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A new and original gas sensor-system dedicated to the selective monitoring of nitrogen dioxide in air and in the presence of ozone, has been successfully achieved. Because of its high sensitivity and its partial selectivity towards oxidizing pollutants (nitrogen dioxide and ozone), copper phthalocyanine-based chemoresistors are relevant. The selectivity towards nitrogen dioxide results from the implementation of a high efficient and selective ozone filter upstream the sensing device. Thus, a powdered indigo/nanocarbons hybrid material has been developed and investigated for such an application. If nanocarbonaceous material acts as a highly permeable matrix with a high specific surface area, immobilized indigo nanoparticles are involved into an ozonolysis reaction with ozone leading to the selective removal of this analytes from air sample. The filtering yields towards each gas have been experimentally quantified and establish the complete removal of ozone while having the concentration of nitrogen dioxide unchanged. Long-term gas exposures reveal the higher durability of hybrid material as compared to nanocarbons and indigo separately. Synthesis, characterizations by many complementary techniques and tests of hybrid filters are detailed. Results on sensor-system including CuPc-based chemoresistors and indigo/carbon nanotubes hybrid material as in-line filter are illustrated. Sensing performances will be especially discussed.

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PURPOSE: To compare the effects of benzalkonium chloride (BAC)-preserved and unpreserved antiallergic eye drops on the human 3D-reconstituted corneal epithelial model (3D-HCE). METHODS: 3D-HCE were treated for 24 h followed or not by a 24 h post-incubation recovery period (24 h+24 h) with phosphate-buffered saline (PBS), 0.01% BAC, unpreserved formulations of ketotifen, N Acetyl-Aspartyl Glutamic Acid (NAAGA), cromoglycate, or BAC-preserved commercial formulations of ketotifen, olopatadine, epinastine, and levocabastine. The 3D-HCE viability was evaluated using the 3-(4,5-Dimethylthiazol-2-yl) -2,5-Diphenyltetrazolium Bromide (MTT) test at 24 h and 24 h+24 h. At 24 h, the numbers of Cluster of Differentiation 54 (CD54)- and Ki67-immunopositive cells as well as the number of apoptotic deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells were evaluated on 3D-HCE frozen sections. The expression of the tight junction-associated protein occludin was also assessed using fluorescence confocal microscopy on flat-mounted 3D-HCE epithelia. RESULTS: The MTT and the TUNEL tests revealed a significant decrease of cell viability and an increased apoptosis in the superficial layers of the 3D-HCE only when treated with BAC-containing formulations and in a BAC concentration-dependent manner. The expression of CD54 and Ki67 in the basal layers was also increased in this group. A concentration-dependent disorganization of occludin distribution in the epithelium treated with BAC-containing solutions was also observed. The unpreserved formulations induced effects comparable to the control. CONCLUSIONS: BAC-preserved solutions decreased cell viability and induced apoptosis in a concentration-dependent manner. Moreover, they induced CD54 expression, proliferation in the basal layers, and changes in the distribution of occludin, which is consistent with a disorganization of the tight-junctions and suggests the loss of the epithelial barrier function. On the contrary, the unpreserved solutions did not impair cell structures and viability, suggesting a better tolerance for the ocular surface. As allergic patients often exhibit impaired and inflammatory ocular surface, BAC-free compounds should be the first choice when treating allergic conjunctivitis.

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There is a severe shortage of knowledge of bee biogeography. Some former studies have highlighted a link between bee diversity and xeric ecosystems, but we know practically nothing of the macro-ecological factors driving bee diversity. The present study aims to analyse the main macro-ecological factors driving bee species-richness in the Saharan region. Our dataset includes 25,000+ records for localities in Africa, between 37 degrees and 10 degrees N. Maps and GIS were used to get a first overview of the distribution of the studied taxa. Partial least squares analysis (PLS) was used to study the impact of a set of ecological factors on the bee species richness (SR). The mapping highlighted the clustering of the highest bee SR values in some parts of the Saharan area (e.g. Maghreb, western Africa). In Central Sahara, there is an obvious topological coincidence of the high SR, the local mountain chains and the inland waters. The PLS helped to quantify the relationships between bee SR and a set of eco-climatic variables. It also highlighted a residual variance not explained by the considered descriptors. Our results recover the tight link between bee SR and xeric ecosystems. They also suggest that, within these ecosystems, bee SR is driven by an optimum of the energy-water balance (on which adjustment is allowed by the above gradients).

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AIM: To compare the conjunctival and corneal reactions of commercially available solution of latanoprost (Xalatan) and preservative-free (PF) tafluprost in rabbits. METHODS: The rabbits received 50 microl of phosphate-buffered saline (PBS), PF-tafluprost 0.0015%, latanoprost 0.005% or benzalkonium chloride (BAK) 0.02%; all solutions were applied at 5 min intervals for a total of 15 times. The ocular surface toxicity was investigated using slit-lamp biomicroscopy examination, flow cytometry (FCM) and on imprints for CD45 and tumour necrosis factor-receptor 1 (TNFR1) conjunctival impression cytology (CIC) and corneal in vivo confocal microscopy (IVCM). Standard immunohistology also assessed inflammatory/apoptotic cells. RESULTS: Clinical observation and IVCM images showed the highest ocular surface toxicity with latanoprost and BAK, while PF-tafluprost and PBS eyes presented almost normal corneoconjunctival aspects. FCM showed a higher expression of CD45+ and TNFR1+ in latanoprost- or BAK-instilled groups, compared with PF-tafluprost and PBS groups. Latanoprost induced fewer positive cells for inflammatory marker expressions in CIC specimens compared with BAK-alone, both of which were higher than with PF-tafluprost or PBS. Immunohistology showed the same tendency of toxic ranking. CONCLUSION: The authors confirm that rabbit corneoconjunctival surfaces presented a better tolerance when treated with PF-tafluprost compared with commercially available latanoprost or BAK solution.

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Opisthorchiid eggs were found in 6 out of 27 (22%) huskies while an ELISA detected antibodies against Opisthorchis felineus and Metorchis bilis in 24 (89%) and 25 (93%) sera taken from these dogs, respectively. All dogs showed an increased activity of glutamate dehydrogenase while aspartate aminotransferase was normal in all samples. Ten weeks after treatment with praziquantel no fluke eggs were found in the faeces from any animal and antibody titres dropped in all animals.

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BACKGROUND: The implantable cardioverter/defibrillator (ICD) has been shown to be superior to antiarrhythmic drug therapy for the secondary prevention of sudden cardiac death. Its role in the primary prevention of sudden death after myocardial infarction is unknown. Methods and Results The Defibrillator in Acute Myocardial Infarction Trial (DINAMIT) is a randomized, open-label, parallel-group comparison of ICD therapy versus no ICD therapy in selected survivors of acute myocardial infarction. It will test the hypothesis that reduction of sudden arrhythmogenic death by means of the ICD will result in reduction of overall mortality rates in patients at high risk after acute myocardial infarction. Accordingly, this international multicenter study aims to enroll patients shortly after their infarction (day 6 to day 40) who have reduced left ventricular function (left ventricular ejection fraction

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Normal (non-transformed) human mammary epithelial cell lines derived from reduction mammoplasties were analyzed by immunocytochemistry with more than 80 monoclonal antibodies (mAbs) and other specific reagents to tissue-specific and developmentally regulated antigens at different passage levels. A subpopulation of poorly differentiated, proliferating epithelial cells, corresponding to the 'selected' cell type of late passages, is shown to be characterized by a new marker, the histo-blood group antigen H type 2, probably carried on a membrane-bound glycolipid. These cells also express a number of other onco-developmental carbohydrate antigens [Le(y), Le(x), sialosyl-Le(a), precursor of Thomsen Friedenreich antigen (Tn), but not Thomsen-Friedenreich antigen and sialosyl-Tn]. Their cytokeratin (CK) phenotype, as assessed by reactivity with monospecific mAbs and two-dimensional gel electrophoresis, is CK 5, 6, 14 and 17, with CK 19 being consistently absent, and varying minor amounts of CK 7, 8 and 18, as well as 15 and 16. The reactivity of these cells with a panel of 11 mAbs specific for CK 18 varies considerably even after cloning, indicating heterogeneity of epitope expression or accessibility. Our data strongly suggest that the H type 2+ cells develop from the basal cell layer of the mammary gland.

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We have examined the expression of 7 well defined tumor markers/tumor associated antigens (H type 2, X, Y, sialyl-Lea, CEA, MAM-6, and Tn) and a tumor associated antigen defined by a new own monoclonal antibody on non-transformed human epithelial cell lines derived from reduction mammoplasties by means of immunocytochemistry with monoclonal antibodies. Two cell types are discernible: slowly or non-proliferating, lumenal derived (I), and proliferating, stem cell-like, basal cell-derived cells (II). Five out of the 8 tumor markers were expressed on type I cells, and all 8 on type II cells. The number of positive cells varied considerably from a few to 100 per cent depending on the individual markers. The observed patterns proved to be characteristic and reproducible; they appear to reflect the developmental stage of the cells cultured in vitro rather than a direct influence of the culture conditions.

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The success of cultivation of epithelial cells from normal, neoplastic and preneoplastic tissues is reviewed. MCDB 170 medium with special supplements is useful for epithelial cell culture. The epithelial character was demonstrated by the reaction with 3 different monoclonal antibodies. Most cell populations from preneoplastic and neoplastic tissues were identified as fibroblasts. Cell proliferation as measured by cell doubling time, labeling index, flow cytometry did not differ between the tissue types examined. Only 3H-thymidine uptake showed an increased tendency in cells from preneoplastic and neoplastic tissues. The use of normal human breast epithelial cells for molecular biological studies is recommended.

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This study is based on 48 cases of paralysis of the femoral or sciatic nerves complicating hip surgery, mostly total hip arthroplasty. Most of these lesions arose during difficult operations. The diagnosis was clinical and electromyographic, but it was not always made from the outset. The prognosis was better for the cases of paralysis of the femoral or peroneal nerves than for the cases of generalised sciatic paralysis in which the recovery, slower as it was, was only satisfactory in 15 cases out of 26. The treatment was primarily medical and required reeducation. A surgical treatment was considered when the electrical exploration showed no improvement after 6 weeks.

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In this paper we present a simple colorimetric method for evaluating cell growth in adhering cell cultures. This technique is based on the staining of basophilic cellular compounds (mainly nucleic acids) with methylene blue. To check its reliability, we have compared the quantity of dye fixed by the cells with the number of cells released from the culture substratum by trypsinization, and with the total cellular protein content determined by the Lowry's method. In these experiments we have used human skin fibroblasts and human epithelial cells derived from the epithelium of the full-term umbilical cord. Like other alternative methods, the methylene blue colorimetric technique can be used in 96-well microplates and allows the rapid collection of large amounts of data. As an illustration, we report on the selection of optimal composition of culture medium for human skin fibroblasts.

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