Synthesis of 1-alkyl-3,4-dihydroisoquinoline derivatives and study of their effect on arterial pressure

A series of 1-alkyl-3,4-dihydroisoquinolines and the related 4-alkyl-1,2-dihydro-benzo[f]isoquinolines was synthesized using reactions of dialkylbenzylcarbinols and their naphthyl analogs with alkylcyanides. Experiments showed that 1-alkyl-6,7-dimethoxy-3,4-dihydroisoquinolines typically produce a hypotensive action, while the benzo-annelated structures usually exhibit a hypertensive effects. The most active compound decreases the arterial pressure in cats by 52 Torr and the effect lasts for about 4 hours. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 3, pp. 15–17, March, 2006.     

Antioxidant properties of extracts from the above-ground parts of Filipendula ulmaria

Extracts of the above-ground part of meadowsweet (Filipendula ulmaria L. Maxim.) demonstrate a pronounced antioxidant activity. It is established that 70% and 95% ethanol extracts contain the most active substances. Investigation of the chemical composition of the above-ground part of the plant and its 70% ethanol extract by means of qualitative reactions, thin-layer chromatography, and paper chromatography showed the presence of various phenolic compounds, including quercetin and its glycosides, dihydroquercetin, apigenin, rododendrol, esculetin, and m-hydroxybenzoic, salicylic, anisic, gallic, gentisic, ferulic, chlorogenic, and caffeic acids. __________ Translated From Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 12, Pp. 22–24, December, 2006.     

Increasing the efficiency of Monte Carlo cohort simulations with variance reduction techniques.

The authors discuss techniques for Monte Carlo (MC) cohort simulations that reduce the number of simulation replications required to achieve a given degree of precision for various output measures. Known as variance reduction techniques, they are often used in industrial engineering and operations research models, but they are seldom used in medical models. However, most MC cohort simulations are well suited to the implementation of these techniques. The authors discuss the cost of implementation versus the benefit of reduced replications.     

Light absorbing properties of indocyanine green (ICG) in solution and after adsorption to the retinal surface — an ex-vivo approach

BACKGROUND: To evaluate potential differences in light absorbing properties and stability of indocyanine green (ICG) adsorbed to the retinal surface and of ICG dissolved in water and balanced salt solution. METHODS: The retina of four human donor eyes was prepared by removing the vitreous from the retinal surface. The inner surface of the specimen was covered with two to three drops of a 0.05% or 0.15% ICG solution respectively. After 1 min, the dye was removed by careful irrigation using BSS plus. The retinal specimens were then investigated by diffuse reflection spectroscopy (UV/VIS/NIR Spectrometer Lambda 900/Perkin Elmer equipped with a PELA-1020 integrating sphere accessory) and their absorption evaluated by the Kubelka-Munk function. To control the sensitivity of the setting, diffuse reflectance spectra of ICG adsorbed to a cellulose membrane and Al(2)O(3) were measured. For comparison, absorption spectra of ICG dissolved in water and BSS plus solution were measured in relation to ICG concentration and time using an UV/VIS/NIR Spectrometer Lambda 900/Perkin Elmer. RESULTS: On the retinal surface, absorption spectra exhibited a steep increase of absorption beginning at 620 nm, with a maximum at 736 nm (0.05%) and a shoulder at 745 (0.15%) and a second maximum at approximately 800 nm for both concentrations. Repeated measurement of the retinal surface 13 days after the ICG exposure revealed no changes in the position of the maxima as compared to the initial measurements. Light absorbing properties of ICG on cellulose or Al(2)O(3) are similar to those seen on the retinal surface with respect to the pattern and location of absorption maxima. In contrast, ICG dissolved in water or BSS plus disclosed variations in absorption characteristics depending on dye concentration, solute and time of measurement. CONCLUSIONS: Absorption characteristics and stability of ICG bound to the retinal surface could be of relevance when investigating potential pathomechanisms of ICG related toxicity, which might be related not only to intraoperative but also to postoperative light exposure of patients after intravitreal use of ICG.     

Outcomes of low-vision services using optometric and multidisciplinary approaches: a non-randomized comparison

Consecutive patients (n = 215) who were referred to optometric (55%) or multidisciplinary (45%) low-vision services and above 50 years of age were recruited from four hospitals in the Netherlands. They completed two vision-related quality of life questionnaires, the Vision Quality of Life Core Measure (VCM1) and the Low Vision Quality of Life Questionnaire (LVQOL), before their first visit with low-vision services and 1 year later. At follow-up, patients referred to multidisciplinary low-vision services had lower scores on the mobility subscale of the LVQOL than patients referred to optometric low-vision services [5.3 points; 95% confidence interval (CI): 0.2-10.5]. Paired sample t-tests for the two groups of patients taken together show improvement for the VCM1 (3.1 points; 95% CI: 0.6-5.6) and deterioration for the basic aspects of vision (3.5 points; 95% CI: 1.1-5.9) and the mobility (6.6 points; 95% CI: 3.7-9.5) subscales of the LVQOL. In conclusion, people referred to optometric services showed less deterioration in mobility than those referred to multidisciplinary services. No differences were observed for any of the other subscales of the LVQOL and the VCM1. Future research in this field should include randomized controlled designs comparing low-vision services with no treatment or placebo.