[Combined Approach for Management of the Chronic Heart Failure with Preserved Left Ventricular Ejection Fraction and Permanent Atrial Fibrillation: a Case Report].

The article described a clinical case of a patient with chronic heart failure (CHF) with preserved ejection fraction (CHF-PEF) and permanent normosystolic atrial fibrillation (AF). A 73 year-old man (body mass index, 26.4 kg /m2) with permanent normosystolic AF (duration, 10 years) was hospitalized for augmenting of CHF symptoms. The patient had NYHA II-III functional class CHF and a history of long-standing arterial hypertension. The patient received chronic therapy according to the effective guidelines (angiotensin receptor blockers, diuretics, beta-blockers, and new oral anticoagulants). Transthoracic echocardiography showed a normal ejection fraction (EF) (57 %), a moderate enlargement of the left atrium (48 mm), and moderate left ventricular (LV) hypertrophy. Radiofrequency catheter ablation (RFCA) of left atrial AF was performed. For preparation to the RFCA, the patient was administered propanorm two weeks prior to the procedure. Following external electrical cardioversion (ECV) after RFCA, sinus rhythm did not recover. The patient was prescribed amiodarone, and repeat ECV was performed in a month, which resulted in successful recovery of sinus rhythm. However, due to an increase in serum thyrotropic hormone, amiodaron was replaced with the sotalol therapy (240 mg/day). This resulted in development of symptomatic sinus bradycardia and AF relapse at 3 days after ECV. A dual-chamber cardioverter defibrillator was implanted to the patient; in another three months, repeat AF RFCA was performed with successful recovery of sinus rhythm. During the cardioverter testing for one year, the patient had one more AF episode, which was stopped by external ECV. Also, a 6-hour AF episode occurred at three months after the repeat RFCA. Symptoms of CHF disappeared by the 12th month. The combination therapy administered to the patient with normosystolic permanent AF and preserved EF, which included a pathogenetic therapy for CHF, antiarrhythmic drugs, implantation of a dual-chamber ECV, two sessions of AF RFCA, and repeat external ECVs, provided considerable improvement of CHF symptoms and stable sinus rhythm during a one-year follow-up. The return to sinus rhythm after 10 years of permanent AF necessitated changing the arrhythmia diagnosis to long-standing, persistent AF.

Local electronic nematicity in the two-dimensional one-band Hubbard model.

Nematicity is a well-known property of liquid crystals and has been recently discussed in the context of strongly interacting electrons. An electronic nematic phase has been seen in many experiments in certain strongly correlated materials, in particular, in the pseudogap phase generic to many hole-doped cuprate superconductors. Recent measurements in high Tc superconductors have shown that even if the lattice is perfectly rotationally symmetric, the ground state can still have strongly nematic local properties. Our study of the two-dimensional one-band Hubbard model provides strong support for the recent experimental results on local rotational C4 symmetry breaking. The variational cluster approach is used here to show the possibility of an electronic nematic state and the proximity of the underlying symmetry-breaking ground state within the Hubbard model. We identify this nematic phase in the overdoped region and show that the local nematicity decreases with increasing electron filling. Our results also indicate that strong Coulomb interaction may drive the nematic phase into a phase similar to the stripe structure. The calculated spin (magnetic) correlation function in momentum space shows the effects resulting from real-space nematicity.

Spin-charge separation and electron pairing instabilities in Hubbard nanoclusters.

Electron charge and spin pairing instabilities in various cluster geometries for attractive and repulsive electrons are studied exactly under variation of interaction strength, electron doping and temperature. The exact diagonalization, level crossing degeneracies, spin-charge separation and separate condensation of paired electron charge and opposite spins yield intriguing insights into the origin of magnetism, ferroelectricity and superconductivity seen in inhomogeneous bulk nanomaterials and various phenomena in cold fermionic atoms in optical lattices. Phase diagrams resemble a number of inhomogeneous, coherent and incoherent nanoscale phases found recently in high-T(c) cuprates, manganites and multiferroic nanomaterials probed by scanning tunneling microscopy. Separate condensation of electron charge and spin degrees at various crossover temperatures offers a new route for superconductivity, different from the BCS scenario. The calculated phase diagrams resemble a number of inhomogeneous paired phases, superconductivity, ferromagnetism and ferroelectricity found in Nb and Co nanoparticles. The phase separation and electron pairing, monitored by electron doping and magnetic field surprisingly resemble incoherent electron pairing in the family of doped high-T(c) cuprates, ruthenocuprates, iron pnictides and spontaneous ferroelectricity in multiferroic materials.

[Local skin blood flow in hypokinesis]. / Lokal'nyi kozhnyi krovotok v usloviiakh gipokinezii.

Functional indices of peripheral autonomic nervous system responsible for regulation of tissue circulation were studied with doppler laser-flowmetry in patients exposed to long-term hypokinesia. Valsalva test, orthostatic test, cold test, etc., have discovered shifts in the system regulating local skin blood flow. Compared to control, changes in the blood flow were considerable and its recovery went very slowly.

Simultaneous image acquisition utilizing hybrid body and phased array receiver coils.

In clinical MR imaging the design and selection of receiver coil is an important step in ensuring the highest image quality. Often this choice is based on selecting a receiver coil characterized by high spatial uniformity such as the body and head volume receiver coils or a surface coil (or array of coils) that provide high signal-to-noise ratio (SNR). In the past, it has been difficult to accomplish both high SNR and spatial uniformity as both coil types achieve one of these characteristics at the expense of the other. The purpose of this study was to achieve both high SNR and spatial uniformity through the simultaneous acquisition of the MR signal using the body and a surface coil array. Results indicate that this hybrid system can provide uniformity and SNR values comparable to those achieved by the body and surface coil arrays, respectively.

[Anesthesia in magnetic resonance tomography]. / Provedenie anestezii pri magnitno-rezonansnoi tomografii.

Sixty patients were anesthesized for MRI. Intravenous and/or intramuscular anesthesia with ketamine, diazepam, pipolphen (promethazine) was supplemented by aminazine (chlorpromazine) or tisercin for adult patients. Spontaneous respiration was maintained, which helped avoid problems with endotracheal intubation and assisted ventilation. The method is safe, economic, and its side effects are negligible. Main features of MRI and specific anesthesiological problems associated with this method are discussed.

Determination of appropriate RF blocking impedance for MRI surface coils and arrays.

Surface and phased array receiving coils in MRI typically require that RF excitation be accomplished using the body coil. This process requires that the receiving coils contain blocking circuitry to increase the overall circuit impedance during RF excitation and withstand the electromotive force induced by the applied electromagnetic field. The aim of this study was to determine the optimal impedance range required during RF excitation based on an assessment of image quality. The experimental results are fit by an exponential model and establish criteria that can be applied for general receiver coil design.

[GABA reuptake by rat brain slices in hypokinesia and under the influence of cinnarizine and flunarizine]. / Obratnyi zakhvat GAMK srezami golovnogo mozga krys v usloviiakh gipokinezii i pod vliianiem tsinnarizina i flunarizina.

Studies showed that 15-day restriction of motor activity inhibits the reuptake of GABA by sections of the rat brain cortex and hypothalamus. In prolonged intraperitoneal injection of 10 mg/kg cinnarizine in hyperkinesia, further inhibition of this process in hypothalamic sections is encountered on the 15th days. Flunarizin (1 mg/kg) administered in a like manner has no significant effect on GABA reuptake. A course of GABA injections in a dose of 5 mg/kg improves in rats with restricted motor activity the local blood flow in the frontal lobe of the brain.

Pharmacological activity of phenylpropanoids of the mistletoe, Viscum album L., host: Pyrus caucasica Fed.

Although a great number of compounds have been isolated from Viscum album (mistletoe, Viscaceae), none of them could be clearly shown to possess the established hypotensive, vasodilator, cardiotonic and antitumor activity of alcoholic preparations. In the course of our investigation of Armenian mistletoe Viscum album, host: Pyrus caucasica, which has been used in Armenian traditional medicine for the treatment of cardiovascular diseases and for stimulation of the immune system, four phenylpropanoid glycosides were isolated from EtOH-extract: coniferyl alcohol 4-O-ß-D-glucopyranoside (coniferin), syringenin 4-O-ß-D-glucopyranoside (syringin), and coniferylalcohol- and syringenin 4-O-ß-D-apiofuranosyl (1→2)-ß-D-glucopyranosides. The structures were established on the basis of the spectral and chemical data. All substances inhibited ADP-induced platelet aggregation, and the apiosyldiglycosides only inhibited leukotriene B4 release from TPA and calcium ionophore A-23187 stimulated human granulocytes. It is suggested that an antitumoral effect of ethanolic extract of Viscum album could be associated with the inhibition of protein kinase C (PKC).

Imaging characteristics of x-ray capillary optics in digital mammography.

Computed radiography (CR) has shown promise in digital mammographic screening due to its good low spatial frequency MTF and its relatively wide exposure latitude. The CR image format has not gained acceptance clinically because of reduced high spatial frequency resolution as compared to film-screen images. X-ray capillary optics, aligned between the breast and CR phosphor imaging plate, will capture primary x-ray photons almost exclusively. Due to the very small angle of acceptance, scattered photons angled more than about 1.6 x 10(-3) radians from primary trajectory will not be accepted at the capillary optic entrance. The virtual elimination of detected scatter means almost 100% of the possible primary contrast should be visible in the image. In addition, the image can be magnified without focal spot blurring. Effective resolution of CR images can be increased by a factor equal to that magnification. Clinical implementation of future capillary optics are expected to be either in the form of a large, stationary, post-patient optic that accepts primary from the entire breast or a fan-shaped optic that is scanned across the breast. Measurements of a test capillary optic showed a reduction of scatter fraction to 0.018. Images of a lucite contrast detail phantom revealed a corresponding increase in image contrast when compared to anti-scatter grid and no grid methods. Spectral transmission measurements using a high-purity germanium detector showed good primary transmission (45%-50%) in the mammographic energy range. The MTF measurements of both stationary and scanned capillary optics showed improvement at the 5% MTF level to 8.4 mm-1 for scanned optics and 9.2 mm-1 for stationary optics representing a 68% and 84% respective increase over the CR MTF without magnification or capillary optics.

[Cerebral blood flow and thrombocyte aggregation at different times of hypokinesia and their regulation by antiaggregants]. / Mozgovoi krovotok, agreguemost' trombotsitov v razlichnye sroki gipokinezii i ikh reguliatsiia antiagregantami.

Changes in local cerebral blood flow and in microcirculatory channels in the cortex of rat brain were studied in conditions of early and remote hypokinesia. The rheological parameters of blood were studied in patients which stayed in ber for a long time in traumatological hospitals. We showed that by the 60th day of hypokinesia and in conditions of active readaptation the disordered cerebral blood flow starts to stabilize and tendency to normalization of some parameters of the cerebral blood flow and microcirculatory channels become clearly seen. The study of the functional state of the platelets showed that prescription of antiaggregants along with physical training can prevent thromboembolic aggravations associated with hypokinesia.

[The cerebral blood circulation during hypokinesia under the influence of hypercapnia, hypotonia, GABA and neurosensory stimulation]. / Mozgovoe krovoobrashchenie v usloviiakh gipokinezii pod vliianiem giperkapnii, gipotonii, GAMK i neirosensornog razdrazheniia.

We studied the formation of vasomotor reflexes in hypokinesia and responses of the brain vessels to the action of GABA, hypotension, and hypercapnia. We found that the response of the brain vessels to GABA is delayed and the mechanisms which supported an adequate cerebral vasculation are distorted in hypotension. At the same time the disturbance of the reflectory reaction of the brain vessels in the course of forming the vasomotor reflexes and the absence of significant changes in response to GABA were noticed. The capability of GABA of inhibiting cerebral blood circulation arising in hypokinesia is shown.

Forced migrations as a social problem.

PIP: The size and characteristics of recent refugee migration in the former Soviet Union is assessed; the study concerns those fleeing from ecological disasters as well as from interethnic conflict. The problems of providing refugee assistance are discussed. This is a translation of a Russian article in "Migratsiia naseleniia", Moscow, Russia, Russian Academy of Sciences, 1992, pp. 61-82.^ieng

[Regulator mutants for the synthesis of a 2d purine nucleoside phosphorylase in Escherichia coli K-12. II. Mapping and study of the dominance of pndR mutations]. / Reguliatornye mutanty po sintezu vtoroi purinnukleozidfosforilazy u Escherichia coli K-12. Soobshchenie II. Kartirovanie i izuchenie dominantnosti mutatsii pndR.

The synthesis of a second purine nucleoside phosphorylase (PNPII) in the wild type strains of Escherichia coli K-12 is induced by xanthosine. Three types of pndR mutants were studied, which are altered in regulation of PNPII synthesis: 1) constitutive, 2) inducible by nucleosides of hypoxantine and adenine as much as by xanthosine and 3) defective in synthesis of PNPII. All pndR mutations are located in transductional crosses on 51 min of E. coli genetic map. The order of genes established is as follows: pndR-ptsH-cysA. Mutations of the first and second type are dominant, while pndR21 mutation of the third type is recessive to the pndR+ allele on F' episome. The data obtained support the suggestion that the product of pndR regulatory gene is an activator protein necessary for the expression of the PNPII structural gene.

[Regulatory mutants for the synthesis of a 2d purine nucleoside phosphorylase in Escherichia coli K-12. I. Synthesis inducers and the substrate specificity of purine nucleoside phosphorylase in pndR mutants]. / Reguliatornye mutanty po sintezu vtoroi purinnukleozidfosforilazy u Escherichia coli K-12. Soobshchenie I. Induktory sinteza i substratnaia spetsifichnost' purinnukleozidfosforilazy u mutantov pndR.

Restoration of the ability to catabolise the purine nucleosides in phenotypic revertants of Escherichia coli K-12 mutants defective in deoD encoded purine nucleoside phosphorylase (PNPase 1) is the result of regulatory pndR mutations for synthesis of a second purine nucleoside phosphorylase (PNPase 2). In pndR+ strains synthesis of PNPase 2 is induced by xanthosine; in pndR mutants catabolising all purine nucleosides synthesis of this enzyme is constitutive; in other pndR mutants only catabolising some of purine nucleosides, this catabolisible nucleosides, namely, deoxyinosine, deoxyadenosine as well as, in some cases, inosine and adenosine, act as inducers of PNPase 2 synthesis. In some pndR mutants with inducible PNPase 2, xanthosine is a stronger inducer, in others it is weaker, in comparison with pndR+ strains. In bacterial cells PNPase 2 catalyses the phosphorolytic cleavage of adenosine, inosine, deoxyinosine, guanosine, deoxyguanosine and xanthosine, though in crude extracts adenosine and deoxyadenosine phosphorylase activities of the enzyme are not expressed.

[Escherichia coli K-12 mutants assimilating adenine via a new metabolic pathway]. / Mutanty Escherichia coli K-12, usvaivaiushchie adenin po novomu metabolicheskomu puti.

Two pathways of adenine utilization are only known in Escherichia coli K-12: the conversion to adenosine monophosphate by adenine phosphoribosyltransferase (apt gene) and ribosylation to adenine nucleosides by purine nucleoside phosphorylase (deoD gene). The purine auxotrophs defective in synthesis of inosine monophosphate de novo (pur) and carrying apt and deoD mutations cannot satisfy their purine requirements by exogenously supplied adenine or adenosine. We have selected spontaneously secondary-site revertants (designated adu) of pur apt deoD mutants, by plating on adenine or adenosine as the sole purine source. The adu mutations frequency was 6-10(-7). The phenotypical suppression of adenine phosphoribosyltransferase and purine nucleoside phosphorylase deficiency by adu mutations is neither the consequence of apt + or deoD + reversions nor the result of appearance in mutant cells of any activity converting adenine to adenosine monophosphate or adenosine. Adenine utilization in adu mutants is not caused by constitutive synthesis or genetic modification of the substrate specificity of adenosine deaminase (add gene). The direct deamination of adenine to give hypoxanthine in extracts of adu2 mutant has been shown. The data obtained suggest the possibility of a new adenine deaminase activity to appear in E. coli by means of single mutations.

[Phenotypic manifestation of the pnd mutation, which promotes purine nucleoside cleavage by Escherichia coli K-12 cells, in the genome of strains defective in the metabolism of nucleic acid precursors]. / Fenotipicheskoe proiavlenie mutatsii pnd, sposobstvuiushchei rasshchepleniiu purinovykh nukleozidov kletkami Escherichia coli K-12 v genome shtammov, defektnykh po metabolizmu predshestvennikov nukleinovykh kislot.

Strains of Escherichia coli K-12 containing both pnd1 mutation, rendering bacteria capable to catabolize purine nucleosides without participation of purine nucleoside phosphorylase (pup gene), and mutations in several genes of purine metabolism or nucleosides catabolism have been constructed. The introduction of the deletion mutation in adenosine deaminase gene (add) into the pup pnd genome does not affect the ability of mutants to utilize adenosine and deoxyadenosine as the sole carbon and energy sources. Mutations affecting purine phosphoribosyltransferases (hpt and gpt) block the ability of pup pnd mutants to utilize hypoxanthine, guanine and their deoxyribonucleosides and also xanthine and xanthosine as the only purine source. A mutation in deoxyribomutase (drm) disturbs the ability of pnd mutants to use all purine ribo- and deoxy-ribonucleosides as carbon and energy sources, whereas a mutation in deoxyriboaldolase (dra) only disturbs utilization of deoxyribonucleosides. These data seem to indicate that the activity promoted by pnd mutations catalyzes the cell reaction of irreversible phosphorolytic cleavage of the N-glycoside bond of the purine nucleosides molecules: purine nucleoside + phosphate leads to purine + pentose-1-phosphate. It is suggested that pnd mutations affect the structural gene of some phosphorolytic enzyme and modify its substrate specificity. Evidence is presented that the structural gene of a new nucleoside phosphorylase is not sensitive to catabolite repression.