STIMULATION OF CELLS BY INTENSE FLASHES OF ULTRAVIOLET LIGHT

A study has been made of the effect of sudden intense flashes of ultraviolet light, acting on a wide variety of cells and tissues, with special reference to stimulation. The flashes are obtained by a high voltage condenser discharge through a quartz mercury vapor sterilamp, using the method of Rentschler. The lethal effect of a single such discharge is widespread among unicellular organisms. Medullated nerves and whole muscles are not visibly stimulated, because of absorption by connective tissue. Single muscle fibers undergo immediate contracture in 50 per cent of the experiments. Nitella cells are stimulated, the effect depending on the dosage. Weak ultraviolet flashes slow or stop cyclosis reversibly. Strong flashes stop cyclosis reversibly with the appearance of a local or a propagated action potential. Very strong flashes kill the Nitella cells. The effect of single flashes on myonemes, oscillatory movement, ameboid movement, cilia, flagella, and bioluminescence is described in the text.

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RESULTS OF IRRADIATING STAPHYLOCOCCUS AUREUS BACTERIOPHAGE WITH MONOCHROMATIC ULTRAVIOLET LIGHT

Journal of Experimental Medicine ◽

10.1084/jem.60.2.179 ◽

1934 ◽

Vol 60 (2) ◽

pp. 179-188 ◽

Cited By ~ 24

Author(s):

Frederick L. Gates

Keyword(s):

Staphylococcus Aureus ◽

Energy Level ◽

Ultraviolet Light ◽

Mercury Vapor ◽

Lytic Activity ◽

Striking Similarity ◽

Structural Units ◽

Lytic Action ◽

Quartz Mercury

The incident energies required to kill Staphylococcus aureus or to inactivate its homologous bacteriophage have been measured at the various wave-lengths of the quartz mercury vapor arc between 238 and 302 mµ and found to run strictly parallel, the readings for the S. aureus phage being obtained at a uniformly higher energy level. This difference in levels is of less significance than the striking similarity in the shapes of the energy curves, which indicate that in both instances the same organic structures are absorbing the radiations. The results are open to three interpretations. The most obvious is that the bacteriophage is a submicroscopic organism. Again, it is possible that the bacteriophage is a product of its own lytic action on the homologous bacterium and contains the essential structural units which in S. aureus also are destroyed by ultraviolet light and thus cause the death of the organism. A third, more remote explanation is that the phage, of wholly unknown nature, is absorbed on S. aureus material in so intimate a bond that the alteration of this material by irradiation renders the phage incapable of further lytic activity.

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Carbon-Arc or Quartz Mercury-vapor Lights, The American Diet, and more

Scientific American ◽

10.1038/scientificamerican0230-158 ◽

1930 ◽

Vol 142 (2) ◽

pp. 158-159

Author(s):

Morris Fishbein

Keyword(s):

Mercury Vapor ◽

Quartz Mercury ◽

Carbon Arc

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Characterization of Cytokines and Proliferation Marker Ki67 in Chronic Rhinosinusitis with Nasal Polyps: A Pilot Study

Medicina ◽

10.3390/medicina57060607 ◽

2021 ◽

Vol 57 (6) ◽

pp. 607

Author(s):

Rudolfs Janis Viksne ◽

Gunta Sumeraga ◽

Mara Pilmane

Keyword(s):

Connective Tissue ◽

Chronic Rhinosinusitis ◽

Nasal Polyps ◽

Cellular Proliferation ◽

Rank Correlation ◽

Control Group ◽

Relative Distribution ◽

Proliferation Marker ◽

Ki 67 ◽

Stimulation Of

Background and Objectives: Chronic rhinosinusitis (CRS) is a condition that affects as much as 10.9% of the population and, along with presence of nasal polyps, is associated with significant morbidity and decreased quality of life. Studies on molecular pathways that have been activated in nasal polyp tissue are mainly based on cytokine concentration detection. Therefore, our aim is to investigate the complex appearance, relative distribution and interlinks of IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 and Ki 67 in chronic rhinosinusitis with nasal polyps (CRSwNP) affected human nasal mucosa. Materials and Methods: Samples of nasal polyps were obtained from 12 patients with previously diagnosed CRSwNP and no prior surgery. Control group consisted of samples from 17 otherwise healthy individuals with isolated nasal septum deviation. Tissues were stained for IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 and Ki67 immunohistochemically. Non-parametric statistic, Mann–Whitney U test and Spearman’s rank correlation coefficient were used. Results: All factors, except connective tissue cytokine IL-10 and proliferation marker Ki-67, had increased presence in connective tissue and decreased presence in epithelium of nasal polyps when compared to controls. Very strong and strong positive correlations between factors were observed. Conclusions: Decreased appearance of IL-1α, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 positive structures in the nasal epithelium with selective increase of IL-1α and IL-12 in nasal subepithelial connective tissue characterize the cytokine endotype with dysfunctional epithelial barrier and local stimulation of immune response in the connective tissue in case of chronic rhinosinusitis with polyps. Decrease of IL-6 in both—epithelium and connective tissue with strong correlation between it and IL-7 and IL-10 in connective tissue suggests significant stimulation of this regulatory cytokine and, possibly, the important role in pathogenesis of the development in nasal polyps. Correlations between Ki67 and cytokines indicate possible involvement of IL-4, IL-7 and IL-12 in regulation of cellular proliferation.

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A methodological reappraisal of non invasive high voltage electrical stimulation of lumbosacral nerve roots

Clinical Neurophysiology ◽

10.1016/j.clinph.2011.03.002 ◽

2011 ◽

Vol 122 (10) ◽

pp. 2071-2080 ◽

Cited By ~ 26

Author(s):

Walter Troni ◽

Alessia Di Sapio ◽

Eliana Berra ◽

Sergio Duca ◽

Aristide Merola ◽

...

Keyword(s):

Electrical Stimulation ◽

High Voltage ◽

Nerve Roots ◽

Non Invasive ◽

Stimulation Of

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Early Regenerative Modifications of Human Postmenopausal Atrophic Vaginal Mucosa Following Fractional CO2 Laser Treatment

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2018.058 ◽

2018 ◽

Vol 6 (1) ◽

pp. 6-14 ◽

Cited By ~ 14

Author(s):

Stefano Salvatore ◽

Katlein França ◽

Torello Lotti ◽

Marta Parma ◽

Sonia Palmieri ◽

...

Keyword(s):

Connective Tissue ◽

Laser Treatment ◽

Co2 Laser ◽

Vaginal Mucosa ◽

Structural Components ◽

Related Factors ◽

Fractional Co2 Laser ◽

Collagen Iii ◽

Co2 Laser Treatment ◽

Stimulation Of

BACKGROUND: Postmenopausal women experience undesired symptoms that adversely affect their quality of life. In the recent years, a specific 12 - week fractional CO2 laser treatment has been introduced, with highly significant relief of symptoms.AIM: The aim of this paper is the identification of the early modifications of structural components of atrophic vaginal mucosa induced by laser irradiation, which is responsible for the restorative processes.MATERIAL AND METHODS: We investigated by microscopical, ultrastructural and biochemical methods the modifications of the structural components of postmenopausal atrophic vaginal mucosa tissues after 1 hour following a single fractional laser CO2 application.RESULTS: In one hour, the mucosal epithelium thickens, with the maturation of epithelial cells and desquamation at the epithelial surface. In the connective tissue, new papillae indenting the epithelium with newly formed vessels penetrating them, new thin fibrils of collagen III are also formed in a renewed turnover of components due to the increase of metalloproteinase - 2. Specific features of fibroblasts support stimulation of their activity responsible of the renewal of the extracellular matrix, with an increase of mechanical support as connective tissue and stimulation of growth and maturation to epithelium thanks to new vessels and related factors delivered.CONCLUSION: We found the activation of regenerative mechanisms expressed both in the connective tissue - with the formation of new vessels, new papillae, and new collagen - and in the epithelium with the associated thickening and desquamation of cells at the mucosal surface.

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