Endovascular Treatment of Occlusive Lesions in the Aortic Bifurcation with Kissing Polytetrafluoroethylene-Covered Stents.

PURPOSE: To determine the clinical outcomes of polytetrafluoroethylene covered balloon expandable stents (CBESs) in occlusive lesions of the aortic bifurcation in a kissing stent configuration. MATERIALS AND METHODS: The study included 69 consecutive patients (29 men, 40 women) who underwent kissing stent procedures with CBESs between January 2003 and April 2009 in a single center. Patients who were previously treated with a CBES were excluded. Follow-up consisted of clinical investigation and duplex ultrasound examination. RESULTS: The primary patency was 88.1% at 1 year and 71.5% at 4 years, with secondary patency rates of 88.1% and 75.3%, respectively. For patients receiving a stent for the first time, primary patency was 91.3% at 1 year and 77.1% at 4 years. For patients who had received previous stents, patency was 83.6% at 1 year and 65.2% at 4 years (P = .83). There were no differences in secondary patency and freedom from target lesion reintervention (TLR). Loss of primary patency was mainly caused by stent occlusions (14 cases [78%]). The freedom from TLR at 4 years was 76.8%. CONCLUSIONS: Patency rates and freedom from TLR of CBESs in the kissing stent configuration with up to 4 years of follow-up were satisfying and mainly affected by stent occlusions. Studies focusing on optimizing stent configuration and medical care to reduce the incidence of thrombosis are indicated to improve results further.

Human exposure to endotoxins and fecal indicators originating from water features.

Exposure to contaminated aerosols and water originating from water features may pose public health risks. Endotoxins in air and water and fecal bacteria in water of water features were measured as markers for exposure to microbial cell debris and enteric pathogens, respectively. Information was collected about wind direction, wind force, distance to the water feature, the height of the water feature and the tangibility of water spray. The mean concentration of endotoxins in air nearby and in water of 31 water features was 10 endotoxin units (EU)/m(3) (Geometric Mean (GM), range 0-85.5 EU/m(3) air) and 773 EU/mL (GM, range 9-18,170 EU/mL water), respectively. Such mean concentrations may be associated with respiratory health effects. The water quality of 26 of 88 water features was poor when compared to requirements for recreational water in the Bathing Water Directive 2006/7/EC. Concentrations greater than 1000 colony forming units (cfu) Escherichia coli per 100 mL and greater than 400 cfu intestinal enterococci per 100 mL increase the probability of acquiring gastrointestinal health complaints. Regression analyses showed that the endotoxin concentration in air was significantly influenced by the concentration of endotoxin in water, the distance to the water feature and the tangibility of water spray. Exposure to air and water near water features was shown to lead to exposure to endotoxins and fecal bacteria. The potential health risks resulting from such exposure to water features may be estimated by a quantitative microbial risk assessment (QMRA), however, such QMRA would require quantitative data on pathogen concentrations, exposure volumes and dose-response relationships. The present study provides estimates for aerosolisation ratios that can be used as input for QMRA to quantify exposure and to determine infection risks from exposure to water features.

Application of a prediction model for work-related sensitisation in bakery workers.

Identification of work-related allergy, particularly work-related asthma, in a (nationwide) medical surveillance programme among bakery workers requires an effective and efficient strategy. Bakers at high risk of having work-related allergy were indentified by use of a questionnaire-based prediction model for work-related sensitisation. The questionnaire was applied among 5,325 participating bakers. Sequential diagnostic investigations were performed only in those with an elevated risk. Performance of the model was evaluated in 674 randomly selected bakers who participated in the medical surveillance programme and the validation study. Clinical investigations were evaluated in the first 73 bakers referred at high risk. Overall 90% of bakers at risk of having asthma could be identified. Individuals at low risk showed 0.3-3.8% work-related respiratory symptoms, medication use or absenteeism. Predicting flour sensitisation by a simple questionnaire and score chart seems more effective at detecting work-related allergy than serology testing followed by clinical investigation in all immunoglobulin E class II-positive individuals. This prediction based stratification procedure appeared effective in detecting work-related allergy among bakers and can accurately be used for periodic examination, especially in small enterprises where delivery of adequate care is difficult. This approach may contribute to cost reduction.

A cross-sectional study among detergent workers exposed to liquid detergent enzymes.

OBJECTIVES: To investigate sensitisation and respiratory health among workers who produce liquid detergent products and handle liquid detergent enzymes. METHODS: We performed a cross-sectional study among 109 eligible workers of a detergent products plant. 108 were interviewed for respiratory and allergic symptoms and 106 blood samples were taken from them to examine sensitisation to enzymes. Those sensitised to > or = 1 enzymes were referred for clinical evaluation. Workers and representatives were interviewed to characterise exposure qualitatively and estimate exposure semi-quantitatively. Workers were classified into three exposure groups with varying exposure profiles to enzymes, based on frequency, duration, and level of exposure. RESULTS: Workers were exposed to proteases, alpha-amylase, lipase and cellulase. The highest exposures occurred in the mixing area. Liquid spills with concentrated enzyme preparations and leakage of enzymes during weighing, transportation and filling were causing workplace contaminations and subsequently leading to both dermal and inhalation exposure for workers. Workers with the highest exposures reported significantly more work-related symptoms of itching nose (prevalence ratio (PR) = 4.2, 95% CI 1.5 to 12.0) and sneezing (PR = 4.0, 95% CI 1.5 to 10.8) and marginally significant more symptoms of wheezing (PR = 2.9, 95% CI 0.9 to 8.7) compared with the least exposed group. Fifteen workers (14.2%) were sensitised to > or = 1 enzymes. A marginally statistically significant gradient in sensitisation across the exposure categories was found (p = 0.09). There was a clinical case of occupational asthma and two others with probable occupational rhinitis. CONCLUSIONS: Workers exposed to liquid detergent enzymes are at risk of developing sensitisation (14%) and respiratory allergy.

An assessment of dermal exposure to semi-synthetic metal working fluids by different methods to group workers for an epidemiological study on dermatitis.

BACKGROUND: Assessment of exposure assessment to metal working fluids (MWF) has almost exclusively focused on inhalation exposure. AIMS: To assess levels of, and factors affecting, dermal and inhalation exposure to semi-synthetic MWF, and to identify suitable dermal exposure grouping schemes among metal workers for an epidemiological survey on dermatitis of hands, forearms, and head. METHODS: A cross-sectional survey was conducted in four metal working machining departments of a truck manufacturing plant, estimating dermal and inhalation exposure levels to semi-synthetic metal working fluids (SMWF) in machine operators. Dermal exposure levels to SMWF were estimated by three different methods for dermal exposure assessment (VITAE, surrogate skin pad method, and a semi-quantitative dermal exposure assessment method (DREAM)). RESULTS: The identified factors affecting dermal exposure were similar for the three methods, although differences were found for estimated variability in dermal exposure levels between groups, within groups (among workers), and from day to day. With the VITAE method differences in exposure levels were detected between workers that were not detected with the surrogate skin pad method, and only partly with the DREAM method. CONCLUSIONS: Considering the additional effort and costs that use of the VITAE method entailed, the observational semi-quantitative DREAM method appeared to be more efficient for grouping of dermal exposure levels for the epidemiological study on dermatitis.

Fungal extracellular polysaccharides, beta (1-->3)-glucans and culturable fungi in repeated sampling of house dust.

Fungal exposure inside homes has been associated with adverse respiratory symptoms in children and adults. While fungal assessment has traditionally relied upon questionnaires, fungal growth on culture plates and spore counts, new immunoassays for extracellular polysaccharides (EPS) and beta (1-->3)-glucans have enabled quantitation of fungal agents in house dust in a more timely and cost-effective manner, possibly providing a better measure of fungal exposure. We investigated associations among measurements of EPS, beta (1-->3)-glucans and culturable fungi obtained from 23 Dutch homes. From each home, dust samples were vacuumed from the living room floor twice during the Fall, Winter and Spring seasons for a total of six collections (every 6 weeks from October 1997 to May 1998). Samples were sieved and fine dust was analyzed for EPS from Aspergillus and Penicillium spp. combined, beta (1-->3)-glucans and culturable fungi. EPS was positively associated with glucan; an increase from the 25th to the 75th percentile of glucan concentration was associated with a 1.6-fold increase in EPS concentration (95% CI = 1.3 to 2.0; p < 0.01). The most significant variables associated with EPS and glucan concentrations were the surface type that was vacuumed and the concentration of total culturable fungi (in colony forming units (CFU)/g dust), with an increase in CFU/g from the 25th to the 75th percentile associated with a 1.3 (1.1-1.6)-fold increase in glucan and a 1.7 (1.3-2.2)-fold increase in EPS concentrations. In addition, the within-home variation of EPS levels were smaller than those between homes (25,646 U/g vs. 50,635 U/g), whereas the variation of glucan levels was similar within and between homes (1,300 vs. 1,205 micrograms/g). These positive associations suggest that house dust concentrations of beta (1-->3)-glucan, and particularly those of EPS, are good markers for the overall levels of fungal concentrations in floor dust which is a surrogate for estimating airborne fungal exposure.

Comparison of methods to assess airborne rat and mouse allergen levels. II. Factors influencing antigen detection.

Potential factors influencing antigen detection in immunoassays for measuring rat or mouse aeroallergen (i.e., assay setup, antigen specificities, standard extracts used, and antigen decay) were investigated in a three-country study (the UK, The Netherlands, Sweden). An inhibition enzyme immunoassay (EIA) setup gave nominal rat urinary allergen (RUA) sample values seven times higher than a sandwich EIA setup utilizing identical antibodies and standards. In immunoblotting experiments, pooled patient serum and polyclonal rabbit antibodies partly detected different rat antigens; monoclonal antibody specificity could not be determined. Immunoblot detection of mouse urinary antigens (MUA) by the polyclonal rabbit antibodies from all laboratories was similar. In both the RUA and the MUA assays, urinary antigen standards were detected with similar potency, except purified Rat n 1, which was an inefficient inhibitor in the RUA RAST inhibition. In the sandwich EIA RUA assays, a rat room-dust extract was detected with 700800-fold less sensitivity than rat urine, whereas in the RAST RUA assay, dust inhibited equally with rat urine. Simulated decay did not decrease the potency of urinary antigen in any assay. Thus, assay setup and choice of detection antibodies strongly influence the nominal allergen levels. We recommend the use of standardized and characterized antibodies and standard extracts in sandwich EIAs to measure airborne rodent urinary allergens.

Exposure of laboratory animal workers to airborne rat and mouse urinary allergens.

BACKGROUND: Laboratory animal workers are at high risk of developing occupational allergy. Little is known about the relationship between levels of exposure and the risk of developing laboratory animal allergy. Since laboratory animal work comprises a large number of different-often short lasting-tasks, it is of interest to assess which activities are associated with high, low or intermediate levels of allergen exposure. OBJECTIVE: To develop and evaluate highly sensitive immunoassays in order to quantify rat and mouse urinary allergens in airborne dust sampled during short-lasting tasks. METHODS: Personal air dust samples were taken during full-shift periods as well as during specific tasks in seven laboratory animal facilities. Two sandwich enzyme immunoassays were developed, using rabbit antisera against rat and mouse urinary proteins. The rabbit antibodies were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting and compared with IgE antibodies from sensitized laboratory animal workers. RESULTS: The rabbit antibodies were highly specific for rat and mouse urinary proteins and reacted with all IgE-binding allergens in either urinary protein preparation. The assays for rat and mouse urine were very sensitive, with detection limits of 0.075 ng/mL. The coefficient of variation of the analysis was 12.9% for both assays. Animal caretakers appeared to experience the highest exposure to aeroallergens. A large variation in exposure within jobs was found, due to differences between tasks performed during the sampling day and the facility worked at. The highest exposure levels were found during removal of contaminated bedding from the cages. However, rat and mouse allergen exposure levels during this task varied enormously between facilities, 1.1-158 ng eq/m3 and 0.63-2000 ng eq/m3, respectively. CONCLUSION: Both sandwich immunoassays are highly specific and sensitive and are able to identity tasks of relatively short duration with high, medium and low exposure to airborne rat and mouse urinary allergens.

Airborne levels of alpha-amylase allergens in bakeries.

BACKGROUND: In the baking industry the use of enzymes has increased throughout the 1980s. Several studies have reported sensitization and respiratory disorders among bakery workers caused by enzymes in dough improvers. Fungal alpha-amylase is the most frequently reported cause of allergy. alpha-Amylase allergen exposure levels in the bakery industry, however, have not yet been reported. OBJECTIVE: The main objective of this study was to quantify personal alpha-amylase exposure levels of bakery workers. METHODS: alpha-Amylase allergens were measured in 507 personal samples of airborne dust taken in bakeries by using a newly developed sandwich enzyme immunoassay with affinity-purified polyclonal rabbit IgG antibodies. A cascade impactor was used to estimate the size of dust particles carrying alpha-amylase allergens. RESULTS: The rabbit IgG antibodies used in the assay showed, in immunoblotting with commercially available alpha-amylase, a reaction profile very similar to that of IgE from sensitized bakers. The enzyme immunoassay appeared to be highly specific for fungal amylase. Allergen exposure levels varied considerably among bakery workers, depending on the type of bakery and job category (range, 0 to 40 ng/m3). In confectioneries no alpha-amylase allergens were detected. In other bakeries alpha-amylase exposure was only found for workers directly involved in dough making. Measurements of the particle size distribution in these bakeries showed that alpha-amylase allergens are most likely to be deposited in the nose and ciliated airways. CONCLUSION: This study shows that personal monitoring of fungal amylase allergen exposure in bakeries is possible. This permits the identification of high-risk tasks and allergen sources, as well as the study of exposure-response relationships.

Stent placement after iliac angioplasty: comparison of hemodynamic and angiographic criteria. Dutch Iliac Stent Trial Study Group.

PURPOSE: To assess the diagnostic value of angiography as a guideline for selective stent placement after percutaneous transluminal angioplasty (PTA) of the iliac artery. MATERIALS AND METHODS: Seventy-nine patients (100 iliac artery lesions) with intermittent claudication were treated with PTA and stent placement if they had a residual intraarterial mean pressure gradient of more than 10 mm Hg across the PTA site. Pre- and post-PTA angiograms were used to determine if stent placement was necessary for improvement of the initial result of PTA. Interobserver agreement was determined by using kappa statistics. Pearson correlation coefficients for the percentage of residual stenosis and the pressure gradient after angioplasty were calculated. Sensitivity and specificity of angiography with regard to secondary stent placement were calculated. RESULTS: Observer agreement on stenosis grade before angioplasty was good (mean kappa, 0.65). Agreement on angioplasty results was fair (mean kappa, 0.45). Agreement on selective stent placement on the basis of angiographic criteria was poor to fair (kappa = 0.21-0.62). Correlation between percentage stenosis and pressure gradient was low (Pearson coefficient, 0.01-0.17). The sensitivity and specificity of angiography were 45% and 63%, respectively. CONCLUSION: Angiography is inadequate for determination of a suboptimal angioplasty result. The decision to perform selective stent placement should be made on the basis of hemodynamic measurements.