Backyard chicken keeping in the Greater London Urban Area: welfare status, biosecurity and disease control issues.

1. The aim of the study was to collect baseline data on welfare, biosecurity and diseases of backyard chickens kept in the Greater London Urban Area (GLUA), United Kingdom (UK). 2. A total of 65 backyard chicken flock-keepers were recruited from May to July 2010 through adverts on websites, at City farms, veterinary practices and pet feed stores and surveyed by means of a questionnaire. A total of 30 responses were suitable for analysis. 3. Information on keepers' and flocks' characteristics, housing and husbandry practices and owners' knowledge of health problems in chickens and zoonotic diseases was collected. A welfare assessment protocol was developed and the flocks assessed accordingly. 4. Results showed that chickens were generally provided with living conditions that allowed them to perform their natural behaviours. 5. Most of the flock owners did not comply with the regulations of the Department for Environment, Food and Rural Affairs (Defra) on the feeding of catering waste. 6. Disease prevention measures such as vaccination and biosecurity, including limiting the access of human visitors, wild birds and rodents to the flocks were rare. 7. A lack of avian and zoonotic disease knowledge and awareness among the owners has implications for disease control and highlights the need for improved communication between owners, authorities and veterinarians.

Factors related to the prevalence of pathogenic Yersinia enterocolitica on pig farms.

A survey of 788 pigs from 120 farms was conducted to determine the within-farm prevalence of pathogenic Yersinia enterocolitica and a questionnaire of management conditions was mailed to the farms afterwards. A univariate statistical analysis with carriage and shedding as outcomes was conducted with random-effects logistic regression with farm as a clustering factor. Variables with a P value <0·15 were included into the respective multivariate random-effects logistic regression model. The use of municipal water was discovered to be a protective factor against carriage and faecal shedding of the pathogen. Organic production and buying feed from a certain feed manufacturer were also protective against total carriage. Tonsillar carriage, a different feed manufacturer, fasting pigs before transport to the slaughterhouse, higher-level farm health classification, and snout contacts between pigs were risk factors for faecal shedding. We concluded that differences in management can explain different prevalences of Y. enterocolitica between farms.

Assessment of occupational exposure to uranium by indirect methods needs information on natural background variations.

Urine monitoring is the preferred method to determine exposure to soluble compounds of uranium in workplaces. The interpretation of uranium contents in workers bioassay samples requires knowledge on uranium excretion and its dependence on intake by diet. Exceptionally high concentrations of natural uranium in private drinking water sources have been measured in the granite areas of Southern Finland. Consequently, high concentrations of natural uranium have been observed in the urine and hair samples of people using water from their own drilled wells. Natural uranium content in urine and hair samples of family members, who use uranium-rich household water, have been analyzed by using ICP-MS. The uranium concentrations both in urine and hair samples of the study subjects were significantly higher than the world-wide average values. In addition, gammaspectrometric methods have been tested for determining uranium in hair samples. This method can be used only for samples with highly elevated uranium concentrations.

Determination of 234U/238U ratio: comparison of multi-collector ICPMS and ICP-QMS for water, hair and nails samples, and comparison with alpha-spectrometry for water samples.

The (234)U/(238)U ratio in water, hair and nails samples was determined by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) and by alpha-spectrometry for the water samples only. A correlation of 0.99 was found between the two ICPMS methods and of 0.98 with alpha-spectrometry. The range of activity ratios was between 0.9 and 2.6 according to the MC-ICPMS measurements. The reproducibility of both ICPMS techniques was better than 4% for water samples containing 1 mug l(-1) of uranium and a (234)U/(238)U atom ratio of 54.9 x 10(-6). Sample preparation for the ICPMS consisted of dilution of water samples containing >10 microg l(-1) of uranium and measurement time was approximately 1 min, while alpha-spectrometry involved pre-concentration and separation of the uranium and counting times of 1,000 min.

Self-Assembly and Formation of Chromonic Liquid Crystals from the Dyes Quinaldine Red Acetate and Pyronin Y.

The aqueous self-assembly behavior of the dyes Quinaldine red acetate and Pyronin Y in a wide range of concentrations is reported here for the first time. (1)H NMR spectroscopy, polarized-light optical microscopy, and small and wide X-ray scattering were used to get insight into molecular interactions, phase boundaries and aggregate structure. Quinaldine red acetate and Pyronin Y self-organize into unimolecular stacks driven by attractive aromatic interactions. At high concentrations, spatial correlation among the molecular stacks gives rise to nematic liquid crystals in both systems. Quinaldine red acetate additionally produces a rare chromonic O phase built of columnar aggregates with anisotropic cross-section ordered in a rectangular lattice. The O phase changes into a columnar lamellar structure as a result of a temperature-induced phase transition. Results open the possibility of finding chromonic liquid crystals in other commercially available dyes with a similar molecular structure. This would eventually expand the availability of these unique soft materials and thus introduce new applications for marketed dyes.

Measurement of the 234U/238U ratio by MC-ICPMS in drinking water, hair, nails, and urine as an indicator of uranium exposure source.

The isotopic ratio (234)U/(238)U in drinking water and in hair, toenail, and urine samples from 45 individuals who consumed 0.2-2775 microg d(-1) of uranium in their drinking water was determined using a multi-collector inductively coupled plasma mass spectrometer (MC-ICPMS). The U/U atom ratio in the water samples varied from 51 x 10(-6) to 252 x 10(-6) whereas in secular equilibrium (i.e., unity activity ratio) the ratio is 54.9 x 10(-6). The correlation of the (234)U/(238)U ratio between hair and nail samples was 0.98, and between hair and nails and urine the ratio was 0.91 and 0.89, respectively. The correlation of the ratio between water and the hair or nails was 0.97 but only 0.72 for water and urine, possibly due to spectral interferences. These results conclusively demonstrated that the uranium found in the bioassays can be traced to the drinking water, thus providing a direct link to the source of exposure. Hair may serve as an excellent indicator of occupational or environmental exposure to uranium and provide information regarding its source. Bioassay of hair is attractive as it is an effective bio-concentrator, samples can be easily stored, the concentration reflects an integrated value, and, finally, the measurement of the (234)U/(238)U isotopic ratio in digested hair samples by MC-ICPMS is feasible and highly informative. Hair bioassay can also be used to assess exposure to depleted uranium long after the subjects have left the area suspected of contamination.

Urine, hair, and nails as indicators for ingestion of uranium in drinking water.

The concentration of uranium in urine, hair, and nails due to continuous exposure through ingestion of drinking water was studied. The study population consisted of 205 individuals living in 134 different households in southern Finland where drinking water is supplied from private drilled wells. The population was selected to include a broad range of uranium daily intake from drinking water (0.03-2,775 microg d). The uranium content in drinking water, urine (overnight collection), hair and nails was determined by ICPMS. Uranium in urine was corrected for the matrix effects by use of thallium as an internal standard and adjusted by creatinine normalization. Hair and toenail samples were rinsed to remove external contamination prior to acid digestion and analysis. The uranium content in all excretion pathways was correlated with the uranium intake, particularly at elevated levels (> or =10 microg d) where drinking water was the major source of exposure to uranium. The median of the individual uranium absorption factors for urine, hair, and toenails were fu=0.003, fh=0.003, and fn=4 x 10, respectively. The association between the different bioassays was examined. The absorption factor, f1, was calculated for the population with an intake above 10 microg d and was below 0.01 for 72% of the study persons (range 0.0002 to 0.070). No statistically significant difference in f1 values was found between women and men. However, the absorption factor was higher among younger (< 60 y) than older (> or =60 y) subjects and among people with a lower exposure (below 100 microg d) than among those that ingest over 100 microg d.

Nociceptive responses of trigeminal neurons in SII-7b cortex of awake monkeys.

A cluster of trigeminal nociceptive neurons was located in the lateral sulcus on the upper bank of the frontoparietal operculum in a region bordering between cortical areas SII and 7b. These neurons were isolated in cortical cell layers IV and V-VI. All nociceptive neurons responded exclusively to noxious mechanical stimulation of cutaneous receptive fields on the face/head or intraoral tissue. Sustained noxious mechanical stimulation elicited slowly adapting responses that accurately encoded the duration of the stimulation. Prolonged discharges following removal of noxious stimulation were not observed. These nociceptive specific neurons poorly encoded graded noxious stimuli. Trigeminal somatosensory neurons within and surrounding the SII-7b cluster were not topographically organized according to divisions of the trigeminal nerve, laterality of receptive fields, or division of face/head and intraoral receptive fields. The thalamocortical, corticocortical and indirect corticolimbic connectivities of SII and area 7b and the possible role of SII-7b nociceptive neurons in learning, memory and avoidance behaviors are discussed.

Mutans streptococci, oral hygiene, and caries in an adult Swedish population.

The objective of the present study was to describe the distribution of salivary mutans streptococci in a randomly selected adult population and to relate the distribution to the prevalence of caries. The aim was also to study the association between caries and different levels of oral hygiene (OH). The results were based on the assessment of caries, dental plaque, and concentration of salivary mutans streptococci in 914 subjects who represented 95% of an age- and gender-stratified population sample of 967 individuals, randomly selected from the total adult population living in Alvsborg County, Sweden. The results showed that the distribution of mutans streptococci among dentate adults not wearing any kind of removable denture(s) was similar to that previously reported from studies on Swedish schoolchildren, while a comparably higher proportion of subjects with high levels of mutans streptococci was found among the dentate individuals wearing some kind of removable denture(s). Even higher proportions were found among edentulous individuals with complete denture(s). There was a correlation between mutans streptococci concentration in saliva and caries. The subjects with lower concentrations showed a significantly lower mean number of decayed surfaces, compared with the individuals with higher concentrations of mutans streptococci in their saliva. The median OH standard was lower in the older age groups, and there was a higher ratio of decayed surfaces per remaining tooth in those age groups, in comparison with the younger groups. However, for individuals without mutans streptococci, no relation between OH standard and caries could be found and, regardless of OH standard, higher numbers of decayed surfaces were found with an increasing concentration of mutans streptococci in saliva.

A rapid method for monitoring of uranium and radium in drinking water.

A time-saving and fairly accurate method for monitoring U and 226Ra in drinking water has been devised, using low-background liquid scintillation spectrometry and pulse-shape analysis. The samples are prepared for counting by evaporating water in a liquid scintillation vial. The residue is dissolved in 1 ml of 0.5 N HCl, and a scintillation cocktail is added. Counting is carried out twice: a few days and a month after the sample preparation using the Quantulus, a liquid scintillation spectrometer equipped with a guard counter and pulse-shape analyser. The counter produces separate alpha and beta spectra which enable calculation of the approximate U and 226Ra contents. These correlate well with the results obtained by radiochemical methods. The measured spectra give valuable information on the nuclide content, e.g. increased U, 226Ra, 210Pb and 210Po activities, and on the 234U: 238U activity ratio in the water. This kind of information is very valuable in deciding on the necessity for time-consuming radiochemical analyses for radiation protection purposes or exploration for U ore deposits. In many cases the results from the Quantulus are sufficient to determine the U and 226Ra levels in drinking water. The lower limits of detection for U and 226Ra are 0.02 and 0.01 Bq/l, respectively, when the counting time is 180 min and the sample volume 38 ml.

Estimation of human exposure to natural radionuclides using in vivo skull measurements.

In a preliminary study, in vivo skull measurements and in vitro urine measurements of 210Pb and nulU have been performed to find out the individual, chronic exposure to waterborne natural radionuclides of a small group of Finnish people. For their domestic water, the studied individuals use water from drilled wells containing elevated concentrations of natural uranium and its daughter nuclides ((234,235,238)U, 222Rn, (226,228)Ra, 210Po, 210Pb). Enhanced 210Pb and 235U activities were observed in several people. A positive correlation is observed between the U concentration in urine (microg d(-1)) and the number of counts (cpm) in the gamma ray energy peaks originating from the decay of 235U and 234Th respectively. Calibration of the detector set-up and the determination of background sources are in progress.

Oral health status in an adult Swedish population. Prevalence of teeth, removable dentures and occlusal supporting zones.

The present study, which is part of a comprehensive cross-sectional epidemiologic survey on oral health among the adult population in a Swedish county, reports the results from the clinical assessment of remaining teeth, "occlusal supporting zones" (Eichner 1955), prevalence of edentulousness and removable dentures. The survey was carried out during 1983-1984. The adult population of 122,886 inhabitants was stratified according to age, sex and place of residence. From the different strata 0.75% (1.5% above 79 years) of the population was randomly selected to participate in the survey. Of the 967 selected individuals 920 (95.1%) attended full examination. The results showed a gradual reduction in the mean number of remaining teeth by age; somewhat faster after the age of 50 coincident with a significant increase in the prevalence of edentulousness. The prevalence of edentulousness and complete dentures was about twice as high among women as among men. In the dentate individuals the occlusal status was less favorable among men. This finding may explain the observed higher prevalence of removable partial dentures among the dentate men compared to the dentate women. An extrapolation between the results from the present study and results from previous studies in the Swedish population indicates that the oral health in the population below 50 years of age has improved during the last decade. This trend may predict that the observed improvement will follow the population, at present younger than 50 years, up through the ages.

Oral health status in an adult Swedish population. Prevalence of caries. A cross-sectional epidemiological study in the Northern Alvsborg county.

The aim of the present epidemiological study was to describe prevalence, distribution and type of caries in an adult Swedish population. After stratification with respect to age (20-29, 30-39,.....greater than 79 years of age), sex and location of residence (city, village, rural region), a random sample of 967 individuals was drawn (0.75% of the total adult population greater than 19 years). The results were based on radiographic and clinical examination of 919 individuals, of whom 750 were dentate (participation rate: 95%). The examinations were carried out from November 1983 to December 1984. The caries registrations distinguished between enamel caries and root caries, subdivided into manifest and initial caries. Despite lower number of remaining teeth in older ages, the mean number of surfaces with manifest caries (DS) was relatively even in all age groups (4.1-5.1 DS), except for the youngest age group ("20-29 years": mean 3.1 DS). When the number of decayed teeth (DT) were expressed as a percentage of remaining teeth, the ratio (%) was markedly higher in the older age groups than in the younger age groups. Initial caries was more frequent in the younger age groups. In the age groups above forty years the majority of the observed carious lesions involved root surfaces. In the oldest age group ("greater than 79 years of age"), 95% of the lesions were root caries. The mean number of filled surfaces (FS) was higher among women than men, while untreated caries (DS) showed a tendency of higher values for men. No significant differences in caries prevalence related to location of residence could be demonstrated.

Prevalence, outcome and risk factors for postoperative pyothorax in 232 dogs undergoing thoracic surgery.

OBJECTIVE: To determine the prevalence, outcome and risk factors for postoperative pyothorax in dogs undergoing thoracic surgery. METHODS: Case records were reviewed retrospectively to identify dogs with post thoracic surgery pyothorax, defined as septic neutrophilic inflammation within the pleural space based on cytology and/or a positive bacterial culture of pleural fluid. Those identified were reviewed for potential risk factors for postoperative pyothorax based on biological plausibility and previously published data. These potential risk factors were explored by multivariable logistic regression. RESULTS: Of 232 dogs undergoing thoracic surgery, 15 (6.5%) dogs developed pyothorax. Bacteria cultured included methicillin-resistant Staphylococcus aureus and multi-resistant Escherichia coli. Of these dogs, six died, four were euthanased and five were treated successfully. A diagnosis of idiopathic chylothorax [Odds Ratio (OR)=12.5, 95% Confidence Interval (CI)=2.7-58.5, P=0.001], preoperative intrathoracic biopsy (OR=14.3, 95% CI=1.7-118.7, P=0.014) and preoperative thoracocentesis (OR=11.2, 95% CI=1.6-78.2, P=0.015) were identified as independent risk factors for development of postoperative pyothorax. CLINICAL SIGNIFICANCE: Idiopathic chylothorax, intrathoracic biopsy and prior thoracocentesis are independent risk factors for postoperative pyothorax, which was associated with a 67% mortality rate.

A compartmental model of uranium in human hair for protracted ingestion of natural uranium in drinking water.

To predict uranium in human hair due to chronic exposure through drinking water, a compartment representing human hair was added into the uranium biokinetic model developed by the International Commission on Radiological Protection (ICRP). The hair compartmental model was used to predict uranium excretion in human hair as a bioassay indicator due to elevated uranium intakes. Two excretion pathways, one starting from the compartment of plasma and the other from the compartment of intermediate turnover soft tissue, are assumed to transfer uranium to the compartment of hair. The transfer rate was determined from reported uranium contents in urine and in hair, taking into account the hair growth rate of 0.1 g d(-1). The fractional absorption in the gastrointestinal tract of 0.6% was found to fit best to describe the measured uranium levels among the users of drilled wells in Finland. The ingestion dose coefficient for (238)U, which includes its progeny of (234)Th, (234m)Pa, and (234)Pa, was calculated equal to 1.3 x 10(-8) Sv Bq(-1) according to the hair compartmental model. This estimate is smaller than the value of 4.5 x 10(-8) Sv Bq(-1) published by ICRP for the members of the public. In this new model, excretion of uranium through urine is better represented when excretion to the hair compartment is accounted for and hair analysis can provide a means for assessing the internal body burden of uranium. The model is applicable for chronic exposure as well as for an acute exposure incident. In the latter case, the hair sample can be collected and analyzed even several days after the incident, whereas urinalysis requires sample collection shortly after the exposure. The model developed in this study applies to ingestion intakes of uranium.

Reliability of cyclin A assessment on tissue microarrays in breast cancer compared to conventional histological slides.

Cyclin A has in some studies been associated with poor breast cancer survival, although all studies have not confirmed this. Its prognostic significance in breast cancer needs evaluation in larger studies. Tissue microarray (TMA) technique allows a simultaneous analysis of large amount of tumours on a single microscopic slide. This makes a rapid screening of molecular markers in large amount of tumours possible. Because only a small tissue sample of each tumour is punched on an array, the question has arisen about the representativeness of TMA when studying markers that are expressed in only a small proportion of cells. For this reason, we wanted to compare cyclin A expression on TMA and on traditional large sections. Two breast cancer TMAs were constructed of 200 breast tumours diagnosed between 1997-1998. TMA slides and traditional large section slides of these 200 tumours were stained with cyclin A antibody and analysed by two independent readers. The reproducibility of the two readers' results was good or even very good, with kappa values 0.71-0.87. The agreement of TMA and large section results was good with kappa value 0.62-0.75. Cyclin A overexpression was significantly (P<0.001) associated with oestrogen receptor and progesterone receptor negativity and high grade both on TMA and large sections. Cyclin A overexpression was significantly associated with poor metastasis-free survival both on TMA and large sections. The relative risks for metastasis were similar on TMA and large sections. This study suggests that TMA technique could be useful to study histological correlations and prognostic significance of cyclin A on breast cancer on a large scale.

Occurrence of oral mucosal lesions, the influence of tobacco habits and an estimate of treatment time in an adult Swedish population.

A randomly selected sample of adult subjects living in a Swedish county was examined for the presence of oral mucosal lesions. Nine hundred twenty (920, 95%) of the selected sample of 967 subjects, comprising approximately 0.75% of the total adult population, were examined; lesions were registered in 596 of the 920. The registered prevalence levels were very similar to earlier reported data from Sweden. Further, the relationship between tobacco habits and mucosal lesions was analyzed and the time needed for treatment of the lesions was estimated. A positive correlation could be demonstrated between tobacco use and leukoplakia, frictional white lesion, coated tongue, hairy tongue and excessive melanin pigmentation, while a negative correlation was observed for geographic tongue and aphthous ulcers. Approximately 70% of the lesions were associated with local irritants (e.g. dentures, tobacco, cheek and lip biting etc.). The estimated mean time required for registration and management of oral mucosal lesions in the studied group of adults was 24 min per individual.

Prevalence of previous endodontic treatment, technical standard and occurrence of periapical lesions in a randomly selected adult, general population.

A random sample of 967 subjects selected from the total population in a Swedish county were examined radiographically regarding prevalence and quality of endodontic treatment and occurrence of periapical lesions. The relationship between the technical standard of endodontic treatment and the occurrence of periapical lesions was also analyzed. Of the selected individuals, 95% attended examination (751 dentate and 169 edentulous individuals). Of the 17,430 teeth examined, 1,492 (8.6%) were endodontically treated. Approximately 70% of the treated root canals were inadequately obturated; 10% showed excess of root filling beyond the apex. The prevalence of periapical lesions was 2.9%, and 24.5% of the endodontically treated roots demonstrated periapical lesions. Root fillings ending more than 2 mm from apex had a significantly lower frequency of periapical lesions than root fillings ending within 2 mm of the apex. No difference in the frequency of periapical lesions was found between properly and improperly obturated root canals. Excess of root filling material beyond the apex was related to a significantly higher frequency of periapical lesions.

Prevalence of signs and symptoms of dysfunction in the masticatory system: an epidemiologic study in an adult Swedish population.

The prevalence of signs and symptoms of dysfunction in the masticatory system was studied by questionnaire and clinically in a randomly selected age- and sex-stratified sample of Swedish adults as a part of an epidemiologic survey on oral health. The prevalence of dental wear was also registered. There were 920 subjects examined, representing a participation rate of 95%. The questions and the clinical examination parameters were in accordance with those suggested by Helkimo in 1973. Reported symptoms decreased with age, while clinical signs increased. The prevalence of severe dysfunction was extremely low. The degree of dental wear increased with age, but extensive wear was extremely rare in women.