bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Cytomegalovirus UL97 Kinase and Nonkinase Functions Mediate Viral Cytoplasmic Secondary Envelopment
Authors: Goldberg Miri D. , Honigman Alik , Weinstein Jacob , Chou Sunwen , Taraboulos Albert , Rouvinski Alexander , Shinder Vera , Wolf Dana G. 
Published: January 2011

ABSTRACT

Previous studies have revealed critical roles for the human cytomegalovirus (HCMV) UL97 kinase in viral nuclear maturation events. We have shown recently that UL97 affects the morphology of the viral cytoplasmic assembly compartment (AC) (M. Azzeh, A. Honigman, A. Taraboulos, A. Rouvinski, and D. G. Wolf, Virology
354:
69-79, 2006). Here, we employed a comprehensive ultrastructural analysis to dissect the impact of UL97 on cytoplasmic steps of HCMV assembly. Using UL97 deletion (ΔUL97) and kinase-null (K355M) mutants, as well as the UL97 kinase inhibitor NGIC-I, we demonstrated that the loss of UL97 kinase activity resulted in a unique combination of cytoplasmic features: (i) the formation of pp65-rich aberrant cytoplasmic tegument aggregates, (ii) distorted intracytoplasmic membranes, which replaced the normal architecture of the AC, and (iv) a paucity of cytoplasmic tegumented capsids and dense bodies (DBs). We further showed that these abnormal assembly intermediates did not result from impaired nuclear capsid maturation and egress
per se
by using 2-bromo-5,6-dichloro-1-(β-
d
-ribofuranosyl) benzimidizole (BDCRB) to induce the artificial inhibition of nuclear maturation and the nucleocytoplasmic translocation of capsids. The specific abrogation of UL97 kinase activity under low-multiplicity-of-infection conditions resulted in the improved release of extracellular virus compared to that of ΔUL97, despite similar rates of viral DNA accumulation and similar effects on nuclear capsid maturation and egress. The only ultrastructural correlate of the growth difference was a higher number of cytoplasmic DBs, tegumented capsids, and clustered viral particles observed upon the specific abrogation of UL97 kinase activity compared to that of ΔUL97. These combined findings reveal a novel role for UL97 in HCMV cytoplasmic secondary envelopment steps, with a further distinction of kinase-mediated function in the formation of the virus-induced AC and a nonkinase function enhancing the efficacy of viral tegumentation and release.
ALIX/AIP1 Is Required for NP Incorporation into Mopeia Virus Z-Induced Virus-Like Particles
Authors: Shtanko Olena , Watanabe Shinji , Jasenosky Luke D. , Watanabe Tokiko , Kawaoka Yoshihiro 
Published: January 2011

ABSTRACT
During virus particle assembly, the arenavirus nucleoprotein (NP) associates with the viral genome to form nucleocapsids, which ultimately become incorporated into new virions at the cell membrane. Virion release is facilitated by the viral matrix Z protein through its interaction with the cellular endosomal sorting complex required for transport (ESCRT) machinery. However, the mechanism of nucleocapsid incorporation into virions is not well understood. Here, we demonstrate that ALIX/AIP1, an ESCRT-associated host protein, is required for the incorporation of the NP of Mopeia virus, a close relative of Lassa virus, into Z-induced virus-like particles (VLPs). Furthermore, we show that the Bro1 domain of ALIX/AIP1 interacts with the NP and Z proteins simultaneously, facilitating their interaction, and we identify residues 342 to 399 of NP as being necessary for its interaction with ALIX/AIP1. Our observations suggest a potential role for ALIX/AIP1 in linking Mopeia virus NP to Z and the budding apparatus, thereby promoting NP incorporation into virions.
Processing and Localization of the African Swine Fever Virus CD2v Transmembrane Protein
Authors: Goatley Lynnette C. , Dixon Linda K. 
Published: January 2011

ABSTRACTThe African swine fever virus (ASFV)-encoded CD2v transmembrane protein is required for the hemadsorption of red blood cells around infected cells and is also required for the inhibition of bystander lymphocyte proliferation in response to mitogens. We studied the expression of CD2v by expressing the gene with a V5 tag downstream from the signal peptide near the N terminus and a hemagglutinin (HA) tag at the C terminus. In ASFV-infected cells, a full-length glycosylated form of the CD2v protein, which migrated mainly as a 89-kDa product, was detected, as well as an N-terminal glycosylated fragment of 63 kDa and a C-terminal nonglycosylated fragment of 26 kDa. All of these forms of the protein were localized in the membrane fraction of cells. The 26-kDa C-terminal fragment was also produced in infected cells treated with brefeldin A. These data indicate that the CD2v protein is cleaved within the luminal domain and that this occurs in the endoplasmic reticulum or Golgi compartments. Confocal microscopy showed that most of the expressed CD2v protein was localized within cells rather than at the cell surface. Comparison of the localization of full-length CD2v with that of a deletion mutant lacking all of the cytoplasmic tail apart from the 12 membrane-proximal amino acids indicated that signals within the cytoplasmic tail are responsible for the predominant localization of the full-length and C-terminal 26-kDa fragment within membranes around the virus factories, which contain markers for the Golgi compartment. Processing of the CD2v protein was not observed in uninfected cells, indicating that it is induced by ASFV infection.
Antigen-Specific T-Cell Responses to a Recombinant Fowlpox Virus Are Dependent on MyD88 and Interleukin-18 and Independent of Toll-Like Receptor 7 (TLR7)- and TLR9-Mediated Innate Immune Recognition
Authors: Lousberg Erin L. , Diener Kerrilyn R. , Fraser Cara K. , Phipps Simon , Foster Paul S. , Chen Weisan , Uematsu Satoshi , Akira Shizuo , Robertson Sarah A. , Brown Michael P. , Hayball John D. 
Published: January 2011

ABSTRACTFowlpox virus (FWPV) is a double-stranded DNA virus long used as a live-attenuated vaccine against poultry diseases, but more recent interest has focused on its use as a mammalian vaccine vector. Here, in a mouse model system using FWPV encoding the nominal target antigen chicken ovalbumin (OVA) (FWPVOVA), we describe for the first time some of the fundamental processes by which FWPV engages both the innate and adaptive immune systems. We show that Toll-like receptor 7 (TLR7) and TLR9 are important for type I interferon secretion by dendritic cells, while TLR9 is solely required for proinflammatory cytokine secretion. Despite this functional role for TLR7 and TLR9in vitro, only the adapter protein myeloid differentiation primary response gene 88 (MyD88) was shown to be essential for the formation of adaptive immunity to FWPVOVAin vivo. The dependence on MyD88 was confined only to the T-cell compartment and was not related to its contribution to TLR signaling, dendritic cell maturation, or the capture and presentation of FWPV-derived OVA antigen. We demonstrate that this is not by means of mediating T-cell-dependent interleukin-1 (IL-1) signaling, but rather, we suggest that MyD88 functions to support T-cell-specific IL-18 receptor signaling, which in turn is essential for the formation of adaptive immunity to FWPV-encoded OVA.
Src Kinase Mediates Productive Endocytic Sorting of Reovirus during Cell Entry
Authors: Mainou Bernardo A. , Dermody Terence S. 
Published: January 2011

ABSTRACT
Reovirus cell entry is initiated by viral attachment to cell surface glycans and junctional adhesion molecule A. Following receptor engagement, reovirus is internalized into cells by receptor-mediated endocytosis using a process dependent on β1 integrin. Endocytosed virions undergo stepwise disassembly catalyzed by cathepsin proteases, followed by endosomal membrane penetration and delivery of transcriptionally active core particles into the cytoplasm. Cellular factors that mediate reovirus endocytosis are poorly defined. We found that both genistein, a broad-spectrum tyrosine kinase inhibitor, and PP2, a specific Src-family kinase inhibitor, diminish reovirus infectivity by blocking a cell entry step. Although neither inhibitor impedes internalization of reovirus virions, both inhibitors target virions to lysosomes. Reovirus colocalizes with Src during cell entry, and reovirus infection induces phosphorylation of Src at the activation residue, tyrosine 416. Diminished Src expression by RNA interference reduces reovirus infectivity, suggesting that Src is required for efficient reovirus entry. Collectively, these data provide evidence that Src kinase is an important mediator of signaling events that regulate the appropriate sorting of reovirus particles in the endocytic pathway for disassembly and cell entry.
Cellular Gene Expression That Correlates with EBER Expression in Epstein-Barr Virus-Infected Lymphoblastoid Cell Lines
Authors: Gregorovic Goran , Bosshard Rachel , Karstegl Claudio Elgueta , White Robert E. , Pattle Samuel , Chiang Alan K. S. , Dittrich-Breiholz Oliver , Kracht Michael , Russ Rainer , Farrell Paul J. 
Published: January 2011

ABSTRACT
Novel Epstein-Barr Virus (EBV) strains with deletion of either EBER1 or EBER2 and corresponding revertant viruses were constructed and used to infect B lymphocytes to make lymphoblastoid cell lines (LCLs). The LCLs were used in microarray expression profiling to identify genes whose expression correlates with the presence of EBER1 or EBER2. Functions of regulated genes identified in the microarray analysis include membrane signaling, regulation of apoptosis, and the interferon/antiviral response. Although most emphasis has previously been given to EBER1 because it is more abundant than EBER2, the differences in cell gene expression were greater with EBER2 deletion. In this system, deletion of EBER1 or EBER2 had little effect on the EBV transformation frequency of primary B cells or the growth of the resulting LCLs. Using the recombinant viruses and novel EBER expression vectors, the nuclear redistribution of rpL22 protein by EBER1 in 293 cells was confirmed, but in LCLs almost all of the cells had a predominantly cytoplasmic expression of this ribosomal protein, which was not detectably changed by EBER1. The changes in LCL gene expression identified here will provide a basis for identifying the mechanisms of action of EBER RNAs.
M062 Is a Host Range Factor Essential for Myxoma Virus Pathogenesis and Functions as an Antagonist of Host SAMD9 in Human Cells
Authors: Liu Jia , Wennier Sonia , Zhang Leiliang , McFadden Grant 
Published: January 2011

ABSTRACT

Myxoma virus (MYXV) M062R is a functional homolog of the C7L family of host range genes from orthopoxviruses. We constructed a targeted M062R-knockout-MYXV (vMyxM062-KO) and characterized its properties
in vitro
and
in vivo
. In European rabbits, infection by vMyxM062-KO was completely asymptomatic. The surviving rabbits did not gain full protection against the subsequent lethal-dose challenge with wild-type MYXV. We also looked for cellular tropism defects in a variety of cultured cells. In all of the rabbit cells tested, vMyxM062-KO conducts an abortive infection, although it initiates viral DNA replication. In many, but not all, human cancer cells that are permissive for wild-type MYXV, vMyxM062-KO exhibited a profound replication defect. We categorized human cells tested into two groups: (i) type A, which support productive replication for wild-type MYXV but are unable to produce significant levels of progeny virus by vMyxM062-KO, and (ii) type B, which are permissive to infections by both wild-type MYXV and vMyxM062-KO. Furthermore, using proteomic strategies, we identified sterile α motif domain containing 9 (SAMD9), an interferon-regulated cellular protein implicated in human inflammatory disorders, as a unique host binding partner of M062 in human cells. Significantly, knocking down SAMD9 in type A human cancer cells led to a substantial rescue of vMyxM062-KO infection. In summary, M062 is a novel host range factor that controls productive MYXV replication in rabbit cells and in a wide variety of human cells. M062 also binds and antagonizes cellular SAMD9 in human cells, suggesting that SAMD9 is a novel innate antiviral factor against poxviruses.
Why be active?: a qualitative study on the attitudes and beliefs concerning exercise of 11–14 year old school children in slough
Authors: Dosanjh A , Hemmings S , Morrissey D 
Published: January 2011

RationaleObesity is a growing problem in the UK. The problem of obesity is also affecting children and with that come significant health, social and economic concerns. Lack of physical activity in children is evident. Physical activity is also beneficial for tackling obesity as well as other positive health and lifestyle outcomes.AimsWe aim to investigate what children understand by the term exercise and what facilitates and prevents them from being active or taking part in sport and exercise.Subjects and methodologyQualitiative study using focus groups in 11–14 year old school children in Slough to identify their attitudes and beliefs towards exercise. Children were selected from a local slough grammar school.ResultsSeveral themes were identified which were facilatitive or perceived as barriers towards exercise. It was interesting to further discover differences in the barriers between the female and male groups and participants from ethnic minorities.ConclusionBy understanding the beliefs and attitudes towards exercise of 11–14 year old children in Slough we may be able to develop and improve behavioural interventions to encourage exercise in this group. Further study into the barriers and facilitators of adolescent girls and ethnic minority children may be important to develop participation of the groups in physical activity.
Structural changes in the achilles tendon in response to a marathon: ultrasonographically detectable changes immediately and at 2 weeks postmarathon
Authors: Tardioli A 
Published: January 2011

BackgroundThe Achilles tendon undergoes prolonged, repetitive, submaximal loading during endurance running. The acute effects of endurance running on the Achilles tendon are unclear.HypothesisStructural abnormalities and Doppler flow are common in highly trained endurance runners. A marathon may lead to acute structural changes in the Achilles, including change in diameter and increased Doppler flow.Study designProspective cohort studyMethods41 Achilles tendons in 21 marathon runners were examined with grey-scale and colour Doppler ultrasound (US) before and immediately after the London Marathon, 2010. Six females and 15 males, mean age 40 years (±13) were included. 17 tendons were re-examined at 16 days (±1.6) postmarathon. Anteroposterior (AP) diameter (mm), grey-scale pathology (present, absent) and Doppler flow (present, absent) were measured.ResultsMean race time was 03:45 h (±33 min). US examination revealed 14 of 41 tendons (34%) had abnormalities before the marathon.After the marathon, mean tendon diameter decreased significantly in both normal and abnormal tendons (53 mm–47 mm, p=0.005). Tendon diameter returned to premarathon thickness after 16 days (±1.6 days). Doppler flow was present in seven of 41 tendons (17%) before the race. This did not significantly increase in direct response to the marathon (p=0.41). There was an association between abnormal tendons and faster marathon times (p=0.005).ConclusionsAbout 1/3 of the runners had structural abnormalities at baseline which did not increase immediately after the marathon. AP tendon diameter significantly decreased in normal and abnormal tendons immediately after the race. Tendon thickness appears to return to baseline at 2 weeks postmarathon.
Evaluation of an interprofessional multimedia musculoskeletal examination teaching resource: a qualitative study
Authors: Griffin C , Chung C , Tzortziou-Brown V , Morrissey D 
Published: January 2011

BackgroundInterprofessional education (IPE) has been used more frequently in the last thirty years to encourage collaborative teamwork within healthcare.ObjectivesThe aims of this study were primarily to assess the impact of multimedia instruction on musculoskeletal clinical examination (MCE) skill acquisition. Secondly, to evaluate students' perceptions of the value of IPE and multi disciplinary team (MDT) work.MethodA survey was administered to a purposively sampled group of postgraduate students, comprising medical practitioners and physiotherapists (n=26). The sample was diverse in age, speciality, and MDT and IPE experience. The intervention was four sports injury assessment DVDs made by expert clinicians modelling high level interprofessional team working, made specifically for use in the study. Postintervention semi-structured interviews, conducted with a sample from the survey group (n=10) until data saturation occurred, were audio-recorded and analysed by thematic content analysis.ResultsAn 85% survey response rate was obtained. 46% of the group described their competence in MCE as ‘developing skills’ and 50% described having ‘some experience’. Attitudes towards IPE and MDT work were highly positive; overriding beliefs were that they benefited practice by affording a range of learning opportunities. Interview analysis revealed five main themes: a real time approach with expert instruction; multiple perspectives; and diversity within the cohort; changing behaviour by improving MCE technique and enhancing interactive skills. Overriding beliefs were that observing and learning from different experts' skilful examination under real time conditions was perceived as largely beneficial across the whole group.ConclusionThis study provides evidence that interprofessional learning among postgraduate students can result in skill development – such as advanced assessments skills. Furthermore, the DVDs improved students' appreciation of IPE, healthcare teamwork, and awareness of other disciplines. The use of DVD learning tools to teach and assist with the delivery of MCE and IPE warrants further investigation.
Arterial stiffness before and after moderate intensity exercise in athletes and controls: a cross-sectional observational study
Authors: Dulai R , Ahmed M , Morrissey D , Twycross-Lewis R , Greenwald S 
Published: January 2011

BackgroundArterial stiffness is an independent predictor for cardiovascular disease and mortality. There has been no previous research comparing the acute effects of exercise on arterial stiffness in resistance and endurance athletes. This information would help to reveal how arterial function responds to exercise training.ObjectivesTo measure and compare arterial stiffness and hemodynamic variables in resistance athletes, endurance athletes and controls, before and after moderate intensity exercise.MethodsCentral and peripheral pulse wave velocity (PWV) was measured using Doppler ultrasound and calculated by the ‘foot to foot’ method before and after exercise. PWV was initially measured at rest for a 1 min period. Thereafter subjects cycled for 30 min at moderate intensity (60% of maximum heart rate, based on age). PWV was measured at postexercise intervals of 3, 15 and 30 min. Blood pressure and heart rate measurement preceded all PWV measurements.ResultsControls were significantly younger than both athletic groups (p<0.05). Groups did not significantly differ in resting PWV. There was no change in central/peripheral PWV after exercise in the resistance and control groups. Central PWV significantly increased post exercise in endurance athletes (mean (sd) resting PWV: 8.0 (2.0) m/s; 3 min postexercise: 10.5 (4.0) m/s; p=0.027, 95% CIs: 0.30 to 4.42) and recovered to resting values by 15 min. Systolic blood pressure increased significantly (p<0.05) in the endurance group from 136 (16) g at rest to 151 (13) 3 min after exercise.ConclusionsPWV in the endurance group significantly increased after exercise, possibly due to the concomitant rise in blood pressure. However, PWV did not change in response to exercise in the resistance or control groups. Lack of significant differences between the groups may be explained by problems with ultrasound measurement and a small sample size in the resistance group.
The effect of eccentric and concentric loading speed on the normal achilles tendon: an in vivo biomechanical study
Authors: Sweeney E , Chaudhury S , Screen H , Woledge R , Bader D , Maffulli N , Morrissey D 
Published: January 2011

BackgroundTendinopathy is a common and disabling condition that can end an athlete's career. Eccentric loading has proven to be an effective treatment measure for tendinopathy. However, current evidence is unclear regarding the optimum speed for eccentric loading.ObjectivesTo compare the effects of two different speeds of eccentric and concentric loading on Achilles tendon force and muscle activation in healthy volunteers.MethodsNine healthy volunteers (4 male, 5 female, age range 19–24) performed eccentric and concentric heel raises/drops at two speeds, in a random order. Motion analysis, force plate and electromyography (EMG) data were collected in order to measure Achilles tendon force and muscle activation.ResultsThe effect of speed on Achilles tendon force was not significant (p=0.74) but the effect of contraction type was significant (p<0.05). There was a significant difference between eccentric and concentric loading on EMG output for gastrocnemius medialis, lateralis and soleus (p<0.001 for all) but there was no significant effect of speed (p=0.05, 0.32, 0.06 respectively). For tibialis anterior and fibularis longus there was a significant effect of speed on EMG (p<0.001 for both) but not of contraction type (p=0.10, 0.30 respectively).ConclusionThere is no effect of speed on Achilles tendon force and the effect of speed on EMG activity is only significant for tibialis anterior and fibularis longus, therefore mechanical challenges to the tendon that are speed dependent are not likely to be due to force magnitude. The differential effects on muscle training may be significant. Further studies in patients are warranted.
A prospective cohort study of vertical pressure on hands of sitting volleyball players using tekscan pressure mat
Authors: Zhang JM , Bader D , Twycross-Lewis R , Padhiar N 
Published: January 2011

IntroductionCurrent sports medicine knowledge of sitting volleyball injuries in the UK is poor. This prospective pilot study looks at vertical pressures exerted on the hands of sitting volleyball players in controlled movements and compares them to a prospective survey of blister incidences.MethodThe pilot study was conducted in Mile End Hospital, London. Using Tekscan F-mat 3150, the researcher recorded peak vertical pressure on volunteer sitting volleyball players. 12 months prospective survey collected demographic data and blister incidences on player volunteers.ResultsData from pressure readings generated a geographical model of typical peak pressures on the hand. The data from the prospective survey generated a geographical map of blister hotspots. The locations of peak vertical pressure correlated with blister hotspots on the hands. Pressure readings from the small volunteer group showed highest peak pressure reading over the proximal aspect of the palm-hypothenar eminence. Real time trajectory of the centre of force was between pisiform and scaphoid of the thenar hypothenar eminences in large portion of the real time trajectory path before transferring to the 2nd and 3rd fingers via the metacarpalphalangeal joints. The lack of recruitment numbers for the pressure readings reduced the accuracy of the data such that the results were more descriptive in nature.ConclusionIndication from this pilot study suggests that sitting volleyball hand movements can be assessed using gait analysis techniques with a pressure sensitive mat. Further research is recommended.