Boron neutron capture therapy (BNCT) with Na2B12H11SH (BSH) or p-dihydroxyborylphenylalanine (BPA), and with a combination of both, was compared to radiotherapy with temozolomide, and the number of patients required to show statistically significant differences between the treatments was calculated. Whereas arms using BPA require excessive number of patients in each arm, a two-armed clinical trial with BSH and radiotherapy plus temozolomide is feasible.

The high-temperature (HT) phase of Y(BH(4))(3) has been prepared by heating of the as mechanochemically synthesised low-temperature (LT) phase of Y(BH(4))(3) to 194-216 °C and subsequent rapid cooling to ambient temperature. Although the differences in the crystal structure and vibrational spectra for these closely-related polymorphs are rather small, yet the NMR MAS (1)H and CP MAS (89)Y spectra reveal clear differences in the chemical shifts for both nuclei. The thermal decomposition process of both forms differs noticeably below 260 °C, decomposition being faster and more facile for the HT phase. The activation energy for thermal decomposition, calculated according to the Kissinger equation, is nearly three times lower for the HT than for the LT polymorph for the first step of the thermal decomposition signalling giant improvement of kinetics of H(2) desorption.

The single-turnover kinetic mechanism for the reaction catalyzed by dTDP-glucose 4,6-dehydratase (4,6-dehydratase) has been determined by rapid mix-chemical quench mass spectrometry. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was employed to analyze quenched samples. The results were compatible with the postulated reaction mechanism, in which NAD(+) initially oxidizes glucosyl C4 of dTDP-glucose to NADH and dTDP-4-ketoglucose. Next, water is eliminated between C5 and C6 of dTDP-4-ketoglucose to form dTDP-4-ketoglucose-5,6-ene. Hydride transfer from NADH to C6 of dTDP-4-ketoglucose-5,6-ene regenerates NAD(+) and produces the product dTDP-4-keto-6-deoxyglucose. The single-turnover reaction was quenched at various times on the millisecond scale with a mixture of 6 M guanidine hydrochloride and sodium borohydride, which stopped the reaction and reductively stabilized the intermediates and product. Quantitative MALDI-TOF MS analysis of the quenched samples allowed the simultaneous observation of the disappearance of substrate, transient appearance and disappearance of dTDP-hexopyranose-5,6-ene (the reductively stabilized dTDP-4-ketoglucose-5,6-ene), and the appearance of product. Kinetic modeling of the process allowed rate constants for most of the steps of the reaction of dTDP-glucose-d(7) to be evaluated. The transient formation and reaction of dTDP-4-ketoglucose could not be observed, because this intermediate did not accumulate to detectable concentrations.

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