Multimodal Optical Diagnostics of Glycated Biological Tissues.

Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia accompanied by the disruption of carbohydrate, lipid, and proteins metabolism and development of long-term microvascular, macrovascular, and neuropathic changes. This review presents the results of spectroscopic studies on the glycation of tissues and cell proteins in organisms with naturally developing and model diabetes and in vitro glycated samples in a wide range of electromagnetic waves, from visible light to terahertz radiation. Experiments on the refractometric measurements of glycated and oxygenated hemoglobin in broad wavelength and temperature ranges using digital holographic microscopy and diffraction tomography are discussed, as well as possible application of these methods in the diabetes diagnostics. It is shown that the development and implementation of multimodal approaches based on a combination of phase diagnostics with other methods is another promising direction in the diabetes diagnostics. The possibilities of using optical clearing agents for monitoring the diffusion of substances in the glycated tissues and blood flow dynamics in the pancreas of animals with induced diabetes have also been analyzed.

Time-resolved inline digital holography for the study of noncollinear degenerate phase modulation.

Recent works demonstrated that digital time-resolved holography is the prospective approach to study nonlinear light-matter interaction processes. In this Letter, we present a straightforward inline holographic approach for studying degenerate phase modulation induced by an inclined collimated pump beam in the isotropic sample. The method is based on a minimization of the difference between experimentally acquired data and simulated inline holograms obtained from a numerical model of pump-probe interaction in optical nonlinear media. A sophisticated experimental data processing algorithm is implemented to provide high sensitivity and a signal-to-noise ratio eligible for soft interaction with a collimated pump beam. The integral phase shift determined by our method can be used to estimate the nonlinear refractive index and the relaxation time for material with a low damage threshold. We validated our approach for the case of soda-lime and BK7 glasses.

Digital holographic microscopy in label-free analysis of cultured cells' response to photodynamic treatment.

A methodology providing noninvasive monitoring and evaluation of the effect of photodynamic treatment on live cells in vitro is presented. Variations in morphological characteristics of cells in the course and after treatment are recorded by means of digital holographic microscopy. High-precision measurements of phase shift gained by probe radiation in HeLa and human endometrial mesenchymal stem cell cultures demonstrate for the first time changes of their volume occurred in response to treatment.

Accuracy of image-plane holographic tomography with filtered backprojection: random and systematic errors.

This paper explores the concept of image-plane holographic tomography applied to the measurements of laser-induced thermal gradients in an aqueous solution of a photosensitizer with respect to the reconstruction accuracy of three-dimensional variations of the refractive index. It uses the least-squares estimation algorithm to reconstruct refractive index variations in each holographic projection. Along with the bitelecentric optical system, transferring focused projection to the sensor plane, it facilitates the elimination of diffraction artifacts and noise suppression. This work estimates the influence of typical random and systematic errors in experiments and concludes that random errors such as accidental measurement errors or noise presence can be significantly suppressed by increasing the number of recorded digital holograms. On the contrary, even comparatively small systematic errors such as a displacement of the rotation axis projection in the course of a reconstruction procedure can significantly distort the results.

Wavefront reconstruction in digital off-axis holography via sparse coding of amplitude and absolute phase.

This work presents the new method for wavefront reconstruction from a digital hologram recorded in off-axis configuration. The main feature of the proposed algorithm is a good ability for noise filtration due to the original formulation of the problem taking into account the presence of noise in the recorded intensity distribution and the sparse phase and amplitude reconstruction approach with the data-adaptive block-matching 3D technique. Basically, the sparsity assumes that low dimensional models can be used for phase and amplitude approximations. This low dimensionality enables strong suppression of noisy components and accurate revealing of the main features of the signals of interest. The principal point is that dictionaries of these sparse models are not known in advance and reconstructed from given noisy observations in a multiobjective optimization procedure. We show experimental results demonstrating the effectiveness of our approach.

Digital off-axis holographic interferometry with simulated wavefront.

The paper presents a novel algorithm based on digital holographic interferometry and being promising for evaluation of phase variations from highly noisy or modulated by speckle-structures digital holograms. The suggested algorithm simulates an interferogram in finite width fringes, by analogy with classical double exposure holographic interferometry. Thus obtained interferogram is then processed as a digital hologram. The advantages of the suggested approach are demonstrated in numerical experiments on calculations of differences in phase distributions of wave fronts modulated by speckle structure, as well as in a physical experiment on the analysis of laser-induced heating dynamics of an aqueous solution of a photosensitizer. It is shown that owing to the inherent capability of the approach to perform adjustable smoothing of compared wave fronts, the resulting difference undergoes noise filtering. This capability of adjustable smoothing may be used to minimize losses in spatial resolution. Since the method allows to vary an observation angle of compared wave fields, an opportunity to compensate misalignment of optical axes of these wave fronts arises. This feature can be required, for example, when using two different setups in comparative digital holography or for compensation of recording system displacements during a set of exposures in studies of dynamic processes.

[Direct angioplasty of the left main coronary artery with a pericardium flap].

Surgical treatment of stenosis of the left main coronary artery (LMCA) is a special problem, a number of questions of surgical strategy for this lesion still remain unsolved. The question of direct plasty dilatation of LMCA has not lost its actuality. Operations were made on 6 patients in whom direct plasty dilatation of LMCA with a flap from autopericardium was performed for local, not lengthy constriction which was located in the initial and middle part of LMCA. The operations were made under conditions of extracorporeal circulation, moderate general hypothermia (about 32 degrees C), pharmacohypothermic cardioplagia with external cooling of the heart. In all cases there was good restoration of cardiac activity and the absence of myocardium ischemia at the postoperative period. The restoration of the anatomical lumen of LMCA by this method facilitated sufficient blood flow along LMCA. Five years later all the patients are alive, one patient has external angina of the 11 functional class.

[Cytogenetic effects of cholinotropic preparations mixture on Chironomus plumosus (Diptera) larvae in vivo].

Morphometric analysis of changes in nucleolar organizer (NO), Balbiani rings (BR)--BR(B), BR(1G), BR(2G) and chromosome I arm B puff activities, and in chromosome compactness of Chironomus plumosus (Diptera) polytene chromosomes was carried out in acute period under separate and combined influence of atropine and pilocarpine. Supression effect of cholinotropic preparations mixture was revealed. Suppression of NO activity with atropine concentration increase in the mixture served as criterion of toxicity.

[Genetic structure of the Udmurt population].

Integrated study of the genetic structure of the Udmurt population with respect to different genetic systems has been performed. Data on the genes of genetic diseases, abiotic parameters analyzed by population statistic methods, and DNA polymorphism are summarized. The populations of six raions (districts) of Udmurt Republic (the Mozhga, Malaya Purga, Sharkan, Debesy, Igra, and Glazov raions) have been studied. The total population studied was 267,655 people (an urban population of 150,119 people and a rural population of 117,536 people), including 155,346 Udmurts. The population structure has been studied in six districts on the basis of the vital statistics, Crow's indices, Malecot's isolation by distance parameters, ethnically assortative marriage parameters, endogamy indices, inbreeding-endogamy (ie) indices, and frequencies of the genotype and allele frequencies of four DNA markers (17 alleles). The prevalences of hereditary diseases have been calculated for different population groups: urban and rural populations, Udmurts and other ethnic groups. These groups, especially the urban and rural populations, substantially differed from one another in the prevalences of autosomal dominant (AR) and autosomal recessive (AR) diseases. The correlation between the prevalence of AD and AR diseases and the ie index is positive and significant. The spectrum of hereditary diseases detected in six districts of Udmurtia comprises 149 diseases (80, 57, and 12 AD, AR, and X-linked diseases, respectively). Accumulation of individual diseases in districts of Udmurtia and accumulation of diseases in Udmurtia as compared to regions studied earlier has been found. Cluster analysis of the frequencies of genes of AD and AR diseases and DNA markers has determined the gene geographic position of Udmurts.

[Effectiveness of using autologous mono-nuclears of the bone marrow in treatment of patients with ischemic heart disease].

The authors have analyzed their experiences with treatment of 50 patients with ischemic heart disease using transplantation of autologous mono-nuclears of the bone marrow. It was shown that this operation resulted in an improvement of indices of the heart functions and myocardium metabolism. Transplantation of stem cells as mononuclear fraction of the bone marrow is indicated in treatment of different groups of patients: in recurrent diseases after previous operations on the coronary arteries; in patients with distal lesions of the coronary bed; transplantation of autologous stem cells of the bone marrow is expedient simultaneously with coronary artery bypass grafting or coronary angioplasty (stenting).

[Treatment of infected pseudarthroses of the tibia complicated by defects of soft tissues]. / Lechenie infitsirovannykh lozhnykh sustavov bol'shebertsovoi kosti, oslozhnennykh defektom miagkikh tkanei.

On the basis of experience in the treatment of 51 patients with infected false joints of the tibia the authors conclude that local circulatory disorders play the decisive role in the genesis of nonunion of the fracture. The recommended methods for removal of the soft tissue defect by various types of pedicled skin grafts in combination with fixation of the fragments and plastic repair, in some cases, of the false joint zone with demineralized bone allografts made it possible to remove the inflammatory process radically and achieve consolidation in 94% of patients who were operated on.

Settlement in large cities of the USSR: an analysis of effectiveness (a review article).

"The issue of the effectiveness of large cities as forms of settlement remains a lively topic of debate in the USSR. Categorizing the issue into three aspects--economic, ecological and social--this paper reviews the arguments pro and con. Although the author makes a conscientious effort to reflect all points of view, a tone favoring the development of big cities appears evident in the discussion."

[Analysis of the choline-sensitizing action of haloperidol on mollusk neurons]. / Analiz kholinsensibiliziruiushchego deistviia galoperidola na neirony molliuska.

It was shown on identified neurons of freshwater mollusk Lymnaea stagnalis that depending on the concentration haloperidol enhanced chlorine-induced depolarizing effect of carbacholine. A shift of the concentration-effect curve for carbacholine against the background of the neuroleptic action to the left on the axis of abscissae with the preservation of its maximum indicates the allosteric interaction of haloperidol with that part of the choline receptor structure which is territorially isolated from its recognizing centre.