Confocal Analysis of CNC based Hydrogels and Suspensions

2021 ◽  
Author(s):  
Aref Abbasi Moud ◽  
Amir Sanati Nezhad ◽  
Seyed Hossein Hejazi
Keyword(s):  
Laser Scanning ◽  
Healing Process ◽  
High Water ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
High Water Content ◽  
Self Healing ◽  
Signal Loss ◽  
Particle Mobility ◽  
Collapse Behavior

Abstract Cellulose nano crystal (CNC) hydrogels, while mechanically weak, have unique properties such as easy synthesis, high water content, and biocompatibility. Further improvement is needed to make CNC hydrogels mechanically stable and self-healable. Herein, using quantitative fluorescence recovery after photobleaching (FRAP) analysis, we assess stability, collapse, and level of self-healing of CNC hydrogels with different CNC and sodium chloride (NaCl) concentrations. We use the mean signal intensity obtained by confocal laser scanning microscopy (CLSM) to measure signal loss of the samples made of CNC hydrogels of different CNC concentrations and as a function of initial gel height and NaCl loading. The CNC dynamics inside the gels based on universality curves is unraveled which links the zeta potentials to the immobile particle percentages and the storage moduli as a function of NaCl/CNC concentration ratio. FRAP recovery analysis shows that for the ratio of NaCl/CNC beyond 0.1, the mobility of the ensemble of CNC particles becomes severely restricted. Hydrogel samples with low CNC concentrations (6 g/L and 10 g/L) experience a more substantial collapse rate under gravity than the rate observed for samples with a high CNC concentration (30 g/L). Increasing the CNC concentration hinders particle mobility and thus impedes the self-healing process. Quantification of the gel collapse behavior of CNC gel and its self-healing property is critical in many applications, including water and air filters, oil spill sponges, and tissue engineering.

scholarly journals Wound Healing Activity of Nanoclay/Spring Water Hydrogels

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 467 ◽  
Author(s):  
Fátima García-Villén ◽  
Angela Faccendini ◽  
Dalila Miele ◽  
Marco Ruggeri ◽  
Rita Sánchez-Espejo ◽  
...  
Keyword(s):  
Wound Healing ◽  
Laser Scanning ◽  
Healing Process ◽  
Spring Water ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Wound Healing Process ◽  
Accelerate Wound Healing ◽  
In Vitro Biocompatibility

Background: hydrogels prepared with natural inorganic excipients and spring waters are commonly used in medical hydrology. Design of these clay-based formulations continues to be a field scarcely addressed. Safety and wound healing properties of different fibrous nanoclay/spring water hydrogels were addressed. Methods: in vitro biocompatibility, by means of MTT assay, and wound healing properties were studied. Confocal Laser Scanning Microscopy was used to study the morphology of fibroblasts during the wound healing process. Results: all the ingredients demonstrated to be biocompatible towards fibroblasts. Particularly, the formulation of nanoclays as hydrogels improved biocompatibility with respect to powder samples at the same concentration. Spring waters and hydrogels were even able to promote in vitro fibroblasts motility and, therefore, accelerate wound healing with respect to the control. Conclusion: fibrous nanoclay/spring water hydrogels proved to be skin-biocompatible and to possess a high potential as wound healing formulations. Moreover, these results open new prospects for these ingredients to be used in new therapeutic or cosmetic formulations.

Restitution of single-cell defects in the mouse colon epithelium differs from that of cultured cells

2006 ◽  
Vol 290 (6) ◽  
pp. R1496-R1507 ◽  
Author(s):  
D. Günzel ◽  
P. Florian ◽  
J. F. Richter ◽  
H. Troeger ◽  
J. D. Schulzke ◽  
...  
Keyword(s):  
Single Cell ◽  
Laser Scanning ◽  
Pathogenic Bacteria ◽  
Cultured Cells ◽  
Healing Process ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Rapid Repair ◽  
E Coli ◽  
Tnf Α

Integrity of colon epithelium is of crucial importance and, as small defects occur constantly, rapid repair (restitution) is essential. To investigate the mechanism of restitution, single-cell lesions were induced in mouse colonic surface epithelia by iontophoretic injection of Ca2+. Closure of the resulting defects was monitored using confocal laser scanning microscopy (CLSM), and functional sealing by electrophysiological techniques. Restitution was evaluated as the time constant τ of the exponential decrease in conductance of an induced leak and amounted to 0.28 min under control conditions. After 4 min, the leak was completely sealed. Repair was thus considerably faster than in previously investigated HT-29/B6 cells (τ = 5.73 min). As in cultured cells, cytochalasin D delayed restitution in native colon epithelia (τ = 0.69 min), indicating the involvement of actin in the healing process; however, no accumulation of actin surrounding the lesion was detected. Long-term incubation of epithelia with IFN-γ alone or in combination with TNF-α increased τ to 0.49 and 0.59 min, respectively. In contrast to cultured cells, TNF-α alone did not affect restitution. A brief (<10 min) exposure to the sterile filtered supernatant of hemolytic E. coli O4 cultures did not affect the morphology of the epithelium, but delayed restitution. In CLSM studies, defects were still clearly visible 4 min after the onset of lesion induction. The supernatant of a nonhemolytic E. coli O4 mutant did not exhibit this effect. In conclusion, single-cell defects in native colon cause functional leaks that seal faster than in cell cultures. Proinflammatory cytokines and pathogenic bacteria delay restitution. This suggests a key role of very small lesions at the onset of pathogenic processes in the intestine.

3-D imaging of cells using a confocal laser scanning microscope and digital image processing

1988 ◽  
Vol 46 ◽  
pp. 96-97
Author(s):  
Thomas M. Jovin ◽  
Michel Robert-Nicoud ◽  
Donna J. Arndt-Jovin ◽  
Thorsten Schormann
Keyword(s):  
Laser Scanning ◽  
Confocal Laser Scanning Microscope ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Scanning Microscope ◽  
Laser Scanning Microscope ◽  
Biochemical Processes ◽  
Adjacent Structures

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.

Vacuoles Induced in Mammalian Cells by Helicobacter Cytotoxin are Acidic Organelles

1990 ◽  
Vol 48 (3) ◽  
pp. 168-169
Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich
Keyword(s):  
Acridine Orange ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ulcer Disease ◽  
Gastroduodenal Disease ◽  
H Pylori

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.

Use of confocal laser scanning microscopy and a computer model to understand ink cavitation and filamentation

TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA
Keyword(s):  
Laser Scanning ◽  
Confocal Laser Scanning Microscope ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Print Quality ◽  
Length Scale ◽  
Offset Printing ◽  
Significant Difference ◽  
Printing Speed

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.

ACTIVATED SLUDGE FLOC CHARACTERIZATION BY CONFOCAL LASER SCANNING MICROSCOPY

2012 ◽  
Vol 11 (3) ◽  
pp. 669-674 ◽  
Author(s):  
Szabolcs Szilveszter ◽  
Botond Raduly ◽  
Szilard Bucs ◽  
Beata Abraham ◽  
Szabolcs Lanyi ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser

Cuticular structures in the copulatory apparatus of Planorbis planorbis (Linnaeus, 1758) (Gastropoda: Pulmonata: Planorbidae)

2009 ◽  
Vol 18 (1) ◽  
pp. 11-16
Author(s):  
E.V. Soldatenko ◽  
A.A. Petrov
Keyword(s):  
Light Microscopy ◽  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Taxonomic Status ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Copulatory Apparatus ◽  
The Family ◽  
Cuticular Structures

The morphology of the copulatory apparatus and associated cuticular structures in Planorbis planorbis was studied by light microscopy, SEM, TEM and confocal laser scanning microscopy. The significance of these cuticular structures for the taxonomic status of the species and for the systematics of the family Planorbidae in general is discussed.

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