Contribution of fine particulate matter sources to indoor exposure in bars, restaurants, and cafes

This study investigated the contribution of sources and establishment characteristics, on the exposure to fine particulate matter (PM(2.5)) in the non-smoking sections of bars, cafes, and restaurants in central Zurich. PM(2.5)-exposure was determined with a nephelometer. A random sample of hospitality establishments was investigated on all weekdays, from morning until midnight. Each visit lasted 30 min. Numbers of smokers and other sources, such as candles and cooking processes, were recorded, as were seats, open windows, and open doors. Ambient air pollution data were obtained from public authorities. Data were analysed using robust MM regression. Over 14 warm, sunny days, 102 establishments were measured. Average establishment PM(2.5) concentrations were 64.7 microg/m(3) (s.d. = 73.2 microg/m(3), 30-min maximum 452.2 microg/m(3)). PM(2.5) was significantly associated with the number of smokers, percentage of seats occupied by smokers, and outdoor PM. Each smoker increased PM(2.5) on average by 15 microg/m(3). No associations were found with other sources, open doors or open windows. Bars had more smoking guests and showed significantly higher concentrations than restaurants and cafes. Smokers were the most important PM(2.5)-source in hospitality establishments, while outdoor PM defined the baseline. Concentrations are expected to be even higher during colder, unpleasant times of the year. PRACTICAL IMPLICATIONS: Smokers and ambient air pollution are the most important sources of fine airborne particulate matter (PM(2.5)) in the non-smoking sections of bars, restaurants, and cafes. Other sources do not significantly contribute to PM(2.5)-levels, while opening doors and windows is not an efficient means of removing pollutants. First, this demonstrates the impact that even a few smokers can have in affecting particle levels. Second, it implies that creating non-smoking sections, and using natural ventilation, is not sufficient to bring PM(2.5) to levels that imply no harm for employees and non-smoking clients. [Authors]

Evaluation of clinician-operated sonography and fine-needle aspiration in the assessment of salivary gland tumours.

OBJECTIVES: To evaluate the combination of ultrasound (US) + fine-needle aspiration (FNA) in the assessment of salivary gland tumours in the hands of the otolaryngologist. DESIGN: A retrospective review of case notes was performed. SETTING: Two university teaching hospitals in Switzerland. PARTICIPANTS: One hundred and three patients with a total of 106 focal masses of the salivary glands were included. Clinician-operated US + FNA were the first line of investigation for these lesions. All patients underwent surgical excision of the lesion, which allowed for confirmation of diagnosis by histopathology in 104 lesions and by laboratory testing in two lesions. MAIN OUTCOME MEASURES: Primary--diagnostic accuracy in identifying true salivary gland neoplasms and detecting malignancy. Secondary--predicting an approximate and specific diagnosis in these tumours. RESULTS: The combination of US + FNA achieved a diagnostic accuracy of 99% in identifying and differentiating true salivary gland neoplasms from tumour-like lesions. In detecting malignancy, this combination permitted an accuracy of 98%. An approximate diagnosis was possible in 89%, and a specific diagnosis in 69% of our patients. CONCLUSIONS: Due to economic factors and a high diagnostic accuracy, the combination of US + FNA represents the investigation method of choice for most salivary gland tumours. We suggest that the otolaryngologist be employed in carrying out these procedures, as is already the rule in other medical specialties, while computed tomography and magnetic resonance imaging should be reserved to those few lesions, which cannot be delineated completely by sonography.

Comparison of the organization and fine structure of a chicken and a Xenopus laevis vitellogenin gene.

The structural organization and the coding nucleotide sequence of the Xenopus laevis A2 and the chicken major vitellogenin genes have been compared. Both genes show the same exon-intron organization. However, the degree of homology between the nucleotide and derived amino acid sequences varies extensively along the genes. Several of the 35 exons are quite similar, and a unique cysteine motif in the lipovitellin II domain is conserved between the two genes. In contrast, one internal region is quite divergent. Part of this region encodes phosvitin, which appears to have evolved rapidly by both point mutations and duplications of serines or short other amino acid stretches. On the basis of these observations, we discuss the possible mechanism of evolution of phosvitin in vertebrates.

Fine structural variations of alphabeta TCRs selected by vaccination with natural versus altered self-antigen in melanoma patients

Immunotherapy of cancer is often performed with altered "analog" peptide Ags optimized for HLA class I binding, resulting in enhanced immunogenicity, but the induced T cell responses require further evaluation. Recently, we demonstrated fine specificity differences and enhanced recognition of naturally presented Ag by T cells after vaccination with natural Melan-A/MART-1 peptide, as compared with analog peptide. In this study, we compared the TCR primary structures of 1489 HLA-A*0201/Melan-A26-35-specific CD8 T cells derived from both cohorts of patients. Although a strong preference for TRAV12-2 segment usage was present in nearly all patients, usage of particular TRAJ gene segments and CDR3 composition differed slightly after vaccination with natural vs analog peptide. Moreover, TCR β-chain repertoires were broader after natural than analog peptide vaccination. In all patients, we observed a marked conservation of the CDR3β amino acid composition with recurrent sequences centered on a glycyl-leucyl/valyl/alanyl-glycyl motif. In contrast to viral-specific TCR repertoires, such "public" motifs were primarily expressed by nondominant T cell clonotypes, which contrasted with "private" CDR3β signatures frequently found in T cell clonotypes that dominated repertoires of individual patients. Interestingly, no differences in functional avidity were observed between public and private T cell clonotypes. Collectively, our data indicate that T cell repertoires generated against natural or analog Melan-A peptide exhibited slightly distinct but otherwise overlapping and structurally conserved TCR features, suggesting that the differences in binding affinity/avidity of TCRs toward pMHC observed in the two cohorts of patients are caused by subtle structural TCR variations.

Adam Politzer (1835-1920) et l'histoire de l'otologie moderne

Problématique et plan de l'ouvrage Au début des années 1970, apparaît une nouvelle approche de l'histoire qui proclame le primat de la démarche scientifique sur les options philosophiques ou le primat de la démarche intellectuelle sur les documents historiques. L'historien va dorénavant échafauder des hypothèses qu'il soumet ensuite à vérification et qu'il rectifie en conséquence. En effet, il n'y a pas de faits historiques en soi, qu'il suffirait d'extraire des documents et de raccorder à d'autres faits pour constituer une suite chronologique naturelle. L'histoire thématique s'impose en analysant le fonctionnement et la contextualisation au détriment de la pure description des faits. Les histoires ne sont jamais équivalentes : elles peuvent expliquer les choses différemment ou donner plus d'importance à une observation particulière et en laisser d'autres dans l'ombre. Cinq problématiques principales se dégagent de la vie de Politzer, problématiques assimilables à cinq métiers qui seront détaillés dans ce travail : le métier de clinicien, le métier de chercheur, le métier d'enseignant, le métier d'historien et le métier d'artiste et collectionneur d'art. Trois de ces métiers font partie intégrante de celui de médecin qui fut l'occupation principale de Politzer durant la plus grande partie de sa vie. Chaque problématique est développée sur le même principe : élaboration du contexte historique et particulier, description des données observables relatives à Politzer, établissement d'un lien entre le contexte et les composantes vérifiables pour en tirer une conclusion, ou plutôt démontrer la véracité de la problématique, tout en gardant à l'esprit que les faits ont toujours le dernier mot face aux théories. Cette démarche scientifique va permettre de mieux comprendre l'importance et la place prises par Politzer dans l'histoire de l'otologie et la société viennoise de la fin du XIXe siècle. L'ouvrage va s'articuler autour de ces cinq problématiques étudiées. Après une introduction générale, un chapitre biographique présente les origines de la famille Politzer et ses années de jeunesse. Il est complété par un autre chapitre sur ses années d'études de médecine avant d'entrer dans le vif du sujet des différents métiers de Politzer. Dans le chapitre concernant Politzer enseignant, une place toute particulière est accordée à la naissance de l'otologie, en tant que spécialité médicale à part entière, dans la première moitié du XIXe siècle. Cette étape fut importante, car elle permit à l'otologie de véritablement s'épanouir dans la seconde moitié du XIXe siècle. Cela aide à situer avec précision les travaux scientifiques entrepris et publiés par Politzer. Avant la conclusion, deux petits chapitres biographiques présentent la vie privée de Politzer et ses descendants. Une chronologie biographique et une bibliographie la plus exhaustive possible des travaux de Politzer sont ajoutées en annexe accompagnées de documents choisis et écrits par et sur Politzer. Deux de ces textes reflètent plus particulièrement certaines prises de position de Politzer concernant l'importance de l'otologie.