[The study of lipofuscin levels in the 5xFAD mouse model of Alzheimer's disease.]

In this study, we evaluated the change in the level of lipofuscin, an autofluorescent aging pigment, in brain and peripheral tissues in a transgenic mouse model of Alzheimer's disease (AD) - 5xFAD. A comparative analysis of the content of lipofuscin in homogenates of the liver, kidneys, heart, and various parts of the brain of 5xFAD mice, as well as control mice from the same litters of different ages, was carried out. The data obtained correlate well with the concept of lipofuscin as an aging pigment - its amount increases with age in both control and 5xFAD mice. We noted accumulation of lipofuscin progressive with age in 5xFAD mice, which is detected both in different parts of the brain and in peripheral organs. At the same time, the level of lipofuscin was increased even in newborn day-old mice 5xFAD. Thus, an increase in the level of lipofuscin in 5xFAD mice is one of the earliest disorders that manifests itself not only in the brain, but also in other organs.

Highly efficient stimulated Raman scattering of sub-picosecond laser pulses in BaWO4 for 10.6 µm difference frequency generation.

Transient stimulated Raman scattering (SRS) of 0.3 ps 515 nm laser pulses in ${\rm BaWO_4}$BaWO4 crystal was experimentally demonstrated with efficiency up to ${\sim}{20}\% $∼20% for the Stokes component with a wavenumber of ${\sim}{925}\;{{\rm cm}^{ - 1}}$∼925cm-1 in a simple single-pass geometry. This anomalous high efficiency was obtained due to the laser pulse self-phase modulation resulting in spectral broadening and seeding the SRS. The applicability of seed pulse production for a high-pressure sub-picosecond ${{\rm CO}_2}$CO2 laser amplifier via difference frequency generation in ${{\rm LiGaS}_2}$LiGaS2 crystal was numerically verified.

[Tyndall's hypochromism in suspensions].

Since the passage of light through each individual particle in a suspension includes the competition of processes of absorption and scattering, it leads to hypochromism--a decrease in the extinction coefficient. Such "scattering" hypochromism increases with the particle size and its refractive index. Since the Tyndall's light scattering in suspensions, where the size of each particle is substantially larger with respect to wavelengths of light, is not strongly dependent on the wavelength, the absorption spectrum (and excitation spectrum) attenuated almost uniformly at different wavelengths. A simple method to find true extinction coefficients from the absorption (or excitation) spectra of diluted suspensions (not having multiple light scattering) is suggested. The experimental data on spectra of hemoglobin in erythrocytes, actinomycin in DNA and flavins in mitochondria are given.

[Fluorescence study of energetics in nucleotide-actinomycin complexes].

Variety of different compounds use for delivery of antibiotics to the tumor cells. In this work, using a highly sensitive fluorescence analysis, we have studied complexes of fluorescent analog of the natural heterocyclic antibiotic actinomycin D (7-aminoactinomycin D) with potential carriers: purine bases and fragmented DNA. The antibiotic is not only adsorbed on the surface ofpurine clusters, but also is embedded in them. The antibiotic is especially well integrated into the unwound DNA regions. Embedding is accompanied by a long-wavelength shift in the excitation spectrum. The magnitude of the shift was used for calculation of the interaction energy. In the case of AMD with guanine, caffeine and adenine, the value of energy was about of 7 kcal/mol and in the case of fragmented DNA it was only a bit higher: 7.7 kcal/mol. It can be assumed that guanine, adenine, caffeine, and the fragmented DNA could apply as carriers of antibiotic.

A Mouse Model of Sporadic Alzheimer's Disease with Elements of Major Depression.

After olfactory bulbectomy, animals are often used as a model of major depression or sporadic Alzheimer's disease and, hence, the status of this model is still disputable. To elucidate the nature of alterations in the expression of the genome after the operation, we analyzed transcriptomes of the cortex, hippocampus, and cerebellum of the olfactory bulbectomized (OBX) mice. Analysis of the functional significance of genes in the brain of OBX mice indicates that the balance of the GABA/glutamatergic systems is disturbed with hyperactivation of the latter in the hippocampus, leading to the development of excitotoxicity and induction of apoptosis in the background of severe mitochondrial dysfunction and astrogliosis. On top of this, the synthesis of neurotrophic factors decreases leading to the disruption of the cytoskeleton of neurons, an increase in the level of intracellular calcium, and the activation of tau protein hyperphosphorylation. Moreover, the acetylcholinergic system is deficient in the background of the hyperactivation of acetylcholinesterase. Importantly, the activity of the dopaminergic, endorphin, and opiate systems in OBX mice decreases, leading to hormonal dysfunction. On the other hand, genes responsible for the regulation of circadian rhythms, cell migration, and innate immunity are activated in OBX animals. All this takes place in the background of a drastic downregulation of ribosomal protein genes in the brain. The obtained results indicate that OBX mice represent a model of Alzheimer's disease with elements of major depression.

Dynamics of the Stokes pulse in a Brillouin amplifier.

We show that the output Stoke pulse from a continuously (CW) pumped stimulated Brillouin scattering (SBS) amplifier is the sum of the transmitted input Stokes pulse, which propagates undistorted through the medium without amplification and additional delay, and of a Stokes shifted pump signal reflected by the electrostrictively induced acoustic wave, which contributes to the Stokes output signal with a delay determined by the time required for build up of the acoustic wave.

"Slow Light" in Stimulated Brillouin Scattering: on the influence of the spectral width of pump radiation on the group index: reply.

We show that the claims in the Comment arise from widespread misconceptions of the principles of both SBS and "slow light" phenomena.

"Slow Light" in stimulated Brillouin scattering: on the influence of the spectral width of pump radiation on the group index: Reply.

We show that the claims in the Comment are misleading and in instances contradictory.

"Slow Light" in stimulated Brillouin scattering: on the influence of the spectral width of pump radiation on the group index.

An analytical solution of the basic coupled stimulated Brillouin scattering (SBS) equations is obtained in the Fourier domain, which describes the spectral evolution of the medium's response, and that of a Stokes pulse injected into this medium, when SBS is excited by non-monochromatic CW pump radiation. It shows that spectral broadening of pump radiation by any reasonable amount results in only minute increase of the spectral width of the resonant material's excitation in SBS, and cannot be effective in modifying the natural group index of the medium for the Stokes pulse.

Effect of acoustic wave inertia and its implication to slow light via stimulated Brillouin scattering in an extended medium.

An analytical solution of the basic coupled stimulated Brillouin scattering (SBS) equations is obtained which describes the evolution of a Stokes pulse injected into an extended Brillouin medium excited by CW pump radiation. We show that regardless of the pulse length of the input Stokes pulse the delay of the output Stokes pulse results entirely from the inertia of the acoustic wave excitation via the electrostrictive interaction of the Stokes pulse with CW pump radiation. This delay is the SBS build up time and not the SBS induced group delay normally attributed to slow light.

Abnormally low threshold gain of stimulated Brillouin scattering in long optical fiber with feedback.

We show that in the generation of stimulated Brillouin scattering (SBS) in long (> 1 km) fiber, the threshold for observing coherent Stokes emission occurs at notably lower gain than the classical lasing threshold gain for SBS. The effect is due coherent regenerative amplification of strong spontaneous Brillouin scattering, which occurs in the presence of feedback. The magnitude of the effect scales with the length of interaction.

Threshold for stimulated Brillouin scattering in optical fiber.

We show that in optical fiber the threshold exponential gain, Gth, for stimulated Brillouin scattering initiated by spontaneous Brillouin scattering is functionally and strongly dependent on the material, length and numerical aperture of the fiber and the pump wavelength. For silica fiber we show that the value of G(th) at lambda congruent with 1 microm ranges from as low as approximately 5 in long fiber ( > or =few kms) to ~10-12 in fibers of approximately 100 m length and approximately 20-23 for very short fibers (<10 cm).

Nucleotide carriers for anti-tumour actinomycin antibiotics.

We have investigated a number of complexes of 7-aminoactinomycin D (7AAMD), with its potential carriers: caffeine, folic acid (FA), purine bases-guanine and adenine, pyrimidine base-thymine and with fragmented DNA to determine more stable and suitable complex. The process of binding of the fluorescent antibiotic with clusters of caffeine, guanine, adenine, thymine and with fragmented DNA was accompanied by a considerable long-wavelength shift in excitation spectrum. The energy of interaction between phenoxazine hetero-cycle of 7AAMD and chromophores of the carriers studied has been found. In the case of 7AAMD with guanine, adenine, thymine and caffeine, the energy is about of 7 kcal/mol, which is a little lower than in the case with DNA (7.7 kcal/mol). On the basis of emission spectra, in all examined compounds, with the exception DNA, the 7AAMD molecule emits photons from water phase, not from a cluster, since photo-excitation leads to desorption of the antibiotic from a cluster surface. We observed also the mutual fluorescence quenching of 7AAMD and FA in their complex. It may well be that this complex forms due to interaction of peptide-lactone rings of 7AAMD with system of FA. In the case of DNA, the complex with 7AAMD has very high stability that is determined not only by interaction between phenoxazine of 7AAMD and the DNA bases, but it is largely owing to the interaction between two peptide-lactone rings of 7AAMD and the DNA deoxyribose-phosphate chains.

[Use of intra-arterial chemotherapy in the treatment of malignant tumors in children]. / Primenenie vnutriarterial'noi khimioterapii v lechenii zlokachestvennykh opukholei u detei.

Transcatheter arterial chemotherapy has been perfected in the treatment of 66 patients with various severe malignant tumors. A total of 75 arterial cytostatic injections were made, out of them 57 were given in primary tumors and 18 in tumor metastases. The children's age ranged from 1 to 14 years. High arterial therapeutic doses in combination with extracorporeal blood purification by hemosorption in the treatment of hepatic metastases yielded 100% efficiency. Prolonged arterial chemotherapy for pulmonary metastases provided an excellent therapeutic effect. Thus, 75 arterial injections of cytostatics gave rise to 32% of complete remissions, 48% of partial remissions. There was no benefit in 20% of cases. Adverse reactions were absent.

[Disseminated intravascular coagulation syndrome in myocardial infarct]. / O sindrome disseminirovannogo vnutrisosudistogo svertyvaniia pri infarkte miokarda.

To establish the incidence of the disseminated intravascular coagulation (DIC) syndrome, 76 patients who had died from acute myocardial infarction were clinically and anatomically analysed. The studies indicated that microcirculatory thrombosis in myocardial infarction occurred in the first to early second weeks of its development and localized in minor veins of one organ and only in 21.4% of cases it involved three organs or more. The DIC-syndrome was morphologically evidenced only in 19.1% of the patients having a history of cardiogenic shock. Microcirculatory thrombosis more frequently occurred in females. Old age, persistent hypertension, diabetes mellitus were found to predispose to its development.

[Experience in delivering specialized surgical care in a large hospital]. / Opyt okazaniia spetsializirovannoi khirurgicheskoi pomoshchi v krupnom gospitale.

Medical troops supply in local armed conflicts demonstrated advantages of fast evacuation of wounded personnel by aviation from the seat of combat actions to the stage of specialized surgical care. Wounded in head, breast, abdomen (particularly in case of multiple and combined character of wounds) are evacuated for treatment to central military hospitals equipped with modern diagnostic and medical equipment, completed with qualified specialists and having the opportunity of prolonged treatment. Surgical care in the zone of combat actions is confined to hemostasis, intensive therapy -to supporting of main vital functions. The article contains the data about terminations of wounded personnel treatment in central military-fleet clinical hospital.

Resonant enhancement of the transversal Kerr effect in the InMnAs layers.

Spectral dependences of the transversal Kerr effect (TKE) as well as of the real and imaginary parts of the permittivity of InMnAs layers were studied. Pulsed laser ablation of Mn and InAs targets was used to form the layers on GaAs(100) substrates. Spectra of the optical constants and TKE depended substantially on layer fabrication conditions and testified to the presence of MnAs inclusions in the samples. The cross-sectional transmission electron microscopy revealed the presence of inclusions of size 10-40 nm in the layers. At room temperature a strong resonant band was observed in the TKE spectra of the InMnAs layers in the energy range of 0.5-2.2 eV. In this band the TKE was comparable in magnitude but opposite in sign to that in the strong ferromagnetic MnAs. The resonant character of the TKE spectra was explained by excitation of surface plasmons in the MnAs nanoclusters embedded in the InMnAs semiconductor host. Modelling the TKE spectra for (InAs)(1 - X):(MnAs)(X) nanocomposites in the effective-medium approximation (Maxwell-Garnett approximation) confirmed the assumption on the plasmon mechanism of the resonant enhancement of the transversal Kerr effect in the InMnAs layers.