Higher Percentage Of Viable Cells Research Articles

Comparative Evaluation of Surgical Techniques for Pterygium Management: An In Vitro Study

ABSTRACT Background: Pterygium is a common ocular surface disorder characterized by the growth of fibrovascular tissue onto the cornea, leading to discomfort and visual impairment. Various surgical techniques, including conjunctival autografting, amniotic membrane transplantation, and bare sclera excision, are employed in the management of pterygium. Materials and Methods: Cultured human conjunctival epithelial cells were subjected to simulated pterygium conditions, mimicking the fibrovascular proliferation observed in vivo. Subsequently, different surgical techniques, including conjunctival autografting, amniotic membrane transplantation, and bare sclera excision, were simulated in vitro. Cell viability, proliferation, migration, and inflammatory cytokine expression were assessed using various assays, including MTT assay, scratch assay, and enzyme-linked immunosorbent assay (ELISA). Untreated cells served as controls for comparison. Results: Conjunctival autografting demonstrated superior outcomes in terms of cell viability and proliferation compared to amniotic membrane transplantation and bare sclera excision. Autografted cells exhibited a significantly higher percentage of viable cells and enhanced proliferative capacity compared to cells subjected to other surgical techniques (P < 0.05). Additionally, conjunctival autografting promoted faster cell migration into the defect area, resulting in more rapid wound closure compared to other techniques. Furthermore, reduced expression of inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), was observed in cells treated with conjunctival autografts compared to other groups. Conclusion: In vitro findings suggest that conjunctival autografting may offer superior outcomes in the management of pterygium compared to amniotic membrane transplantation and bare sclera excision.

A 3-step method for preparing cryopreserved samples of apheresis products for post-thaw analysis yields a higher percentage of viable cells.

Standard flow cytometry protocols for CD34+ cell enumeration designed for fresh samples are not appropriate for cryopreserved products. Special protocols have been developed to remove the cryoprotectant by quickly washing a freshly thawed sample. Exposing cells to a large volume of hypotonic solution and subsequent washing process was hypothesized to cause lab-induced cell death. Moreover, standard gating strategies must be altered to avoid reporting falsely high viabilities. We developed a novel method whereby thawed samples were diluted step-wise to 1:2 by 3 additions of 1/3 sample volume using 1% Human Albumin in Dextran 40 (10% Low Molecular Weight Dextran in 0.9% NaCl) separated by 5 min between each addition. An additional 1:10 dilution was required to obtain a desired cell concentration for flow cytometry testing resulting in a 1:20 dilution. Twenty samples were tested simultaneously in a method comparison; the new method demonstrated significant increases in mean cell viabilities for white blood cells, hematopoietic progenitor cells, and T cells as well as reduced standard deviations for each parameter. Slow, step-wise dilutions of freshly thawed samples of cryopreserved apheresis products to 1:20 yielded higher and more precise viability measurements compared to quickly washing samples to remove DMSO.

A pilot study: Changes of MDAMB-231 cancer cell line response to synthesized oleic acid – coated MgFe2O4 nano ferrite compound and its cytotoxic effects on L929 cell line

In this investigation, we synthesized MgFe2O4 nano ferrite compounds using the sol-gel method and coated them with oleic acid. The synthesized compounds were evaluated for cytotoxicity study on the L929 cell line and the anticancer activity against the breastcancer-MDAMB-231 cellline using in vitro approach. The physical structure of the compounds was confirmed to have a cubic spinel structure and Fd3m space group using X-ray diffraction (XRD). Scherrer's formula revealed crystallite sizes of 11 nm for MgFe2O4and 33 nm for oleic acid-coated MgFe2O4 nanoferrites. Fourier transform infrared (FTIR) spectroscopy confirmed the existence of MgFe2O4 inuncoated and coated compounds. Scanning electron microscopy (SEM) was used to examine the surface structure and morphology of the synthesized compounds. The compounds show a grain-like structure with a little agglomeration. With the help of histogram graph average size of the particles are determined, where the MgFe2O4 and coated MgFe2O4 have 17.2 and 20 nm average particle sizes. Testing of magnetic properties was done with a vibrating sample magnetometer (VSM), demonstrating ferromagnetic properties for the samples. Cytotoxicity tests revealed that MgFe2O4 exhibited higher cytotoxicity compared to oleic acid-coated MgFe2O4 nanoferrite on L929 cells. MgFe2O4 & oleic acid-coated MgFe2O4 compounds were tested on the MDAMB-231 breast cancer cell line, with the uncoated sample displaying significantly greater anticancer activity, as evidenced by a higher percentage of cell viability and a lower IC50 value of 55.67 µg compared to 65.97 µg for the coated sample.

Polycaprolactone/cress seed mucilage based bilayer antibacterial films containing ZnO nanoparticles with superabsorbent property for the treatment of exuding wounds

In this research, a novel double-layer film based on polycaprolactone and cress seed mucilage containing zinc oxide nanoparticles (0.5–2 %) was synthesized using solution casting technique, as an interactive multi-functional wound dressing. The bilayer films were characterized by measuring moisture content, contact angle parameter, porosity, water vapor transmission rate (WVTR), color attributes and opacity, swelling, degradation, mechanical properties, cell viability, and antimicrobial activity, as well as using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results indicated that the film containing 1.5 % zinc oxide nanoparticles had the best performance, with high swelling ability (3600 %) and 25 % degradation within 24 h of placement in a wound simulator solution. Its mechanical properties, including tensile strength and elongation at break, were 9 MPa and 5.53 %, respectively. In investigating the antimicrobial activity of the optimal film against Escherichia coli and Staphylococcus aureus, the diameter of the inhibition zone was observed to be 39.33 and 42 mm, respectively. Moreover, increasing the number of ZnO-NPs hindered the growth of NIH/3T3 cells, but the 1.5 % ZnO-NP loaded film showed a high percentage of cell viability in 1 day (90 %) and 3 days (93 %), which is suitable for biomedical applications.

Low-Intensity Electrical Stimulation Improved the Mineralization of Adipose-Derived Mesenchymal Stem Cells

Multipotent mesenchymal stromal cells (MSCs) derived from adipose tissue have been increasingly studied due their lessinvasive extraction surgery, self-renew and differentiation potential. The literature has not been reported the comparison of different sources of MSCs derived from distinct adipose tissues and the use of electrical stimulation (ES) for tooth and bone tissue regeneration. The present study evaluated in vitro cell viability by MTT, cell proliferation by CCK-8 and the osteogenic differentiation by alizarin red-S staining of MSCs from Wistar rats adipose tissue, abdominal (ABD) and inguinal (ING), submitted to ES therapy. ES was applied during 60s, 150s and 300s at 10µA-intensity 3x/week. The ES therapy was not cytotoxic at any time of the experimentation. MSCs from ING presented higher percentage of cell viability at 60s of ES than MSCs from ABD stimulated for 150s and 300s. Moreover, MSCs from ING presented higher proliferation rate than ABD at all three ES time-application. The use of ES therapy during the osteogenic differentiation contributed positively to improve the mineralization process. MSCs from ING presented 30% greater mineralization at 150s, and 50% at 300s, while ABD showed 50% greater at 60s of ES. In conclusion, MSCs from ING and ABD are able to increase cell proliferation and improve osteogenic mineralization, but with different responses depending on the ES stimuli at the same experimental condition, which reinforce the needing for further investigation on the use of MSCs derived from fat tissue and ES to optimize their use for cell proliferation and mineralization in regenerative medicine.

Comparison of THP-1 Macrophages Viability in Different Types of Culture Vessel

The ox-LDL generated apoptotic bodies using THP-1 macrophage is a useful tool to study foam cell formation in atherosclerosis. However, the common problem is the cells in the negative control (i.e., absence of ox-LDL) undergo apoptosis. Therefore, the type of cell culture vessel was proposed to be the key factor contributing to cell apoptosis. The THP-1 cells were differentiated into M1 macrophages using 10 ng/μL PMA, 5 ng/μL LPS, and 20 ng/μL IFN-? while 5 ng/μL PMA, 20 ng/μL IL-4 and 20 ng/μL IL-13 were used to differentiate THP-1 into M2 macrophages. Two types of cell culture vessels (6-well plate and T25 flask) were used to culture the macrophages. The cells were subsequently stained using Annexin V-FITC and Propidium Iodide prior to flow cytometry analysis. Interestingly, both M1 and M2 macrophages cultured in the T25 flask resulted in a significantly higher percentage of cell viability compared to macrophages cultured in 6-well plate [M1: 84.15% ± 4.39 vs 8.02% ± 1.55, p < 0.0001; M2: 95.95% ± 1.74 vs 10.50% ± 0.05, p < 0.0001]. In summary, the type of culture vessel is a vital factor in determining cell viability attributed to the surface area and cell seeding density in different types of vessels.

Effect of Different Sealers on the Cytocompatibility and Osteogenic Potential of Human Periodontal Ligament Stem Cells: An In Vitro Study.

There is tendency for unavoidable sealer extrusion in some clinical cases. This might adversely affect host stem cells and affect healing. This study aimed to investigate the effect of different sealers on the cytocompatibility and osteogenic potential of human periodontal ligament stem cells (hPDLSCs). The cytotoxic effect of the extracted elutes of VDW.1Seal (VDW.1), Endosequence BC Sealer HiFlow (ES), GuttaFlow-2 (GF), and ADSeal (AD-S) on the hPDLSCs was determined using the MTT assay. Cell proliferation and migration were assessed by the scratch wound healing assay. Osteogenic differentiation potential was assessed. Measurement of pH values and calcium ions release was performed. GF had a significantly higher percentage of viable cells. The cell migration assay showed that GF demonstrated the lowest open wound area percentage. GF and AD-S showed the highest calcium nodule deposition. GF demonstrated higher ALP activity than ES. Expression of RUNX2 and OC genes was similar for all sealers, while OPG gene expression was significantly higher for VDW.1 and GF. ES and AD-S displayed the highest pH values on day 1. Calcium ion release of ES and VDW.1 was significantly the highest. GuttaFlow-2 and VDW.1Seal sealers have favorable behavior toward host stem cells.

Success of replantation of avulsed teeth using human colostrum as an interim storage medium

ObjectivesTooth avulsion is defined as total tooth displacement from the alveolar socket; the best treatment is replantation of the tooth. Human milk influences body health, growth, and development related to the presence of micro and macro nutrient components. This study assessed the effects of human colostrum as a storage medium on the success of tooth replantation. MethodsThe upper left incisor of 30 adult male Wistar rats was extracted, and the rats were divided into three groups according to the storage medium of the extracted tooth for replantation: Hank's balanced salt solution (HBSS), tap water, and colostrum groups. The MTT cell viability assay was conducted, and histological evaluation and histomorphometric analyses were performed on postoperative day 45 for identification of pulp necrosis, periodontal hyalinization, percentage of resorbed area, and the periodontal ligament attachment. ResultsThe colostrum medium showed a higher percentage of cell viability followed by HBSS with statistical significance. Histological findings of the replanted avulsed tooth that soaked in tap water as storage medium showed obvious external and internal root resorption. Pulp necrosis and periodontal ligament hyalinization and with a significant differences values in comparison to HBSS and colostrum groups (p > 0.05), whereas the colostrum group showed new well-reattached periodontal ligament with normal pulp and no evidence of root resorption. ConclusionTooth loss is minimized by using human colostrum as storage medium in replantation of an avulsed tooth after a 1 h period compared to HBSS and water.

Ammonium chloride and urea based deep eutectic solvent: toxicological and antioxidant profile Authors

In the present study, the toxicity potential of ammonium chloride and urea-based deep eutectic solvent (DES) was studied. A homogeneous DES solution was obtained by heating at 60°C for 20 minutes. Fourier Transform Infrared Spectroscopy (FTIR) analysis was used to verify the synthesis. The toxicity profiling of ammonium-based DES was performed using in vitro cell lines (fibroblast growth factor) and microbes (fungi, Gram positive and gram negative bacteria) and in vivo model organism (fish). DES was found to the had maximum zone of inhibition against tested bacterial (Staphylococcus aureus) and fungal strains (Candida albicans). Ammonium chloride-urea DES had higher LC50 against Cyprinus carpio. DES was found to have a higher percentage of cell viability at higher concentration along with DPPH scavenging activity of 92%. In conclusion, ammonium chloride-urea based DES had been successfully formed and found less harmful at higher concentrations, thus can be used as promising solvents in the future.

Polyethylene glycol modified-carbon nanotubes as materials for biomedical applications: In vitro and in vivo sub-acute toxicity evaluation

• MWCNTs modification minimizes their toxicity while improving their performance. • Functionalized MWCNTs displays high percentage of cells viability on human skin fibroblast cells. • Functionalized MWCNTs induces none to minimum sub-acute toxicity in rats. Multiwalled-carbon nanotubes (MWCNTs) serve as one of the popular options for biomedical applications. Nonetheless, MWCNTs toxicity and biosafety are concerned, particularly on their aggregation after systemic distribution, necessitating modification. Although there was evidence of the toxicity of MWCNTs in the literature, the inconsistent parameters reported by each study, however, provide limited information to claim the sub-acute toxicity caused by MWCNTs. Thus, the present study aims to evaluate the subacute toxicity of modified MWCNTs, both in vitro and in vivo. In this study, polyethylene glycol-MWCNTs (PEG-MWCNTs) were characterized by standard characterization analysis. Exposure of PEG-MWCNTs on normal human fibroblast cells in vitro exhibited a high percentage of cell viability while in vivo assessment demonstrated no significant changes in rats’ behavior, body weight and serum biochemical analysis. Moreover, organ histological analysis indicated no significant changes following PEG-MWCNTs administration. No-observed-adverse-effect-level (NOAEL) value from this study was determined at 4 mg/kg. Results from this study suggested that modified MWCNTs induced minimal toxicity effect following systemic delivery in rats, thus, could be an excellent material for biomedical applications.

Structural, morphological, optical, photocatalytic activity and bacterial growth inhibition of Nd-doped TiO2 nanoparticles

In this work, we synthesized the undoped and neodymium-doped TiO2 nanoparticles (Nd@TiO2) with various dopant concentrations using the facile sol–gel method. The PXRD results have shown that the synthesized NPs are tetragonal crystal structures, exhibiting an anatase phase. The direct bandgap values of undoped and Nd@TiO2 NPs vary from 3.19 eV to 3.30 eV, as determined from the Tauc plot. Additionally, HR-SEM and TEM have examined surface morphology, particle size, and microstructures of as-synthesized Nd@TiO2 NPs. Moreover, a sample of 5 mol.% Nd@TiO2 has shown enhanced photocatalytic activity than that of bare TiO2 NPs with the reactive black-5 (RB5) under UV light. Further, the synthesized undoped and Nd@TiO2 NPs have been incorporated with the bacteria of E. coli and B. subtilis through flow cytometry, where the 5 mol.% Nd@TiO2 NP has shown a high percentage of cell viability.

Industrialization of an Academic Miltenyi Prodigy-Based CAR T Process

INTRODUCTIONWe have previously described AUTO1, a CD19 CAR with a fast off-rate binding domain, designed to reduce CAR T-cell immune toxicity and improve engraftment. Clinical testing in two academic studies in relapsed/refractory (r/r) paediatric [NCT02443831; CARPALL] and adult B-ALL, B-NHL and B-CLL [NCT02935257; ALLCAR19] confirmed the intended function of the receptor, with low levels of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) and long-term engraftment of CAR T-cell 1,2. Based on data in adult B-ALL, we initiated a phase Ib/II registration study in r/r adult B-ALL [NCT04404660; FELIX]. To facilitate this study and future commercialization, industrialization of the manufacturing process was required.METHODS & RESULTSThe original process in the academic studies was based on the Miltenyi CliniMACS Prodigy T cell transduction process. Leukapheresis was performed at the same site as manufacture. T cells were isolated from pheresis by CD4/CD8 positive selection and seeded onto the Prodigy to be activated using the Miltenyi CD3/CD28 targeting activating reagent, TransAct. The following day, transduction was carried out using a lentiviral vector. Cells were cryopreserved after an expansion phase of up to day 10 of the process.To facilitate industrialization of the AUTO1 manufacture in the multi-center, multi-regional FELIX study, we first explored the use of cryopreserved pheresis (81.3% median viability pre-selection (range 71.9 - 94.3), 1.0 days median doubling time (range 0.9 - 1.5) and 47.6% median CD19 CAR expression (range 19.1-62.1)). We concluded that optimal manufacture includes the use of fresh pheresis and the initiation of manufacture within 72 hours (99.0% median viability pre-selection (range 92.5 - 99.7), 1.3 days median doubling time (range 1.1 - 2.1) and 69.3% median CD19 CAR expression (range 22.9-86.2)).To further simplify the process, we explored removal of the pre-selection step. Full-scale runs using starting material from 4 healthy donors were conducted to compare CD4/CD8 selected with unselected cells. On the day following activation, selected cells displayed a higher percentage of viable cells, defined as cPARP-FVS780- (median: 76.1%, range: 84.5-66.4) as compared to unselected cells (median: 52.2%, range: 43.6-59.0). In addition, selected cells demonstrated a median of 23-fold expansion (range: 20.0 - 29.1) compared to a 13.3-fold expansion for unselected cells (range 6.1-17.4). Median transduction efficiencies of viable CAR+ T-cells were 53.9% (range: 43.2-56.9) and 78.0% (range: 64.5-81.1) in selected and unselected cells, respectively. CD4/8 pre-selection was determined to be a critical part of the process.A comparison of phenotype between 18 batches manufactured using the academic process and 5 batches produced from fresh material using the industrial process was carried out. No significant differences, as determined by 2-way ANOVA, were observed between the percentage of CAR+ CD3+ cells, the memory phenotype (% TSC/naive, % TCM, % TEM and % TEMRA) and the percentage expression of PD1 (figure 1). The CD4/CD8 ratio was also comparable between products of the two processes.Data from the initial 6 fresh in patients show that engraftment in the FELIX study is consistent with ALLCAR19 engraftment results. Additional patients, updated clinical data and longer follow-up will be presented at the conference.CONCLUSIONIndustrialization of an autologous Miltenyi CAR T process is feasible, leading to a comparable product to that manufactured in an academic setting. We have now opened the pivotal multi-center phase II part of the FELIX study in r/r adult B-ALL patients.REFERENCES 1.Ghorashian S et al. (2019) Enhanced CAR T cell expansion and prolonged persistence in pediatric patients with ALL treated with a low-affinity CD19 CAR. Nat Med, 25(9):1408-1414.2.Roddie C et al. (2021) Durable responses and low toxicity after fast off-rate CD19 CAR-T therapy in adults with relapsed/ refractory B-ALL. J Clin Oncol, in pressFigure 1. Comparison of phenotype between 18 CAR T cell batches manufactured using the academic process and 5 batches produced using the industrial process. Boxes represent median, 25th and 75th percentiles and whiskers represent minimum and maximum. [Display omitted] DisclosuresCulshaw: Autolus Ltd.: Current Employment. Arce Vargas: Autolus Ltd.: Current Employment. Santiago Toledo: Autolus Ltd.: Current Employment. Roddie: Novartis: Consultancy; Celgene: Consultancy, Speakers Bureau; Gilead: Consultancy, Speakers Bureau. Shaughnessy: BMS: Honoraria, Speakers Bureau; Sanofi: Honoraria, Speakers Bureau; Kite: Honoraria, Speakers Bureau. Cerec: Autolus Ltd.: Current Employment. Duffy: Autolus Ltd.: Current Employment. Perna: Autolus Ltd.: Current Employment. Brugger: Autolus Ltd.: Current Employment. Merges: Autolus Ltd.: Current Employment. Pule: Autolus Ltd: Current Employment.

LIN28B Enhanced STAT3 Signaling Regulates Inflammatory Response and Chemotherapeutic Resistance in Cholangiocytes.

Background:LIN28B is functionally driving malignant transformation and relevance to the worse disease outcomes by promoting cancer aggressiveness. However, a typical role of LIN28B in cholangiocarcinoma (CCA) is primarily unknown. In this study, the tumorigenic potential of LIN28B in the cholangiocyte context was investigated. Methods: Stable LIN28B expression in MMNK-1 cells was generated by infecting with retrovirus-containing LIN28B gene. LIN28B-overexpressing cells were further validated the amount of released cytokines by using human cytokine arrays. After treatment of chemo-drugs, cell viability was subsequently measured using MTT assay. Aldehyde dehydrogenase (ALDH) activity was determined using ALDEFLUOR assay Kit and analyzed by flow cytometry. The mRNA and protein expression levels were respectively assayed by RT-qPCR and western blot. Results:Cytokine release results showed that numerous inflammatory cytokines-chemokines related to cancer initiation and development, such as IL-8, IL-6, VEGF, MCP1, TNF-α were significantly increased in LIN28B-overexpressing MMNK-1 cells. Drug sensitivity test showed that LIN28B-overexpressing MMNK-1 treated cells had a high percentage of cell viability compared to MMNK-1-control treated cells. Activity and expression level of a cancer stem cell marker, ALDH was significantly elevated in LIN28B-overexpressing MMNK-1 cells. Moreover, the activation of an oncogenic signaling pathway, signal transducer and activator of transcription 3 (STAT3) was enhanced in LIN28B-overexpressing MMNK-1 cells. Whereas, growth capacity of LIN28B-overexpressing MMNK-1 cells was found to be reduced in STAT3 inhibition. Conclusion:LIN28B can regulate the inflammatory response and resistance to chemotherapy of cholangiocytes through modulation of STAT3 signaling pathway.A recent study suggests that activated cholangiocytes can be induced by regulation of LIN28B/STAT3 pathway and this may partially contribute to the initiating CCA. Here, LIN28B and its downstream signaling could be considered as an attractive therapeutic target in patients with CCA.

Cytotoxic Evaluation of Mala aluation of Malaysian K ysian Kelulut Hone elulut Honey on Human y on Human Gingival Fibr al Fibroblast Cell Line using M oblast Cell Line using MTT Assay

Kelulut honey or stingless bee honey is a type of honey produced by stingless bees of the Trigona species where the nest is found in living trees. Objective: The aim of this study was to evaluate the cytotoxic potential of Malaysian Kelulut honey by employing MTT assay on a human gingival fibroblast cell line. Methods: Human gingival fibroblast cell line was cultured in minimal essential medium alpha (α-MEM) with 10% foetal bovine serum and 1% penicillin-streptomycin solution in a 5% CO2 incubator at 37°C in a humidified atmosphere. The cells were seeded at a cell density of 5x103 cells/well in a 96-well culture plate for 24 hours. The cells were treated with seven different concentrations (200, 100, 50, 25, 12.5, 6.25, and 3.125mg/ml) of Malaysian Kelulut honey and incubated in a CO2 incubator. The negative control comprised cells treated with growth media alone. The cell viability was assessed using MTT assay at 24, 48, and 72 hours. The test plate was shaken using a microplate shaker and the absorbance of the solution was measured at 570nm using an ELISA reader with the Magellan software. Statistical analysis of the data was carried out using Kruskal-Wallis test and SPSS 24.0.0 for Windows. A p value <0.05 was considered as statistically significant. Results: There was no cytotoxic effect of Malaysian Kelulut honey on HGF-1 based on the MTT assay at different concentrations and at different time points tested as the cell viability was above 70%. The highest percentage of cell viability at all three different durations of treatment were observed at 3.125mg/ml, whereas the lowest cell viability was observed at 200mg/ml of Kelulut honey concentration. However, statistically significant differences were seen between some of the concentrations at various time points. Conclusion: Since the cell viability of HGF-1 treated with Malaysian Kelulut honey was more than 70% at all concentrations ranging from 3.125mg/ml to 200mg/ml at three different time points (24, 48 and 72 hours), Malaysian Kelulut honey can be considered as non-cytotoxic on human gingival fibroblasts based on MTT assay under the present test conditions

Surface Bioactivation of Polyether Ether Ketone (PEEK) by Sulfuric Acid and Piranha Solution: Influence of the Modification Route in Capacity for Inducing Cell Growth.

The aim of this study was to promote bioactivity of the PEEK surface using sulfuric acid and piranha solution. PEEK was functionalized by a sulfuric acid treatment for 90 s and by piranha solution for 60 and 90 s. Chemical modification of the PEEK surface was evaluated by infrared spectroscopy, contact angle analysis, cytotoxicity, cell adhesion and proliferation. The spectroscopy characteristic band associated with sulfonation was observed in all treated samples. PEEK with piranha solution 60 s showed an increase in the intensity of the bands, which was even more significant for the longer treatment (90 s). The introduction of the sulfonic acid functional group reduced the contact angle. In cytotoxicity assays, for all treatments, the number of viable cells was higher when compared to those of untreated PEEK. PEEK treated with sulfuric acid and piranha solution for 60 s were the treatments that showed the highest percentage of cell viability with no statistically significant differences between them. The modified surfaces had a greater capacity for inducing cell growth, indicative of effective cell adhesion and proliferation. The proposed chemical modifications are promising for the functionalization of PEEK-based implants, as they were effective in promoting bioactivation of the PEEK surface and in stimulating cell growth and proliferation.

Cytotoxicity determination of nano-zinc oxide eugenol on human gingival fibroblast cells

Zinc oxide eugenol (ZOE) is composed of approximately 70% ZnO and approximately 30% eugenol. ZOE has been used in dentistry as a temporary filler, cavity liner, and base for tooth cavities. It is used to form a thin layer of cement to protect the pulp from any influx of bacteria or irritants present in the tooth cavity. Such bacteria and irritants can lead to the formation of an abscess or pus in the gums or periapical tissues. As ZnO has antibacterial effects, it is appropriate to use ZOE as a temporary filler, liner, or base. On the other hand, eugenol alone is acidic and may leach out to have adverse effects on the periapical tissue. Therefore, the toxicity level of ZOE is important to avoid adverse effects or unnecessary dosing. Thus, in the present study, we investigated the potential toxicity of ZOE leaching toward human gingival fibroblast tissue to verify its safety and efficacy by using ZnO particles with different morphologies and sizes. Three types of ZnO powder were used in this study: ZnO-A and ZnO–B (which were produced using the French process) and ZnO–K, which are commercial particles used for ZOE temporary fillers. All three types of ZnO were mixed with eugenol to form ZOE. Then, all three types were characterised to determine their morphology, particle size, and specific surface area. Each type of ZnO was then mixed with resin-bonded eugenol to obtain ZOE pellets. Subsequently, the toxicology of the ZOE leachings was tested on human gingival fibroblast cells using a calorimetric assay for 24 and 48 h. The results show that ZnO-A, ZnO–B, and ZnO–K have particle sizes of 22.3, 48.33, and 1196 nm, respectively. The specific surface areas were 4.44, 3.89, and 0.74 m2/g, respectively. Moreover, the toxicology of the ZOE leachings revealed a lower percentage of viable cells with an increase in the leaching concentration. After 24 and 48 h of cytotoxicity tests, the percentage of viable cells decreased slightly with leaching concentrations of 10%–40% and decreased considerably with leaching concentrations of 50%–100%. This shows that the viable cell percentage depends on the leaching concentration and duration of the exposure. Moreover, the results show that smaller particles have larger specific surface areas and higher percentages of viable cells. This means that the smaller particles released smaller amounts of eugenol and Zn2+ during the toxicity evaluation, which led to less reactive oxygen species (ROS) production and influenced the number of cells that survived after 24 and 48 h.

Effects of different detergent-containing children's toothpastes on the viability, osteogenic and chondrogenic differentiation of human dental periodontal ligament stem cells and gingival stem cells in vitro

BackgroundDetergents are the most commonly used compounds in toothpastes due to their foaming and cleaning peoperties. This study aimed to investigate the effects of children’s toothpastes with different detergent content on the viability, the osteogenic and chondrogenic differentiation potentials of human mesenchymal stem cells. MethodsThe necessary tissues for human periodontal ligament mesenchymal stem cells (hPDLMSCs) and human gingival mesenchymal stem cells (hGMSCs) isolation were obtained during extraction of 10 impacted third molar teeth. The viability of the cells stimulated with different concentratiaons of Colgate, Sensodyne, Splat, Nenedent, Perlodent toothpaste solutions and complete Dulbocco’s modified eagle medium (control group) were evaluated by using the flow cytometer. In addition, the osteogenic and chondrogenic differentiation potential of human gingival and periodontal ligament mesenchymal stem cells exposed to toothpaste solutions were examined morphologically. Datas were analyzed with IBM SPSS V23. One way ANOVA test was used to determine the differences between the groups for multiple comparisons, while the Tukey post-hoc test was used for pair wise comparisons in determining which groups differed. ResultsA higher percentage of cell viability was detected in Control group at 20 %, 50 % and 80 % (p = 0.000) on hGMSCs. After the Control group, the highest cell viability ratios were observed in the detergent-free Splat group (p = 0.000) followed by the Sensodyne experimental group containing CABP (p = 0.000). While the cell viability rates in Nenedent group was found significantly higher than the Perlodent group at other concentrations except for 20 % concentration (p = 0.000). Colgate group had the lowest percentage of cell viability among the experimental groups at all concentrations on hPDMSCs (p = 0.000). The highest live cell ratios was detected in Control group (p = 0.000), followed by Splat and Sensodyne groups (p = 0.000). The cell viability ratios at 50 % concentration were higher in Perlodent group than Nenedent group (p = 0.000). The highest osteogenic and chondrogenic differentiation potential of mesenchymal stem cells stimulated with different toothpaste was determined in Control and Splat group. ConclusionsAs a result of the findings, it was observed that toothpaste containing SLS had a more negative effect on the viability of the cells and the differentiation potentials than the other groups.

Radiation-induced graft polymerization of elastin onto polyvinylpyrrolidone as a possible wound dressing.

The purpose of our study was to obtain new wound dressings in the form of hydrogels that promote wound healing taking advantage of the broad activities of elastin (ELT) in physiological processes. The hydrogel of ELT and polyvinylpyrrolidone (PVP; ELT-PVP) was obtained by cross-linking induced by gamma irradiation at a dose of 25 kGy. The physicochemical changes attributed to cross-linking were analyzed through scanning electron microscopy (SEM), infrared spectroscopy analysis with Fourier transform (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Furthermore, we performed a rheological study to determine the possible changes in the fluidic macroscopic properties produced by the cross-linking method. Finally, we accomplished viability and proliferation analyses of human dermal fibroblasts in the presence of the hydrogel to evaluate its biological characteristics. The hydrogel exhibited a porous morphology, showing interconnected porous with an average pore size of 16 ± 8.42 µm. The analysis of FTIR, DSC, and TGA revealed changes in the chemical structure of the ELT-PVP hydrogel after the irradiation process. Also, the hydrogel exhibited a rheological behavior of a pseudoplastic and thixotropic fluid. The hydrogel was biocompatible, demonstrating high cell viability, whereas ELT presented low biocompatibility at high concentrations. In summary, the hydrogel obtained by gamma irradiation revealed the appropriate morphology to be applied as a wound dressing. Interestingly, the hydrogel exhibited a higher percentage of cell viability compared with ELT, suggesting that the cross-linking of ELT with PVP is a suitable strategy for biological applications of ELT without generating cellular damage.

Cytotoxicity of oregano essential oil and calcium hydroxide on L929 fibroblast cell: A molecular level study.

Introduction:The purpose of antimicrobial agents is to eliminate the microorganisms without causing toxicity to host cells. This study aimed to assess the cytotoxic effect of oregano essential oil on L929 fibroblast cells.Materials and Methods:L929 fibroblast cells were exposed to four different concentrations of oregano essential oil (25–200 μg/ml) and calcium hydroxide (1 mg/ml). Dose-response curve was evaluated using 3-(4,5 dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. The toxicity of L929 fibroblast cells was determined by lactate dehydrogenase activity (LDH). The results were analyzed using one-way analysis of variance and turkey post hoc test. P <0.05 was considered statistically significant.Results:Oregano essential oil showed a higher percentage of cell viability than the calcium hydroxide group. At 50 μg/ml, fibroblast cells showed arbitrarily 80% of cell viability compared to calcium hydroxide. There was a statistically significant difference with P < 0.05 on evaluating the effect of oregano essential oil on cytotoxicity measurement by LDH release of L929 fibroblast cells.Conclusion:Within the limitation of the study, Oregano essential oil at 50 μg/ml reported to show reduced cytotoxicity compared to calcium hydroxide at 1 mg/ml. Therefore, perhaps after evaluating other properties, it might be considered an intracanal medicament.

GFc7 as a Smart Growth Nanofactor for ex vivo Expansion and Cryoprotection of Humans' Hematopoietic Stem Cells.

BackgroundNowadays, smart synthesized nanostructures have attracted wide attention in the field of stem cell nanotechnology due to their effect on different properties of stem cells.MethodsGFc7 growth nanofactor was synthesized based on nanochelating technology as an iron-containing copper chelator nanocomplex. The effect of this nanocomplex on the expansion and differentiation of hematopoietic stem cells (HSCs) as well as its performance as a cryoprotectant was evaluated in the present study.ResultsThe results showed that the absolute count of CD34+ and CD34+CD38− cells on days 4, 7, 10 and 13; the percentage of lactate dehydrogenase enzyme on the same days and CD34+CXCR4 population on day 10 were significantly increased when they were treated with GFc7 growth nanofactor in a fetal bovine serum (FBS)-free medium. This medium also led to delayed differentiation in HSCs. One noticeable result was that CD34+CD38− cells cultured in an FBS medium were immediately differentiated into CD34+CD38+ cells, while CD34+CD38− cells treated with GFc7 growth nanofactor in FBS medium did not show such an immediate significant differentiation. De-freezing GFc7-treated CD34+ cells, which were already frozen according to cord blood bank protocols, showed a higher percentage of cell viability and a larger number of colonies according to colony-forming cell assay as compared to control.ConclusionIt can be claimed that treating HSCs with GFc7 growth nanofactor leads to quality and quantity improvement of HSCs, both in terms of expansion in vitro and freezing and de-freezing processes.