Dental health in patients with and without HPV-positive oropharyngeal and tongue cancer

BackgroundHuman papilloma virus is associated with oral and oropharyngeal cancer. Our aim was to examine oral health in patients with oropharyngeal (OPSCC) and oral tongue cancer (OTSCC), expecting better oral health among OPSCC patients.Material and methodsFifty-five OPSCC patients with known HPV status and 59 OTSCC patients were randomly selected from a list of consecutive patients of the Helsinki University Hospital, Finland. Oral health was assessed from panoramic jaw radiographs. Total Dental Index (TDI) summarizing the dental health status was calculated and Finnish population study data were used for comparison. Descriptive statistics were used for analyses.ResultsPatients with HPV-positive OPSCC had higher periapical lesion index compared with HPV-negative OPSCC patients or with OTSCC patients. Residual roots were more common among OPSCC patients compared with OTSCC patients, because of their higher occurrence among HPV-negative OPSCC patients compared with OTSCC patients. Similarly, modified TDI score was significantly higher among OPSCC patients than among OTSCC patients, because of higher TDI score among HPV-negative OPSCC patients compared with OTSCC patients. OPSCC patients more often used a removable prosthesis than OTSCC patients. Dental health of the cancer patients was poorer when compared with the population data.ConclusionsOur study hypothesis was only partly confirmed. Periapical lesions were more prevalent among HPV-positive OPSCC patients, compared with the other groups. The number of residual roots was higher among HPV-negative subgroup. Thus, OPSCC patients had worse oral health parameters than OTSCC patients.Peer reviewe

Tenascin-C and fibronectin expression divide early stage tongue cancer into low- and high-risk groups

Background:Oral tongue squamous cell carcinoma (OTSCC) metastasises early, especially to regional lymph nodes. There is an ongoing debate on which early stage (T1-T2N0) patients should be treated with elective neck dissection. We need prognosticators for early stage tongue cancer. Methods: Mice immunisation with human mesenchymal stromal cells resulted in production of antibodies against tenascin-C (TNC) and fibronectin (FN), which were used to stain 178 (98 early stage), oral tongue squamous cell carcinoma samples. TenascinC and FN expression in the stroma (negative, moderate or abundant) and tumour cells (negative or positive) were assessed. Similar staining was obtained using corresponding commercial antibodies. Results: Expression of TNC and FN in the stroma, but not in the tumour cells, proved to be excellent prognosticators both in all stages and in early stage cases. Among early stages, when stromal TNC was negative, the 5-year survival rate was 88%. Correspondingly, when FN was negative, no cancer deaths were observed. Five-year survival rates for abundant expression of TNC and FN were 43% and 25%, respectively. Conclusions: Stromal TNC and, especially, FN expressions differentiate patients into low-and high-risk groups. Surgery alone of early stage primary tumours might be adequate when stromal FN is negative. Aggressive treatments should be considered when both TNC and FN are abundant.Peer reviewe

Modélisation numérique des mouvements de sol induits par des excavations

La modélisation numérique des mouvements de sol induits par des excavations soutenues reste un problème complexe où de multiples paramètres peuvent avoir une réelle influence sur le résultat final. Cet article propose dans un premier temps d’étudier l’influence de l’état initial des contraintes en modélisant le phasage de réalisation de différents panneaux d’une paroi moulée. Différents calculs, en deux et trois dimensions, intégrant ou pas ce phasage, sont réalisés afin de mettre en évidence les effets de l’état initial des contraintes sur les mécanismes de déformation induits par l’excavation. Au préalable, une étude précise des mouvements de sol générés lors de la réalisation des parois est réalisée pour identifier les variations de la contrainte horizontale en arrière de l’écran. Dans un second temps, une étude relative aux effets des non-linéarités élastiques dans les lois de comportement comprenant un critère de rupture de type Mohr-Coulomb est effectuée. Elle permet d’identifier les liens entre les paramètres des parties élastiques des lois de comportement et les mouvements calculés lors d’une excavation

Effect of a diesel engine ban on asthma-related morbidity in Beirut

Background: Diesel emissions contain smaller amounts of CO, CO2 and hydrocarbons than gasoline, but their content in nitrogen oxides and particulate matter is significantly higher. Some of this particulate matter is of the respirable size and penetrates deep into the tracheobronchial tree. Exposure to diesel emissions is associated with respiratory disease.In Lebanon, a rapid expansion in the transportation sector allowed a gradual introduction of diesel fuel-operated vehicles, which had been banned till 1977. Fuel was being imported with little control over its quality. A ban was imposed on light and medium-duty diesel engine on the Lebanese territory as of July 1, 2002.Objective: To determine the effect of the diesel ban on the air concentration of particulate matter and on asthma-related morbidity in children admitted to the emergency room (ER) of the American University of Beirut Medical Center (AUBMC).Methods: Air samples were collected at multiple large intersections of Beirut before and after the ban. Each sample was collected over a period of 30 minutes and analyzed for particulate matter. Air sampling was done during summer, at which time the concentration of particulate matter is at its peak. The average of all the concentrations was computed.The records of all visits to AUBMC-ER were reviewed over a two-year period: Period 1 (Pre-ban: July 1, 2001 to June 30, 2002) and Period 2 (Post-ban: July 1, 2002 to June 30, 2003). All patients 0-15 years of age presenting with acute asthma were identified.Results: The average concentration of particulate matter was 181.3 µg/m3 and 97.1 µg/m3 before and after the ban respectively. The total numbers of ER visits for pediatric patients were 6453 and 6865 in period 1 and period 2, respectively. Of those, 313 were due to asthma in period 1 and 223 in period 2. The number of asthma-related visits was significantly reduced during period 2. Asthma-related visits were significantly reduced during October, November and December of period 2 compared to the same months of period 1, while it was significantly increased during the month of June.Discussion: This study shows that a ban on diesel engine resulted in a decrease in the air concentration of particulate matter and was associated with a reduction in the number of emergency room visits for acute asthma. This reduction was most marked during the season of viral respiratory infections. We postulate that a reduction in the concentration of air pollutants was protective against viral-induced asthma exacerbations

Effect of a diesel engine ban on asthma-related morbidity in Beirut

Diesel engine exhaust emissions are a mixture of gases, vapors, liquid aerosols and particulate matter that are known to increase cardiorespiratory morbidity.On July 1, 2002, a ban was imposed on the use of diesel-operated vehicles on the Lebanese territory as a public health measure. The aim of this study is to determine the effect of this ban on the air concentration of particulate matter and on asthma-related morbidity in the Beirut area.Methods: Air sampling was done at multiple large intersections of Beirut before and after the ban using a portable high-volume air sampler equipped with glass fiber filters that capture particles of diameter greater than 0.01 microns. Each sample was collected over a period of 30 minutes. The filter was then weighed for particulate matter determination.The records of all visits to the Emergency Room (ER) of the American University of Beirut Medical Center, a major tertiary care center in Beirut, Lebanon were reviewed over a two-year period. The first year (July 1, 2001 to June 30, 2002 , period 1) preceded the ban while the second year (July 1, 2002 to June 30, 2003, period 2) followed it immediately. All patients 0-15 years of age presenting with acute asthma were identified. Results: The average concentration of particulate matter was 181.3 µg/m3 and 97.1 µg/m3 before and after the ban respectively.The total numbers of ER visits for pediatric patients were 6453 and 6865 in period 1 and period 2 respectively. Of those, 313 were due to asthma in period 1 and 223 in period 2. The number of asthma-related visits was significantly reduced during period 2. When we looked at the monthly distribution of visits, asthma-related visits were significantly reduced during October, November and December of period 2 compared to the same months of period 1, while it was significantly increased during the month of June. Discussion: This study shows that a ban on diesel engine resulted in a decrease in the air concentration of particulate matter and was associated with a reduction in the number of emergency room visits for acute asthma. This reduction was most marked during the season of viral respiratory infections. We postulate that a reduction in the concentration of air pollutants was protective against viral-induced asthma exacerbations.<br/

Hydraulic fracturing of rock-fill dam

The condition in which hydraulic fracturing in core of earth-rock fill dam maybe induced, the mechanism by which the reason of hydraulic fracturing canbe explained, and the failure criterion by which the occurrence of hydraulicfracturing can be determined, were investigated. The condition dependson material properties such as, cracks in the core and low permeability ofcore soil, and “water wedging” action in cracks. An unsaturated core soiland fast impounding are the prerequisites for the formation of “waterwedging” action. The mechanism of hydraulic fracturing can be explainedby fracture mechanics. The crack propagation induced by water pressuremay follow any of mode I, mode II and mixed mode I-II. Based on testingresults of a core soil, a new criterion for hydraulic fracturing was suggested,from which mechanisms of hydraulic fracturing in the core of rock-fill damwere discussed. The results indicated that factors such as angle betweencrack surface and direction of principal stress, local stress state at thecrack, and fracture toughness KIC of core soil may largely affect theinduction of hydraulic fracturing and the mode of the propagation of thecrack.The condition in which hydraulic fracturing in core of earth-rock fill dam maybe induced, the mechanism by which the reason of hydraulic fracturing canbe explained, and the failure criterion by which the occurrence of hydraulicfracturing can be determined, were investigated. The condition dependson material properties such as, cracks in the core and low permeability ofcore soil, and “water wedging” action in cracks. An unsaturated core soiland fast impounding are the prerequisites for the formation of “waterwedging” action. The mechanism of hydraulic fracturing can be explainedby fracture mechanics. The crack propagation induced by water pressuremay follow any of mode I, mode II and mixed mode I-II. Based on testingresults of a core soil, a new criterion for hydraulic fracturing was suggested,from which mechanisms of hydraulic fracturing in the core of rock-fill damwere discussed. The results indicated that factors such as angle betweencrack surface and direction of principal stress, local stress state at thecrack, and fracture toughness KIC of core soil may largely affect theinduction of hydraulic fracturing and the mode of the propagation of thecrack

Synthesis of a benchmark exercise for geotechnical analysis of a thermoactive pile

Thermoactive piles ensure a dual function: they support mechanically the superstructure and at the same time they are used as heat exchanger elements. In comparison to standard design practice, this requires considering the associated thermal loadings from the operation of the heat exchange system. To assess the thermal effects on the mechanical behaviour, different design assumptions and modelling approaches can be used. Therefore, within the framework of European Cooperation in Science and Technology Action TU1405 ‘Geothermal Applications for Buildings and Infrastructures’, benchmarking of a single geothermal pile has been performed. Hence, both heating and cooling of the pile were considered while different rigidities (representing the upper structure) on the pile head were assumed. The results show that a broad range of design assumptions could be used, which unfortunately lead to noticeable differences. Although the main focus was on the methods and assumptions employed, the exercise also opens questions about the influence of transient effects, thermal strains in the ground, temperature cycles and so on. Owing to the complexity of the topic, some of them were just mentioned, while others were addressed in greater detail. In general, the findings emphasise the need for further practice-oriented guidance to be presented in design guidelines and standards