Fibroblast Cell Line L929 Research Articles

Biocompatibility of pristine graphene monolayer: Scaffold for fibroblasts

The aim of the present study was to evaluate the cytotoxicity of pristine graphene monolayer and its utility as a scaffold for murine fibroblast L929 cell line. Cell viability, morphology, cytoskeleton architecture (microfilaments and microtubules), cell adhesion and migration into the scratch-wound area were determined using pristine graphene-coated microscopic slides. We found that fibroblasts cultured on pristine graphene monolayer exhibited changes in cell attachment, motility and cytoskeleton organization. Graphene was found to have no cytotoxicity on L929 fibroblasts and increased cell adhesion and proliferation within 24 h of culture. The area of cells growing on graphene was comparable to the area of fibroblasts cultured on glass. Migration of cells on the surface of graphene substrate appeared to be more regular in comparison to uncoated glass surface, however in both control (glass) and experimental (graphene) groups the scratch wound was closed after 48 h of culture. Taken together, our results indicate that pristine graphene monolayer is non-toxic for murine subcutaneous connective tissue fibroblasts and could be beneficial for recovery of damaged tissues after injury. These studies could be helpful in evaluating biocompatibility of graphene, which still remains ambiguous.

New Antiproliferative Polyunsaturated Epoxy-Heneicosane Derivatives Isolated from the Brown Alga Lobophora variegata

Two new polyunsaturated 3,4-epoxy-heneicosane derivatives named as epoxy-lobophorene A and epoxy-lobophorene B were isolated from the brown alga Lobophora variegata, in addition to nine known compounds. The structures of the new compounds were elucidated using a combination of 1D/2D nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HRMS). The isolated compounds were submitted to antiproliferative assays against the human colon cancer cell line HCT-116, human metastatic prostate cancer PC-3M, murine metastatic melanoma B16-F10 and murine fibroblast cell line L929 and also tested as antibacterial. Both 3,4-epoxy lobophorene A and 3,4-epoxy lobophorene B depicted moderate antiproliferative effect against cell lines. None of them showed antibacterial activity.

Phosphorus-nitrogen compounds. part 38. Syntheses, characterizations, cytotoxic, antituberculosis and antimicrobial activities and DNA interactions of spirocyclotetraphosphazenes with bis-ferrocenyl pendant arms

The reactions of N4P4Cl8 (1), with two equimolar amounts of N-(1-ferrocenylmethyl)-N-methyl-propylenediamine gave the monoferrocenyl-spiro (as a byproduct), bisferrocenyl-2-trans-6-dispiro (2) and bisferrocenyl-2-cis-6-dispiro (3) cyclotetraphosphazenes. The 2-trans-6-dispiro (2) was reacted with excess monoamines to produce the tetraamino products (2a-2d). The one equimolar amount of the diamines and dialkoxides with 2 afforded the mono-diamino (2e and 2f) and mono-dialkoxy (2g and 2h) cyclotetraphosphazenes. Whereas, excess diamines and dialkoxides with 2 produced the bis-diamino (2i and 2j) and bis-dialkoxy (2k and 2l) bisferrocenyl-2-trans-6-dispirocyclotetraphosphazenes. The structures of the compounds were verified by elemental analyses, ESI-MS, FTIR, HSQC, HMBC, 1H, 13C, and 31P NMR techniques. The molecular structures of 2 and 2b were established by X-ray crystallography. Compounds 2e and 2f have two stereogenic P-atoms. Additionally, the structures of 2i-2l containing tetraspiro rings in the skeletons look similar a propeller. The Fc groups of the cyclotetraphosphazenes were found to be redox active with two-reversible electron oxidations. The antimicrobial activity of the compounds was examined against some bacteria and yeast strains. The interactions of the compounds with DNA revealed that the compounds caused conformational changes even strand break on supercoiled DNA helix. Furthermore, the compounds (except 2, 2a and 2d) inhibited DNA restriction indicating compounds binding to A/A and G/G nucleotides of the DNA. The evaluations of the cytotoxic activity against L929 fibroblast and DLD-1 colon cancer cell lines were carried out. Some of the compounds were evaluated for antituberculosis activity against reference strain Mycobacterium tuberculosis H37Rv, and 2i and 2l displayed antituberculosis activity against H37Rv.

Ozonated Olive Oil with a High Peroxide Value for Topical Applications: In-Vitro Cytotoxicity Analysis with L929 Cells

ABSTRACTPrevious studies have shown that ozonated vegetable oils have been used topically for healing of cutenous wounds. The aim of this study is to evaluate the dose dependent use of ozonated olive oil with high peroxide value (OZ) on the viability of cells for preventing side effects in topical applications. To the best of our knowledge, there are no reports investigaing the effect of peroxide value of ozonated olive oil associated with its cytotoxic activity on mouse non-neoplastc fibroblast cell lines (L929). Therefore, the present study was carried out by using OZ alone and/or in combination with glycerol and olive oil. In our study OZ was prepared by using pure olive oil. Both olive oil and glycerol are non-toxic and can be mixed with OZ uniformly. The cytotoxic activity of samples against L929 fibroblasts was assessed using the tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT) assay. The peroxide value of synthesized OZ was found to be in the range of 2700–2900 mEq O2/kg oil. The OZ/olive oil group did not show any cell death at all concentrations tested (p > 0.05) however OZ/glycerol group showed statistically significant reductions in viability at higher concentrations (p = 0.004–0.006) compared to the control group. Conclusively, using OZ/olive oil with a peroxide value of 2700–2900 mEq O2/kg oil for short-term incubation was non-cytotoxic to the L929 fibroblast cell line.

Green synthesis of silver nanoparticles by Ricinus communis var. carmencita leaf extract and its antibacterial study

In this study, we report synthesis of silver nanoparticles (RcAgNPs) from silver nitrate solution using methanolic leaf extract of Ricinus communis var. carmencita. The polyphenols present in the leaves reduce Ag++ ions to Ag0 followed by a color change. Silver nanoparticle formation was ensured by surface plasmon resonance between 400 nm to 500 nm. Crystallinity of the synthesized nanoparticles was confirmed by UHRTEM, SAED and XRD analysis. The capping of phytochemicals and thermal stability of RcAgNPs were assessed by FTIR spectra and TGA analysis, respectively. It also showed antibacterial activity against both gram positive and gram negative strains. RcAgNPs were non-toxic against normal cell line (mouse fibroblast cell line L929) at lower concentrations (80 µg ml−1).

In Vitro Biocompatibility and Macrophage Uptake Assays of Poly(Urea-Urethane) Nanoparticles Obtained by Miniemulsion Polymerization

In this work In Vitro cytotoxicity of poly(urea-urethane) nanoparticles obtained by miniemulsion polymerization against murine fibroblast (L929), normal human fibroblast (NIH3T3) and MRC-5 cell line derived from normal lung tissue, as well as, hemocompatibility, and In Vitro macrophage uptake were evaluated. From the results obtained in this work, poly(urea-urethane) nanoparticles showed spherical morphology, negative zeta potential and mean diameter of 85 ± 4 nm. In Vitro cytotoxicity against fibroblast cell lines L929, NIH-3T3, and MCR-5 showed no reduction of cell viability, which is a critical parameter for the drug carrier biocompatibility. In addition, in In Vitro macrophage uptake studies, poly(urea-urethane) nanoparticles showed a high phagocytic uptake, 72%. Hemolysis assays showed high human blood biocompatibility and the results indicate that poly(urea-urethane) nanoparticles obtained in this work have excellent properties without secondary effect, with potential application as carrier for drug delivery in the treatment of diseases in which macrophages act as host cells.

Carbon Nanotube-Hydroxyapatite Composite for Bone Tissue Engineering and Their Interaction with Mouse Fibroblast L929 In Vitro

Bone injuries and defects are therapeutically challenging. Autografts and allografts are ideal treatment approaches for bone regeneration, but, they are coupled with a number of complications, and variable outcomes. Bone substitute biomaterials, have shown great potential for bone tissue engineering application. Which not only efficiently solved the problem of limited supply, but also provided possibility for reducing immune-complications and enhanced bone formation. Hydroxyapatite (HA) has been used in clinical bone graft procedures for more than 25 years. However, its poor tensile strength and fracture toughness compared with bone make it unsuitable for major loadbearing devices. Carbon nanotubes (CNTs), with their high aspect ratio and excellent mechanical properties, have the potential to strengthen and toughen Hydroxyapatite (HA) without offsetting its bioactivity, thus it has been a significant challenge to the application of HA for the replacement of load-bearing and/or large bone defects. The main aim of the study is to functionalized the MWCNT to attach functional groups to the nanostructure. These functionalized nanoparticles then reinforce with HA to make MWCNT-HA nanocomposites. Further, these nanocomposites are tested for its biocompatibilities with mouse fibroblast cell lines L929 in vitro. The functionalization of MWCNTs with acid mixture appends the functional groups to the structure, called as functionalized MWCNTs. These functionalized CNTs is now ready to interact with other materials to form a composite. We reinforced these functionalized CNTs with HA in situ, that leads to synthesis of MWCNT-HA composite. Furthermore, this study investigates the cytotoxic effects of functionalized Multiwalled Carbon nanotubes (f-MWCNTs) and its composites with HA in L929 mouse fibroblast cell line. FTIR analysis confirms the attachments of different functional group e.g., –C–O–, C O, –COOH to the composite. The FESEM image confirms the physical interaction of HA and CNT. The Interaction of these material with L929 cell lines shows no detrimental effects.

Biosynthesis of Silver Nanoparticles from Protium serratum and Investigation of their Potential Impacts on Food Safety and Control.

Silver nanoparticles play an integral part in the evolution of new antimicrobials against the broad ranges of pathogenic microorganisms. Recently, biological synthesis of metal nanoparticles using plant extracts has been successfully consummated. In the present study, the biosynthesis of silver nanoparticles (AgNPs) was conducted using the leaf extract of plant Protium serratum, having novel ethnomedicinal. The synthesized AgNPs were characterized using UV-Visible spectroscopy, dynamic light scattering spectroscopy (DLS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy. The DLS study revealed the surface charge of the resulted nanoparticles that was highly negative, i.e., −25.0 ± 7.84 mV and the size was 74.56 ± 0.46 nm. The phytochemical and FTIR analysis confirmed the role of water-soluble phyto-compounds for the reduction of silver ions to silver nanoparticles. The potential antibacterial activity of AgNPs was studied against the food borne pathogens viz. Pseudomonas aeruginosa (IC50 = 74.26 ± 0.14 μg/ml), Escherichia coli (IC50 = 84.28 ± 0.36 μg/ml), Bacillus subtilis (IC50 = 94.43 ± 0.4236 μg/ml). The in vitro antioxidant potential of AgNPs was evaluated using 1, 1-diphenyl-2-picryl-hydrazil (IC50 = 6.78 ± 0.15 μg/ml) and hydroxyl radical assay (IC50 = 89.58 ± 1.15 μg/ml). In addition, the cytotoxicity of AgNPs was performed against fibroblast cell line L-929 to evaluate their biocompatibility. The overall results of the present investigation displayed the potential use of P. serratum leaf extract as a good bio-resource for the biosynthesis of AgNPs and their implementation in diverse applications, specifically as antibacterial agent in food packaging and preservation to combat against various food borne pathogenic bacteria along with its pharmaceutical and biomedical applications.

Synthesis and characterization of glycyrrhizic acid coated iron oxide nanoparticles for hyperthermia applications

In the present study, iron oxide magnetic nanoparticles (IONPs) were synthesized using the oxidative precipitation method for biomedical applications. Glycyrrhizic acid (GA) extracted from the roots of licorice plant was used as the coating agent for the synthesized nanoparticles (GAIONPs). The crystal phase, morphology and size were investigated by XRD, FE-SEM and TEM. The saturation magnetization (ms) value of the nanoparticles was measured by VSM indicating lowered ms of the GAIONPs with respect to that of the IONPs due to the presence of GA. In addition, the specific loss power of nanoparticles in a solution and in a tissue mimicking phantom was measured using an alternating magnetic field generator. The presence of the GA on the crystal surface was further confirmed using FT-IR and TG/DTA measurements. The specific surface area of the nanoparticles was measured by BET indicating that GA coating agent increases the available active surface area of the nanoparticles for about 25% making it more appropriate for drug loading purposes. The cytotoxicity of the nanoparticles was investigated using MTT assay on L929 fibroblast cell line and the results demonstrated that the coating agent enhances the biocompatibility of the IONPs. The effectiveness of the nanoparticles in inducing cell death was also assessed in an in vitro hyperthermia process and the results showed that the nanoparticles are appropriate to be used for cancer treatment based on hyperthermia.

Studies on wound healing potential of polyherbal formulation using in vitro and in vivo assays

BackgroundThe use of herbal plant extracts in wound healing is known through decades, but it is necessary to provide scientific data through reverse pharmacology. ObjectiveThe aim of the present study is to find the mechanism behind the healing of wounds using in vitro and in vivo assays. Material and methodsThe study was designed to determine proliferation and mobilization of fibroblast and keratinocytes at the site of injury, angiogenesis at the site of healing and reduction in oxidative stress while healing. In our earlier studies it was observed that herbal extract of Vitex negundo L. (VN), Emblica officinalis Gaertn (EO), and Tridax procumbens L. (TP) showed rapid regeneration of skin, wound contraction and collagen synthesis at the site of injury in excision wound model. In the present study the cell mobilization was monitored in the scratch assay on L929 fibroblastic cell line and HaCaT keratinocytes cell line under the influence of aqueous plant extracts and its formulation. This formulation was also assessed for its angiogenic potential using CAM assay. Study was carried out to probe synergistic effect of polyherbal formulation using excision model in rat. ResultsThe formulation was found to contain high amount of flavonoids, tannins and phenols which facilitate wound healing. At 20 μg/ml concentration of formulation, significant increase in tertiary and quaternary vessels were observed due to angiogenic potential of formulation. Formulation at the concentration of 3 μg/ml and 5 μg/ml showed significant mobilization of keratinocytes and fibroblasts respectively at the site of injury. Polyherbal formulation showed rapid regeneration of skin and wound contraction. Biochemical parameters like hydroxyproline, hexosamine and collagen turnover was increased in test drug treated animals as compared to untreated, whereas antioxidants such as catalase and GSH were increased significantly and decreased amount of tissue MDA was observed. ConclusionPolyherbal formulation prepared from the plant extracts accelerates wound healing process by proliferation and mobilization of fibroblast and keratinocytes, and angiogenesis at the site of injury. It also shows fast contraction of wound with its beneficial improvement in tissue biochemical and antioxidant parameters.

Preparation of collagen/polyurethane/knitted silk as a composite scaffold for tendon tissue engineering.

The main objective of this study was to prepare a hybrid three-dimensional scaffold that mimics natural tendon tissues. It has been found that a knitted silk shows good mechanical strength; however, cell growth on the bare silk is not desirable. Hence, electrospun collagen/polyurethane combination was used to cover knitted silk. A series of collagen and polyurethane solutions (4%-7% w/v) in aqueous acetic acid were prepared and electrospun. According to obtained scanning electron microscopy images from pure collagen and polyurethane nanofibers, concentration was set constant at 5% (w/v) for blend solutions of collagen/polyurethane. Afterward, blend solutions with the weight ratios of 75/25, 50/50 and 25/75 were electrospun. Scanning electron microscopy images demonstrated the smooth and uniform morphology for the optimized nanofibers. The least fibers diameter among three weight ratios was found for collagen/polyurethane (25/75) which was 100.86 ± 40 nm and therefore was selected to be electrospun on the knitted silk. Attenuated total reflectance-Fourier transform infrared spectra confirmed the chemical composition of obtained electrospun nanofibers on the knitted silk. Tensile test of the specimens including blend nanofiber, knitted silk and commercial tendon substitute examined and indicated that collagen/polyurethane-coated knitted silk has appropriate mechanical properties as a scaffold for tendon tissue engineering. Then, Alamar Blue assay of the L929 fibroblast cell line seeded on the prepared scaffolds demonstrated appropriate viability of the cells with a significant proliferation on the scaffold containing more collagen content. The results illustrate that the designed structure would be promising for being used as a temporary substitute for tendon repair.

Metal Ion Release and Cytotoxicity of Titanium Orthodontic Miniscrews

The aim of this study was to investigate the metal ion release and cytotoxicity of MU orthodontic miniscrews as well as two other brands of orthodontic miniscrews over time. Twenty-four orthodontic miniscrews were tested, divided into three groups of eight. Each sample extraction was performed following the ISO 10993-12:2012 method. Solutions were collected after 1, 7, and 30 days (T1, T2, and T3). The supernatants extracted from these three groups were added and exposed to mouse L929 fibroblastic cell line using an MTT cytotoxicity test. They were also tested for ion release by inductively coupled plasma-mass spectrometry (ICP-MS). Element analysis by energy-dispersive X-ray spectroscopy (EDS) was used to analyze the surfaces of the miniscrews. The quantification of three elements, namely, titanium (Ti), aluminum (Al), and vanadium (V) were assessed. The results indicated that there were no statistical differences between the self-made orthodontic miniscrews and those from two commercial groups (p<0.05). Throughout the testing period, the quantity of ions increased from T1 to T3. After 24 h, vanadium was the first to appear on the surface in small quantities in other two commercial groups. The self-made orthodontic miniscrews exhibited no toxic effects on living cells.

Novel levan and pNIPA temperature sensitive hydrogels for 5-ASA controlled release

Levan based cross-linker was successfully synthesized and used to prepare a series of more biocompatible and temperature responsive levan/N-isopropyl acrylamide (levan/pNIPA) hydrogels by redox polymerization at room temperature. Volume phase transition temperature (VPTT) of the hydrogels were precisely determined by derivative differential scanning calorimetry (DDSC). Incorporation of levan into the pNIPA hydrogel increased the VPTT from 32.8°C to 35.09°C, approaching to body temperature. Swelling behavior and 5-aminosalicylic acid (5-ASA) release of the hydrogels were found to vary significantly with temperature and composition. Moreover, a remarkable increase in thermal stability of levan within hydrogel with increase of pNIPA content was recorded. The biocompatibility of the hydrogels were tested against mouse fibroblast L929 cell line in phosphate buffer saline (PBS, pH 7.4). The hydrogels showed increasing biocompatibility with increasing levan ratio, indicating levan enhanced the hydrogel surface during swelling.

X-ray shielding polyurethanes: Synthesis and characterization

ABSTRACTSynthesis and characterization of X-ray shielding thermoplastic polyurethane elastomers which are capable of blocking harmful radiation emitted by various sources are reported. X-ray shielding capability was generated in the polymer by covalently binding iodine atoms in a monomer and polymerizing it with other monomers such that the resultant polymer has the capability of shielding X-radiation. For rendering X-ray shielding capability to the polyurethane, Bisphenol-A (BPA) was iodinated to 4,4′-isopropylidinedi-(2,6-diiodophenol) (IBPA) and it was used as a chain extender during the synthesis of polyurethane. Polyurethanes were synthesized by reacting 1,6-diisocyanatohexane and IBPA with two different polyols, namely, poly(tetramethylene glycol) and poly(hexamethylene carbonate) diol. X-ray shielding polyurethanes (XPU) were characterized by infrared spectroscopy, thermogravimetry, dynamic mechanical analysis, energy-dispersive X-ray analysis, gel permeation chromatography, and X-radiography. Studies showed that by effectively changing polyol from polyether to polycarbonate, XPUs having different physicomechanical properties could be manufactured. Furthermore, these polyurethanes were also found to be noncytotoxic to L929 fibroblast cell lines. X-ray images revealed that the incorporation of IBPA has rendered X-ray opacity to the polyurethanes which are several times higher than the aluminum wedge of equivalent thickness. The materials are sufficiently flexible and rubbery, so can be used as coatings, films, or sheets for applications in energy sector, power-generating nuclear power plants, defense sector (bunkers for army personnel), medical applications (X-ray diagnostic and CT scanner rooms, gamma radiation therapy of cancer), etc.

An in vitro ethnopharmacological study on Prangos ferulacea: a wound healing agent.

Introduction: Traditionally Prangos ferulacea root is being used as an effective wound healing agent especially for pus-filled wounds both in human and stocks in the western north of Iran. Regarding the subject we decided to study P. ferulacea roots essential oil (PFE) for its antimicrobial and wound healing activities. Methods: The in vitro wound healing activity of PFE was evaluated in the mouse fibroblast cell line L929 using MTT assay of cell viability and cytotoxicity indices. Scratch assay as an in vitro model of wound healing assay was also conducted in this study. Moreover, the type I collagen content was used as an indicator of progress in wound healing process using Sircol collagen assay. Besides, PFE was subjected to GC/MS to identify the chemical constituents, and antimicrobical property was also evaluated against S. aureus, S. epidermidis, E. coli, P. aeruginosa, S. paratyphi and C. albicans using agar dilution method. Results: GC/MS analysis showed that the monoterpene hydrocarbones dominated in PFE, amounting to a total percentage of 95.1% with the major constituents: β-Phellandrene (32.1%), m-Tolualdehyde (26.2%), and δ-3-carene (25.8%). PFE inhibited the growth of S. aureus and P. aeruginusa with the MIC value of 20 µg/mL. In addition, at the second day of treatment, PFE at concentrations of 4 and 16 µg/mL significantly (P<0.001) enhanced the migration rate of L929 cells by 87.05±2.4 and 63.5±0.08 %, respectively. Moreover, the collagen production by L929 cells was increased greatly (P<0.001). Conclusion: It is proposed that the excellent antimicrobial activity along with the significant increase of migration rate and collagen production by fibroblast cells might be associated with the high content and synergistic effect of the monoterpens, corroborating the traditional usage of this plant as a wound healing agent.

Evaluation of cytotoxicity of 5-n-alkylresorcinol homologs and fraction on mouse fibroblast cell line L929

Cytotoxic effect of natural 5-n-alkylresorcinol fraction, individual homologs and some related compounds (resorcinol, orcinol and olivetol) was tested in vitro against mouse fibroblast cell line L929 in terms of their safety for use according to PN-EN ISO 10993-5:2009 method. Alkylresorcinol-rich fraction and five known individual alkylresorcinol homologs (C17:0, C19:0 C21:0, C23:0 and C25:0) were obtained from spelt (Triticum spelta L.) bran. The structures of these compounds were elucidated and confirmed by using two spectroscopic techniques: MS and NMR. Hydroquinone, positional isomer of resorcinol, was used as cytotoxic positive control. Cytotoxicity was expressed as IC50 and was estimated in the range of 171–2142 µM for individual homologs depending on alkyl chain length. Alkylresorcinol-rich fraction, individual homologs, orcinol and olivetol exhibited cytotoxicity lower than hydroquinone but higher than resorcinol on normal cells. The highest cytotoxicity among isolated compounds was evaluated for C17:0. Structure–activity relationship was dose dependent and can be described by quadratic function. This study extends our knowledge about potential safety of use of alkylresorcinols in diet supplements, cosmetics or pharmaceutical products.

Physicochemical, antioxidant and biocompatible properties of chondroitin sulphate isolated from chicken keel bone for potential biomedical applications

Chicken keel bone cartilage was explored for cheaper and sustainable source for isolation of chondroitin sulphate (CS) for its future use in tissue engineering and pharmaceutical industry. HPSEC analysis displayed two peaks of 100kDa for CS-keel polysaccharide and 1kDa for protein. DLS analysis of CS-keel displayed polydispersity. CS-keel yield was 15% and 53±5% uronic acid content. The quantified percentages of UA-GalNAc4S and UA-GalNAc6S disaccharide in CS-keel were 58% and 42%, respectively. FT-IR identified CS-keel to be chondroitin 4-sulphate. 1H NMR of CS-keel confirmed the presence of N-acetylgalactosamine and Glucuronic acid. FESEM demonstrated layer structure and AFM displayed the size of CS-keel fibres. DSC, TGA and DTG studies of CS-keel showed Td at 243°C. In vitro cell proliferation assay and morphological analysis of mouse fibroblast L929 cell lines confirmed the biocompatibility of CS-keel. CS-keel (5mg/ml) exhibited ∼49% antioxidant activity against DPPH and 22% against superoxide radical protecting from oxidative damage. CS-keel demonstrated better (70.3%) emulsifying activity than commercial sodium alginate (60.2%).

Actividad antibacteriana, degradación hidrolítica y microbiana y citotoxicidad in vitro de poliuretanos sintetizados con polioles derivados del aceite de higuerilla

Biological activities from polyurethanes (PUs) synthesized from polyols (derived from castor oil) and isophorone diisocyanate were evaluated. In vitro degradability was evaluated by phosphate buffered saline (PBS) and antibacterial degradation with Escherichia coli and Pseudomonas aeruginosa. The biocompatibility was analyzed by: i) the antimicrobial activity against E. coli, S. aureus and P. aeruginosa, and ii) in vitro cytotoxicity assays using mouse embryonic fibroblast cell line L-929 in direct contact with the PUs and with NIH/3T3 cells in indirect contact with the PUs degradation products. PUs with polyol P1 (2,64% molar relation of pentaerythritol and castor oil) was the material with better biodegradation properties: 1.125±0.110% in 72 h by PBS at 100 oC. In general, all materials were degraded up to 1.000±0.223% and 2.251±0.010% in 72 h by E. coli and P. aeruginosa, respectively. On the other hand, it was determined a close relationship between functionality of polyol and bacterial inhibition. The antibacterial effect of the PUs decreased by 67% for E. coli, 55% for S. aureus and 56% for P. aeruginosa after 24 h. Chemical modification of castor oil did not generate a cytotoxic effect on the tested cell lines. The evaluated materials are suggested as candidates to obtain biomaterials due to their mechanical properties and biocompatibility presented in untransformed cells.

Truncatones A–D, benzo[j]fluoranthenes from Annulohypoxylon species (Xylariaceae, Ascomycota)

From stromata (fruiting bodies) of three xylariaceous fungi belonging to the genus Annulohypoxylon (A. leptascum, A. cf. truncatum and an unidentified Annulohypoxylon sp.), truncatone A (1), three unprecedented derivatives named truncatones B–D (2–4) besides the known 4,5,4′,5′-tetrahydroxy-1,1′-binaphthyl (BNT, 5), hypoxylonol C (6) and hypoxylonol F (7) were isolated. Planar structures of the new benzo[j]fluoranthene derivatives 2–4 were determined on the basis of NMR and HRESIMS data. While the relative configuration of 4 was demonstrated by ROESY NMR data and 1H,1H coupling constants, absolute configurations of 1, 2, 4 were determined by CD spectroscopy. Compounds 1, 3 and 4 exhibited cytotoxicity against the mouse fibroblast cell line L929.

In Vitro and In Vivo Toxicity Evaluation of Colloidal Silver Nanoparticles Used in Endodontic Treatments

IntroductionSilver nanoparticles have been used for different purposes in dentistry, including endodontic treatments. The aim of this study was to determine the cytotoxicity of different types of silver nanoparticles on mouse fibroblast cell line L929 and the reaction of subcutaneous connective tissue of Wistar rats to these nanoparticles. MethodsSilver nanoparticles of an average size of 5 nm were synthesized with ammonia (SNA) or polyvinylpyrrolidone (SNP). L929 was exposed to SNA and SNP (0.1–100 μg/mL), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and enzyme-linked immunosorbent assays were performed after 6, 24, and 48 hours. Culture medium was used as the control. Sixteen rats received, individually, 3 polyethylene tubes filled with a fibrin sponge embedded in 100 μL SNA or SNP (1 μg/mL). A fibrin sponge with no embedding was the control. Tissue reaction was performed qualitatively and quantitatively after 7, 15, 30, and 90 days of implantation in the dorsal connective tissue of Wistar rats. ResultsSNA and SNP were cytotoxic to L929 in higher concentrations, with SNA significantly more toxic than SNP. SNA and SNP did not induce significant interleukin-1β and interleukin-6 production. The release of stem cell factor by L929 increased 48 hours after the treatment with SNP at 5 μg/mL. Histologic examination showed that the inflammatory responses caused by SNA and SNP at 1 μg/mL were similar to the control in all experimental periods. ConclusionsIt was concluded that SNA and SNP were not cytotoxic at 25 μg/mL or lower concentrations. However, for safe clinical use, further studies establishing others points of its toxicologic profile are recommended.