Kratom Alkaloids: A Blood-Brain Barrier Specific Membrane Permeability Assay-Guided Isolation and Cyclodextrin Complexation Study.

Mitragynine is an "atypic opioid" analgesic with an alternative mechanism of action and a favorable side-effect profile. Our aim was to optimize the alkaloid extraction procedure from kratom leaves and to determine and isolate the most relevant compounds capable of penetrating the central nervous system. The PAMPA-BBB study revealed that mitragynine and its coalkaloids, speciociliatine, speciogynine, and paynantheine, possess excellent in vitro BBB permeability.

Influence of fullerene content on the properties of polyurethane resins: A study of rheology and thermal characteristics.

The effect of different contents of fullerene on the properties of polyurethane resins (PUs), including rheology and thermal properties, was investigated. Polyurethane resins were prepared through polyaddition reactions using different isocyanate monomers such as isophorone diisocyanate (IPDI), methylene diphenyl diisocyanate (MDI), hexamethylene diisocyanate (HDI), and different polyols, such as poly(oxytetramethylene) glycol (PTMG), the triol trade name FA-703, and polypropylene glycols (PPG), at an NCO/OH ratio 0.94 and a temperature of 100 °C.

[State of cardiac pyridine nucleotides and flavoproteins during preservation with a 0.5% formalin solution].

Possibilities of formaldehyde interaction with the respiratory link of mitochondria were studied. For this purpose the fluorescent technique was used to examine pyridine nucleotides and flavoproteins of the conserved heart. The data obtained indicate that the action of formaldehyde on oxidation myocardial cell metabolism appears to be related to the inhibition of the glycolytic apparatus.

[Respiratory chain of rat heart mitochondria during heart preservation in formaldehyde].

It has been shown by the method of low-temperature ESR-spectroscopy that partial blocking with formaldehyde of electron intake into the respiratory chain promotes the maintenance of a definite level of oxidation in the respiratory chain carriers and preservation of its nativity.