Temporal Dynamics and Impact of Climate Factors on the Incidence of Zoonotic Cutaneous Leishmaniasis in Central Tunisia

Old world cutaneous leishmaniasis is a vector-borne disease occurring in rural areas of developing countries. The main reservoirs are the rodents Psammomys obesus and Meriones shawi. Zoonotic Leishmania transmission cycle is maintained in the burrows of rodents where the sand fly Phlebotomus papatasi finds the ideal environment and source of blood meals. In the present study we showed seasonality of the incidence of disease during the same cycle with an inter-epidemic period ranging from 4 to 7 years. We evaluated the impact of climate variables (rainfall, humidity and temperature) on the incidence of zoonotic cutaneous leishmaniais in central Tunisia. We confirmed that the risk of disease is mainly influenced by the humidity related to the months of July to September during the same season and mean rainfall lagged by 12 to 14 months

Water balance of the olive tree-annual crop association : a modeling approach

Water transfers within mixed crops systems are complicated to understand due to the large number of complex interactions between the various components. Standard techniques fail to provide the proper assessment of the components of the water balance. Experiments and modeling developments are used to understand the dynamics of water transfers within the association of olive trees with annual crops under irrigation in Central Tunisia. The whole system is represented by a unit area made up of three components: a plot with the annual crop, a plot with the olive tree and a plot of bare soil. The modeling approach is based on the concept of reservoir. The model works on a daily time step and accounts for the lateral transfers of water occurring between the components of the system: (i) the water uptake by the roots of olive trees; (ii) the physical flow of water between the irrigated plot and the non-irrigated ones. A field experiment was carried out during 2 years (2002, 2003) and three crop cycles (spring potato, spring pea and autumn potato) in order to calibrate the model and test its validity. olive tree transpiration was estimated from sap flow measurements and soil moisture in the different compartments was measured by neutron probe technique. The experimental data compare fairly well with the model outputs. The first purpose of the model is to understand the functioning of the olive tree-annual crop association from a water standpoint, but it can be easily extended to other intercropping systems mixing perennial vegetation with annual crops or used as a management tool. The estimates of the water extracted by the olive trees in each reservoir appear to be much more significant than those of the water physically transferred between reservoirs

Trace metal accumulation in the commercial mussel M. galloprovincialis under future climate change scenarios

11 pages, 3 figures, 3 tablesThe current trend of climatic alterations will accelerate the modification of the ocean system by, among other aspects, changing the metal speciation and its bioavailability which may have an impact in their accumulation by marine organisms. Understanding the impact of these potential changes is essential for future risk assessment of metal contamination. In the present study, we selected the species Mediterranean mussel (Mytilus galloprovincialis) as the main European aquaculture production bivalve and due to its widespread use for biomonitoring purposes. A long-term test (2 months) was carried out to explore the impact that global change in the marine environment (warming and CO2 increase) may exert on the accumulation of dissolved trace metals (Cu, Co, Pb, Cd, Cr, As and Ni) in different body parts of mussels (foot and rest of soft tissues). Studied mussels were collected at two different climatic locations (Atlantic and Mediterranean Sea) and exposed to unspiked, unpolluted seawater from the Vigo Ria (NW Iberian Peninsula). Results showed that under the global change conditions proposed in this study (1100 pCO2 and 25 °C), the increase in temperature resulted in a lower condition index and byssus strength for mussels from Atlantic Sea, while Mediterranean sea mussels, adapted to higher temperatures, did not show remarkable variations. According to trace metals accumulation in different body parts of the studied mussels, it was observed that the effect of increasing CO2 alone did not show to have an impact in the bioaccumulation, but the combined stressors (increase in CO2 and temperature) may lead to an increase in the bioaccumulation for some elements. The increase in temperature resulted in a decrease of the Cu content of foot tissue (byssus gland) in mussels from Atlantic Sea, which is in accordance with the lower byssus strength observed under such conditions. Our results indicate that the expected seawater temperature increase, which will be produced gradually during next decades, should be further study to ensure the species adaptability and aquaculture productionAuthors wish to acknowledge funding provided by Spanish government through the Ministerio de Economía y Competitividad (project ARIOS Ref. CTM2016-76146-C3-2- R/ CTM2016-76146-C3-1-R) and the post-doctoral position of A. Romero-Freire funded by the Ministry of Science, Innovation and Universities (FJCI-2016-28622).Peer reviewe

Les cancers rares du larynx : a propos de 20 cas

Introduction : Les cancers rares du larynx sont définis comme étant des entités d’histopathologie inhabituelle au niveau laryngé. Ils ont été rapportés dans la littérature mondiale sous forme de cas isolés ou de séries de quelques cas. Le but de ce travail est de présenter la démarche diagnostique et la prise en charge de ces types de tumeurs à l’institut Salah Azaiez de Tunis.Patients et méthodes : Etude rétrospective portant sur 20 cas de cancers laryngés primitifs autre que le carcinome épidermoide sur la période 1989-2009.Résultats : L’âge moyen était de 59,35 ans. Le sexe ratio était de 3/1. La dysphonie était le motif de consultation dans 95% des cas. La mobilité laryngée était conservée dans 50% des cas. L’examen anatomopathologique avait conclu à un carcinosarcome dans 25% des cas, un carcinome type-glandes salivaires dans 20% des cas, une tumeur neuro-endocrine dans 10% des cas, un sarcome dans 25% des cas et un lymphome dans 20% des cas. Le traitement était chirurgical dans 14 cas, par radiothérapie exclusive dans 2 cas, radio et chimiothérapie dans 2 cas et chimiothérapie seule dans 2 cas. Le pronostic était bon avec une survie globale de 80%.Conclusion : Seul l’examen anatomopathologique précis et la bonne connaissance du cours évolutif des cancers rares du larynx sont les seuls garants d’une thérapeutique adaptée à chaque type.Mots clés : Larynx - Histologie - Sarcome – Lymphome - Cylindrome - Adénocarcinome-Diagnostic -ThérapeutiqueObjective: Rare cancers of the larynx are defined as unusual laryngeal histologicalentities. They have been reported in the world literature as isolated cases or series of a few cases.The aim of this work is to present our experience in this type of tumors.Patients and methods: A retrospective study of 20 cases of primitive laryngeal cancers other than squamous cell carcinoma of the period 1989-2009.Results: Mean age was 59,35 years. Sex ratio was 3/1. Dysphony an was there a son for consultation in 95% of cases. Laryngeal mobility was preserved in 50% of cases. The histopathological examination concluded a carcinosarcoma in 25% of cases, carcinoma- type salivary glands in 20% of cases, aneuroendocrinetumorin 10% of cases, sarcoma in 25% of cases and lymphoma in 20%. The treatment was surgical in 14cases, exclusive radiotherapy in 2 cases, radio and chemotherapy in 2 cases and chemotherapy alone in 2 cases. Overall survival was 80%.Conclusion: Only the accurate histology and good knowledge of the evolutive patterns of rare cancers of the larynx are the only guarantors of adapted therapeutic to each type.Keywords: Larynx-Histology -Sarcoma -Lymphoma -Cylindroma-Adenocarcinoma-Diagnosis - Therap

Behavioural and eco-physiological responses of the mussel Mytilus galloprovincialis to acidification and distinct feeding regimes

The carbon dioxide taken up by the ocean is increasing as levels of atmospheric carbon dioxide increase, thus lowering the ocean pH and altering the carbonate system. In this laboratory study, we evaluated the physiological responses of juvenile mussels Mytilus galloprovincialis from Galician waters (NW Iberian Peninsula) exposed to control (500 µatm) and elevated (800 or 1200 µatm) seawater pCO2 conditions under 2 different feeding regimes (optimal and suboptimal). Shell properties such as compressive strength and composition (organic matter and aragonite:calcite ratio) were negatively affected by high seawater pCO2, regardless of food availability. This result suggests that water chemistry is a main driver for shell development. Under the optimal feeding regime, mussel feeding rates increased in response to elevated pCO2, presumably as a strategy to maintain a high strength of attachment. In contrast, mussels on the suboptimal diet showed weak attachment and narrow valve opening at the highest pCO2 condition. Thus, our results suggest that with optimal food availability, mussels were resilient to water acidification with respect to feeding activity, valve opening and attachment strength. Under a suboptimal diet, however, the ability of mussels to respond to acidification was compromised. These results highlight complex ecophysiological interactions for calcifying organisms subjected to climate changeThis study was funded by the Spanish government through the Ministerio de Economía y Competitividad that included European FEDER funds (projects Ref. AGL-2013-45945-R, CTM2016-76146-C3-2-R/ CTM2016- 76146-C3-1-R). J.L. acknowledges funding from the Spanish National Research Council (CSIC) through the Program ICOOP+ 2016 (Ref. ICOOPA20147)Peer reviewe

The Mediterranean mussel Mytilus galloprovincialis: responses to climate change scenarios as a function of the original habitat

16 pages, 4 figures, 2 tables.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution LicenseThe impact of simulated seawater acidification and warming conditions on specimens of the mussel Mytilus galloprovincialis locally adapted to very distinct, widely separated sites in the Mediterranean Sea (Tunisia) and Atlantic Sea (Galicia, NW Spain) was evaluated in relation to key behavioural and eco-physiological parameters. Over the 2-month exposure to the experimental conditions, mussels were fed optimally to ensure that there are no synergistic interactions between climate change drivers and energetic status of the individuals. In general, regardless of origin (Atlantic or Mediterranean), the mussels were rather resilient to acidification for most of the parameters considered and they were able to grow in strongly acidified seawater through an increased feeding activity. However, shell strength decreased (40%) consistently in both mussel populations held in moderately and highly acidified seawater. The observed reduction in shell strength was not explained by slight alterations in organic matter, shell thickness or aragonite:calcite ratio. The combined effects of high acidification and warming on the key response of byssus strength caused a strong decline in mussel performance, although only in Galician mussels, in which the valve opening time decreased sharply as well as condition index (soft tissue state) and shell growth. By contrast, the observed negative effect of highly acidified scenario on the strength of Tunisian mussel shells was (partly but not totally) counterbalanced by the higher seawater temperature. Eco-physiological and behavioural interactions in mussels in relation to climate change are complex, and future scenarios for the ecology of the species and also the feasibility of cultivating them in Atlantic and Mediterranean zones are discussedThis work was supported by the Spanish government through the Ministerio de Economía y Competitividad and European FEDER funds (AGL-2013-45945-R, CTM2016-76146-C3-2-R/CTM2016-76146-C3-1-R) and the Spanish National Research Council (CSIC) through the program I-COOP+ 2016 (ICOOPA20147 to J.L.)Peer reviewe

Seawater carbonate chemistry and shell properties, behaviour of the mussel Mytilus galloprovincialis

The carbon dioxide taken up by the ocean is increasing as levels of atmospheric carbon dioxide increase, thus lowering the ocean pH and altering the carbonate system. In this laboratory study, we evaluated the physiological responses of juvenile mussels Mytilus galloprovincialis from Galician waters (NW Iberian Peninsula) exposed to control (500 µatm) and elevated (800 or 1200 µatm) seawater pCO2 conditions under 2 different feeding regimes (optimal and suboptimal). Shell properties such as compressive strength and composition (organic matter and aragonite:calcite ratio) were negatively affected by high seawater pCO2, regardless of food availability. This result suggests that water chemistry is a main driver for shell development. Under the optimal feeding regime, mussel feeding rates increased in response to elevated pCO2, presumably as a strategy to maintain a high strength of attachment. In contrast, mussels on the suboptimal diet showed weak attachment and narrow valve opening at the highest pCO2 condition. Thus, our results suggest that with optimal food availability, mussels were resilient to water acidification with respect to feeding activity, valve opening and attachment strength. Under a suboptimal diet, however, the ability of mussels to respond to acidification was compromised. These results highlight complex ecophysiological interactions for calcifying organisms subjected to climate change