Bikunin and α1-microglobulin in human zona pellucida and connective tissue

The occurrence of bikunin and ·₁-microglobuli n was investigated in human ovary and Fallopian tubes. Bikunin and ·₁-microglobulin are transcribed in the liver from a common gene. Bikunin immunoreactivity was detected in the zona pellucida. A positive reaction for bikunin was also observed in connective tissue of the oviduct. In addition, mast cells showed a more intense posi tive reaction than the surrounding connective tissue. Specific displaceable ·₁-microglobulin immunoreactivity was revealed in the zona pellucida. The data suggest that bikunin and ·₁- microglobulin are trapped in the zona pellucida. This revised version was published online in November 2006 with corrections to the Cover Date.     

Isolement et sélection de souches d'actinomycètes productrices de substances antifongiques de structure non-polyénique

Résumé Dans le but d'étudier des souches d'actinomycètes productrices de substances antifongiques de structure non-polyénique, 13, échantillons de sol prélevés dans le sud de la France ont été examinés. L'utilisation de milieux sélectifs a permis d'isoler 486 souches d'actinomycètes qui ont été testées vis-à-vis de quatre espèces de champignons et de levures: 18% des souches isolées sont actives sur au moins l'une des espèces utilisées. Parmi celles-ci 14 souches, productrices de substances de structure non-polyénique, ont été sélectionnées après étude des spectres d'absorption en UV des surnageants de culture, des extraits butanoliques de ces surnageants ou des extraits méthanoliques de mycélium. L'utilisation d'un test bactérien de toxicité à court terme (SOS Chromotest) a permis de montrer que 10 souches sur 14 présentent aussi une activité génotoxique.

---

Summary In order to study actinomycete strains producing non-polyenic antifungal substances 13 soil samples were collected in S. France. By using selective media 486 strains of actinomycetes were isolated and tested on four species of moulds and yeasts: 18% of the isolated strains were active against one or more of the test organisms. From these isolates 14 producers of non-polyenic antifungal substances were selected by means of u.v. absorption spectra of culture supernatant fractions, butanol extracts of these fractions, or methanol extracts of mycelium. A rapid bacterial toxicity assay (SOS Chromotest) demonstrated that 10 of the 14 selected strains had genotoxic activity.

---

Resumen Para el estudio de cepas de actinomicetes productores de sustancias antifúngicas no poliénicas, se recogieron 13 muestras de suelo en el S. de Francia. Utilizando medios selectivos se aislaron 486 cepas de actinomicetes que se ensayaron frente a cuatro especies de mohos y levaduras: 18% de las cepas aisladas mostraron actividad frente a uno o más de los organismos utilizados en el test. De estas cepas se seleccionaron 14 que eran productoras de sustancias antifúngicas no poliénicas mediante el espectro de absorción al U.V. de las fracciones sobrenadantes del cultivo, de extractos butanólicos de dichas fracciones o de extractos metanólicos del micelio. Un ensayo rápido de toxicidad bacteriana (SOS Chromotest) mostró que de las 14 cepas seleccionadas lo tenían actividad genotóxica.

     

Adsorption of phage λ to Salmonella typhimurium lamB + requires the presence of lipopolysaccharide in the outer membrane

Summary Two S. typhimurium strains TA1534 (rfa ⁺) and TA1538 (rfaE) were transformed with the lamB expression plasmid pAMH70. Transposition events with placMu55 hybrid phage were successful only with TA1534/pAMH70 strain. Using SDS-PAGE, the LamB protein was present in the total cell proteins but not in the outer membrane proteins of the TA1538/pAMH70 strain. The LamB protein must linked to the LPS of the outer membrane to allow adsorption of phage in S. typhimurium.     

Identification of Dirofilaria immitis-infected dogs with a coagglutination assay.

The presence of Dirofilaria immitis excretory-secretory (ES) products was detected in the urine of infected dogs using a coagglutination assay. Urine samples from 30 naturally infected dogs were positive. Seventeen of them were microfilaremic, whereas 13 had become amicrofilaremic after receiving 2 courses of diethylcarbamazine. Urine samples from 20 dogs infected with other parasites, Dipetalonema reconditum (7), Toxocara canis (5), and Ancylostoma caninum (8), and urine samples from 20 healthy dogs were negative. The assay detected 200 ng/ml or more of ES products. This assay is simple, easy to perform with minimum training, and requires no equipment. Therefore it should be useful to detect canine filariasis under field conditions.     

Influence of pulsatility on the development of intracardiac jets: an in vitro laser Doppler study.

So far, it has been hypothesized that numerical data obtained in steady flow conditions apply to pulsatile flows. In order to study the modifications of the velocity fields due to pulsatility, jets were produced by 8 orifices (with a diameter "D" of 4.4 to 11.3 mm) included in a chamber of 50 mm. The velocity was measured using laser Doppler anemometry with a pulsatile flow ("pf") and compared to the values obtained in steady ("sf"): at maximum velocity, the longitudinal velocity profile is qualitatively similar to this observed in steady flow: it is made of a plateau followed by an hyperbolic velocity decay in the turbulent area. The length of the core ("Lpf") is strongly related to "D" (Lpf = 3.72 D + 5.49, r = .99) and the velocity decay depends on the ratio between the distance "x" from the orifice and "D" (V/Vo = 2.83D/x + 3.46, r = .85, where V is the velocity at "x" and Vo the initial velocity). During the acceleration and the deceleration, the laminar core is disturbed by turbulences. The comparison of "pf" data with "sf" data demonstrated similar diameters at the origin of the jets (Dpf = 0.96 Dsf + .12, r = .99), but significant (p less than .0001) differences both for "L" and "V/Vo": Lpf = .91Lsf + 6.58, r = .97, V/Vopf = .63 V/Vosf + .34, r = .76. Thus, pulsatility modifies velocity fields and the results obtained in steady flow conditions do not apply to pulsatile jets.     

Angiovision: Aortic stent-graft placement by augmented angionavigation

The endovascular treatment of abdominal aortic aneurysm (EVAR - EndoVascular Aneurism Repair) has become an alternative therapy to conventional open surgery. The objective of Angiovision project was to contribute to the improvement of EVAR procedures in terms of accuracy and customization of the interventional strategy. Our approach was mainly based on the use of patient-specific data, computer-aided endovascular navigation and numerical simulation. We proposed a new FEM-based patient-specific simulation solution to estimate the deformations caused by the introduction of stiff endovascular devices. We developed and implemented an original endovascular navigation system to augment the intraoperative fluoroscopy with the visualization of deformed preoperative aorto-iliac structure, and related information concerning vessel wall (calcifications), as well as stent-graft virtual deployment. The proposed solution, that requires only lightweight computer equipment, can be used in a standard operating room in order to optimize device placement (from a single angle of incidence). Evaluation is currently under way.     

Differential signalling of NH2-terminal flag-labelled thrombopoietin receptor activated by TPO or anti-FLAG antibodies

In this report, we compared activation of NH2-terminal FLAG-labelled thrombopoietin receptor (Mpl) by anti-FLAG antibodies and by thrombopoietin (TPO). We found that anti-FLAG monoclonal antibodies M1 dimerize FLAG-labelled receptor and trigger proliferation of BaF3/FLAG-Mpl cells. In UT7/FLAG-Mpl cells, activation of the FLAG-Mpl receptor by low TPO concentrations triggered proliferation, while high concentrations triggered differentiation. Activation of FLAG-Mpl receptors in these cells by all tested concentrations of M1 antibodies induced proliferation but not differentiation. Low TPO concentrations induced similar to M1 antibodies level of Jak2, Stat3, Stat5 and Akt phosphorylation. In contrast, only TPO and not M1 antibodies activated Erks phosphorylation. Since the anti-FLAG antibodies do not react with the TPO binding site of the receptor, we hypothesize that they can trigger a distinct signal by dimerizing Mpl in a manner different from that induced by TPO.     

A simple and convenient microtiter plate assay for the detection of bactericidal antibodies to Vibrio cholerae O1 and Vibrio cholerae O139

It is believed that the correlate of protection for cholera can be determined by the serum vibriocidal assay. The currently available vibriocidal assays, based on the conventional agar plating technique, are labor intensive. We developed a simple and convenient microtiter plate assay for the detection of vibriocidal antibodies that is equally as efficient for Vibrio cholerae O1 and for V. cholerae O139. The addition of succinate and neotetrazolium made it possible to measure the growth of surviving bacterial target cells by monitoring a color change. We evaluated assay parameters (target strains, growth of target cells, complement source and concentration) that may affect the reproducibility of the method for V. cholerae O139. The results obtained with the microtiter plate assay were uniformly similar to those obtained with the conventional agar plating assay, when testing both the Inaba and Ogawa serotypes of V. cholerae O1. The microtiter plate assay was also convenient for measuring the activity of animal sera and mouse monoclonal antibodies.     

Synthesis and in vitro antiplasmodial evaluation of 4-anilino-2-trichloromethylquinazolines

To identify a new safe antiplasmodial molecular scaffold, an original series of 2-trichloromethylquinazolines, functionalized in position 4 by an alkyl- or arylamino substituent, was synthesized from 4-chloro-2-trichloromethylquinazoline 1, via a cheap, fast and efficient solvent-free operating procedure. Among the 40 molecules prepared, several exhibit a good profile with both a significant antiplasmodial activity on the W2 Plasmodium falciparum strain (IC₅₀ values: 0.4–2.2 μM) and a promising toxicological behavior regarding human cells (HepG2/W2 selectivity indexes: 40–83), compared to the antimalarial drug compounds chloroquine and doxycycline. The in vitro antitoxoplasmic and antileishmanial evaluations were conducted in parallel on the most active molecules, showing that these ones specifically display antiplasmodial properties.     

Space exploration by dendritic cells requires maintenance of myosin II activity by IP3 receptor 1

Dendritic cells (DCs) patrol the interstitial space of peripheral tissues. The mechanisms that regulate their migration in such constrained environment remain unknown. We here investigated the role of calcium in immature DCs migrating in confinement. We found that they displayed calcium oscillations that were independent of extracellular calcium and more frequently observed in DCs undergoing strong speed fluctuations. In these cells, calcium spikes were associated with fast motility phases. IP₃ receptors (IP₃Rs) channels, which allow calcium release from the endoplasmic reticulum, were identified as required for immature DCs to migrate at fast speed. The IP₃R1 isoform was further shown to specifically regulate the locomotion persistence of immature DCs, that is, their capacity to maintain directional migration. This function of IP₃R1 results from its ability to control the phosphorylation levels of myosin II regulatory light chain (MLC) and the back/front polarization of the motor protein. We propose that by upholding myosin II activity, constitutive calcium release from the ER through IP₃R1 maintains DC polarity during migration in confinement, facilitating the exploration of their environment.