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Papillomavirus late gene expression is tightly linked to the differentiation state of the host cell. Levels of late mRNAs are only in part controlled by regulation of the late promoter, other posttranscriptional mechanisms exist that reduce the amount of late mRNA in undifferentiated cells. Previously we described a negative regulatory element (NRE) located upstream of the human papillomavirus type 16 late poly(A) site. We have delineated the NRE to a 79-nt region in which a G+U-rich region was the major determinant of NRE activity. UV-crosslinking assays identified a prominent nuclear protein of 65 kda as the only factor in close contact with the NRE, and a complex of at least five proteins, including the 65-kDa protein, was enriched on NRE-RNA. Binding of the 65-kDa protein was depleted by preincubation with poly(U) Sepharose in high salt, a property characteristic of the U2 small nuclear ribonucleo-protein auxiliary factor U2A[F.sup.65] and bacterially expressed U2A[F.sup.65] exhibited NRE binding. The 65-kDa protein bound to the G+U-rich NRE 3[prime] half which shows homology to the B2P2 sequence a known U2A[F.sup.65] binding site in the [Alpha]-tropomyosin gene, and the G+U-rich element can be replaced by B2P2 in the binding assay. Treatment of cells with phorbol 12-myristate 13-acetate reduced binding of the 65-kDa protein, induced NRE binding of a cytoplasmic protein, and relieved the NRE block on reporter gene expression.

Abstract Background Human papillomavirus (HPV) is well known as the major etiological agent for ano-genital cancer. In contrast to cervical cancer, anal cancer is uncommon, but is increasing steadily in the community over the last few decades. However, it has undergone an exponential rise in the men who have sex with men (MSM) and HIV + groups. HIV + MSM in particular, have anal cancer incidences about three times that of the highest worldwide reported cervical cancer incidences. Discussion There has therefore traditionally been a lack of data from studies focused on heterosexual men and non-HIV + women. There is also less evidence reporting on the putative precursor lesion to anal cancer (AIN – anal intraepithelial neoplasia), when compared to cervical cancer and CIN (cervical intraepithelial neoplasia). This review summarises the available biological and epidemiological evidence for HPV in the anal site and the pathogenesis of AIN and anal cancer amongst traditionally non-high risk groups. Summary There is strong evidence to conclude that high-grade AIN is a precursor to anal cancer, and some data on the progression of AIN to invasive cancer.

Abstract Background Human papillomaviruses (HPV) are causally associated with ano-genital and a subset of head and neck cancers. Rising incidence of HPV+ anal cancers and head and neck cancers have now been demonstrated in the developed world over the last decade. The majority of published data on HPV prevalence at the anal and oro-pharyngeal sites are from studies of higher-risk populations. There is a paucity of data on the prevalence of HPV at non-cervical sites in lower risk, non-HIV+ women and this study was designed to provide initial pilot data on a population of women recalled for colposcopy as part of the UK cervical screening programme. Methods 100 non-HIV+ women with abnormal cervical cytology, attending clinic for colposcopic examination were recruited. Swabs from the oro-pharyngeal, anal and cervical sites were taken and DNA extracted. HPV detection and genotyping were performed using a standardised, commercially available PCR-line blot assay, which is used to genotype 37 HPV subtypes known to infect the ano-genital and oro-pharyngeal areas. Strict sampling and laboratory precautions were taken to prevent cross-contamination. Results There was a very high prevalence of HPV infection at all three sites: 96.0%, 91.4% and 92.4% at the cervix, anus and oro-pharynx, respectively. Multiple HPV subtype infections were dominant at all 3 mucosal sites. At least one or more HR genotype was present at both the cervix/anus in 39/52 (75.0%) patients; both the cervix/oro-pharynx in 48/56 (85.7%) patients; and both the anus/oro-pharynx in 39/52 (75.0%) patients. HPV 16 infection was highly dominant across all mucosal sites, with over a 2-fold increase over the next most prevalent subtype (HPV 31). Conclusions Women with abnormal smears have widespread infection with high-risk HPV at the cervical, anal and oro-pharyngeal mucosal sites and may represent a higher risk population for HPV disease in the future.

Abstract HPV infection in the genital tract is common in young sexually active individuals, the majority of whom clear the infection without overt clinical disease. However most of those who develop benign lesions eventually mount an effective cell mediated immune (CMI) response and the lesions regress. Failure to develop effective CMI to clear or control infection results in persistent infection and, in the case of the oncogenic HPVs, an increased probability of progression to CIN3 and invasive carcinoma. The prolonged duration of infection associated with HPV seems to be associated with effective evasion of innate immunity thus delaying the activation of adaptive immunity. Natural infections in animals show that neutralising antibody to the virus coat protein L1 is protective suggesting that this would be an effective prophylactic vaccine strategy. The current prophylactic HPV VLP vaccines are delivered i.m. circumventing the intra-epithelial immune evasion strategies. These vaccines generate high levels of antibody and both serological and B cell memory as evidenced by persistence of antibody and robust recall responses. However there is no immune correlate - no antibody level that correlates with protection. Recent data on how HPV infects basal epithelial cells and how antibody can prevent this provides a mechanistic explanation for the effectiveness of HPV VLP vaccines.

Abstract Background Human papillomaviruses (HPV) are the aetiological agents of certain benign and malignant tumours of skin and mucosae; the most important of which is cervical cancer. Also, the incidence of ano-genital warts, HPV-anal cancer and oropharyngeal cancers are rising. To help ascertain a useful PCR detection protocol for oropharyngeal cancers, we directly compared three commonly used primer sets in detection of HPV from different clinical samples. Methods We compared PGMY09/11, MY09/11 and GP5+/6+ primers sets in PCRs of 34 clinically diagnosed samples of genital warts, cervical brushings (with associated histological diagnosis) and vulval biopsies. All negative samples were subsequently tested using the previously reported PGMY/GP PCR method and amplicons directly sequenced for confirmation and typing. An optimised PCR protocol was then compared to a line blot assay for detection of HPV in 15 oropharyngeal cancer samples. Results PGMY09/11 primers detected HPV presence in more cervical brushing (100%) and genital wart (92.9%) samples compared to MY09/11 (90% and 64.3%) and GP5+/6+ (80% and 64.3%) primer sets, respectively. From vulval biopsies, HPV detection rates were: MY09/11 (63.6%), GP5+/6+ (54.5%) and PGMY09/11 (54.5%). PGMY/GP nested PCR demonstrated that HPV was present, and direct sequencing confirmed genotypes. This nested PCR protocol showed detection of HPV in 10/15 (66.7%) of oropharyngeal cancer samples. Conclusions PGMY09/11 primers are the preferred primer set among these three for primary PCR screening with different clinical samples. MY09/11 and GP5+/6+ may be used (particularly for cervical samples) but demonstrate lower detection rates. A nested PCR approach (i.e. a PGMY-GP system) may be required to confirm negativity or to detect low levels of HPV, undetectable using current primary PCR methods, as demonstrated using oropharyngeal cancer samples.

To tackle pollinator declines, there is a major need to increase the quantity of flower‐rich habitats. Road verges offer one such opportunity but are exposed to diverse forms of pollution from roads and road traffic.We carried out a broad initial assessment to establish if and how pollution affects the quality of road verges as pollinator foraging environments. We assessed the spatial distribution of pollution, flowers and pollinators in road verges, then used field experiments to simulate and measure the impacts of four ubiquitous and little studied forms of road pollution (noise, turbulence, dust and metals) on pollinator densities and foraging behaviour.We found that pollinators in road verges were exposed to noise, turbulence, dust and metal pollution, which decreased with distance from the road edge but, with the exception of turbulence, extended more than 8 m into road verges.Pollinator densities were lower closer to the road edge—particularly within first 2 m (55% lower than at 7–9 m)—where pollution is greatest. This was despite a similar density and species richness of flowers.Simulated turbulence deterred pollinators by causing intermittent disturbance (reducing visit duration by up to 54%), and some pollinator taxa preferentially avoided concentrations of metals that were more frequently found in flowers within 2 m of roads (resulting in up to 75% fewer visits), while noise and dust had no apparent effect.Synthesis and applications. Pollinators in road verges are exposed to many forms of pollution, and we found impacts of roadside‐realistic levels of turbulence and metals on pollinator densities and foraging behaviour. Although the findings suggest that road verges are largely suitable for pollinator conservation, management enhancements should prioritise areas more than 2 m from the road edge, and verges along roads with relatively lower traffic densities. [ABSTRACT FROM AUTHOR]

Monitoring is an important component of pest species management in New Zealand. Chew cards are increasingly used for mammalian pest monitoring. They are effective for measuring the relative abundance of rats (Rattus spp.), but their effectiveness for measuring hedgehog (Erinaceus europaeus) relative abundance has not been tested. Camera traps are also increasingly used as a monitoring tool, but there has been little calibration with other methods. We investigated whether chew card indices and camera indices for hedgehogs and rats gave consistent monitoring results. We also explored the relationship between the relative abundance of rats and hedgehogs using these indices. Hedgehog and rat chew card indices both showed a positive relationship with the respective camera indices for each taxon. However, cameras had fewer detections than chew cards when relative abundance was low (particularly for rats). Interference by rats did not appear to affect detection of hedgehogs with chew cards. Although not a strongly supported result in our study, the relationship between rat and hedgehog relative abundances requires further study and is a reminder that single-species pest control may not produce desired biodiversity outcomes. [ABSTRACT FROM AUTHOR]

Abstract Background Human papilloma virus (HPV) load and physical status are considered useful parameters for clinical evaluation of cervical squamous cell neoplasia. However, the errors implicit in HPV gene quantification by PCR are not well documented. We have undertaken the first rigorous evaluation of the errors that can be expected when using SYBR green qPCR for quantification of HPV type 16 gene copy numbers. We assessed a modified method, in which external calibration curves were generated from a single construct containing HPV16 E2, HPV16 E6 and the host gene hydroxymethylbilane synthase in a 1:1:1 ratio. Results When testing dilutions of mixed HPV/host DNA in replicate runs, we observed errors in quantifying E2 and E6 amplicons of 5–40%, with greatest error at the lowest DNA template concentration (3 ng/μl). Errors in determining viral copy numbers per diploid genome were 13–53%. Nevertheless, in cervical keratinocyte cell lines we observed reasonable agreement between viral loads determined by qPCR and Southern blotting. The mean E2/E6 ratio in episome-only cells was 1.04, but with a range of 0.76–1.32. In three integrant-only lines the mean E2/E6 ratios were 0.20, 0.72 and 2.61 (values confirmed by gene-specific Southern blotting). When E2/E6 ratios in fourteen HPV16-positive cervical carcinomas were analysed, conclusions regarding viral physical state could only be made in three cases, where the E2/E6 ratio was ≤ 0.06. Conclusion Run-to-run variation in SYBR green qPCR produces unavoidable inaccuracies that should be allowed for when quantifying HPV gene copy number. While E6 copy numbers can be considered to provide a useable indication of viral loads, the E2/E6 ratio is of limited value. Previous studies may have overestimated the frequency of mixed episomal/integrant HPV infections.

Ants represent a highly diverse and ecologically important group of insects found in almost all terrestrial ecosystems. A subset of ant species have been widely transported around the globe and invade many natural ecosystems, often out-competing native counterparts and causing varying impacts on recipient ecosystems. Decisions to control non-native ant populations require an understanding of their interactions and related impacts on native communities. We employed stable isotope analysis and metabarcoding techniques to identify potential dietary niche overlap and identify gut contents of 10 ant species found in natural ecosystems in Aotearoa New Zealand. Additionally, we looked at co-occurrence to identify potential competitive interactions among native and non-native ant species. Ants fed mainly across two trophic levels, with high dietary overlap. Relative to other ant species sampled, two non-native ant species, Linepithema humile and Technomyrmex jocosus , were found to feed at the lowest trophic level. The largest isotopic niche overlap was observed between the native Monomorium antarcticum and the invasive Ochetellus glaber , with analyses revealing a negative co-occurrence pattern. Sequence data of ant gut content identified 51 molecular operational taxonomic units, representing 22 orders and 34 families, and primarily consisting of arthropod DNA. Although we generally found high dietary overlap among species, negative occurrence between a dominant, non-native species and a ubiquitous native species indicates that species-specific interactions could be negatively impacting native ecosystems. Our research progresses and informs the currently limited knowledge around establishing protocols for metabarcoding to investigate ant diet and interactions between native and non-native ant species. [ABSTRACT FROM AUTHOR]

Interaction networks among native and invasive species in a community can inform both invasion impacts and applied management of invasive species. The intensity of aggressive interactions may be related to the overlap in species' ecological niche and functional traits, especially in cavity‐breeding species, that often compete for limited nesting sites. Australia is home to over 100 native and introduced cavity‐nesting species, including several invasive species that are widespread globally, such as the common myna Acridotheres tristis. Here, we aimed to test the extent to which shared functional traits inform the intensity of aggression between cavity‐nesting birds.We quantified the outcomes of aggressive interactions between birds in large hollow‐bearing trees in SE Queensland, Australia. We examined whether more similarly sized birds interacted more frequently, whether larger species won aggressive interactions more often, and whether cavity‐breeding species with similar preferences for nesting sites (breeding‐niche space) interacted more frequently.We recorded a total of 410 aggressive interactions and 48 interacting bird species around tree hollows, including 20 cavity‐nesting bird species. These interactions were dominated by the invasive common myna, the native noisy miner (a non‐cavity‐breeder) and the native rainbow lorikeet Trichoglossus moluccanus, but the common myna won the largest total number of interspecific interactions. On average, larger birds won aggressive interactions more frequently, yet there were some important exceptions to this finding; the common myna (113 ± 30 g) won 26 of the 29 interactions against the larger native rainbow lorikeet (126 ± 44 g). Importantly, species with more similar nest‐site preferences were observed aggressively interacting more frequently.Synthesis and applications. The impact of the invasive common myna was higher‐site preferences. Control efforts for the myna should focus on birds that nest in natural tree hollows. An analysis of shared traits by managers could be used to help identify how many local species would benefit from common myna control in a given area and test if further behavioural studies of common myna are warranted. [ABSTRACT FROM AUTHOR]

Residential green spaces in cities can make a significant contribution to urban conservation. To engage urban residents in conservation, we need to understand what influences participation. We interviewed leaders of community conservation groups and surveyed members of the public in Auckland, New Zealand using an anonymous questionnaire. We investigated whether environmental attitudes differ between those who do and do not participate in conservation actions (volunteering in a community conservation group and/or controlling pest mammals), and the motivations and barriers to participating in conservation actions. We found that conservation leaders often founded their conservation groups with a biodiversity motivation, whereas many of their group members subsequently joined and continued to participate for social reasons. Conservation group members were more likely to be in favor of pest control and had more positive environmental attitudes than non-participants. They found group work more motivating and productive than working alone. For people already participating in conservation (controlling pests, leading a group, or volunteering), the most common barrier to increasing participation was opportunity, most notably a lack of time. We found that people tended to control pest mammals for self-interested reasons, such as preventing damage to their homes (67%; n = 358), whilst biodiversity motivations (protecting native species) were secondary (53%; n = 283). For people not participating in pest control, the primary barrier was a lack of interest in participating (26%; n = 109). Although people were supportive of conservation, biodiversity motivations alone are unlikely to be a sufficient motivator for participation. Given the range of different motivations and barriers, targeted messaging (e.g., promoting social connections) could increase participation in urban conservation. [ABSTRACT FROM AUTHOR]