Identification of differential gene expression for <Emphasis Type="Italic">Kr1</Emphasis> gene in bread wheat using annealing control primer system

Intergeneric hybridization is an important strategy to introgress alien genes into common wheat for its improvement. But presence of cross ability barrier mechanism regulated by Kr1 gene played a major destructive role for hybridization than other reported genes. In order to know the underlying molecular mechanism and to dissect out this barrier, a new annealing system, ACP (anneling control primer) system was used in chromosome 5B (containing Kr1 gene) specific Recombinant Inbred Line (RIL) population. Two differentially expressed fragments for Kr1 gene was identified, cloned and sequenced. Further the expression was confirmed by northern blotting analysis. Sequence analysis of the resulted clones revealed classes of putative genes, including stress responsive and signal transduction.     

Isolated nodal failure after chemo-radiotherapy in limited disease small cell lung cancer (LD-SCLC)

BackgroundThe irradiation volume for treatment of limited disease small cell lung cancer (LD-SCLC), are still controversial. One of the aspects of radiation volume is the use of elective nodal irradiation (ENI), which has never been subjected to randomized study in SCLC patients.AimTo review retrospectively patterns of failure in relation to the radiation field after chemoradiotherapy (CHT-RT) in patients with limited disease small cell lung cancer (LD-SCLC).Material and MethodsBetween 1997 and 2006, 117 consecutive patients with LD-SCLC received chemotherapy with sequential radiotherapy (70%) and concurrent or alternating CHT-RT (30%). All but one case had predefined elective nodal irradiation (ENI) without inclusion of supraclavicular regions. Prophylactic cranial irradiation (PCI) was administered to 39% of patients.ResultsThe median follow-up for the 20 living patients was 33 months. The overall survival at 2 years was 36% (median survival: 18 months). In-field locoregional progression was observed in 42 patients (36%). Distant metastases occurred in 71 patients (61%). Five patients (4%) developed isolated nodal failure (INF) without local progression in the supraclavicular region. Patients with INF had N3 disease more often than those without INF (60% vs 21%, p = 0.04). There was 5% RTOG grade 3 or higher early radiation toxicity.ConclusionsINF failures are rare; however, the need for extension of ENI to supraclavicular areas may be reconsidered in N3 patients.     

Mechanisms of coupling between DNA recognition specificity and catalysis in EcoRI endonuclease

Proteins that bind to specific sites on DNA often do so in order to carry out catalysis or specific protein-protein interaction while bound to the recognition site. Functional specificity is enhanced if this second function is coupled to correct DNA site recognition. To analyze the structural and energetic basis of coupling between recognition and catalysis in EcoRI endonuclease, we have studied stereospecific phosphorothioate (PS) or methylphosphonate (PMe) substitutions at the scissile phosphate GpAATTC or at the adjacent phosphate GApATTC in combination with molecular-dynamics simulations of the catalytic center with bound Mg2+. The results show the roles in catalysis of individual phosphoryl oxygens and of DNA distortion and suggest that a "crosstalk ring" in the complex couples recognition to catalysis and couples the two catalytic sites to each other.     

Lithostratigraphy and carbonate microfacies across the Permian–Triassic boundary near Julfa (NW Iran) and in the Baghuk Mountains (Central Iran)

Permian–Triassic boundary sections in the Julfa (NW Iran) and Abadeh (Central Iran) regions display a succession of three characteristic rock units, (1) the Paratirolites Limestone with the mass extinction horizon at its top, (2) the ‘Boundary Clay’, and (3) the earliest Triassic Elikah Formation with the conodont P–Tr boundary at its base. The carbonate microfacies reveals a facies change, in the sections near Julfa, within the Paratirolites Limestone with an increasing number of intraclasts, Fe–Mn crusts, and biogenic encrustation. A decline in carbonate accumulation occurs towards the top of the unit with a sponge packstone in the sections, and finally resulting in a complete demise of the carbonate factory. The succession of the ‘Boundary Clay’ differs in the two regions; thin horizons of sponge packstone are present in the Julfa region and ‘calcite fans’ of probably inorganic origin in the Abadeh Region. The skeletal carbonate factory of the Late Permian was restored with the deposition of microbial carbonates at the base of the Elikah Formation, where densely laminated bindstone, floatstone with sparry calcite spheres, and oncoid wackestone/floatstone predominate.     

Molecular characterization of microbial mutations induced by ion beam irradiation

A positive selection system for gene disruption using a sucrose-sensitive transgenic rhizobium was established and used for the molecular characterization of mutations induced by ion beam irradiations. Single nucleotide substitutions, insertions, and deletions were found to occur in the sucrose sensitivity gene, sacB, when the reporter line was irradiated with highly accelerated carbon and iron ion beams. In all of the insertion lines, fragments of essentially the same sequence and of approximately 1188bp in size were identified in the sacB regions. In the deletion lines, iron ions showed a tendency to induce larger deletions than carbon ions, suggesting that higher LET beams cause larger deletions. We found also that ion beams, particularly "heavier" ion beams, can produce single gene disruptions and may present an effective alternative to transgenic approaches.     

Recycle use of immobilized glucoamylase by tangential flow filtration unit

Various properties of glucoamylase immobilized onto corn stover supporting material and separation of immobilized enzyme by tangential flow filtration unit were studied. Optimum pH and temperature of immobilized enzyme were 3.5 and 60 degrees C, respectively. Enzyme stability was studied in a packed-bed column. The starch conversion rate was attained at 81% for 15 days; after that, the hydrolysis rate gradually decreased. Size of supporting material proved to be an important factor, with higher activity and good loading yield resulting from smaller supporting material. Glucoamylase immobilized onto supporting material less than 44 mum was used for hydrolysis of 10% soluble starch at pH 3.5 and 40 degrees C for 3 h. Then immobilized glucoamylase was separated from the product by means of a tangential flow filtration unit using a 0.2-mum pore size Nylon 66 membrane filter. This operation was continued until 180 ml filtrate was obtained from a 260-mL starting volume. Then, the next batch was started by adding 180 mL starch substrate into the reactor. The batchwise experiments were repeated 20 times. The average filtration rate of each batch was determined and found to sharply decline during the first four batches. Thereafter, it gradually decreased from batch to batch. The cause of decreasing filtration rate appeared to be due to retrogradation of starch. The percentage of starch hydrolysis within 20 batches was in the range 89-96%. The filtration rate becomes higher if the hydrolyzation time is extended to 14 h. Resistance to filtration was also investigated. Almost all of the total resistance is related to insoluble materials, with the significant part of this from the resistance due to insoluble materials deposited on a surface of membrane and boundary layer resistance. Using a microscopic method, no microorganisms were found in the filtrate.     

Expression of cellular protective proteins SIRT1, HSP70 and SOD2 correlates with age and is significantly higher in NK cells of the oldest seniors

Magnesium (Mg) and calcium (Ca) are the principal essential elements involved in endothelial cell homeostasis. Extracellular changes in the levels of either alter endothelial contraction and dilatation. Consequently Mg and Ca imbalance is associated with a high risk of endothelial dysfunction, the main process observed during acute aortic dissection (AAD); in this clinical condition, which mainly affects elderly men, smooth muscle cell alterations lead to intimal tears, creating a false new lumen in the media of the aorta. AAD patients have a high risk of mortality as a result of late diagnosis because often it is not distinguished from other cardiovascular diseases. We investigated Mg and Ca total circulating levels and the associated pro-inflammatory mediators in elderly AAD patients, to gain further information on the pathophysiology of this disorder, with a view to suggesting newer and earlier potential biomarkers of AAD. Total circulating Mg and Ca levels were both lower in AAD patients than controls (p < 0.0001). Using Ca as cut-off, 90% of AAD patients with low Ca (<8.4 mg/dL) came into the type A classification of AAD. Stratifying AAD according to this cut-off, Mg was lower in patients with lower total Ca. Compared to controls, both type A and B AAD patients had higher levels of all the pro-coagulant and pro-inflammatory mediators analyzed, including sP-sel, D-dimer, TNF-α, IL-6, and CRP (p < 0.05). Dividing types A and B using the Stanford classification, no significant differences were found (p > 0.05) The levels of both ICAM-1 and EN-1 were lower in AAD than in a control group (p < 0.0001 and p < 0.05 respectively). These findings suggest that low Mg and Ca in AAD elderly patients may contribute to altering normal endothelial physiology and also concur in changing the normal concentrations of different mediators involved in vasodilatation and constriction, associated with AAD onset and severity.