Laser specklometer for determining the biomechanical parameters of skeletal muscles and the microhaemodynamics of human skin

Author(s):  
Leonid V. Tanin ◽  
Sergei C. Dick ◽  
Serguei A. Alexandrov ◽  
Mikhail M. Loiko ◽  
A. A. Kumeisha ◽  
...  
2021 ◽  
Vol 13 (3) ◽  
pp. 495-503
Author(s):  
Anna-Liisa Tamm ◽  
Ivi Vaher ◽  
Reet Linkberg ◽  
Teet Tilk ◽  
Jana Kritt ◽  
...  

Background: There are non-invasive methods of correcting genu valgum (GV), but to date, there is no method to evaluate mechanotherapeutic intervention that does not restrict child’s natural movements while the process is on-going so that timely decisions could be made on effectiveness of intervention. The aim of study was to develop and assess the comfortability of garments with elastic straps and pressure applicator (GESPA) and the reliability and user-friendliness of “GVcorrect” app, which aims to catch the elastic straps’ pressure level (mN). Methods: 6 children (5–7 y) with intermalleolar distance ≥5 cm wore GESPA daily for 3 months. Anthropometrical and goniometrical measurements were done according to standard technique; tone and biomechanical parameters of skeletal muscles determined with MyotonPRO; feedback about GESPA and “GVcorrect” collected via questionnaire. Results: Based on feedback from children and parents, new, more comfortable and user-friendly GESPA were designed; several updates were made to “GVcorrect” app; new goals were set for the next phase of the study. Conclusions: GESPA and the “GVcorrect” app serve their purpose, but there are still a number of important limitations that need to be removed before the product can be marketed. The study continues with product development until a medical device certificate is obtained.


Author(s):  
KONSTANTIN K. BONDARENKO ◽  
Anastasiya D. Lebed

Modern sports make high requirements for the implementation of technical elements of the movement. Evaluation of shock actions when serving in big tennis allows you to model the technical training of athletes. The purpose of the article is to determine the kinematic parameters of the movement of body links when performing a pitch in tennis. To perform a motion analysis, we used a knot position method to determine the structural elements of the motion. Depending on the pedagogical tasks, we revealed the main characteristics of the movement using nodes. We determined angular deviations from anatomical positions in joints, between body links performing efficiency of performed action. We revealed the most rational ranges of angular positions between segments of the body. Analysis of biomechanical parameters of movement allows to determine rational trajectories of movement of body links, which makes it possible to select the most effective serving and special exercises aimed at formation of the most effective motor actions and reduction of tension during movement in the player's joints and skeletal muscles. These biomechanical data can then be useful to improve the organization and planning of the training process of tennis players. Knowledge of the range of angular movements and the nature of the change in relative body links helps to reduce joint injuries when serving in tennis.


Author(s):  
Douglas R. Keene ◽  
Robert W. Glanville ◽  
Eva Engvall

A mouse monoclonal antibody (5C6) prepared against human type VI collagen (1) has been used in this study to immunolocalize type VI collagen in human skin. The enbloc method used involves exposing whole tissue pieces to primary antibody and 5 nm gold conjugated secondary antibody before fixation, and has been described in detail elsewhere (2).Biopsies were taken from individuals ranging in age from neonate to 65 years old. By immuno-electron microscopy, type VI collagen is found to be distributed as a fine branching network closely associated with (but not attached to) banded collagen fibrils containing types I and III collagen (Fig. 1). It appears to enwrap fibers, to weave between individual fibrils within a fiber, and to span the distance separating fibers, creating a “web-like network” which entraps fibers within deep papillary and reticular dermal layers (Fig. 2). Relative to that in the dermal matrix, the concentration of type VI collagen is higher around endothelial basement membranes limiting the outer boundaries of nerves, capillaries, and fat cells (Fig. 3).


Author(s):  
D. A. Fischman ◽  
J. E. Dennis ◽  
T. Obinata ◽  
H. Takano-Ohmuro

C-protein is a 150 kDa protein found within the A bands of all vertebrate cross-striated muscles. By immunoelectron microscopy, it has been demonstrated that C-protein is distributed along a series of 7-9 transverse stripes in the medial, cross-bridge bearing zone of each A band. This zone is now termed the C-zone of the sarcomere. Interest in this protein has been sparked by its striking distribution in the sarcomere: the transverse repeat between C-protein stripes is 43 nm, almost exactly 3 times the 14.3 nm axial repeat of myosin cross-bridges along the thick filaments. The precise packing of C-protein in the thick filament is still unknown. It is the only sarcomeric protein which binds to both myosin and actin, and the actin-binding is Ca-sensitive. In cardiac and slow, but not fast, skeletal muscles C-protein is phosphorylated. Amino acid composition suggests a protein of little or no αhelical content. Variant forms (isoforms) of C-protein have been identified in cardiac, slow and embryonic muscles.


Author(s):  
A. P. Lupulescu ◽  
H. Pinkus ◽  
D. J. Birmingham

Our laboratory is engaged in the study of the effect of different chemical agents on human skin, using electron microscopy. Previous investigations revealed that topical use of a strong alkali (NaOH 1N) or acid (HCl 1N), induces ultrastructural changes in the upper layers of human epidermis. In the current experiments, acetone and kerosene, which are primarily lipid solvents, were topically used on the volar surface of the forearm of Caucasian and Negro volunteers. Skin specimens were bioptically removed after 90 min. exposure and 72. hours later, fixed in 3% buffered glutaraldehyde, postfixed in 1% phosphate osmium tetroxide, then flat embedded in Epon.


Author(s):  
R. R. Warner

Keratinocytes undergo maturation during their transit through the viable layers of skin, and then abruptly transform into flattened, anuclear corneocytes that constitute the cellular component of the skin barrier, the stratum corneum (SC). The SC is generally considered to be homogeneous in its structure and barrier properties, and is often shown schematically as a featureless brick wall, the “bricks” being the corneocytes, the “mortar” being intercellular lipid. Previously we showed the outer SC was not homogeneous in its composition, but contained steep gradients of the physiological inorganic elements Na, K and Cl, likely originating from sweat salts. Here we show the innermost corneocytes in human skin are also heterogeneous in composition, undergoing systematic changes in intracellular element concentration during transit into the interior of the SC.Human skin biopsies were taken from the lower leg of individuals with both “good” and “dry” skin and plunge-frozen in a stirred, cooled isopentane/propane mixture.


Author(s):  
L.X. Oakford ◽  
S.D. Dimitrijevich ◽  
R. Gracy

In intact skin the epidermal layer is a dynamic tissue component which is maintained by a basal layer of mitotically active cells. The protective upper epidermis, the stratum corneum, is generated by differentiation of the suprabasal keratinocytes which eventually desquamate as anuclear comeocytes. A similar sequence of events is observed in vitro in the non-contracting human skin equivalent (HSE) which was developed in this lab (1). As a part of the definition process for this model of living skin we are examining its ultrastructural features. Since desmosomes are important in maintaining cell-cell interactions in stratified epithelia their distribution in HSE was examined.


Author(s):  
F.T. Llados ◽  
V. Krlho ◽  
G.D. Pappas

It Is known that Ca++ enters the muscle fiber at the junctional area during the action of the neurotransmitter, acetylcholine (ACh). Pappas and Rose demonstrated that following Intense stimulation, calcium deposits are found In the postsynaptic muscle membrane, Indicating the existence of calcium uptake In the postsynaptic area following ACh release. In addition to this calcium uptake, when mammal Ian skeletal muscles are exposed to a sustained action of the neurotransmitter, muscle damage develops. These same effects, l.e., Increased transmitter release, calcium uptake and finally muscle damage, can be obtained by Incubating the muscle with lonophore A23178.


Sign in / Sign up

Export Citation Format

Share Document