Multimodal embryonic imaging using optical coherence tomography, selective plane illumination microscopy, and optical projection tomography.

The murine model is commonly utilized for studying developmental diseases. Different optical techniques have been developed to image mouse embryos, but each has its own set of limitations and restrictions. In this study, we compare the performance of the well-established technique of optical coherence tomography (OCT) to the relatively new methods of selective plane illumination microscopy (SPIM) and optical projection tomography (OPT) to assess murine embryonic development. OCT can provide label free high resolution images of the mouse embryo, but suffers from light attenuation that limits visualization of deeper structures. SPIM is able to image shallow regions with great detail utilizing fluorescent contrast. OPT can provide superior imaging depth, and can also use fluorescence labels but, it requires samples to be fixed and cleared before imaging. OCT requires no modification of the embryo, and thus, can be used in vivo and in utero. In this study, we compare the efficacy of OCT, SPIM, and OPT for imaging murine embryonic development. The data demonstrate the superior capability of SPIM and OPT for imaging fine structures with high resolution while only OCT can provide structural and functional imaging of live embryos with micrometer scale resolution.

[A role of the adhesive properties of leucocytes and blood serum in the pathogenesis of multiple sclerosis].

Adhesive properties of leucocytes were studied using an original technique based on the leukocyte adherence inhibition reaction and measuring the values of spontaneous adhesion index (SAI) and adhesion-strengthening effect (ASE) under the influence of autoserum. One hundred patients with multiple sclerosis (MS) and 53 controls were included in the study. Immunophenotyping of lymphocytes (LP) with monoclonal antibodies--markers CD3, CD4, CD8, CD16, CD20, CD25, HLA-DR and CD95--and determination of IgG, IgA, IgM and content of immune complexes were carried out in parallel. The increase of adhesion parameters (ASE and SAI) was found in MS. It was most significant in patients with primary progressive course and in disease exacerbation. The greatest changes of phenotypic LP content were associated with debut and exacerbation-remission periods. Significant positive correlations between higher SAI values and phenotypes CD20, CD95, HLA-DR and amount of natural killer cells were revealed in patients with MS in contrast to the negative correlations of SAI with CD3 and CD4 in the control group. A role of membrane and soluble forms of adhesion molecules in the initiation and progression of immunopathological process in MS is discussed.

[Clinical significance of adhesive properties of leukocytes and blood serum in patients with multiple sclerosis].

Adhesive blood properties have been studied in 100 MS patients with the help of the new method developed on the basis of the leucocyte adherence inhibition (LAI) test, which was based on the calculation of the ratio of adhesive cells to non-adhesive ones. The value obtained was called the Index of Spontaneous Adhesion (ISA), while the respective indicator reflecting the effect of adhesion strengthening under the influence of autoserum, being expressed by 30% and more, was named the Effect of the Adhesion Strengthening (ES-a). Blood samples of 54 donors and 31 patients with other neurological diseases were used as controls. Statistically significant increase of ISA values of MS patients was detected as compared to the group of donors. The highest indices of ISA and ES-a were found in the primarily progressive course and at the stage of MS exacerbation in the remitting course. Correlation between levels of adhesion and clinical features as well as parameters of clinical and humoral immunity are described. A role of membrane and soluble forms of adhesion molecules in initiation and progression of the immunologic process in MS is discussed.

Noninvasive monitoring of glucose concentration with optical coherence tomography.

We have proposed a tested in tissue phantoms and in vivo a novel sensor based on optical coherence tomography (OCT) for noninvasive and continuous monitoring of blood glucose concentration. OCT images were obtained from pig and rabbit skin before and after glucose administration. Slopes of OCT signals decreased substantially (~40% in tissues in vivo) and linearly with the increase of blood glucose concentration from 4 to 30 mM, typical for normal and diabetic subjects. Phantom studies demonstrated 1% accuracy of scattering-coefficient measurement. Our theoretical and experimental studies suggest that glucose concentration can potentially be measured noninvasively with high sensitivity and accuracy with OCT systems.

Effects of the 120 days of head-down bed rest on cytokine secretion and its in vitro modulation by glucocorticoids.

Antiorthostatic hypokinesia or head-down bed rest (HDBR), is a ground-based model system used to simulate some of the physioloical responses observed during space flight. Several studies involving humans and animals have demonstrated the effects of HDBR on different physioloical systems. HDBR produced a large thoracic fluid shift similar to that reported for space flight. Exposure to the combination of -6 degrees HDBR, emotional stress, and hypergravity led to an elevation of plasma histamine and serotinin and a dramatic decrease in the concentration of prostaglandins E, F2-alpha, and erthropoietin. These responses indicated the HDBR produces significant alterations in the neuroendocrine regulatory pathways. The proliferative response of immune cells in response to activators was significantly enhanced in antiorthostatically suspended mice; plasma corticosterone also was higher but splenic natural killer cell cytotoxicity remained unchanged after suspension. Bone-resporbing activity of supernatatants increased in mitogen-stimulated PBMC cultures of subjects exposed to -5 degrees HDBR for 370 days of HDBR. Proliferative activity of PBMCs had declined at the end of a 320-day HDBR and during the initial days of recovery, but the numbers of active rosette-forming T cells increased. These and other results suggest that most stress-induced immune changes are neuroendocrine modulated, and that corticosteroids play a significant role in this modulation. It is expected that HDBR-induced immune changes could result from similar mechanisms. In this study, we investigated the effect of 120 days of HDBR on Type-1 vs. Type-2 cytokine equilibrium in mitogen-activated PBMC culture, and how these reactions may correlate with changes in the neuroendocrine status.