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1.
Zh Obshch Biol ; 63(6): 473-93, 2002.
Article in Russian | MEDLINE | ID: mdl-12510587

ABSTRACT

The basic concepts, notions and methods of geometric morphometrics (GM) are considered. This approach implies multivariate analysis of landmark coordinates located following certain rules on the surface of a morphological object. The aim of GM is to reveal differences between morphological objects by their shapes as such, the "size factor" being excluded. The GM is based on the concept of Kendall's space (KS) defined as a hypersphere with points distributed on its surface. These points are the shapes defined as aligned landmark configurations. KS is a non-Euclidian space, its metrics called Procrustes is defined by landmark configuration of a reference shape relative to which other shapes are aligned and compared. The differences among shapes are measured as Procrustes distances between respective points. For the linear methods of multivariate statistics to be applied to comparison of shapes, the respective points are projected onto the tangent plane (tangent space), the tangent point being defined by the reference. There are two principal methods of shape comparisons in GM: the Procrustes superimposition (a version of the least squares analysis) and thin-plate spline analysis. In the first case, Procrustes residuals are the outcome shape variables which remain after isometric alignment of the shapes being compared. Their summation over all landmarks yields Procrustes distances among these shapes. The Procrustes distances can be used in multivariate analyses just as the Euclidian distances. In the second case, the shapes are fitted to the references by stretching/compressing and shearing until complete identity of their landmark configurations. Eigenvectors of resulting bending energy matrix are defined as new shape variables, principal warps which yield another shape space with the origin defined by the reference. Projections of the shapes being compared onto principal warps yield partial warps, and their covariance matrix decomposition into eigenvectors yields relative warps which are similar to principal components (in particular, they are mutually orthogonal). Both partial and relative warps can be used in many multivariate statistic analyses as quantitative shape variables. Results of thin-plate spline analysis can be represented graphically by transformation grid which displays type, amount and localization of the shape differences. Basis rules of sample composition and landmark positioning to be used in GM are considered. At present, rigid (with minimal degrees of freedom) 2D morphological objects are most suitable for GM applications. It is important to recognize three type of real landmarks, and additionally semi-landmarks and "virtual" landmarks. Some procedures of thin-plate spline analysis are considered exemplified by some study cases, as well as applications of some standard multivariate methods to GM results. They make it possible to evaluate correlation between different shapes, as well as between a shape and some non-shape variables (linear measurements etc); to evaluate the differences among organisms by shape of a morphological structure; to identify landmarks which most accounted for both correlation and differences between the shapes. An annotated list of most popular softwares for GM is provided.


Subject(s)
Body Patterning , Models, Anatomic , Animals , Biometry/methods , Brachyura/anatomy & histology , Computer Graphics , Data Display , Mathematics , Rodentia/anatomy & histology , Software
2.
Article in Russian | MEDLINE | ID: mdl-2115382

ABSTRACT

The effect of extracellular calcium binding and temperature of isolation and storage of thymus lymphocytes on their viability was studied. The last was evaluated by the fluorescence intensity of fluoresceindiacetate stained cells and by the intracellular ATP content. The rise of temperature of isolation and storage of lymphocytes from 1 degree to 22 degrees C significantly lowered the intracellular ATP concentration in cells storing in dense suspension [(3-4) x 10(9) lymphocytes/ml]. However, the ATP content in lymphocytes increased as a result of short-term incubation by diluted suspension (3 x 10(7) lymphocytes/ml) at 22 degrees C. The fluorescence of fluorescein introduced into lymphocytes decrease in the presence of 1-5 mM EGTA (EDTA).


Subject(s)
Calcium/pharmacology , Lymphocytes/drug effects , Temperature , Animals , Cell Separation , Cell Survival/drug effects , Edetic Acid/pharmacology , Egtazic Acid/pharmacology , Fluoresceins , Lymphocytes/physiology , Microscopy, Fluorescence , Rats , Thymus Gland/cytology
4.
Article in Russian | MEDLINE | ID: mdl-6624347

ABSTRACT

The problem of efficacy prediction for psychopharmacotherapy of depressions is of considerable interest and urgency in view of frequently occurring resistance to antidepressants. The purpose of the present study was to study the feasibility of predicting the effectiveness of depression therapy in manic-depressive psychosis (MDP), based on the cross-sectional analysis of the patient's history (the clinical picture of the patient's condition prior to therapy) with the help of multivariate statistics. Eighty-two patients suffering from MDP with a variety of depressive states were examined. In addition to traditional descriptions, the clinical findings were documented by employing a system of standard evaluation scales. The data obtained were processed using the technique of multiple stepwise discriminant analysis. The latter resulted in the derivation of a mathematical prognostic formula allowing the prediction of tricyclic antidepressants efficacy.


Subject(s)
Antidepressive Agents, Tricyclic/therapeutic use , Bipolar Disorder/drug therapy , Adult , Aged , Anxiety/drug therapy , Bipolar Disorder/diagnosis , Diagnosis, Differential , Drug Resistance , Electroconvulsive Therapy , Female , Humans , Hypochondriasis/drug therapy , Male , Middle Aged , Monoamine Oxidase Inhibitors/therapeutic use , Syndrome
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