Improved recovery of Listeria monocytogenes from stainless steel and polytetrafluoroethylene surfaces using air/water ablation.

AIMS: To develop a gentle ablation technique to recover Listeria monocytogenes biofilms from stainless steel (SS) and polytetrafluoroethylene (PTFE) surfaces by using compressed air and water injection. METHODS AND RESULTS: Biofilms were grown for 4, 24 and 48 h or 7 days and a compressed air and water flow at 2, 3 and 4 bars was applied for cell removal. Collected cells were quantified for total/dead by staining with SYTO 9/PI double staining and cultivable populations were determined by plating onto brain heart infusion (BHI) agar, while coupon surfaces also were stained with DAPI to quantify in situ the remaining cells. The recovery efficiency was compared to that of conventional swabbing. Results showed that the air/water ablation is able to collect up to 98·6% of cells from SS surfaces while swabbing only recovered 11·2% of biofilm. Moreover, air/water ablation recovered 99·9% of cells from PTFE surfaces. CONCLUSIONS: The high recovery rate achieved by this technique, along with the fact that cells were able to retain membrane integrity and cultivability, indicate that this device is suitable for the gentle recovery of viable L. monocytogenes biofilm cells. SIGNIFICANCE AND IMPACT OF THE STUDY: This work presents a highly efficient technique to remove, collect and quantify L. monocytogenes from surfaces commonly used in the food industry, which can thus serve as an important aid in verifying cleaning and sanitation as well as in reducing the likelihood of cross-contamination events.

[The prevalence of chronic obstructive pulmonary disease and asthma. A cross-sectional study]. / Prevalencia de la enfermedad pulmonar obstructiva crónica y del asma. Estudio transversal.

Four hundred sixty-seven patients between 35 and 65 years of age were studied, all taken from a random sample of the population of Health Area 5 of the Valencian Community. Figures for respiratory symptoms, smoking, previous lung disease, professional activity and lung function were obtained through questionnaires and spirometry. The prevalence of asthma found was 2.78% (C.I. 2.76-2.79); chronic bronchitis was 4.07% (C.I. 2.37-5.77) and airflow limitation was 6.4% (C.I. 4.5-8.3). Smokers represented 33.2% of the sample. A significant association was found between the level of intensity of symptoms and lung function. There were no differences between smokers and non smokers with respect to FEV1%. An association between workplace exposure and spirometry was found only for FEV1/FVC%.

Airway responsiveness to acetaldehyde in patients with asthma: relationship to methacholine responsiveness and peak expiratory flow variation.

BACKGROUND: Although airway hyperresponsiveness to inhaled acetaldehyde has been documented in Japanese patients with asthma, the response to this bronchoconstrictor agent has never been studied in Caucasians. OBJECTIVES: The objectives of the study were to determine differences in airway responsiveness to acetaldehyde between asthmatic and healthy subjects, and to examine the relationship between acetaldehyde responsiveness and the variability of peak expiratory flow (PEF). METHODS: The response to methacholine and acetaldehyde challenges was measured in 81 non-smoking adults (61 asthmatics and 20 normal controls). Subjects recorded PEF morning and evening for 14 days. The response to both bronchoconstrictor agents was measured by the PC20 (provocative concentration required to produce a 20% fall in FEV1). PEF variation was expressed as amplitude percentage mean, and as low percentage best (lowest PEF expressed as a percentage of the best PEF recorded). RESULTS: The two types of challenge yielded a similarly high level of sensitivity (100% for methacholine and 92% for acetaldehyde) and specificity (90 and 100%, respectively) to distinguish between asthma and controls. Asthmatic subjects were on average 265-fold less sensitive to acetaldehyde than to methacholine. PC20 acetaldehyde correlated weakly but significantly with both indices of PEF variation (amplitude percentage mean: rho = - 0.36, P = 0. 004; low percentage best: rho = 0.42, P = 0.001). CONCLUSIONS: These results indicate that airway hyperresponsiveness to acetaldehyde is a sensitive and specific indicator for separating asthmatic and normal subjects. Airway responsiveness to methacholine or acetaldehyde and PEF variation are not reflecting the same pathophysiological process in the airways.

[Helicobacter pylori: 6-day triple therapy in duodenal ulcer]. / Helicobacter pylori: triple terapia de 6 días en el ulcus duodenal.

OBJECTIVES: To find the effectiveness of short-term eradication treatment of Helicobacter pylori in the duodenal ulcer. DESIGN: Intervention study, open controlled, randomised with parallel groups. SETTING: Three Health Centres in the city of Valencia. PATIENTS: Patients with a duodenal ulcer diagnosis and a Helicobacter pylori infection who attended the Primary Care physician. INTERVENTION: The study group (48 patients) was treated for six days with the triple therapy: Amoxycillin, Clarithromycin and Omeprazole. The control group (40 patients) was treated with Omeprazole for six weeks. MEASUREMENTS AND MAIN RESULTS: The observance period lasted a year, after which the Elisa test was conducted. Eradication was successful for 65% of those treated with the triple therapy, but for only 30% of those treated with monotherapy. The consumption of medication for the ulcer during the year of observance was almost three times greater in the group treated with monotherapy than in the triple-therapy group. CONCLUSIONS: Eradicative triple therapy was shown to be more effective and efficient than monotherapy. It is feasible to use it in Primary Care. Eradicative triple therapy is not advisable within six days: a longer treatment period should be employed with this recommendable therapy.

[Study of 2 food poisoning outbreaks in Mora (Toledo) with the same source of infection]. / Investigación de dos brotes de toxiinfección alimentaria en Mora (Toledo) con una fuente de infección común.

BACKGROUND: The occurrence of an outbreak needs an immediate investigation, because on it depends the necessary measures to control the spread of the epidemic, and it is also the way of knowing the causal factor. We present the results of the investigation of two food poisoning outbreaks (outbreak A and outbreak B) occurred in Mora (Toledo). Both outbreaks were reported at the same time, the source of infection was the same and the total number of exposed people was 620. METHODS: A case-control study was carried out. A standardised questionnaire for food poisoning outbreaks was used to collect the data. Data were analysed using classic methods and also logistic regression models. RESULTS: A total of 236 individuals were interviewed (119 for outbreak A and 117 for outbreak B), 146 of them were cases (73 in each outbreak). The mean incubation period was of 26.18 (+/- 12.35) and 25.2 (+/- 19.9) hours respectively. The main symptoms were diarrhoea, fever and abdominal pain. The mean age of the cases was 43.42 (+/- 17.03) years old for outbreak A and 42.4 (+/- 19.9) for outbreak B. The statistical analysis showed a significant association between the intake of cake and the disease (adjusted odds ratio = 25.00; 95% confidence interval = 6,4996.15 for outbreak A and adjusted odds ratio = 64.62; 95% confidence interval = 8.10-515.3 for outbreak B). We also obtained a laboratory confirmation showing the presence of Salmonella Entérica I, Infantis 6.7:r:1.5 in samples of cases, cake and samples of the person who prepared the cake. CONCLUSIONS: The logistic regression model, used for the analysis was useful to detect and summarise data in a more efficient manner than simple stratified analysis. The collaboration of the Primary Health Care professionals contributed to the success of the investigation.