In vitro inhibitory effect of trichostatin A on canine grade 3 mast cell tumor

Mast cell tumor (MCT) is one of the most prevalent neoplasms that affect skin and soft tissue in dogs. Because mast cell tumors present a great variety of clinical appearance and behavior, their treatment becomes a challenge. Trichostatin A (TSA), an antifungal antibiotic, has shown inhibitory effects on the proliferation and induction of apoptosis in various types of cancer cells. In order to evaluate the potential of trichostatin A as a therapeutic drug, cells of grade 3 MCT were cultured and treated with concentrations of 1 nM to 400 nM of TSA. MTT assay and trypan blue exclusion assays were performed to estimate cell growth and cell viability, and cell cycle analysis was evaluated. TSA treatment showed a reduction in numbers of viable cells and an increase of cell death by apoptosis. The cell cycle analysis showed an increase of hypodiploid cells and a reduction of G0/G1 and G2/M -phases. According to these results, trichostatin A may be an interesting potential chemotherapeutic agent for the treatment of canine MCT.

Immobilized Kidney 28-kDa Endostatin- Related (KES28kDa) Fragment Promotes Endothelial Cell Survival

Background/Objective: Renal ischemia-hypoxia is a leading cause of acute kidney injury (AKI). Ischemia causes extracellular matrix breakdown of the tubular basement membrane. Endostatin (ES) is the C-terminal fragment of collagen XVIII generated by proteolytic cleavage. Recent studies have demonstrated that ES expression is upregulated in ischemic kidneys. The present study aimed to characterize ES from ischemic kidneys. Methods: Ischemic renal failure was induced via 45 min of occlusion of the left renal artery and vein. After the ischemic period, blood was collected. Kidneys were harvested and used for immunohistochemical testing and protein extraction. Three-step purification was used. Soluble and immobilized purified ES were tested in cell viability and adhesion assays. Results: The soluble KES28kDa inhibited endothelial cell proliferation: 25 versus 12.5 mu g (p < 0.05); 12.5 versus 3.15 mu g (p < 0.05). Immobilization of KES28kDa supports endothelial cell survival over the control p = 0.021). Human umbilical vein endothelial cells plated on immobilized KES28kDa showed an increase in membrane ruffles and stress fibers. Conclusion: These data demonstrate the local synthesis of a 28-kDa ES-related fragment following AKI and suggest its role in endothelium survival. Copyright (C) 2010 S. Karger AG, Basel

Effect of cold storage on culture viability and some rheological properties of fermented milk prepared with yogurt and probiotic bacteria

We examined the effect of storage time on culture viability and some rheological properties (yield stress, storage modulus, loss modulus, linear viscoelastic region, structural recuperation and firmness) of fermented milk made with Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus acidophilus (LA) and Bifidobacterium animalis ssp. lactis in coculture with Streptococcus thermophilus (ST). Acidification profiles and factors that affect viability (postfermentation acidification, acidity and dissolved oxygen) were also studied during 35 days at 4C. Fermented milk prepared with a coculture of ST and Bifidobacterium lactis gave the most constant rheological behavior and the best cell viability during cold storage; it was superior to ST plus LA for probiotic fermented milk production.

Toxicogenomic activity of gemcitabine in two TP53-mutated bladder cancer cell lines: special focus on cell cycle-related genes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of castor oil-based polyurethane membranes in rat bone-marrow cell culture

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vitro cultivation of canine multipotent mesenchymal stromal cells on collagen membranes treated with hyaluronic acid for cell therapy and tissue regeneration

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Viability of human fibroblasts in coconut water as a storage medium

P>AimTo evaluate the effectiveness of a new storage medium for avulsed teeth, coconut water, in maintaining the viability of human fibroblasts.MethodologyCell viability after different time periods was evaluated in the following storage media: coconut water, coconut water with sodium bicarbonate, milk, saline and still mineral water. Human fibroblasts were seeded in Eagle's minimal essential medium (EMEM) supplemented with 7.5% foetal calf serum. After trypsinisation, 100 mu L of culture medium containing approximately 10(4) cells mL(-1) were collected and pipetted into the wells of 96-well plates, which were incubated overnight in 5% CO(2) and 95% air mixture at 37 degrees C. EMEM was then replaced by the storage media and the plates were incubated at 37 degrees C for 1, 2 and 4 h. Cell viability was determined using the neutral red assay. The proportions of viable cells after exposure to the storage media were analysed statistically by anova and the least significant difference (LSD) test (alpha = 5%).ResultsMilk had the greatest capacity to maintain cell viability (P < 0.05), followed by coconut water with sodium bicarbonate and saline. Coconut water was significantly worse at maintaining cell viability compared to milk, coconut water with sodium bicarbonate and saline. The smallest number of viable cells was observed for mineral water (P < 0.05).ConclusionCoconut water was worse than milk in maintaining human fibroblast cell viability.

Effects of low-level laser therapy (685 nm) at different doses in osteogenic cell cultures

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cytotoxicity of Portland Cement with Different Radiopacifying Agents: A Cell Death Study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genotoxic, mutagenic and cytotoxic effects of the commercial dye CI Disperse Blue 291 in the human hepatic cell line HepG2

Textile dyes are discarded into the aquatic ecosystem via industrial effluents and potentially expose humans and local biota to adverse effects. The commercial dye CI Disperse Blue 291 which contains the aminoazobenzene 2-[(2-bromo-4,6-dinitrophenyl)azo]-5(diethylamino)-4-methoxyacetanilide (CAS registry no. 56548-64-2), was tested for genotoxicity and cytotoxicity in the human hepatoma cell line HepG2, using the comet assay, micronucleus (MN) test and a cell viability test. Five different concentrations of the test compound were examined: 200 mu g/ml, 400 mu g/ml, 600 mu g/ml, 800 mu g/ml and 1000 mu g/ml. An increase in comet tail length and in the frequency of MN was detected with exposure of cells to concentrations of the commercial dye from 400 pg/ml. Furthermore, the dye was found to decrease cell viability. The results of this study demonstrate for the first time the genotoxic and mutagenic effects of the dye CI Disperse Blue 291 in mammalian cells, thus stressing the need to develop non-mutagenic dyes and to invest in improving the treatment of effluents. These measures will help to prevent harmful effects that these compounds can have on humans and aquatic organisms that come in contact with them. (C) 2007 Elsevier Ltd. All rights reserved.

Markers of cell death in salivary glands of males of the tick Rhipicephalus sanguineus (Latreille, 1806) (Acari, Ixodidae)

The salivary glands of Rhipicephalus sanguineus males at stages: unfed (control), at day seven post-attachment, and at days three and seven post-detachment from the host were examined using methods of enzymatic analysis and cell viability. At these stages of feeding, different staining patterns were observed in the cells of type IV, III, II and I acini, which were affected by degeneration in this sequence. Acid phosphatase reaction was inversely proportional to that of ATPase, while ATPase reaction was proportional to membrane integrity.Salivary gland cells of unfed males exhibited intact nucleus and plasma membrane, suggesting that the acid phosphatase detected may participate in the normal physiology of acini. In males at day seven post-attachment, intact membranes were observed in almost all types of acini, as well as stronger reaction for acid phosphatase, nuclear changes, and decrease in ATPase reaction, changes associated with the degenerative process. At days three and seven post-detachment degeneration progress, being observed loss of membrane integrity, nuclear changes, prominent decrease in ATPase reaction, and an increase in acid phosphatase reaction in the first case and a decreased of it at day seven post-detachment from the host. During cell death, alterations occurred in the following sequence: a) nuclear changes, b) loss of ATPase reaction, c) loss of integrity of the plasma membrane, and d) increase of acid phosphatase. The latter might be associated with the late degradation of cytoplasmic remnants, characterizing the process of cell death in glands of R. sanguineus males as atypical or non-classic apoptosis. (C) 2008 Elsevier B.V. All rights reserved.

GROWTH AND FERMENTATION CHARACTERISTICS OF NEW SELECTED STRAINS OF SACCHAROMYCES AT HIGH-TEMPERATURES AND HIGH CELL DENSITIES

Maintenance of high cell viability was the main characteristic of our new strains of thermotolerant Saccharomyces. Total sugar conversion to ethanol was observed for sugarcane juice fermentation at 38-40-degrees-C in less than 10 h and without continuous aeration of the culture. Invertase activity differed among the selected strains and increased during fermentation but was not dependent on cell viability. Invertase activity of the cells and optimum temperature for growth, as well as velocity of ethanol formation, were dependent on medium composition and the type of strain used. At high sugarcane syrup concentrations, the best temperature for ethanol formation by strain 781 was 35-degrees-C. Distinct differences among the velocities of ethanol production using selected strains were also observed in sugarcane syrup at 35-38-degrees-C.

Evaluation of the Effects of Endodontic Materials on Fibroblast Viability and Cytokine Production

Introduction: Recently, a new sealer composed of Portland cement named Endo-CPM-Sealer was developed. The aim of this study was to investigate the effects of Endo-CPM-Sealer (EGEO SRL, Buenos Aires, Argentina), Sealapex (Sybron Endo, Glendora, CA), and Angelus MTA (Angelus, Londrina, Brazil) on cell viability and cytokine (interleukin [IL]-1 beta and IL-6) production by mouse fibroblasts. Methods: Millipore culture plate inserts with polyethylene tubes filled with materials were placed into 24-well cell culture plates with mouse fibroblasts. Cells cultured with only empty polyethylene tubes were used as the control. After 24 hours, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay was used to evaluate the cell viability. For cytokine assay, mouse fibroblasts were incubated in 24-well flat-bottom plates with set material disks at the bottom. Cells cultured without the material disks served as the negative control. After 24 hours of incubation, culture media were collected for cytokine evaluation by using an enzyme-linked immunosorbent assay. The data were statistically analyzed by analysis of variance and Bonferroni correction. Results: Endo-CPM-Sealer, Sealapex, and Angelus MTA did not inhibit the cell viability. All materials induced IL-6 releasing, but the amount was not statistically significant compared with the control group. Angelus MTA induced IL-1 beta releasing significantly more than the control. Conclusions: All materials were not considered cytotoxic in fibroblast culture. (J Endod 2009;35:1577-1579)

Candida albicans inactivation and cell membrane integrity damage by microwave irradiation

In indicating the microwave irradiation for disinfecting dentures it is necessary to see how this procedure influences Candida albicans integrity and viability. The aim of this study was to evaluate the ability of microwaves to inactivate C. albicans and damage cell membrane integrity. Two 200-ml C. albicans (ATCC 10231) suspensions were obtained. A sterile denture was placed in a beaker containing the Experimental (ES) or the Control suspension (CS). ES was microwaved at 650 W for 6 min. Suspensions were optically counted using methylene blue dye uptake as indicative of membrane-damaged cells; spread on Agar Sabouraud dextrose (ASD) for viability assay; or spectrophotometrically measured at 550 nm. Cell-free solutions were submitted to content analyses of protein (Bradford and Pyrogallol red methods); Ca++ (Cresolftaleine complexone method); DNA (spectrophotometer measurements at 260 nm) and K + (selective electrode technique). Data were analysed by Student's t- or Wilcoxon z-tests (α = 0.05). All ES cells demonstrated cell membrane damage. Viable cells were non-existent in the ES ASD plates. No significant difference in optical density between ES and CS was observed (P = 0.272). ES cells released significantly high protein (P < 0.001, Bradford; P = 0.005, Pyrogallol red), K+ (P < 0.001), Ca++ (P = 0.012) and DNA (P = 0.046) contents. Microwaves inactivated C. albicans and damaged cell membrane integrity. © 2007 The Authors.

A hydrogel scaffold that maintains viability and supports differentiation of dental pulp stem cells

Objectives: The clinical translation of stem cell-based Regenerative Endodontics demands further development of suitable injectable scaffolds. Puramatrix™ is a defined, self-assembling peptide hydrogel which instantaneously polymerizes under normal physiological conditions. Here, we assessed the compatibility of Puramatrix™ with dental pulp stem cell (DPSC) growth and differentiation. Methods: DPSC cells were grown in 0.05-0.25% Puramatrix™. Cell viability was measured colorimetrically using the WST-1 assay. Cell morphology was observed in 3D modeling using confocal microscopy. In addition, we used the human tooth slice model with Puramatrix™ to verify DPSC differentiation into odontoblast-like cells, as measured by expression of DSPP and DMP-1. Results: DPSC survived and proliferated in Puramatrix™ for at least three weeks in culture. Confocal microscopy revealed that cells seeded in Puramatrix™ presented morphological features of healthy cells, and some cells exhibited cytoplasmic elongations. Notably, after 21 days in tooth slices containing Puramatrix™, DPSC cells expressed DMP-1 and DSPP, putative markers of odontoblastic differentiation. Significance: Collectively, these data suggest that self-assembling peptide hydrogels might be useful injectable scaffolds for stem cell-based Regenerative Endodontics. © 2012 Academy of Dental Materials.