scholarly journals Structural Analysis of NaYF4 Solution Processed Nanoparticles for Hela Cell Studies

2020 ◽  
Vol 7 (1) ◽  
pp. 45-50
Author(s):  
Cliff Orori Mosiori ◽  
John. Maera

The NaYF4 nanoparticles were prepared and analyzed. Its structural analysis confirmed the formation of nanocrystals of desired sizes and spectral properties that can be incorporated into Hela cell studies. The internalization of NaYF4 nanoparticles in HeLa cells was determined at different nanoparticles concentrations and for incubation periods from 3 to 24 hours using various techniques. The images revealed a redistribution of nanoparticles inside the cell that increased with incubation time, concentration levels, and depended on the presence of the transfection factor. The study identified factors responsible for effective endocytosis of the NaYF4 nanoparticles to HeLa cells. Thus this procedure or method could be applied to investigate a wide range of future “smart” theranostic agents that may result in be very promising fluorescent probes for imaging real-time cellular dynamics.

2020 ◽  
Vol 7 (2) ◽  
pp. 87-92
Author(s):  
Cliff Orori Mosiori ◽  
John. Maera

The NaYF4 nanoparticles were prepared and analyzed. Its structural analysis confirmed the formation of nanocrystals of desired sizes and spectral properties that can be incorporated into Hela cell studies. The internalization of NaYF4 nanoparticles in HeLa cells was determined at different nanoparticles concentrations and for incubation periods from 3 to 24 hours using various techniques. The images revealed a redistribution of nanoparticles inside the cell that increased with incubation time, concentration levels, and depended on the presence of the transfection factor. The study identified factors responsible for effective endocytosis of the NaYF4 nanoparticles to HeLa cells. Thus this procedure or method could be applied to investigate a wide range of future “smart” theranostic agents that may result in be very promising fluorescent probes for imaging real-time cellular dynamics.


2014 ◽  
Vol 38 (12) ◽  
pp. 6152-6160 ◽  
Author(s):  
Vaibhavkumar N. Mehta ◽  
Sanjay Jha ◽  
Rakesh Kumar Singhal ◽  
Suresh Kumar Kailasa

Confocal laser microscopic images of HeLa cells using CDs as fluorescent probes.


2015 ◽  
Vol 1 (2) ◽  
pp. 116
Author(s):  
Dessy Arisanty ◽  
Zolkapli Eshak ◽  
Fauziah Othman ◽  
Asmah Rahmat ◽  
Abdah M.D. Akim ◽  
...  

 ABSTRACT Azadirachta indica A. Juss is a medicinal plant commonly known as neem. The effect of neem leaves extract on cervical cancer cells, however, has never been studied. Due to the lack of information, this study was conducted to determine the effect of neem leaves extract on cervical cancer (HeLa) cell growth. In vitro cytotoxicity effect of ethanolic neem extract indicated the presence of cytotoxicity activity of the extract against HeLa cells with IC50 of  30.0 μg/mL. The morphological changes under confocal laser scanning microscope (CLSM) on HeLa cells were cell shrinkage and membrane blebbing. There were also cells with condensed nucleus and few cells have fragmented nucleus, and finally formed apoptotic body. Control cells showed a clear cytoplasm and centrally placed nucleus and no cells exhibited any apoptotic features. Appearance of apoptotic cells under scanning electron microscope (SEM) are indentations, blebs and hole on cell surface and disintegration of cell. The controls remained morphologically normal. Apoptotic features of the cells are widely seen with longer incubation time while 24 hours incubation time, it is scarcely seen. The RT-PCR product showed that the c-erb gene expression was expressed in both treated and untreated HeLa cells. Contrary, the the c-myc and c-fos oncogenes on  HeLa cells which exposed to A. indica  EtOH extract were significantly decreased.  Thus, the results from this study strongly suggest that the ethanolic extract of A. indica may contain bioactive compound(s) that caused cervical cancer cells, HeLa cell death by apoptosis mechanism and lead to succession of discovering new alternative treatment for cervical cancer.  Keywords : cytotoxic, apoptosis genes, oncogenes, neem


Author(s):  
Svitlana Lobchenko ◽  
Tetiana Husar ◽  
Viktor Lobchenko

The results of studies of the viability of spermatozoa with different incubation time at different concentrations and using different diluents are highlighted in the article. (Un) concentrated spermatozoa were diluented: 1) with their native plasma; 2) medium 199; 3) a mixture of equal volumes of plasma and medium 199. The experiment was designed to generate experimental samples with spermatozoa concentrations prepared according to the method, namely: 0.2; 0.1; 0.05; 0.025 billion / ml. The sperm was evaluated after 2, 4, 6 and 8 hours. The perspective of such a study is significant and makes it possible to research various aspects of the subject in a wide range. In this regard, a series of experiments were conducted in this area. The data obtained are statistically processed and allow us to highlight the results that relate to each stage of the study. In particular, in this article it was found out some regularities between the viability of sperm, the type of diluent and the rate of rarefaction, as evidenced by the data presented in the tables. As a result of sperm incubation, the viability of spermatozoa remains at least the highest trend when sperm are diluted to a concentration of 0.1 billion / ml, regardless of the type of diluent used. To maintain the viability of sperm using this concentration of medium 199 is not better than its native plasma, and its mixture with an equal volume of plasma through any length of time incubation of such sperm. Most often it is at this concentration of sperm that their viability is characterized by the lowest coefficient of variation, regardless of the type of diluent used, which may indicate the greatest stability of the result under these conditions. The viability of spermatozoa with a concentration of 0.1 billion / ml is statistically significantly reduced only after 6 or even 8 hours of incubation. If the sperm are incubated for only 2 hours, regardless of the type of diluent used, the sperm concentrations tested do not affect the viability of the sperm. Key words: boar, spermatozoa, sperm plasma, concentration, incubation, medium 199, activity, viability, rarefaction.


2021 ◽  
Vol 2 (1) ◽  
pp. 63-81
Author(s):  
Sajana Manandhar ◽  
Erica Sjöholm ◽  
Johan Bobacka ◽  
Jessica M. Rosenholm ◽  
Kuldeep K. Bansal

Since the last decade, the polymer-drug conjugate (PDC) approach has emerged as one of the most promising drug-delivery technologies owing to several benefits like circumventing premature drug release, offering controlled and targeted drug delivery, improving the stability, safety, and kinetics of conjugated drugs, and so forth. In recent years, PDC technology has advanced with the objective to further enhance the treatment outcomes by integrating nanotechnology and multifunctional characteristics into these systems. One such development is the ability of PDCs to act as theranostic agents, permitting simultaneous diagnosis and treatment options. Theranostic nanocarriers offer the opportunity to track the distribution of PDCs within the body and help to localize the diseased site. This characteristic is of particular interest, especially among those therapeutic approaches where external stimuli are supposed to be applied for abrupt drug release at the target site for localized delivery to avoid systemic side effects (e.g., Visudyne®). Thus, with the help of this review article, we are presenting the most recent updates in the domain of PDCs as nanotheranostic agents. Different methodologies utilized to design PDCs along with imaging characteristics and their applicability in a wide range of diseases, have been summarized in this article.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Morteza Hasanzadeh Kafshgari ◽  
Delf Kah ◽  
Anca Mazare ◽  
Nhat Truong Nguyen ◽  
Monica Distaso ◽  
...  

Abstract Hollow titanium dioxide (TiO2) nanotubes offer substantially higher drug loading capacity and slower drug release kinetics compared to solid drug nanocarriers of comparable size. In this report, we load TiO2 nanotubes with iron oxide nanoparticles to facilitate site-specific magnetic guidance and drug delivery. We generate magnetic TiO2 nanotubes (TiO2NTs) by incorporating a ferrofluid containing Ø ≈ 10 nm iron oxide nanoparticles in planar sheets of weakly connected TiO2 nanotubes. After thermal annealing, the magnetic tubular arrays are loaded with therapeutic drugs and then sonicated to separate the nanotubes. We demonstrate that magnetic TiO2NTs are non-toxic for HeLa cells at therapeutic concentrations (≤200 µg/mL). Adhesion and endocytosis of magnetic nanotubes to a layer of HeLa cells are increased in the presence of a magnetic gradient field. As a proof-of-concept, we load the nanotubes with the topoisomerase inhibitor camptothecin and achieve a 90% killing efficiency. We also load the nanotubes with oligonucleotides for cell transfection and achieve 100% cellular uptake efficiency. Our results demonstrate the potential of magnetic TiO2NTs for a wide range of biomedical applications, including site-specific delivery of therapeutic drugs.


1988 ◽  
Vol 34 (3) ◽  
pp. 224-228 ◽  
Author(s):  
Aliza Kalo ◽  
Esther Segal

Findings from our previous studies revealed a correlation between the level of adherence in vitro of Candida albicans to human exfoliated vaginal epithelial cells (VEC) and the hormonal status of the cell donors. In the present study we investigated the effect of the sex hormones estradiol, estriol, progesterone, and testosterone on the binding of the yeasts to HeLa cell lines and VEC in vitro. Monolayers of HeLa cells were exposed to the hormones and yeasts under controlled conditions. The number of adherent yeasts per square millimetre of HeLa cell monolayers and the percentage of VEC with adherent yeasts was estimated by microscopic counts. The results showed that the tested sex hormones affected at various degrees the adhesion of yeasts to HeLa cells or VEC. Progesterone had the most marked effect, leading to a significant increase in the number of adherent yeasts to HeLa cells or in the percentage of adhesion of VEC. In addition, VEC were separated on Percoll gradients into the two cell types: superficial (S) and intermediate (I), cell types which appear physiologically under increased serum levels of estradiol or progesterone, respectively. Adhesion assays with the separated cell populations revealed an increased binding capacity of the I cells. The finding that progesterone increased the adherence of yeasts to genital mucosa and that VEC of the I type have a higher capacity to adhere the yeasts is compatible with our previous observation that increased numbers of I cells, appearing under high level of progesterone, are found in situations known to have predisposition to vaginal candidiasis. Thus, our data point to a possible involvement of the hormone progesterone in the adherence of C. albicans to genital epithelium.


RSC Advances ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. 5282-5296 ◽  
Author(s):  
Marija S. Jeremić ◽  
Hubert Wadepohl ◽  
Vesna V. Kojić ◽  
Dimitar S. Jakimov ◽  
Ratomir Jelić ◽  
...  

Two new Rh(iii)–ed3a complexes [Rh(ed3a)(OH2)]·H2O and Na[Rh(ed3a)Cl]·H2O have shown good antitumor activity, especially against HeLa cell line.


1994 ◽  
Vol 107 (2) ◽  
pp. 425-434 ◽  
Author(s):  
A.B. Hassan ◽  
R.J. Errington ◽  
N.S. White ◽  
D.A. Jackson ◽  
P.R. Cook

HeLa cells synchronized at different stages of the cell cycle were permeabilized and incubated with analogues of nucleotide triphosphates; then sites of incorporation were immunolabeled with the appropriate fluorescent probes. Confocal microscopy showed that sites of replication and transcription were not diffusely spread throughout nuclei, reflecting the distribution of euchromatin; rather, they were concentrated in ‘foci’ where many polymerases act together. Transcription foci aggregated as cells progressed towards the G1/S boundary; later they dispersed and became more diffuse. Replication was initiated only at transcription sites; later, when heterochromatin was replicated in enlarged foci, these remained sites of transcription. This illustrates the dynamic nature of nuclear architecture and suggests that transcription may be required for the initiation of DNA synthesis.


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