Genotype-level interactions determine the degree of reduction of leaf rust on wheat by seed application of beneficial Pseudomonas spp.

Some bacteria have the capacity to reduce incidence and severity of plant diseases either by inhibiting the pathogen or by modulating the resistance response of the plant. Plants dispose of different resistance mechanisms that are influenced by the biotic and abiotic environment. The present experiments explored the effects of biocontrol strains of Pseudomonas fluorescens on the resistance of wheat varieties against brown rust disease caused by Puccinia triticina. Root inoculation with biocontrol pseudomonads reduced the disease severity on the leaves. The plant response depended on the genotype of both the microbes and the wheat varieties, suggesting a straight interaction at the molecular level.

Surgical glues: are they really adhesive?

OBJECTIVE: The aim of this study is to create a standard test to approve the efficacy of a surgical sealant. An industrial test, the bulge-and-blister test, which is very convenient for measuring adhesion energy, is applied to the surgical field to quantify adhesion of bioadhesives. METHODS: Samples were composed of two circular layers of equine pericardium glued by the surgical sealant studied. The sample was fixed to a support with an industrial glue. The support and the bottom layer were perforated in the centre to allow injection of pressurised water. Water was progressively introduced through the hole in the support and the bottom layer to create a blister with constant radius, increasing height and internal pressure during this first step. At a critical pressure, delamination started, the radius and height of the blister increased and the pressure decreased. At this point, the adhesion energy could be determined. The experimental parameters were measured with a pressure sensor and an optical profilometry device for deflection. RESULTS: Adhesion testing was carried out in eight paired equine pericardium samples bonded with a Dermabond cyanoacrylate glue. The average value of the practical adhesion energy is 2.3 Jm(-2) with a standard deviation of 1.5 Jm(-2). CONCLUSION: Application of the bulge-and-blister test to the surgical field was achieved and allowed a quantification of adhesion of a surgical glue. Such information is essential to compare the different surgical glues presently available. The study of the impact of bonding conditions such as pressure, hygrometry or setting conditions will provide a better understanding of the characteristics of adhesion in the surgical field.

Transcutaneous carbon dioxide tension in newborn infants: reliability and safety of continuous 24-hour measurement at 42 degrees C.

In 58 newborn infants a new iridium oxide sensor was evaluated for transcutaneous carbon dioxide (tcPCO2) monitoring at 42 degrees C with a prolonged fixation time of 24 hours. The correlation of tcPCO2 (y; mm Hg) v PaCO2 (x; mm Hg) for 586 paired values was: y = 4.6 + 1.45x; r = .89; syx = 6.1 mm Hg. The correlation was not influenced by the duration of fixation. The transcutaneous sensor detected hypocapnia (PaCO2 less than 35 mm Hg) in 74% and hypercapnia (PCO2 greater than 45 mm Hg) in 74% of all cases. After 24 hours, calibration shifts were less than 4 mm Hg in 90% of the measuring periods. In 86% of the infants, no skin changes were observed; in 12% of infants, there were transitional skin erythemas and in 2% a blister which disappeared without scarring. In newborn infants with normal BPs, continuous tcPCO2 monitoring at 42 degrees C can be extended for as many as 24 hours without loss of reliability or increased risk for skin burns.

Identification of novel elements of the Drosophila blisterome sheds light on potential pathological mechanisms of several human diseases.

Main developmental programs are highly conserved among species of the animal kingdom. Improper execution of these programs often leads to progression of various diseases and disorders. Here we focused on Drosophila wing tissue morphogenesis, a fairly complex developmental program, one of the steps of which - apposition of the dorsal and ventral wing sheets during metamorphosis - is mediated by integrins. Disruption of this apposition leads to wing blistering which serves as an easily screenable phenotype for components regulating this process. By means of RNAi-silencing technique and the blister phenotype as readout, we identify numerous novel proteins potentially involved in wing sheet adhesion. Remarkably, our results reveal not only participants of the integrin-mediated machinery, but also components of other cellular processes, e.g. cell cycle, RNA splicing, and vesicular trafficking. With the use of bioinformatics tools, these data are assembled into a large blisterome network. Analysis of human orthologues of the Drosophila blisterome components shows that many disease-related genes may contribute to cell adhesion implementation, providing hints on possible mechanisms of these human pathologies.

Controlled delivery of 5-chlorouracil using poly(ortho esters) in filtering surgery for glaucoma.

PURPOSE: To evaluate the antimitotic and toxic effects of 5-chlorouracil (5-CU) and 5-fluorouracil (5-FU) and study their potential to delay filtering bleb closure in the rabbit eye when released by poly(ortho esters) (POE). METHODS: Rabbit Tenon fibroblasts and human conjunctival cells were incubated with various 5-CU and 5-FU concentrations. Antiproliferative effects and toxicity were evaluated at 24 and 72 hours by monotetrazolium, neutral red, and Hoechst tests and cell counting. Mechanisms of cell death were evaluated using TUNEL assay, annexin V binding, immunohistochemistry for anti-apoptosis-inducing factor (AIF) and LEI/L-DNase II. Trabeculectomy was performed in pigmented rabbits. Two hundred microliters of POE loaded with 1% wt/wt 5-FU or 5-CU was injected into the subconjunctival space after surgery. Intraocular pressure (IOP) and bleb persistence were monitored for 150 days. RESULTS: In vitro, 5-FU showed a higher antiproliferative effect and a more toxic effect than 5-CU. 5-FU induced cell necrosis, whereas 5-CU induced mostly apoptosis. The apoptosis induced by 5-CU was driven through a non-caspase-dependent pathway involving AIF and LEI/L-DNase II. In vivo, at 34 days after surgery, the mean IOP in the POE/5-CU-treated group was 83% of the baseline level and only 40% in the POE/5-FU-treated group. At 100 days after surgery, IOP was still decreased in the POE/5-CU group when compared with the controls and still inferior to the preoperative value. The mean long-term IOP, with all time points considered, was significantly (P < 0.0001) decreased in the POE/5-CU-treated group (6.0 +/- 2.4 mm Hg) when compared with both control groups, the trabeculectomy alone group (7.6 +/- 2.9 mm Hg), and the POE alone group (7.5 +/- 2.6 mm Hg). Histologic analysis showed evidence of functioning blebs in the POE-5-CU-treated eyes along with a preserved structure of the conjunctiva epithelium. CONCLUSIONS: The slow release of 5-CU from POE has a longstanding effect on the decrease of IOP after glaucoma-filtering surgery in the rabbit eye. Thus, the slow release of POE/5-CU may be beneficial for the prevention of bleb closure in patients who undergo complicated trabeculectomy.

T-Flux implant versus Healon GV in deep sclerectomy.

PURPOSE: To compare the efficacy and safety of T-Flux implant versus Healon GV in deep sclerectomy. METHODS: Randomized prospective trial of 23 eyes of 20 patients with medically uncontrolled open angle glaucoma over a period of 24 months, who underwent deep sclerectomy with either Healon GV or T-Flux implant. RESULTS: Mean postoperative intraocular pressure was 13.2 +/- 3.0 mm Hg with T-Flux implant (group 1) and 12.2 +/- 3.5 mm Hg with Healon GV (group 2), with a pressure reduction of 53.0% in group 1 (13.2 mm Hg vs. 28.1 mm Hg) and of 48.1% in group 2 (12.2 mm Hg vs. 23.5 mm Hg). Qualified and complete successes were 100% and 95.4% respectively. Pressures equal to or less than 15 mm Hg were 81.8% in group 1 and 90.9% in group 2 with or without treatment, and 63.6% in group 1 and 81.8% in group 2 without treatment. The number of glaucoma treatments dropped from 2.5 +/- 0.9 to 0.4 +/- 0.7 in group 1 and from 2.2 +/- 1.0 to 0.2 +/- 0.4 in group 2. The goniopuncture rate was 63.6% in group 1 and 36.4% in group 2, with a mean pressure drop of 6.1 +/- 3.9 mm Hg and 3.25 +/- 1.2 mm Hg respectively. Overall, slit-lamp diagnosed surgery-related complications included positive Seidel (13.6%), hyphaema (22.7%), choroidal detachment, and iris incarceration (4.5% each). At 2 years, ultrasound biomicroscopy showed mainly low reflective (40.1%) and flattened (36.4%) blebs. Principally latter ones were associated with the need for adjunctive treatment. A hypoechoic area in the suprachoroidal space was seen in at least 59.1% of eyes at 2 years and was not associated with lower intraocular pressure. CONCLUSION: Deep sclerectomy is an effective and safe surgery. However, longer follow up and larger study groups are required to assess the additional benefit of nonabsorbable implants.