Management of apple scab (Venturia inaequalis) in Romania based on electronic warnings

Apple scab, Venturia inaequalis (Cke) Wint., is a major problem in Romanian apple orchards and is responsible for serious economic losses. The purchase of spraying equipment and phytopharmaceutical products is very expensive in comparison to the income of local apple growers. This is one of the reasons why reduced fungicide sprayings are becoming more and more important. That's why a project was started to investigate the influence of West-European control measures and to improve interaction between local apple growers and research facilities. This experiment took place in an orchard of the university of Timisoara (USABT), where occurrence of apple scab was very high, and in a well managed commercial orchard, both in the Banat region. In July 2006, a comparative study between a traditional Romanian management program, a calendar-based program and a computerized weather-based management program was conducted. Four test plots were taken. The sprayments in plot 1 happened according to the integrated computerized model. No sprayings took place in plot 2. In plot 3 were some sprayments done with sulphur according to the traditional Romanian program. The sprayings in plot 4 were done following a calendar-based spraying program. The products that were used for the sprayments were all easy to obtain in Romania such as dodine (Sillit flow), dithianon (Delan flow), difenoconazole (Score), pyrimethanil (Scala), metiram (Polyram), kresoxim-methyl (Stroby). The occurrence of scab in plot 1 was very low in comparison to the other plots. Analysing the data, on average, the treatments done in plot 1 caused about 50% less damage than the traditional sprayings. This indicated that with a relative small amount of well timed sprayings a enormous amount of damage can be prevented. A calendar-based management program seems to be less effective (more sprayings needed and the results are worse). These results also emphasize the importance of the development of an adequate apple scab management program that should be presented to local apple growers.     

Variation of the folding and dynamics of the Escherichia coli chromosome with growth conditions

We examine whether the Escherichia coli chromosome is folded into a self‐adherent nucleoprotein complex, or alternately is a confined but otherwise unconstrained self‐avoiding polymer. We address this through in vivo visualization, using an inducible GFP fusion to the nucleoid‐associated protein Fis to non‐specifically decorate the entire chromosome. For a range of different growth conditions, the chromosome is a compact structure that does not fill the volume of the cell, and which moves from the new pole to the cell centre. During rapid growth, chromosome segregation occurs well before cell division, with daughter chromosomes coupled by a thin inter‐daughter filament before complete segregation, whereas during slow growth chromosomes stay adjacent until cell division occurs. Image correlation analysis indicates that sub‐nucleoid structure is stable on a 1 min timescale, comparable to the timescale for redistribution time measured for GFP–Fis after photobleaching. Optical deconvolution and writhe calculation analysis indicate that the nucleoid has a large‐scale coiled organization rather than being an amorphous mass. Our observations are consistent with the chromosome having a self‐adherent filament organization.     

Impact of α-lipoic acid on liver peroxisome proliferator-activated receptor-α, vascular remodeling, and oxidative stress in insulin-resistant rats

This study sought to determine the impact of α-lipoic acid (LA) on superoxide anion (O(2)(?-)) production and peroxisome proliferator-activated receptor-α (PPARα) expression in liver tissue, plasma free fatty acids (FFA), and aortic remodeling in a rat model of insulin resistance. Sprague-Dawley rats (50-75 g) were given either tap water or a drinking solution containing 10% D-glucose for 14 weeks, combined with a diet with or without LA supplement. O(2)(?-) production was measured by lucigenin chemiluminescence, and PPAR-α expression by Western blotting. Cross-sectional area (CSA) of the aortic media and lumen and number of smooth muscle cells (SMC) were determined histologically. Glucose increased systolic blood pressure (SBP), plasma levels of glucose and insulin, and insulin resistance (HOMA index). All of these effects were attenuated by LA. Whereas glucose had no effect on liver PPAR-α protein level, it decreased plasma FFA. LA decreased the aortic and liver O(2)(?-) production, body weight, and plasma FFA levels in control and glucose-treated rats. Liver PPAR-α protein levels were increased by LA, and negatively correlated with plasma FFA. Medial CSA was reduced in all glucose-treated rats, and positively correlated with plasma FFA but not with SBP or aortic O(2)(?-) production. Glucose also reduced aortic lumen area, so that the media-to-lumen ratio remained unchanged. The ability of LA to lower plasma FFA appears to be mediated, in part, by increased hepatic PPAR-α expression, which may positively affect insulin resistance. Glucose-fed rats may serve as a unique model of aortic atrophic remodeling in hypertension and early metabolic syndrome.     

Overexpression of miR-125a in Myelodysplastic Syndrome CD34+ Cells Modulates NF-κB Activation and Enhances Erythroid Differentiation Arrest

Myelodysplastic syndromes (MDS) are characterized by impaired proliferation and differentiation of hematopoietic stem cells. The participation of toll-like receptor (TLR)-mediated signaling in MDS is well documented. Increased TLR signaling leads to the constitutive activation of NF-κB, which mediates inflammation, cell proliferation and apoptosis. In addition, the TLR pathway induces the expression of miRNAs which participate in the fine-tuning of the inflammatory response. miRNAs also regulate other biological processes, including hematopoiesis. miR-125a and miR-125b are known modulators of hematopoiesis and are abnormally expressed in several hematologic malignancies. However, little is known about their role in MDS. NF-κB-activating ability has been described for both miRNAs. We studied the role of miR-125a/miR-125b in MDS and their relationship with TLR signaling and hematopoietic differentiation. Our results indicate that miR-125a is significantly overexpressed in MDS patients and correlates negatively with patient survival. Expression of miR-99b, which is clustered with miR-125a, is also directly correlated with prognosis of MDS. Both miR-125a and miR-99b activated NF-κB in vitro; however, we observed a negative correlation between miR-99b expression and the levels of TLR2, TLR7 and two downstream genes, suggesting that NF-κB activation by the miRNA cluster occurs in the absence of TLR signaling. We also show that TLR7 is negatively correlated with patient survival in MDS. In addition, our data suggest that miR-125a may act as an NF-κB inhibitor upon TLR stimulation. These results indicate that miR-125a is involved in the fine-tuning of NF-κB activity and that its effects may depend on the status of the TLR pathway. Furthermore, we observed that miR-125a inhibits erythroid differentiation in leukemia and MDS cell lines. Therefore, this miRNA could serve as a prognostic marker and a potential therapeutic target in MDS.