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A challenging problem of modern surface-enhanced Raman spectroscopy (SERS) analysis is related to the design of new composite materials with bioprotective properties providing either a reproducible signal of small quantities or intactness of protein molecules. A new way of modification of silver-based SERS-active substrates with polymer materials is proposed here to achieve large enhancement factors of SERS signals for hemoproteins. It is found that the factors grow in the order: chitosan < bare silver < alginic acid sodium salt ≤ polyacrylic acid. This demonstrates an important role of the polymer origin and its charge state in the retention of protein on the sensor surface and protecting the proteins from silver ions of the nanostructured layer in the sake of future medical diagnostics. [ABSTRACT FROM AUTHOR]

Published data describing the current status and prospects for the development of clinical diagnostics of a number of neurodegenerative and neuroendocrine diseases associated with neurotransmitter balance disorders in a human body are generalized, systematized, and assessed in the review. Characteristics, advantages, and limitations of neuroimaging techniques and different diagnostic methods based on measuring concentrations of protein markers, catecholamines, and their metabolites are discussed. Prospects of the application of optical methods, such as fluorimetry and surface-enhanced Raman spectroscopy, to the development of sensor systems for the diagnosis of these diseases by the concentration of catecholamines and their metabolites in biological fluids are demonstrated. [ABSTRACT FROM AUTHOR]

The kinetics of H desorption from the surface of a copper-platinum catalyst deposited on silica gel ([1 wt % Pt + 0.15 wt % Cu]/SiO) and the kinetics of CH dehydrogenation were studied. The effects of copper introduction in a platinum catalyst on the structural characteristics of platinum particles, the composition of their surface, and the effects of plasmochemical treatments on these parameters were studied by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The metal-H atom bond energies ( E) and the catalytic activity were found to increase in the presence of Cu. This was explained by the formation of new hydrogen adsorption centers (due to the Cu adatoms) and catalytic centers composed of Cu adatoms and carbon atoms. The mean diameter of Pt particles ( D) increased twofold. The microstresses (ɛ) in the particles increased after the catalyst was treated with glow discharge plasma in Ar and O and with high-frequency plasma in H (HF-H). The observed changes in the bond energy E and kinetic parameters were explained by the increase in microstresses in Pt particles. [ABSTRACT FROM AUTHOR]

Metal-intermetallic laminated composites are fabricated upon reaction sintering of titanium and aluminum foils of various thicknesses. The mechanical properties of the composites with various metallic and intermetallic component contents are estimated using static and dynamic tests. The mechanical properties of the laminated composites are found to be anisotropic during static and dynamic loading. [ABSTRACT FROM AUTHOR]

We studied the interaction between O,O-diethyl-S-[(N-acyl-N-alkoxycarbonylalkyl)aminomethyl]thiophosphates and mammalian cholinesterases as well as esterases from insect tissue extracts by kinetic methods and disc electrophoresis. The coefficients of combined effect of these compounds or their dithioanalogs with permethrin were determined. The obtained data suggest that the synergistic effect on the common cockroaches and houseflies is chiefly due to carboxylesterase inhibition by monothioderivatives and monooxygenase suppression by dithioderivatives, respectively. [ABSTRACT FROM AUTHOR]

We studied the anticholinesterase and anticarboxylesterase effects of 1,3,2-oxazaphosphorynane derivatives and certain cyclic and acyclic analogs on the two enzymes of homoiotherms (ACE from human erythrocytes and BuCE from horse serum) as well as the enzymes from insect tissues (the nerve cord of the American cockroach and the cephalic region of the domestic fly). The differences in in vitro antiesterase activity of cyclic thionic and the corresponding oxo derivatives of phosphorinane were revealed. The mechanism of the esterase active center phosphorylation not only splitting off the outgoing group ( in vivo) but also opening the cycle by P–O bond ( in vitro and possibly in vivo) is usually proposed to explain the higher inhibiting activity of the thionic compounds compared to the oxonic ones. The possible involvement of this phosphorylation mechanism in the synergistic activity of the studied compounds is discussed. [ABSTRACT FROM AUTHOR]

A series of S-[ N-acyl- N-(alkoxycarbonylalkyl)aminomethyl] O,O-dialkyl phosphorothioates and -dithioates were prepared by the reactions of the corresponding alkali salts of dialkyl phosphorothioates or dialkyl phosphorodithioates with esters of N-acyl- N-(chloromethyl)glycine or N-acyl- N-(chloromethyl)-β-alanine and by the reactions of dialkylphosphorothioic or dialkylphosphorodithioic acids with N-acylated amino acids or their esters and paraformaldehyde in the presence of gaseous HCl. Some of the resulting compounds proved to be active permethrine synergists. [ABSTRACT FROM AUTHOR]

Methods were developed for the synthesis of 2-butylthio-2-oxo-1,3,2-oxazaphosphorinane, 2-butylthio-2-thioxo-1,3,2-dioxaphosphorinane, and 2-butylthio-2-thioxo-1,3,2-diazaphosphorinane, as well as of acyclic S-butyl O-ethyl (diethylamido)phosphorothioates and-dithioates and S-butyl bis(diethylamido)phosphorodithioate. These compounds can serve as models of possible metabolites of cyclic compounds. Based on the data obtained in studies of the antiesterase activity of the resulting compounds and their synergistic activity in mixtures with permethrine, a possible mechanism of in vitro and in vivo biological action of diheteraphosphorinanes was proposed. [ABSTRACT FROM AUTHOR]

Methods for the synthesis of 2-aryloxy(arylthio)- and 2-alkoxy(alkylthio)-2-thio(oxo)-1,3,2-oxazaphosphorinanes and their N-substituted derivatives based on the reactions of the corresponding dichlorophosphates, dichlorothio-, and dithiophosphates with 3-aminopropan-1-ol or its substituted derivatives in the presence of EtN or aqueous alkali under phase transfer catalysis conditions, as well as by the reaction of the tetramethylammonium salt of 2-hydroxy-2-thio-1,3,2-oxazaphosphorinane with alkyl- and acyl halides, by that of 2-chloro-2-thio-1,3,2-oxazaphosphorinane with sodium thiolates, and by other methods, were developed. The compounds obtained exhibit high nematocide activity but low toxicity for mammals. Some active synergists for permethrine were found among these compounds. [ABSTRACT FROM AUTHOR]

The content of low-molecular-weight components in blood serum was studied by tandem mass-spectrometry in pregnant women. Serum metabolic profiles of patients with a grave obstetrical history were detected. The most significant changes were observed for the concentrations of low-molecular-weight substances involved in glucogenesis and β-oxidation processes and in metabolic chains involving carbohydrates, carnitines, amino acids, and lipids. [ABSTRACT FROM AUTHOR]

An abstract of the research paper "Relationship Between Ultrasound and Dopplerometry in Labor and Fetal Hypoxia," by O.V. Eremina and colleagues is presented.

An abstract of the conference paper "Abnormal placentation-prospects of ultrasound diagnosis," by L. S. Ejova and colleagues is presented.

An abstract of the conference paper "Fetus-in-fetu-an ultrasound examination" by V. N. Demidov and colleagues is presented.