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Background: This multicentre randomised trial is examining the effect of single flexible sigmoidoscopy (FS) screening on colorectal cancer (CRC) incidence and mortality. Previous analyses of this and other trials have only reported follow-up after FS for a maximum of 12 years. The objective of this analysis was to examine the long-term effects of FS after 17 years of follow-up. Methods: Between 1994 and 1999, 170,432 eligible men and women, who had indicated on a previous questionnaire that they would probably attend for screening if invited, were randomised to an intervention group (offered FS screening) or a control group (not contacted) in a 1:2 ratio. Randomisation was performed centrally in blocks of 12, and stratified by trial centre, general practice and household type. The primary outcomes were incidence and mortality of CRC. Hazard ratios (HR) and 95% confidence intervals (CI) for CRC incidence and mortality were estimated for intention-to-treat and per-protocol analyses. The trial is registered, number ISRCTN28352761. Findings: This analysis included 170,034 people (57,098 in the intervention and 112,936 in the control group). During screening and a median of 17.1 years’ follow-up, CRC was diagnosed in 1,230 individuals in the intervention and 3,253 in the control group, and 353 vs. 996 respectively died from CRC. In intention-to-treat analyses, CRC incidence was reduced by 26% (HR 0.74, 95% CI 0.70-0.80) and CRC mortality by 30% (HR 0.70, 95% CI 0.62-0.79). In per-protocol analyses, adjusted for non-compliance, CRC incidence and mortality were 35% (HR 0.65, 95% CI 0.59-0.71) and 41% (HR 0.59, 95% CI 0.49-0.70) lower in attenders. Interpretation: A single FS continues to provide substantial protection from CRC diagnosis and death, with protection lasting at least 17 years.

T his article is the second summarising the main findings and conclusions of the review of the role(s) and responsibilities of infection prevention and control nurses (IPCN) commissioned by the Department of Health (England) in 2000. It describes the activities that form the core work of IPCN, discusses the strengths and constraints of the current role and makes suggestions for the future development of IPCN roles within the Health Protection Agency (HPA) and Primary Care Trusts (PCT).

Background: The prevalence and the origin of HIV-1 subtype B, the most prevalent circulating clade among the long-term residents in Europe, have been studied extensively. However the spatial diffusion of the epidemic from the perspective of the virus has not previously been traced. Results: In the current study we inferred the migration history of HIV-1 subtype B by way of a phylogeography of viral sequences sampled from 16 European countries and Israel. Migration events were inferred from viral phylogenies by character reconstruction using parsimony. With regard to the spatial dispersal of the HIV subtype B sequences across viral phylogenies, in most of the countries in Europe the epidemic was introduced by multiple sources and subsequently spread within local networks. Poland provides an exception where most of the infections were the result of a single point introduction. According to the significant migratory pathways, we show that there are considerable differences across Europe. Specifically, Greece, Portugal, Serbia and Spain, provide sources shedding HIV-1; Austria, Belgium and Luxembourg, on the other hand, are migratory targets, while for Denmark, Germany, Italy, Israel, Norway, the Netherlands, Sweden, Switzerland and the UK we inferred significant bidirectional migration. For Poland no significant migratory pathways were inferred. Conclusion: Subtype B phylogeographies provide a new insight about the geographical distribution of viral lineages, as well as the significant pathways of virus dispersal across Europe, suggesting that intervention strategies should also address tourists, travellers and migrants. © 2009 Paraskevis et al; licensee BioMed Central Ltd.

The genetic barrier, defined as the number of mutations required to overcome drug-selective pressure, is an important factor for the development of HIV drug resistance. Because of high variability between subtypes, particular HIV-1 subtypes could have different genetic barriers for drug resistance substitutions. This study compared the genetic barrier between subtypes using some 2000 HIV-1 sequences (9600 of non-B subtype) isolated from antiretroviral- naive patients in Europe. Methods: The genetic barrier was calculated as the sum of transitions (scored as 1) and/or transversions (2.5) required for evolution to any major drug resistance substitution. In addition, the number of minor protease substitutions was determined for every subtype. Results: Few dissimilarities were found. An increased genetic barrier was calculated for I82A (subtypes C and G), V108I (subtype G), V118I (subtype G), Q151M (subtypes D and F), L210W (subtypes C, F, G, and CRF02_AG), and P225H (subtype A) (P G 0.001 compared with subtype B). A decreased genetic barrier was found for I82T (subtypes C and G) and V106M (subtype C) (P G 0.001 vs subtype B). Conversely, minor protease substitutions differed extensively between subtypes. Conclusions: Based on the calculated genetic barrier, the rate of drug resistance development may be similar for different HIV-1 subtypes. Because of differences in minor protease substitutions, protease inhibitor resistance could be enhanced in particular subtypes once the relevant major substitutions are selected. Key Words: HIV, non-B subtypes, drug resistance, genetic barrier

Background: The genetic barrier, defined as the number of mutations required to overcome drug-selective pressure, is an important factor for the development of HIV drug resistance. Because of high variability between subtypes, particular HIV-1 subtypes could have different genetic barriers for drug resistance substitutions. This study compared the genetic barrier between subtypes using some 2000 HIV-1 sequences (> 600 of non-B subtype) isolated from antiretroviral-naive patients in Europe. Methods: The genetic barrier was calculated as the sum of transitions (scored as 1) and/or transversions (2.5) required for evolution to any major drug resistance substitution. In addition, the number of minor protease substitutions was determined for every subtype. Results: Few dissimilarities were found. An increased genetic barrier was calculated for 182A (subtypes C and G), V 1081 (subtype G), V 1181 (subtype G), Q 15 1 M (subtypes D and F), L210W (subtypes C, F, G, and CRF02_AG), and P225H (subtype A) (P < 0.001 compared with subtype B). A decreased genetic barrier was found for I82T (subtypes C and G) and V106M (subtype C) (P < 0.001 vs subtype B). Conversely, minor protease substitutions differed extensively between subtypes. Conclusions: Based on the calculated genetic barrier, the rate of drug resistance development may be similar for different HIV-1 subtypes. Because of differences in minor protease substitutions, protease inhibitor resistance could be enhanced in particular subtypes once the relevant major substitutions are selected.

Background. Infection with drug-resistant human immunodeficiency virus type 1 (HIV-1) can impair the response to combination therapy. Widespread transmission of drug-resistant variants has the disturbing potential of limiting future therapy options and affecting the efficacy of postexposure prophylaxis. Methods. We determined the baseline rate of drug resistance in 2208 therapy-naive patients recently and chronically infected with HIV-1 from 19 European countries during 1996-2002. Results. In Europe, 1 of 10 antiretroviral-naive patients carried viruses with >= 1 drug-resistance mutation. Recently infected patients harbored resistant variants more often than did chronically infected patients (13.5% vs. 8.7%; P = .006). Non-B viruses (30%) less frequently carried resistance mutations than did subtype B viruses (4.8% vs. 12.9%;). Baseline resistance increased over time in newly diagnosed cases of non-B infection: from P

Peptidoglycan-polysaccharide polymers derived from group A streptococcal cell walls (PG-PS) were opsonized with either purified C3 or normal human serum and were used as a probe to investigate the mobility of CR1 and CR3, the C3b and iC3b receptors, respectively, on human neutrophils. Incubation of monolayers or cell suspensions of neutrophils with PG-PS opsonized with C3b or serum resulted in capping of PG-PS, as detected by fluorescein-labeled antibody to PS. No binding of PG-PS to neutrophils was observed with heat-inactivated serum. By 30 min the cell walls were internalized and observed in one to three vacuoles. Capping was totally inhibited when PG-PS opsonized with C3b or serum was preincubated with Fab'-anti-C3b. Similar inhibition was observed when C3b-opsonized PG-PS was incubated with neutrophils that were preincubated with anti-CR1 or fluid-phase C3b; only partial inhibition of neutrophil capping was observed by using serum-opsonized PG-PS. Because anti-CR1 blocks only the C3b receptor, the cap formation observed with serum-opsonized PG-PS is probably due to CR3. These results suggest that both CR1 and CR3 on neutrophils cap after stimulation by group A streptococcal cell wall fragments.

Tissue proteolytic enzymes are currently believed to be critical to the pathogenesis of panacinar emphysema. Polymorphonuclear leukocytes (Polys) have several enzymes including elastase and cathepsin G in their azurophil granules. They have collagenase in their specific granules. We have found that this collagenase is doubly latent. It has the lysosomal type of latency that depends on the impermeability of the unit membrane that surrounds each specific granule. In addition it has a latency that is converted to activity by proteolytic enzymes. The cathepsin G of the azurophil granule is a potent activator of this latent collagenase once the collagenase is released from its membrane dependent latency. Thus latency of enzymes, the nature of the latency and accessibility of the latent enzymes to activating mechanisms must all be taken into account in any analysis of their contribution to pathogenesis of local lung disease. Equally important is that fact that polys are not a prominent cellular component of normal lung. Polys must be attracted to the lung by chemotactic peptides. These peptides must be released by the interaction of inflammatory stimuli, such as smoke particles, with complement components or they must be provided by other sources. The hypothesis that lung damage in panacinar emphysema is mediated by polys and their proteases is attractive and suggestive evidence supporting this is available. However, more evidence that takes into full account the cell biology of the proteases any poly turnover in the lung are needed to extend the hypothesis and to form a rational basis for therapeutic and prophylactic measures.ImagesFIGURE 1.FIGURE 2.FIGURE 3.FIGURE 4.FIGURE 6.FIGURE 7.FIGURE 8.FIGURE 9.

Serum-opsonized group A streptococcal cell walls, consisting of peptidoglycan-polysaccharide polymers (PG-APS), induced monolayers of human neutrophils, monocytes, and eosinophils to aggregate. When erythrocytes were present in the incubation medium, they also were associated with the leukocyte aggregates. By immunofluorescence staining, PG-APS was localized at the site of cell-to-cell contact. By scanning electron microscopy the cells appeared to adhere to one another by surface contact; filopodia often acted as connectors, particularly in leukocyte-erythrocyte interaction. Cellular binding of PG-APS and aggregation were dependent upon C3 fixation. No aggregation was observed when heat-inactivated serum was used as an opsonin. In contrast to peptidoglycan, an activator of the alternative complement pathway, the group-specific polysaccharide moiety of PG-APS induced no cellular aggregation. Rosette formation was observed in suspensions when neutrophils were incubated with erythrocytes coated with C3b-opsonized PG-APS. Cell monolayers bound serum-opsonized PG-APS, but aggregation was observed only when serum was present in the incubation medium. Similar results were obtained with C5-deficient serum. No aggregation was observed with heat-inactivated serum or bovine serum albumin. A heat-labile serum component(s) appears to be required to elicit leukocyte aggregation. It is suggested that C3 fixed to PG-APS acts as a bridge to link cells together in clusters as a result of common recognition of C3 by leukocyte and erythrocyte complement receptors.

Impaired sensorimotor synchronisation (SMS) to acoustic rhythm may be a marker of atypical language development. Here, Motion Capture was used to assess gross motor rhythmic movement at six timepoints between five- and 11-months-of-age. Infants were recorded drumming to acoustic stimuli of varying linguistic and temporal complexity: drumbeats, repeated syllables and nursery rhymes. Longitudinal analyses revealed that whilst infants could not yet reliably synchronise their movement to auditory rhythms, infant spontaneous motor tempo became faster with age, and by 11-months, a subset of infants were able to decelerate from their spontaneous motor tempo, to better accord with the incoming tempo. Further, infants became more regular drummers with age, with marked decreases in the variability of spontaneous motor tempo and variability in response to drumbeats. This latter effect was subdued in response to linguistic stimuli. The current work lays the foundation for using individual differences in SMS in infancy to predict later language outcomes.

Background : Information about patterns of HIV-1 drug resistance among treatment-exposed patients is crucial for the development of novel effective drugs. Currently no system exists that monitors patterns of resistance in patients failing therapy. Methods : The study included 1,988 HIV-1 sequences from patients experiencing therapy failure collected between 2000 and 2004 in 15 European countries. Genotypic resistance was interpreted using the ANRS algorithm. Phenotypic resistance was predicted using the Virco geno- to phenotype system. Results : 80.7% of the sequences included at least one drug-resistance mutation. Mutations were found for NRTIs (73.5%), NNRTIs (48.5%), and protease inhibitors (35.8%). Ninety percent of sequences with genotypic resistance harbored M184V, M41L, K103N, D67N, and/or T215Y. Among NRTIs, resistance was most frequently predicted for lamivudine. About half of all sequences had reduced susceptibility for NNRTIs. Resistance to most boosted protease inhibitors was found in < 25%. No sequence had resistance to all currently available drugs. Conclusion : Levels of resistance among patients with therapy failure were high. The patterns of resistance reflect resistance to drugs available for a longer time. Fully suppressive regimens can be designed even for the most mutated HIV because boosted protease inhibitors have remained active against most circulating viruses and new drug classes have become available.