Gerstmann's syndrome following an acute herpes simplex encephalitis

The authors present a rare clinical case of a woman who developed Gerstmann's syndrome following an acute Herpes simplex viral encephalitis. Clinical observation and laboratory evaluation were performed during the acute phase of the disease. After that the follow-up continued for one-year period. The localization of the pathologic process was determined by computerized tomography, conducted periodically. The characteristics of the clinical picture are interpreted in the context of the contemporary concepts of the topical diagnosis of Gerstmann's syndrome. The possibility of a sudden onset of acute Herpes simplex viral encephalitis without a preceding febrile-intoxication syndrome is worth noting. Conclusions are drawn stressing the need of an early etiologic treatment and the importance of the rehabilitation activities during the convalescence period.     

Creation of progressive technology for production of lubricating oils

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, pp. 17–20, May, 1990.     

Ambient Pressure Superconductivity in к-(BEDT-TTF)2Cu[N(CN)2]Cl Single Crystals

Single crystals of the к-(BEDT-TTF)₂Cu[N(CN)₂]Cl radical cation salt possessing metallic properties and showing a superconducting transition with Tc = 11.5 K at ambient pressure were first prepared.     

Three-Dimensional Numerical Simulation of the Development of Instability of a Contact Boundary of Colliding Metal Plates within the Gas-Dynamic Approximation

High Temperature - The development of the initial stage of instability of a contact boundary of colliding metal plates has been numerically simulated. The mathematical model is based on the Euler...     

Cytotoxic Potential of a-Azepano- and 3-Amino-3,4-SeCo-Triterpenoids

Semi-synthetic triterpenoids, holding an amino substituted seven-membered A-ring (azepano-ring), which could be synthesized from triterpenic oximes through a Beckmann type rearrangement followed by a reduction of lactame fragment, are considered to be novel promising agents exhibiting anti-microbial, alpha-glucosidase, and butyrylcholinesterase inhibitory activities. In this study, in an attempt to develop new antitumor candidates, a series of A-ring azepano- and 3-amino-3,4-seco-derivatives of betulin, oleanolic, ursolic, and glycyrrhetinic acids were evaluated for their cytotoxic activity against five human cancer cell lines and non-malignant mouse fibroblasts by means of a colorimetric sulforhodamine assay. Azepanoallobetulinic acid amide derivative 11 was the most cytotoxic compound of this series but showed little selectivity between the different human tumor cell lines. Flow cytometry experiments showed compound 11 to act mainly by apoptosis (44.3%) and late apoptosis (21.4%). The compounds were further screened at the National Cancer Institute towards a panel of 60 cancer cell lines. It was found that compounds 3, 4, 7, 8, 9, 11, 15, 16, 19, and 20 showed growth inhibitory (GI₅₀) against the most sensitive cell lines at submicromolar concentrations (0.20–0.94 μM), and their cytotoxic activity (LC₅₀) was also high (1–6 μM). Derivatives 3, 8, 11, 15, and 16 demonstrated a certain selectivity profile at GI₅₀ level from 5.16 to 9.56 towards K-562, CCRF-CEM, HL-60(TB), and RPMI-8226 (Leukemia), HT29 (Colon cancer), and OVCAR-4 (Ovarian cancer) cell lines. Selectivity indexes of azepanoerythrodiol 3 at TGI level ranged from 5.93 (CNS cancer cell lines SF-539, SNB-19 and SNB-75) to 14.89 for HCT-116 (colon cancer) with SI 9.56 at GI₅₀ level for the leukemia cell line K-562. The present study highlighted the importance of A-azepano-ring in the triterpenic core for the development of novel antitumor agents, and a future aim to increase the selectivity profile will thus lie in the area of modifications of azepano-triterpenic acids at their carboxyl group.     

Properties of porous cast charges based on mixtures of ammonium nitrate and carbamide

The explosive and physicochemical properties of porous mixtures based on ammonium nitrate, carbamide, and aluminum powder are considered. A melting curve for the ammonium nitrate/carbamide system is plotted using differential scanning calorimetry. The critical detonation diameter is obtained for a charge density of 0.6–0.7 g/cm³. The dependence of the charge density on the degree of filling of the mold with the melt is determined. Detonation velocity is measured for various densities. An explanation of the difference between the experimental and calculated values is proposed.     

Novel A-Ring Chalcone Derivatives of Oleanolic and Ursolic Amides with Anti-Proliferative Effect Mediated through ROS-Triggered Apoptosis

A series of A-ring modified oleanolic and ursolic acid derivatives including C28 amides (3-oxo-C2-nicotinoylidene/furfurylidene, 3β-hydroxy-C2-nicotinoylidene, 3β-nicotinoyloxy-, 2-cyano-3,4-seco-4(23)-ene, indolo-, lactame and azepane) were synthesized and screened for their cytotoxic activity against the NCI-60 cancer cell line panel. The results of the first assay of thirty-two tested compounds showed that eleven derivatives exhibited cytotoxicity against cancer cells, and six of them were selected for complete dose–response studies. A systematic study of local SARs has been carried out by comparative analysis of potency distributions and similarity relationships among the synthesized compounds using network-like similarity graphs. Among the oleanane type triterpenoids, C2-[4-pyridinylidene]-oleanonic C28-morpholinyl amide exhibited sub-micromolar potencies against 15 different tumor cell lines and revealed particular selectivity for non-small cell lung cancer (HOP-92) with a GI₅₀ value of 0.0347 μM. On the other hand, superior results were observed for C2-[3-pyridinylidene]-ursonic N-methyl-piperazinyl amide 29, which exhibited a broad-spectrum inhibition activity with GI₅₀ < 1 μM against 33 tumor cell lines and <2 μM against all 60 cell lines. This compound has been further evaluated for cell cycle analysis to decipher the mechanism of action. The data indicate that compound 29 could exhibit both cytostatic and cytotoxic activity, depending on the cell line evaluated. The cytostatic activity appears to be determined by induction of the cell cycle arrest at the S (MCF-7, SH-SY5Y cells) or G₀/G₁ phases (A549 cells), whereas cytotoxicity of the compound against normal cells is nonspecific and arises from apoptosis without significant alterations in cell cycle distribution (HEK293 cells). Our results suggest that the antiproliferative effect of compound 29 is mediated through ROS-triggered apoptosis that involves mitochondrial membrane potential depolarization and caspase activation.     

Study of the Spatial and Current Dynamics of Optical Loss in Semiconductor Laser Heterostructures by Optical Probing

Semiconductors - The spatial and temporal dynamics of the optical loss and carrier density in the heterostructure of a semiconductor laser with a segmented contact are studied using an optical...