplasmic protein that is expressed in the heart, lung, and spleen of infected horses, binds dsDNA, and colocalizes with promyelocytic leukemia nuclear bodies (PML-NBs). The aim of this study was to investigate the role of AHSV NS4 in viral replication, virulence and the host immune response. Using a reverse genetics-derived virulent strain of AHSV-5 and NS4 deletion mutants, we showed that knockdown of NS4 expression has no impact in cell culture, but results in virus attenuation in infected horses. RNA sequencing (RNA-seq) was used to investigate the transcriptional response in these horses, to see how the lack of NS4 mediates the transition of the virus from virulent to attenuated. The presence of NS4 was shown to result in a 24 hour (h) delay in the transcriptional activation of several immune system processes compared to when the protein was absent. Included in these processes were the RIG-I-like, Toll-like receptor, and JAK-STAT signaling pathways, which are key pathways involved in innate immunity and the antiviral response. Thus, it was shown that AHSV NS4 suppresses the host innate immune transcriptional response in the early stages of the infection cycle. We investigated whether AHSV NS4 affects the innate immune response by impacting the JAK-STAT signaling pathway specifically. Using confocal laser scanning microscopy (CLSM) we showed that AHSV NS4 disrupts JAK-STAT signaling by interfering with the phosphorylation and/or translocation of STAT1 and pSTAT1 into the nucleus. Overall, these results showed that AHSV NS4 is a key virulence factor in horses and allows AHSV to overcome host antiviral responses in order to promote viral replication and spread.SUPPLEMENTARY MATERIAL: Supplementary table 1: Full list of differentially expressed genes in the transcriptome analysis. The genes were sorted according to log2Fold change values and then grouped according to up- or down-regulated genes. Days 1, 2 and 4 are presented for the horse inoculated with rAHSV-5 (NS4) and days 1 and 2 for the horses inoculated with rAHSV-5minNS4 (minNS4). The log2FC is indicated in bold for genes differentially expressed on the same day in both NS4 and minNS4. aRanks of up- or down-regulated genes in each comparison. *Involved in innate immunity according to InnateDB.Supplementary table 2: Full list of KEGG pathways enriched by the differentially expressed genes in the transcriptome analysis. The data is displayed per day and includes the up- and down- regulated genes enriching each pathway. Pathways were sorted based on corrected P-value. Days 1, 2 and 4 are presented for the horse inoculated with rAHSV-5 (NS4) and days 1 and 2 for the horses inoculated with rAHSV-5minNS4 (minNS4).Supplementary Figure 1: Images obtained from post-mortem examination of horses inoculated with rAHSV-5. Classical lesions of disease such as frothing from the nostrils (a), interstitial and subpleural lung edema (b, e), alveolar edema (c, f) and hydropericardium (d, g) were observed.Deltamune (Pty) Ltd, the University of Pretoria Institutional Research Themes, the Poliomyelitis Research Foundation, South Africa and the Genomics Research Institute, University of Pretoria. Postgraduate support was received from the Poliomyelitis Research Foundation, South Africa, the National Research Foundation, South Africa and the University of Pretoria, South Africa.http://www.elsevier.com/locate/virusreshj2022BiochemistryGeneticsMicrobiology and Plant Patholog

Complete molecular genome analyses of equine rotavirus a strains from different continents reveal several novel genotypes and a largely conserved genotype constellation

In this study, the complete genome sequences of seven equine group A rotavirus (RVA) strains (RVA/Horse-tc/GBR/L338/1991/G13P[18], RVA/Horse-wt/IRL/03V04954/2003/G3P[12] and RVA/Horse-wt/IRL/04V2024/2004/G14P[12] from Europe; RVA/Horse-wt/ARG/E30/1993/ G3P[12], RVA/Horse-wt/ARG/E403/2006/G14P[12] and RVA/Horse-wt/ARG/E4040/2008/ G14P[12] from Argentina; and RVA/Horse-wt/ZAF/EqRV-SA1/2006/G14P[12] from South Africa) were determined. Multiple novel genotypes were identified and genotype numbers were assigned by the Rotavirus Classification Working Group: R9 (VP1), C9 (VP2), N9 (NSP2), T12 (NSP3), E14 (NSP4), and H7 and H11 (NSP5). The genotype constellation of L338 was unique: G13-P[18]-I6- R9-C9-M6-A6-N9-T12-E14-H11. The six remaining equine RVA strains showed a largely conserved genotype constellation: G3/G14-P[12]-I2/I6-R2-C2-M3-A10-N2-T3-E2/E12-H7, which is highly divergent from other known non-equine RVA genotype constellations. Phylogenetic analyses revealed that the sequences of these equine RVA strains are related distantly to nonequine RVA strains, and that at least three lineages exist within equine RVA strains. A small number of reassortment events were observed. Interestingly, the three RVA strains from Argentina possessed the E12 genotype, whereas the three RVA strains from Ireland and South Africa possessed the E2 genotype. The unusual E12 genotype has until now only been described in Argentina among RVA strains collected from guanaco, cattle and horses, suggesting geographical isolation of this NSP4 genotype. This conserved genetic configuration of equine RVA strains could be useful for future vaccine development or improvement of currently used equine RVA vaccines.Fil: Matthijnssens, Jelle. Katholikie Universiteit Leuven; BélgicaFil: Miño, Orlando Samuel. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Papp, Hajnalka. Hungarian Academy of Sciences; HungríaFil: Potgieter, Christiaan. Ondersterpoort Veterinary Institute; SudáfricaFil: Novo, Luis. Katholikie Universiteit Leuven; BélgicaFil: Heylen, Elisabeth. Katholikie Universiteit Leuven; BélgicaFil: Zeller, Mark. Katholikie Universiteit Leuven; BélgicaFil: Garaicoechea, Lorena Laura. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Badaracco, Alejandra. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lengyel, György. Dr György Radó Military Medical Centre; HungríaFil: Kisfali, Péter. University Of Pécs; HungríaFil: Cullinane, Ann. Irish Equine Centre; IrlandaFil: Collins, P. J.. Cork Ins Of Technology; IrlandaFil: Ciarlet, Max. Novartis Vaccines and Diagnostics; Estados UnidosFil: O'Shea, Helen. Cork Ins Of Technology; IrlandaFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bányai, Krisztián. Hungarian Academy of Sciences; HungríaFil: Barrandeguy, María Edith. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Van Ranst, Marc. Katholikie Universiteit Leuven; Bélgic

Genetic characterisation of South African and Mozambican bovine rotaviruses reveals a typical bovine-like artiodactyl constellation derived through multiple reassortment events

This study presents whole genomes of seven bovine rotavirus strains from South Africa and Mozambique. Double-stranded RNA, extracted from stool samples without prior adaptation to cell culture, was used to synthesise cDNA using a self-annealing anchor primer ligated to dsRNA and random hexamers. The cDNA was subsequently sequenced using an Illumina MiSeq platform without prior genome amplification. All strains exhibited bovine-like artiodactyl genome constellations (G10/G6-P[11]/P[5]-I2-R2-C2-M2-A3/A11/A13-N2-T6-E2-H3). Phylogenetic analysis revealed relatively homogenous strains, which were mostly related to other South African animal strains or to each other. It appears that these study strains represent a specific bovine rotavirus population endemic to Southern Africa that was derived through multiple reassortment events. While one Mozambican strain, MPT307, was similar to the South African strains, the second strain, MPT93, was divergent from the other study strains, exhibiting evidence of interspecies transmission of the VP1 and NSP2 genes. The data presented in this study not only contribute to the knowledge of circulating African bovine rotavirus strains, but also emphasise the need for expanded surveillance of animal rotaviruses in African countries in order to improve our understanding of rotavirus strain diversity.Deutsche Forschungsgemeinschaft (DFG); European Foundation Initiative for African Research into Neglected Tropical Diseases (EFINTD); South African Medical Research Council (SAMRC); Australian National Health and Medical Research Council.http://www.mdpi.com/journal/pathogenspm2022Medical Virolog