Background The formation of by-products, mainly acetone in acetone-butanol-ethanol (ABE) fermentation, significantly affects the solvent yield and downstream separation process. In this study, we genetically engineered Clostridium acetobutylicum XY16 isolated by our lab to eliminate acetone production and altered ABE to isopropanol-butanol-ethanol (IBE). Meanwhile, process optimization under pH...

i ntroduction: many of highly-alkaline dental materials have some adverse effects on physical properties of dentin. as basic substances, mineral trioxide aggregate (mta), calcium hydroxide (ch) and the new endodontic material, calcium-enriched mixture (cem) cement, may adversely affect dentin. the purpose of this in vitro study was to evaluate the effect of long-term application of cem cement, ...

Cell-based functional assays used for compound screening and lead optimization play an important role in drug discovery for G-protein coupled receptors (GPCRs). Cell-based assays can define the role of a compound as an agonist, antagonist or inverse agonist and can provide detailed information about the potency and efficacy of a compound. In addition, cell-based screens can be used to identify ...

background: different techniques have been introduced to improve removing the calcium hydroxide intra-canal dressing. the purpose of this study was to compare the effi ciency of passive ultrasonic irrigation (pui) and rinsendo system in the removal of calcium hydroxide from root canal system. materials and methods: access cavities were prepared in 50 single-rooted anterior teeth. cleaning and s...

Abstract: In recent years, new technologies in neuroscience have made it possible to measure the activities of large numbers of neurons in behaving animals. For each neuron, a fluorescence trace is measured; this can be seen as a first-order approximation of the neuron’s activity over time. Determining the exact time at which a neuron spikes on the basis of its fluorescence trace is an importan...

Acquisition of oocyte developmental competence needs to be understood to improve clinical outcomes of assisted reproduction. The stimulation of cumulus cell concentration of cyclic adenosine 3'5'-monophosphate (cAMP) by pharmacological agents during in vitro maturation (IVM) participates in improvement of oocyte quality. However, precise coordination and downstream targets of cAMP signaling in ...

in this study, the possible involvement of l-type voltage-operated calcium channels in the vasorelaxant effect of the flavonoid quercetin was investigated, using the isolated aortic rings from normal male rats. addition of quercetin (0.1 µm-1 mm) caused a significant dose-dependent relaxation of noradrenaline (na)- and kcl-preconstricted rings and nifedipine attenuated this response, especially...

background: although it is assumed that calcium has beneficial effects on weight loss, the interaction of calcium and iron would be a major concern. we did this study to investigate the effects of calcium and low-fat milk on serum ferritin in overweight or obese premenopausal women.   methods: sixty-four healthy overweight or obese premenopausal women recruited in shahid beheshti university of ...

there is growing evidence indicating that neuronal calcium channels play an important role in the mechanism of morphine dependence. in this study, the effects of acute and chronic administration of nitrendipine on naloxone precipitated morphine withdrawal signs were investigated. mice were rendered dependent to morphine by subcutaneous injection of morphine over a period of 5 days. in chronic s...

calcium-binding proteins play essential roles in the cell. one important class of calcium-binding proteins is the annexin family. this is a family of 13 proteins, which binds to phospholipids in a calcium-dependent manner. osteosarcoma cell line (mg-63) is a transformed cell that has many characteristics of the differentiated cell, such as a considerable serum dependency in its growth rate. usi...