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Abstract— We have developed an alternative method for the synthesis of an analog of natural retinal, which contains the p-fluorophenyl fragment instead of the trimethylcyclohexene ring. The proposed scheme for the synthesis of the target all-E-isomer of the target retinoid consists of using C5-phosphonate that contains the terminal nitrile group under Horner–Emmons reaction conditions. It has been shown that this scheme is more efficient and provides a higher total yield of the target product than the previously described variant. The procedure has been developed for the preparation of an analog of microbial proteorhodopsin ESRh from Exiguobacterium sibiricum, which contains a modified chromophore. It has been found that, as in the case of bacterioopsin from Halobacterium salinarum, the replacement of the trimethylcyclohexene ring in the natural chromophore by the p-fluorophenyl fragment does not prevent the formation of the artificial pigment F-Phe-ESRh from proteorhodopsin ESRh, which preserves the cycle of photochemical reactions. Certain differences have been found between the properties of native recombinant ESRh and its analog F-Phe-ESRh including a shift in the absorption maximum to the short-wavelength region, the formation of M intermediate at lower pH values, the presence of “long-lived M,” and a general slowdown in the photocycle. The reduced stability of the resulting proteorhodopsin analog F-Phe-ESRh to prolonged exposure to visible light has been also demonstrated.

The article deals with the current state of mineral and raw hydrocarbon base of Ukraine. The main promising directions of geological exploration for oil and gas are identified and determined: in reef-carbonate complexes, deep-seated petroliferous complexes, crystalline basement, non-anticlinal traps in sandy bodies, non-traditional HC sources.

Cardiac involvement in sarcoidosis is considered quite rare, but it can cause the first significant disease manifestations and patient’s death. Timely disease detection improves the effectiveness of treatment and prognosis. The article presents modern approaches to the diagnosis and management of patients with cardiac sarcoidosisusing clinical case of a patient hospitalized by ambulance with a first revealed symptomatic third-degree atrioventricular block. We described methods of examining this patient, as well as difficulties in differential diagnosis.

Guidelines and principles for the development of new labels and probes for bionanophotonics, methods for their preparation, and labeling procedures for various targets are briefly discussed.

This paper addresses a review of platinum-based hydrosilylation catalysts. The main field of application of these catalysts is the curing of silicone polymers. Since the 1960s, this area has developed rapidly in connection with the emergence of new polymer compositions and new areas of application. Here we describe general mechanisms of the catalyst activity and the structural effects of the ligands on activity and stability of the catalysts together with the methods for their synthesis.

The effect of Buchwald-type ligands on the platinum catalyzed hydrosilylation of vinyl-terminated polydimethylsiloxane has been studied by differential scanning calorimetry of platinum catalyst-containing silicone compositions. Dialkyl(biphenyl-2-yl)phosphines bearing bulky substituents at phosphorus atom are efficient inhibitors of the catalytic hydrosilylation process allowing one to increase the pot-life of silicone composition and to prevent the decomposition of the Pt-based catalyst.

The purpose of the study was to carry out a retrospective analysis of alterations in regional oxygenation (rSO2) of the brain at all stages of carotid endarterectomy (CEA) in order to detect predictors of ischaemia and hyperperfusion of the brain.In a total of 169 patients during CEA under general anaesthesia we registered rSO2 after induction of narcosis, prior to carotid artery cross-clamping, at 2 minutes and each 10 minutes after cross-clamping, before re-establishing blood flow, at 2 and 5 minutes thereafter, and finally at the end of the operation. We evaluated the baseline parameters and intraoperative alterations in regional oxygenation depending on clinical and instrumental data. We also carried out a multivariate regression analysis in order to reveal significant risk factors for ischaemia and hyperperfusion. We analysed the ROC curves in order to determine the threshold value of a decrease and increase of rSO2 in ischaemia and hyperperfusion of the brain.After the multivariate analysis, an independent predictor turned out to be grade III arterial hypertension (OR 9.5, 95% CI: 1.1-82.7). It was revealed that the most significant predictor of the development of hyperperfusion syndrome was the absolute increase in rSO2 after re-establishing blood flow by more than 11.3. Sensitivity, specificity, positive and negative prognostic value of the parameter revealed amounted to 87.4, 83, 35 and 98.4%, respectively.The multivariate analysis performed demonstrated that only long-standing grade III arterial hypertension was a significant risk factor for the development of hyperperfusion syndrome after CEA. In our study, the most accurate parameter for the Fore-Sight oximeter was the maximum increase of the absolute value of rSO2 after re-establishing blood flow above 11.3 Cerebral oximetry is a non-invasive, simple to use and interpreter method making it possible to evaluate not only ischaemia but hyperperfusion of the brain during CEA and in the early postoperative period.

The aim: to conduct retrospective study of cerebral regional oxygen saturation (rSO2) at all stages of carotid endarterectomy (CEA) to define ischemia and cerebral hyperperfusion predictors. Material and Methods ― rSO2 were registered in 169 patients under general anesthesia after induction, before carotid artery clamping, 2 minutes after and each 10 minutes after clamping, before, 2 and 5 minutes after reperfusion and at the end of the operation. We estimated baseline values and intraoperative changes of rSO2 in terms of clinical and instrumental findings. Logistic regression analysis was aimed to define significant risk predictors of cerebral ischemia and hyperperfusion and ROC-curve analysis – to set a cut-off point of rSO2 reduction and elevation. Results ― Arterial hypertension III grade (HR 9.5%; CI 95%: 1.1-82.7) appeared to be an independent predictor according to the results of multivariate analysis. It was revealed that the most significant predictor of hyperperfusion syndrome is absolute increase of rSO2 after reperfusion by more than 11.3. Sensitivity, specificity, positive and negative predicative value of the defined parameter were 87.4%, 83%, 35% and 98.4% respectively. Conclusion ― The conducted multivariate analysis demonstrated that only long-term arterial hypertension is a significant risk factor for hyperperfusion syndrome development after CEA. In our study the most accurate parameter for Fore-Sight oximeter is maximum value of absolute increase in rSO2 after reperfusion by more than 11.3. Cerebral oximetry is a non-invasive method which is easy to use and interpret and enables to estimate both ischemia and cerebral hyperperfusion during CEA and in the early postoperative period.

A number of photochromic markers, viz., spirobenzopyrans containing one or two active carboxy groups attached directly or through a spacer, as well as their model derivatives, were synthesized. The obtained compounds were characterized by instrumental methods of analysis. Spectrokinetic methods were used to study the behavior of the spirobenzopyran markers and the model derivatives in solutions in EtOH and toluene.

The purpose of the work was to improve the treatment results for patients with complicated pelvic injury using differentiated application of transosseous and internal osteosynthesis. Retrospective analysis of treatment results is presented for 52 patients with vertically unstable pelvic ring injuries and concomitant abdominal injuries. Clinical cases demonstrate the variants of clinical decision depending on the type of injury, degree of pelvic ring instability, pattern of concomitant abdominal injuries. Protocol of patient management in such injuries is suggested.

The closed injury of chest with the breaks of edges is the vital problem of traumatology, anesthesiology and resuscitation For the change to conservative treatment with the aid of mechanical ventilation of lungs today come the methods of surgical fixation with the closed injury of chest. The conducted investigation showed the clinical and economic expediency of introducing the method of active surgical tactics.

A method for synthesizing a photochromic ligand and using it as a structural element in a new nanodimensional hybrid construction in which CdSe quantum dots are covalently bonded to a spiropyran molecule has been proposed. Such a hybrid construction makes it possible to reversibly control the system fluorescence using a change in spiropyran ligand structure induced by light with different wavelengths (a reversible conversion from a colorless closed form into a colored merocyanine form). The possibilities for using this type of hybrid material for photocontrollable devices in nanophotonics are discussed.

In the present review, we summarize our recent studies on the synthesis and spectral–kinetic parameters of photochromic retinals based on spiropyrans, diarylethenes, and a fulgimide and the use of these compounds for the preparation of artificial analogs of natural bacteriorhodopsin.

Two bioisosteric analogs, 5-phenyl-3-(3-pyridyl)isoxazole and 5-phenyl-3-(3-pyridyl)-1,2,4-oxadiazole, were synthesized so as to compare their antiaggregatory activities, to determine a pharmacologically active fragment in molecules of this type, and to explore the mechanisms of action of potential antiag-gregatory compounds belonging to the class of 3,5-substituted isoxazoles. Antiaggregatory activities of these compounds were studied in vitro using three aggregation inducers, such as arachidonic acid, adenosine diphosphate, and adrenaline. It was shown that 5-phenyl-3-(3-pyridyl)-1,2,4-oxadiazole and 5-phenyl-3-(3-pyridyl)isoxazole completely suppressed platelet aggregation induced by arachidonic acid and the second wave of platelet aggregation induced by adrenaline or adenosine diphosphate. The antiaggregatory activity of substituted isoxasole was 1.1–1.5 times higher than that of substituted oxadiazole. In contrast to the isoxazole analog, 5-phenyl-3-(3-pyridyl)-1,2,4-oxadiazole in concentrations of 300–400 μM partially suppressed the first wave of aggregation induced by adenosine diphosphate. It was demonstrated that both compounds were not thrombin inhibitors in vitro at concentrations up to 250 μM. Thus, introduction of a nitrogen atom into the C4-position of the isoxazole ring changes the molecule properties. It suggests that the pharmacophoric fragment of the molecule should be the whole isoxazole or 1,2,4-oxadiazole ring but not a part of the ring as was supposed previously.

The synthesis of retinal analogue series that contain a spyropyran moiety instead of a trimethylcyclohexene ring was proposed. The process of the retinal analogue interaction with bacterioopsin from apomembranes of Halobacterium salinarum and the spectral properties of the newly formed pigments were studied. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2008, vol. 34, no. 2; see also http://www.maik.ru.

A high diversity of tabulate corals in Eifelian deposits of the Syv“yu River basin (Subpolar Urals) is reported for the first time. Most of the corals are represented by colonies of syringoporids. Five new species Syringopora parva sp. nov., S. insueta sp. nov., S. indecora sp. nov., Tetraporinus syvjuensis sp. nov., and Armalites serotinus sp. nov. are described.

The reaction of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with dimethyl sulfate leads to mixtures of N-mono- and N,N-dimethylnitrotriazolium compounds and products of the subsequent conversion of the latter, namely, N,N-dimethyl-1,2,4-triazol-5-ones.

Alkylation of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with dialkyl sulfates or alkyl halides in the presence of alkali proceeds with a low selectivity for the alkylating agent with the formation of two regioisomers at the N(1) and N(2) atoms of the heterocycle. Depending on the reaction conditions the proportion of the N(2) isomer was 14.6-33.8%.

Spectral properties of new crowned spiropyrans and their cationic complexes are described.

The spectral properties of new crowned retinal analogs and their bacteriorhodopsin complexes are described.

An effective synthetic approach to the preparation of a new crown-ether vinylogs involving the Horner–Emmons olefination of carbonyl precursors with the use of C2- and C5-phosphonates was proposed. The effects of the conjugation chain length and the nature of the terminal polar functions in the phosphonate reagent on the yield and process stereoselectivity were discussed.

A method for synthesis of retinal analogs labeled with electron-density groups is suggested. The interaction of these polyene compounds with bacterioopsin in apomembrane of Halobacterium salinarum was tested. A retinal analog containing a crown-ether receptor group is able to interact readily with bacterioopsin giving rise to rapid formation of a pigment with absorption maximum at 460 nm. This pigment is capable of undergoing cyclic photoconversion. The crown-bacteriorhodopsin photocycle is extremely slow and its quantum efficiency is very low (∼3% of that in native bacteriorhodopsin). This photocycle includes an M-like intermediate with a differential absorption maximum at 380 nm. A retinal analog in which the β-ionone ring is replaced by ferrocene moiety forms a stable chromoprotein with the main absorption band at 483 nm and a shoulder near 590-610 nm.

We described two synthetic routes for preparation of new crown ether derivatives of polyenals, containing variable length of the conjugation chain.