Background: Long-term persistence of C. burnetii in infected animals was established in the 1950s and 60s, but the implications for human Q fever are not fully explored. Aim: To compare the ...prevalence of markers of infection in a cohort of Q fever patients in Australia (up to 5 years after infection) with those in the 1989 Birmingham cohort (12 years after infection). Design: Case follow-up study. Methods: C. burnetii was tested for by: (i) antibodies to Phase 1 and 2 antigens in the three immunoglobulin classes; (ii) detection of DNA in bone marrow and peripheral blood mononuclear cells by PCR assays directed against several different targets in the genome; and (iii) attempts to isolate coxiellas in cell culture or mice from PCR-positive samples. Amplicon specificity was verified by fluorometric probing and by sequencing. Cross-contamination was excluded by extensive use of non-template controls, and in particular by the use of certain IS1111a target sequences. Results: Irrespective of clinical state, both groups remained seropositive, principally exhibiting medium levels of IgG antibody against C. burnetii Phase 2 antigen. C. burnetii genomic DNA was detected by PCR in 65% of bone marrow aspirates from Australian patients and ∼88% of Birmingham patients. No coxiella were isolated from PCR positive samples. Discussion: We propose a provisional model for persistence. In Q fever without sequelae, the process is largely confined to the bone marrow. In Q fever fatigue syndrome (QFS), it is modulated by the patient's immunogenetic background to give higher levels of coxiella genomes in bone marrow and increased shedding into the peripheral blood. In Q fever endocarditis, late pregnancy, or during iatrogenic or other immunosuppression, the multiplication cycle is prolonged, and a potential source of live organisms.
The use of proteolytic enzymes to improve the cleaning efficacy of washing powders was introduced in the mid 1960s. Many microbial enzymes are known to be potent respiratory sensitizers but ...previously there has been only one case of occupational asthma associated with workplace exposure in a healthcare worker.
To report two cases of occupational asthma associated with exposure to biological enzymes in health-care workers and related occupational cases.
Reporting of clinical case reports from three different work places.
One case of occupational asthma and three other cases with work-related asthma or rhinitis occurred in one workplace. A single case of probable occupational asthma presented at a second workplace with another case of work-related asthma at a third workplace. Exposures occurred in areas used for cleaning medical instruments and endoscopy suites. Hygiene measurements confirmed the potential for exposure. Control measures were not in place and recognition of the hazard was missing in these workplaces.
Detergent enzymes when used in healthcare settings should be recognized as potential respiratory sensitizers. Healthcare institutions and professional bodies that recommend the use of detergent enzymes should review their risk assessments to ensure that the most appropriate methods for preventing or reducing exposure are in place.
Occupational asthma (OA) remains common; 1 in 10 cases of adult-onset asthma is due to work. Health outcomes are better with early diagnosis, but there is considerable delay, largely due to lack of ...enquiry about work effect in primary care. National guidelines (2008) recommend asking two screening questions, which together have a high sensitivity in identifying OA.
To audit how working-age asthmatics are currently screened for OA in a local primary care population.
An audit of the electronic patient records of working-age asthmatics, from four Birmingham primary care practices was undertaken. Practice-level data (list size, gender, prevalence of asthma and OA and socio-economic status) and patient-level data (gender, age, onset, occupation and work-effect enquiry and lung function) were collected.
The total practice population was 27,295 of which 17,564 (64%) were of working age. The audit sample was 396 of whom 49% were male. The prevalence of asthma in working-age adults was 12% (8-15%) and the prevalence of OA in working-age asthmatics was 0.3% (0-0.8%). Occupation was recorded in only 55/396 (14%) cases with very few (2) documented within the asthma-review template. Occupation was only recorded in 13/55 adult-onset asthmatics in high-risk occupations. Of 396, 9 (2%) had any work-effect enquiry and 4 patients had work-effect enquiry at diagnosis in those with traceable notes (n = 117).
The prevalence of OA was low, suggesting under-diagnosis plus under-reporting in primary care. Occupation and work-effect enquiry is lacking despite guidelines for identifying OA. Existing electronic templates for recording asthma review could be modified to include these elements.
Objectives:Misclassification of exposure related to the use of central sites may be larger for ultrafine particles than for particulate matter ⩽2.5 μm and ⩽10 μm (PM2.5 and PM10) and may result in ...underestimation of health effects. This paper describes the relative strength of the association between outdoor and indoor exposure to ultrafine particles, PM2.5 and PM10 and lung function.Methods:In four European cities (Helsinki, Athens, Amsterdam and Birmingham), lung function (forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and peak expiratory flow (PEF)) was measured three times a day for 1 week in 135 patients with asthma or chronic obstructive pulmonary disease (COPD), covering study periods of >1 year. Daily concentrations of particle number, PM2.5 and PM10 were measured at a central site in each city and both inside and outside the subjects’ homes.Results:Daily average particle number concentrations ranged between 2100 and 66 100 particles/cm3. We found no association between 24 h average particle number or particle mass concentrations and FVC, FEV1 and PEF. Substituting home outdoor or home indoor concentrations of particulate air pollution instead of the central site measurements did not change the observed associations. Analyses restricted to asthmatics also showed no associations.Conclusions:No consistent associations between lung function and 24 h average particle number or particle mass concentrations were found in panels of patients with mild to moderate COPD or asthma. More detailed exposure assessment did not change the observed associations. The lack of association could be due to the high prevalence of medication use, limited ability to assess lagged effects over several days or absence of an effect.
This paper reports the first measurement using the NOvA detectors of nu sub(mu) disappearance in a nu sub(mu) beam. The analysis uses a 14 kton-equivalent exposure of 2.74x10 super(20) ...protons-on-target from the Fermilab NuMI beam. Assuming the normal neutrino mass hierarchy, we measure (ProQuest: Formulae and/or non-USASCII text omitted) and sin super(2)theta sub(23) in the range 0.38-0.65, both at the 68% confidence level, with two statistically degenerate best-fit points at sin super(2)theta sub(23)=0.4 3 and 0.60. Results for the inverted mass hierarchy are also presented.
Asthmatic subjects exposed to sulphur dioxide at rest show a reduction in parasympathetic tone while normal subjects show an increase in tone, 26 perhaps mediated through rapidly adapting receptors ...27 in the larynx. 28 While such an increase in vagal tone in normal subjects in response to an inhaled irritant can be construed as bronchoprotective, this apparently paradoxical asthmatic response may be due to an initial induction of neurogenic inflammation by the irritant followed by vagal inhibition. 26 Once upper airway hyperresponsiveness (on the background of the change in autonomic preset) is established, the absence of quick recovery from an initiating episode could result in this autonomic preset becoming persistent.
The present birth cohort study investigated whether or not childhood wheeze and asthma are associated with parental exposure to occupational sensitisers that cause asthma. Parental occupation, from ...the Avon Longitudinal Study of Parents and Children (ALSPAC), was related to wheeze, asthma, ventilatory function, airway responsiveness and atopic sensitisation in children aged 0-102 months. Occupation was recorded for 11,193 mothers and 9,473 fathers antenatally, and for 4,631 mothers and 5,315 fathers post-natally. Childhood respiratory outcomes were not associated with parental occupational exposure to diisocyanates, glues/resins, dyes, animal dust, solder, enzymes and wood dust. Maternal post-natal occupational exposure to latex and/or biocides/fungicides increased the likelihood of childhood wheeze and asthma. High levels of latex or biocide/fungicide exposure were associated with an OR (95% CI) of 1.26 (1.07-1.50) and 1.22 (1.02-2.05), respectively, for wheezing up to 81 months. Combined maternal latex and biocide/fungicide exposure increased the likelihood of childhood wheeze (1.22 (1.03-1.43)) and asthma. High paternal occupational flour dust exposure was associated with an increased likelihood of wheeze after 30 months (2.31 (1.05-5.10)) and asthma by 91 months (3.23 (1.34-7.79)). Maternal occupational exposure to latex and/or biocides and paternal exposure to flour dust increases the risk of childhood asthma. Further studies in this area are justified.
OBJECTIVES: To determine the presence and magnitude of any relation between short term variations in ambient concentrations of particulate matter under 10 microns in diameter (PM10) and hospital ...admissions and mortality in Birmingham, United Kingdom. To find the relative risk associated with various concentrations of PM10, and to estimate the potential public health benefit of reducing PM10 to below various thresholds. METHODS: Retrospective ecological study. Air pollution data were taken from a national network monitoring station between 1 April 1992 and 31 March 1994, and weather data for the same period from the University of Birmingham Weather Service. Daily total hospital admissions for the same period for asthma, bronchitis, pneumonia, chronic obstructive pulmonary disease (COPD), acute ischaemic heart disease, acute cerebrovascular disease, all respiratory conditions, and all circulatory conditions were obtained from the West Midlands Regional Health Authority, as well as daily total deaths from 1 April 1992 to 31 December 1994 for chronic obstructive pulmonary disease, pneumonia, all respiratory diseases, all circulatory diseases, and all causes. Multiple linear regression models were constructed after adjusting for confounding factors (day of week, month, linear trend, relative humidity, and temperature). Relative risk of admission at various thresholds of PM10 was calculated with the model, by comparing risk of admission over the threshold with mean risk of admission over the whole period. Potential public health benefits at various thresholds were calculated with the model to predict the number of admissions of deaths that could be saved if, on each day that the PM10 had exceeded that threshold, it had instead been kept at the threshold level. RESULTS: Significant associations were found between all respiratory admissions, cerebrovascular admissions, and bronchitis admissions and PM10 on the same day. Pneumonia, all respiratory admissions, and asthma admissions were significantly associated with the mean PM10 values for the past three days. Deaths from COPD, all circulatory deaths, and all causes mortality were significantly associated with PM10 24 hours previously, and COPD deaths also with PM10 on the same day. The effect of a 10 micrograms/m3 rise in PM10 was estimated to represent a 2.4% increase in respiratory admissions, a 2.1% increase in cerebrovascular admissions, and a 1.1% increase in all causes mortality. In a population of 1 million, this would represent 0.5 extra respiratory admissions and 0.3 extra deaths. The increase in relative risk was linear without evidence of a threshold. The impact of reducing PM10 to below 70 micrograms/m3 would be small, representing less than 0.1% of respiratory admissions and 0.2% all causes mortality. The impact would be greater at lower thresholds. CONCLUSION: Ambient outdoor concentrations of PM10 in the United Kingdom are significantly associated with several indicators of acute health effect. These associations are similar to and consistent with other studies. However, the estimated size of the public health effect is small, accounting for only a small proportion of hospital admissions and mortality over a two year period.
The prolonged use or abuse of voice may lead to vocal fatigue and vocal fold tissue damage. School teachers routinely use their voices intensively at work and are therefore at a higher risk of ...dysphonia.
To determine the prevalence of voice disorders among primary school teachers in Lagos, Nigeria, and to explore associated risk factors.
Teaching and non-teaching staff from 19 public and private primary schools completed a self-administered questionnaire to obtain information on personal lifestyles, work experience and environment, and voice disorder symptoms. Dysphonia was defined as the presence of at least one of the following: hoarseness, repetitive throat clearing, tired voice or straining to speak.
A total of 341 teaching and 155 non-teaching staff participated. The prevalence of dysphonia in teachers was 42% compared with 18% in non-teaching staff. A significantly higher proportion of the teachers reported that voice symptoms had affected their ability to communicate effectively. School type (public/private) did not predict the presence of dysphonia. Statistically significant associations were found for regular caffeinated drink intake (odds ratio OR = 3.07; 95% confidence interval CI: 1.51-6.62), frequent upper respiratory tract infection (OR = 3.60; 95% CI: 1.39-9.33) and raised voice while teaching (OR = 10.1; 95% CI: 5.07-20.2).
Nigerian primary school teachers were at risk for dysphonia. Important environment and personal factors were upper respiratory infection, the need to frequently raise the voice when teaching and regular intake of caffeinated drinks. Dysphonia was not associated with age or years of teaching.
We report an improved measurement of ν(μ) disappearance over a distance of 735 km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a ν(μ)-enhanced configuration. From a total ...exposure of 2.95×10(20) protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of Δm2=2.62(-0.28)(+0.31)(stat)±0.09(syst)×10(-3) eV2 and constrain the ν(μ) mixing angle sin2(2θ)>0.75 (90% C.L.). These values are in agreement with Δm2 and sin2(2θ) measured for ν(μ), removing the tension reported in P. Adamson et al. (MINOS), Phys. Rev. Lett. 107, 021801 (2011)..
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