Automated Technology for Performing Flow-Chemistry at Elevated Temperature and Pressure

Over the past few years, a series of novel microfluidic-based instruments were developed by ThalesNano, Inc. to carry out dangerous and difficult to perform chemical reactions in a safe and fast manner, resulting in superior performance to what commercial batch reactors could provide. Importance of microfluidic devices is continuously raising, as seen there are more and more publications, applications and devices in this field expanding the borders of chemistry. Furthermore, as one of the main advantages for pharmaceutical applications, these new revolutionary reactors allow the fast, on-the-fly mode optimization of different heterogeneous reactions in a high-throughput fashion. The heart of the reactor systems is the actual reactor bed, called the CatCart system. CatCarts allow easy handling of heterogeneous catalyst or immobilized reagents without further purification of products. In addition, the shoe-box size of these reactors makes them available from laboratories to industrial applications.     

Cell wall proteins of Kluyveromyces fragilis: Surface and emulsifying properties

Yeast cell wall proteins were extracted from homogenized suspensions with 0.75 mol/l NaOH, yielding after precipitation at isoelectric pH a pale-brown sediment. Lyophilized sample was fractionated on Sephadex G-50 to yield three fractions (Fr 1, Fr 2 and Fr 3). Fr 1, which had the highest yields and protein content, showed the highest molecular weight and best surface properties. Fr 2 and Fr 3 were mainly composed by polysaccharide-protein complexes. Fr 1 was further subfractionated on Sephacryl S-300 to produce three fractions (Fr A, Fr B and Fr C). All subfractions, turned out to be highly foamy during evaporation. The highest yields were obtained for Fr A, which also showed the highest molecular weight. Fractions Fr 1 and their subfractions Fr B and Fr C exhibited good surface activity and high emulsifying activity. Emulsions prepared with these fractions were the most stable against creaming and coalescence. Fr 2 cream phase presented a gel-like behavior as a consequence of polysaccharides acting as thickening agents.     

The evolution of inertia

This article examines some evolutionary consequences of architecturalinertia in organizations. The main theorem holds that selectionfavors architectural inertia in the sense that the median levelof inertia in a closed population of organizations increasesover time. The other key theorems hold that the selection intensityfavoring architectural inertia increases with the levels ofintricacy and structural opacity and decreases with culturalasperity.     

Cinnamoyl esters of lesquerella and castor oil: Novel sunscreen active ingredients

Lesquerella and castor oils were esterified with cinnamic acid (CA) and 4-methoxycinnamic acid (MCA). Esterification of the hydroxy oils reached 85% completion with CA and 50% conversion with MCA. The hydroxy oils were esterified at 200°C under a nitrogen atmosphere within a sealed system. Unreacted CA and MCA were removed from the reaction mixtures by sublimation at 100°C under vacuum. The resultant methoxycinnamic oils possessed a broader, more blue-shifted UV absorbance, 250 to 345 nm with a λ_max of 305 nm, compared with the cinnamic oils, which absorbed from 260 to 315 nm, λ_max of 270 nm. The methoxycinnamic oils provide better UV-B absorption and thus are better candidates to be used as sunscreen active ingredients. Esterifications of the hydroxy oils with MCA at 200°C resulted in conversion of 40% of the MCA to undesirable by-products. Esterifications with MCA performed at 175°C in the presence of a tin catalyst resulted in similar percent conversions to product without degradation of MCA. Esterifications of lesquerella oil with MCA at 175°C resulted in higher conversions, 43%, than analogous esterifications with castor oil, 29%. The hydroxyl groups of the lesquerella and castor oils provide their excellent emolliency, lubricity, and noncomedogenicity in skin and personal-care products. Therefore, reactions that convert only 50% of the available hydroxyl groups of the lesquerella oil to cinnamoyl-esters are preferred.     

Rapid broth macrodilution method for determination of MICs for Mycobacterium avium isolates

A multicenter study was done to investigate the accuracy and reproducibility of a method for determining the MICs of antimicrobial agents against the Mycobacterium avium complex in 7H12 broth with the BACTEC system. In phase I, with eight drugs and 10 strains, intralaboratory reproducibility was 95.7 to 100%, allowing a 1-dilution difference upon repeat testing. The results of phase II testing with 41 additional strains were consistent with those obtained in phase I, with good interlaboratory reproducibility. The radiometric method was validated by sampling and plating of the same broth cultures and determining, by the number of CFU per milliliter, the lowest drug concentration that inhibited more than 99% of the initial bacterial population. Three test concentrations of each drug and the tentative interpretation of results are proposed. Radiometric MIC determination has the potential to become the method of choice for clinical microbiology laboratories and evaluation of new agents for the treatment of M. avium infections, both pulmonary and disseminated.     

Effect of sodium iodide additive on the electrochemical performance of sodium/nickel chloride cells

The effect of sodium iodide and sulfur additives on the performance of Na/-alumina/NaAlCl₄/NiCl₂/Ni cells was investigated in quasi-sealed laboratory research cells (0.5–1.0 Ah capacity) and in sealed full-size cells (4 Ah capacity). It was found that sodium iodide additive especially in combination with sulfur in Na/NiCl₂ cells significantly increases the usable capacity and reduces the impedance of the Na/NiCl₂ cells. It is proposed that the use of sodium iodide enhances the energy and power performance of the NiCl₂ electrode by two different mechanisms. The first mechanism, iodide ion doping of the anodically formed solid NiCl₂, is dominant at potentials lower than that of iodine evolution. The doping effect of the iodide ions produces a higher-capacity, lower-impedance NiCl₂ layer on the positive electrode. The second mechanism, anodic formation of very reactive iodine species, is effective when the cell is cycled through the iodine evolution potential range (2.8–3.1 V vs Na). During this process, the dissolved iodine species improve electrode kinetics through liquid-phase mass transport. Use of the sodium iodide additive is safe in sealed cells, causing no over-pressurizing problems. A maximum pressure increase of only 10 kPa was detected by a pressure sensor during severe overcharge tests.     

Proteomics Complementation of the Rat Uterotrophic Assay for Estrogenic Endocrine Disruptors: A Roadmap of Advancing High Resolution Mass Spectrometry-Based Shotgun Survey to Targeted Biomarker Quantifications

The widely used rat uterotrophic assay to assess known and potential estrogenic compounds only considers uterine weight gain as endpoint measurement. To complement this method with an advanced technology that reveals molecular targets, we analyzed changes in protein expression using label-free quantitative proteomics by nanoflow liquid chromatography coupled with high-resolution mass spectrometry and tandem mass spectrometry from uterine protein extracts of ovariectomized rats after daily 17β-estradiol exposure for five days in comparison with those of vehicle-treated control animals. Our discovery-driven study revealed 165 uterine proteins significantly regulated by estrogen treatment and mapped by pathway analyses. Estrogen-regulated proteins represented cell death, survival and development, cellular growth and proliferation, and protein synthesis as top molecular and cellular functions, and a network found with the presence of nuclear estrogen receptor(s) as a prominent molecular node confirmed the relevance of our findings to hormone-associated events. An exploratory application of targeted proteomics to bisphenol A as a well-known example of an estrogenic endocrine disruptor is also presented. Overall, the results of this study have demonstrated the power of combining untargeted and targeted quantitative proteomic strategies to identify and verify candidate molecular markers for the evaluation of endocrine-disrupting chemicals to complement a conventional bioassay.