Effect of thyrocalcitonin and hypoxia on DNA synthesis in connective-tissue cells of the regenerating skin

1977 ◽  
Vol 84 (5) ◽  
pp. 1646-1649
Author(s):  
G. V. Khomullo ◽  
T. V. Ivanenko ◽  
V. I. Lotova
Diabetes ◽  
1991 ◽  
Vol 40 (5) ◽  
pp. 605-611 ◽  
Author(s):  
P. Muona ◽  
J. Peltonen ◽  
S. Jaakkola ◽  
J. Uitto

1973 ◽  
Vol 57 (3) ◽  
pp. 743-759 ◽  
Author(s):  
Charles K. Jablecki ◽  
John E. Heuser ◽  
Seymour Kaufman

Work-induced growth of rat soleus muscle is accompanied by an early increase in new RNA synthesis. To determine the cell type(s) responsible for the increased RNA synthesis, we compared light autoradiographs of control and hypertrophying muscles from rats injected with tritiated uridine 12, 24, and 48 h after inducing hypertrophy. There was an increased number of silver grains over autoradiographs of hypertrophied muscle. This increase occurred over connective tissue cells; there was no increase in the number of silver grains over the muscle fibers. Quantitative studies demonstrated that between 70 and 80% of the radioactivity in the muscle that survived fixation and washing was in RNA. Pretreatment of the animals with actinomycin D reduced in parallel both the radioactivity in RNA and the number of silver grains over autoradiographs. Proliferation of the connective tissue in hypertrophying muscle was evident in light micrographs, and electron micrographs identified the proliferating cells as enlarged fibroblasts and macrophages; the connective tissue cells remained after hypertrophy was completed. Thus, proliferating connective tissue cells are the major site of the increase in new RNA synthesis during acute work-induced growth of skeletal muscle. It is suggested that in the analysis of physiological adaptations of muscle, the connective tissue cells deserve consideration as a site of significant molecular activity.


1916 ◽  
Vol 24 (6) ◽  
pp. 683-688 ◽  
Author(s):  
Robert A. Lambert

The comparative resistance of bacteria and human tissue cells to antiseptics and other chemicals may be easily tested by tissue cultures under conditions which approximate those found in the living body. A comparative study shows that while human cells (connective tissue and wandering cells) are highly resistant to many antiseptics, they are in general more easily killed than bacteria (Staphylococcus aureus). Of the antiseptics tested, which include mercuric chloride, iodine, potassium mercuric iodide, phenol, tricresol, hydrogen peroxide, hypochlorites (Dakin's solution), argyrol, and alcohol, the one which approaches most closely the ideal disinfectant is iodine, which kills bacteria in strengths that do not seriously injure connective tissue cells or wandering cells.


1992 ◽  
Vol 163 (1) ◽  
pp. 345-358 ◽  
Author(s):  
P. M.J. SHELTON ◽  
R. O. STEPHEN ◽  
J. J.A. SCOTT ◽  
A. R. TINDALL

The mechanical connections of the metathoracic femoral chordotonal organ (mtFCO) with its insertion at the femoro-tibial joint are described. The apodeme complex is shown to consist of a distal cuticular rod that is replaced proximally by dorsal and ventral ligaments. The dorsal ligament is a direct continuation of the distal rod but proximally it is replaced by ligamentous cells. The ventral ligament has no cuticular core and consists of ligamentous cells throughout its length. The ligaments are composed of bundles of connective tissue cells that are each enclosed in an extracellular matrix containing acid-fuchsin-staining fibrils. Internally the cells are packed with microtubules. During extension and flexion of the joint, the two ligaments move differentially. During passive extension of the tibia, the ventral ligament remains taut but the dorsal one buckles to form a slack loop. Direct observation of living preparations shows that the loop is first detectable during extension of the tibia at joint angles greater than about 51°. During flexion, the loop gradually tightens and disappears. It has completely disappeared at joint angles of less than about 36°. Changes in loop shape were demonstrable using preparations in which the tibia was moved sinusoidally ±10° about a mean femoro-tibial angle of 90° and photographs were taken using phase-locked illumination. Other details of the apodeme complex are described and the significance of the findings is discussed in relation to mtFCO function.


Author(s):  
M Muthu Rama Krishnan ◽  
Pratik Shah ◽  
Madhumala Ghosh ◽  
Mousumi Pal ◽  
Chandan Chakraborty ◽  
...  

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