scholarly journals The effect of injection speed and serial injection on propidium iodide entry into cultured HeLa and primary neonatal fibroblast cells using lance array nanoinjection

SpringerPlus ◽  
2016 ◽  
Vol 5 (1) ◽  
Author(s):  
John W. Sessions ◽  
Tyler E. Lewis ◽  
Craig S. Skousen ◽  
Sandra Hope ◽  
Brian D. Jensen
Author(s):  
John W. Sessions ◽  
Brad W. Hanks ◽  
Dallin L. Lindstrom ◽  
Sandra Hope ◽  
Brian D. Jensen

Understanding environmental factors relative to transfection protocols is key for improving genetic engineering outcomes. In the following work, the effects of temperature on a nonviral transfection procedure previously described as lance array nanoinjection are examined in context of molecular delivery of propidium iodide (PI), a cell membrane impermeable nucleic acid dye, to HeLa 229 cells. For treatment samples, variables include varying the temperature of the injection solution (3C and 23C) and the magnitude of the pulsed voltage used during lance insertion into the cells (+5 V and +7 V). Results indicate that PI is delivered at levels significantly higher for samples injected at 3C as opposed to 23C at four different postinjection intervals (t = 0, 3, 6, 9 mins; p-value ≤ 0.005), reaching a maximum value of 8.3 times the positive control for 3 C/7 V pulsed samples. Suggested in this work is that between 3 and 6 mins postinjection, a large number of induced pores from the injection event close. While residual levels of PI still continue to enter the treatment samples after 6 mins, it occurs at decreased levels, suggesting from a physiological perspective that many lance array nanoinjection (LAN) induced pores have closed, some are still present.


Reproduction ◽  
2000 ◽  
pp. 145-152 ◽  
Author(s):  
B Pintado ◽  
J de la Fuente ◽  
ER Roldan

This study was designed to assess whether nucleic acid stains such as propidium iodide and Hoechst 33258 and the cytosolic stain eosin identified equivalent proportions of non-viable cells. Sub-samples of boar spermatozoa stored for up to 72 h, and frozen bull spermatozoa stored in straws and thawed before staining, were exposed to either propidium iodide or Hoechst 33258 alone or in combination. Additional sub-samples were stained with eosin-nigrosin and subsequently with Giemsa. The proportion of non-viable cells identified by propidium iodide alone was equivalent to that observed when it was used in combination with the other fluorescent probe. Similar results were observed for Hoechst 33258. However, direct microscopic examination of sub-samples exposed to both stains revealed that a proportion of spermatozoa stained with propidium iodide did not incorporate Hoechst 33258. This was found consistently in boar and bull spermatozoa under the different experimental conditions used. Quantification showed that the proportion of propidium iodide-positive cells was significantly higher than Hoechst 33258-positive cells. Furthermore, the proportion of propidium iodide-positive cells was higher than cells stained with eosin, but no differences were found between the number of cells stained with Hoechst 33258 or eosin. The proportion of cells stained with propidium iodide was positively correlated with the proportion stained with either Hoechst 33258 or eosin, despite the observation that more cells incorporated propidium iodide. Taken together, these results indicate that there are differences in the ability of fluorescent probes to identify non-viable sperm cells and that this should be considered when staining protocols are used to analyse sperm viability, or when viability is used as a discriminating factor in functional studies, such as those related to acrosomal exocytosis.


2017 ◽  
pp. 62-67
Author(s):  
V. G. Kuznetsov ◽  
O. A. Makarov

At cementing of casing of oil and gas wells during the process of injecting of cement slurry in the casing column the slurry can move with a higher speed than it’s linear injection speed. A break of continuity of fluid flow occurs, what can lead to poor quality isolation of producing formations and shorten the effective life of the well. We need to find some technical solution to stabilize the linear velocity of the cement slurry in the column. This task can be resolved with an automated control system.


2013 ◽  
Vol 21 (2) ◽  
pp. 115-123 ◽  
Author(s):  
Nathan Unsworth ◽  
Raymond Dawson ◽  
John Wade ◽  
Chun-Qiang Liu

2019 ◽  
Vol 15 ◽  
Author(s):  
Thais Batista Fernandes ◽  
Natanael Dante Segretti ◽  
Felipe Rebello Lourenço ◽  
Thalita Marcílio Cândido ◽  
André Rolim Baby ◽  
...  

Background: Antimicrobial resistance is a persistent problem about infections treatment and carries needing for develop new antimicrobial agents. Inhibiting of bacterial β-ketoacyl acyl carrier protein synthase III (FabH), which catalyzes the condensation reaction between a CoA-attached acetyl group and an ACP-attached malonyl group in bacteria is an interesting strategy to find new antibacterial agents. Objective: The aim of this work was to design and synthesize arylsulfonylhydrazones potentially FabH inhibitors and evaluate their antimicrobial activity. Methods: MIC50 of sulfonylhydrazones against E. coli and S. aureus was determined. Antioxidant activity was evaluated by DPPH (1-1’-diphenyl-2-picrylhydrazyl) assay and cytotoxicity against LL24 lung fibroblast cells was verified by MTT method. Principal component analysis (PCA) was performed in order to suggest a structure-activity relationship. Molecular docking allowed to propose sulfonylhydrazones interactions with FabH. Results: The most active compound showed activity against S. aureus and E. coli, with MIC50 = 0.21 and 0.44 µM, respectively. PCA studies correlated better activity to lipophilicity and molecular docking indicated that sulfonylhydrazone moiety is important to hydrogen-bond with FabH while methylcatechol ring performs π-π stacking interaction. The DPPH assay revealed that some sulfonylhydrazones derived from the methylcatechol series had antioxidant activity. None of the evaluated compounds was cytotoxic to human lung fibroblast cells, suggesting that the compounds might be considered safe at the tested concentration. Conclusion: Arylsufonylhydrazones is a promising scaffold to be explored for design of new antimicrobial agents.


Author(s):  
Zeinab Abedian ◽  
Niloofar Jenabian ◽  
Ali Akbar Moghadamnia ◽  
Ebrahim Zabihi ◽  
Roghayeh Pourbagher ◽  
...  

Objective/ Background: Cancer is still the most common cause of morbidity in world and new powerful anticancer agents without severe side effects from natural sources is important. Methods: The evaluation of cytotoxicity and apoptosis induction was carried out in MCF-7,HeLa and Saos-2 as cancerous cell lines with different histological origin and human fibroblast served as control normal cell. The cells were treated with different concentrations of chitosan and the cytotoxicity was determined using MTT assay after 24, 48 and 72 h .The mode of death was evaluated by flow cytometry . Results: While both types of chitosan showed significant concentration-dependently cytotoxic effects against the three cancerous cell lines, fibroblast cells showed somehow more compatibility with chitosan. On the other hand, there were no significant differences between LMWC and HMWC cytotoxicity in all cell lines. The flow cytometry results showed the apoptosis pattern of death more in Saos-2 and HeLa while necrosis was more observable with MCF7. Also higher viability with both types of chitosan was seen in fibroblast as normal cells Conclusion: Chitosan shows anticancerous effect against 3 cancerous cell lines, while it is compatible with normal diploid fibroblast cells. Furthermore, it seems that the molecular weight of chitosan does not affect its anticancerous property.


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