Prevalent low-grade dysplasia: the strongest predictor of malignant progression in Barrett's columnar-lined oesophagus

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The Use of Self-Expanding Plastic Stents in the Management of Oesophageal Leaks and Spontaneous Oesophageal Perforations

Leakage after oesophageal anastomosis or perforation remains a challenge for the surgeon. Traditional management has been operative repair or intensive conservative management. Both treatments are associated with prolonged hospitalisation and high morbidity and mortality rates. Self-expanding metallic stents have played an important role in the palliation of malignant oesophageal strictures and the treatment of tracheoesophageal fistulae. However, self-expanding metal stents in benign oesophageal disease are associated with complications such as bleeding, food bolus impaction, stent migration, and difficulty in retrieval. The Polyflex stent is the only commercially available self-expanding plastic stent which has been used in the management of malignant oesophageal strictures with good results. This review will consider the literature concerning the use of self-expanding plastic stents in the treatment of oesophageal anastomotic leakage and spontaneous perforations of the oesophagus

Postrelease survival, vertical and horizontal movements, and thermal habitats of five species of pelagic sharks in the central Pacific Ocean

From 2001 to 2006, 71 pop-up satellite archival tags (PSATs) were deployed on five species of pelagic shark (blue shark [Prionace glauca]; shortfin mako [Isurus oxyrinchus]; silky shark [Carcharhinus falciformis]; oceanic whitetip shark [C. longimanus]; and bigeye thresher [Alopias superciliosus]) in the central Pacific Ocean to determine species-specific movement patterns and survival rates after release from longline fishing gear. Only a single postrelease mortality could be unequivocally documented: a male blue shark which succumbed seven days after release. Meta-analysis of published reports and the current study (n=78 reporting PSATs) indicated that the summary effect of postrelease mortality for blue sharks was 15% (95% CI, 8.5–25.1%) and suggested that catch-and-release in longline fisheries can be a viable management tool to protect parental biomass in shark populations. Pelagic sharks displayed species-specific depth and temperature ranges, although with significant individual temporal and spatial variability in vertical movement patterns, which were also punctuated by stochastic events (e.g., El Niño-Southern Oscillation). Pelagic species can be separated into three broad groups based on daytime temperature preferences by using the unweighted pair-group method with arithmetic averaging clustering on a Kolmogorov-Smirnov Dmax distance matrix: 1) epipelagic species (silky and oceanic whitetip sharks), which spent >95% of their time at temperatures within 2°C of sea surface temperature; 2) mesopelagic-I species (blue sharks and shortfin makos, which spent 95% of their time at temperatures from 9.7° to 26.9°C and from 9.4° to 25.0°C, respectively; and 3) mesopelagic-II species (bigeye threshers), which spent 95% of their time at temperatures from 6.7° to 21.2°C. Distinct thermal niche partitioning based on body size and latitude was also evident within epipelagic species

Potentially inappropriate medication use: the Beers' Criteria used among older adults with depressive symptoms

INTRODUCTION: The ageing population means prescribing for chronic illnesses in older people is expected to rise. Comorbidities and compromised organ function may complicate prescribing and increase medication-related risks. Comorbid depression in older people is highly prevalent and complicates medication prescribing decisions. AIM: To determine the prevalence of potentially inappropriate medication use in a community-dwelling population of older adults with depressive symptoms. METHODS: The medications of 191 community-dwelling older people selected because of depressive symptoms for a randomised trial were reviewed and assessed using the modified version of the Beers' Criteria. The association between inappropriate medication use and various population characteristics was assessed using Chi-square statistics and logistic regression analyses. RESULTS: The mean age was 81 (±4.3) years and 59% were women. The median number of medications used was 6 (range 1-21 medications). The most commonly prescribed potentially inappropriate medications were amitriptyline, dextropropoxyphene, quinine and benzodiazepines. Almost half (49%) of the participants were prescribed at least one potentially inappropriate medication; 29% were considered to suffer significant depressive symptoms (Geriatric Depression Scale ≥5) and no differences were found in the number of inappropriate medications used between those with and without significant depressive symptoms (Chi-square 0.005 p=0.54). DISCUSSION: Potentially inappropriate medication use, as per the modified Beers' Criteria, is very common among community-dwelling older people with depressive symptoms. However, the utility of the Beers' Criteria is lessened by lack of clinical correlation. Ongoing research to examine outcomes related to apparent inappropriate medication use is needed

Successive use of shared space by badgers and cattle: implications for Mycobacterium bovis transmission

Managing infectious disease demands understanding pathogen transmission. In Britain, transmission of Mycobacterium bovis from badgers (Meles meles) to cattle hinders the control of bovine tuberculosis (TB), but the mechanism of such transmission is uncertain. As badgers and cattle seldom interact directly, transmission might occur in their shared environment through contact with contamination such as faeces, urine and saliva. We used concurrent GPS collar tracking of badgers and cattle at four sites in Cornwall, southwest Britain, to test whether each species used locations previously occupied by the other species, within the survival time of M. bovis bacteria. Although analyses of the same data set showed that badgers avoided cattle, we found no evidence that this avoidance persisted over time: neither GPS-collared badgers nor cattle avoided space which had been occupied by the other species in the preceding 36 h. Defining a contact event as an animal being located <5 m from space occupied by the other species within the previous 36 h, we estimated that a herd of 176 cattle (mean herd size in our study areas) would contact badgers at least 6.0 times during an average 24-h period. Similarly, we estimated that a social group of 3.5 badgers (mean group size in our study areas) would contact cattle at least 0.76 times during an average night. Such frequent successive use of the same shared space, within the survival time of M. bovis bacteria, could potentially facilitate M. bovis transmission via the environment

Use of farm buildings by wild badgers: implications for the transmission of bovine tuberculosis

Diseases transmitted from wildlife to livestock or people may be managed more effectively if it is known where transmission occurs. In Britain, farm buildings have been proposed as important sites of Mycobacterium bovis transmission between wild badgers (Meles meles) and cattle, contributing to the maintenance of bovine tuberculosis (TB). Farmers are therefore advised to exclude badgers from buildings. We used GPS-collars and remote cameras to characterise badgers’ use of farm buildings at four TB-affected sites in southwestern Britain. Across 54 GPS-collared badgers, 99.8% of locations fell ≥3m from farm buildings. Remote cameras deployed in feed stores recorded just 12 nights with badger visits among 3,134 store-nights of monitoring. GPS-collared badgers used space near farm buildings less than expected based on availability, significantly preferring land ≥100m from buildings. There was no positive association between badgers’ use of farm buildings and the infection status of either badgers or cattle. Six GPS-collared badgers which regularly visited farm buildings all tested negative for M. bovis. Overall, test-positive badgers spent less time close to farm buildings than did test-negative animals. Badger visits to farm buildings were more frequent where badger population densities were high. Our findings suggest that, while buildings may offer important opportunities for M. bovis transmission between badgers and cattle, building use by badgers is not a prerequisite for such transmission. Identifying ways to minimise infectious contact between badgers and cattle away from buildings is therefore a management priority

A new malaria vector in Africa: Predicting the expansion range of Anopheles stephensi and identifying the urban populations at risk

In 2012, an unusual outbreak of urban malaria was reported from Djibouti City in the Horn of Africa and increasingly severe outbreaks have been reported annually ever since. Subsequent investigations discovered the presence of an Asian mosquito species; Anopheles stephensi, a species known to thrive in urban environments. Since that first report, An. stephensi has been identified in Ethiopia and Sudan, and this worrying development has prompted the World Health Organization (WHO) to publish a vector alert calling for active mosquito surveillance in the region. Using an up-to-date database of published locational records for An. stephensi across its full range (Asia, Arabian Peninsula, Horn of Africa) and a set of spatial models that identify the environmental conditions that characterize a species’ preferred habitat, we provide evidence-based maps predicting the possible locations across Africa where An. stephensi could establish if allowed to spread unchecked. Unsurprisingly, due to this species’ close association with man-made habitats, our maps predict a high probability of presence within many urban cities across Africa where our estimates suggest that over 126 million people reside. Our results strongly support the WHO’s call for surveillance and targeted vector control and provide a basis for the prioritization of surveillance

Mines and bats: the impact of open-pit mining on bat activity

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordAreas used in open-pit mining often undergo sudden and extensive landscape changes, including habitat fragmentation. With mining activity predicted to expand, understanding the impacts of this habitat loss on wildlife is key to developing effective mitigation at new mine developments. Despite this, research into the impacts of open-pit mines in general, and on bat populations in particular, is largely lacking. Here, we investigated potential impacts of a recently re-established open-pit mine in southwest Britain on bat activity in the surrounding landscape, using remote monitoring techniques. Distance from the mine site boundary was found to be an important predictor of bat species richness and activity levels, with the effect on richness extending to approximately 900 m from the site and the effect on activity potentially extending beyond the sampling range (1,200 m). The effect of distance from the site boundary on species richness also varied with the proportion of woodland cover. It appears that habitat loss within the mine site boundary may have reduced bat movement because of barrier effects. The study highlights the need for further research into the impacts of mines on bats.Wolf Mineral