Serum Neurotrophin Profile in Systemic Sclerosis

International audienceBACKGROUND: Neurotrophins (NTs) are able to activate lymphocytes and fibroblasts; they can modulate angiogenesis and sympathic vascular function. Thus, they can be implicated in the three pathogenic processes of systemic sclerosis (SSc). The aims of this study are to determine blood levels of Nerve Growth Factor (NGF), Brain-Derived Neurotrophic Factor (BDNF) and Neurotrophin-3 (NT-3) in SSc and to correlate them with clinical and biological data.METHODS: Serum samples were obtained from 55 SSc patients and 32 control subjects to measure NTs levels by ELISA and to determine their relationships with SSc profiles. FINDINGS: Serum NGF levels were higher in SSc patients (288.26 ± 170.34 pg/mL) than in control subjects (170.34 ± 50.8 pg/mL, p<0.001) and correlated with gammaglobulins levels and the presence of both anti-cardiolipin and anti-Scl-70 antibodies (p<0.05). In contrast, BDNF levels were lower in SSc patients than in controls (1121.9 ± 158.1 vs 1372.9 ± 190.9 pg/mL, p<0.0001), especially in pulmonary arterial hypertension and diffuse SSc as compared to limited forms (all p<0.05). NT-3 levels were similar in SSc and in the control group (2657.2 ± 2296 vs 2959.3 ± 2555 pg/mL, NS). BDNF levels correlated negatively with increased NGF levels in the SSc group (and not in controls). CONCLUSION: Low BDNF serum levels were not previously documented in SSc, particularly in the diffuse SSc subset and in patients with pulmonary hypertension or anti-Scl-70 antibodies. The negative correlation between NGF and BDNF levels observed in SSc and not in healthy controls could be implicated in sympathic vascular dysfunction in SSc

Hemócitos de Bradybaena similaris e Megalobulimus abbreviatus (Gastropoda, Stylommatophora)

Hemocytes act in the defense system against invading organisms, foreign particles aiding the recognition of what is own to the body of gastropods and what is not. Information and studies on the hemocytes in species of mollusks healthy (no infections), especially in Bradybaena similaris (Fèrussac, 1821) and Megalobulimus abbreviatus (Bequaert, 1948) are scarce. Therefore, this work aims at characterization and quantification of hemocytes present in the hemolymph of these two species. In this work three cell types were identified in the hemolymph of both species: round cells, hyalinocytes and granulocytes. The three types of hemocytes were measured, and the average of total diameter and the nucleus for each was calculated. On B. similaris, the average diameter of round cells was 10.7 μm, of hyalinocytes was 20 μm and of granulocytes was 25.4 μm. On M. abbreviatus, the average diameter of round cells was 11.7 μm, of hyalinocytes was 21.5 μm and of granulocytes was 30.5 μm. Although the hyalinocytes have similar averages between B. similaris and M. abbreviatus, the cells were demonstrated significant differences in their total diameter and size of the nucleus (p<0.0001). The average density of cells per ml without distinction of cellular type was 197,813 cells/ml for M. abbreviatus, and 416,333 cells/ml for B. similaris. The most frequent hemocytes in M. abbreviatus and B. similaris were hyalinocytes, unlike other gastropods.Os hemócitos atuam no sistema de defesa contra organismos invasores e partículas estranhas, auxiliando o reconhecimento do que é próprio do corpo dos grastrópodes e o que não é. São escassas as informações e estudos sobre os hemócitos em espécies de moluscos saudáveis (sem infecções), principalmente em Bradybaena similaris (Fèrussac, 1821) and Megalobulimus abbreviatus (Bequaert, 1948). Portanto, este trabalho tem como objetivos a caracterização e quantificação dos hemócitos presentes na hemolinfa destas duas espécies. Neste trabalho, foram identificados três tipos celulares na hemolinfa de ambas espécies: as células redondas, hialinócitos e granulócitos. Os três tipos de hemócitos foram medidos e foi calculada a média do diâmetro total e do núcleo para cada um deles. Para B. similaris, o diâmetro médio das células redondas foi de 10,7 μm, dos hialinócitos foi de 20 μm e dos granulócitos de 25,4 μm. Para M. abbreviatus, o diâmetro médio foi de 11,7 μm para as células redondas, de 21,5 μm para os hialinócitos e de 30,5 μm para os granulócitos. Embora os hialinócitos possuam médias parecidas entre B. similaris e M. abbreviatus, foram detectadas diferenças significativas do diâmetro celular total e diâmetro do núcleo (p<0,0001) dessas células entre as espécies estudadas. A densidade média de células por ml, sem distinção de tipo celular foi de 197.813 células/ml para M. abbreviatus, e de 416.333 células/ml para B. similaris. Diferentemente de outros gastrópodes, os hemócitos mais frequentes em M. abbreviatus e em B. similaris foram os hialinócitos

A Prospective International Study on Adherence to Treatment in 305 Patients With Flaring SLE: Assessment by Drug Levels and Self-Administered Questionnaires

Nonadherence to treatment is a major cause of lupus flares. Hydroxychloroquine (HCQ), a major medication in systemic lupus erythematosus, has a long half‐life and can be quantified by high‐performance liquid chromatography. This international study evaluated nonadherence in 305 lupus patients with flares using drug levels (HCQ <200 ng/ml or undetectable desethylchloroquine), and self‐administered questionnaires (MASRI <80%). Drug levels defined 18.4% of the patients as severely nonadherent. In multivariate analyses, younger age, nonuse of steroids, higher body mass index, and unemployment were associated with nonadherence by drug level. Questionnaires classified 23.4% of patients as nonadherent. Correlations between adherence measured by questionnaires, drug level, and physician assessment were moderate. Both methods probably measured two different patterns of nonadherence: self‐administered questionnaires mostly captured relatively infrequently missed tablets, while drug levels identified severe nonadherence (i.e., interruption or erratic tablet intake). The frequency with which physicians miss nonadherence, together with underreporting by patients, suggests that therapeutic drug monitoring is useful in this setting

Carathéodory, Helly and the others in the max-plus world

International audienceCarathéodory's, Helly's and Radon's theorems are three basic results in discrete geometry. Their max-plus or tropical analogues have been proved by various authors. We show that more advanced results in discrete geometry also have max-plus analogues, namely, the colorful Carathéodory theorem and the Tverberg theorem. A conjecture connected to the Tverberg theorem-Sierksma's conjecture-although still open for the usual convexity, is shown to be true in the max-plus setting. © 2009 Springer Science+Business Media, LLC