HISTOMETRIC AND ULTRASTRUCTURAL ORGANIZATION OF THE NERVIMUSCULAR TERMINALS OF SKELETAL MUSCLES AT A HYPOKINESIA

2019 ◽  
pp. 55-63
Author(s):  
Z. M. Yaschyshyn ◽  
S. L. Popel
Keyword(s):  
Skeletal Muscles ◽  
Structural Adjustment ◽  
Muscle Fibers ◽  
Electron Microscopic Examination ◽  
Nerve Fibers ◽  
Ultrastructural Changes ◽  
Ultrastructural Organization ◽  
Electron Microscopic ◽  
Myelinated Nerve ◽  
Male Wistar Rats

The aim: to study the dynamics of histological and ultrastructural changes in muscle fibers and their neuromuscular endings under conditions of prolonged hypokinesia at different stages of ontogenesis. Methods. Studied skeletal muscles and their peripheral nervous apparatus of laboratory male Wistar rats aged 30 to 270 days. The restriction of motor activity was carried out in special canister cells for 30, 60, 90, and 240 days (5 animals for each term). To determine the type of muscle fiber, the Nahlas histochemical method was used, the Kulchitsky method was used to detect myelinated nerve fibers, the Bilshovsky-Gros method and the electron microscopic method to identify neuromuscular endings. Results. The data of histological and electron microscopic examination of skeletal muscle fibers and their neuromuscular endings under conditions of prolonged hypokinesia indicate their regular restructuring during the development of muscles, the formation of their synapses and structures that are associated with them at different stages of ontogenesis. Conclusion. The study provides an in-depth understanding of the relative frequency and nature of the disturbance of the neuromuscular endings during prolonged hypokinesia and its effect on the dynamics of structural adjustment of individual types of muscle fibers in ontogenesis.

HISTOMETRIC AND ULTRASTRUCTURAL ORGANIZATION OF THE NERVIMUSCULAR TERMINALS OF SKELETAL MUSCLES AT A HYPOKINESIA

2019 ◽  
pp. 55-63
Author(s):  
Z. M. Yaschyshyn ◽  
S. L. Popel
Keyword(s):  
Skeletal Muscles ◽  
Structural Adjustment ◽  
Muscle Fibers ◽  
Electron Microscopic Examination ◽  
Nerve Fibers ◽  
Ultrastructural Changes ◽  
Ultrastructural Organization ◽  
Electron Microscopic ◽  
Myelinated Nerve ◽  
Male Wistar Rats

The aim: to study the dynamics of histological and ultrastructural changes in muscle fibers and their neuromuscular endings under conditions of prolonged hypokinesia at different stages of ontogenesis. Methods. Studied skeletal muscles and their peripheral nervous apparatus of laboratory male Wistar rats aged 30 to 270 days. The restriction of motor activity was carried out in special canister cells for 30, 60, 90, and 240 days (5 animals for each term). To determine the type of muscle fiber, the Nahlas histochemical method was used, the Kulchitsky method was used to detect myelinated nerve fibers, the Bilshovsky-Gros method and the electron microscopic method to identify neuromuscular endings. Results. The data of histological and electron microscopic examination of skeletal muscle fibers and their neuromuscular endings under conditions of prolonged hypokinesia indicate their regular restructuring during the development of muscles, the formation of their synapses and structures that are associated with them at different stages of ontogenesis. Conclusion. The study provides an in-depth understanding of the relative frequency and nature of the disturbance of the neuromuscular endings during prolonged hypokinesia and its effect on the dynamics of structural adjustment of individual types of muscle fibers in ontogenesis.

scholarly journals ULTRASTRUCTURAL ORGANIZATION OF OBLIQUELY STRIATED MUSCLE FIBERS IN ASCARIS LUMBRICOIDES

1965 ◽  
Vol 25 (3) ◽  
pp. 495-515 ◽  
Author(s):  
Jack Rosenbluth
Keyword(s):  
Plasma Membrane ◽  
Striated Muscle ◽  
Muscle Fibers ◽  
Electron Microscopic Examination ◽  
Thick Filament ◽  
Ultrastructural Organization ◽  
Striated Muscles ◽  
Three Dimensional Model ◽  
Electron Microscopic ◽  
Thin Filaments

The somatic musculature of the nematode, Ascaris, is currently thought to consist of smooth muscle fibers, which contain intracellular supporting fibrils arranged in a regular pattern. Electron microscopic examination shows that the muscle fibers are, in fact, comparable to the striated muscles of vertebrates in that they contain interdigitating arrays of thick and thin myofilaments which form H, A, and I bands. In the A bands each thick filament is surrounded by about 10 to 12 thin filaments. The earlier confusion about the classification of this muscle probably arose from the fact that in one longitudinal plane the myofilaments are markedly staggered and, as a result, the striations in that plane of section are not transverse but oblique, forming an angle of only about 6° with the filament axis. The apparent direction of the striations changes with the plane of the section and may vary all the way from radial to longitudinal. A three-dimensional model is proposed which accounts for the appearance of this muscle in various planes. Z lines as such are absent but are replaced by smaller, less orderly, counterpart "Z bundles" to which thin filaments attach. These bundles are closely associated with fibrillar dense bodies and with deep infoldings of the plasma membrane. The invaginations of the plasma membrane together with intracellular, flattened, membranous cisternae form dyads and triads. It is suggested that these complexes, which also occur at the cell surface, may constitute strategically located, low-impedance patches through which local currents are channeled selectively.

scholarly journals Ultrastructural organization of hemomicrocirculatory bed of the lungs affected by Doxorubicin

2019 ◽  
Vol 25 (3) ◽  
pp. 58-62
Author(s):  
L.M. Zaiats ◽  
O.O. Yankiv ◽  
I.V. Gunas ◽  
O.M. Shapoval ◽  
O.V. Shypitsina
Keyword(s):  
Endothelial Cells ◽  
Rheological Properties ◽  
Electron Microscopic Examination ◽  
Ultrastructural Changes ◽  
Control Group ◽  
Ultrastructural Organization ◽  
Alveolar Wall ◽  
Electron Microscopic ◽  
Pulmonary Tissue ◽  
Submicroscopic Structure

One of the most effective anticancer drugs for breast cancer, lymphoma, soft tissue sarcoma, leukemia, some solid tumors is Doxorubicin. However, its antitumor effect directly correlates with the dose-dependent manifestation of toxicity to healthy tissues and body systems. The purpose of the study is to study the dynamics of ultrastructural changes of the hemomicrocirculatory bed under the influence of Doxorubicin. Animals were divided into 3 groups: I – intact rats (n=10); II – control (n=20); III – rats with Doxorubicin model (n=40). Doxorubicin was administered intraperitoneally at a dose of 5 mg/kg body weight once a week for 4 weeks. An animal control group was intraperitoneally injected with an equivalent volume of saline. Pulmonary tissue sampling for electron microscopic examination was performed under thiopental anesthesia 7, 14, 21, 28 days after the start of the experiment. Pieces of pulmonary tissue were fixed in 2.5% glutaraldehyde followed by fixation in 1% osmium tetroxide. After dehydration, the material was poured into araldite-epon. The sections obtained on a “Tesla BS-490” ultramicrotome were examined in an electron microscope “PEM-125K”. It is established that within 7 days after the first injection of Doxorubicin in the lungs changes in the structural organization of the hemomicrocapillary bed and the disturbance of blood rheological properties are determined, as evidenced by the excessive accumulation of neutrophils in the hemocapillaries, their adhesion and aggregation. With the extension of the study period (14-28 days) there is a progressive disturbance of the submicroscopic structure of hemocapillaries of the alveolar wall and marked changes in the rheological properties of blood. In endothelial cells, swelling phenomena with organelle disorganization are determined, and in some areas there is a desquamation of endothelial cells into the lumen of the hemocapillaries with basal membrane exposures. In the lumen of the microvessels, red blood cells and leuco-platelet aggregates are noted. Thus, the introduction of Doxorubicin leads to pronounced submicroscopic changes in the hemomicrocirculatory bed. Violation of the ultrastructural organization of the hemomicrocirculatory bed of the lungs is determined after 7 days after the start of the study.

Effects of Combination Chemical Peel on Facial Photodamaged Skin

1998 ◽  
Vol 15 (3) ◽  
pp. 263-271 ◽  
Author(s):  
May H. El Samahy ◽  
Mohamed M. Ghoz ◽  
Naglaa Ramzy
Keyword(s):  
Glycolic Acid ◽  
Electron Microscopic Examination ◽  
Ultrastructural Changes ◽  
Elastic Fibers ◽  
Electron Microscopic ◽  
Trichloracetic Acid ◽  
Age Related ◽  
Photodamaged Skin ◽  
Microscopic Studies ◽  
Activated Fibroblasts

Introduction: Chemical peeling involves the topical application of a wounding agent with the goal of effecting an organized regeneration of the skin. The histologic and ultrastructural features of actinic and age-related damage include structural abnormalities that disrupt normal epidermal and dermal architecture. The purpose of the present study is to evaluate the clinical and histologic effects of an enhanced medium-depth peel on photodamaged skin. We aimed to correlate the clinical and histologic findings with the ultrastructural changes occurring after the peel. These ultrastructural features are supposed to be more precise and informative than the clinical or histological response. They may also be employed as markers of peel response. Materials and Methods: In the present study, five patients with actinically damaged skin underwent enhanced medium-depth peels using 70% glycolic acid and 35% trichloracetic acid. Biopsy specimens were taken before the peel and 3 months after the peel for histologic and electron microscopic examination. Results: Clinical resolution of actinic damage corresponded with restoration of epidermal polarity. Characteristic histologic and ultrastructural features of the skin after peeling include markedly decreased epidermal intracytoplasmic vacuoles, decreased elastic fibers, increased activated fibroblasts, and organized parallel arrays of collagen fibrils. The diameters of individual fibrils are consistent with recent production of collagen by activated fibroblasts. Conclusion: Glycolic acid—tricholoro-acetic acid (GA-TCA) is an effective combination for a medium-depth peel in photodamaged skin both clinically and histologically. Electron microscopic studies following medium-depth peels reveal changes more profound than those seen histologically. The characteristic changes occurring in the keratinocytes, collagen, and elastic fibrils may be considered as guidelines or markers of the peel response.

A light and electron microscopic examination of muscles in the walking legs of the horseshoe crab, Limulus polyphemus (L.)

1972 ◽  
Vol 50 (11) ◽  
pp. 1447-1455 ◽  
Author(s):  
C. R. Fourtner ◽  
R. G. Sherman
Keyword(s):  
Skeletal Muscles ◽  
Horseshoe Crab ◽  
Sarcomere Length ◽  
Electron Microscopic Examination ◽  
Limulus Polyphemus ◽  
Electron Microscopic ◽  
Mean Values ◽  
Transverse Tubular System ◽  
Leg Muscles ◽  
Uniform Population

An examination was made of the gross morphology and ultrastructure of skeletal muscles in the legs of the horseshoe crab, Limulus polyphemus (L.). The origins, insertions, actions, and innervation of each head of the seven distal leg muscles are described. A detailed description of the transverse tubular system and the sarcoplasmic reticulum is also given. Of special interest is the possibility that the muscle fibers may be split into "units" of different diameters.The sarcomere length of fibers in the seven muscles was determined to see if both long and short sarcomere length fibers are present. The distribution of fiber sarcomere lengths in each muscle is unimodal, and mean values for each of the different muscles range from 7.6 to 8.5 μ. The ultrastructural features of fibers in each muscle also are similar. Therefore, it appears that horseshoe crab leg skeletal muscles are composed structurally of a fairly uniform population of fibers and that fast and slow categories of fibers, at least as defined for other arthropods, are not present in the horseshoe crab muscles studied here.

scholarly journals Light Microscopic and Ultrastructural Changes in the Ceca of Chicks Inoculated with Human and Canine Serpulina pilosicoli

1996 ◽  
Vol 33 (5) ◽  
pp. 542-550 ◽  
Author(s):  
N. Muniappa ◽  
G. E. Duhamel ◽  
M. R. Mathiesen ◽  
T. W. Bargar
Keyword(s):  
Brush Border ◽  
Microscopic Examination ◽  
Electron Microscopic Examination ◽  
Ultrastructural Changes ◽  
Surface Epithelium ◽  
Post Inoculation ◽  
Human Beings ◽  
Control Groups ◽  
Electron Microscopic ◽  
Terminal Web

Light microscopic and ultrastructural changes were observed in chicks challenged with North American Serpulina pilosicoli, a weakly β-hemolytic intestinal spirochete (WBHIS) associated with human and canine intestinal spirochetosis. Chicks in control groups received trypticase soy broth or canine Serpulina innocens. The birds were necropsied at weekly intervals, and the ceca were processed for bacteriologic and pathologic examinations. No WBHIS were isolated from the ceca of chicks in the control groups, but WBHIS with genotypes similar to the parent isolates were isolated from the ceca of chicks inoculated with human and canine S. pilosicoli. Gross examination revealed no significant changes in the ceca of chicks at any time post-inoculation. Light microscopic examination revealed no spirochetal attachment in the ceca of chicks in control groups. In contrast, focal to diffuse thickening of the brush border of the surface epithelium along with dilation of the crypt lumina and mild focal lamina propria heterophil infiltration were present in the ceca of chicks inoculated with human and canine S. pilosicoli. Scanning electron microscopic examination revealed focal to confluent spirochetal attachment mainly in the furrow region at the periphery of the crypt units. Transmission electron microscopic examination revealed spirochetes attached to the brush border of the cecal epithelium, causing effacement of the microvilli and disruption of the terminal web microfilaments. The cecal epithelium of chicks inoculated with the canine S. pilosicoli also had caplike elevations of the apical membrane at the point of attachment of the spirochetes together with large numbers of vesicles in the cytoplasm immediately beneath the terminal web and evidence of spirochetal invasion beyond the mucosal barrier. The changes observed suggested that the mechanism of attachment of human and canine S. pilosicoli to the cecal epithelium of chicks was analogous to but different from that described previously for other attaching and effacing gastroenteric bacterial pathogens of human beings and animals.

scholarly journals Beneficial effect of genistein on lowering blood pressure and kidney toxicity in fructose-fed hypertensive rats

2012 ◽  
Vol 109 (10) ◽  
pp. 1806-1812 ◽  
Author(s):  
Nallasamy Palanisamy ◽  
Anuradha C. Venkataraman
Keyword(s):  
Blood Pressure ◽  
Structural Changes ◽  
Ultrastructural Changes ◽  
Hypertensive Rats ◽  
Enos Expression ◽  
Electron Microscopic ◽  
Plasma Angiotensin ◽  
Enhanced Expression ◽  
Male Wistar Rats ◽  
Microscopic Studies

The study evaluates the effects of genistein on blood pressure (BP) and ultrastructural changes in kidney of fructose-fed hypertensive rats. Male Wistar rats were fed a diet containing 60 % starch or 60 % fructose as the source of carbohydrate. After 15 d, rats in each dietary group were divided into two groups and were treated with either genistein (1 mg/kg per d) in dimethylsulfoxide (DMSO) or 30 % DMSO alone. BP, pressor mechanisms, protein kinase C-βII (PKC-βII) expression, endothelial NO synthase (eNOS) expression and renal ultrastructural changes were evaluated after 60 d. Fructose-fed rats displayed significant elevation in BP and heart rate. Significant increase in plasma angiotensin-converting enzyme (ACE) activity, alterations in renal lipid profile, nitrite and kallikrein activity, enhanced expression of membrane-associated PKC-βII and decreased expression of eNOS were observed in them. Histology and electron microscopic studies showed structural changes in the kidney. Genistein administration lowered BP, restored ACE, PKC-βII and eNOS expression and preserved renal ultrastructural integrity. These findings demonstrate that genistein has effects on eNOS activity in renal cells, leading to eNOS activation and NO synthesis. These effects could have been mediated by activation of PKC-βII. The observed benefits of genistein make it a promising candidate for therapy of diabetic kidney disease.

scholarly journals The Morphological Assessment of Rats` Liver after the Introduction of the Nucleoside Reverse Transcriptase Inhibitor of Azidothymidine

2019 ◽  
pp. 61-67
Author(s):  
M. N. Kurbat ◽  
R. I. Kravchuk ◽  
O. B. Ostrovskaya
Keyword(s):  
Nucleoside Reverse Transcriptase Inhibitor ◽  
Structural Changes ◽  
Electron Microscopic Examination ◽  
Transcriptase Inhibitor ◽  
Ultrastructural Changes ◽  
Electron Microscopic ◽  
Structural And Functional Properties ◽  
Hepatotoxic Effect ◽  
Reverse Transcriptase Inhibitor ◽  
Morphological Assessment

Objective: to study the microscopic and ultrastructural changes in the liver of rats exposed to AZT. Material and methods. The histological and electron microscopic examination of the liver samples with mitochondrial morphometry has been performed. Results . The 7-day administration of AZT does not cause any significant structural changes in the liver. The exposure to the drug for 21 days leads to the development of moderate inflammatory and degenerative processes in the liver, including changes in the structure of hepatocyte mitochondria. Conclusion. One of the pathogenetic mechanisms of the hepatotoxic effect of AZT is its impact on the structural and functional properties of hepatocyte mitochondria.

scholarly journals Hysto-ultrastructure of the facial nerve and mimic muscles in the norm and in the conditions of eхperimental neuropathy

2017 ◽  
Vol 8 (4) ◽  
pp. 569-576
Author(s):  
V. Myhailiuk ◽  
I. Mykhailiuk ◽  
M. Hembarovskyi ◽  
O. Lebid ◽  
K. Duda ◽  
...  
Keyword(s):  
Facial Nerve ◽  
Morphological Changes ◽  
Motor Nerve ◽  
Muscle Fibers ◽  
Small Diameter ◽  
Nerve Fibers ◽  
Residual Effects ◽  
Myelinated Nerve ◽  
Fine Grained ◽  
Argyrophilic Grains

We studied the structural components of the facial nerve in the norm and with cold neuropathy, indicating morphological changes in neuromuscular endings and muscle fibers at 10, 15, 30 and 60 days from the beginning of the simulation of experimental neuropathy, which was caused by local supercooling of the projection portions of the extracranial parts of the facial nerve on the background of the preliminary introduction of Freud’s complete adjuvant. We established that the pathomorphological changes in the endonevral microcirculatory bed have a phase character: the initial spasm (up to 10 days) changes in paralytic vasodilation, and its residual effects remain until the end of the experiment (60 days). Changes in hemomicrocirculation conditions lead to marked disturbances in the structure of myelinic nerve fibers, which have the character of segmental demyelination with signs of delay in axonal transport and reactive restructuring of neuromuscular endings. The change in the metric composition of myelinated nerve fibers is due to an increase in the number of nerve fibers of medium and large diameters (up to 30 days) and small diameter (after 30 days). In different periods of the experiment, a decrease in the branching area of the terminal branches of the motor axon is observed in the nerve cells, local edema of the endonevria, degenerative changes in a part of the nerve fibers develop. Due to the fine-grained decay of the final nerve branches, degeneration of the motor endings took place two weeks after the start of the experiment. Neuropathy for 30 days caused a pronounced inhibition of spotting in the peripheral parts of the motor nerve fibers. After 60 days of experiment, a large number of muscle fibers underwent destructive changes. The size of a significant part of the neuromuscular endings was reduced. In all terms of cold neuropathy, neurolematocytes reacted in the same way: cytoplasm was swollen, argyrophilic grains appeared in the nuclei, fine-grained decay of individual nuclei occurred. 

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