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Less than half of stool samples from people symptomatic with infectious intestinal disease (IID) will identify a causative organism. A secondary data analysis was undertaken to explore whether symptomology alone could be used to make inferences about causative organisms. Data were utilised from the Second Study of Infectious Intestinal Disease in the Community. A total of 844 cases were analysed. Few symptoms differentiated individual pathogens, but grouping pathogens together showed that viral IID was more likely when symptom onset was in winter (odds ratio (OR) 2.08, 95% confidence interval (CI) 1.16–3.75) or spring (OR 1.92, 95% CI 1.11–3.33), the patient was aged under 5 years (OR 3.63, 95% CI 2.24–6.03) and there was loss of appetite (OR 2.19, 95% CI 1.29–3.72). The odds of bacterial IID were higher with diarrhoea in the absence of vomiting (OR 3.54, 95% CI 2.37–5.32), diarrhoea which persisted for >3 days (OR 2.69, 95% CI 1.82–3.99), bloody diarrhoea (OR 4.17, 95% CI 1.63–11.83) and fever (OR 1.67, 95% CI 1.11–2.53). Symptom profiles could be of value to help guide clinicians and public health professionals in the management of IID, in the absence of microbiological confirmation.
Gut microbiota have been shown to play a critical role in the maintenance of host health. Probiotics, which regulate gut microbiota balance, could serve as an effective alternative to antibiotic growth promoters. Since changes in the gastrointestinal tract, caused by a variety of different strains, groups and amounts of microorganisms, may be reflected in its histological structure, the aim of the present study was to examine the effects of rising doses of a mixed probiotic preparation on the structure and development of the small intestine of female turkeys. Eighty, three-day-old, healthy, female turkeys (Big-6 breed) were used in the current (16-week) study. The turkeys were randomly allocated to four weight-matched (59.70 ± 0.83 g) groups (n = 20), according to probiotic treatment dose (0, 107 cfu•g−1, 108 cfu•g−1 or 109 cfu•g−1, in 500 g•1000 kg−1) (cfu – a colony-forming unit). Three, non-genetically modified strains of probiotic cultures obtained from poultry, four bacterial and one yeast culture, were used. Histomorphometric analysis of the structure of the small intestinal wall of the duodenum and jejunum was performed. All probiotic doses used in the current study exerted a beneficial effect on the histological structure of the small intestine; however, the observed effect was dose and region dependent. Significant increases in villi height, crypt depth, villi and crypt width, mucosa thickness, epithelial height, enterocyte number, absorption surface and intestinal ganglia geometric indices were observed, specifically in the duodenum of birds receiving an intermediate dose of probiotic (108 cfu•g−1). The probiotic doses used in the current study differed significantly in their effect on the small intestine (P < 0.01), with the intermediate dose (108 cfu•g−1) significantly improving 58% of the parameters assessed, compared to the control. The duodenum was more susceptible to the favourable effects of the probiotic than the jejunum (56% v. 31% improvement in the parameters assessed) (P < 0.01). The weakest favourable effect was observed in the group that received the highest dose of probiotic.
Invasive rodents detrimentally affect native bird species on many islands worldwide, and rodent eradication is a useful tool to safeguard endemic and threatened species. However, especially on tropical islands, rodent eradications can fail for various reasons, and it is unclear whether the temporary reduction of a rodent population during an unsuccessful eradication operation has beneficial effects on native birds. Here we examine the response of four endemic land bird species on subtropical Henderson Island in the Pitcairn Island Group, South Pacific Ocean, following an unsuccessful rodent eradication in 2011. We conducted point counts at 25 sampling locations in 14 survey periods between 2011 and 2015, and modelled the abundance trends of all species using binomial mixture models accounting for observer and environmental variation in detection probability. Henderson Reed Warbler Acrocephalus taiti more than doubled in abundance (2015 population estimate: 7,194-28,776), and Henderson Fruit Dove Ptilinopus insularis increased slightly between 2011 and 2015 (2015 population estimate: 4,476–10,072), while we detected no change in abundance of the Henderson Lorikeet Vini stepheni (2015 population estimate: 554–3014). Henderson Crake Zapornia atra increased to pre-eradication levels following anticipated mortality during the operation (2015 population estimate: 4,960–20,783). A temporary reduction of rat predation pressure and rat competition for fruit may have benefitted the reed warbler and the fruit dove, respectively. However, a long drought may have naturally suppressed bird populations prior to the rat eradication operation in 2011, potentially confounding the effects of temporary rat reduction and natural recovery. We therefore cannot unequivocally ascribe the population recovery to the temporary reduction of the rat population. We encourage robust monitoring of island biodiversity both before and after any management operation to better understand responses of endemic species to failed or successful operations.
Increased anthelmintic resistance worldwide has lead many to investigate alternative methods of parasite control (Donaldson et al. 1998). In sheep it is believed that the larval contamination of the pasture is derived mainly from the mature breeding ewe due to the periparturient relaxation of immunity (PPRI). Donaldson et al. (1998) reported that increasing the metabolisable protein (MP) supply of the ewe in late pregnancy may moderate the PPRI. Previous studies investigating the effect of MP supply to dairy ewes on faecal nematode egg output have, however, not shown significant differences (Partington et al. 2003). This study investigates the effects of both MP supply and the effect of milking on the PPRI and worm burden.
With increasing incidence in anthelmintic drench resistance, it is appropriate that more sustainable approaches to controlling nematode infections in livestock should be investigated. It is believed that larval contamination of pasture originates from the mature breeding ewe during the periparturient breakdown of immunity. Donaldson et al. (1998) reported that increasing the metabolisable protein (MP) supply of the ewe in late pregnancy may moderate the periparturient relaxation of immunity. The most pronounced results to date are those involving the supplementation of diets with fishmeal, believed to be related to the ‘protected’ protein content of the ration. Fishmeal increases both MP and polyunsaturated fatty acid content of the diet but as yet it is unclear which of these components of the diet may affect immunity to parasites. This study investigated the role of MP supply in maintaining immunity to parasitic infection in pedigree Friesland dairy ewes.
Imaging biomarkers for Alzheimer's disease include medial temporal lobe
atrophy (MTLA) depicted on computed tomography (CT) or magnetic resonance
imaging (MRI) and patterns of reduced metabolism on fluorodeoxyglucose
positron emission tomography (FDG-PET).
To investigate whether MTLA on head CT predicts the diagnostic usefulness
of an additional FDG-PET scan.
Participants had a clinical diagnosis of Alzheimer's disease
(n = 37) or dementia with Lewy bodies (DLB;
n = 30) or were similarly aged controls
(n = 30). We visually rated MTLA on coronally
reconstructed CT scans and, separately and blind to CT ratings, abnormal
appearances on FDG-PET scans.
Using a pre-defined cut-off of MTLA ⩾5 on the Scheltens (0–8) scale, 0/30
controls, 6/30 DLB and 23/30 Alzheimer's disease had marked MTLA. FDG-PET
performed well for diagnosing Alzheimer's disease v. DLB
in the low-MTLA group (sensitivity/specificity of 71%/79%), but in the
high-MTLA group diagnostic performance of FDG-PET was not better than
In the presence of a high degree of MTLA, the most likely diagnosis is
Alzheimer's disease, and an FDG-PET scan will probably not provide
significant diagnostic information. However, in cases without MTLA, if
the diagnosis is unclear, an FDG-PET scan may provide additional
clinically useful diagnostic information.
Blood culture contamination (BCC) has been associated with unnecessary antibiotic use, additional laboratory tests and increased length of hospital stay thus incurring significant extra hospital costs. We set out to assess the impact of a staff educational intervention programme on decreasing intensive care unit (ICU) BCC rates to <3% (American Society for Microbiology standard). BCC rates during the pre-intervention period (January 2006–May 2011) were compared with the intervention period (June 2011–December 2012) using run chart and regression analysis. Monthly ICU BCC rates during the intervention period were reduced to a mean of 3·7%, compared to 9·5% during the baseline period (P < 0·001) with an estimated potential annual cost savings of about £250 100. The approach used was simple in design, flexible in delivery and efficient in outcomes, and may encourage its translation into clinical practice in different healthcare settings.
Daily methane production and feed intake were measured on 160 adult ewes, which were the progeny of 20 sires and 3 sire types (Merino, dual-purpose and terminal) from a genetically diverse flock. All animals were housed in individual pens and fed a 50/50 mix of chaffed lucerne and oaten hays at 20 g/kg liveweight (LW), with feed refusals measured for at least 10 days before the first of three 22-h measurements in respiration chambers (RC). Feed was withdrawn at 1600 h on the day before each RC test to encourage the ewes to eat the entire ration provided for them in the RC. After the first 1-day RC test, the sheep were returned to their pens for a day, then given a second 1-day RC test, followed by another day in their pens, then a third RC test. After all animals had been tested, they were ranked according to methane emissions adjusted for feed intake in the RC and on the previous day, enabling 10 low and 10 high methane animals to be chosen for repeat measurement. No variation between sires nor consistent effects of LW on feed eaten (%FE, expressed as per cent of feed offered) was evident in the 10 days before the first RC measurement. However, significant differences between sires (equivalent to an estimated heritability of 41%) were identified for %FE during the 2nd and 3rd days of RC testing (2 and 4 days after the initial RC test). The analysis of all data showed that methane emissions in the RC were related to feed intake on the day of testing and the two previous days (all P<0.0005). Before correcting for feed intake on previous days, there was some variation between sires in methane yield, equivalent to an estimated heritability of 9%. Correction for feed intake on the 2 previous days halved the residual variation, allowing other effects to be detected, including effects of LW, twins reared as singles, test batch, RC and test-day effects, but estimated sire variation fell to zero. In order to avoid potential biases, statistical models of methane emissions in the RC need to consider potential confounding factors, such as those identified as significant in this study.
Deaths in England attributable to pandemic (H1N1) 2009 deaths were investigated through a mandatory reporting system. The pandemic came in two waves. The second caused greater population mortality than the first (5·4 vs. 1·6 deaths per million, P<0·001). Mortality was particularly high in those with chronic neurological disease, chronic heart disease and immune suppression (450, 100, and 94 deaths per million, respectively); significantly higher than in those with chronic respiratory disease (39 per million) and those with no risk factors (2·4 per million). Greater mortality in the second wave has been observed in all previous influenza pandemics. This time, the explanation appears to be behavioural. This emphasizes the importance of maintaining public and clinical awareness of risks associated with pandemic influenza beyond the initial high-profile period.
Corrosion of artifacts from atmospheric trace gases occur continuously. A new polymeric system which provides atmospheric trace gas corrosion protection has been developed. These polymers are called Reactive Polymers. The polymers consist of a blend of polymer resin (eg. polyethylene, polypropylene, ABS, PVC) with stable solid-state additives. These polymers can be formed into bags, tubing, sheets, bubble-pack, trays, etc. Corrosion protection is provided for artifacts from ancient periods, such as chinese mirrors, and the Freer Chinese Bronzes, to fine silver items from Colonial times in the USA. This protection from corrosion or tarnish by atmospheric H2S, COS, and HCl is provided for extended periods of time.
As part of an effort to determine the feasibility of carbothermic reduction of alumina in plasmas, spatial distributions of temperature, velocity and species in the plume of an argon radio-frequency plasma with alumina and carbon additions were estimated using a two dimensional theoretical model of the flow field and a thermochemical model based on equilibrium conditions. Experimentally determined boundary conditions were input to the models. Using a 30 kW inductively coupled plasma, experimental measurements were made to allow comparison with predictions. A practical process for carbothermic reduction will require prevention of back reactions, either by separation of the aluminum species or by some kind of quenching of the process. The significance of the experimental results and comparisons with predictions are discussed.
Uncertainties exist regarding the population risks of hospitalization due to pandemic influenza A(H1N1). Understanding these risks is important for patients, clinicians and policy makers. This study aimed to clarify these uncertainties. A national surveillance system was established for patients hospitalized with laboratory-confirmed pandemic influenza A(H1N1) in England. Information was captured on demographics, pre-existing conditions, treatment and outcomes. The relative risks of hospitalization associated with pre-existing conditions were estimated by combining the captured data with population prevalence estimates. A total of 2416 hospitalizations were reported up to 6 January 2010. Within the population, 4·7 people/100 000 were hospitalized with pandemic influenza A(H1N1). The estimated hospitalization rate of cases showed a U-shaped distribution with age. Chronic kidney disease, chronic neurological disease, chronic respiratory disease and immunosuppression were each associated with a 10- to 20-fold increased risk of hospitalization. Patients who received antiviral medication within 48 h of symptom onset were less likely to be admitted to critical care than those who received them after this time (adjusted odds ratio 0·64, 95% confidence interval 0·44–0·94, P=0·024). In England the risk of hospitalization with pandemic influenza A(H1N1) has been concentrated in the young and those with pre-existing conditions. By quantifying these risks, this study will prove useful in planning for the next winter in the northern and southern hemispheres, and for future pandemics.
The time-dependent motion of water waves with a parametrically defined free surface is mapped to a fixed time-independent rectangle by an arbitrary transformation. The emphasis is on the general properties of transformations. Special cases are algebraic transformations based on transfinite interpolation, conformal mappings, and transformations generated by nonlinear elliptic partial differential equations. The aim is to study the effect of transformation on variational principles for water waves such as Luke’s Lagrangian formulation, Zakharov’s Hamiltonian formulation, and the Benjamin–Olver Hamiltonian formulation. Several novel features are exposed using this approach: a conservation law for the Jacobian, an explicit form for surface re-parameterization, inner versus outer variations and their role in the generation of hidden conservation laws of the Laplacian. Also some of the differential geometry of water waves becomes explicit. The paper is restricted to the case of planar motion, with a preliminary discussion of the extension to three-dimensional water waves.
Existing empirical research investigating the size of the equity premium has largely consisted of a series of innovations around a common theme: producing a better estimate of the equity premium by using better data or a better estimation technique. The equity premium estimate that emerges from most of this work matches one moment of the data alone: the mean difference between an estimate of the return to holding equity and a risk-free rate. We instead match multiple moments of U.S. market data, exploiting the joint distribution of the dividend yield, return volatility, and realized excess returns, and find that the equity premium lies within 50 basis points of 3.5%, a range much narrower than was achieved in previous studies. Additionally, statistical tests based on the joint distribution of these moments reveal that only those models of the conditional equity premium that embed time variation, breaks, and/or trends are supported by the data. In order to develop the joint distribution of the dividend yield, return volatility, and excess returns, we need a model of price and return fundamentals. We document that even recently developed analytically tractable models that permit autocorrelated dividend growth rates and discount rates impose restrictions that are rejected by the data. We therefore turn to a wider range of models, requiring numerical solution methods and parameter estimation by the simulated method of moments.
Streptococcus pneumoniae is a common cause of community-acquired pneumonia (CAP) but existing diagnostic tools have limited sensitivity and specificity. We enrolled adults undergoing chest radiography at three Indian Health Service clinics in the Southwestern United States and collected acute and convalescent serum for measurement of PsaA and PspA titres and urine for pneumococcal antigen detection. Blood and sputum cultures were obtained at the discretion of treating physicians. We compared findings in clinical and radiographic CAP patients to those in controls without CAP. Urine antigen testing showed the largest differential between CAP patients and controls (clinical CAP 13%, radiographic CAP 17%, control groups 2%). Serological results were mixed, with significant differences between CAP patients and controls for some, but not all changes in titre. Based on urine antigen and blood culture results, we estimated that 11% of clinical and 15% of radiographic CAP cases were due to pneumococcus in this population.
Echovirus type 11 (echo 11) has been isolated at the virus laboratory of Fairfield Hospital, Melbourne, Australia, in 20 of the 28 years since the laboratory was established. During this time two major epidemics have occurred; the first, in 1971–2 involved 90 patients with aseptic meningitis or respiratory illness. The second began in June 1979 and lasted for 11 months, during which echo 11 was isolated from 174 patients admitted to Fairfield Hospital, other Victorian and Tasmanian hospitals and a children's reception centre. The patients' illnesses included viral meningitis (66%), fever (10%), respiratory infections (7%) and gastroenteritis (2%). One baby died.
Echo 11 was recovered from nasopharyngeal swabs or aspirates, cerebrospinal fluid and faecal specimens and was isolated most frequently in the Borrie cell line. Isolates were readily identified by immune electron microscopy and/or neutralization tests.
Few population-based studies have investigated the epidemiology of adult community-acquired pneumonia (CAP). We aimed to determine the incidence of CAP in a population at high-risk for pneumococcal disease and to evaluate a standardized method for interpreting chest radiographs adapted from the World Health Organization paediatric chest radiograph interpretation guidelines. We reviewed radiology records at the two healthcare facilities serving the White Mountain Apache tribe to identify possible pneumonia cases ⩾40 years of age. We categorized patients with clinical criteria and a physician diagnosis of pneumonia as clinical CAP and those with clinical criteria and an acute infiltrate as radiographic CAP. We identified 100 (27/1000 person-years) and 60 (16/1000 person-years) episodes of clinical and radiographic CAP, respectively. The incidence of CAP increased with age. Both radiographic and clinical CAP were serious illnesses with more than half of patients hospitalized. Our case definitions and methods may be useful for comparing data across studies and conducting vaccine trials.
The bacteriological investigation of an outbreak of Legionnaires' disease in Glasgow Royal Infirmary affecting 16 patients is described. Most of the patients had been treated in high-dependency areas on two floors of the hospital supplied by the same two air-conditioned ventilation systems. The source of infection was traced to contamination of a cooling tower from which a plume of spray discharged into the intake vents of the two ventilation systems. Rubber grommets within the cooling tower probably provided a nidus of infection there. The control and management of the outbreak are discussed: a policy of frankness about the course and progress of the investigations was adopted and helped to allay anxiety on the part of both staff and media.