Synthesis and antitumor activity of 5-(5′,6′-benzocoumaro-3′-yl)methylaminouracil hydrobromide and its liposomal medicinal form

The antitumor activity of 5-(5′,6′-benzocoumaro-3′-yl)methylaminouracil (BCMU) and its liposomal medicinal form was studied in comparison to 5-fluorouracil (5-FU), a well-known antitumor drug widely used in oncological practice. The half-lethal dose of BCMU is 14.8 ± 4.2 mg/kg, while the optimum effective dose of the drug is 6 mg/kg. In this dose, BCMU combines low toxicity with significant antitumor activity, which is manifested by increased tumor growth inhibition (TGI) at a 19% increase in the lifetime (LT) of experimental animals. The antitumor activity of the liposomal form of BCMU is quantitatively and qualitatively superior to that of the nonmodified compound and 5-FU, which is manifested by the most pronounced TGI value and by a significant LT increase. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 6, pp. 6–7, June, 2006.     

The incidence of myopia in the children of myopic parents and the outlook for the primary prevention of this type of refraction

The paper analyses results after investigation of free selection of families, parents myopia selected by signs and a definite minimum age of their first-order offsprings, including 108 matrimonial couples with the total number of 209 children. It was found that myopia is a hereditary sign manifesting itself in children at the age above 15 years and more in 90% of families of the first-order offsprings of the couples in whom one of the parents has this kind of refraction, and in 100% of families in whom both parents suffer from this kind of refraction. The incidence of myopic children in families in whom one or both parents have myopia ranges from 68% to 86%, and depends on the type of refraction.     

Hormonal profiles and follicular growth in cycles with imminent ovarian hyperstimulation

Ovarian hyperstimulation syndrome is a common and serious complication of human menopausal gonadotrophin/human chorionic gonadotrophin treatment. We evaluated the changes in the pituitary and ovarian hormone profiles and ultrasonographic follicular regression in 12 patients in whom human menopausal gonadotrophin was discontinued due to 'imminent' ovarian hyperstimulation. Following discontinuation, three distinct periods were observed: (i) days 1-2, the levels of oestradiol, testosterone and prolactin, and the total number of follicles continued to rise; (ii) days 3-6, the levels of oestradiol, testosterone and prolactin declined sharply and the total number of follicles was reduced significantly, while the large and medium sized follicles continued to increase. Levels of follicle-stimulating hormone and luteinizing hormone gradually declined to reach their lowest levels by days 5-6 and then increased. (iii) Thereafter the number of follicles and steroid output declined to early follicular phase levels. We conclude that discontinuation of human menopausal gonadotrophin and withholding human chorionic gonadotrophin in cycles with laboratory signs of 'imminent' ovarian hyperstimulation syndrome, allows regression of the ovarian ultrasonographic finding and prevents the development of clinical symptoms. However, if rescue of the cycle is attempted, human chorionic gonadotrophin should be given during the first 4 days after discontinuation of stimulation.     

In vivo 23Na NMR studies of myotonic dystrophy

Myotonic dystrophy is an inherited multi-system disease. Its pathophysiology leading to muscle malfunction and damage is not well understood. ²³Na NMR spectroscopy was applied here for an in vivo comparative study of the calf muscles of 7 myotonic dystrophy patients at various stages of the disease and 11 healthy volunteers. Both the total sodium content, expressed as the ratio of the ²³Na and ¹H water signals, and the fast transverse relaxation time, T₂₁, determined from the triple quantum-filtered spectra, increased in correlation with the severity of the disease. The results demonstrate that ²³Na NMR enables the quantitation of myotonic dystrophy progression.     

In vivo 31P NMR studies of paraplegics' muscles activated by functional electrical stimulation

The bioenergetics of paralyzed muscles of spastic paraplegic patients under functional electrical stimulation (FES) was studied in vivo using ³¹P NMR. The protocol included rest, 3 min of induced tetanic isometric contraction through surface electrodes and 40 min of recovery. The continuous stimulation, the force recording and the ³¹P NMR measurements were sampled simultaneously inside the whole body imager. Normal values were found for the phosphorous metabolite ratios at rest. During contraction, prominent changes were detected including: a) accumulation of inorganic phosphate (P) accompanied by an unusually strong signal in the phosphomonoester (PME) region, b) phosphocreatine (PCr) decline, and c) a decrease in the intracellular pH. In the following recovery period the physiological state of the muscle was monitored and quantitated by ³¹P NMR. No metabolic and mechanical irreversible damage was detected in the paraplegics' muscles activated by FES under our experimental conditions.     

Interhemispheric sleep EEG asymmetry in the rat is enhanced by sleep deprivation

Vigilance state-related topographic variations of electroencephalographic (EEG) activity have been reported in humans and animals. To investigate their possible functional significance, the cortical EEG of the rat was recorded from frontal and parietal derivations in both hemispheres. Records were obtained for a 24-h baseline day, 6-h sleep deprivation (SD), and subsequent 18-h recovery. During the baseline 12-h light period, the main sleep period of the rat, low-frequency (<7.0 Hz) power in the non-rapid eye-movement (NREM) sleep EEG declined progressively. Left-hemispheric predominance of low-frequency power at the parietal derivations was observed at the beginning of the light period when sleep pressure is high due to preceding spontaneous waking. The left-hemispheric dominance changed to a right-hemispheric dominance in the course of the 12-h rest-phase when sleep pressure dissipated. During recovery from SD, both low-frequency power and parietal left-hemispheric predominance were enhanced. The increase in low-frequency power in NREM sleep observed after SD at the frontal site was larger than at the parietal site. However, frontally no interhemispheric differences were present. In REM sleep, power in the theta band (5.25-8.0 Hz) exhibited a right-hemispheric predominance. In contrast to NREM sleep, the hemispheric asymmetry showed no trend during baseline and was not affected by SD. Use-dependent local changes may underlie the regional differences in the low-frequency NREM sleep EEG within and between hemispheres. The different interhemispheric asymmetries in NREM and REM sleep suggest that the two sleep states may subserve different functions in the brain.     

Analysis of gabapentin in serum and plasma by solid-phase extraction and gas chromatography-mass spectrometry for therapeutic drug monitoring

A simple method for the determination of gabapentin (Neurontin) is described. The method uses solid-phase extraction by disk column and derivatization followed by gas chromatographic-mass spectrometric analysis. The single-step derivatization with MTBSTFA produces a t-BDMS derivative of both the carboxylic and amine moieties of the molecule. Each step of the procedure was optimized to assure reliable performance of the method. The assay limit of detection was 0.1 microg/mL with a linear range from 1.0 to 35 microg/mL. Within-run (n = 3) and between-run (n = 40) coefficients of variation were less than 8.2 and 15.9%, respectively. The method has proven reliable in routine production for more than a year, producing clean chromatography with unique ion fragments, consistent ion mass ratios, and no interferences. Statistical analysis of the gabapentin concentrations measured in 1020 random specimens over a 2-month period showed a mean concentration of 6.07 microg/mL with a standard deviation of 5.28.