Electroporation in dense cell suspension—Theoretical and experimental analysis of ion diffusion and cell permeabilization

Drops of cell suspension are seeded on nutrient medium containing 5% purified agar and spread between the agar surface and a cover glass. The liquid phase is absorbed by the concentrated agar, so that the cells are held in situ between glass and agar. After incubation nongerminated cells and micro-colonies are counted microscopically. Sporogenic capability is assessed by seeding very dense cell suspensions on acetate agar and covering with Teflon F.E.P. membrane which is permeable to oxygen.

Download Full-text

Theoretical and Experimental Analysis of Electroporated Membrane Conductance in Cell Suspension

IEEE Transactions on Biomedical Engineering ◽

10.1109/tbme.2010.2103074 ◽

2011 ◽

Vol 58 (12) ◽

pp. 3310-3318 ◽

Cited By ~ 16

Author(s):

D. O. H. Suzuki ◽

A. Ramos ◽

M. C. M. Ribeiro ◽

L. H. Cazarolli ◽

F. R. M. B. Silva ◽

...

Keyword(s):

Cell Suspension ◽

Experimental Analysis ◽

Membrane Conductance

Download Full-text

Electron microscopy of keratinocytes cultured on a collagen substrate used as an allograft for the treatment of chronic wounds

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130158 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1104-1105

Author(s):

Debby A. Jennings ◽

Michael J. Morykwas ◽

Louis C. Argenta

Keyword(s):

Electron Microscopy ◽

Cell Suspension ◽

Single Cell ◽

Chronic Wounds ◽

Mechanical Stability ◽

Uv Light ◽

Type I ◽

Single Cell Suspension ◽

Collagen Substrate ◽

Dermal Collagen

Grafts of cultured allogenic or autogenic keratlnocytes have proven to be an effective treatment of chronic wounds and burns. This study utilized a collagen substrate for keratinocyte and fibroblast attachment. The substrate provided mechanical stability and augmented graft manipulation onto the wound bed. Graft integrity was confirmed by light and transmission electron microscopy.Bovine Type I dermal collagen sheets (100 μm thick) were crosslinked with 254 nm UV light (13.5 Joules/cm2) to improve mechanical properties and reduce degradation. A single cell suspension of third passage neonatal foreskin fibroblasts were plated onto the collagen. Five days later, a single cell suspension of first passage neonatal foreskin keratinocytes were plated on the opposite side of the collagen. The grafts were cultured for one month.The grafts were fixed in phosphate buffered 4% formaldehyde/1% glutaraldehyde for 24 hours. Graft pieces were then washed in 0.13 M phosphate buffer, post-fixed in 1% osmium tetroxide, dehydrated, and embedded in Polybed 812.

Download Full-text

Three-dimensional distribution of ribulose-1, 5-bisphosphate carboxylase/oxygemase during the early development of proplastids in dark-grown Euglena cells transferred to an inorganic medium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162090 ◽

1990 ◽

Vol 48 (3) ◽

pp. 906-907

Author(s):

Tomoko Ehara ◽

Shuji Sumida ◽

Tetsuaki Osafune ◽

Eiji Hase

Keyword(s):

Cell Suspension ◽

Euglena Gracilis ◽

Carbon Materials ◽

Three Dimensional ◽

Peripheral Region ◽

Plastid Development ◽

Bisphosphate Carboxylase ◽

Inorganic Medium ◽

Ribulose 1 ◽

Dimensional Distribution

As shown previously, Euglena cells grown in Hutner’s medium in the dark without agitation accumulate wax as well as paramylum, and contain proplastids showing no internal structure except for a single prothylakoid existing close to the envelope. When the cells are transferred to an inorganic medium containing ammonium salt and the cell suspension is aerated in the dark, the wax was oxidatively metabolized, providing carbon materials and energy 23 for some dark processes of plastid development. Under these conditions, pyrenoid-like structures (called “pro-pyrenoids”) are formed at the sites adjacent to the prolamel larbodies (PLB) localized in the peripheral region of the proplastid. The single prothylakoid becomes paired with a newly formed prothylakoid, and a part of the paired prothylakoids is extended, with foldings, in to the “propyrenoid”. In this study, we observed a concentration of RuBisCO in the “propyrenoid” of Euglena gracilis strain Z using immunoelectron microscopy.

Download Full-text