[A randomized study of subconjonctival bevacizumab (Avastin®) injection for corneal neovascularization]

PURPOSE

The goal of this phase III, comparative, multicentric, randomized, double-blinded clinical trial was to investigate the superiority of subconjunctival bevacizumab injections versus placebo in the treatment of corneal neovascularization.

PATIENTS AND METHODS

We included 38 eyes (38 patients) with corneal neovascularization. Twenty patients received bevacizumab and 18 placebos. Patients received 3 monthly injections of either 5mg (0.2mL) bevacizumab or placebo. The main criteria of success was reduction of the surface area of corneal neovascularization after 3months (M3) versus baseline, as measured using semi-automatic analysis of color photographs.

RESULTS

The percentage of neovascularized corneal surface decreased by -8.6%±32.8 with bevacizumab, versus -2.6%±20.8 with placebo (p=0.5284). Four patients were determined to be responders (reduction of more than 30%), 3 in the bevacizumab group and 1 in the placebo group, all with neovascularization of less than 1year duration. When restricting the analysis to neovascularization of less than 1 year duration, the difference approached the threshold for significance (-31.8%±42.4 in the bevacizumab group and -0.9%±23.1 in the placebo group) (p=0.0637), as well as the number of responders (3/6 in the bevacizumab group versus 1/10 in the placebo group) (p=0.1181). No serious adverse event was reported.

CONCLUSION

This study shows the efficacy of subconjunctival bevacizumab injection in the reduction of neovascularized corneal surface area versus placebo, but only when the neovascularization has been present less than 1year. Nevertheless, the study did not attain the statistical power to pass the threshold of significance.

StREM1.3 REMORIN Protein Plays an Agonistic Role in Potyvirus Cell-to-Cell Movement in N. benthamiana

REMORIN proteins belong to a plant-specific multigene family that localise in plasma membrane nanodomains and in plasmodesmata. We previously showed that in Nicotiana benthamiana, group 1 StREM1.3 limits the cell-to-cell spread of a potexvirus without affecting viral replication. This prompted us to check whether an effect on viral propagation could apply to potyvirus species Turnip mosaic virus (TuMV) and Potato virus A (PVA). Our results show that StREM1.3 transient or stable overexpression in transgenic lines increases potyvirus propagation, while it is slowed down in transgenic lines underexpressing endogenous NbREMs, without affecting viral replication. TuMV and PVA infection do not alter the membranous localisation of StREM1.3. Furthermore, StREM1.3-membrane anchoring is necessary for its agonist effect on potyvirus propagation. StREM1.3 phosphocode seems to lead to distinct plant responses against potexvirus and potyvirus. We also showed that StREM1.3 interacts in yeast and in planta with the key potyviral movement protein CI (cylindrical inclusion) at the level of the plasma membrane but only partially at plasmodesmata pit fields. TuMV infection also counteracts StREM1.3-induced plasmodesmata callose accumulation at plasmodesmata. Altogether, these results showed that StREM1.3 plays an agonistic role in potyvirus cell-to-cell movement in N. benthamiana.

Multiple C2 domains and transmembrane region proteins (MCTPs) tether membranes at plasmodesmata

In eukaryotes, membrane contact sites (MCS) allow direct communication between organelles. Plants have evolved a unique type of MCS, inside intercellular pores, the plasmodesmata, where endoplasmic reticulum (ER)-plasma membrane (PM) contacts coincide with regulation of cell-to-cell signalling. The molecular mechanism and function of membrane tethering within plasmodesmata remain unknown. Here, we show that the multiple C2 domains and transmembrane region protein (MCTP) family, key regulators of cell-to-cell signalling in plants, act as ER-PM tethers specifically at plasmodesmata. We report that MCTPs are plasmodesmata proteins that insert into the ER via their transmembrane region while their C2 domains dock to the PM through interaction with anionic phospholipids. A Atmctp3/Atmctp4 loss of function mutant induces plant developmental defects, impaired plasmodesmata function and composition, while MCTP4 expression in a yeast Δtether mutant partially restores ER-PM tethering. Our data suggest that MCTPs are unique membrane tethers controlling both ER-PM contacts and cell-to-cell signalling.

Evaluation of supportive care needs: Comparison between patients and physicians’ perception

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Background: In order to optimize supportive care for cancer patients, we proposed them to fill a short questionnaire evaluating their potential complaints and we evaluated the concordance of their answers with the perception of their referent physician. Methods: Patients seen in consultation in an oncology unit were proposed to answer anonymously to 7 questions designed to identify potential social, psychological, nutritional problems or uncontrolled pain. Their physician answered to a similar questionnaire. Physicians were blinded to patients’ answers. Results: 155 patients accepted to complete the questionnaire. Median age was 60 yrs [21–85], 45% of patients were in metastatic setting. 70% of patients reported at least one problem, especially in the field of potential social problems (35%) or sleep disorders (25%). Concordance between patients and physicians was high for psychological support need (81%) or nutritional problems (87%) but was lower for social problems (62%) or uncontrolled pain (69%). Physicians tended to underestimate patients’ problems and missed social issues for 30% of patients or sleep disorders for 18% of patients. On the contrary and surprisingly, physicians overestimate patients’ complaints about uncontrolled pain (underestimation in 9% of cases but overestimation in 20% of cases for the item). Conclusions: Discordance between physicians and patients’ perception of supportive care needs emphasizes the importance of extending the use of screening tolls in daily practice.

No significant financial relationships to disclose.

[Complications due to peripheral venous catheterization. Prospective study]

OBJECTIVE

Peripheral venous catheter (PVC)-associated complications were prospectively evaluated in a 2 month-study performed in 3 different wards.

METHODS

For each inserted PVC, the following complications were observed daily by an external investigator: tenderness, erythema, swelling or induration, palpable cord and purulence. PVC that were removed were systematically sent to the Microbiology department and analysed according to the semi-quantitative method described by Brun-Buisson et al.

RESULTS

A total of 525 PVC (corresponding to 1,036 catheterisation-days) were included. Main clinical complications were erythema (22.1%), tenderness (21.9%), swelling or induration (20.9%), palpable cord (2.7%) and purulence (0.2%). Phlebitis, defined by 2 or more of the following signs: tenderness, erythema, swelling or induration and palpable cord, was observed in 22%. Catheter colonization (> or = 103 CFU/ml) occurred in 13%. Bacteria isolated from colonized catheters were coagulase-negative staphylococci (88.1%), Staphylococcus aureus (7.1%) and Candida sp. (4.8%). Multivariate risk factor analysis showed that age > or = 55 y. (OR = 3.16, p = 0.003), insertion on articulation site (OR = 2.94, p = 0.01) or in jugular vein (OR = 8.18, p = 0.01) and > 72 hour-catheterisation (OR = 4.74, p = 0.0003) were significantly associated with PVC colonization. Risk factors for phlebitis were skin lesions (OR = 1.88, p < 0.016), active infection unrelated to PVC (OR = 2.8, p = 0.001), "poor quality" peripheral vein (OR = 2.46, p < 0.02) and > 72 hour-catherisation (OR = 2.38, p = 0.009).

CONCLUSION

Complications associated with peripheral venous catheters are frequent but remain benign. They could probably be reduced by a systematic change every 72-96 hours as recommended by different guidelines.

Excess sludge reduction in activated sludge processes by integrating biomass alkaline heat treatment

With new EC regulations, alternative treatment and disposal techniques of the excess sludge produced by activated sludge wastewater treatment plants have to be developed. To decrease activated sludge production yield, microbial cell lysis can be amplified to enhance cryptic growth (biomass growth on lysates). Cell breakage techniques (thermal, alkaline and a combination) were studied to generate Ralstonia eutropha (strain model) and waste activated sludge lysates and to evaluate their biodegradability. Gentle treatment conditions by alkaline waste treatment (20 min at 60 degrees C and pH 10 by NaOH addition) allowed waste activated sludge to be solubilized by a two step process (instantaneous and post-treatment) giving a dissolved organic carbon released by the total suspended solids treated of 267 mgDOC x g(-1)TSS. The biodegradation of the soluble fraction of the lysates by fresh sludge reached 75 and 90% after 48 and 350 hrs of incubation respectively. A validation on a laboratory scale by insertion of a liquor alkaline heat treatment loop in a biological synthetic wastewater treatment process was carried out. A reduction of 37% of the excess sludge was obtained without altering the purification yield of the process.

Towards a reduction in excess sludge production in activated sludge processes: biomass physicochemical treatment and biodegradation

To decrease activated sludge production, microbial cell lysis can be amplified to enhance cryptic growth (biomass growth on lysates). Cell breakage techniques (thermal, alkaline, acid) were studied to generate Alcaligenes eutrophus and sludge lysates and to evaluate their biodegradability. Gentle treatment conditions produced the best results. Complete cell deactivation was obtained for temperatures higher than 55 degrees C. The release kinetics were similar for temperatures varying from 60 degrees C to 100 degrees C. A 20-min incubation was suitable for reaching 80% of the maximum releasable carbon. In thermal-chemical hydrolysis, NaOH was the most efficient for inducing cell lysis. Carbon release was a two-step process. First an immediate release occurred, which was of the same order of magnitude for A. eutrophus and sludge [100-200 mg dissolved organic C (DOC) g total suspended solids (TSS)-1], followed by a post-treatment release. The second step was virtually equivalent to the first for sludge, and weaker for A. eutrophus (< 50 mg DOC g TSS-1). The biodegradability of the soluble fraction, both the immediate and the post-treatment carbon release, was investigated. The optimal degradation yield, obtained with sludge cells, reached 55% after 48 h of incubation and 80% after 350 h. The most consistent lysis and biodegradation results occurred at pH 10 and 60 degrees C after a 20-min incubation.

Effects of Low Dissolved-Oxygen Concentrations on Poly-(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Production by Alcaligenes eutrophus

The bacterial copolyester poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) was produced with Alcaligenes eutrophus DSM 545 from glucose and sodium propionate in a fed-batch fermentation with both nitrogen limitation and low dissolved-oxygen concentrations. When the dissolved-oxygen content was kept between 1 and 4% of air saturation during the polymer accumulation phase, the yield of 3-hydroxybutyrate (3HB) monomer from glucose was not affected, but the propionate-to-3-hydroxyvalerate (3HV) monomer yield was two to three times (0.48 to 0.73 mol of 3HV mol of propionate consumed(sup-1)) that observed in a control experiment (0.25 mol mol(sup-1)), where the accumulation-phase dissolved-oxygen concentration was 50 to 70% of air saturation. The overall polymer productivity of the fermentation was somewhat decreased by low dissolved-oxygen contents, owing to a slower 3HB production rate. The effect of a low dissolved-oxygen concentration is probably attributable to a reduction of the oxygen-requiring decarbonylation of propionyl-coenzyme A (CoA) to acetyl-CoA.

Biological activity of retinoids correlates with affinity for nuclear receptors but not for cytosolic binding protein

In order to better understand the respective roles of the nuclear retinoic acid receptors (RARs) and the cytosolic retinoic acid binding protein (CRABP) in the mode of action of retinoic acid (RA), several types of RA analogs have been synthesized. Representative compounds have been radiolabeled to a high specific activity and their binding (direct and competition) to RARs and CRABP was determined. Their biological activity on F9 embryonal carcinoma cell differentiation has been determined by a quantitative assay of plasminogen activator (PA). All biologically active analogs studied in this work bound to RARs. A good correlation was found between PA induction and affinity for the RARs, with the exception of RA itself which was a good ligand but a moderate inducer of F9 differentiation. Two biologically active analogs (compounds II and III) did not bind to the CRABP. One biologically inactive analog (compound VIII) bound to CRABP. These results strongly suggest that retinoids must bind to RARs but not necessarily to CRABP in order to induce cell differentiation in F9 cells.