Effect of reflex therapy on time course of ultrastructural changes in muscular branches of the brachial plexus

1987 ◽  
Vol 103 (1) ◽  
pp. 128-130
Author(s):  
A. M. Zagrebin ◽  
O. A. Khonny ◽  
V. M. Chuchkov ◽  
A. V. Isaev ◽  
T. B. Shirokova
Keyword(s):  
Brachial Plexus ◽  
Time Course ◽  
Ultrastructural Changes ◽  
Reflex Therapy

Ultrastructural Changes of the Symbiotic Chlorella-Like Alga Isolated from Hydra Viridis

1982 ◽  
Vol 40 ◽  
pp. 320-321
Author(s):  
K.W. Lee ◽  
R.H. Meints ◽  
D. Kuczmarski ◽  
J.L. Van Etten
Keyword(s):  
Time Course ◽  
Reciprocal Cross ◽  
Ultrastructural Level ◽  
Ultrastructural Changes ◽  
Symbiotic Relationship ◽  
Cell Recognition ◽  
Green Hydra ◽  
Different Strains ◽  
Hydra Viridis

The physiological, biochemical, and ultrastructural aspects of the symbiotic relationship between the Chlorella-like algae and the hydra have been intensively investigated. Reciprocal cross-transfer of the Chlorellalike algae between different strains of green hydra provide a system for the study of cell recognition. However, our attempts to culture the algae free of the host hydra of the Florida strain, Hydra viridis, have been consistently unsuccessful. We were, therefore, prompted to examine the isolated algae at the ultrastructural level on a time course.

scholarly journals Comparative Time-Course Physiological Responses and Proteomic Analysis of Melatonin Priming on Promoting Germination in Aged Oat (Avena sativa L.) Seeds

2021 ◽  
Vol 22 (2) ◽  
pp. 811
Author(s):  
Huifang Yan ◽  
Peisheng Mao
Keyword(s):  
Antioxidant Capacity ◽  
Avena Sativa ◽  
Proteomic Analysis ◽  
Time Course ◽  
Intact Cell ◽  
Membrane Integrity ◽  
Acid Synthesis ◽  
Ultrastructural Changes ◽  
Oat Seeds ◽  
Aged Seeds

Melatonin priming is an effective strategy to improve the germination of aged oat (Avena sativa L.) seeds, but the mechanism involved in its time-course responses has remained largely unknown. In the present study, the phenotypic differences, ultrastructural changes, physiological characteristics, and proteomic profiles were examined in aged and melatonin-primed seed (with 10 μM melatonin treatment for 12, 24, and 36 h). Thus, 36 h priming (T36) had a better remediation effect on aged seeds, reflecting in the improved germinability and seedlings, relatively intact cell ultrastructures, and enhanced antioxidant capacity. Proteomic analysis revealed 201 differentially abundant proteins between aged and T36 seeds, of which 96 were up-accumulated. In melatonin-primed seeds, the restoration of membrane integrity by improved antioxidant capacity, which was affected by the stimulation of jasmonic acid synthesis via up-accumulation of 12-oxo-phytodienoic acid reductase, might be a candidate mechanism. Moreover, the relatively intact ultrastructures enabled amino acid metabolism and phenylpropanoid biosynthesis, which were closely associated with energy generation through intermediates of pyruvate, phosphoenolpyruvate, fumarate, and α-ketoglutarate, thus providing energy, active amino acids, and secondary metabolites necessary for germination improvement of aged seeds. These findings clarify the time-course related pathways associated with melatonin priming on promoting the germination of aged oat seeds.

scholarly journals Particle Assembly and Ultrastructural Features Associated with Replication of the Lytic Archaeal Virus Sulfolobus Turreted Icosahedral Virus

2009 ◽  
Vol 83 (12) ◽  
pp. 5964-5970 ◽  
Author(s):  
Susan K. Brumfield ◽  
Alice C. Ortmann ◽  
Vincent Ruigrok ◽  
Peter Suci ◽  
Trevor Douglas ◽  
...  
Keyword(s):  
Time Course ◽  
Plaque Assay ◽  
Ultrastructural Changes ◽  
Progeny Virus ◽  
Particle Assembly ◽  
Virus Particles ◽  
Transmission Electron ◽  
Archaeal Viruses ◽  
Infected Cells ◽  
Sulfolobus Turreted Icosahedral Virus

ABSTRACT Little is known about the replication cycle of archaeal viruses. We have investigated the ultrastructural changes of Sulfolobus solfataricus P2 associated with infection by Sulfolobus turreted icosahedral virus (STIV). A time course of a near synchronous STIV infection was analyzed using both scanning and transmission electron microscopy. Assembly of STIV particles, including particles lacking DNA, was observed within cells, and fully assembled STIV particles were visible by 30 h postinfection (hpi). STIV was determined to be a lytic virus, causing cell disruption beginning at 30 hpi. Prior to cell lysis, virus infection resulted in the formation of pyramid-like projections from the cell surface. These projections, which have not been documented in any other host-virus system, appeared to be caused by the protrusion of the cell membrane beyond the bordering S-layer. These structures are thought to be sites at which progeny virus particles are released from infected cells. Based on these observations of lysis, a plaque assay was developed for STIV. From these studies we propose an overall assembly model for STIV.

Cellular differentiation in Venturia inaequalis ascospores during germination and penetration of apple leaves

1987 ◽  
Vol 65 (12) ◽  
pp. 2549-2561 ◽  
Author(s):  
K. J. Smereka ◽  
W. E. Machardy ◽  
A. P. Kausch
Keyword(s):  
Time Course ◽  
Venturia Inaequalis ◽  
Ultrastructural Changes ◽  
Wall Material ◽  
Dense Matrix ◽  
Mechanical Pressure ◽  
Selective Staining ◽  
Infection Hypha ◽  
Dome Shape ◽  
Host Tissues

The penetration of the apple leaf cuticle by ascospores of Venturia inaequalis was studied by using ultrastructural and cytochemical techniques. A time-course developmental sequence is presented. Attachment of ascospores to the leaf surface appears to be by a mucilaginous substance and is followed by germination and penetration pore formation. The penetration pore is a circular opening adjacent to the leaf. It appears to form by degradation of the fungal wall and is bordered by a thickening of fungal wall material. Above the penetration pore, an infection sac forms from invagination and extension of the fungal plasmalemma. This structure has been reported only in V. inaequalis. Infection sac development initiates when the fungal plasmalemma appears to be forced into a dome shape. The dome flattens out and the membrane folds back upon itself, circumscribing the margin of the pore. The folded membrane becomes apposed, resulting in a circular belt of junctional structures which morphologically resemble molluscan septate junctions. As the infection sac enlarges, additional junctions form wherever the infection sac membrane abuts with the fungal plasmalemma. Selective staining with phosphotungstic acid revealed that the infection sac membrane becomes differentiated from the fungal plasmalemma. The infection sac enlarges and accumulates a dense matrix that appears to penetrate into the cuticle, causing ultrastructural changes in host tissues. The infection hypha, which is an extension of the infection sac membrane, breaches the cuticle without any apparent mechanical pressure.

The Developing Shoulder Has a Limited Capacity to Recover After a Short Duration of Paralysis

2012 ◽  
Author(s):  
Ryan Potter ◽  
Stavros Thomopoulos
Keyword(s):  
United States ◽  
Brachial Plexus ◽  
Short Duration ◽  
Time Course ◽  
The United States ◽  
Limited Capacity ◽  
Functional Deficits ◽  
Shoulder Paralysis ◽  
Functional Defects

Neonatal brachial plexus injuries during childbirth can cause shoulder paralysis in 1 out of every 250 births in the United States.1,2 Although 80% of these infants recover spontaneously and have no residual complications, a number of them have persistent paralysis and functional deficits.1,3,4 Surgeons are thus faced with a choice on if and when to intervene. However, the time course of persistent paralysis leading to permanent functional defects in the neonate is unclear.

Time course of functional repair of the alveolar epithelium after hyperoxic injury

1992 ◽  
Vol 73 (5) ◽  
pp. 1881-1887 ◽  
Author(s):  
R. M. Palazzo ◽  
O. D. Wangensteen ◽  
D. E. Niewoehner
Keyword(s):  
Time Course ◽  
Alveolar Epithelium ◽  
Fluorescein Isothiocyanate ◽  
Acute Injury ◽  
Ultrastructural Changes ◽  
Epithelial Permeability ◽  
Major Barrier ◽  
Alveolar Epithelial ◽  
Hyperoxic Exposure ◽  
Perfused Lung

The alveolar epithelium is the major barrier to solute and protein flux between the pulmonary vascular bed and the airspaces. Hyperoxic exposure increases epithelial permeability, and during recovery, normal permeability must be regained. To determine the time course for recovery of this function, we exposed hamsters to > 95% O2 for 4.5 days and returned them to room air. After recovery periods of 0.5, 1, 3, 7, and 14 days, alveolar epithelial permeability x surface area (PS) values for [14C]sucrose and fluorescein isothiocyanate-Dextran 20 were measured with isolated perfused lung techniques. Eighty-five percent of the exposed animals survived in room air. Control PS values for sucrose and Dextran 20 were 5.76 x 10(-5) and 0.29 x 10(-5) cm3/s, respectively. After hyperoxia both values were increased by a factor of five. After 0.5 days of recovery, PS remained elevated, but after 1 day they were decreased. Normal PS values were achieved after 3 days for sucrose and 7 days for Dextran 20. During both acute injury and recovery, epithelial selectivity was unchanged and no ultrastructural changes in the alveolar epithelium were observed.

Heptatic Response to Hyperthermia

1980 ◽  
Vol 38 ◽  
pp. 450-451
Author(s):  
W. D. Bowers ◽  
R. Hubbard ◽  
P. Chisholm ◽  
M. Murphy ◽  
P. Williams
Keyword(s):  
Time Course ◽  
Ultrastructural Changes ◽  
Cellular Injury ◽  
Common Site ◽  
Time Intervals ◽  
Normal Cells ◽  
Precise Control ◽  
Hyperthermic Treatment ◽  
Rat Livers ◽  
Isolated Rat

Pettigrew et al. (1) proposed that above 41.8° C normal cells were subject to hyperthermic injury while at or below this temperature no serious cellular injury occurred. Cancer patients were maintained at this temperature for several hours, with little evidence of injury, in efforts to kill the more heat sensitive cancer cells. Inherent in this treatment regime was the theory that the duration of hyperthermic treatment at or below 41.8°C had no impact on injury to normal cells. Previous work in our laboratory, using the time course of enzyme leakage from isolated rat livers perfused with KRB at 37° C-43° C for 90 min, suggested that injury followed a time/temperature relationship. Ultrastructural, histological, and enzymatic data indicated that injury could occur below 41.8°C. Electron microscopy revealed celluar injury in livers which appeared normal by light microscopy. The time at which ultrastructural changes occurred at specific temperatures could not be determined since specimens were taken at the end of the perfusion experiments. In this study, livers were perfused for varing time intervals at temperatures from 41° C to 43° C, and these were compared with control livers perfused at 37° C for 90 min. The liver was chosen for this study because it is a common site of injury in both heatstroke and hyperthermic therapy. In addition, perfusion allows precise control of the organ's environment.

scholarly journals Morphometric analysis of the ultrastructural changes in rat liver induced by the peroxisome proliferator SaH 42-348.

1976 ◽  
Vol 71 (3) ◽  
pp. 768-780 ◽  
Author(s):  
D E Moody ◽  
J K Reddy
Keyword(s):  
Surface Density ◽  
Time Course ◽  
Liver Weight ◽  
Relative Volume ◽  
Male Rats ◽  
Ultrastructural Changes ◽  
Peroxisome Proliferator ◽  
Moderate Increase ◽  
Hepatic Lobule ◽  
Rapid Reduction

The changes occurring in hepatocytes of F-344 male rats during a 3-wk treatment with a hypolipidemic agent, 1-methyl-4-piperidyl-bis [p-chlorophenoxy]acetate (SaH 42-348), have been evaluated by morphometric and biochemical methods. The twofold increase in liver weight resulted from a significant increase in hepatocyte cytoplasm as well as a moderate increase in the number of liver cells. The peroxisome population and SER played an overwhelming part in the hypertrophy of hepatocytic cytoplasm. The relative volume and the surface density of peroxisomes volume resulted from an increased ninefold and sevenfold, respectively. The increase in the collective peroxisome volume resulted from an increase in both the number and the average volume of peroxisomes. The SER also demonstrated a substantial increase in these values. The relative volume and surface density of mitochondria were not significantly altered in comparison to controls, while these values for RER decreased onefold. Studies on the lobular distribution of cytoplasmic organelles before and during treatment revealed that the relative volume and surface density of peroxisomes and SER increased from periportal to centrilobular cells of the hepatic lobule, whereas mitochondrial values decreased from periportal to centrilobular cells. The RER values were fairly constant in different parts of the hepatic lobule. The increase in peroxisome and SER volume and surface area was first evident within the first 3 days of SaH 42-348 treatment and these values continued to increase, reaching a steady state within 2 wk. The time course of increase in catalase and carnitine acetyltransferase activities correlated with the morphometric data on the peroxisomes. After cessation of SaH 42-348 treatment, the peroxisome values decreased rapidly within the first 3 days and reached control levels within 1 wk. Moderate reduction in SER values occurred after withdrawal of the drug, but these values remained higher than controls even after 2 wk, suggesting that the reduction in the amount of circulating peroxisome proteins may result in empty SER channels. On the 4th day of drug withdrawal a significant increase in the relative volume and surface density of lysosomes was observed, suggesting that these organelles may play some part in the removal of cellular membranes. However, the rapid reduction in peroxisome values after SaH 42-348 withdrawal appears to be due to cessation of enhanced peroxisome protein synthesis.

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