Thermosensitive phenotype of transgenic mice overproducing human glutathione peroxidases.

Exposure of humans and other mammals to hyperthermic conditions elicits many physiological responses to stress in various tissues leading to profound injuries, which eventually result in death. It has been suggested that hyperthermia may increase oxidative stress in tissues to form reactive oxygen species harmful to cellular functions. By using transgenic mice with human antioxidant genes, we demonstrate that the overproduction of glutathione peroxidase (GP, both extracellular and intracellular) leads to a thermosensitive phenotype, whereas the overproduction of Cu,Zn-superoxide dismutase has no effect on the thermosensitivity of transgenic mice. Induction of HSP70 in brain, lung, and muscle in GP transgenic mice at elevated temperature was significantly inhibited in comparison to normal animals. Measurement of peroxide production in regions normally displaying induction of HSP70 under hyperthermia revealed high levels of peroxides in normal mice and low levels in GP transgenic mice. There was also a significant difference between normal and intracellular GP transgenic mice in level of prostaglandin E2 in hypothalamus and cerebellum. These data suggest direct participation of peroxides in induction of cytoprotective proteins (HSP70) and cellular mechanisms regulating body temperature. GP transgenic mice provide a model for studying thermoregulation and processes involving actions of hydroxy and lipid peroxides in mammals.

Some examples of modeling in chemical engineering: thermal treatment of polymers, phase equilibrium calculations and process design

Presentation submitted to PSE Seminar, Chemical Engineering Department, Center for Advanced Process Design-making (CAPD), Carnegie Mellon University, Pittsburgh (USA), October 2012.

Coordination polymers, metal–organic frameworks and the need for terminology guidelines

Coordination polymers (CPs) and metal–organic frameworks (MOFs) are among the most prolific research areas of inorganic chemistry and crystal engineering in the last 15 years, and yet it still seems that consensus is lacking about what they really are, or are not.

Terminology of metal–organic frameworks and coordination polymers (IUPAC Recommendations 2013)

A set of terms, definitions, and recommendations is provided for use in the classification of coordination polymers, networks, and metal–organic frameworks (MOFs). A hierarchical terminology is recommended in which the most general term is coordination polymer. Coordination networks are a subset of coordination polymers and MOFs a further subset of coordination networks. One of the criteria an MOF needs to fulfill is that it contains potential voids, but no physical measurements of porosity or other properties are demanded per se. The use of topology and topology descriptors to enhance the description of crystal structures of MOFs and 3D-coordination polymers is furthermore strongly recommended.

Rapid carbon nanotubes suspension in organic solvents using organosilicon polymers

A strategy for a simple dispersion of commercial multi-walled carbon nanotubes (MWCNTs) using two organosilicones, polycarbosilane SMP10 and polysilazane Ceraset PSZ20, in organic solvents such as cyclohexane, tetrahydrofuran (THF), m-xylene and chloroform is presented. In just a few minutes the combined action of sonication and the presence of Pt(0) catalyst is sufficient to obtain a homogeneous suspension, thanks to the rapid hydrosilylation reaction between SiH groups of the polymer and the CNT sidewall. The as-produced suspensions have a particle size distribution <1μm and remain unchanged after several months. A maximum of 0.47 and 0.50mg/ml was achieved, respectively, for Ceraset in THF and SMP10 in chloroform. Possible applications as polymeric and ceramic thin films or aerogels are presented.

Radiation-induced reactions in swollen polymers /

The content was printed on only one side of the paper.

Radiation-induced reactions in swollen polymers /

The content was printed on only one side of the paper.

Infrared spectra of polymers and resins.

Cover title: Infrared spectra of plastics and resins.

Synthesis and evaluation of new polymers prepared by sterospecific catalysis. Materials Central, Contract no. AF33(616)-6866, Project no. 7340.

"Prepared by the Polytechnic Institute of Brooklyn...under the supervision of Dr. C.G. Overberger."

Rheology of polymers

Mode of access: Internet.

Fundamentals of high polymers.

Includes bibliography.

Mechanical properties of polymers.

Includes bibliographical references.

Polymers and resins: their chemistry and chemical engineering.

Includes bibliography.

Synthesis of acetoxy stabilised indolequinones as precursors to model eumelanin polymers

We report an efficient synthetic route to obtaining a stable analogue of 5,6-dihydroxyindole. These analogues can be used to build controlled composition model melanin biopolymers for solid state and spectroscopic studies of this important biomolecule.

Controlling PbS nanocrystal aggregation in conducting polymers

PbS nanocrystals were synthesized directly in the conducting polymer, poly (3 -hexylthiophene-2,5-diyl). Transmission electron microscopy shows that the PbS nanocrystals are faceted and relatively uniform in size with a mean size of 10 nm. FFT analysis of the atomic lattice planes observed in TEM and selected area electron diffraction confirm that the nanocrystals have the PbS rock salt structure. The synthesis conditions are explored to show control over the aggregation of PbS nanocrystals in the thiophene conducting polymer.