Stereocontrolled enantioselective total synthesis of the [2+2] quadrigemine alkaloids

Abstract A unified strategy for enantioselective total synthesis of all stereoisomers of the [2+2] family of quadrigemine alkaloids is reported. In this approach, two enantioselective intramolecular Heck reactions are carried out at the same time on precursors fashioned in four steps from either meso- or (+)-chimonanthine to form the two critical quaternary carbons of the peripheral cyclotryptamine rings of these products. Useful levels of catalyst control are realized in either desymmetrizing a meso precursor or controlling diastereoselectivity in elaborating C2-symmetric intermediates. None of the synthetic quadrigemines are identical with alkaloids isolated previously and referred to as quadrigemines A and E. In addition, we report improvements in our previous total syntheses of (+)- or (-)-quadrigemine C that shortened the synthetic sequence to 10 steps and provided these products in 2.2% overall yield from tryptamine

A Gamma-Herpesvirus Glycoprotein Complex Manipulates Actin to Promote Viral Spread

Viruses lack self-propulsion. To move in multi-cellular hosts they must therefore manipulate infected cells. Herpesviruses provide an archetype for many aspects of host manipulation, but only for alpha-herpesviruses in is there much information about they move. Other herpesviruses are not necessarily the same. Here we show that Murine gamma-herpesvirus-68 (MHV-68) induces the outgrowth of long, branched plasma membrane fronds to create an intercellular network for virion traffic. The fronds were actin-based and RhoA-dependent. Time-lapse imaging showed that the infected cell surface became highly motile and that virions moved on the fronds. This plasma membrane remodelling was driven by the cytoplasmic tail of gp48, a MHV-68 glycoprotein previously implicated in intercellular viral spread. The MHV-68 ORF58 was also required, but its role was simply transporting gp48 to the plasma membrane, since a gp48 mutant exported without ORF58 did not require ORF58 to form membrane fronds either. Together, gp48/ORF58 were sufficient to induce fronds in transfected cells, as were the homologous BDLF2/BMRF2 of Epstein-Barr virus. Gp48/ORF58 therefore represents a conserved module by which gamma-herpesviruses rearrange cellular actin to increase intercellular contacts and thereby promote their spread

An Essential Role for the Proximal but Not the Distal Cytoplasmic Tail of Glycoprotein M in Murid Herpesvirus 4 Infection

Murid herpesvirus-4 (MuHV-4) provides a tractable model with which to define common, conserved features of gamma-herpesvirus biology. The multi-membrane spanning glycoprotein M (gM) is one of only 4 glycoproteins that are essential for MuHV-4 lytic replication. gM binds to gN and is thought to function mainly secondary envelopment and virion egress, for which several predicted trafficking motifs in its C-terminal cytoplasmic tail could be important. We tested the contribution of the gM cytoplasmic tail to MuHV-4 lytic replication by making recombinant viruses with varying C-terminal deletions. Removing an acidic cluster and a distal YXXΦ motif altered the capsid distribution somewhat in infected cells but had little effect on virus replication, either in vitro or in vivo. In contrast, removing a proximal YXXΦ motif as well completely prevented productive replication. gM was still expressed, but unlike its longer forms showed only limited colocalization with co-transfected gN, and in the context of whole virus appeared to support gN expression less well. We conclude that some elements of the gM cytoplasmic tail are dispensible for MuHV-4 replication, but the tail as a whole is not

Foot pain and foot health in an educated population of adults: results from the Glasgow Caledonian University Alumni Foot Health Survey

Abstract Background Foot pain is common amongst the general population and impacts negatively on physical function and quality of life. Associations between personal health characteristics, lifestyle/behaviour factors and foot pain have been studied; however, the role of wider determinants of health on foot pain have received relatively little attention. Objectives of this study are i) to describe foot pain and foot health characteristics in an educated population of adults; ii) to explore associations between moderate-to-severe foot pain and a variety of factors including gender, age, medical conditions/co-morbidity/multi-morbidity, key indicators of general health, foot pathologies, and social determinants of health; and iii) to evaluate associations between moderate-to-severe foot pain and foot function, foot health and health-related quality-of-life. Methods Between February and March 2018, Glasgow Caledonian University Alumni with a working email address were invited to participate in the cross-sectional electronic survey (anonymously) by email via the Glasgow Caledonian University Alumni Office. The survey was constructed using the REDCap secure web online survey application and sought information on presence/absence of moderate-to-severe foot pain, patient characteristics (age, body mass index, socioeconomic status, occupation class, comorbidities, and foot pathologies). Prevalence data were expressed as absolute frequencies and percentages. Multivariate logistic and linear regressions were undertaken to identify associations 1) between independent variables and moderate-to-severe foot pain, and 2) between moderate-to-severe foot pain and foot function, foot health and health-related quality of life. Results Of 50,228 invitations distributed, there were 7707 unique views and 593 valid completions (median age [inter-quartile range] 42 [31–52], 67.3% female) of the survey (7.7% response rate). The sample was comprised predominantly of white Scottish/British (89.4%) working age adults (95%), the majority of whom were overweight or obese (57.9%), and in either full-time or part-time employment (82.5%) as professionals (72.5%). Over two-thirds (68.5%) of the sample were classified in the highest 6 deciles (most affluent) of social deprivation. Moderate-to-severe foot pain affected 236/593 respondents (39.8%). High body mass index, presence of bunions, back pain, rheumatoid arthritis, hip pain and lower occupation class were included in the final multivariate model and all were significantly and independently associated with moderate-to-severe foot pain (p < 0.05), except for rheumatoid arthritis (p = 0.057). Moderate-to-severe foot pain was significantly and independently associated lower foot function, foot health and health-related quality of life scores following adjustment for age, gender and body mass index (p < 0.05). Conclusions Moderate-to-severe foot pain was highly prevalent in a university-educated population and was independently associated with female gender, high body mass index, bunions, back pain, hip pain and lower occupational class. Presence of moderate-to-severe foot pain was associated with worse scores for foot function, foot health and health-related quality-of-life. Education attainment does not appear to be protective against moderate-to-severe foot pain

Murid Herpesvirus-4 Exploits Dendritic Cells to Infect B Cells

Dendritic cells (DCs) play a central role in initiating immune responses. Some persistent viruses infect DCs and can disrupt their functions in vitro. However, these viruses remain strongly immunogenic in vivo. Thus what role DC infection plays in the pathogenesis of persistent infections is unclear. Here we show that a persistent, B cell-tropic gamma-herpesvirus, Murid Herpesvirus-4 (MuHV-4), infects DCs early after host entry, before it establishes a substantial infection of B cells. DC-specific virus marking by cre-lox recombination revealed that a significant fraction of the virus latent in B cells had passed through a DC, and a virus attenuated for replication in DCs was impaired in B cell colonization. In vitro MuHV-4 dramatically altered the DC cytoskeleton, suggesting that it manipulates DC migration and shape in order to spread. MuHV-4 therefore uses DCs to colonize B cells

Glycosaminoglycan Interactions in Murine Gammaherpesvirus-68 Infection

Glycosaminoglycans (GAGs) commonly participate in herpesvirus entry. They are thought to provide a reversible attachment to cells that promotes subsequent receptor binding. Murine gamma-herpesvirus-68 (MHV-68) infection of fibroblasts and epithelial cells is highly GAG-dependent. This is a function of the viral gp150, in that gp150-deficient mutants are much less GAG-dependent than wild-type. Here we show that the major MHV-68 GAG-binding protein is not gp150 but gp70, a product of ORF4. Surprisingly, ORF4-deficient MHV-68 showed normal cell binding and was more sensitive than wild-type to inhibition by soluble heparin rather than less. Thus, the most obvious viral GAG interaction made little direct contribution to infection. Indeed, a large fraction of the virion gp70 had its GAG-binding domain removed by post-translational cleavage. ORF4 may therefore act mainly to absorb soluble GAGs and prevent them from engaging gp150 prematurely. In contrast to gp70, gp150 bound poorly to GAGs, implying that it provides little in the way of adhesion. We hypothesize that it acts instead as a GAG-sensitive switch that selectively activates MHV-68 entry at cell surfaces

Multiple Functions for ORF75c in Murid Herpesvirus-4 Infection

All gamma-herpesviruses encode at least one homolog of the cellular enzyme formyl-glycineamide-phosphoribosyl-amidotransferase. Murid herpesvirus-4 (MuHV-4) encodes 3 (ORFs 75a, 75b and 75c), suggesting that at least some copies have acquired new functions. Here we show that the corresponding proteins are all present in virions and localize to infected cell nuclei. Despite these common features, ORFs 75a and 75b did not substitute functionally for a lack of ORF75c, as ORF75c virus knockouts were severely impaired for lytic replication in vitro and for host colonization in vivo. They showed 2 defects: incoming capsids failed to migrate to the nuclear margin following membrane fusion, and genomes that did reach the nucleus failed to initiate normal gene expression. The latter defect was associated with a failure of in-coming virions to disassemble PML bodies. The capsid transport deficit seemed to be functionally more important, since ORF75c− MuHV-4 infected both PML+ and PML− cells poorly. The original host enzyme has therefore evolved into a set of distinct and multi-functional viral tegument proteins. One important function is moving incoming capsids to the nuclear margin for viral genome delivery

Comparative analysis of miRNAs and their targets across four plant species

BACKGROUND: MicroRNA (miRNA) mediated regulation of gene expression has been recognized as a major posttranscriptional regulatory mechanism also in plants. We performed a comparative analysis of miRNAs and their respective gene targets across four plant species: Arabidopsis thaliana (Ath), Medicago truncatula(Mtr), Brassica napus (Bna), and Chlamydomonas reinhardtii (Cre). RESULTS: miRNAs were obtained from mirBase with 218 miRNAs for Ath, 375 for Mtr, 46 for Bna, and 73 for Cre, annotated for each species respectively. miRNA targets were obtained from available database annotations, bioinformatic predictions using RNAhybrid as well as predicted from an analysis of mRNA degradation products (degradome sequencing) aimed at identifying miRNA cleavage products. On average, and considering both experimental and bioinformatic predictions together, every miRNA was associated with about 46 unique gene transcripts with considerably variation across species. We observed a positive and linear correlation between the number miRNAs and the total number of transcripts across different plant species suggesting that the repertoire of miRNAs correlates with the size of the transcriptome of an organism. Conserved miRNA-target pairs were found to be associated with developmental processes and transcriptional regulation, while species-specific (in particular, Ath) pairs are involved in signal transduction and response to stress processes. Conserved miRNAs have more targets and higher expression values than non-conserved miRNAs. We found evidence for a conservation of not only the sequence of miRNAs, but their expression levels as well. CONCLUSIONS: Our results support the notion of a high birth and death rate of miRNAs and that miRNAs serve many species specific functions, while conserved miRNA are related mainly to developmental processes and transcriptional regulation with conservation operating at both the sequence and expression level

Chronic paroxysmal hemicrania in paediatric age: report of two cases

Chronic paroxysmal hemicrania (CPH) is a rare primary headache syndrome, which is classified along with hemicrania continua and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) as trigeminal autonomic cephalalgia (TACs). CPH is characterised by short-lasting (2–30 min), severe and multiple (more than 5/day) pain attacks. Headache is unilateral, and fronto-orbital-temporal pain is combined with cranial autonomic symptoms. According to the International Classification of Headache Disorders, 2nd edition, the attacks are absolutely responsive to indomethacin. CPH has been only rarely and incompletely described in the developmental age. Here, we describe two cases concerning a 7-year-old boy and a 11-year-old boy with short-lasting, recurrent headache combined with cranial autonomic features. Pain was described as excruciating, and was non-responsive to most traditional analgesic drugs. The clinical features of our children’s headache and the positive response to indomethacin led us to propose the diagnosis of CPH. Therefore, our children can be included amongst the very few cases of this trigeminal autonomic cephalgia described in the paediatric age