The effect of cryoprotectant on kangaroo sperm ultrastructure and mitochondrial function.

PubMed

McClean, Rhett; Holt, William V; Zee, Yeng Peng; Lisle, Allan; Johnston, Stephen D

2008-12-01

This study examined the effect of cryoprotectants (20% DMSO, a 10% DMSO/10% glycerol mixture, 20% glycerol and 1M sucrose solution) on kangaroo sperm structure and function, along with the effect of varying concentrations of glycerol on sperm mitochondrial function. Eastern grey kangaroo cauda epididymidal spermatozoa were incubated for 10 min at 35 degrees C in each cryoprotectant and the plasma membrane integrity (PMI) and motility assessed using light microscopy. The same samples were fixed for TEM and the ultrastructural integrity of the spermatozoa examined. To investigate the effect of glycerol on the kangaroo sperm mitochondrial function, epididymidal spermatozoa were incubated with JC-1 in Tris-citrate media at 35 degrees C for 20 min in a range of glycerol concentrations (0%, 5%, 10%, 15% and 20%) and the mitochondrial membrane potential (MMP) and plasma membrane integrity determined. As expected, incubation of spermatozoa in 20% glycerol for 10 min resulted in a significant reduction in motility, PMI and ultrastructural integrity. Interestingly, incubation in 20% DMSO resulted in no significant reduction in motility or PMI but a significant loss of structural integrity when compared to the control spermatozoa (0% cryoprotectant). However, 20% DMSO was overall less damaging to sperm ultrastructure than glycerol, a combination of 10% glycerol and 10% DMSO, and sucrose. While all glycerol concentrations had an adverse effect on mitochondrial function, the statistical models presented for the relationship between MMP and glycerol predicted that spermatozoa, when added to 20% glycerol, would lose half of their initial MMP immediately at 35 degrees C and MMP would halve after 19.4 min at 4 degrees C. Models for the relationship between PMI and glycerol predicted that spermatozoa would lose half of their initial PMI after 1.8 min at 35 degrees C and PMI would halve after 21.1 min at 4 degrees C. These results suggest that if glycerol is to be used as a

Antimicrobial and cytotoxic effects of Mexican medicinal plants.

PubMed

Jacobo-Salcedo, Maria del Rosario; Alonso-Castro, Angel Josabad; Salazar-Olivo, Luis A; Carranza-Alvarez, Candy; González-Espíndola, Luis Angel; Domínguez, Fabiola; Maciel-Torres, Sandra Patricia; García-Lujan, Concepción; González-Martínez, Marisela del Rocio; Gómez-Sánchez, Maricela; Estrada-Castillón, Eduardo; Zapata-Bustos, Rocio; Medellin-Milán, Pedro; García-Carrancá, Alejandro

2011-12-01

The antimicrobial effects of the Mexican medicinal plants Guazuma ulmifolia, Justicia spicigera, Opuntia joconostle, O. leucotricha, Parkinsonia aculeata, Phoradendron longifolium, P. serotinum, Psittacanthus calyculatus, Tecoma stans and Teucrium cubense were tested against several human multi-drug resistant pathogens, including three Gram (+) and five Gram (-) bacterial species and three fungal species using the disk-diffusion assay. The cytotoxicity of plant extracts on human cancer cell lines and human normal non-cancerous cells was also evaluated using the MTT assay. Phoradendron longifolium, Teucrium cubense, Opuntia joconostle, Tecoma stans and Guazuma ulmifolia showed potent antimicrobial effects against at least one multidrug-resistant microorganism (inhibition zone > 15 mm). Only Justicia spicigera and Phoradendron serotinum extracts exerted active cytotoxic effects on human breast cancer cells (IC50 < or = 30 microg/mL). The results showed that Guazuma ulmifolia produced potent antimicrobial effects against Candida albicans and Acinetobacter lwoffii, whereas Justicia spicigera and Phoradendron serotinum exerted the highest toxic effects on MCF-7 and HeLa, respectively, which are human cancer cell lines. These three plant species may be important sources of antimicrobial and cytotoxic agents.

Ultrastructural and some functional changes in tumor cells treated with stabilized iron oxide nanoparticles.

PubMed

Yurchenko, O V; Todor, I N; Khayetsky, I K; Tregubova, N A; Lukianova, N Yu; Chekhun, V F

2010-12-01

To study the ultrastructure and some functional indexes of tumor cells treated with stabilized iron nanoparticles in vitro. 3-[4,5dimethylthiazol-2-1]-2,5-diphenyltetrazolium bromide (MTT)-test, electron microscopy, polarography with applying of closed Clark's electrode. It was shown that cultivation of cells with stabilized Fe(3)O(4) leads to intracellular accumulation of ferromagnetic nanoparticles. The most active ferromagnetic uptake by cells has been observed after 24 and 48 h of incubation. The presence of ferromagnetic in cells led to altered mitochondrial structure that caused the decrease of oxygen uptake rate in the cells of all studied lines. Ferromagnetic released from the majority of cells via exocytosis or clasmacytosis after a certain period of time. The number of dead cells or cells with severe damage was moderate, so cytotoxic action of stabilized iron oxide nanoparticles was minimal toward the studied cell lines. the presence of ferromagnetic nanoparticles in culture medium led to alterations in mitochondria ultrastructural organization and decrease of oxygen uptake by mitochondria in sensitive and anticancer-drugs resistant cells.

Marine bivalve shell geochemistry and ultrastructure from modern low pH environments: environmental effect versus experimental bias

NASA Astrophysics Data System (ADS)

Hahn, S.; Rodolfo-Metalpa, R.; Griesshaber, E.; Schmahl, W. W.; Buhl, D.; Hall-Spencer, J. M.; Baggini, C.; Fehr, K. T.; Immenhauser, A.

2012-05-01

Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy) were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island. Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

Effects of chlorpyrifos on the growth and ultrastructure of green algae, Ankistrodesmus gracilis.

PubMed

Asselborn, Viviana; Fernández, Carolina; Zalocar, Yolanda; Parodi, Elisa R

2015-10-01

The effect of the organophosphorus insecticide chlorpyrifos on the growth, biovolume, and ultrastructure of the green microalga Ankistrodesmus gracilis was evaluated. Concentrations of 9.37, 18.75, 37.5, 75 and 150mgL(-1) of chlorpyrifos were assayed along with a control culture. At the end of the bioassay the ultrastructure of algal cells from control culture and from cultures exposed to 37.5 and 150mgL(-1) was observed under transmission (TEM) and scanning electron microscopy (SEM). After 24 and 48h, treatments with 75 and 150mgL(-1) inhibited the growth of A. gracilis; whereas after 72 and 96h, all the treatments except at 9.37mgL(-1) significantly affected the algae growth. The effective concentration 50 (EC50) after 96h was 22.44mgL(-1) of chlorpyrifos. After the exposure to the insecticide, an increase in the biovolume was observed, with a larger increase in cells exposed to 75 and 150mgL(-1). Radical changes were observed in the ultrastructure of cells exposed to chlorpyrifos. The insecticide affected the cell shape and the distribution of the crests in the wall. At 37.5mgL(-1) electodense bodies were observed along with an increase in the size and number of starch granules. At 150mgL(-1) such bodies occupied almost the whole cytoplasm together with lipids and remains of thylakoids. Autospores formation occurred normally at 37.5mgL(-1) while at 150mgL(-1) karyokinesis occurred, but cell-separation-phase was inhibited. The present study demonstrates that the exposure of phytoplankton to the insecticide chlorpyrifos leads to effects observed at both cellular and population level. Copyright © 2015 Elsevier Inc. All rights reserved.

[Effects of infrasound therapy on proliferation, apoptosis and ultrastructure of human B lymphoma Raji cells].

PubMed

Bao, Yong; Fan, Jian-Zhong; Li, Ke; Li, Chuan; Yang, Jun-Feng

2008-06-01

To investigate the effect of infrasound therapy on the proliferation, apoptosis and ultrastructure of human B lymphoma Raji cells. Human B lymphoma Raji cells were exposed to infrasound treatment for 15, 30, 60, 90 and 120 min and cultured subsequently for 24 or 48 h. MTT assay, flow cytometry analysis, and electron microscopy were performed to examine the proliferative status, cell apoptosis and ultrastructural changes of the exposed cells, respectively. MTT assay revealed no significant changes in the proliferation of the cells exposed to infrasound treatment (P>0.05), nor did flow cytometry analysis identified significant variation in the cell apoptosis (P>0.05). Scanning electron microscopy, however, identified shortened or reduced cell processes and microvilli on the surface of the cells with infrasound exposure and a subsequent 24-hour culture, and the cell membrane surface became smooth. Under transmission electron microscope, the cells with infrasound treatment presented with significantly reduced microvilli, and the cell nuclei appeared homogeneous, with cytoplasmic budding and losses after a 48-hour culture. Infrasound less than 90 dB does not obviously affect the proliferation and apoptosis of Raji cells, but may directly cause cell ultrastructural changes such as reduction of the cell processes.

Ultrastructural findings in noncompaction prevail with neuromuscular disorders.

PubMed

Finsterer, Josef; Stöllberger, Claudia

2013-01-01

Little is known about the ultrastructural abnormalities of left ventricular hypertrabeculation/noncompaction (LVHT). This literature review aimed to summarize and discuss ultrastructural abnormalities described in LVHT so far. The literature search was conducted via MEDLINE using the search terms 'non-compaction', 'noncompaction', 'left ventricular hypertrabeculation', 'spongy myocardium' in combination with the terms 'ultra-structural', or 'electron microscopy'. Altogether, 11 studies reporting ultrastructural investigations of LVHT were retrieved. In these 11 studies, data on 13 patients with LVHT were presented. Ultrastructural abnormalities found in these study patients were generally nonspecific and included an increase in the number of mitochondria (n = 3), abnormally shaped mitochondria (n = 2), distorted cristae (n = 3), sarcomeric derangement (n = 3), immature cardiomyocytes (n = 1), lipid-like inclusions (n = 1), enlarged interstitial spaces (n = 1), increased interstitial collagen (n = 1), or increased glycogen (n = 1). The morphological abnormalities were most prominent in patients with a neuromuscular disorder like Barth syndrome or mitochondrial myopathy. Only in few patients with LVHT, ultrastructural investigations have been performed so far. Ultrastructural abnormalities in LVHT are nonspecific and most prominent in patients with a neuromuscular disorder. There is a strong need to carry out thorough ultrastructural investigations of LVHT to contribute to the understanding of this still unexplained myocardial abnormality.

Anti-inflammatory, gastroprotective, and cytotoxic effects of Sideritis scardica extracts.

PubMed

Tadić, Vanja M; Jeremic, Ivica; Dobric, Silva; Isakovic, Aleksandra; Markovic, Ivanka; Trajkovic, Vladimir; Bojovic, Dragica; Arsic, Ivana

2012-03-01

Sideritis scardica Griseb. (ironwort, mountain tea), an endemic plant of the Balkan Peninsula, has been used in traditional medicine in the treatment of gastrointestinal complaints, inflammation, and rheumatic disorders. This study aimed to evaluate its gastroprotective and anti-inflammatory activities. Besides, continuously increasing interest in assessing the role of the plant active constituents preventing the risk of cancer was a reason to make a detailed examination of the investigated ethanol, diethyl ether, ethyl acetate, and N-butanol extracts regarding cytotoxicity. Oral administration of the investigated extracts caused a dose-dependent anti-inflammatory effect in a model of carrageenan-induced rat paw edema. Gastroprotective activity of the extracts was investigated using an ethanol-induced acute stress ulcer in rats. The cytotoxic activity of plant extracts was assessed on PBMC, B16, and HL-60 cells and compared to the cytotoxicity of phenolic compounds identified in extracts. Apoptotic and necrotic cell death were analyzed by double staining with fluoresceinisothiocyanate (FITC)-conjugated annexin V and PI. The developed HPLC method enabled qualitative fingerprint analysis of phenolic compounds in the investigated extracts. Compared to the effect of the positive control, the anti-inflammatory drug indomethacine (4 mg/kg), which produced a 50 % decrease in inflammation, diethyl ether and N-butanol extracts exhibited about the same effect in doses of 200 and 100 mg/kg (53.6 and 48.7 %; 48.4 and 49.9 %, respectively). All investigated extracts produced dose-dependent gastroprotective activity with the efficacy comparable to that of the reference drug ranitidine. The diethyl ether extract showed significant dose-dependent cytotoxicity on B16 cells and HL-60 cells, decreasing cell growth to 51.3 % and 77.5 % of control, respectively, when used at 100 µg/mL. It seems that phenolic compounds (apigenin, luteolin, and their corresponding glycosides) are

Effects of growth hormone on the ultrastructure of bovine preimplantation embryos.

PubMed

Kölle, Sabine; Stojkovic, Miodrag; Reese, Sven; Reichenbach, Horst-Dieter; Wolf, Eckhard; Sinowatz, Fred

2004-07-01

Growth hormone (GH) has recently been shown to promote the development of preimplantation embryos. The aim of our study was therefore to analyze the effects of GH on the morphology and ultrastructure of the cells of bovine preimplantation embryos produced by in vitro fertilization (IVF). In order to determine the physiologically optimal morphology of blastocysts, ex vivo embryos obtained by uterine flushing were also included in the study. As shown by transmission electron microscopy, treatment with GH induced the elimination of glycogen storage in cells of the inner cell mass of 7-day-old embryos. GH also stimulated the exocytosis of lipid vesicles in the inner cell mass and trophectoderm cells of these embryos. Quantitative analysis of micrographs demonstrated a higher volume density of embryonic mitochondria in 7-day-old embryos cultured with GH than in control embryos. Treatment with GH regularly resulted in an improvement of the ultrastructural features of embryos produced in vitro, thus resembling the morphology of ex vivo embryos. Scanning electron-microscopy studies demonstrated that GH altered the structure and the pore size of the zona pellucida of blastocysts. Our studies imply that GH can modulate carbohydrate, lipid, and energy metabolism and influence transportation processes in the early IVF embryo.

Microbicidal and cytotoxic effects of functional water in vitro.

PubMed

Gomi, Kazuhiro; Makino, Tomohiko; Suzuki, Shinichi; Hasegawa, Masako; Maeda, Nobuko; Arai, Takashi

2010-10-01

Several kinds of functional water are used in the fields of food hygiene and medicine. The purpose of this study was to evaluate both the disinfection and cytotoxic effects of functional water in comparison with commonly used root canal irrigants such as sodium hypochlorite solution and hydrogen peroxide solution. Three kinds of functional water were examined: alkaline electrolysis water (AEW), strong acid electrolyzed water (SAEW), and hypochlorous acid water (HAW). The disinfection effect was studied using Enterococcus faecalis and Candida albicans with or without organic substance. Each kind of functional water was applied to samples, and the colony formation was evaluated. The cytotoxic effect was evaluated by mitogenic assay (MTT) and alkaline phosphatase (ALPase) activity in pulp cells. SAEW and HAW showed microbicidal effects in the presence of organic substance, with an effect almost similar to sodium hypochlorite solution. AEW did not show any microbicidal effect. SAEW, AEW, and HAW at 10- and 1,000-times dilution did not inhibit the MTT assay and ALPase activity. The cytotoxicity of SAEW and HAW against pulp cells was mild compared to that of sodium hypochlorite solution. Functional water like SAEW and HAW have a good microbicidal effect under existing organic substance and are also mild to pulp cells.

Heavy metal-induced cytotoxicity to cultured human epidermal keratinocytes and effects of antioxidants.

PubMed

Kappus, H; Reinhold, C

1994-04-01

Human epidermal keratinocytes which have been cultured were treated with the heavy metal ions of cadmium, mercury, copper and zinc. Cytotoxicity was measured either by protein estimation or by using the neutral red assay. Antioxidants were added in order to find out whether heavy metal-induced cytotoxicity is related to oxidative stress. All metals used showed considerable cytotoxic effects within 24 h in moderate concentrations. None of the antioxidants vitamin E (alpha-tocopherol), pyrogallol, propyl gallate, BHT or ebselen showed any protective or preventive effect. This indicates that oxidative stress may not be involved in the cytotoxicity induced by heavy metals in human epidermal keratinocytes. The cells used are, however, a valuable tool to study mechanisms of cytotoxicity.

Effects of ultraviolet radiation and temperature on the ultrastructure of zoospores of the brown macroalga Laminaria hyperborea.

PubMed

Steinhoff, F S; Wiencke, C; Müller, R; Bischof, K

2008-05-01

The interactive effects of an 8 h exposure to UV radiation and altered temperatures on the ultrastructure and germination of zoospores of the sublittoral brown alga Laminaria hyperborea (Gunn.) Foslie were investigated for the first time. Spores were exposed to four temperatures (2, 7, 12 and 17 degrees C) and three light regimes (PAR, PAR + UV-A, PAR + UV-A+UV-B). Freshly-released spores of L. hyperborea lack a cell wall and contain a nucleus with fine granular nucleoplasm and a nucleolus, one chloroplast, several mitochondria, dictyosomes and an endoplasmatic reticulum. Further, several kinds of so-called adhesive vesicles, lipid globuli and physodes containing UV-absorbing phlorotannins are embedded in the cytoplasm. No eye-spot is present. Physodes were found but they were rare and small. After an 8 h exposure to UV-B, the nucleoplasm had a mottled structure, chloroplasts contained plastoglobuli, the structure of the mitochondria changed from crista- to sacculus-type and germination was strongly inhibited at all temperatures. UV-A only had an impact on the ultrastructure at the highest temperature tested. The strongest effects were found at 17 degrees C, where germination was reduced to 35%, 32% and 9% after exposure to PAR, PAR+UV-A and PAR + UV-A + UV-B, respectively. This study indicates that UV-B radiation has strong damaging effects on the physiology and ultrastructure of zoospores of L. hyperborea. The results are important for developing scenarios for the effect of enhanced UV radiation and increasing temperatures caused by global climate changes.

Effect of unilateral extraction of molar teeth on suprahyoid muscles: macroscopic and ultrastructural aspects.

PubMed

Iyomasa, Mamie Mizusaki; Issa, João Paulo Mardegan; Siéssere, Selma; Regalo, Simone Cecílio Hallak; Watanabe, Ii-sei

2008-12-01

Anatomical and physiologic components are parts of the stomatognathic system and their interaction results in integrated functional activities. Important alterations in the masticatory system originated by dental loss affect the bone, oral mucosa and muscular function. Dental arch structures specifically designed to receive and expose teeth allow performance of their functions. But the distinction between bony and soft tissues is lost when teeth are removed since there is not a specific function to be completed. The aim of this study was to evaluate the macroscopic and ultrastructural effects of the unilateral extraction of molar teeth on the suprahyoid muscles function, using twenty young male gerbils (Meriones unguiculatus) as the experimental animal model. They were divided in experimental malocclusion (n=10) and control (n=10) groups. The experimental malocclusion group was submitted to exodontia of the left upper molars and the control group was not submitted to this procedure and served as sham-operated. For macroscopic analysis of the suprahyoid muscle, the skin was uplifted and the muscles dissected individually and removed for weight analysis according to Scherle method. The electron microscopy analysis was made in ultra thin sections of small suprahyoid muscle fragments from the experimental and control groups, examined in a Jeol 1010, 880 Kv transmission electron microscope. Several micrographs at magnifications of 3000x, 6000x, 30,000x were randomly selected for the qualitative analysis of the muscle fiber ultrastructures. Sixty days after the induced unilateral occlusal alteration no macroscopic morphologic changes was detected in the suprahyoid muscles and the muscle volume differences between the right and left sides and between groups were not significant. However, in the ultrastructural analysis suprahyoid muscles showed characteristics of specific adaptation to the unilateral occlusal alteration, by the reduced density of subsarcolemmal

Different effects of amino acid-based and glucose-based dialysate from peritoneal dialysis patients on mesothelial cell ultrastructure and function.

PubMed

Chan, Tak-Mao; Leung, Jack Kok-Hung; Sun, Yuling; Lai, Kar-Neng; Tsang, Ryan Chi-Wai; Yung, Susan

2003-06-01

Peritoneal dialysis fluid (PDF) containing amino acids has been introduced recently aiming to improve the nutritional status of PD patients. Dextrose-based PDFs have been implicated in progressive functional and structural deterioration of the peritoneal membrane. Limited data are currently available regarding the effect of amino acid-based PDF on the function and ultrastructure of human peritoneal mesothelial cells (HPMCs), which play a critical role in peritoneal membrane pathophysiology. We investigated the effects of two commercially available PDFs, which utilized dextrose (1.5% Dianeal) or amino acids (1.1% Nutrineal) as the osmotic agent, obtained from patients after a 4 h dwell, on HPMC proliferation (MTT assay and cell counting) and viability [lactate dehydrogenase (LDH)release], interleukin-6 (IL-6) secretion (commercial enzyme-linked immunosorbent assay) and ultrastructure (scanning and transmission electron microscopy). Exposure of HPMCs to 1.5% Dianeal reduced cell proliferation, total cellular protein synthesis, IL-6 secretion and cell attachment, but prolonged the cell doubling time on recovery, and increased LDH release (P<0.001, P<0.001, P<0.0001, P<0.0001, P<0.001 and P<0.001, respectively). The 1.1% Nutrineal reduced HPMC proliferation (P<0.001) and increased IL-6 secretion (P<0.0001), but did not affect cell attachment, LDH release, protein synthesis or cell doubling time. Ultrastructural studies of HPMCs exposed to Dianeal showed cell flattening, increased cell surface area, reduced microvilli, and intracellular organelles compatible with dysfunctional mitochondria. In contrast, the ultrastructural morphology of HPMCs was relatively preserved after incubation with Nutrineal. Our results showed that HPMC ultrastructure, viability and protein synthesis were better preserved with amino acid-based PDF, compared with conventional dextrose-based PDF. The significance of IL-6 induction by Nutrineal remains to be elucidated.

Effects of vitrification on nuclear maturation, ultrastructural changes and gene expression of canine oocytes

PubMed Central

2010-01-01

Background Cryopreservation of oocytes, which is an interesting procedure to conserve female gametes, is an essential part of reproductive biotechnology. The objective of the present study was to investigate the effects of vitrification on nuclear maturation, ultrastructural changes and gene expression of canine oocytes. Methods Immature oocytes (germinal vesicles) isolated from ovaries of normal bitches (> 6 months of age) were either vitrified in open pulled straw (OPS) using 20% ethylene glycol (EG) and 20% dimethyl sulfoxide (DMSO) as vitrification solution or exposed to vitrification solution without subjected to liquid nitrogen. After warming, oocytes were investigated for nuclear maturation following in vitro maturation (IVM), ultrastructural changes using transmission electron microscopy (TEM) and gene expression using RT-PCR. Fresh immature oocytes were used as the control group. Results The rate of resumption of meiosis in vitrified-warmed oocytes (53.4%) was significantly (P < 0.05) lower than those of control (93.8%) and exposure (91.4%) groups. However, there were no statistically significant differences among groups in the rates of GV oocytes reaching the maturation stage (metaphase II, MII). The ultrastructural alterations revealed by TEM showed that cortical granules, mitochondria, lipid droplets and smooth endoplasmic reticulum (SER) were affected by vitrification procedures. RT-PCR analysis for gene expression revealed no differences in HSP70, Dnmt1, SOD1 and BAX genes among groups, whereas Bcl2 was strongly expressed in vitrified-warmed group when compared to the control. Conclusion Immature canine oocytes were successfully cryopreserved, resumed meiosis and developed to the MII stage. The information obtained in this study is crucial for the development of an effective method to cryopreserve canine oocytes for establishment of genetic banks of endangered canid species. PMID:20565987

Ultrastructural Effects of Bacillus thuringiensis var. san diego on Midgut Cells of the Cottonwood Leaf Beetle1

Treesearch

Leah S. Bauer; Stuart H. Pankratz

1992-01-01

Sequential observations of the ultrastructural effects of Bacillus thuringiensis var. san diego were made on midgut epithelial cells of the cottonwood leaf beetle, Chrysomela scripta F. Larvae imbibed a droplet of B. thuringiensis var. san diego containing endotoxin and live...

Paraquat-induced ultrastructural changes and DNA damage in the nervous system is mediated via oxidative-stress-induced cytotoxicity in Drosophila melanogaster.

PubMed

Mehdi, Syed Hassan; Qamar, Ayesha

2013-08-01

Paraquat (PQ), a quaternary nitrogen herbicide, is commonly used as a pesticide despite of its high toxicity. Our study evaluated the effect of subchronic PQ exposure on the neuropathology, genotoxicity, and antioxidant activity on the nervous tissue of Drosophila melanogaster. We also explored the behavioral effect of PQ on D. melanogaster. Furthermore, we attempted to validate the mechanism by evaluating PQ-induced cytotoxicity on the D-Mel2 cell lines. The fruit fly D. melanogaster serves as a feasible model to understand the mechanism of neurodegenerative diseases. Our study shows a dose-dependent PQ-induced neuropathology in the brain tissue of D. melanogaster as evidenced by hematoxylin and eosin staining, silver nitrate staining, and transmission electron microscopy. Electron microscopic study of D. melanogaster brain tissue exhibited vacuolar degeneration and significant neuronal damage across the nervous tissue structure in comparison with control. Our findings also indicate a dose-dependent locomotor impairment and decreased superoxide dismutase (SOD) specific activity in PQ-treated D. melanogaster. These PQ-induced neuroanatomical changes and decreased SOD specific activity showed a significant association with oxidative DNA damage as observed by alkaline comet assay. Additionally, we show, for the first time, a dose-dependent PQ-induced cytotoxicity in the D-Mel2 cells suggesting loss of neuronal cell viability via cytotoxic damage. Our data suggest that PQ exposure results in neurodegeneration in D. melanogaster and that fruit fly is a suitable in vivo model for correlating the neuroanatomical changes with neurotoxic damages to nervous system.

Anti-inflammatory and ultrastructural effects of Turkish propolis in a rat model of endotoxin-induced uveitis.

PubMed

Ertürküner, Salime Pelin; Yaprak Saraç, Elif; Göçmez, Semil Selcen; Ekmekçi, Hakan; Öztürk, Zeynep Banu; Seçkin, İsmail; Sever, Özkan; Keskinbora, Kadircan

2016-01-01

Experimental animal models of acute uveitis, an inflammatory eye disease, can be established via endotoxin-induced inflammation. Propolis, a natural substance collected by honeybees from buds and tree exudates, has antioxidant, antibacterial, antiviral, and anti-inflammatory effects. We investigated the effects of propolis, obtained from the Sakarya province of Turkey, on endotoxin-induced uveitis using immunohistochemical, ultrastructural, and biochemical approaches. Male Wistar albino rats (n = 6/group) received intraperitoneal (ip) lipopolysaccharide (LPS) endotoxin (150 μg/kg) followed by aqueous extract of propolis (50 mg/kg ip) or vehicle; two additional groups received either saline (control) or propolis only. After 24 h, aqueous humor (AH) was collected from both eyes of each animal for analysis of tumor necrosis factor-α (TNF-α) and hypoxia-inducible factor-1α (HIF-1α). Right eyeballs were paraffin-embedded for immunohistochemical staining of nuclear factor κB (NF-κB)/p65 and left eyeballs were araldite-embedded for ultrastructural analysis. Treatment of LPS-induced uveitis with propolis significantly reduced ciliary body NF-κB/p65 immunoreactivity and AH levels of HIF-1α and TNF-α. Ultrastructural analysis showed fewer vacuoles and reduced mitochondrial degeneration in the retinal pigment epithelium, as compared to the uveitis group. The intercellular spaces of the inner nuclear layer and outer limiting membrane were comparable with those of the control group; no polymorphonuclear cells or stasis was observed in intravascular or extravascular spaces. This is the first report demonstrating an anti-inflammatory effect of Turkish propolis in a rat model of LPS-induced acute uveitis, suggesting a therapeutic potential of propolis for the treatment of inflammatory ophthalmic diseases.

Effect of citral on the cytotoxicity of doxorubicin in human B-lymphoma cells.

PubMed

Dangkong, Darinee; Limpanasithikul, Wacharee

2015-02-01

Doxorubicin is a chemotherapy agent used in non-Hodgkin's lymphoma but side effects limit its use. Citral is a mixture of neral and geranial found in essential oils of lemon grass. We evaluated the activity of citral, doxorubicin, and combination on cytotoxicity, apoptosis, and anti-proliferative effects using human lymphoma Ramos cells. Cells were treated with doxorubicin alone or in combination with citral (10, 20, and 40 μM). Cytotoxic and apoptosis studies were done after 24 and 18 h incubations, respectively. Cytotoxic effects of citral on normal human peripheral blood mononuclear cells (PBMCs) were also investigated for its safety. Changes in the expression of BCL-2 family genes were analyzed by quantitative RT-PCR. Citral had cytotoxicity on cells with an IC50 value of 77.19 ± 4.95 µM. Citral at concentrations of 10, 20, and 40 µM additively increased the cytotoxic and apoptotic effects of doxorubicin, leading to decreased IC50 (µM) of the drug from 2.50 ± 0.01 to 2.16 ± 0.03, 1.90 ± 0.04, and 1.23 ± 0.04, respectively. Enhanced cytotoxicity was not observed in normal human PBMCs. Citral (40 µM) in combination with doxorubicin (1.5 µM) increased the expression of pro-apoptotic protein BAK but significantly decreased the expression of anti-apoptotic protein BCL-XL to 5.26-fold compared with doxorubicin-treated cells. It did not change the anti-proliferative activity of drug. Citral potentiated cytotoxicity of doxorubicin by increasing apoptotic effects. We conclude that citral may have beneficial effects in patients with B cell lymphoma treated with chemotherapy.

Effect of the Insecticide Dinotefuran on the Ultrastructure of the Flight Muscle of Female Sogatella furcifera (Hemiptera: Delphacidae).

PubMed

Liu, M G; Jiang, C X; Mao, M; Liu, C; Li, Q; Wang, X G; Yang, Q F; Wang, H J

2017-04-01

Sogatella furcifera Horváth (Hemiptera: Delphacidae), is a major migratory pest of rice crops in Asia. The ultrastructure of the flight muscle directly affects the flight ability of insects. The ultrastructure of the flight muscle of some insects can be affected by insecticides. However, the ultrastructure of the flight muscle of S. furcifera and the effect of insecticides on the flight muscle of S. furcifera are not well understood. The present study was conducted to determine the effect of the insecticide dinotefuran on the ultrastructure of the flight muscle of S. furcifera females. In this study, the cross-sectional area and the diameter of the myofibril cross-sections of dinotefuran-treated S. furcifera females increased with the number of days after emergence (DAE), and they were higher than in untreated females. The sarcomere length of myofibrils increased with the number of DAE, and it differed from that of the untreated females. On the first day after emergence, the higher the concentration of dinotefuran, the smaller was the extent of decrease. On the third day after emergence, the higher the concentration of dinotefuran, the larger was the extent of enhancement. For the percentage of mitochondria, those of LC10 and LC20 dinotefuran-treated S. furcifera females increased with the number of DAE and were higher than in untreated females. LC10 dinotefuran-treated S. furcifera females exhibited the largest increase. Thus, our results suggest that the flight ability of S. furcifera increased with time. Some concentrations of dinotefuran can enhance the flight capacity of S. furcifera. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effects of management in gestational diabetes mellitus with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures: a prospective cohort study.

PubMed

Han, Yun; Zheng, Yan-Li; Wu, Ai-Min; Liu, Hong-Bin; Su, Jian-Bin; Lu, Xiao-Yan; Han, Yu-Wen; Ji, Jin-Long; Ji, Ju-Hua; Shi, Yue

2016-12-01

A great quantity of gestational diabetes mellitus with normal prepregnancy body mass index have emerged with the new criteria of gestational diabetes mellitus in China based on the International Diabetes in Pregnancy Consensus group criteria, and understanding placental changes and how they affect outcomes are necessary in order to develop effective management approach. The aim of this study was to prospectively explore the effect of active management starting from the late second trimester in gestational diabetes mellitus women with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures, and to provide scientific evidences for optimizing the management of gestational diabetes mellitus in China. Gestational diabetes mellitus women with normal prepregnancy body mass index in the same period of this prospective cohort study were divided into intervention group (n = 51) and control group (n = 55). The intervention group was managed rigorously, while the control group received conventional prenatal cares. The glucose profile, gestational weight gain and pregnancy outcomes were followed up and placental ultrastructures were observed and recorded by transmission electron microscopy. The blood glucose level and gestational weight gain in intervention group were significantly better controlled than those in control group (P < 0.01). The incidences of fetal distress, cesarean section and large for gestational age were significantly lower in intervention group than in control group (P < 0.05). There was a significant reduction in the incidence of abnormal placental ultrastructure in the intervention group (P < 0.01). After adjustment for confounding factors, the undesirable glycemic control and conventional management were related to abnormal placental ultrastructure (P < 0.05). Meanwhile, the undesirable glycemic control, abnormal placental ultrastructure and conventional management made sense in the incidence of

Aerodynamics and pollen ultrastructure in Ephedra.

PubMed

Bolinder, Kristina; Niklas, Karl J; Rydin, Catarina

2015-03-01

• Pollen dispersal is affected by the terminal settling velocity (Ut) of the grains, which is determined by their size, bulk density, and by atmospheric conditions. The likelihood that wind-dispersed pollen is captured by ovulate organs is influenced by the aerodynamic environment created around and by ovulate organs. We investigated pollen ultrastructure and Ut of Ephedra foeminea (purported to be entomophilous), and simulated the capture efficiency of its ovules. Results were compared with those from previously studied anemophilous Ephedra species.• Ut was determined using stroboscopic photography of pollen in free fall. The acceleration field around an "average" ovule was calculated, and inflight behavior of pollen grains was predicted using computer simulations. Pollen morphology and ultrastructure were investigated using SEM and STEM.• Pollen wall ultrastructure was correlated with Ut in Ephedra. The relative proportion and amount of granules in the infratectum determine pollen bulk densities, and (together with overall size) determine Ut and thus dispersal capability. Computer simulations failed to reveal any functional traits favoring anemophilous pollen capture in E. foeminea.• The fast Ut and dense ultrastructure of E. foeminea pollen are consistent with functional traits that distinguish entomophilous species from anemophilous species. In anemophilous Ephedra species, ovulate organs create an aerodynamic microenvironment that directs airborne pollen to the pollination drops. In E. foeminea, no such microenvironment is created. Ephedroid palynomorphs from the Cretaceous share the ultrastructural characteristics of E. foeminea, and at least some may, therefore, have been produced by insect-pollinated plants. © 2015 Botanical Society of America, Inc.

Ultrastructural researches on rabbit myxomatosis. Lymphnodal lesions.

PubMed

Marcato, P S; Simoni, P

1977-07-01

Ultrastructural examination of head and neck lymph nodes in rabbits with spontaneous subacute myxomatosis showed fusion of immature reticuloendothelial cells which lead to the formation of polykarocytes. There was no ultrastructural evidence of viral infection of these polykaryocytes. Histiosyncytial lymphadenitis can be considered a specific lesion of myxomatosis.

Carnosine's Effect on Amyloid Fibril Formation and Induced Cytotoxicity of Lysozyme

PubMed Central

Wu, Josephine W.; Liu, Kuan-Nan; How, Su-Chun; Chen, Wei-An; Lai, Chia-Min; Liu, Hwai-Shen; Hu, Chaur-Jong; Wang, Steven S. -S.

2013-01-01

Carnosine, a common dipeptide in mammals, has previously been shown to dissemble alpha-crystallin amyloid fibrils. To date, the dipeptide's anti-fibrillogensis effect has not been thoroughly characterized in other proteins. For a more complete understanding of carnosine's mechanism of action in amyloid fibril inhibition, we have investigated the effect of the dipeptide on lysozyme fibril formation and induced cytotoxicity in human neuroblastoma SH-SY5Y cells. Our study demonstrates a positive correlation between the concentration and inhibitory effect of carnosine against lysozyme fibril formation. Molecular docking results show carnosine's mechanism of fibrillogenesis inhibition may be initiated by binding with the aggregation-prone region of the protein. The dipeptide attenuates the amyloid fibril-induced cytotoxicity of human neuronal cells by reducing both apoptotic and necrotic cell deaths. Our study provides solid support for carnosine's amyloid fibril inhibitory property and its effect against fibril-induced cytotoxicity in SH-SY5Y cells. The additional insights gained herein may pave way to the discovery of other small molecules that may exert similar effects against amyloid fibril formation and its associated neurodegenerative diseases. PMID:24349167

Microwave-induced Apoptosis and Cytotoxicity of NK Cells through ERK1/2 Signaling.

PubMed

Zhao, Li; Li, Jing; Hao, Yan Hui; Gao, Ya Bing; Wang, Shui Ming; Zhang, Jing; Dong, Ji; Zhou, Hong Mei; Liu, Shu Chen; Peng, Rui Yun

2017-05-01

To investigate microwave-induced morphological and functional injury of natural killer (NK) cells and uncover their mechanisms. NK-92 cells were exposed to 10, 30, and 50 mW/cm2 microwaves for 5 min. Ultrastructural changes, cellular apoptosis and cell cycle regulation were detected at 1 h and 24 h after exposure. Cytotoxic activity was assayed at 1 h after exposure, while perforin and NKG2D expression were detected at 1 h, 6 h, and 12 h after exposure. To clarify the mechanisms, phosphorylated ERK (p-ERK) was detected at 1 h after exposure. Moreover, microwave-induced cellular apoptosis and cell cycle regulation were analyzed after blockade of ERK signaling by using U0126. Microwave-induced morphological and ultrastructural injury, dose-dependent apoptosis (P < 0.001) and cell cycle arrest (P < 0.001) were detected at 1 h after microwave exposure. Moreover, significant apoptosis was still detected at 24 h after 50 mW/cm2 microwave exposure (P < 0.01). In the 30 mW/cm2 microwave exposure model, microwaves impaired the cytotoxic activity of NK-92 cells at 1 h and down regulated perforin protein both at 1 h and 6 h after exposure (P < 0.05). Furthermore, p-ERK was down regulated at 1 h after exposure (P < 0.05), while ERK blockade significantly promoted microwave-induced apoptosis (P < 0.05) and downregulation of perforin (P < 0.01). Microwave dose-dependently induced morphological and functional injury in NK-92 cells, possibly through ERK-mediated regulation of apoptosis and perforin expression. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Protective Effects of Liposomal N-Acetylcysteine against Paraquat-Induced Cytotoxicity and Gene Expression

PubMed Central

Mitsopoulos, Panagiotis; Suntres, Zacharias E.

2011-01-01

Paraquat (PQ) is a herbicide that preferentially accumulates in the lung and exerts its cytotoxicity via the generation of reactive oxygen species (ROS). There is no specific treatment for paraquat poisoning. Attempts have been made to increase the antioxidant status in the lung using antioxidants (e.g., superoxide dismutase, vitamin E, N-acetylcysteine) but the outcome from such treatments is limited. Encapsulation of antioxidants in liposomes improves their therapeutic potential against oxidant-induced lung damage because liposomes facilitate intracellular delivery and prolong the retention of entrapped agents inside the cell. In the present study, we compared the effectiveness of conventional N-acetylcysteine (NAC) and liposomal-NAC (L-NAC) against PQ-induced cytotoxicity and examined the mechanism(s) by which these antioxidant formulations conferred cytoprotection. The effects of NAC or L-NAC against PQ-induced cytotoxicity in A549 cells were assessed by measuring cellular PQ uptake, intracellular glutathione content, ROS levels, mitochondrial membrane potential, cellular gene expression, inflammatory cytokine release and cell viability. Pretreatment of cells with L-NAC was significantly more effective than pretreatment with the conventional drug in reducing PQ-induced cytotoxicity, as indicated by the biomarkers used in this study. Our results suggested that the delivery of NAC as a liposomal formulation improves its effectiveness in counteracting PQ-induced cytotoxicity. PMID:21584258

The Spectrum of Mitochondrial Ultrastructural Defects in Mitochondrial Myopathy

PubMed Central

Vincent, Amy E.; Ng, Yi Shiau; White, Kathryn; Davey, Tracey; Mannella, Carmen; Falkous, Gavin; Feeney, Catherine; Schaefer, Andrew M.; McFarland, Robert; Gorman, Grainne S.; Taylor, Robert W.; Turnbull, Doug M.; Picard, Martin

2016-01-01

Mitochondrial functions are intrinsically linked to their morphology and membrane ultrastructure. Characterizing abnormal mitochondrial structural features may thus provide insight into the underlying pathogenesis of inherited and acquired mitochondrial diseases. Following a systematic literature review on ultrastructural defects in mitochondrial myopathy, we investigated skeletal muscle biopsies from seven subjects with genetically defined mtDNA mutations. Mitochondrial ultrastructure and morphology were characterized using two complimentary approaches: transmission electron microscopy (TEM) and serial block face scanning EM (SBF-SEM) with 3D reconstruction. Six ultrastructural abnormalities were identified including i) paracrystalline inclusions, ii) linearization of cristae and abnormal angular features, iii) concentric layering of cristae membranes, iv) matrix compartmentalization, v) nanotunelling, and vi) donut-shaped mitochondria. In light of recent molecular advances in mitochondrial biology, these findings reveal novel aspects of mitochondrial ultrastructure and morphology in human tissues with implications for understanding the mechanisms linking mitochondrial dysfunction to disease. PMID:27506553

[Effect of hemosorption on the ultrastructure of hepatocytes in toxic liver damage].

PubMed

Kasymov, A Kh; Kasymov, Sh Z; Vorozheĭkin, V M; Kirichenko, I P

1985-03-01

Extracorporeal perfusion of toxic blood via carbonic sorbents is an effective method for correcting severe disturbances of hemostasis. Ultrastructural alterations in hepatic cells were studied in experimental toxic liver injury before and after hemosorption. It was established that after hemosorption the processes of intracellular regeneration were significantly activated in the liver parenchyma. The number of crysts in the mitochondria increased as did the electronic density of the matrix. At the same time the number of lysosomes rose as well. However, in persistent unresolved cholestasis, destructive alterations in the hepatic tissue progressed despite the performance of hemosorption.

Effects of in vivo hydrocortisone on lymphocyte-mediated cytotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katz, P.; Zaytoun, A.M.; Lee, J.H. Jr.

To examine the effects of in vivo hydrocortisone sodium succinate (HC) on natural killer (NK) cell and antibody-dependent cellular cytotoxicity (ADCC), 11 normal adults received a single intravenous bolus of 400 mg hydrocortisone. Lymphocytes were tested for NK activity and ADCC using 51chromium (51Cr)-release and single cell cytotoxicity assays against Molt-4 and sensitized RL O leads to target cells, respectively. Four hours after injection, both NK and ADCC activity were transiently increased in the 51Cr-release system. At 4 hours, there was a twofold increase in the relative frequency of potentially cytotoxic target binding cells but the absolute number of thesemore » cells did not change. However, the percentage lysis of bound targets at 4 hours was not altered. These data suggest that: 1) lymphocytes participating in NK and ADCC reactions are refractory to the kinetic and functional effects of HC; 2) the increased lytic activity observed at 4 hours is due to a selective depletion of noncytotoxic cells from the circulation; and 3) NK and ADCC activity did not differ in their responses to HC.« less

Cytotoxic and hemolytic effects of Tritrichomonas foetus on mammalian cells.

PubMed Central

Burgess, D E; Knoblock, K F; Daugherty, T; Robertson, N P

1990-01-01

Geographically distinct lines of Tritrichomonas foetus were assayed for their ability to cause cytotoxicity in nucleated mammalian cells and lysis of bovine erythrocytes. T. foetus was highly cytotoxic toward a human cervical cell line (HeLa) and early bovine lymphosarcoma (BL-3) but displayed low levels of cytotoxicity against African green monkey kidney (Vero) cells. In addition to variation in the extent of cytotoxicity toward different targets, differences in the levels of cytotoxicity in the same nucleated target occurred with different parasite lines. Whole T. foetus, unfractionated whole-cell extracts, and parasite-conditioned medium (RPMI 1640 without serum) all caused lysis of bovine erythrocytes. Lytic activity in the conditioned medium was substantially reduced by repeated freezing and thawing or heating to 90 degrees C for 30 min. Damage of mammalian target cells by live T. foetus could be reduced by the presence of protease inhibitors; however, such inhibitors did not diminish the lytic effects of conditioned medium. These results suggested that proteolytic enzymes were necessary for the lytic mechanism of the live parasites but were not required once lytic factors were released into the parasite-conditioned medium. They further suggested that the lytic molecules were either proteins or had proteinaceous components. Images PMID:2228233

Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers.

PubMed

van Haaften, Caroline; Duke, Colin C; Weerheim, Arij M; Smit, Nico Pm; van Haard, Paul Mm; Darroudi, Firouz; Trimbos, Baptist Jmz

2011-03-14

Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen. The leaves of a plant endemic to Australia, Calomeria amaranthoides, were extracted and then fractionated by column chromatography. In vitro cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 μg/mL (crude extract) and 1-10 μg/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue.In vivo cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR3 cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test. Two compounds were isolated by chromatographic fractionation and identified by 1H-NMR, 13C-NMR and mass spectrometry analyses, EPD, an α-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an α-methylene carboxylic acid.Cytotoxicity of EPD for normal fibroblasts at all time points IC50 was greater than 10 μg/mL, whereas, for OVCAR3 cells at 48 hours IC50 was 5.3 μg/mL (95% confidence interval 4.3 to 6.5 μg/mL).Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 μg/mL and 5 μg/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects.Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13. For the first time both crude plant extract

Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers

PubMed Central

2011-01-01

Background Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen. Methods The leaves of a plant endemic to Australia, Calomeria amaranthoides, were extracted and then fractionated by column chromatography. In vitro cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 μg/mL (crude extract) and 1-10 μg/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue. In vivo cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR3 cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test. Results Two compounds were isolated by chromatographic fractionation and identified by 1H-NMR, 13C-NMR and mass spectrometry analyses, EPD, an α-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an α-methylene carboxylic acid. Cytotoxicity of EPD for normal fibroblasts at all time points IC50 was greater than 10 μg/mL, whereas, for OVCAR3 cells at 48 hours IC50 was 5.3 μg/mL (95% confidence interval 4.3 to 6.5 μg/mL). Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 μg/mL and 5 μg/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects. Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13. Conclusions

Effect of insulin-like growth factor-1 on corneal surface ultrastructure and nerve regeneration of rabbit eyes after laser in situ keratomileusis.

PubMed

Wang, Chunyan; Peng, Yanli; Pan, Shuling; Li, Li

2014-01-13

To explore the effect of insulin-like growth factor-1 (IGF-1) on corneal surface ultrastructure and nerve regeneration in rabbit models after laser in situ keratomileusis (LASIK). Forty-two healthy New Zealand white rabbits were divided into two groups, the IGF-1 group and the control group, and LASIK surgery was performed. The corneal surface ultrastructure was observed by transmission electron microscopy, and the nerve regeneration was evaluated by counting the newly regenerated nerves at 1 d, 1 w, 2 w, 1 m, 3 m and 6 m after surgery. Dry eye parameters, including the Schirmer I test and tear break-up time, were examined at all time points. The examination of corneal ultrastructure showed that the number of corneal epithelial microvilli in the IGF-1 group was significantly higher than that in the normal saline (NS) group except in the second postoperative week (p<0.05). The observation of corneal nerve regeneration showed that the number of regenerated nerve fibers in the IGF-1 group was higher than the control group at all time points (p<0.05). The parameters of dry eye were significantly higher in the IGF-1 group compared to the control group at all time points except at 1d and 6m after LASIK. IGF-1 can effectively accelerate the early repair of corneal surface ultrastructure and nerve regeneration after LASIK and relieve dry eye symptoms in rabbit eyes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Cancer cell specific cytotoxic effect of Rhoeo discolor extracts and solvent fractions.

PubMed

García-Varela, Rebeca; Fajardo Ramírez, Oscar Raúl; Serna-Saldivar, Sergio O; Altamirano, Julio; Cardineau, Guy A

2016-08-22

Traditional or folk medicine has led to the discovery of important bioactive substances used in several health-related areas. Phytochemicals in Rhoeo discolor (R. discolor) extracts have proven to have important cancer cell specific cytotoxic activity. In the present research, we determined the cytotoxic effect of extracts of R. discolor, a plant commonly used in Mexico for both medicinal and ornamental purposes. We evaluated the cytotoxic effects against three representative human cancer cell lines: HT-29 colon cancer, Hep-G2 liver cancer and PC-3 prostate cancer cell lines, as well as a control fibroblast cell line NIH 3T3. Ten different crude extracts were tested along with fractions derived from the five most bioactive crude extracts. Analytical data, HPLC-MS-TOF, revealed a high content of phenolic compounds such as anthocyanins, ferulic, vanillic, chlorogenic and p-coumaric acid in the extracts. Phenolic compounds have previously been reported as health beneficial with antioxidant and potential cancer specific cytotoxic effects. Studies revealed that low concentrations of these crude bioactive extracts (10µg/ml) and their fractions (50µg/ml) were effective as cancer specific cytotoxic agents, since they caused a significant proliferation inhibition on cancer cell lines (up to 94.2% in HT-29, 92.9% in Hep-G2 and 61.8% in PC-3 of apoptosis induction) with little harm to the control cell line (no higher than 28.3% apoptosis induction), and, importantly, the most effective extracts were mainly water, methanol and ethanol based. These results suggest that a diet containing these compounds may function as a medical aid or chemoprotective. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Cytotoxic effect of Vibrio cholerae non-O1 on Vero cells].

PubMed

Figueroa-Arredondo, P; García-Lozano, H; Gutiérrez-Cogco, L; Valdespino-Gómez, J L

1994-01-01

At the present time there is still in Mexico a diarrhoeal outbreak due to Vibrio cholerae O1. In INDRE we have isolated from the same outbreak last year (jan-apr), 70 strains of Vibrio cholerae Non-O1. These were isolated from patients with a diarrhoeal illness different from cholera. Patients were of different ages and sex, and from various geographic areas. The isolated strains were confirmed by serological agglutination test with polyclonal antisera, and they neither belong to O1 serogroup or O139. We assayed all the 70 strains in Vero cells, searching for cytotoxic effect, probably attributed to cholera toxin, or any other toxin. The strains were screened by PCR for cholera toxin gene detection, and negative results were obtained. We have found only one CT-producer strain, but it was a rough one so, we are not able to affirm that is not a V. cholerae O1 serotype. Vibrio cholerae Non-O1 strains, tested in Vero cells assay, produced cytotoxic effect within 24 h. It was found that 48/70 strains (66.6%), had cytotoxic activity, showing rounding and then lysis of cells. From our results we concluded that this cytotoxic effect, is not cholera toxin related, instead we propose it could be due to an unknown virulence factor, probably a different toxin in mexican Vibrio cholerae Non-O1 strains.

Cytotoxic Effect Associated with Overexpression of QNR Proteins in Escherichia coli.

PubMed

Machuca, Jesús; Diaz de Alba, Paula; Recacha, Esther; Pascual, Álvaro; Rodriguez-Martinez, José Manuel

2017-10-01

The objective was to evaluate the cytotoxic effect associated with overexpression of multiple Qnr-like plasmid-mediated quinolone resistance (PMQR) mechanisms in Escherichia coli. Coding regions of different PMQR genes (qnrA1, qnrB1, qnrC, qnrD1, qnrS1, and qepA2) and efsqnr were cloned into pET29a(+) vector and overexpressed in E. coli BL21. E. coli BL21 with and without an empty pET29a(+) vector were used as controls. The cytotoxic effect associated with PMQR mechanism overexpression was determined by transmission electron microscopy and viability assays. Overexpressed qnr genes produced loss of bacterial viability in the range of 77-97% compared with the controls, comparable with loss of viability associated with EfsQnr overexpression (97%). No loss of viability was observed in E. coli overexpressing QepA2. In transmission electron microscopy assays, signs of cytotoxicity were observed in E. coli cells overexpressing EfsQnr and Qnr proteins (30-45% of the bacterial population showed morphological changes). Morphological changes were observed in less than 5% of bacterial populations from the control strains and E. coli overexpressing QepA2. Overexpression of qnr genes produces a cytotoxic cellular and structural effect in E. coli, the magnitude of which varies depending on the family of Qnr proteins.

Effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of summer maize.

PubMed

Ren, Baizhao; Cui, Haiyan; Camberato, James J; Dong, Shuting; Liu, Peng; Zhao, Bin; Zhang, Jiwang

2016-08-01

A field experiment was conducted to study the effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of two summer maize hybrids Denghai605 (DH605) and Zhengdan958 (ZD958). The ambient sunlight treatment was used as control (CK) and shading treatments (40 % of ambient sunlight) were applied at different growth stages from silking (R1) to physiological maturity (R6) (S1), from the sixth leaf stage (V6) to R1 (S2), and from seeding to R6 (S3), respectively. The net photosynthetic rate (P n) was significantly decreased after shading. The greatest reduction of P n was found at S3 treatment, followed by S1 and S2 treatments. P n of S3 was decreased by 59 and 48 % for DH605, and 39 and 43 % for ZD958 at tasseling and milk-ripe stages, respectively, compared to that of CK. Additionally, leaf area index (LAI) and chlorophyll content decreased after shading. In terms of mesophyll cell ultrastructure, chloroplast configuration of mesophyll cells dispersed, and part of chloroplast swelled and became circular. Meanwhile, the major characteristics of chloroplasts showed poorly developed thylakoid structure at the early growth stage, blurry lamellar structure, loose grana, and a large gap between slices and warping granum. Then, plasmolysis occurred in mesophyll cells and the endomembrane system was destroyed, which resulted in the dissolution of cell membrane, karyotheca, mitochondria, and some membrane structures. The damaged mesophyll cell ultrastructure led to the decrease of photosynthetic capacity, and thus resulted in significant yield reduction by 45, 11, and 84 % in S1, S2, and S3 treatments, respectively, compared to that of CK.

Ultrastructure Organization of Human Trabeculae Assessed by 3D sSAXS and Relation to Bone Microarchitecture

PubMed Central

Guizar-Sicairos, Manuel; Gschwend, Oliver; Hangartner, Peter; Bunk, Oliver; Müller, Ralph; Schneider, Philipp

2016-01-01

microarchitecture, being oriented mostly parallel to bone surface, and (v) local surface curvature seems to have an effect on the ultrastructure organization. Further studies that investigate bone ultrastructure orientation and arrangement are needed in order to understand its organization and consequently its relation to bone biology and mechanics. PMID:27547973

Effects of different fixation and freeze substitution methods on the ultrastructural preservation of ZYMV-infected Cucurbita pepo (L.) leaves.

PubMed

Zechmann, Bernd; Müller, Maria; Zellnig, Günther

2005-08-01

Different fixation protocols [chemical fixation, plunge and high pressure freezing (HPF)] were used to study the effects of Zucchini yellow mosaic virus (ZYMV) disease on the ultrastructure of adult leaves of Styrian oil pumpkin plants (Cucurbita pepo L. subsp. pepo var. styriaca Greb.) with the transmission electron microscope. Additionally, different media were tested for freeze substitution (FS) to evaluate differences in the ultrastructural preservation of cryofixed plant leaf cells. FS was either performed in (i) 2% osmium tetroxide in anhydrous acetone containing 0.2% uranyl acetate, (ii) 0.01% safranin in anhydrous acetone, (iii) 0.5% glutaraldehyde in anhydrous acetone or (iv) anhydrous acetone. No ultrastructural differences were found in well-preserved cells of plunge and high pressure frozen samples. Cryofixed cells showed a finer granulated cytosol and smoother membranes, than what was found in chemically fixed samples. HPF led in comparison to plunge frozen plant material to an excellent preservation of vascular bundle cells. The use of FS-media such as anhydrous acetone, 0.01% safranin and 0.5% glutaraldehyde led to low membrane contrast and did not preserve the inner fine structures of mitochondria. Additionally, the use of 0.5% glutaraldehyde caused the cytosol to be fuzzy and partly loosened. ZYMV-induced ultrastructural alterations like cylindrical inclusions and dilated ER-cisternae did not differ between chemically fixed and cryofixed cells and were found within the cytosol of infected leaf cells and within sieve tube elements. The results demonstrate specific structural differences depending on the FS-medium used, which has to be considered for investigations of selected cell structures.

Finite element modeling of hyper-viscoelasticity of peripheral nerve ultrastructures.

PubMed

Chang, Cheng-Tao; Chen, Yu-Hsing; Lin, Chou-Ching K; Ju, Ming-Shaung

2015-07-16

The mechanical characteristics of ultrastructures of rat sciatic nerves were investigated through animal experiments and finite element analyses. A custom-designed dynamic testing apparatus was used to conduct in vitro transverse compression experiments on the nerves. The optical coherence tomography (OCT) was utilized to record the cross-sectional images of nerve during the dynamic testing. Two-dimensional finite element models of the nerves were built based on their OCT images. A hyper-viscoelastic model was employed to describe the elastic and stress relaxation response of each ultrastructure of the nerve, namely the endoneurium, the perineurium and the epineurium. The first-order Ogden model was employed to describe the elasticity of each ultrastructure and a generalized Maxwell model for the relaxation. The inverse finite element analysis was used to estimate the material parameters of the ultrastructures. The results show the instantaneous shear modulus of the ultrastructures in decreasing order is perineurium, endoneurium, and epineurium. The FE model combined with the first-order Ogden model and the second-order Prony series is good enough for describing the compress-and-hold response of the nerve ultrastructures. The integration of OCT and the nonlinear finite element modeling may be applicable to study the viscoelasticity of peripheral nerve down to the ultrastructural level. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cytotoxic Drug Dispersal, Cytotoxic Safety, and Cytotoxic Waste Management: Practices and Proposed India-specific Guidelines

PubMed Central

Capoor, Malini R; Bhowmik, Kumar Tapas

2017-01-01

This article deals with practices related to cytotoxic drug dispersal, cytotoxic safety, and cytotoxic waste management and attempts at India-specific guidelines for their dispersal and disposal. The articles related to cytotoxic drug dispersal, cytotoxic safety, and cytotoxic waste management were reviewed from PubMed and their applicability in Indian health-care facilities (HCFs) was also reviewed. All HCFs dealing with cytotoxic drugs should consider cytotoxic policy, patient safety and health-care worker safety, and environmental monitoring program as per the available international guidelines customized as per Indian conditions. Utmost care in handling cytotoxic waste is quintessential. The formation of India-specific cytotoxic guidelines requires the inputs from all stakeholders. Cytotoxic waste, cytotoxic safety, and cytotoxic waste management should be the subject of a national strategy with an infrastructure, cradle-to-grave legislation, competent regulatory authority, and trained personnel. PMID:28900329

Cytotoxic, antioxidative, genotoxic and antigenotoxic effects of Horchata, beverage of South Ecuador.

PubMed

Bailon-Moscoso, Natalia; Tinitana, Fani; Martínez-Espinosa, Ruth; Jaramillo-Velez, Andrea; Palacio-Arpi, Alejandra; Aguilar-Hernandez, Jessica; Romero-Benavides, Juan Carlos

2017-12-19

"Horchata" is an herbal mixture infusion consumed in Southern Ecuador; 66% of its plants are anti-inflammatory medicinal plant, and 51% are analgesics. Anti-inflammatory substances can prevent carcinogenesis mediated by cytotoxic effects and can prevent DNA damage. The aim of this study was to evaluate the cytotoxicity and apoptotic/antigenotoxic effects of horchata as well as its mechanism. Nine different varieties of horchata were prepared in the traditional way and then freeze-dried. Phytochemical screening tested for the presence of secondary metabolites using standard procedures and antioxidant activities. The cytotoxic activity was evaluated on cerebral astrocytoma (D-384), prostate cancer (PC-3), breast cancer (MCF-7), colon cancer (RKO), lung cancer (A-549), immortalized Chinese hamster ovary cells (CHO-K1), and human peripheral blood lymphocytes via a MTS assay. The pro-apoptotic effects were evaluated with Anexin V/Propidium Iodide and western blot of Bax, Bcl-2, TP53, and TP73. Induction and reduction of ROS were assessed by fluorimetry. Genotoxic and antigenotoxic effects were evaluated with a comet assay and micronuclei on binucleated cells. Five of nine horchatas had cytotoxic effects against D-384 while not affecting normal cells. These horchatas induce cell death by apoptosis modulated by p53/p73. In CHO-K1 cells, the horchatas decrease the damage induced by hydrogen peroxide and Mitomycin C measured in the comet and micronucleus assay respectively. The IC 50 range of effective horchatas in D-384 was 41 to 122 μg·mL -1 . This effect may be related to its use in traditional medicine (brain tonic). On the other hand, immortalized Chinese hamster ovary cells (CHO-K1) and lymphocytes did not show a cytotoxic effect. The most potent horchata induced apoptosis via a p53/p73-mediated mechanism. The horchatas present antigenotoxic properties, which may be related to the antioxidant capacity. Future studies on horchata components are necessary to

[Effect of infrasound on ultrastructure and permeability of rat's blood-retinal barrier].

PubMed

Qiu, Ping; Zhang, Zuoming; Jiang, Yong; Gou, Qun; Wang, Bing; Gou, Lin; Chen, Jingzao

2002-08-01

To investigate the possible effect of infrasound on the ultra-structure and permeability of rat's blood-retinal barrier (BRB). Ultra-structural changes of BRB were observed through the injection of lanthanum nitrate (La), which was used as a tracer to demonstrate the breakdown of the BRB, into blood vessels. Fifteen mature male rats divided into 5 groups were exposed to infrasound at a 8 Hz frequency, 130 dB sound pressure level in a pressure chamber especially designed for the experiment for 0, 1, 7, 14, 21 days, respectively. Under the action of infrasound, along with the prolongation of exposure, the damage of BRB was severer and severer. On the 1st day, there was no significant change in La leakage. On the 7th day, La diffused in the interphotoreceptor space at nuclear level. On the 14th day, La granules could be seen in the space of nervous cells. Finally, on the 21st day, La was found between synapses, synapses and nerve cells, as well as between the nerve cells and supporting cells, then sometimes reached vitreous body. Under the electron microscope, there were no significant morphological changes, but changes related to metabolism, such as edematous mitochondria, dilated rough endoplasmic reticula, precipitation of glycogen grandules, widening of perinuclear space, etc. The results thus suggest that the exposure to infrasound cause the breakdown of rat's blood-retinal barrier and visual impairment.

Selective cytotoxic effect of non-thermal micro-DBD plasma

NASA Astrophysics Data System (ADS)

Kwon, Byung-Su; Choi, Eun Ha; Chang, Boksoon; Choi, Jeong-Hyun; Kim, Kyung Sook; Park, Hun-Kuk

2016-10-01

Non-thermal plasma has been extensively researched as a new cancer treatment technology. We investigated the selective cytotoxic effects of non-thermal micro-dielectric barrier discharge (micro-DBD) plasma in cervical cancer cells. Two human cervical cancer cell lines (HeLa and SiHa) and one human fibroblast (HFB) cell line were treated with micro-DBD plasma. All cells underwent apoptotic death induced by plasma in a dose-dependent manner. The plasma showed selective inhibition of cell proliferation in cervical cancer cells compared to HFBs. The selective effects of the plasma were also observed between the different cervical cancer cell lines. Plasma treatment significantly inhibited the proliferation of SiHa cells in comparison to HeLa cells. The changes in gene expression were significant in the cervical cancer cells in comparison to HFBs. Among the cancer cells, apoptosis-related genes were significantly enriched in SiHa cells. These changes were consistent with the differential cytotoxic effects observed in different cell lines.

Histological and Ultrastructural Effects of Ultrasound-induced Cavitation on Human Skin Adipose Tissue.

PubMed

Bani, Daniele; Quattrini Li, Alessandro; Freschi, Giancarlo; Russo, Giulia Lo

2013-09-01

In aesthetic medicine, the most promising techniques for noninvasive body sculpturing purposes are based on ultrasound-induced fat cavitation. Liporeductive ultrasound devices afford clinically relevant subcutaneous fat pad reduction without significant adverse reactions. This study aims at evaluating the histological and ultrastructural changes induced by ultrasound cavitation on the different cell components of human skin. Control and ultrasound-treated ex vivo abdominal full-thickness skin samples and skin biopsies from patients pretreated with or without ultrasound cavitation were studied histologically, morphometrically, and ultrastructurally to evaluate possible changes in adipocyte size and morphology. Adipocyte apoptosis and triglyceride release were also assayed. Clinical evaluation of the effects of 4 weekly ultrasound vs sham treatments was performed by plicometry. Compared with the sham-treated control samples, ultrasound cavitation induced a statistically significant reduction in the size of the adipocytes (P < 0.001), the appearance of micropores and triglyceride leakage and release in the conditioned medium (P < 0.05 at 15 min), or adipose tissue interstitium, without appreciable changes in microvascular, stromal, and epidermal components and in the number of apoptotic adipocytes. Clinically, the ultrasound treatment caused a significant reduction of abdominal fat. This study further strengthens the current notion that noninvasive transcutaneous ultrasound cavitation is a promising and safe technology for localized reduction of fat and provides experimental evidence for its specific mechanism of action on the adipocytes.

Cytotoxicity of denture base resins: effect of water bath and microwave postpolymerization heat treatments.

PubMed

Jorge, Janaina Habib; Giampaolo, Eunice Teresinha; Vergani, Carlos Eduardo; Machado, Ana Lúcia; Pavarina, Ana Cláudia; Carlos, Iracilda Zeppone

2004-01-01

This study compared the effect of two postpolymerization heat treatments on the cytotoxicity of three denture base resins on L929 cells using 3H-thymidine incorporation and MTT assays. Sample disks of Lucitone 550, QC 20, and Acron MC resins were fabricated under aseptic conditions and stored in distilled water at 37 degrees C for 48 hours. Specimens were then divided into three groups: (1) heat treated in microwave oven for 3 minutes at 500 W; (2) heat treated in water bath at 55 degrees C for 60 minutes; and (3) no heat treatment. Eluates were prepared by placing three disks into a sterile glass vial with 9 mL of Eagle's medium and incubating at 37 degrees C for 24 hours. The cytotoxic effect from the eluates was evaluated using the 3H-thymidine incorporation and MTT assays, which reflect DNA synthesis levels and cell metabolism, respectively. The components leached from the resins were cytotoxic to L929 cells when 3H-thymidine incorporation assay was employed. In contrast, eluates from all resins revealed noncytotoxic effects as measured by MTT assay. For both MTT assay and 3H-thymidine incorporation, the heat treatments did not decrease the cytotoxicity of the materials tested. Resins were graded by 3H-thymidine incorporation assay as slightly cytotoxic and by MTT assay as noncytotoxic. Cytotoxicity of the denture base materials was not influenced by microwave or water bath heat treatment.

Effect of N-acetyl cysteine on orthodontic primers cytotoxicity.

PubMed

D'Antò, Vincenzo; Spagnuolo, Gianrico; Schweikl, Helmut; Rengo, Sandro; Ambrosio, Luigi; Martina, Roberto; Valletta, Rosa

2011-02-01

The aims of this study were to evaluate the cytotoxicity of four orthodontic primers, including two hydrophilic and two hydrophobic materials, and to investigate the role of the reactive oxygen species (ROS) in induced cell damage. Moreover, the effects of the anti-oxidant N-acetyl cysteine (NAC) on primers toxicity was analyzed. Human gingival fibroblasts (HGF) were exposed to different concentrations of primers (0-0.25 mg/ml) in the presence or absence of NAC, and the cytotoxicity was assessed by the MTT assay, while cell death was quantified by flow cytometry after propidium iodide staining. The increase in the induced ROS levels was detected by flow cytometry measuring the fluorescence of the oxidation-sensitive dye 2',7'-dichlorofluorescein diacetate (DCFH-DA). All materials decreased cell viability in a dose-related manner after a 24 h exposure period. Cytotoxicity of orthodontic primers based on concentrations which caused a 50% decrease in cell viability (TC₅₀) in HGF was ranked as follows (median values): Eagle Fluorsure (0.078 mg/ml)>Transbond XT (0.081 mg/ml)>Transbond MIP (0.128 mg/ml)>Ortho solo (0.130 mg/ml). Moreover, in HGF cells, all materials induced a dose-dependent increase in ROS levels compared to untreated cells. Incubation of HGF with NAC significantly reduced ROS production and decreased the cell damage and cytotoxicity caused by all materials tested (p<0.001). Our results suggested that hydrophilic primers were less cytotoxic than hydrophobic materials. Moreover, we demonstrated a major role of ROS in the induction of cell death since the antioxidant N-acetyl cysteine was able to prevent cell damage induced by all materials tested. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

The effects of Euphorbia hirta on the ultrastructure of the murine liver, kidney and aorta

PubMed Central

WONG, J.Y.R.; CHEN, Y.S.; CHAKRAVARTHI, S.; JUDSON, J.P.; L., SANTHANA RAJ; ER, H.M.

2013-01-01

Euphorbia hirta is widely used in traditional remedies and has been used cross-culturally for generations against maladies such as asthma, skin ailments and hypertension. Previous studies have demonstrated that Euphorbia hirta has antibacterial activity, and have also indicated certain antimolluscidal, antimalarial and anti-inflammatory properties, the latter of which have been suggested to be more pronounced than those of the rheumatological drug, etanercept. To date, no studies have identified the anatomical effects of this herb on the organs of test animals. This study aimed to identify the effects of Euphorbia hirta on the ultrastructure of the murine liver, kidney and aorta. A total of 32 adult male Sprague-Dawley rats were divided into four groups; three groups were fed with aqueous extracts of Euphorbia hirta at doses of 1, 10 and 50 mg/kg, respectively, every alternate day for 50 days, while one group served as a control. The animals were later sacrificed and the liver, kidney and aorta harvested for examination by electron microscopy. The aorta showed no ultrastructural changes across the groups. Renal and hepatic tissue from the treated groups demonstrated dose-dependent injuries, which showed architectural damage beginning in the nuclei and spreading outwards. Taking into consideration the properties of Euphorbia hirta that have been described in previous studies, in addition to the results from the present study, it appears that the herb may exhibit similar effects to those of the quinolone group of antibiotics. Further in-depth investigations are required into the potential effects of Euphorbia hirta, deleterious and otherwise. PMID:24223653

Cytotoxic, anti-cancer, and anti-microbial effects of different extracts obtained from Artemisia rupestris.

PubMed

Nokerbek, Shamshabanu; Sakipova, Zuriyadda; Chalupová, Marta; Nejezchlebová, Marcela; Hošek, Jan

2017-01-01

Artemisia rupestris is a part of traditional Kazakh folk medicine. Extracts obtained from this plant are used to treat various diseases, including cancer. This study evaluates the anti-microbial, cytotoxic, and anti-cancer effects of different extracts of the plant. Different extraction techniques were used and the resultant activities were compared. Extracts of A. rupestris were prepared from the flowers plus the leaves and from the stems. The antimicrobial activity against Candida albicans and Staphylococcus aureus was quantified. Cell lines L1210 and THP-1 were used to evaluate the cytotoxic potential of these extracts in vitro. The anti-cancer effect was tested using L1210-induced tumorgenesis in mouse model. The aqueous extract of stems was the most active against C. albicans, whereas the methanolic extract of flowers plus leaves especially inhibited the growth of S. aureus. The aqueous extracts were found to be non-cytotoxic for both cell lines, whereas the lipophilic extracts showed cytotoxic effects. The extract obtained from flowers plus leaves was more cytotoxic than that from stems. The tested extracts showed no anti-cancer potential. The results obtained testify to the relatively safe consumption of aqueous extracts of A. rupestris, but lipophilic extracts showed toxic effects and their consumption should be considered more carefully.Key words: L1210 cell line THP-1 cell line microwave-assisted extraction ultrasonic-assisted extraction Candida albicans Staphylococcus aureus.

Cytotoxicity of lidocaine to human corneal endothelial cells in vitro.

PubMed

Yu, Hao-Ze; Li, Yi-Han; Wang, Rui-Xin; Zhou, Xin; Yu, Miao-Miao; Ge, Yuan; Zhao, Jun; Fan, Ting-Jun

2014-04-01

Lidocaine has been reported to induce apoptosis on rabbit corneal endothelial cells. However, the apoptotic effect and exact mechanism involved in cytotoxicity of lidocaine are not well-established in human corneal endothelial (HCE) cells. In this study, we investigated the apoptosis-inducing effect of lidocaine on HCE cells in vitro. After HCE cells were treated with lidocaine at concentrations of 0.15625-10.0 g/l, the morphology and ultrastructure of the cells were observed by inverted light microscope and transmission electron microscope (TEM). Cell viability was measured by MTT assay, and the apoptotic ratio was evaluated with flow cytometry and fluorescent microscopic counting after FITC-Annexin V/PI and AO/EB staining. DNA fragmentation was detected by electrophoresis, and the activation of caspases was evaluated by ELISA. In addition, changes in mitochondrial membrane potential were determined by JC-1 staining. Results suggest that lidocaine above 1.25 g/l reduced cellular viability and triggered apoptosis in HCE cells in a time- and dose-dependent manner. Diminishment of ΔΨm and the activation of caspases indicate that lidocaine-induced apoptosis was caspase dependent and may be related to mitochondrial pathway. © 2013 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Neem oil (Azadirachta indica A. Juss) affects the ultrastructure of the midgut muscle of Ceraeochrysa claveri (Navás, 1911) (Neuroptera: Chrysopidae).

PubMed

Scudeler, Elton Luiz; Garcia, Ana Silvia Gimenes; Pinheiro, Patricia Fernanda Felipe; Santos, Daniela Carvalho Dos

2017-01-01

Cytomorphological changes, by means of ultrastructural analyses, have been used to determine the effects of the biopesticide neem oil on the muscle fibers of the midgut of the predator Ceraeochrysa claveri. Insects, throughout the larval period, were fed eggs of Diatraea saccharalis treated with neem oil at a concentration of 0.5%, 1% or 2%. In the adult stage, the midgut was collected from female insects at two stages of adulthood (newly emerged and at the start of oviposition) and processed for ultrastructural analyses. In the newly emerged insects obtained from neem oil treatments, muscle fibers showed a reduction of myofilaments as well as swollen mitochondria and an accumulation of membranous structures. Muscular fibers responded to those cellular injuries with the initiation of detoxification mechanisms, in which acid phosphatase activity was observed in large vesicles located at the periphery of the muscle fiber. At the start of oviposition in the neem oil treated insects, muscle fibers exhibited signs of degeneration, containing vacant areas in which contractile myofilaments were reduced or completely absent, and an accumulation of myelin structures, a dilatation of cisternae of sarcoplasmic reticulum, and mitochondrial swelling and cristolysis were observed. Enzymatic activity for acid phosphatase was present in large vesicles, indicating that mechanisms of lytic activity during the cell injury were utilized but insufficient for recovery from all the cellular damage. The results indicate that the visceral muscle layer is also the target of action of neem oil, and the cytotoxic effects observed may compromise the function of that organ. Copyright © 2016 Elsevier GmbH. All rights reserved.

Effects of heavy metals on Cyanothece sp. CCY 0110 growth, extracellular polymeric substances (EPS) production, ultrastructure and protein profiles.

PubMed

Mota, Rita; Pereira, Sara B; Meazzini, Marianna; Fernandes, Rui; Santos, Arlete; Evans, Caroline A; De Philippis, Roberto; Wright, Phillip C; Tamagnini, Paula

2015-04-29

The effects of several heavy metals on the growth/survival, EPS production, ultrastructure and protein profiles of the highly efficient extracellular polymeric substances (EPS)-producer cyanobacterium Cyanothece sp. CCY 0110 were evaluated. Our results clearly show that each heavy metal affects the cells in a particular manner, triggering distinctive responses. Concerning chronic exposure, cells were more affected by Cu(2+) followed by Pb(2+), Cd(2+), and Li(+). The presence of metal leads to remarkable ultrastructural changes, mainly at the thylakoid level. The comparison of the proteomes (iTRAQ) allowed to follow the stress responses and to distinguish specific effects related to the time of exposure and/or the concentration of an essential (Cu(2+)) and a non-essential (Cd(2+)) metal. The majority of the proteins identified and with fold changes were associated with photosynthesis, CO2 fixation and carbohydrate metabolism, translation, and nitrogen and amino acid metabolism. Moreover, our results indicate that during chronic exposure to sub-lethal concentrations of Cu(2+), the cells tune down their metabolic rate to invest energy in the activation of detoxification mechanisms, which eventually result in a remarkable recovery. In contrast, the toxic effects of Cd(2+) are cumulative. Unexpectedly, the amount of released polysaccharides (RPS) was not enhanced by the presence of heavy metals. This work shows the holistic effects of different heavy metals on the cells of the highly efficient EPS-producer the cyanobacterium Cyanothece sp. CCY 0110. The growth/survival, EPS production, ultrastructure, protein profiles and stress response were evaluated. The knowledge generated by this study will contribute to the implementation of heavy-metal removal systems based on cyanobacteria EPS or their isolated polymers. Copyright © 2015. Published by Elsevier B.V.

Neutral sphingomyelinase 2 modulates cytotoxic effects of protopanaxadiol on different human cancer cells

PubMed Central

2013-01-01

Background Some of ginsenosides, root extracts from Panax ginseng, exert cytotoxicity against cancer cells through disruption of membrane subdomains called lipid rafts. Protopanaxadiol (PPD) exhibits the highest cytotoxic effect among 8 ginsenosides which we evaluated for anti-cancer activity. We investigated if PPD disrupts lipid rafts in its cytotoxic effects and also the possible mechanisms. Methods Eight ginsenosides were evaluated using different cancer cells and cell viability assays. The potent ginsenoside, PPD was investigated for its roles in lipid raft disruption and downstream pathways to apoptosis of cancer cells. Anti-cancer effects of PPD was also investigated in vivo using mouse xenograft model. Results PPD consistently exerts its potent cytotoxicity in 2 cell survival assays using 5 different cancer cell lines. PPD disrupts lipid rafts in different ways from methyl-β-cyclodextrin (MβCD) depleting cholesterol out of the subdomains, since lipid raft proteins were differentially modulated by the saponin. During disruption of lipid rafts, PPD activated neutral sphingomyelinase 2 (nSMase 2) hydrolyzing membrane sphingomyelins into pro-apoptotic intracellular ceramides. Furthermore, PPD demonstrated its anti-cancer activities against K562 tumor cells in mouse xenograft model, confirming its potential as an adjunct or chemotherapeutic agent by itself in vivo. Conclusions This study demonstrates that neutral sphingomyelinase 2 is responsible for the cytotoxicity of PPD through production of apoptotic ceramides from membrane sphingomyelins. Thus neutral sphingomyelinase 2 and its relevant mechanisms may potentially be employed in cancer chemotherapies. PMID:23889969

Effect of lignin content on changes occurring in poplar cellulose ultrastructure during dilute acid pretreatment

DOE PAGES

Sun, Qining; Foston, Marcus; Meng, Xianzhi; ...

2014-10-14

Obtaining a better understanding of the complex mechanisms occurring during lignocellulosic deconstruction is critical to the continued growth of renewable biofuel production. A key step in bioethanol production is thermochemical pretreatment to reduce plant cell wall recalcitrance for downstream processes. Previous studies of dilute acid pretreatment (DAP) have shown significant changes in cellulose ultrastructure that occur during pretreatment, but there is still a substantial knowledge gap with respect to the influence of lignin on these cellulose ultrastructural changes. This study was designed to assess how the presence of lignin influences DAP-induced changes in cellulose ultrastructure, which might ultimately have largemore » implications with respect to enzymatic deconstruction efforts. Native, untreated hybrid poplar (Populus trichocarpa x Populus deltoids) samples and a partially delignified poplar sample (facilitated by acidic sodium chlorite pulping) were separately pretreated with dilute sulfuric acid (0.10 M) at 160°C for 15 minutes and 35 minutes, respectively . Following extensive characterization, the partially delignified biomass displayed more significant changes in cellulose ultrastructure following DAP than the native untreated biomass. With respect to the native untreated poplar, delignified poplar after DAP (in which approximately 40% lignin removal occurred) experienced: increased cellulose accessibility indicated by increased Simons’ stain (orange dye) adsorption from 21.8 to 72.5 mg/g, decreased cellulose weight-average degree of polymerization (DP w) from 3087 to 294 units, and increased cellulose crystallite size from 2.9 to 4.2 nm. These changes following DAP ultimately increased enzymatic sugar yield from 10 to 80%. We conclude that, overall, the results indicate a strong influence of lignin content on cellulose ultrastructural changes occurring during DAP. With the reduction of lignin content during DAP, the enlargement of

Photosynthetic and ultrastructural responses of Ulva australis to Zn stress.

PubMed

Farias, D R; Schmidt, E; Simioni, C; Bouzon, Z L; Hurd, C L; Eriksen, R S; Macleod, C K

2017-12-01

This research evaluated the effect of zinc (Zn) on the ultrastructure and the photosynthetic efficiency of a common green alga. Ulva australis was grown in the laboratory for 7days under a range of different Zn concentrations (0, 25, 50 and 100μgL -1 ). Growth rate (Gr), photosynthetic efficiency (Fv/Fm and ETRmax), photosynthetic pigments, and metal accumulation were measured. Samples of 1mm length were taken to analyse the effect of Zn on the ultrastructure using transmission electron microscopy (TEM) and cytochemical responses (TB-O and PAS) were evaluated by light microscopy (LM). There were no significant differences in the growth rate, Fv/Fm, ETRmax and the photosynthetic pigments chlorophyll a, chlorophyll b and carotenoids (p>0.05) after 7days of Zn exposure. However, TEM revealed cytoplasm retraction, compression of cellulose fibrils, dissembled thylakoids and electron-dense bodies suggesting ultrastructural impacts from metal exposure and accumulation. Cytological analysis demonstrated that Zn affected U. australis cells at the three concentrations tested. The main effect was cytoplasm retraction and a decrease on the amount of starch granules, following exposure at 25μgL -1 and 50μgL -1 of Zn. We conclude that concentrations of Zn assessed in U. australis in this research has a short-term cellular effect as revealed by TEM and cytological analysis, demonstrating the importance of measuring a broad suite of endpoints to better understand species responses to environmentally relevant concentrations of Zn. However, U. australis was able to physiologically tolerate adverse conditions, since there was no effect on the photosynthetic performance and growth. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gemcitabine: Selective cytotoxicity, induction of inflammation and effects on urothelial function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farr, Stefanie E; Chess-Williams, Russ; McDermott,

Intravesical gemcitabine has recently been introduced for the treatment of superficial bladder cancer and has a favourable efficacy and toxicity profile in comparison to mitomycin c (MMC), the most commonly used chemotherapeutic agent. The aim of this study was to assess the cytotoxic potency of gemcitabine in comparison to MMC in urothelial cell lines derived from non-malignant (UROtsa) and malignant (RT4 and T24) tissues to assess selectivity. Cells were treated with gemcitabine or mitomycin C at concentrations up to the clinical doses for 1 or 2 h respectively (clinical duration). Treatment combined with hyperthermia was also examined. Cell viability, ROSmore » formation, urothelial function (ATP, acetylcholine and PGE2 release) and secretion of inflammatory cytokines were assessed. Gemcitabine displayed a high cytotoxic selectivity for the two malignant cell lines (RT4, T24) compared to the non-malignant urothelial cells (UROtsa, proliferative and non-proliferative). In contrast, the cytotoxic effects of MMC were non-selective with equivalent potency in each of the cell lines. The cytotoxic effect of gemcitabine in the malignant cell lines was associated with an elevation in free radical formation and was significantly decreased in the presence of an equilibrative nucleoside transporter inhibitor. Transient changes in urothelial ATP and PGE{sub 2} release were observed, with significant increase in release of interleukin-6, interleukin-8 and interleukin-1β from urothelial cells treated with gemcitabine. The selectivity of gemcitabine for malignant urothelial cells may account for the less frequent adverse urological effects with comparison to other commonly used chemotherapeutic agents. - Highlights: • Intravesical gemcitabine has recently been introduced to treat bladder cancer. • Gemcitabine is selectively toxic for malignant urothelial cells. • Urothelial ATP, PGE{sub 2} and inflammatory cytokines were altered by gemcitabine. • Selectivity of

Ultrastructural liver changes in the experimental thyrotoxicosis.

PubMed

Pasyechko, Nadiya Vasylivna; Kuleshko, Iryna Ihorivna; Kulchinska, Veronika Mykolaiivna; Naumova, Liudmyla Valeriivna; Smachylo, Iryna Volodymyrivna; Bob, Anzhela Olehivna; Radetska, Liudmyla Volodymyrivna; Havryliuk, Mykhailo Yevhenovych; Sopel, Olha Mykolaiivna; Mazur, Liudmyla Petrivna

Aim of the study is to evaluate ultrastructural changes of rat liver in experimental thyrotoxicosis. For the study, 36 male rats have been utilized, weighing approximately 150-190 g, which were divided into three groups: the first, control group (12 animals) was composed of healthy rats that received intragastric sodium chloride 0.9% solution, the second group (12 animals) - animals with experimental thyrotoxicosis, which received intragastric solution of L-thyroxine at the rate of 200 μg/kg for 2 weeks, and the third group (12 animals) - rats with experimental thyrotoxicosis, which received intragastric solution of L-thyroxine at the rate of 200 μg/kg for 4 weeks. For electron-microscopic studies small pieces of liver tissue were taken at the end of the 2nd and 4th weeks of the experiment. The material was studied and documented in electron micrographs by using a TEM-125K electron microscope. In experiment in white male rats the electron-microscopic state of the liver in thyrotoxicosis has been studied. It has been established that thyrotoxicosis is accompanied by the significant changes of the hepatocytes ultrastructure, blood and bile capillaries. Experimental thyrotoxicosis causes significant damage of the liver plasma membranes and intracellular structural components of hepatocytes and endothelial cells. In experimental thyrotoxicosis, on the background of microcirculatory disorders, significant damage of plasmatic and intracellular organoid membranes of hepatocytes in the liver develops, which has an adverse effect on the functionality of the organ. The found ultrastructural changes are aggravated depending on the duration of thyrotoxicosis.

Cytotoxic effect of indigenously fabricated dental magnets for application in prosthodontics.

PubMed

Guttal, Satyabodh Shesharaj; Nadiger, Ramesh K; Shetty, Pravinkumar

2018-01-01

Dental magnets are used for retaining removable prostheses such as a removable partial denture, complete denture, and maxillofacial prosthesis. They provide good retention for the prostheses. However, the elements released from the magnets may be cytotoxic for the tissues. Therefore, it is necessary to evaluate their cytotoxic effect on cell lines. The aim of the study is to check the cytotoxic effect of indigenously fabricated dental magnets on animal cell lines. Neodymium-iron-boron (Nd-Fe-B) magnet was tested for cytotoxicity. The magnet was encased in a teflon cylinder. Magnets were placed in the well tissue-cultured plates together with a suspension containing NIH 3T3 mouse fibroblasts (5 × 10 5 cells/ml). After 3 days of incubation at 37°C, cell viability was determined by mean transit time (MTT) assay. Cells were subsequently dissolved in 100 μl dimethyl sulfoxide with gentle shaking for 2 h at room temperature followed by measurement of absorbance at 570 nm. Eight replicate wells were used at each point in each of four separate measurements. Measured absorbance values were directly used for calculating percent of viable cells remaining after the respective treatment. Data were analyzed statistically with significance level set at P < 0.05. The control group had highest absorbance reading for the MTT assay followed by test group. The lowest values were found with bare Nd-Fe-B magnets. One-way ANOVA test was performed for the data obtained. There was a statistical significant difference seen in the positive control (bare magnets, 44.96) and the test (teflon cased magnets, 96.90) group. More number of viable cells was visible in test group cells indicating that the indigenously fabricated dental magnet did not show any cytotoxicity.

Array tomography: characterizing FAC-sorted populations of zebrafish immune cells by their 3D ultrastructure.

PubMed

Wacker, Irene; Chockley, Peter; Bartels, Carolin; Spomer, Waldemar; Hofmann, Andreas; Gengenbach, Ulrich; Singh, Sachin; Thaler, Marlene; Grabher, Clemens; Schröder, Rasmus R

2015-08-01

For 3D reconstructions of whole immune cells from zebrafish, isolated from adult animals by FAC-sorting we employed array tomography on hundreds of serial sections deposited on silicon wafers. Image stacks were either recorded manually or automatically with the newly released ZEISS Atlas 5 Array Tomography platform on a Zeiss FEGSEM. To characterize different populations of immune cells, organelle inventories were created by segmenting individual cells. In addition, arrays were used for quantification of cell populations with respect to the various cell types they contained. The detection of immunological synapses in cocultures of cell populations from thymus or WKM with cancer cells helped to identify the cytotoxic nature of these cells. Our results demonstrate the practicality and benefit of AT for high-throughput ultrastructural imaging of substantial volumes. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

Heterogeneity of acute myeloblastic leukemia without maturation: an ultrastructural study.

PubMed

Hamamoto, K; Date, M; Taniguchi, H; Nagano, T; Kishimoto, Y; Kimura, T; Fukuhara, S

1995-01-01

We demonstrated by ultrastructural examination that the leukemic blasts of 13 patients with acute myeloblastic leukemia (AML) without maturation (M1 in the French-American-British classification) showed heterogeneous features. In 7 patients, the leukemic blasts had a high level of light microscopic myeloperoxidase positivity (> 50%). Ultrastructurally, the cells were myeloblast-promyelocytes with 100% myeloperoxidase positivity, and these 7 patients appeared to have typical AML. In contrast, the remaining 6 patients had leukemic blasts with a low myeloperoxidase positivity (< 50%) and heterogeneous features. Three had ultrastructural features of myelomonocytic or monocytic lineage, 1 had myelomonocytic cells associated with megakaryoblasts, and 1 had undifferentiated blasts. The former group had a better prognosis than the latter, indicating that ultrastructural analysis of M1 leukemia may help predict the response to therapy.

Solar assisted alkali pretreatment of garden biomass: Effects on lignocellulose degradation, enzymatic hydrolysis, crystallinity and ultra-structural changes in lignocellulose.

PubMed

Gabhane, Jagdish; William, S P M Prince; Vaidya, Atul N; Das, Sera; Wate, Satish R

2015-06-01

A comprehensive study was carried out to assess the effectiveness of solar assisted alkali pretreatment (SAAP) on garden biomass (GB). The pretreatment efficiency was assessed based on lignocellulose degradation, conversion of cellulose into reducing sugars, changes in the ultra-structure and functional groups of lignocellulose and impact on the crystallinity of cellulose, etc. SAAP was found to be efficient for the removal of lignin and hemicellulose that facilitated enzymatic hydrolysis of cellulose. FTIR and XRD studies provided details on the effectiveness of SAAP on lignocellulosic moiety and crystallinity of cellulose. Scanning electron microscopic analysis showed ultra-structural disturbances in the microfibrils of GB as a result of pretreatment. The mass balance closer of 97.87% after pretreatment confirmed the reliability of SAAP pretreatment. Based on the results, it is concluded that SAAP is not only an efficient means of pretreatment but also economical as it involved no energy expenditure for heat generation during pretreatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vitro cytotoxicity of maxillofacial silicone elastomers: effect of accelerated aging.

PubMed

Bal, Bilge Turhan; Yilmaz, Handan; Aydin, Cemal; Karakoca, Seçil; Yilmaz, Sükran

2009-04-01

The purpose of this in vitro study was to evaluate the cytotoxicity of three maxillofacial silicone elastomers at 24, 48, and 72 h on L-929 cells and to determine the effect of accelerated aging on the cytotoxicity of these silicone elastomers. Disc-shaped test samples of maxillofacial silicone elastomers (Cosmesil, Episil, Multisil) were fabricated according to manufacturers' instructions under aseptic conditions. Samples were then divided into three groups: (1) not aged; (2) aged for 150 h with an accelerated weathering tester; and (3) aged for 300 h. Then the samples were placed in Dulbecco's Modified Eagle Medium/Ham's F12 (DMEM/F12) for 24, 48, and 72 h. After the incubation periods, cytotoxicity of the extracts to cultured fibroblasts (L-929) was measured by MTT assay. The degree of cytotoxicity of each sample was determined according to the reference value represented by the cells with a control (culture without sample). Statistical significance was determined by repeated measurement ANOVA (p < 0.01) followed by Duncan's test (p < 0.05). All test materials in each group demonstrated high survival rates in MTT assay (Episil; 93.84%, Multisil; 88.30%, Cosmesil; 87.50%, respectively); however, in all groups, Episil material demonstrated significantly higher cell survival rate after each of the experimental incubation periods (p < 0.05). Accelerated aging for 150 and 300 h had no significant effect on the biocompatibility of maxillofacial silicone elastomers tested (p > 0.05).

Ultrastructural demonstration of chemical modification of melanogenesis in hairless mouse skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nishimura, M.; Gellin, G.A.; Hoshino, S.

1982-02-01

We investigated chemical and physical modifications of the genetically determined ultrastructure of melanosomes. The flank skin of hairless mice was treated with ultraviolet energy (UV) shorter than 320 nm or with a combination of a photosensitizer and UV (PUVA treatment). All melanosomes in the induced melanocytes and those in resident melanocytes in the ear skin showed eumelanogenesis, although the degree of melanin deposition differed considerably according to the induction process. Eumelanogenesis was most advanced in the resident melanocytes while PUVA-induced melanocytes showed more immature premelanosomes. We then topically applied 4-tertiary butyl catechol on the skin. The depigmenting agent caused anmore » appearance of pheomelanosomes. The alteration in melanogenesis was seen most distinctly in premelanosomes of the PUVA-induced cells. Altered ultrastructure was also observed in matured melanosomes; this change was most apparent in the resident melanocytes. These findings indicate that cells with eumelanogenesis may undergo pheomelanogenesis. The present study demonstrated effects of chemicals on genetically determined function of melanocytes by quantitative analysis of melanosome ultrastructure.« less

Cytotoxicity and the effect of cationic peptide fragments against cariogenic bacteria under planktonic and biofilm conditions.

PubMed

Kreling, Paula Fernanda; Aida, Kelly Limi; Massunari, Loiane; Caiaffa, Karina Sampaio; Percinoto, Célio; Bedran, Telma Blanca Lombardo; Spolidorio, Denise Madalena Palomari; Abuna, Gabriel Flores; Cilli, Eduardo Maffud; Duque, Cristiane

2016-10-01

This study evaluated the cytotoxicity and effect of fragments derived from three oral cationic peptides (CP): LL-37, D6-17 and D1-23 against cariogenic bacteria under planktonic and biofilm conditions. For cytotoxicity analysis, two epithelial cell lines were used. The minimum inhibitory concentration and the minimal bactericidal concentration were determined for the CP fragments and the control (chlorhexidine-CHX) against cariogenic bacteria. The fractional inhibitory concentration was obtained for the combinations of CP fragments on Streptococcus mutans. Biofilm assays were conducted with the best antimicrobial CP fragment against S. mutans. The results indicated that D6-17 was not cytotoxic. D1-23, LL-37 and CHX were not cytotoxic in low concentrations. D1-23 presented the best bactericidal activity against S. mutans, S. mitis and S. salivarius. Combinations of CP fragments did not show a synergic effect. D1-23 presented a higher activity against S. mutans biofilm than CHX. It was concluded that D1-23 showed a substantial effect against cariogenic bacteria and low cytotoxicity.

Iris ultrastructure in patients with synechiae as revealed by in vivo laser scanning confocal microscopy : In vivo iris ultrastructure in patients with Synechiae by Laser Scanning Confocal Microscopy.

PubMed

Li, Ming; Cheng, Hongbo; Guo, Ping; Zhang, Chun; Tang, Song; Wang, Shusheng

2016-04-26

Iris plays important roles in ocular physiology and disease pathogenesis. Currently it is technically challenging to noninvasively examine the human iris ultrastructure in vivo. The purpose of the current study is to reveal human iris ultrastructure in patients with synechiae by using noninvasive in vivo laser scanning confocal microscopy (LSCM). The ultrastructure of iris in thirty one patients, each with synechiae but transparent cornea, was examined by in vivo LSCM. Five characteristic iris ultrastructures was revealed in patients with synechiae by in vivo LSCM, which include: 1. tree trunk-like structure; 2. tree branch/bush-like structure; 3. Fruit-like structure; 4. Epithelioid-like structure; 5. deep structure. Pigment granules can be observed as a loose structure on the top of the arborization structure. In iris-associated diseases with Tyndall's Phenomenon and keratic precipitates, the pigment particles are more likely to fall off from the arborization structure. The ultrastructure of iris in patients with synechiae has been visualized using in vivo LSCM. Five iris ultrastructures can be clearly observed, with some of the structures maybe disease-associated. The fall-off of the pigment particles may cause the Tyndall's Phenomenon positive. In vivo LSCM provides a non-invasive approach to observe the human iris ultrastructure under certain eye disease conditions, which sets up a foundation to visualize certain iris-associated diseases in the future.

The Effect of Ultrafine Process on the Dissolution, Antibacterial Activity, and Cytotoxicity of Coptidis rhizoma

PubMed Central

Jiang, Zhen-Yu; Deng, Hai-Ying; Yu, Zhi-Jun; Ni, Jun-Yan; Kang, Si-He

2016-01-01

Background: The dosage of herb ultrafine particle (UFP) depended on the increased level of its dissolution, toxicity, and efficacy. Objective: The dissolution, antibacterial activity, and cytotoxicity of Coptidis rhizoma (CR) UFP were compared with those of traditional decoction (TD). Materials and Methods: The dissolution of berberine (BBR) of CR TD and UFP was determined by high-performance liquid chromatography. The antibacterial activity of CR extract was assayed by plate-hole diffusion and broth dilution method; the inhibitory effect of rat serums against bacteria growth was evaluated after orally given CR UFP or TD extract. The cytotoxicity of CR extract was evaluated by 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay. Results: The dissolution amount of BBR from CR UFP increased 6–8-folds in comparison to TD at 2 min, the accumulative amount of BBR in both UFP and TD group increased in a time-dependent manner. The minimal inhibitory concentrations and minimal bactericidal concentrations of CR UFP extract decreased to 1/2~1/4 of those of TD extract. The inhibitory effect of rat serums against bacteria growth decreased time-dependently, and no statistical difference was observed between two groups at each time point. The 50% cytotoxic concentrations of UFP extract increased 1.66~1.97 fold than those of TD. Conclusions: The antibacterial activity and cytotoxicity of CR UFP increased in a dissolution-effect manner in vitro, the increased level of cytotoxicity was lower than that of antibacterial activity, and the inhibitory effect of rat serums containing drugs of UFP group did not improve. SUMMARY Ultrafine grinding process caused a rapid increase of BBR dissolution from CR.The antibacterial activity and cytotoxicity of UFP extract in vitro increased in a dissolution-effect manner, but the cytotoxicity increased lower than the antibacterial activity.The antibacterial activity of rat serums of UFP group did not improve in comparison to that

The Effect of Spaceflight on the Ultrastructure of the Cerebellum

NASA Technical Reports Server (NTRS)

Holstein, Gay R.; Martinelli, Giorgio P.

2003-01-01

In weightlessness, astronauts and cosmonauts may experience postural illusions as well as motion sickness symptoms known as the space adaptation syndrome. Upon return to Earth, they have irregularities in posture and balance. The adaptation to microgravity and subsequent re-adaptation to Earth occurs over several days. At the cellular level, a process called neuronal plasticity may mediate this adaptation. The term plasticity refers to the flexibility and modifiability in the architecture and functions of the nervous system. In fact, plastic changes are thought to underlie not just behavioral adaptation, but also the more generalized phenomena of learning and memory. The goal of this experiment was to identify some of the structural alterations that occur in the rat brain during the sensory and motor adaptation to microgravity. One brain region where plasticity has been studied extensively is the cerebellar cortex-a structure thought to be critical for motor control, coordination, the timing of movements, and, most relevant to the present experiment, motor learning. Also, there are direct as well as indirect connections between projections from the gravity-sensing otolith organs and several subregions of the cerebellum. We tested the hypothesis that alterations in the ultrastructural (the structure within the cell) architecture of rat cerebellar cortex occur during the early period of adaptation to microgravity, as the cerebellum adapts to the absence of the usual gravitational inputs. The results show ultrastructural evidence for neuronal plasticity in the central nervous system of adult rats after 24 hours of spaceflight. Qualitative studies conducted on tissue from the cerebellar cortex (specifically, the nodulus of the cerebellum) indicate that ultrastructural signs of plasticity are present in the cerebellar zones that receive input from the gravity-sensing organs in the inner ear (the otoliths). These changes are not observed in this region in cagematched

Cytotoxic, mutagenicity, and genotoxicity effects of guanylhydrazone derivatives.

PubMed

Pinhatti, Valéria Rodrigues; da Silva, Juliana; Martins, Tales Leandro Costa; Moura, Dinara Jaqueline; Rosa, Renato Moreira; Villela, Izabel; Stopiglia, Cheila Denise Ottonelli; da Silva Santos, Selma; Scroferneker, Maria Lúcia; Machado, Carlos Renato; Saffi, Jenifer; Henriques, João Antonio Pêgas

2016-08-01

Several studies have reported that guanylhydrazones display a variety of desirable biological properties, such as antihypertensive, antibacterial, and antimalarial behaviour. They furthermore promote anti-pneumocystosis and anti-trypanosomiasis, exhibit antitumor activity, and show significant cytotoxicity against cancer cell lines. In this work, we have evaluated the cytotoxicity, mutagenicity, and genotoxicity of two guanylhydrazones derivatives, (E)-2-[(2,3-dimethoxyphenyl) methylene] hydrazine carboxymidamide hydrochloride (2,3-DMeB) and (E)-2-[(3,4-dimethoxyphenyl) methylene] hydrazine carboxymidamide hydrochloride (3,4-DMeB), in different biological models. Both 2,3-DMeB and 3,4-DMeB induce weak cytotoxic and mutagenic effects in bacteria and yeast. The genotoxicity of these compounds was determined in a fibroblast cell line (V79) using alkaline comet assay, as well as a modified comet assay with bacterial enzymes formamidopyrimidine DNA-glycosylase (FPG) and endonuclease III (EndoIII). Both guanylhydrazone derivatives induced DNA damage. Treatment of V79 cells with EndoIII and FPG proteins demonstrated a significant effect of 2,3-DMeB and 3,4-DMeB with respect to oxidized bases. In addition, the derivatives induced a significant increase in the frequency of micronucleated cells at high doses. The antifungal and anti-trypanosomal properties of these guanylhydrazone derivatives were also evaluated, and the obtained results suggest that 2,3-DMeB is more effective than 3,4-DMeB. The biological activity of 2,3-DMeB and 3,4-DMeB may thus be related, at least in part, to their oxidative potential, as well as to their ability to interact with DNA. Considering the previously reported in vitro antitumor activity of guanylhydrazone derivatives in combination with the lack of acute toxicity and the fact that DNA damage is only observed at high doses should render both compounds good candidates for in vivo studies on antitumor activity. Copyright © 2016 Elsevier B

Adjuvant potential of virgin coconut oil extract on antiretroviral therapy-induced testicular toxicity: An ultrastructural study.

PubMed

Ogedengbe, O O; Jegede, A I; Onanuga, I O; Offor, U; Peter, A I; Akang, E N; Naidu, E C S; Azu, O O

2018-04-01

The effects of Virgin coconut oil as an adjuvant to highly active antiretroviral therapy (HAART) were investigated on the testicular ultrastructure and biochemical markers in rats. Twenty male Sprague-Dawley rats, weighing 153-169 g were divided into four groups and treated as follows: control A (distilled water), B (HAART), C (HAART+Virgin coconut oil 10 ml/kg) and D (Virgin coconut oil [VCO] 10 ml/kg). Testicular segments were evaluated using transmission electron microscopy. Serum was assayed for testosterone, luteinising hormone, follicle stimulating hormone and testicular tissue for malondialdehyde and glutathione. Ultrastructure of basement membrane (Bm), mitochondria and spermatocytes was normal in the control group. HAART-treated group showed significant increase (p < .01) in Bm thickness with significant decrease in Leydig cell nuclear diameter (p < .05) and volume (p < .01) when compared with control group. Mitochondrial cristae appear collapsed, and Sertoli cells showed cytoplasmic vacuolations. HAART+VCO group showed improved ultrastructural details in Bm, and Sertoli cell and Leydig cells show abundant lipid droplets. Virgin coconut oil-treated group showed thinning of Bm with otherwise normal ultrastructural features of organelles. HAART-treated group showed significant increase (p < .01) in testosterone levels. There was no significant effect on malondialdehyde and glutathione levels. Virgin coconut oil improved testicular morphology and reversed HAART-induced ultrastructural alterations. Further studies on putative mechanism are required. © 2017 Blackwell Verlag GmbH.

Intra- and interspecific diversity of ultrastructural markers in Scedosporium.

PubMed

Stepanova, Amaliya A; de Hoog, G Sybren; Vasilyeva, Nataliya V

2016-02-01

Ultrastructural features of conidia, lateral walls of aerial and submerged hyphal cells, and of septal pore apparatus of Scedosporium apiospermum, S. boydii, Pseudallescheria angusta and Scedosporium aurantiacum were studied. Submerged hyphal cells possessed a thick extracellular matrix. Crystalline satellites accessory to the septal pore apparatus were revealed. Fundamental ultrastructural features appeared to be heterogeneous at low taxonomic levels. The closely interrelated members of the S. apiospermum complex showed quantitative ultrastructural variability, but the unambiguously different species S. aurantiacum deviated qualitatively by markers of conidial wall structure, Woronin bodies morphology and presence/absence of crystalline satellites of the septal pore apparatus. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis.

PubMed

Vejux, A; Malvitte, L; Lizard, G

2008-07-01

Oxysterols are 27-carbon atom molecules resulting from autoxidation or enzymatic oxidation of cholesterol. They are present in numerous foodstuffs and have been demonstrated to be present at increased levels in the plasma of patients with cardiovascular diseases and in atherosclerotic lesions. Thus, their role in lipid disorders is widely suspected, and they might also be involved in important degenerative diseases such as Alzheimer's disease, osteoporosis, and age-related macular degeneration. Since atherosclerosis is associated with the presence of apoptotic cells and with oxidative and inflammatory processes, the ability of some oxysterols, especially 7-ketocholesterol and 7beta-hydroxycholesterol, to trigger cell death, activate inflammation, and modulate lipid homeostasis is being extensively studied, especially in vitro. Thus, since there are a number of essential considerations regarding the physiological/pathophysiological functions and activities of the different oxysterols, it is important to determine their biological activities and identify their signaling pathways, when they are used either alone or as mixtures. Oxysterols may have cytotoxic, oxidative, and/or inflammatory effects, or none whatsoever. Moreover, a substantial accumulation of polar lipids in cytoplasmic multilamellar structures has been observed with cytotoxic oxysterols, suggesting that cytotoxic oxysterols are potent inducers of phospholipidosis. This basic knowledge about oxysterols contributes to a better understanding of the associated pathologies and may lead to new treatments and new drugs. Since oxysterols have a number of biological activities, and as oxysterol-induced cell death is assumed to take part in degenerative pathologies, the present review will focus on the cytotoxic activities of these compounds, the corresponding cell death signaling pathways, and associated events (oxidation, inflammation, and phospholipidosis).

Investigation of Light Manipulation by the Ultrastructure of Marine Diatoms

DTIC Science & Technology

2009-11-13

added effect of the semiconductor EL emission is to be identified or its function optimised. In other biological organisms, such as insecta...nanopatterned ultrastructures comprising periodic or quasi-periodic spatial variations in refractive index, give rise to strong photonic effects . These... effects are well documented across a broad range of species through many detailed optical studies13-15. A number of them have gone on to inspire

Marine bivalve geochemistry and shell ultrastructure from modern low pH environments

NASA Astrophysics Data System (ADS)

Hahn, S.; Rodolfo-Metalpa, R.; Griesshaber, E.; Schmahl, W. W.; Buhl, D.; Hall-Spencer, J. M.; Baggini, C.; Fehr, K. T.; Immenhauser, A.

2011-10-01

Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis (from the Mediterranean) and M. edulis (from the Wadden Sea) combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy) were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island of Ischia. The shells of transplanted mussels were compared with M. edulis collected at pH ~8.2 from Sylt (German Wadden Sea). Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

Porosity and test ultrastructure of costate and non-costate Bulimina species

NASA Astrophysics Data System (ADS)

Grunert, Patrick; Piller, Werner E.

2017-04-01

SEM-based investigations of porosity and test wall ultrastructure of Recent costate and non-costate Bulimina species reveal significant differences in pore diameter, pore density and ultrastructural architecture between these two groups. Costate tests of B. inflata and B. mexicana display low pore density, a large pore diameter, and test walls built by a single type of columnar ultrastructural elements. In contrast, non-costate tests of B. aculeata and B. marginata are characterized by significantly higher pore density, smaller pore diameter, and an additional type of ultrastructural elements formed by oblique, tabular crystallite units which encase the pore channels. We interpret the observed combination of traits in B. aculeata and B. marginata as a set of adaptations to poorly oxygenated, intermediate to deep infaunal microhabitats which they typically occupy today. The evolutionary trend towards increased pore density in this group seemingly involved a major modification of the biomineralisation process resulting in the lining of pore channels with a specific type of ultrastructural element to ensure stability of the densely perforated test.

Cytotoxic effects of basic FGF and heparin binding EGF conjugated with cytotoxin saporin on vascular cell cultures.

PubMed

Chen, C; Li, J; Micko, C J; Pierce, G F; Cunningham, M R; Lumsden, A B

1998-02-15

Vascular smooth muscle cell (SMC) proliferation is an integral component of intimal lesion formation. In this study we compared the mitogenic effects of basic fibroblast growth factor (bFGF) and heparin binding epidermal growth factor (HBEGF) and the cytotoxic effects of bFGF and HBEGF conjugated with plant cytotoxin saporin (SAP) on vascular cell cultures. Human vascular SMCs and endothelial cells were cultured and FGF receptor-1 (FGFR-1) and EGF receptor (EGFR) expression were detected by immunohistochemical staining. Cells were grown in 24-well plates. Variable amounts of testing drugs (bFGF, HBEGF, SAP, bFGF-SAP, or HBEGF-SAP) were added to quadruplicate wells after 24 h. Cells without drugs were used as control. The total number of cells was counted at 72 h using a hemocytometer. The cultured human vascular SMCs and endothelial cells expressed both FGFR-1 and EGFR with predominant perinuclear localization. bFGF and HBEGF demonstrated equally potent mitogenic effects on SMC proliferation. SAP alone showed a limited cytotoxic effect on both SMCs and endothelial cells. bFGF had a more potent effect on endothelial cell proliferation than HBEGF. bFGF-SAP was equally cytotoxic for both SMCs and endothelial cells, while HBEGF-SAP had a more selectively cytotoxic effect on SMCs than on endothelial cells. These data suggest that the mitogenic effects of bFGF and HBEGF and the cytotoxic effects of bFGF-SAP and HBEGF-SAP may both be mediated by their corresponding growth factor receptors. Because of its selective cytotoxic effect on SMCs, HBEGF-SAP may become a more attractive agent for controlling intimal lesion formation.

[Effect of electroacupuncture on the behavior and hippocampal ultrastructure in APP 695 V 717 I transgenic mice].

PubMed

Xue, Wei-Guo; Ge, Gui-Ling; Zhang, Zhong; Xu, Hong; Bai, Li-Min

2009-10-01

To investigate the ultrastructural basis underlying electroacupuncture (EA) induced improvement of Alzheimer disease (AD) in transgenic mice. Twelve APP 695 V 717 I transgenic mice were randomly divided into model group and EA group; and other 6 negative transgenic mice (C 57 BL/6 J) were made up of normal control group. After 3 months treatment by EA (15 min per other day, 2 Hz/100 Hz, 3-4 mA) applied to "Baihui" (GV 20) and "Yongquan" (KI 1), the learning and memory ability of mice was measured by Lashley III water maze test, and the ultrastructural changes of hippocampal CA 1 region was observed by electronic microscopy. The swimming escape latency and the number of navigating errors (dead-end forward swimming) in model group were significantly longer and more than those in normal control group (P < 0.05); and those in EA group were considerably shorter and fewer than those in model group (P < 0.05), suggesting an improvement of learning-memory ability after EA. Comparison of the ultrastructure of the neurons in the hippocampal CA 1 region showed swelling of the mitochondria, broken or disappearance of the mitochondrial cristae, degeneration of the synapses, breakage and vague outline of the basement membrane of the blood capillaries in mice of model group; and basically distinct outline of the mitochondrial cristae and microvessels, and more synaptic vesicles in EA group. EA may effectively improve the learning-memory capacity of the APP transgenic AD mice and alleviate the pathological changes of neurons of the hippocampal CA 1 region, which may be one of the mechanisms underlying the improvement of AD by EA.

Shape-dependent antibacterial effects of non-cytotoxic gold nanoparticles

PubMed Central

Penders, Jelle; Stolzoff, Michelle; Hickey, Daniel J; Andersson, Martin; Webster, Thomas J

2017-01-01

Gold nanoparticles (AuNPs) of various shapes (including spheres, stars and flowers), with similar dimensions, were synthesized and evaluated for their antibacterial effects toward Staphylococcus aureus, a bacterium responsible for numerous life-threatening infections worldwide. Optical growth curve measurements and Gompertz modeling showed significant AuNP shape- and concentration-dependent decreases in bacterial growth with increases in bacterial growth lag time. To evaluate prospective use in in vivo systems, the cytotoxicity of the same AuNPs was evaluated toward human dermal fibroblasts in vitro by 3-(4,5 dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) viability assays and confocal microscopy. No indication of any mammalian cell toxicity or morphological effects was found. Additionally, it was observed that the AuNPs were readily internalized in fibroblasts after 4 days of incubation. Most importantly, the results of the present study showed that gold nanoflowers in particular possessed the most promising non-cytotoxic mammalian cell behavior with the greatest shape-dependent antibacterial activity-promising properties for their future investigation in a wide range of anti-infection applications. PMID:28408817

Flight duration and flight muscle ultrastructure of unfed hawk moths.

PubMed

Wone, Bernard W M; Pathak, Jaika; Davidowitz, Goggy

2018-06-13

Flight muscle breakdown has been reported for many orders of insects, but the basis of this breakdown in insects with lifelong dependence on flight is less clear. Lepidopterans show such muscle changes across their lifespans, yet how this change affects the ability of these insects to complete their life cycles is not well documented. We investigated the changes in muscle function and ultrastructure of unfed aging adult hawk moths (Manduca sexta). Flight duration was examined in young, middle-aged, and advanced-aged unfed moths. After measurement of flight duration, the main flight muscle (dorsolongitudinal muscle) was collected and histologically prepared for transmission electron microscopy to compare several measurements of muscle ultrastructure among moths of different ages. Muscle function assays revealed significant positive correlations between muscle ultrastructure and flight distance that were greatest in middle-aged moths and least in young moths. In addition, changes in flight muscle ultrastructure were detected across treatment groups. The number of mitochondria in muscle cells peaked in middle-aged moths. Many wild M. sexta do not feed as adults; thus, understanding the changes in flight capacity and muscle ultrastructure in unfed moths provides a more complete understanding of the ecophysiology and resource allocation strategies of this species. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cytotoxic effect of Reseda lutea L.: A case of forgotten remedy.

PubMed

Radulović, Niko S; Zlatković, Dragan B; Ilić-Tomić, Tatjana; Senerović, Lidija; Nikodinovic-Runic, Jasmina

2014-04-11

Reseda lutea L. (Resedaceae) or Wild Mignonette is a widely distributed plant species. Pliny the Elder (AD 23-AD 79), a Roman scholar and naturalist, reported the use of R. lutea for reducing tumors in his Historia naturalis. Accounts of the beneficial effects of R. lutea in tumor treatment could also be found in the works of later authors, such as Étienne François Geoffroy (1672-1731) and Samuel Frederick Gray (1766-1828). However, to date no in vivo or in vitro evidence exists in support of the alleged tumor healing properties of R. lutea. The composition of autolysates obtained from different organs (root, flower and fruit) of R. lutea was investigated by GC and GC-MS analyses and IR, 1D and 2D NMR spectroscopy. These analyses led to the discovery of a new compound isolated in pure form from the flower autolysate. Autolysates and their major constituents were submitted to MTT-dye reduction cytotoxic assay on human A375 (melanoma) and MRC5 (fibroblast) cell lines. Mechanism of the cytotoxic effects was studied by cell cycle analysis and Annexin V assay. Benzyl isothiocyanate and 2-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate were identified as the major constituents of the root and flower autolysates, respectively (the later represents a new natural product). These compounds showed significant antiproliferative effects against both cell lines, which could also explain the observed high cytotoxic activity of the tested autolysates. Cell cycle analysis revealed apoptosis as the probable mechanism of cell death. Tumor healing properties attributed to R. lutea in the pre-modern texts were substantiated by the herein obtained results. Two isothiocyanates were found to be the major carriers of the observed activity. Although there was a relatively low differential effect of the plant metabolites on transformed and non-transformed cell lines, one can argue that the noted strong cytotoxicity provides first evidence that could explain the long forgotten use of this

[Effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in the guinea pig].

PubMed

Feng, B; Jiang, S; Yang, W; Han, D; Zhang, S

2001-02-01

To define the effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in guinea pigs. The animals involved in the study were exposed to 8 Hz infrasound at 135dB SPL for 90 minutes in a reverberant chamber. The sinusoidal pendular test (SPT), auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) were respectively detected pre-exposure and at 0(within 2 hrs), 2 and 5 day after exposure. The ultrastructures of the inner ear were observed by scanning electron microscopy. The slow-phase velocity and the frequency of the vestibular nystagmus elicited by sinusoidal pendular test (SPT) declined slightly following infrasound exposure, but the changes were not significant (P > 0.05). No differences in the ABR thresholds, the latencies and the interval peak latencies of I, III, V waves were found between the normal and the experimental groups, and among experimental groups. The amplitudes of DPOAE at any frequency declined remarkably in all experimental groups. The ultrastructures of the inner ear were damaged to different extent. Infrasound could transiently depress the excitability of the vestibular end-organs, decrease the function of OHC in the organ of Corti and cause damage to the inner ear of guinea pigs.

The effect of heating temperature on cytotoxicity and α-mangostin yield: Mangosteen pericarp juice and mangosteen extract

NASA Astrophysics Data System (ADS)

Mulia, Kamarza; Hasanah, Fitria; Krisanti, Elsa A.

2018-03-01

The pericarp of mangosteen (Garcinia mangostana L.) contains bioactive xanthones, with α-mangostin being the major component, has been known to possess antitumor, antiviral, and other pharmacological activities. In this study, the effect of elevated temperature during the preparation step of fresh mangosteen pericarp juice and mangosteen extract, on their α-mangostin yield and cytotoxicities was investigated. The cytotoxicity activity of fresh juice and mangosteen extract was investigated using the brine shrimp test. Heating the fresh pericarp mangosteen in water at 65°C for 30 minutes prior to blending produced a juice with higher α-mangostin yield and cytotoxicity compared to the traditional way of blending the juice at room temperature. Increasing α-mangostin yield of 9%-w/w due to heating was also observed when mangosteen extract was heated at 65°C, consistent with the increased cytotoxicity in terms of LC50 value. It is concluded that the effect of temperature on α-mangostin yield was in line with the temperature effect on cytotoxicity activity in all samples of pericarp juice and mangosteen extract in ethyl acetate fraction.

Effects of estrogen replacement therapy on the myelin sheath ultrastructure of myelinated fibers in the white matter of middle-aged ovariectomized rats.

PubMed

He, Qi; Luo, Yanmin; Lv, Fulin; Xiao, Qian; Chao, Fenglei; Qiu, Xuan; Zhang, Lei; Gao, Yuan; Xiu, Yun; Huang, Chunxia; Tang, Yong

2018-04-01

The effects of estrogen replacement therapy (ORT) on white matter and the myelin sheath ultrastructure in the white matter of middle-aged ovariectomized (OVX) rats were investigated in this study. Middle-aged rats were ovariectomized and divided into a placebo replacement (OVX + O) group and an estrogen replacement (OVX + E) group. Then, the Morris water maze, electron microscope techniques, and stereological methods were used to investigate the effects of ORT on spatial learning capacity, white matter volume and the myelin sheath ultrastructure in the white matter. We found that the spatial learning capacity of the OVX + E rats was significantly improved compared with that of the OVX + O rats. When compared with that of OVX + O rats, the total volume of the myelin sheaths in the white matter of the OVX + E rats was significantly increased by 27%, and the difference between the outer perimeter and inner perimeter of the myelin sheaths of the white matter in the OVX + E rats increased significantly by 12.6%. The myelinated fibers with mean diameters of 1.2-1.4 μm were significantly longer (46.1%) in the OVX + E rats; the difference between the mean diameter of myelinated fibers and the mean diameter of axons (0-0.4 μm) was significantly increased by 21.6% in the OVX + E rats. These results suggested that ORT had positive protective effects on the spatial learning ability and on the myelin sheath ultrastructure in the white matter of middle-aged OVX rats. © 2017 Wiley Periodicals, Inc.

Effect of Toxoplasma lysate antigen (TLA) on feline cytotoxicity against FeLV positive lymphoma cells.

PubMed

Yang, M P; Goitsuka, R; Ono, K; Suzuki, N; Hasegawa, A

1990-08-01

The cytotoxic activities of feline spleen cells treated with Toxoplasma lysate antigen (TLA) were assayed against feline leukemia virus (FeLV)-producing lymphoma. FL74 cells, and xenogeneic target lymphoma, mouse YAC-1 cells. The TLA treatments were performed in vivo alone, in vitro alone, and in vivo plus in vitro, respectively. In vivo plus in vitro treatments with TLA induced a marked augmentation in cytotoxic activity of spleen cells to FL74 cells. The treatment with TLA in vivo alone showed an enhancement of cytotoxic activity but in vitro alone did not. The cytotoxic effects of TLA-treated spleen cells obtained from the cats which had been previously immunized with live FL74 cells were similar to those of spleen cells from non-immunized cats treated with TLA. However, no increase of cytotoxicity was shown in the response to mouse YAC-1 cells regardless of TLA treatments. These results indicated that the in vivo TLA treatment augmented the cytotoxicity of feline spleen cells against FeLV-producing lymphoma cell.

Signet-ring cell lymphoma of T-cell origin. An immunocytochemical and ultrastructural study relating giant vacuole formation to cytoplasmic sequestration of surface membrane.

PubMed

Grogan, T M; Richter, L C; Payne, C M; Rangel, C S

1985-09-01

In contrast to previous accounts of signet-ring lymphoma as a B-cell neoplasm, we report a case of signet-ring, large-cell lymphoma of T-cell lineage. Immunologic and ultrastructural studies were performed on a subcutaneous mass noted initially, as well as on an enlarged lymph node that developed later, in a 69-year-old man. Immunologic assessment indicated strong expression of T-helper antigen (Leu 3a + b), universal T-antigens (Leu 1, 5), and Ia. There was an absence of T-suppressor/cytotoxic antigen (Leu 2a), universal T-antigens (Leu 4, 9), and immunoglobulin light and heavy chains. Collectively, these findings indicate a mature T-cell lymphoma of T-helper type in an activated (Ia+) state. In contrast to previous reports of T-cell and Ia occurring solely as surface antigens, we demonstrated pools of cytoplasmic Leu 1, 3, 5 and Ia that displaced the nucleus. The ultrastructure of the giant cytoplasmic vacuoles was identical to the microvesicle-containing vacuoles reported in signet-ring cell lymphomas of B-cell lineage. In our case of T-cell lineage, we found substantial evidence of endocytosis by the neoplastic cells and numerous giant multivesicular bodies. The pools of cytoplasmic T and Ia antigens may result from abnormal internalization of surface T-antigens or the sequestration of T-antigen-containing Golgi-derived vesicles. Our combined immunologic and ultrastructural findings suggest that aberrant membrane recycling may be the common denominator of signet-ring formation in both B- and T-cell signet-ring lymphomas.

Ultrastructural Analysis of In Vivo Hypoglycemiant Effect of Two Polyoxometalates in Rats with Streptozotocin-Induced Diabetes.

PubMed

Bâlici, Ştefana; Wankeu-Nya, Modeste; Rusu, Dan; Nicula, Gheorghe Z; Rusu, Mariana; Florea, Adrian; Matei, Horea

2015-10-01

Two polyoxometalates (POMs), synthesized through a self-assembling method, were used in the treatment of streptozotocin (STZ)-induced diabetic rats. One of these nanocompounds [tris(vanadyl)-substituted tungsto-antimonate(III)-anions—POM1] was previously described in the literature, whereas the second [tris-butyltin-21-tungsto-9-antimonate(III)-anions—POM2], was prepared by us based on our original formula. In rats with STZ-induced diabetes treated with POMs (up to a cumulative dose of 4 mg/kg bodyweight at the end of the treatments), statistically significant reduced levels of blood glucose were measured after 3 weeks, as compared with the diabetic control groups (DCGs). Ultrastructural analysis of pancreatic β-cells (including the mean diameter of secretory vesicles and of their insulin granules) in the treated diabetic rats proved the POMs contribute to limitation of cellular degeneration triggered by STZ, as well as to the presence of increased amounts of insulin-containing vesicles as compared with the DCG. The two POMs also showed hepatoprotective properties when ultrastructural aspects of hepatocytes in the experimental groups of rats were studied. Based on our in vivo studies, we concluded that the two POMs tested achieved hypoglycemiant effects by preventing STZ-triggered apoptosis of pancreatic β-cells and stimulation of insulin synthesis.

Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats.

PubMed

Center, S A; Guida, L; Zanelli, M J; Dougherty, E; Cummings, J; King, J

1993-05-01

In this study, we compared hepatic ultrastructure in healthy cats, in cats with severe hepatic lipidosis, and in cats with experimentally induced, chronic, extrahepatic bile duct occlusion. Ultrastructural features unique to the lipidosis syndrome included an apparent reduction in number of peroxisomes and alteration in their morphologic features. The quantity of endoplasmic reticulum, Golgi complexes, and lysosomes was subjectively reduced, and paucity of cytosolic glycogen was observed. Bile canaliculi appeared collapsed because of cytosolic distention with lipid. Mitochondria were reduced in number and were markedly pleomorphic. Cristae assumed a variety of shapes, lengths, and orientations. Ultrastructural features of bile duct occlusion were similar to those described in other species and differed from those in cats with hepatic lipidosis.

Cytotoxic effects of residual chemicals from polymeric biomaterials for artificial soft intraocular lenses.

PubMed

Chirila, T V; Walker, L N; Constable, I J; Thompson, D E; Barrett, G D

1991-03-01

Development of improved hydrogels for soft intraocular lenses, based on 2-hydroxyethyl methacrylate monomer, requires the use of various other monomers and polymerization additives which have potential ocular toxicity. Three monomers, 2-hydroxyethyl methacrylate, methyl methacrylate, and 2-ethoxyethyl methacrylate, as well as two common inhibitors, hydroquinone and 4-methoxyphenol, were subjected to in vitro cytotoxicity assays as aqueous solutions at different concentrations. A new polymerization initiator, 2,2'-azo-bis-(2,4-dimethyl valeronitrile), was thermally decomposed in water at different concentrations and the products were also assayed for cytotoxicity. Assays were based on incubation with human choroidal fibroblasts. Cell death was evaluated by trypan blue dye exclusion, DNA synthesis inhibition, and lactate dehydrogenase tests. While methyl methacrylate and 2-ethoxyethyl methacrylate were found nontoxic, the other chemicals displayed high cytotoxicity. However, when extracts of synthesized poly(2-hydroxyethyl methacrylate) specimens, differentially treated after polymerization, were subjected to the same assays it was found that toxicity from residual 2-hydroxyethyl methacrylate monomer was lost during steam sterilization and storage in water because of the removal of the monomer through aqueous washing. The lack of toxicity in these specimens suggests that residual contents of inhibitor and initiator are too low to cause toxic effects on choroidal fibroblasts. It is concluded that hydrogels have low cytotoxic effects in vitro.

[Myocardial ultrastructural changes in rats following different levels of acute +Gz exposure].

PubMed

Zheng, Jun; Liu, Cheng-gang; Ren, Li; Xiao, Xiao-guang; Xu, Shu-xuan; Wang, Ping; Ji, Gui-ying

2004-06-01

To observe the effects of different levels of acute +Gz exposure on myocardial ultrastructure of rats and provide experimental basis for further development of anti-G measures. Twenty male Wistar rats were randomly divided into 4 groups (n=5): normal control group, +20 Gz group, +10 Gz group and +5 Gz group. Profile of the centrifuge +Gz exposure was trapezoidal, in which +20 Gz lasted for 30 s, +10 Gz for 1.5 min. +5 Gz exposure was repeated for 3 times with 30 min interval and each for 1.5 min. Myocardial tissue of left ventricle was sampled for transmission electron microscopy 5 h after exposure. +20 Gz and +10 Gz exposure caused obvious edema of myocardial and endothelial cells, myofibril disorder and injuries of mitochondria and nucleus. Breaks of myocardial fiber, formation of contraction bands and rupture of mitochondria were also observed in +20 Gz group. In +5 Gz group, there was still slight edema of myocardial and endothelial cells, while organic changes of myocardial ultrastructure were not observed. High +Gz exposure can cause myocardial ultrastructural injury in rats. Slight reversible injured response can also be observed in myocardial cell after repeated moderate level of +Gz exposure. This indicates that attention should be paid to the study of the effect of high +Gz on heart in pilots.

Primary cilia in gastric Gastrointestinal Stromal Tumours (GISTs): an ultrastructural study

PubMed Central

Castiella, Tomás; Muñoz, Guillermo; Luesma, María José; Santander, Sonia; Soriano, Mario; Junquera, Concepción

2013-01-01

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal (non-epithelial) neoplasms of the human gastrointestinal (GI) tract. They are thought to derive from interstitial cells of Cajal (ICCs) or an ICC progenitor based on immunophenotypical and ultrastructural similarities. Because ICCs show primary cilium, our hypothesis is based on the possibility that some of these neoplastic cells could also present it. To determine this, an exhaustive ultrastructural study has been developed on four gastric GISTs. Previous studies had demonstrated considerable variability in tumour cells with two dominating phenotypes, spindly and epithelioid. In addition to these two types, we have found another cell type reminiscent of adult ICCs with a voluminous nucleus surrounded by narrow perinuclear cytoplasm with long slender cytoplasmic processes. We have also noted the presence of small undifferentiated cells. In this study, we report for the first time the presence of primary cilia (PCs) in spindle and epithelioid tumour cells, an ultrastructural feature we consider of special interest that has hitherto been ignored in the literature dealing with the ultrastructure of GISTs. We also point out the frequent occurrence of multivesicular bodies (MVBs). The ultrastructural findings described in gastric GISTs in this study appear to be relevant considering the critical roles played by PCs and MVBs recently demonstrated in tumourigenic processes. PMID:23672577

Evaluation of anticancer effects and enhanced doxorubicin cytotoxicity of xanthine derivatives using canine hemangiosarcoma cell lines.

PubMed

Motegi, Tomoki; Katayama, Masaaki; Uzuka, Yuji; Okamura, Yasuhiko

2013-10-01

Methylxanthine derivatives increase cAMP and are known to have diuretic, cardiac, and central nervous system stimulatory effects. Moreover, caffeine inhibits the development of tumors induced by various carcinogens. The aim of this work was to elucidate the anticancer effects on apoptosis of xanthine derivatives alone and with doxorubicin in canine hemangiosarcoma cells. Xanthine derivatives with or without doxorubicin were administered to cells, and the effects were investigated by measuring tumor cell proliferation, cell death (cytotoxicity) induction, and apoptosis by the expression of annexin V or caspase 3/7. Both caffeine and theophylline induced apoptosis, and the treated cells expressed annexin V and caspase 3/7. Both drugs enhanced doxorubicin-induced cytotoxicity; however, hypoxanthine showed no effect. These results indicate that theophylline is similar to caffeine; both drugs may enhance doxorubicin-induced cytotoxicity by inhibiting ATM/ATR kinases. Our data suggest that caffeine and theophylline have anticancer effects and can improve the treatment effect in canine hemangiosarcoma patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

Anti-inflammatory, anti-cholinergic and cytotoxic effects of Sida rhombifolia.

PubMed

Mah, Siau Hui; Teh, Soek Sin; Ee, Gwendoline Cheng Lian

2017-12-01

Sida (Malvaceae) has been used as a traditional remedy for the treatment of diarrhoea, malarial, gastrointestinal dysentery, fevers, asthma and inflammation. This study evaluates the anti-inflammatory, cytotoxic and anti-cholinergic activities of Sida rhombifolia Linn. whole plant for the first time. S. rhombifolia whole plant was extracted by n-hexane, ethyl acetate and methanol using Soxhlet apparatus. The plant extracts were evaluated for their antioxidant (DPPH, FIC and FRAP), anti-inflammatory (NO and protein denaturation inhibitions), cytotoxic (MTT) and anti-cholinesterase (AChE) properties in a range of concentrations to obtain IC 50 values. GC-MS analysis was carried out on the n-hexane extract. The ethyl acetate extract exhibited the most significant antioxidant activities by scavenging DPPH radicals and ferrous ions with EC 50 of 380.5 and 263.4 μg/mL, respectively. In contrast, the n-hexane extract showed the strongest anti-inflammatory activity with IC 50 of 52.16 and 146.03 μg/mL for NO and protein denaturation inhibition assays, respectively. The same extract also revealed the strongest effects in anti-cholinesterase and cytotoxic tests at the concentration of 100 μg/mL, AChE enzyme inhibition was 58.55% and human cancer cells, SNU-1 and Hep G2 inhibition was 68.52% and 47.82%, respectively. The phytochemicals present in the n-hexane extract are palmitic acid, linoleic acid and γ-sitosterol. The present study revealed that the n-hexane extract possessed relatively high pharmacological activities in anti-inflammation, cytotoxicity and anti-cholinesterase assays. Thus, further work on the detail mechanism of the bioactive phytochemicals which contribute to the biological properties are strongly recommended.

Evaluation of ultrastructural hepatic response to environmental toxicants in wild cotton rats (Sigmodon hispidus)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elangbam, C.S.; Qualls, C.W.; Confer, A.W.

1991-08-01

Hepatic lobules are composed of hepatocytes organized in three microcirculatory zones (periportal, midzonal, and centrilobular). The hepatocytes in each of these zones contain enzymes which are involved in various biochemical reactions. The predominant location of the mixed-function oxidation system in the liver lobule is the centrilobular zone. Ultrastructural changes in the hepatocytes not only correlate with biochemical events of detoxification but also with toxic effects of a parent compound or its metabolites. The objectives of this study was to characterize the ultrastructural alterations in the liver of wild cotton rats (Sigmodon hispidus) following exposure to polychlorinated biphenyls (PCB) contaminated habitat.

Cytotoxicity and anti-Leishmania amazonensis activity of Citrus sinensis leaf extracts.

PubMed

Garcia, Andreza R; Amaral, Ana Claudia F; Azevedo, Mariana M B; Corte-Real, Suzana; Lopes, Rosana C; Alviano, Celuta S; Pinheiro, Anderson S; Vermelho, Alane B; Rodrigues, Igor A

2017-12-01

Leishmania amazonensis is the main agent of diffuse cutaneous leishmaniasis, a disease characterized by lesional polymorphism and the commitment of skin surface. Previous reports demonstrated that the Citrus genus possess antimicrobial activity. This study evaluated the anti-L. amazonensis activity of Citrus sinensis (L.) Osbeck (Rutaceae) extracts. Citrus sinensis dried leaves were subjected to maceration with hexane (CH), ethyl acetate (CEA), dichloromethane/ethanol (CD/Et - 1:1) or ethanol/water (CEt/W - 7:3). Leishmania amazonensis promastigotes were treated with C. sinensis extracts (1-525 μg/mL) for 120 h at 27 °C. Ultrastructure alterations of treated parasites were evaluated by transmission electron microscopy. Cytotoxicity of the extracts was assessed on RAW 264.7 and J774.G8 macrophages after 48-h treatment at 37 °C using the tetrazolium assay. In addition, Leishmania-infected macrophages were treated with CH and CD/Et (10-80 μg/mL). CH, CD/Et and CEA displayed antileishmanial activity with 50% inhibitory activity (IC 50 ) of 25.91 ± 4.87, 54.23 ± 3.78 and 62.74 ± 5.04 μg/mL, respectively. Parasites treated with CD/Et (131.2 μg/mL) presented severe alterations including mitochondrial swelling, lipid body formation and intense cytoplasmic vacuolization. CH and CD/Et demonstrated cytotoxic effects similar to that of amphotericin B in the anti-amastigote assays (SI of 2.16, 1.98 and 1.35, respectively). Triterpene amyrins were the main substances in CH and CD/Et extracts. In addition, 80 μg/mL of CD/Et reduced the number of intracellular amastigotes and the percentage of infected macrophages in 63% and 36%, respectively. The results presented here highlight C. sinensis as a promising source of antileishmanial agents.

Synergistic cytotoxic effects of ions released by zinc-aluminum bronze and the metallic salts on osteoblastic cells.

PubMed

Grillo, Claudia A; Morales, María L; Mirífico, María V; Fernández Lorenzo de Mele, Mónica A

2013-07-01

The use of copper-based alloys for fixed dental crowns and bridges is increasingly widespread in several countries. The aim of this work is to study the dissolution of a zinc-aluminum-bronze and the cytotoxic effects of the ions released on UMR-106 osteoblastic cell line. Two sources of ions were used: (1) ions released by the metal alloy immersed in the cell culture and (2) salts of the metal ions. Conventional electrochemical techniques, atomic absorption spectroscopy [to obtain the average concentration of ions (AC) in solution], and energy dispersive X-ray (EDX) spectroscopy analysis were used to study the corrosion process. Corrosion tests revealed a strong influence of the composition of the electrolyte medium and the immersion time on the electrochemical response. The cytotoxicity was evaluated with (a) individual ions, (b) combinations of two ions, and (c) the mixture of all the ions released by a metal disc of the alloy. Importantly, synergistic cytotoxic effects were found when Al-Zn ion combinations were used at concentration levels lower than the cytotoxic threshold values of the individual ions. Cytotoxic effects in cells in the vicinity of the metal disc were also found. These results were interpreted considering synergistic effects and a diffusion controlled mechanism that yields to concentration levels, in the metal surroundings, several times higher than the measured AC value. Copyright © 2013 Wiley Periodicals, Inc.

Effects of folic acid deficiency and MTHFRC677T polymorphisms on cytotoxicity in human peripheral blood lymphocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu Xiayu; Liang Ziqing; Zou Tianning

2009-02-13

Apoptosis (APO) and necrosis (NEC) are two different types of cell death occurring in response to cellular stress factors. Cells with DNA damage may undergo APO or NEC. Folate is an essential micronutrient associated with DNA synthesis, repair and methylation. Methylenetetrahydrofolate reductase (MTHFR) regulates intracellular folate metabolism. Folate deficiency and MTHFR C677T polymorphisms have been shown to be related to DNA damage. To verify the cytotoxic effects of folate deficiency on cells with different MTHFR C677T genotypes, 15 human peripheral lymphocyte cases with different MTHFR C677T genotypes were cultured in folic acid (FA)-deficient and -sufficient media for 9 days. Cytotoxicitymore » was quantified using the frequencies of APO and NEC as endpoints, the nuclear division index (NDI), and the number of viable cells (NVC). These results showed that FA is an important factor in reducing cytotoxicity and increasing cell proliferation. Lymphocytes with the TT genotype proliferated easily under stress and exhibited different responses to FA deficiency than lymphocytes with the CC and CT genotypes. A TT individual may accumulate more cytotoxicity under cytotoxic stress, suggesting that the effects of FA deficiency on cytotoxicity are greater than the effects in individuals with the other MTHFR C677T variants.« less

The Key Role of Mitochondrial Apoptotic Pathway in the Cytotoxic Effect of Mushroom Extracts on Cancer Cells.

PubMed

Han, Mei; Ling, Ming-Tat; Chen, Jiezhong

2015-01-01

Mushroom extracts have been extensively studied for their medicinal effects. They can stimulate immune responses and thus have been explored in cancer treatment. Recently, it has also been shown that some mushroom extracts can produce direct cytotoxic effect on cancer cells. In this review, we summarize the cytotoxic effect of mushroom extracts in cancer treatment revealed by both in vitro and in vivo studies. We also summarize the current understanding of the mechanisms associated with such an effect with an emphasis on the mitochondrial apoptotic pathway. The recent finding that mushroom extracts have direct cytotoxic effects supplements their known immune stimulating effects. Thus, novel anticancer agents based on new findings from mushroom extracts may soon be added to the present pool of anticancer drugs. Specifically, we propose that nanodelivery of the bioactive compounds of mushroom extracts to mitochondria will further increase their potential treatment efficacy.

Cytotoxic Effects of Re-Activated Lunar Dust Stimulant on Human Lung Cells

NASA Technical Reports Server (NTRS)

Upadhyaya, Krishna

2009-01-01

Lunar dust has been of significant concern due to various problems observed on the Apollo missions. Reports from astronauts have shown that the dust may have caused eye and nasal irritation as well as possible hay fever like symptoms. As NASA hopes to go to the Moon within the next few years, we hope to understand the possible toxic effects the dust might have. In these studies, we are looking at the effect of "re-activated" lunar dust stimulant on human bronchial cells. A simple grinding analog as a method of simulating micrometeorite crushing on the moon is used to "activate" the dust stimulant, i.e. capable of producing hydroxyl radicals. These radicals could then interact with human cells and may lead to a loss in membrane integrity and cell death. (Castranova, 1994) Cells are exposed to the dust for 6 and 24 hour intervals to assess cytotoxicity. Cytotoxicity is measured by looking at the production of inflammatory cytokines. Cells are exposed to ground and unground stimulant and compared to cytokine production from cells exposed to quartz which have a known toxicity. Here we look at the cytotoxicity of the lunar dust stimulant relative to quartz by measuring the production of inflammatory cytokines.

Effect of chlorhexidine digluconate on different cell types: a molecular and ultrastructural investigation.

PubMed

Giannelli, M; Chellini, F; Margheri, M; Tonelli, P; Tani, A

2008-03-01

Although several studies have shown that chlorhexidine digluconate (CHX) has bactericidal activity against periodontal pathogens and exerts toxic effects on periodontal tissues, few have been directed to evaluate the mechanisms underlying its adverse effects on these tissues. Therefore, the aim of the present study was to investigate the in vitro cytotoxicity of CHX on cells that could represent common targets for its action in the surgical procedures for the treatment of periodontitis and peri-implantitis and to elucidate its mechanisms of action. Osteoblastic, endothelial and fibroblastic cell lines were exposed to various concentrations of CHX for different times and assayed for cell viability and cell death. Also analysis of mitochondrial membrane potential, intracellular Ca2+ mobilization and reactive oxygen species (ROS) generation were done in parallel, to correlate CHX-induced cell damage with alterations in key parameters of cell homeostasis. CHX affected cell viability in a dose and time-dependent manners, particularly in osteoblasts. Its toxic effect consisted in the induction of apoptotic and autophagic/necrotic cell deaths and involved disturbance of mitochondrial function, intracellular Ca2+ increase and oxidative stress. These data suggest that CHX is highly cytotoxic in vitro and invite to a more cautioned use of the antiseptic in the oral surgical procedures.

Effect of differential photoperiod treatment on Leydig cell ultrastructure in the bank vole (Clethrionomys glareolus, S.).

PubMed

Tähkä, K M

1988-08-01

Juvenile bank voles (18-22 days of age) born and reared in a stimulatory long photoperiod (18L:6D, lights on 0600-2400 hr) were subjected either to a long photoperiod (18L:6D, Group L) or to a short photoperiod (6L:18D, lights on 0800-1400 hr, Group S) for 6 to 8 weeks whereafter the animals were killed by decapitation. Possible photoperiod-induced changes in Leydig cell ultrastructure were studied by conventional transmission electron microscopy and stereological methods. Striking differences in Leydig cell ultrastructure between the experimental groups were encountered. Light deprivation induced a marked decrease in the cytoplasmic and nuclear volume as well as in the amounts of smooth endoplasmic reticulum (SER), rough endoplasmic reticulum, mitochondria, and lipid inclusions in the Leydig cells. The number of myelin bodies and dense bodies seemed to be somewhat higher in the regressive Group S Leydig cells. These results are in good agreement with our previous histological and biochemical studies on the effects of photoperiod on Leydig cell function and suggest that in the bank vole the volume of mitochondria and SER in particular correlates positively with the steroidogenic capacity (the activity of C20 alpha 22-C27 desmolase, 17 alpha-hydroxylase, and C17-20 lyase in particular) in the Leydig cell.

In vitro and in vivo antithrombotic and cytotoxicity effects of ferulic acid.

PubMed

Choi, Jun-Hui; Park, Jong-Kook; Kim, Ki-Man; Lee, Hyo-Jeong; Kim, Seung

2018-01-01

We discovered recently in vitro and in vivo antithrombotic and cytotoxicity effects of ferulic acid. The cytotoxicity assays showed that ferulic acid (∼300 μg/mL) did not cause any significant toxicity on three cell lines, platelets, leukocytes, and erythrocytes. In vitro assays showed inhibitory effects of ferulic acid on thrombin (THR)- or collagen/epinephrine-stimulated platelet activation by inhibiting platelet aggregation, and decreasing clot retraction activity. The in vitro effect of ferulic acid on THR-stimulated platelet activation was proved by the decrease in the secretion of serotonin from the platelets. The anticoagulant effects of ferulic acid were confirmed by the prolongation of the intrinsic or/and extrinsic pathways and the delay of recalcification time in plasma coagulation. Ferulic acid had antithrombotic effect in acute thromboembolism model in vivo, and decreased the expression of α IIb β 3 /FIB and phosphorylation of AKT in THR-stimulated platelet activation in vivo, and their antithrombotic efficacies hold promise for therapeutic targeting in our ongoing studies. © 2017 Wiley Periodicals, Inc.

Nematodes ultrastructure: complex systems and processes.

PubMed

Basyoni, Maha M A; Rizk, Enas M A

2016-12-01

Nematode worms are among the most ubiquitous organisms on earth. They include free-living forms as well as parasites of plants, insects, humans and other animals. Recently, there has been an explosion of interest in nematode biology, including the area of nematode ultrastructure. Nematodes are round with a body cavity. They have one way guts with a mouth at one end and an anus at the other. They have a pseudocoelom that is lined on one side with mesoderm and on the other side with endoderm. It appears that the cuticle is a very complex and evolutionarily plastic feature with important functions involving protection, body movement and maintaining shape. They only have longitudinal muscles so; they seem to thrash back and forth. While nematodes have digestive, reproductive, nervous and excretory systems, they do not have discrete circulatory or respiratory systems. Nematodes use chemosensory and mechanosensory neurons embedded in the cuticle to orient and respond to a wide range of environmental stimuli. Adults are made up of roughly 1000 somatic cells and hundreds of those cells are typically associated with the reproductive systems. Nematodes ultrastructure seeks to provide studies which enable their use as models for diverse biological processes including; human diseases, immunity, host-parasitic interactions and the expression of phylogenomics. The latter has, however, not been brought into a single inclusive entity. Consequently, in the current review we tried to provide a comprehensive approach to the current knowledge available for nematodes ultrastructures.

Toxic effects of inhaled manganese on the olfactory bulb: an ultrastructural approach in mice.

PubMed

Colin-Barenque, L; Souza-Gallardo, L M; Fortoul, T I

2011-01-01

Olfactory dysfunction is a common symptom reported by patients with neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Despite the knowledge gathered about the pathology of these diseases, little information has been generated regarding the ultrastructure modifications of the granule cells that regulate the information for odor identification. Swollen organelles and nuclear invaginations identified the exposed mice. Necrosis was evidenced at 4th week of exposure, whereas apoptosis arose at 8th week of exposure. A ruffled electron-dense membrane changes were also found. The changes observed could be explained by the reactive oxygen species generated by manganese and its effects on the membrane's structure and on the cytoskeleton's function. This study contributes to correlate metal air pollution and neurodegenerative changes with olfactory affection.

Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Li-Wu; Wu, Qiangen; Green, Bridgett

2012-07-15

Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCSmore » (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.« less

Evaluation of cytotoxicity of different tobacco product preparations.

PubMed

Arimilli, Subhashini; Damratoski, Brad E; Bombick, Betsy; Borgerding, Michael F; Prasad, G L

2012-12-01

Acute exposure to cigarette smoke or its components triggers diverse cellular effects, including cytotoxicity. However, available data regarding the potential cytotoxic effects of smokeless tobacco (ST) extracts lack consensus. Here, we investigated the relative biological effects of 2S3 reference ST, and whether ST elicits differential cellular/molecular responses compared to combustible tobacco product preparations (TPPs) prepared from 3R4F cigarettes. Total particulate matter (TPM) and whole smoke conditioned medium (WS-CM) were employed as combustible TPPs, while the ST extract was used as non-combustible TPP. HL60, THP1 cells and human PBMCs were used to examine the effects of TPPs in short-term cell culture. Corresponding EC(50) values, normalized for nicotine content of the TPPs, suggest that combustible TPPs induced higher cytotoxicity as follows: WS-CM TPM ≥ ≫ST extract>nicotine. While all three TPPs induced detectable levels of DNA damage and IL8 secretion, the combustible TPPs were significantly more potent than the ST preparation. The major PBMC subsets showed differential cytotoxicity to combustible TPPs as follows: CD4>CD8>monocytes>NK cells. These findings suggest that, relative cytotoxic and other cell biological effects of TPPs are dose-dependent, and that ST extract is the least cytotoxic TPP tested in this study. Copyright © 2012 Elsevier Inc. All rights reserved.

Antioxidative, antimicrobial and cytotoxic effects of the phenolics of Leea indica leaf extract

PubMed Central

Rahman, Md. Atiar; Imran, Talha bin; Islam, Shahidul

2012-01-01

This study investigated the phytochemical, antioxidative, antimicrobial and cytotoxic effects of Leea indica leaf ethanol extract. Phytochemical values namely total phenolic and flavonoid contents, total antioxidant capacity, DPPH radical scavenging effect, FeCl3 reducing power, DMSO superoxide scavenging effect and Iron chelating effects were studied by established methods. Antibacterial, antifungal and cytotoxic effects were screened by disk diffusion technique, food poison technique and brine shrimp bioassay, respectively. Results showed the total phenolic content 24.00 ± 0.81 g GAE/100 g, total flavonoid content 194.68 ± 2.43 g quercetin/100 g and total antioxidant capacity 106.61 ± 1.84 g AA/100 g dry extract. Significant (P < 0.05) IC50 values compared to respective standards were recorded in DPPH radical scavenging (139.83 ± 1.40 μg/ml), FeCl3 reduction (16.48 ± 0.64 μg/ml), DMSO superoxide scavenging (676.08 ± 5.80 μg/ml) and Iron chelating (519.33 ± 16.96 μg/ml) methods. In antibacterial screening, the extract showed significant (P < 0.05) zone of inhibitions compared to positive controls Ampicillin and Tetracycline against Gram positive Bacillus subtilis, Bacillus cereus, Bacillus megaterium, and Staphylococcus aureus and Gram negative Salmonella typhi, Salmonella paratyphi, Pseudomonas aeroginosa, Shigella dysenteriae, Vibrio cholerae, and Escherichia coli. Significant minimum inhibitory concentrations compared to tetracycline were obtained against the above organisms. In antifungal assay, the extract inhibited the growth of Aspergillus flavus, Candida albicans and Fusarium equisetii by 38.09 ± 0.59, 22.58 ± 2.22, and 22.58 ± 2.22%, respectively. The extract showed a significant LC50 value compared to vincristine sulfate in cytotoxic assay. The results evidenced the potential antioxidative, antimicrobial and cytotoxic capacities of Leea inidica leaf extract to be processed for pharmaceutical use. PMID

Cytotoxic Effects of Temozolomide and Radiation are Additive- and Schedule-Dependent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chalmers, Anthony J., E-mail: a.j.chalmers@sussex.ac.u; Genome Damage and Stability Centre, University of Sussex, Falmer; Ruff, Elliot M.

2009-12-01

Purpose: Despite aggressive therapy comprising radical radiation and temozolomide (TMZ) chemotherapy, the prognosis for patients with glioblastoma multiforme (GBM) remains poor, particularly if tumors express O{sup 6}-methylguanine-DNA-methyltransferase (MGMT). The interactions between radiation and TMZ remain unclear and have important implications for scheduling and for developing strategies to improve outcomes. Methods and Materials: Factors determining the effects of combination therapy on clonogenic survival, cell-cycle checkpoint signaling and DNA repair were investigated in four human glioma cell lines (T98G, U373-MG, UVW, U87-MG). Results: Combining TMZ and radiation yielded additive cytotoxicity, but only when TMZ was delivered 72 h before radiation. Radiosensitization wasmore » not observed. TMZ induced G2/M cell-cycle arrest at 48-72 h, coincident with phosphorylation of Chk1 and Chk2. Additive G2/M arrest and Chk1/Chk2 phosphorylation was only observed when TMZ preceded radiation by 72 h. The ataxia-telangiectasia mutated (ATM) inhibitor KU-55933 increased radiation sensitivity and delayed repair of radiation-induced DNA breaks, but did not influence TMZ effects. The multiple kinase inhibitor caffeine enhanced the cytotoxicity of chemoradiation and exacerbated DNA damage. Conclusions: TMZ is not a radiosensitizing agent but yields additive cytotoxicity in combination with radiation. Our data indicate that TMZ treatment should commence at least 3 days before radiation to achieve maximum benefit. Activation of G2/M checkpoint signaling by TMZ and radiation has a cytoprotective effect that can be overcome by dual inhibition of ATM and ATR. More specific inhibition of checkpoint signaling will be required to increase treatment efficacy without exacerbating toxicity.« less

Physico-chemical properties and cytotoxic effects of sugar-based surfactants: Impact of structural variations.

PubMed

Lu, Biao; Vayssade, Muriel; Miao, Yong; Chagnault, Vincent; Grand, Eric; Wadouachi, Anne; Postel, Denis; Drelich, Audrey; Egles, Christophe; Pezron, Isabelle

2016-09-01

Surfactants derived from the biorefinery process can present interesting surface-active properties, low cytotoxicity, high biocompatibility and biodegradability. They are therefore considered as potential sustainable substitutes to currently used petroleum-based surfactants. To better understand and anticipate their performances, structure-property relationships need to be carefully investigated. For this reason, we applied a multidisciplinary approach to systematically explore the effect of subtle structural variations on both physico-chemical properties and biological effects. Four sugar-based surfactants, each with an eight carbon alkyl chain bound to a glucose or maltose head group by an amide linkage, were synthesized and evaluated together along with two commercially available standard surfactants. Physico-chemical properties including solubility, Krafft point, surface-tension lowering and critical micellar concentration (CMC) in water and biological medium were explored. Cytotoxicity evaluation by measuring proliferation index and metabolic activity against dermal fibroblasts showed that all surfactants studied may induce cell death at low concentrations (below their CMC). Results revealed significant differences in both physico-chemical properties and cytotoxic effects depending on molecule structural features, such as the position of the linkage on the sugar head-group, or the orientation of the amide linkage. Furthermore, the cytotoxic response increased with the reduction of surfactant CMC. This study underscores the relevance of a methodical and multidisciplinary approach that enables the consideration of surfactant solution properties when applied to biological materials. Overall, our results will contribute to a better understanding of the concomitant impact of surfactant structure at physico-chemical and biological levels. Copyright © 2016 Elsevier B.V. All rights reserved.

Meibomian gland studies: histologic and ultrastructural investigations.

PubMed

Jester, J V; Nicolaides, N; Smith, R E

1981-04-01

Heightened interest in meibomian gland dysfunction has prompted us to evaluate the normal morphological and ultrastructural characteristics of the meibomian gland. Histologic analysis of human, primate, steer, and rabbit glands revealed evidence of keratinized epithelium extending throughout the meibomian gland duct. Characteristic ultrastructural features of keratinized epithelium identified in primate and rabbit glands included tonofilaments, keratohyaline granules, lamellar bodies, and keratinized squamous cells. Comparison of the meibomian gland duct to the pilosebaceous canal and the sebaceous duct brought out certain dissimilarities such as (1) the lack of a well-developed stratum granulosum and (2) the absence of lipid inclusions within transitional cells from duct to acini. We postulate that abnormalities of the keratinizing process may be responsible for meibomian gland dysfunction states.

Effect of lipopeptides of antagonistic strains of Bacillus subtilis on the morphology and ultrastructure of the cucurbit fungal pathogen Podosphaera fusca.

PubMed

Romero, D; de Vicente, A; Olmos, J L; Dávila, J C; Pérez-García, A

2007-10-01

To analyse the morphological and ultrastructural effects of lipopeptides of cell-free liquid cultures from the antagonistic Bacillus subtilis strains, UMAF6614 and UMAF6639, on the cucurbit powdery mildew fungus, Podosphaera fusca, conidial germination. Butanolic extracts from cell-free supernatants of B. subtilis cultures were tested for their ability to arrest P. fusca conidial germination using the zucchini cotyledon disc method. Previously, the occurrence of lipopeptide antibiotics fengycin, iturin/bacillomycin and surfactin in the extracts was verified by diverse chromatographic approaches. Conidial germination was strongly reduced by antifungal extracts obtained from liquid cultures of both B. subtilis strains. Scanning electron microscopy analysis showed morphological damage in conidia characterized by the presence of large depressions and loss of turgidness. Transmission electron microscopy analysis revealed severe modifications in the plasma membrane and disorganization of the P. fusca cell cytoplasm. The lipopeptides produced by the two strains of B. subtilis are able to reduce cucurbit powdery mildew disease by arresting conidial germination, which seems to result from the induction of important cytological alterations. We elucidated the mechanisms employed by these antagonistic strains of B. subtilis to suppress cucurbit powdery mildew disease and delineate the ultrastructural damages responsible for their suppressive effect.

Lipoplexes prepared from cationic liposomes and mammalian DNA induce CpG-independent, direct cytotoxic effects in cell cultures and in mice.

PubMed

Khazanov, Elena; Simberg, Dmitri; Barenholz, Yechezkel

2006-08-01

Recent studies demonstrated the cytotoxic activity of bacterial DNA (pDNA) complexed with cationic lipids. This cytotoxicity is related to the ability of pDNA to induce potently the immune system, which is associated with release of inflammatory cytokines. Both activities seem to be related to the nonmethylated CpG sequences present in the pDNA. Here we study the cytotoxic activity of nonbacterial DNA complexed with cationic lipids against various tumor cell lines. Various nucleic acids complexed with cationic liposomes were prepared and their cytotoxic activity was studied in cell cultures and in tumor-bearing mice. Cell uptake of lipoplexes was evaluated, and mechanism of DNA cytotoxic activity was studied. We found that nonbacterial (vertebrate) genomic DNA when complexed with cationic lipids is highly cytotoxic against C-26 and M-109 tumor cells. Cationic lipids alone were not toxic to these cells. The cytotoxic activity does not result from nonspecific acidification of the intracellular milieu, as substitution of DNA by poly-L-glutamate did not result in cytotoxicity, although the level of uptake of anionic charges per cell was similar to that of the nucleic acids, suggesting that this cytotoxic effect is specific to nucleic acids. By studying the nucleic acid fate using confocal microscopy, we found that cytotoxicity correlated with the release of DNA into the cytoplasm following uptake of lipoplexes. Injection of calf thymus DNA-based lipoplexes to mice with peritoneal C-26 metastases resulted in doubling of median survival time and long-term survival in 20% of the tumor-bearing mice. Judging by low levels of IFN-gamma, TNF-alpha and IL-6 in the treated mice, this effect cannot be ascribed to Th-1 inflammation, but rather to a direct cytotoxic effect on the tumor cells. The above data provide a new insight into the mechanisms of lipoplex-mediated antitumor effects in vitro and in vivo and new perspectives in cancer therapy. 2006 John Wiley & Sons, Ltd.

Cytotoxic effects of dimethyl sulphoxide (DMSO) on cochlear organotypic cultures

PubMed Central

Qi, Weidong; Ding, Dalian; Salvi*, Richard J.

2008-01-01

The amphipathic molecule dimethyl sulphoxide (DMSO) is a solvent often used to dissolve compounds applied to the inner ear; however, little is known about its potential cytotoxic side effects. To address this question, we applied 0.1 to 6% DMSO for 24 h to cochlear organotypic cultures from postnatal day 3 rats and examined its cytotoxic effects. DMSO concentrations of 0.1% and 0.25% caused little or no damage. However, concentrations between 0.5 and 6% resulted in stereocilia damage, hair cell swelling and a dose-dependent loss of hair cells. Hair cell damage began in the basal turn of the cochlea and spread towards the apex with increasing concentration. Surprisingly, DMSO-induced damage was greater for inner hair cells than outer hair cell whereas nearby supporting cells were largely unaffected. Most hair cell death was associated with nuclear shrinkage and fragmentation, morphological features consistent with apoptosis. DMSO treatment induced TUNEL positive staining in many hair cells and activated both initiator caspase-9 and caspase-8 and executioner caspase-3; this suggests that apoptosis is initiated by both intrinsic mitochondrial and extrinsic membrane cell death signaling pathways. PMID:18207679

Analysis of the Effects of Cell Stress and Cytotoxicity on In ...

EPA Pesticide Factsheets

Chemical toxicity can arise from disruption of specific biomolecular functions or through more generalized cell stress and cytotoxicity-mediated processes. Here, concentration-dependent responses of 1063 chemicals including pharmaceuticals, natural products, pesticidals, consumer, and industrial chemicals across a diverse battery of 821 in vitro assay endpoints from 7 high-throughput assay technology platforms were analyzed in order to better distinguish between these types of activities. Both cell-based and cell-free assays showed a rapid increase in the frequency of responses at concentrations where cell stress / cytotoxicity responses were observed in cell-based assays. Chemicals that were positive on at least two viability/cytotoxicity assays within the concentration range tested (typically up to 100 M) activated a median of 12% of assay endpoints while those that were not cytotoxic in this concentration range activated 1.3% of the assays endpoints. The results suggest that activity can be broadly divided into: (1) specific biomolecular interactions against one or more targets (e.g., receptors or enzymes) at concentrations below which overt cytotoxicity-associated activity is observed; and (2) activity associated with cell stress or cytotoxicity, which may result from triggering of specific cell stress pathways, chemical reactivity, physico-chemical disruption of proteins or membranes, or broad low-affinity non-covalent interactions. Chemicals showing a g

Suppressive effects of 3-methylcholanthrene on the in vitro antitumor activity of naturally cytotoxic cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lill, P.H.; Gangemi, D.

1986-01-01

Transient suppression of splenic natural killer (NK), natural cytotoxic (NC) and peritoneal macrophage cytotoxicity was observed following a single injection of 3-methylcholanthrene (3-MC) into C3H/HeN mice. Natural killer cell activity was depressed by 30-60% 4-6 d after injection of 1.0 mg 3-MC. Levels of NK reactivity returned to normal 8 d post 3-MC injection, and no suppression of natural killing was seen when tested 6 wk after 3-MC treatment. 3-MC did not affect propionibacterium acnes augmentation of NK cell activity when tested both 6 d and 6 wk after carcinogen injection. The results indicate that the observed suppression of naturallymore » cytotoxic cells may not be important in allowing 3-MC-induced tumors to grow, since suppression is not long-lasting. Therefore, any effect on tumor growth mediated by a suppression of naturally cytotoxic cells would have to be exerted at the earliest stages of tumor development.« less

Effect of steroid hormones on Bufo arenarum oviduct. Ultrastructural study.

PubMed

Medina, Marcela Fátima; Crespo, Claudia Alejandra; Ramos, Inés; Cisint, Susana Beatriz; Fernández, Silvia Nélida

2007-06-01

The endocrine regulation of the mucosa of the oviductal pars convoluta was analyzed by ultrastructural studies demonstrating that ovariectomy, together with a decrease in ovarian steroids circulating levels, caused a marked regression in this portion of Bufo arenarum oviduct. Twenty-five days after ovariectomy, a decrease in the depth of the epithelial and glandular layers was observed due to the notable loss of secretory cells, whose number was clearly smaller than in nonovariectomized females. The remaining secretory cells showed involution signs, with few secretory granules in their cytoplasm, little endoplasmic reticulum near poorly developed Golgi complexes and a large amount of lipid droplets. Cells in an advanced autolysis state were found in the lumen. These characteristics evidence a nonfunctional state of the pars convoluta. Treatment with 5alpha-dihydrotestosterone (DHT) completely reversed the ovariectomy effect, inducing pars convoluta growths and restoring the characteristics of epithelial and glandular secretory cells in the whole pars convoluta, with micrographs similar to the control. These same effects were observed after treatment with estradiol-17beta (E2), progesterone (P) o E(2)+P in the glandular layer of the whole pars convoluta, but only in the epithelial layer of the most anterior region of this duct. In the secretory cells of other segments these treatments induced the formation of granules of high electron density and homogeneous aspect. Each steroid had a particular effect on the pars convoluta. Although E2 and DHT induced the development of the organoids involved in the proteins biosynthesis, P and DHT acted as secretagogues. (c) 2007 Wiley-Liss, Inc.

Antibacterial Effect of Copaifera duckei Dwyer Oleoresin and Its Main Diterpenes against Oral Pathogens and Their Cytotoxic Effect

PubMed Central

Abrão, Fariza; Alves, Jessica A.; Andrade, Gessica; de Oliveira, Pollyanna F.; Ambrósio, Sérgio R.; Veneziani, Rodrigo C. S.; Tavares, Denise C.; Bastos, Jairo K.; Martins, Carlos H. G.

2018-01-01

This study evaluates the antibacterial activity of the Copaifera duckei Dwyer oleoresin and two isolated compounds [eperu-8(20)-15,18-dioic acid and polyalthic acid] against bacteria involved in primary endodontic infections and dental caries and assesses the cytotoxic effect of these substances against a normal cell line. MIC and MBC assays pointed out the most promising metabolites for further studies on bactericidal kinetics, antibiofilm activity, and synergistic antibacterial action. The oleoresin and polyalthic acid but not eperu-8(20)-15,18-dioic provided encouraging MIC and MBC results at concentrations lower than 100 μg mL−1. The oleoresin and polyalthic acid activities depended on the evaluated strain. A bactericidal effect on Lactobacillus casei (ATCC 11578 and clinical isolate) emerged before 8 h of incubation. For all the tested bacteria, the oleoresin and polyalthic acid inhibited biofilm formation by at least 50%. The oleoresin and polyalthic acid gave the best activity against Actinomyces naeslundii (ATCC 19039) and L. casei (ATCC 11578), respectively. The synergistic assays combining the oleoresin or polyalthic acid with chlorhexidine did not afford interesting results. We examined the cytotoxicity of C. duckei oleoresin, eperu-8(20)-15,18-dioic acid, and polyalthic acid against Chinese hamster lung fibroblasts. The oleoresin and polyalthic acid were cytotoxic at concentrations above 78.1 μg mL−1, whereas eperu-8(20)-15,18-dioic displayed cytotoxicity at concentrations above 312.5 μg mL−1. In conclusion, the oleoresin and polyalthic acid are potential sources of antibacterial agents against bacteria involved in primary endodontic infections and dental caries in both the sessile and the planktonic modes at concentrations that do not cause cytotoxicity. PMID:29515530

Effects of water turbulence on variations in cell ultrastructure and metabolism of amino acids in the submersed macrophyte, Elodea nuttallii (Planch.) H. St. John.

PubMed

Atapaththu, K S S; Miyagi, A; Atsuzawa, K; Kaneko, Y; Kawai-Yamada, M; Asaeda, T

2015-09-01

The interactions between macrophytes and water movement are not yet fully understood, and the causes responsible for the metabolic and ultrastructural variations in plant cells as a consequence of turbulence are largely unknown. In the present study, growth, metabolism and ultrastructural changes were evaluated in the aquatic macrophyte Elodea nuttallii, after exposure to turbulence for 30 days. The turbulence was generated with a vertically oscillating horizontal grid. The turbulence reduced plant growth, plasmolysed leaf cells and strengthened cell walls, and plants exposed to turbulence accumulated starch granules in stem chloroplasts. The size of the starch granules increased with the magnitude of the turbulence. Using capillary electrophoresis-mass spectrometry (CE-MS), analysis of the metabolome found metabolite accumulation in response to the turbulence. Asparagine was the dominant amino acid that was concentrated in stressed plants, and organic acids such as citrate, ascorbate, oxalate and γ-amino butyric acid (GABA) also accumulated in response to turbulence. These results indicate that turbulence caused severe stress that affected plant growth, cell ultrastructure and some metabolic functions of E. nuttallii. Our findings offer insights to explain the effects of water movement on the functions of aquatic plants. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

Antibody engineering of a cytotoxic monoclonal antibody 84 against human embryonic stem cells: Investigating the effects of multivalency on cytotoxicity.

PubMed

Klement, Maximilian; Zheng, Jiyun; Liu, Chengcheng; Tan, Heng-Liang; Wong, Victor Vai Tak; Choo, Andre Boon-Hwa; Lee, Dong-Yup; Ow, Dave Siak-Wei

2017-02-10

Antibody fragments have shown targeted specificity to their antigens, but only modest tissue retention times in vivo and in vitro. Multimerization has been used as a protein engineering tool to increase the number of binding units and thereby enhance the efficacy and retention time of antibody fragments. In this work, we explored the effects of valency using a series of self-assembling polypeptides based on the GCN4 leucine zipper multimerization domain fused to a single-chain variable fragment via an antibody upper hinge sequence. Four engineered antibody fragments with a valency from one to four antigen-binding units of a cytotoxic monoclonal antibody 84 against human embryonic stem cells (hESC) were constructed. We hypothesized that higher cytotoxicity would be observed for fragments with increased valency. Flow cytometry analysis revealed that the trimeric and tetrameric engineered antibody fragments resulted in the highest degree of cytotoxicity to the undifferentiated hESC, while the engineered antibody fragments were observed to have improved tissue penetration into cell clusters. Thus, a trade off was made for the trimeric versus tetrameric fragment due to improved tissue penetration. These results have direct implications for antibody-mediated removal of undifferentiated hESC during regenerative medicine and cell therapy. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

Biological effects of a de novo designed myxoma virus peptide analogue: evaluation of cytotoxicity on tumor cells.

PubMed

Istivan, Taghrid S; Pirogova, Elena; Gan, Emily; Almansour, Nahlah M; Coloe, Peter J; Cosic, Irena

2011-01-01

The Resonant Recognition Model (RRM) is a physico-mathematical model that interprets protein sequence linear information using digital signal processing methods. In this study the RRM concept was employed for structure-function analysis of myxoma virus (MV) proteins and the design of a short bioactive therapeutic peptide with MV-like antitumor/cytotoxic activity. The analogue RRM-MV was designed by RRM as a linear 18 aa 2.3 kDa peptide. The biological activity of this computationally designed peptide analogue against cancer and normal cell lines was investigated. The cellular cytotoxicity effects were confirmed by confocal immunofluorescence microscopy, by measuring the levels of cytoplasmic lactate dehydrogenase (LDH) and by Prestoblue cell viability assay for up to 72 hours in peptide treated and non-treated cell cultures. Our results revealed that RRM-MV induced a significant dose and time-dependent cytotoxic effect on murine and human cancer cell lines. Yet, when normal murine cell lines were similarly treated with RRM-MV, no cytotoxic effects were observed. Furthermore, the non-bioactive RRM designed peptide RRM-C produced negligible cytotoxic effects on these cancer and normal cell lines when used at similar concentrations. The presence/absence of phosphorylated Akt activity in B16F0 mouse melanoma cells was assessed to indicate the possible apoptosis signalling pathway that could be affected by the peptide treatment. So far, Akt activity did not seem to be significantly affected by RRM-MV as is the case for the original viral protein. Our findings indicate the successful application of the RRM concept to design a bioactive peptide analogue (RRM-MV) with cytotoxic effects on tumor cells only. This 2.345 kDa peptide analogue to a 49 kDa viral protein may be suitable to be developed as a potential cancer therapeutic. These results also open a new direction to the rational design of therapeutic agents for future cancer treatment.

Biological Effects of a De Novo Designed Myxoma Virus Peptide Analogue: Evaluation of Cytotoxicity on Tumor Cells

PubMed Central

Istivan, Taghrid S.; Pirogova, Elena; Gan, Emily; Almansour, Nahlah M.; Coloe, Peter J.; Cosic, Irena

2011-01-01

Background The Resonant Recognition Model (RRM) is a physico-mathematical model that interprets protein sequence linear information using digital signal processing methods. In this study the RRM concept was employed for structure-function analysis of myxoma virus (MV) proteins and the design of a short bioactive therapeutic peptide with MV-like antitumor/cytotoxic activity. Methodology/Principal Findings The analogue RRM-MV was designed by RRM as a linear 18 aa 2.3 kDa peptide. The biological activity of this computationally designed peptide analogue against cancer and normal cell lines was investigated. The cellular cytotoxicity effects were confirmed by confocal immunofluorescence microscopy, by measuring the levels of cytoplasmic lactate dehydrogenase (LDH) and by Prestoblue cell viability assay for up to 72 hours in peptide treated and non-treated cell cultures. Our results revealed that RRM-MV induced a significant dose and time-dependent cytotoxic effect on murine and human cancer cell lines. Yet, when normal murine cell lines were similarly treated with RRM-MV, no cytotoxic effects were observed. Furthermore, the non-bioactive RRM designed peptide RRM-C produced negligible cytotoxic effects on these cancer and normal cell lines when used at similar concentrations. The presence/absence of phosphorylated Akt activity in B16F0 mouse melanoma cells was assessed to indicate the possible apoptosis signalling pathway that could be affected by the peptide treatment. So far, Akt activity did not seem to be significantly affected by RRM-MV as is the case for the original viral protein. Conclusions/Significance Our findings indicate the successful application of the RRM concept to design a bioactive peptide analogue (RRM-MV) with cytotoxic effects on tumor cells only. This 2.345 kDa peptide analogue to a 49 kDa viral protein may be suitable to be developed as a potential cancer therapeutic. These results also open a new direction to the rational design of therapeutic

Effects of Selected Egyptian Honeys on the Cellular Ultrastructure and the Gene Expression Profile of Escherichia coli.

PubMed

Wasfi, Reham; Elkhatib, Walid F; Khairalla, Ahmed S

2016-01-01

The purpose of this study was to: (i) evaluate the antibacterial activities of three Egyptian honeys collected from different floral sources (namely, citrus, clover, and marjoram) against Escherichia coli; (ii) investigate the effects of these honeys on bacterial ultrastructure; and (iii) assess the anti-virulence potential of these honeys, by examining their impacts on the expression of eight selected genes (involved in biofilm formation, quorum sensing, and stress survival) in the test organism. The minimum inhibitory concentration (MIC) of the honey samples against E. coli ATCC 8739 were assessed by the broth microdilution assay in the presence and absence of catalase enzyme. Impacts of the honeys on the cellular ultrastructure and the expression profiles of the selected genes of E. coli were examined using transmission electron microscopy (TEM) and quantitative real-time polymerase chain reaction (qPCR) analysis, respectively. The susceptibility tests showed promising antibacterial activities of all the tested honeys against E. coli. This was supported by the TEM observations, which revealed "ghost" cells lacking DNA, in addition to cells with increased vacuoles, and/or with irregular shrunken cytoplasm. Among the tested honeys, marjoram exhibited the highest total antibacterial activity and the highest levels of peroxide-dependent activity. The qPCR analysis showed that all honey-treated cells share a similar overall pattern of gene expression, with a trend toward reduced expression of the virulence genes of interest. Our results indicate that some varieties of the Egyptian honey have the potential to be effective inhibitor and virulence modulator of E. coli via multiple molecular targets.

Effects of Selected Egyptian Honeys on the Cellular Ultrastructure and the Gene Expression Profile of Escherichia coli

PubMed Central

Elkhatib, Walid F.

2016-01-01

The purpose of this study was to: (i) evaluate the antibacterial activities of three Egyptian honeys collected from different floral sources (namely, citrus, clover, and marjoram) against Escherichia coli; (ii) investigate the effects of these honeys on bacterial ultrastructure; and (iii) assess the anti-virulence potential of these honeys, by examining their impacts on the expression of eight selected genes (involved in biofilm formation, quorum sensing, and stress survival) in the test organism. The minimum inhibitory concentration (MIC) of the honey samples against E. coli ATCC 8739 were assessed by the broth microdilution assay in the presence and absence of catalase enzyme. Impacts of the honeys on the cellular ultrastructure and the expression profiles of the selected genes of E. coli were examined using transmission electron microscopy (TEM) and quantitative real-time polymerase chain reaction (qPCR) analysis, respectively. The susceptibility tests showed promising antibacterial activities of all the tested honeys against E. coli. This was supported by the TEM observations, which revealed “ghost” cells lacking DNA, in addition to cells with increased vacuoles, and/or with irregular shrunken cytoplasm. Among the tested honeys, marjoram exhibited the highest total antibacterial activity and the highest levels of peroxide-dependent activity. The qPCR analysis showed that all honey-treated cells share a similar overall pattern of gene expression, with a trend toward reduced expression of the virulence genes of interest. Our results indicate that some varieties of the Egyptian honey have the potential to be effective inhibitor and virulence modulator of E. coli via multiple molecular targets. PMID:26954570

Ultrastructure of Plant Leaf Cuticles in relation to Sample Preparation as Observed by Transmission Electron Microscopy

PubMed Central

Guzmán, Paula; Fernández, Victoria; García, María Luisa; Fernández, Agustín; Gil, Luis

2014-01-01

The leaf cuticular ultrastructure of some plant species has been examined by transmission electron microscopy (TEM) in only few studies. Attending to the different cuticle layers and inner structure, plant cuticles have been grouped into six general morphological types. With the aim of critically examining the effect of cuticle isolation and preparation for TEM analysis on cuticular ultrastructure, adaxial leaf cuticles of blue-gum eucalypt, grey poplar, and European pear were assessed, following a membrane science approach. The embedding and staining protocols affected the ultrastructure of the cuticles analysed. The solubility parameter, surface tension, and contact angles with water of pure Spurr's and LR-White resins were within a similar range. Differences were however estimated for resin : solvent mixtures, since Spurr's resin is combined with acetone and LR-White resin is mixed with ethanol. Given the composite hydrophilic and lipophilic nature of plant cuticles, the particular TEM tissue embedding and staining procedures employed may affect sample ultrastructure and the interpretation of the results in physicochemical and biological terms. It is concluded that tissue preparation procedures may be optimised to facilitate the observation of the micro- and nanostructure of cuticular layers and components with different degrees of polarity and hydrophobicity. PMID:24895682

Cytotoxic and apoptotic effects of bortezomib and gefitinib compared to alkylating agents on human glioblastoma cells.

PubMed

Pédeboscq, Stéphane; L'Azou, Béatrice; Passagne, Isabelle; De Giorgi, Francesca; Ichas, François; Pometan, Jean-Paul; Cambar, Jean

2008-01-01

Glioblastoma is a malignant astrocytic tumor with a median survival of about 12 months for which new therapeutic strategies are required. We therefore examined the cytotoxicity of anticancer drugs with different mechanisms of action on two human glioblastoma cell lines expressing various levels of EGFR (epidermal growth factor receptor). Apoptosis induced by these anticancer agents was evaluated by flow cytometry. The cytotoxicity of alkylating drugs followed a dose-effect curve and cytotoxicity index values were lower with carboplatin than with BCNU and temozolomide. Anti-EGFR gefitinib (10 microM) cytotoxicity on DBTRG.05-MG expressing high levels of EGFR was significantly higher than on U87-MG expressing low levels of EGFR. Carboplatin and temozolomide cytotoxicity was potentiated with the addition of gefitinib on DBTRG.05-MG. Among the anticancer agents tested, the proteasome inhibitor bortezomib was the most cytotoxic with very low IC50 on the two cell lines. Moreover, all anticancer drugs tested induced apoptosis in a concentration-dependent manner. Bortezomib proved to be a more potent inductor of apoptosis than gefitinib and alkylating agents. These results show the efficacy of bortezomib and of the association between conventional chemotherapy and gefitinib on glioblastoma cells and therefore suggest the interest of these molecules in the treatment of glioblastoma.

The effect of poloxamer 188 on nanoparticle morphology, size, cancer cell uptake, and cytotoxicity.

PubMed

Yan, Fei; Zhang, Chao; Zheng, Yi; Mei, Lin; Tang, Lina; Song, Cunxian; Sun, Hongfan; Huang, Laiqiang

2010-02-01

The aim of this work was to investigate the effect of triblock copolymer poloxamer 188 on nanoparticle morphology, size, cancer cell uptake, and cytotoxicity. Docetaxel-loaded nanoparticles were prepared by oil-in-water emulsion/solvent evaporation technique using biodegradable poly(lactic-co-glycolic acid) (PLGA) with or without addition of poloxamer 188, respectively. The resulting nanoparticles were found to be spherical with a rough and porous surface. The nanoparticles had an average size of around 200 nm with a narrow size distribution. The in vitro drug-release profile of both nanoparticle formulations showed a biphasic release pattern. An increased level of uptake of PLGA/poloxamer 188 nanoparticles in the docetaxel-resistant MCF-7 TAX30 human breast cancer cell line could be found in comparison with that of PLGA nanoparticles. In addition, the docetaxel-loaded PLGA/poloxamer 188 nanoparticles achieved a significantly higher level of cytotoxicity than that of docetaxel-loaded PLGA nanoparticles and Taxotere (P < .05). In conclusion, the results showed advantages of docetaxel-loaded PLGA nanoparticles incorporated with poloxamer 188 compared with the nanoparticles without incorporation of poloxamer 188 in terms of sustainable release and efficacy in breast cancer chemotherapy. The effects of poloxamer 188, a triblock copolymer were studied on nanoparticle morphology, size, cancer cell uptake and cytotoxicity. An increased level of uptake of PLGA/poloxamer 188 nanoparticles in resistant human breast cancer cell line was demonstrated, resulting in a significantly higher level of cytotoxicity. Copyright 2010 Elsevier Inc. All rights reserved.

Ultrastructure of spermatozoa in cobia, Rachycentron canadum (Linnaeus, 1766).

PubMed

Dhanasekar, Krishnamoorthy; Selvakumar, Narasimman; Munuswamy, Natesan

2018-02-01

Ultrastructure and development of spermatozoa in cobia, Rachycentron canadum are described. Sections through the testis show different developmental stages viz, Spermatocytes, spermatids and sperm. Spermatozoa of R. canadum exhibit the configuration of uniflagellated, anacrosomal Type I aquasperm, typical for externally fertilizing fish. Mature spermatozoon is seen with a prominent head and long cylindrical flagellum. Ultrastructure of sperm shows invaginated 'U' shaped nucleus and other organelles. The mitochondrial matrix is electron-dense with irregular arrangement of the cristae. The nucleus reveals a deep invagination (nuclear fossa) in which the centriolar complex is located. The centriolar complex lies inside the nuclear fossa and is composed of a proximal and a distal centriole. The two centrioles are placed perpendicular to each other. The flagellum has a typical eukaryotic organization (microtubule doublets 9 + 2 pattern) and measures around 36.21 ± 0.42 μm in length. This study for the first time provides a comprehensive detail on the ultrastructure and developmental process of sperm in cobia, R. canadum. Copyright © 2017 Elsevier B.V. All rights reserved.

Withania somnifera Root Extract Has Potent Cytotoxic Effect against Human Malignant Melanoma Cells

PubMed Central

Halder, Babli; Singh, Shruti; Thakur, Suman S.

2015-01-01

In Ayurveda, Withania somnifera is commonly known as Ashwagandha, its roots are specifically used in medicinal and clinical applications. It possesses numerous therapeutic actions which include anti-inflammatory, sedative, hypnotic and narcotic. Extracts from this plant have been reported for its anticancer properties. In this study we evaluated for the first time, the cytotoxic effect of Withania root extract on human malignant melanoma A375 cells. The crude extract of Withania was tested for cytotoxicity against A375 cells by MTT assay. Cell morphology of treated A375 cells was visualized through phase contrast as well as fluorescence microscopy. Agarose gel electrophoresis was used to check DNA fragmentation of the crude extract treated cells. Crude extract of Withania root has the potency to reduce viable cell count in dose as well as time dependent manner. Morphological change of the A375 cells was also observed in treated groups in comparison to untreated or vehicle treated control. Apoptotic body and nuclear blebbing were observed in DAPI stained treated cells under fluorescence microscope. A ladder of fragmented DNA was noticed in treated cells. Thus it might be said that the crude water extract of Withania somnifera has potent cytotoxic effect on human malignant melanoma A375 cells. PMID:26334881

Green vegetables, red meat and colon cancer: chlorophyll prevents the cytotoxic and hyperproliferative effects of haem in rat colon.

PubMed

de Vogel, Johan; Jonker-Termont, Denise S M L; van Lieshout, Esther M M; Katan, Martijn B; van der Meer, Roelof

2005-02-01

Diets high in red meat and low in green vegetables are associated with increased colon cancer risk. This association might be partly due to the haem content of red meat. In rats, dietary haem is metabolized in the gut to a cytotoxic factor that increases colonic cytotoxicity and epithelial proliferation. Green vegetables contain chlorophyll, a magnesium porphyrin structurally analogous to haem. We studied whether green vegetables inhibit the unfavourable colonic effects of haem. First, rats were fed a purified control diet or purified diets supplemented with 0.5 mmol haem/kg, spinach (chlorophyll concentration 1.2 mmol/kg) or haem plus spinach (n = 8/group) for 14 days. In a second experiment we also studied a group that received haem plus purified chlorophyll (1.2 mmol/kg). Cytotoxicity of faecal water was determined with a bioassay and colonic epithelial cell proliferation was quantified in vivo by [methyl-(3)H]thymidine incorporation into newly synthesized DNA. Exfoliation of colonocytes was measured as the amount of rat DNA in faeces. In both studies haem increased cytotoxicity of the colonic contents approximately 8-fold and proliferation of the colonocytes almost 2-fold. Spinach or an equimolar amount of chlorophyll supplement in the haem diet inhibited these haem effects completely. Haem clearly inhibited exfoliation of colonocytes, an effect counteracted by spinach and chlorophyll. Finally, size exclusion chromatography showed that chlorophyll prevented formation of the cytotoxic haem metabolite. We conclude that green vegetables may decrease colon cancer risk because chlorophyll prevents the detrimental, cytotoxic and hyperproliferative colonic effects of dietary haem.

Echinococcus multilocularis Leuckart, 1863 (Taeniidae): new data on sperm ultrastructure.

PubMed

Miquel, Jordi; Świderski, Zdzisław; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

2016-06-01

The present study establishes the ultrastructural organisation of the mature spermatozoon of Echinococcus multilocularis, which is essential for future research on the location of specific proteins involved in the sperm development in this species and also in Echinococcus granulosus. Thus, the ultrastructural characteristics of the sperm cell are described by means of transmission electron microscopy. The spermatozoon of E. multilocularis is a filiform cell, which is tapered at both extremities and lacks mitochondria. It exhibits all the characteristics of type VII spermatozoon of tapeworms, namely a single axoneme, crested bodies, spiralled cortical microtubules and nucleus, a periaxonemal sheath and intracytoplasmic walls. Other characteristics observed in the male gamete are the presence of a >900-nm long apical cone in its anterior extremity and only the axoneme in its posterior extremity. The ultrastructural characters of the spermatozoon of E. multilocularis are compared with those of other cestodes studied to date, with particular emphasis on representatives of the genus Taenia. The most interesting finding concerns the presence of two helical crested bodies in E. multilocularis while in the studied species of Taenia, there is only one crested body. Future ultrastructural studies of other species of the genus Echinococcus would be of particular interest in order to confirm whether or not the presence of two crested bodies is a characteristic of this genus.

Nanoscale Correlated Disorder in Out-of-Equilibrium Myelin Ultrastructure.

PubMed

Campi, Gaetano; Di Gioacchino, Michael; Poccia, Nicola; Ricci, Alessandro; Burghammer, Manfred; Ciasca, Gabriele; Bianconi, Antonio

2018-01-23

Ultrastructural fluctuations at nanoscale are fundamental to assess properties and functionalities of advanced out-of-equilibrium materials. We have taken myelin as a model of supramolecular assembly in out-of-equilibrium living matter. Myelin sheath is a simple stable multilamellar structure of high relevance and impact in biomedicine. Although it is known that myelin has a quasi-crystalline ultrastructure, there is no information on its fluctuations at nanoscale in different states due to limitations of the available standard techniques. To overcome these limitations, we have used scanning micro X-ray diffraction, which is a unique non-invasive probe of both reciprocal and real space to visualize statistical fluctuations of myelin order of the sciatic nerve of Xenopus laevis. The results show that the ultrastructure period of the myelin is stabilized by large anticorrelated fluctuations at nanoscale, between hydrophobic and hydrophilic layers. The ratio between the total thickness of hydrophilic and hydrophobic layers defines the conformational parameter, which describes the different states of myelin. Our key result is that myelin in its out-of-equilibrium functional state fluctuates point-to-point between different conformations showing a correlated disorder described by a Levy distribution. As the system approaches the thermodynamic equilibrium in an aged state, the disorder loses its correlation degree and the structural fluctuation distribution changes to Gaussian. In a denatured state at low pH, it changes to a completely disordered stage. Our results aim to clarify the degradation mechanism in biological systems by associating these states with ultrastructural dynamic fluctuations at nanoscale.

Ginger and alpha lipoic acid ameliorate age-related ultrastructural changes in rat liver.

PubMed

Mahmoud, Y I; Hegazy, H G

2016-01-01

Because of the important role that oxidative stress is thought to play in the aging process, antioxidants could be candidates for preventing its related pathologies. We investigated the ameliorative effects of two antioxidant supplements, ginger and alpha lipoic acid (ALA), on hepatic ultrastructural alterations in old rats. Livers of young (4 months) and old (24 months) Wistar rats were studied using transmission electron microscopy. Livers of old rats showed sinusoidal collapse and congestion, endothelial thickening and defenestration, and inconsistent perisinusoidal extracellular matrix deposition. Aged hepatocytes were characterized by hypertrophy, cytoplasmic vacuolization and a significant increase in the volume densities of the nuclei, mitochondria and dense bodies. Lipofuscin accumulation and decreased microvilli in bile canaliculi and space of Disse also were observed. The adverse alterations were ameliorated significantly by both ginger and ALA supplementation; ALA was more effective than ginger. Ginger and ALA appear to be promising anti-aging agents based on their amelioration of ultrastructural alterations in livers of old rats.

Cytotoxic chalcones from some Indonesian Cryptocarya

NASA Astrophysics Data System (ADS)

Kurniadewi, F.; Syah, Y. M.; Juliawaty, L. D.; Hakim, E. H.; Koyama, K.; Kinoshita, K.

2017-07-01

Malignant tumors are one of the main causes of death in the world. Until now the search for cytotoxic (antitumor) compounds from nature, particularly from plants, is being a continuation activities. One group of plants that produce potential cytotoxic compounds is the Cryptocarya, one of the large genera of the Lauraceae family. As a part of our chemical and cytotoxic evaluation of the Cryptocarya species, we examined three species of Indonesian Cryptocarya. The sample of the wood of C. konishii hayata was collected from Cibodas Botanical Garden, West Java while the stem bark of C. phoebeopsis and C. cagayanensis were obtained from Sorong, Papua. Our investigation of flavonoid constituents on these species afforded three chalcone compounds i.e. desmethylinfectocaryone (1), infectocaryone (2) and cryptocaryone (3). The molecular structures of the isolated compounds were determined based on spectroscopic data, including UV, IR, 1D and 2D NMR. Cytotoxic effects of the compounds were evaluated using MTT [3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] assay. Compound 1, 2 and 3 displayed strong cytotoxic properties (IC50 < 2 μg/mL) against Murine Leukemia P388 and HL 60 (blood premyelocytic leukemia) cells whereas 2 and 3 exhibited strong cytotoxicity properties against HCT116 (colon cancer). Cryptocaryone (3) also showed moderate cytotoxic properties (IC50 < 10 μg/mL) towards A549 (human lung adenocarcinoma epithelial) cells.

Evaluation of the cytotoxic and genotoxic effects of benchmark multi-walled carbon nanotubes in relation to their physicochemical properties.

PubMed

Louro, Henriqueta; Pinhão, Mariana; Santos, Joana; Tavares, Ana; Vital, Nádia; Silva, Maria João

2016-11-16

To contribute with scientific evidence to the grouping strategy for the safety assessment of multi-walled carbon nanotubes (MWCNTs), this work describes the investigation of the cytotoxic and genotoxic effects of four benchmark MWCNTs in relation to their physicochemical characteristics, using two types of human respiratory cells. The cytotoxic effects were analysed using the clonogenic assay and replication index determination. A 48h-exposure of cells revealed that NM-401 was the only cytotoxic MWCNT in both cell lines, but after 8-days exposure, the clonogenic assay in A549 cells showed cytotoxic effects for all the tested MWCNTs. Correlation analysis suggested an association between the MWCNTs size in cell culture medium and cytotoxicity. No induction of DNA damage was observed after any MWCNTs in any cell line by the comet assay, while the micronucleus assay revealed that both NM-401 and NM-402 were genotoxic in A549 cells. NM-401 and NM-402 are the two longest MWCNTs analyzed in this work, suggesting that length may be determinant for genotoxicity. No induction of micronuclei was observed in BBEAS-2Beas-2B cell line and the different effect in both cell lines is explained in view of the size-distribution of MWCNTs in the cell culture medium, rather than cell's specificities. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Assessment of in vitro genotoxic and cytotoxic effects of flurbiprofen on human cultured lymphocytes.

PubMed

Timocin, Taygun; Ila, Hasan Basri; Dordu, Tuba; Husunet, Mehmet Tahir; Tazehkand, Mostafa Norizadeh; Valipour, Ebrahim; Topaktas, Mehmet

2016-01-01

Flurbiprofen is non-steroidal anti-inflammatory drug which is commonly used for its analgesic, antipyretic, and anti-inflammatory effects. The purpose of the study was to explore the genotoxic and cytotoxic effects of flurbiprofen in human cultured lymphocytes by sister chromatid exchange, chromosome aberration, and cytokinesis-blocked micronucleus tests. 10, 20, 30, and 40 μg/mL concentrations of flurbiprofen (solvent is DMSO) were used to treatment of human cultured lymphocytes at two different treatment periods (24 and 48 h). Flurbiprofen had no significant genotoxic effect in any of these tests. But exposing to flurbiprofen for 24 and 48 h led to significant decrease on proliferation index, mitotic index, and nuclear division index (NDI). Also, all decreases were concentration-dependent (except NDI at 24 h treatment period). Consequently, the findings of this research showed that flurbiprofen had cytotoxic effects in human blood lymphocytes.

Ultrastructural changes of sheep cumulus-oocyte complexes following different methods of vitrification.

PubMed

Ebrahimi, Bita; Valojerdi, Mojtaba Rezazadeh; Eftekhari-Yazdi, Poopak; Baharvand, Hossein

2012-05-01

To determine the ultrastructural changes of sheep cumulus-oocyte complexes (COCs) following different methods of vitrification, good quality isolated COCs (GV stage) were randomly divided into the non-vitrified control, conventional straw, cryotop and solid surface vitrification groups. In both conventional and cryotop methods, vitrified COCs were respectively loaded by conventional straws and cryotops, and then plunged directly into liquid nitrogen (LN2); whereas in the solid surface group, vitrified COCs were first loaded by cryotops and then cooled before plunging into LN2. Post-warming survivability and ultrastructural changes of healthy COCs in the cryotop group especially in comparison with the conventional group revealed better viability rate and good preservation of the ooplasm organization. However in all vitrification groups except the cryotop group, mitochondria were clumped. Solely in the conventional straw group, the mitochondria showed different densities and were extremely distended. Moreover in the latter group, plenty of large irregular connected vesicles in the ooplasm were observed and in some parts their membrane ruptured. Also, in the conventional and solid surface vitrification groups, cumulus cells projections became retracted from the zona pellucida in some parts. In conclusion, the cryotop vitrification method as compared with other methods seems to have a good post-warming survivability and shows less deleterious effects on the ultrastructure of healthy vitrified-warmed sheep COCs.

Subconjunctival mitomycin C before pterygium excision: an ultrastructural study.

PubMed

Chang, Yi-Sheng; Chen, Wen-Chung; Tseng, Sung-Huei; Sze, Chun-I; Wu, Chao-Liang

2008-05-01

Subconjunctival injection of mitomycin C (MMC) before pterygium excision is a new adjunctive therapy to decrease pterygium recurrence. This study aimed to investigate the ultrastructural changes in pterygium after subconjunctival injection of MMC. Four patients underwent subconjunctival injection of 0.1 mL of 0.15 mg/mL MMC 1 month before pterygium excision, and 2 patients served as controls without preoperative MMC injection. The excised specimens of pterygium were examined under transmission electron microscopy. Epithelial cells of the treated pterygium remained unchanged. However, stromal fibroblasts were decreased in number, were oval rather than spindle-shaped, and had shrunken cytoplasmic processes; some were degenerating or apoptotic. Collagen and elastic fibers were decreased in density, disorganized, and degenerated. Capillary endothelial cells were thickened and swollen, with narrow or obliterated lumens. Axonal swelling and demyelination were observed. Subconjunctival injection of MMC inhibits fibrovascular activity in the pterygial stroma, leading to degeneration of the extracellular matrix and nerve axons. These ultrastructural changes are consistent with the clinical observation of reduced vascularity in the pterygium after MMC injection and verify the effectiveness of subconjunctival MMC injection 1 month before pterygium excision in decreasing the risk of pterygium recurrence.

Interleukin-2 activation of cytotoxic cells in postmastectomy seroma.

PubMed

Gercel-Taylor, C; Hoffman, J P; Taylor, D D; Owens, K J; Eisenberg, B L

1996-02-15

Lymphocytes were isolated from breast seroma fluids and used to study the mechanism of activation of cytotoxic lymphocytes and possible role of immunological potentiation following surgery in breast cancer patients. Single or serial samples were obtained from patients who had undergone mastectomy or lumpectomy with axillary node dissection. Lymphocytes were activated with rIL-2 (interleukin-2) and their cytotoxic activity was studied against Daudi and K562 cells and against a breast tumor line (SKBr-3). All of the patients (21/21) responded to IL-2 stimulation by significant activation of cytotoxic activity. The unstimulated cytotoxic activity of these cells against NK targets was low with less than 10% specific release in cytotoxicity assays. In simultaneous experiments, autologous seroma fluid was included during activation of lymphocytes to study possible regulatory molecules that may be present. In 17/21 patients, the presence of their seroma fluid, during the activation period, enhanced or did not effect the cytotoxic potential of their lymphocytes; inhibition was observed when seroma fluids from 4/21 patients were included. Analysis of the cytotoxic population derived from combined IL-2 and seroma treatments indicates the presence of cells with increased expression of CD56, and CD2, as well as in some cases CD16 expression. Cytotoxic lymphocytes derived from IL-2 and seroma treatments appeared to be more effective killers. Modulation of CD2 expression with seroma alone appeared to result in the generation of this highly cytotoxic population. This study demonstrates the role of CD2 expression in the effectiveness of LAK cell killing and also potential benefit of an immunotherapeutic approach to the postoperative treatment of carcinoma of the breast.

Isothiocyanate from Moringa oleifera seeds mitigates hydrogen peroxide-induced cytotoxicity and preserved morphological features of human neuronal cells

PubMed Central

Shaari, Khozirah; Rosli, Rozita

2018-01-01

Reactive oxygen species are well known for induction of oxidative stress conditions through oxidation of vital biomarkers leading to cellular death via apoptosis and other process, thereby causing devastative effects on the host organs. This effect is believed to be linked with pathological alterations seen in several neurodegenerative disease conditions. Many phytochemical compounds proved to have robust antioxidant activities that deterred cells against cytotoxic stress environment, thus protect apoptotic cell death. In view of that we studied the potential of glucomoringin-isothiocyanate (GMG-ITC) or moringin to mitigate the process that lead to neurodegeneration in various ways. Neuroprotective effect of GMG-ITC was performed on retinoic acid (RA) induced differentiated neuroblastoma cells (SHSY5Y) via cell viability assay, flow cytometry analysis and fluorescence microscopy by means of acridine orange and propidium iodide double staining, to evaluate the anti-apoptotic activity and morphology conservation ability of the compound. Additionally, neurite surface integrity and ultrastructural analysis were carried out by means of scanning and transmission electron microscopy to assess the orientation of surface and internal features of the treated neuronal cells. GMG-ITC pre-treated neuron cells showed significant resistance to H2O2-induced apoptotic cell death, revealing high level of protection by the compound. Increase of intracellular oxidative stress induced by H2O2 was mitigated by GMG-ITC. Thus, pre-treatment with the compound conferred significant protection to cytoskeleton and cytoplasmic inclusion coupled with conservation of surface morphological features and general integrity of neuronal cells. Therefore, the collective findings in the presence study indicated the potentials of GMG-ITC to protect the integrity of neuron cells against induced oxidative-stress related cytotoxic processes, the hallmark of neurodegenerative diseases. PMID:29723199

Isothiocyanate from Moringa oleifera seeds mitigates hydrogen peroxide-induced cytotoxicity and preserved morphological features of human neuronal cells.

PubMed

Jaafaru, Mohammed Sani; Nordin, Norshariza; Shaari, Khozirah; Rosli, Rozita; Abdull Razis, Ahmad Faizal

2018-01-01

Reactive oxygen species are well known for induction of oxidative stress conditions through oxidation of vital biomarkers leading to cellular death via apoptosis and other process, thereby causing devastative effects on the host organs. This effect is believed to be linked with pathological alterations seen in several neurodegenerative disease conditions. Many phytochemical compounds proved to have robust antioxidant activities that deterred cells against cytotoxic stress environment, thus protect apoptotic cell death. In view of that we studied the potential of glucomoringin-isothiocyanate (GMG-ITC) or moringin to mitigate the process that lead to neurodegeneration in various ways. Neuroprotective effect of GMG-ITC was performed on retinoic acid (RA) induced differentiated neuroblastoma cells (SHSY5Y) via cell viability assay, flow cytometry analysis and fluorescence microscopy by means of acridine orange and propidium iodide double staining, to evaluate the anti-apoptotic activity and morphology conservation ability of the compound. Additionally, neurite surface integrity and ultrastructural analysis were carried out by means of scanning and transmission electron microscopy to assess the orientation of surface and internal features of the treated neuronal cells. GMG-ITC pre-treated neuron cells showed significant resistance to H2O2-induced apoptotic cell death, revealing high level of protection by the compound. Increase of intracellular oxidative stress induced by H2O2 was mitigated by GMG-ITC. Thus, pre-treatment with the compound conferred significant protection to cytoskeleton and cytoplasmic inclusion coupled with conservation of surface morphological features and general integrity of neuronal cells. Therefore, the collective findings in the presence study indicated the potentials of GMG-ITC to protect the integrity of neuron cells against induced oxidative-stress related cytotoxic processes, the hallmark of neurodegenerative diseases.

Revealing 3D Ultrastructure and Morphology of Stem Cell Spheroids by Electron Microscopy.

PubMed

Jaros, Josef; Petrov, Michal; Tesarova, Marketa; Hampl, Ales

2017-01-01

Cell culture methods have been developed in efforts to produce biologically relevant systems for developmental and disease modeling, and appropriate analytical tools are essential. Knowledge of ultrastructural characteristics represents the basis to reveal in situ the cellular morphology, cell-cell interactions, organelle distribution, niches in which cells reside, and many more. The traditional method for 3D visualization of ultrastructural components, serial sectioning using transmission electron microscopy (TEM), is very labor-intensive due to contentious TEM slice preparation and subsequent image processing of the whole collection. In this chapter, we present serial block-face scanning electron microscopy, together with complex methodology for spheroid formation, contrasting of cellular compartments, image processing, and 3D visualization. The described technique is effective for detailed morphological analysis of stem cell spheroids, organoids, as well as organotypic cell cultures.

Herbicide effects on cuticle ultrastructure in Eleusine indica and Portulaca oleracea.

PubMed

Malpassi, Rosana N

2006-04-01

Eleusine indica and Portulaca oleracea are two common weeds in peanut crops in southern Córdoba. Two chemicals are frequently used to control them, quizalofop for grasses and lactofen for dicots. The objective is to study the effects of quizalofop and lactofen on cuticle ultrastructure in E. indica and P. oleracea, respectively. In the lab, quizalofop was applied on E. indica and lactofen on P. oleracea. Three plant categories were analyzed in each species: 3, 1-2, and no tiller in E. indica, and 8, 6, and 2 nomophylls in P. oleracea. Leaf samples from both species were collected at 7 and 16 days post-application and were treated for scanning electron microscopy. E. indica cuticle treated with lethal dose shows areas where epicuticular waxes disappear, specially in the youngest individuals. These areas are located predominantly on periclinal walls of typical epidermic cells and subsidiary cells. On the other hand, P. oleracea shows cuticle discontinuities that may be caused by lactofen entry. They are smaller and less frequent in plants having 8 or more nomophylls. The remaining waxes act as a herbicide accumulation compartment and, therefore, would partially prevent the active ingredient entry to epidermic cells.

Intracranial suprasellar angiolipoma: ultrastructural and immunohistochemical features.

PubMed

Lach, B; Lesiuk, H

1994-01-01

The authors present ultrastructural and immunohistochemical characteristics of an intracranial suprasellar tumor displaying features of cavernous angioma with islets of adipose tissue. Electron microscopy revealed thin-walled vessels separated by a loose collagenous stroma containing nests of mature adipocytes as well as fibroblasts, myofibroblasts, mast cells, and a few macrophages. Intracytoplasmic lipid droplets were also identified in scattered pericytes and smooth muscle cells of vascular walls and in the transitional cells resembling smooth muscle cells and adipocytes. Many adipose tissue cells were positive for S-100 protein with polyclonal antibodies. Other lipidized tumor cells were immunoreactive for some or all of the following: smooth muscle-specific actin, factor XIIIa, vimentin, and, occasionally, for desmin. Ultrastructure and immunohistochemistry indicate that in addition to typical adipocytes, lipidized cells of another nature contribute to the characteristic appearance of the adipose tissue component of angiolipoma.

Effects of buprofezin on the ultrastructure of the third instar cuticle of the insect Trialeurodes vaporariorum.

PubMed

De Cock, A; Degheele, D

1991-01-01

Treatment with buprofezin at the beginning of the third instar of Trialeurodes vaporariorum results in death of the larvae at the time of moulting. Electron microscopic observations, after treatment of the larvae with 20 mg a.i./l buprofezin, does not reveal any difference in the ultrastructural profile before apolysis, however formation of a normal lamellate procuticle is disturbed. The pharate procuticle is amorphous, varying in thickness and the mean thickness is greatly reduced. The subcuticle is interrupted several times at locations corresponding with the thinnest places of the pharate cuticle. Epidermal cells contain unusual structures such as myelin figures and hypertrophied mitochondria indicating that buprofezin may have an additional toxic effect on epidermal cells.

Structural and ultrastructural studies of the urinary tract of mice inoculated with Lactobacillus fermentum.

PubMed

Silva de Ruiz, C; del R Rey, M; Nader-Macías, M E

2003-06-01

To assess, using structural and ultrastructural studies of the urinary tract, the effects of the intraurethral inoculation of lactobacilli (probiotic treatment) as lactobacilli are the predominant micro-organisms of the urogenital tract of humans, monkeys and mice. Previous work showed the protective effect of Lactobacillus fermentum CRL 1058 intraurethrally inoculated against the challenge of uropathogenic Escherichia coli. There was also an effect of oestrogens and antibiotics in the kinetics of colonization of both micro-organisms in mice. In the present study L. fermentum was inoculated with agarose beads (107 colony-forming units) and the number of micro-organisms determined by plating in selective media, giving a high degree of colonization in all the organs studied. The urinary tract organs were processed by histological and electron microscopy techniques standardized in our laboratory. The intraurethral inoculation of lactobacilli produced no adverse effects or significant changes in any of the organs assessed (kidney, ureter, bladder or urethra), when evaluated by histological and ultrastructural techniques. The use of lactobacilli as a probiotic treatment is probably safe.

The effect of vitamin C deficiency and chronic ultraviolet-B exposure on corneal ultrastructure: a preliminary investigation

PubMed Central

Hayes, Sally; Cafaro, Thamara A.; Boguslawska, Patrycja J.; Kamma-Lorger, Christina S.; Boote, Craig; Harris, Jonathan; Young, Robert; Hiller, Jennifer; Terrill, Nicholas; Meek, Keith M.

2011-01-01

Purpose In the visually debilitating condition of climatic droplet keratopathy, corneal transparency is progressively lost. Although the precise cause of the disease and the mechanism by which it progresses are not known, a lifetime exposure to high solar radiation and a vitamin C–deficient diet may be involved in its development. This study examines the effect of dietary ascorbate levels and ultraviolet (UV)-B exposure on corneal stromal structure. Methods Eight guinea pigs were divided into four treatment groups (A, B, C, and D). For 15 weeks, Groups A and C were fed an ascorbate-rich diet (2 mg/100 g bodyweight/day), while Groups B and D received an ascorbate-deficient diet (0.07 mg/100 g bodyweight/day). For the last 12 weeks of the study, Groups C and D also experienced chronic UVB exposure (0.12 J/cm2 for 40 min/day). Following euthanasia, the corneas were enucleated and their stromal ultrastructure examined using X-ray scattering and electron microscopy. Results UVB exposure resulted in an increased corneal thickness (p<0.001), but this was not accompanied by a widespread expansion of the collagen fibrillar array, and in the case of ascorbate-deficient animals, stromal thickening was associated with the compaction of collagen fibrils (p<0.01). Neither UVB exposure nor ascorbic acid deficiency caused any change in the average diameter or D-periodicity of the stromal collagen fibrils. Conclusions UVB-induced changes in the corneal ultrastructure were most pronounced in animals fed an ascorbic acid–deficient diet. This suggests that ascorbic acid may play a vital role in protecting the corneal stroma from the harmful effects of UVB. PMID:22171156

Cytotoxicity of Protein-Carbon Nanotubes on J774 Macrophages Is a Functionalization Grade-Dependent Effect

PubMed Central

Montes-Fonseca, Silvia Lorena; Sánchez-Ramírez, Blanca; Luna-Velasco, Antonia; Arzate-Quintana, Carlos; Silva-Cazares, Macrina Beatriz; González Horta, Carmen

2015-01-01

Carbon nanotubes (CNTs) are used as carriers in medicine due to their ability to be functionalized with chemical substances. However, cytotoxicity analysis is required prior to use for in vivo models. The aim of this study was to evaluate the cytotoxic effect of CNTs functionalized with a 46 kDa surface protein from Entamoeba histolytica (P46-CNTs) on J774A macrophages. With this purpose, CNTs were synthesized by spray pyrolysis and purified (P-CNTs) using sonication for 48 h. A 46 kDa protein, with a 4.6–5.4 pI range, was isolated from E. histolytica HM1:IMSS strain trophozoites using an OFFGEL system. The P-CNTs were functionalized with the purified 46 kDa protein, classified according to their degree of functionalization, and characterized by Raman and Infrared spectroscopy. In vitro cytotoxicity was evaluated by MTT, apoptosis, and morphological assays. The results demonstrated that P46-CNTs exhibited cytotoxicity dependent upon the functionalized grade. Contrary to what was expected, P46-CNTs with a high grade of functionalization were more toxic to J774 macrophages than P46-CNTs with a low grade of functionalization, than P-CNTs, and had a similar level of toxicity as UP-CNT. This suggests that the nature of the functionalized protein plays a key role in the cytotoxicity of these nanoparticles. PMID:26075262

Magnesium Alleviates Adverse Effects of Lead on Growth, Photosynthesis, and Ultrastructural Alterations of Torreya grandis Seedlings.

PubMed

Shen, Jie; Song, Lili; Müller, Karin; Hu, Yuanyuan; Song, Yang; Yu, Weiwu; Wang, Hailong; Wu, Jiasheng

2016-01-01

Magnesium (Mg 2+ ) has been shown to reduce the physiological and biochemical stress in plants caused by heavy metals. To date our understanding of how Mg 2+ ameliorates the adverse effects of heavy metals in plants is scarce. The potential effect of Mg 2+ on lead (Pb 2+ ) toxicity in plants has not yet been studied. This study was designed to clarify the mechanism of Mg 2+ -induced alleviation of lead (Pb 2+ ) toxicity. Torreya grandis ( T. grandis ) seedlings were grown in substrate contaminated with 0, 700 and 1400 mg Pb 2+ per kg -1 and with or without the addition of 1040 mg kg -1 Mg 2+ . Growth parameters, concentrations of Pb 2+ and Mg 2+ in the plants' shoots and roots, photosynthetic pigment, gas exchange parameters, the maximum quantum efficiency (Fv/Fm), root oxidative activity, ultrastructure of chloroplasts and root growth were determined to analyze the effect of different Pb 2+ concentrations on the seedlings as well as the potential ameliorating effect of Mg 2+ on the Pb 2+ induced toxicity. All measurements were tested by a one-way ANOVA for the effects of treatments. The growth of T. grandis seedlings cultivated in soils treated with 1400 mg kg -1 Pb 2+ was significantly reduced compared with that of plants cultivated in soils treated with 0 or 700 mg kg -1 Pb 2+ . The addition of 1040 mg kg -1 Mg 2+ improved the growth of the Pb 2+ -stressed seedlings, which was accompanied by increased chlorophyll content, the net photosynthetic rate and Fv/Fm, and enhanced chloroplasts development. In addition, the application of Mg 2+ induced plants to accumulate five times higher concentrations of Pb 2+ in the roots and to absorb and translocate four times higher concentrations of Mg 2+ to the shoots than those without Mg 2+ application. Furthermore, Mg 2+ addition increased root growth and oxidative activity, and protected the root ultrastructure. To the best of our knowledge, our study is the first report on the mechanism of Mg 2+ -induced alleviation of Pb

Pharmacologic modification of the cytotoxic effects of cadmium in LLC-PK sub 1 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battaglia, D.R.; Kahan, B.S.; Niewenhuis, R.J.

1989-02-09

Recent results from our laboratories have shown that exposure to cadmium causes LLC-PK{sub 1} cells to shrink, detach and assume a spherical shape. The purpose of the present studies was to determine whether various pharmacologic agents can reduce or prevent these cytotoxic effects of Cd{sup 2+}. Confluent monolayers of LLC-PK{sub 1} cells were incubated with the drugs of interest (50 microM final concentration) for 2 hours. CadCl{sub 2} (final concentration = 75 microM) was then added and the cells were incubated for another 20 hours. Morphologic changes were assessed qualitatively by viewing the cells with a phase contrast microscope. Themore » extent of Cd{sup 2+}-induced cellular damage was also quantified by staining the cells that remained on the growing surface with methylene blue, solubilizing the stained cells, and determining the absorbance at 660 nm. The results showed that several drugs, particularly the calmodulin antagonists trifluoperazine chlorpromazine, and the calcium channel blocker verapamil, significant reduced the severity of Cd{sup 2+}-induced cytotoxicity. By contrast, a variety of other agents, such as chlorpromazine sulfoxide, trifluoperazine sulfoxide, phenytoin and zinc, had no such protective effect. These findings indicate that Ca{sup 2+} antagonists can attenuate the cytotoxic effects of Cd{sup 2+} and that Cd{sup 2+} may produce some of its effects by activating Ca{sup 2+} -dependent systems.« less

Differential role of thiopurine methyltransferase in the cytotoxic effects of 6-mercaptopurine and 6-thioguanine on human leukemia cells.

PubMed

Karim, Hazhar; Ghalali, Aram; Lafolie, Pierre; Vitols, Sigurd; Fotoohi, Alan K

2013-07-26

The thiopurine antimetabolites, 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG) are inactive pro-drugs that require intracellular metabolism for activation to cytotoxic metabolites. Thiopurine methyltransferase (TPMT) is one of the most important enzymes in this process metabolizing both 6-MP and 6-TG to different methylated metabolites including methylthioinosine monophosphate (meTIMP) and methylthioguanosine monophosphate (meTGMP), respectively, with different suggested pharmacological and cytotoxic properties. While meTIMP is a potent inhibitor of de novo purine synthesis (DNPS) and significantly contributes to the cytotoxic effects of 6-MP, meTGMP, does not add much to the effects of 6-TG, and the cytotoxicity of 6-TG seems to be more dependent on incorporation of thioguanine nucleotides (TGNs) into DNA rather than inhibition of DNPS. In order to investigate the role of TPMT in metabolism and thus, cytotoxic effects of 6-MP and 6-TG, we knocked down the expression of the gene encoding the TPMT enzyme using specifically designed small interference RNA (siRNA) in human MOLT4 leukemia cells. The knock-down was confirmed at RNA, protein, and enzyme function levels. Apoptosis was determined using annexin V and propidium iodide staining and FACS analysis. The results showed a 34% increase in sensitivity of MOLT4 cells to 1μM 6-TG after treatment with TPMT-targeting siRNA, as compared to cells transfected with non-targeting siRNA, while the sensitivity of the cells toward 6-MP was not affected significantly by down-regulation of the TPMT gene. This differential contribution of the enzyme TPMT to the cytotoxicity of the two thiopurines is probably due to its role in formation of the meTIMP, the cytotoxic methylated metabolite of 6-MP, while in case of 6-TG methylation by TPMT substantially deactivates the drug. Copyright © 2013 Elsevier Inc. All rights reserved.

[THE EFFECT OF ACID RAIN ON ULTRASTRUCTURE AND FUNCTIONAL PARAMETERS OF PHOTOSYNTHETIC APPARATUS OF PEA LEAVES].

PubMed

Polishchuk, A V; Vodka, M V; Belyavskaya, N A; Khomochkin, A P; Zolotareva, E K

2016-01-01

The effects of simulated acid rain (SAR) on the ultrastructure and functional parameters of the photosynthetic apparatus were studied using 14-day-old pea leaves as test system. Pea plants were sprayed with an aqueous solution containing NaNO₃(0.2 mM) and Na₂SO₄(0.2 mM) (pH 5.6, a control variant), or with the same solution, which was acidified to pH 2.5 (acid variant). Functional characteristics were determined by chlorophyll fluorescence analysis. Acid rain application caused reduction in the efficiency of the photosynthetic electron transport by 25%, which was accompanied by an increase by 85% in the quantum yield of thermal dissipation of excess light quanta. Ultrastructural changes in chloroplast were registered by transmission electron microscopy (TEM) after two days of the SAR-treatment of pea leaves. In this case, the changes in the structure of grana, heterogeneity of thylakoids packaging in granum, namely, the increase of intra-thylakoid gaps and thickness of granal thylakoids compared to the control were found. The migration of protein complexes in thylakoid membranes of chloroplasts isolated from leaves treated with SAR was suppressed. It was shown also that carbonic anhydrase activity was inhibited in chloroplast preparations isolated from SAR-treated pea leaves. We proposed a hypothesis on the possible inactivation of thylakoid carbonic anhydrase under SAR and its involvement in the inhibition of photochemical activity of chloroplasts. The data obtained allows to suggest that acid rains negatively affect the photosynthetic apparatus disrupting the membrane system of chloroplast.

The Genotoxic and Cytotoxic Effects of Bisphenol-A (BPA) in MCF-7 Cell Line and Amniocytes.

PubMed

Aghajanpour-Mir, Seyed Mohsen; Zabihi, Ebrahim; Akhavan-Niaki, Haleh; Keyhani, Elahe; Bagherizadeh, Iman; Biglari, Sajjad; Behjati, Farkhondeh

2016-01-01

Bisphenol-A (BPA) is an industrial xenoestrogen used widely in our living environment. Recently, several studies suggested that BPA has destructive effects on DNA and chromosomes in normal body cells via estrogen receptors (ER). Therefore, BPA could be considered as an important mediator in many diseases such as cancer. However, there are still many controversial issues which need clarification. In this study, we investigated the BPA-induced chromosomal damages in MCF-7 cell line, ER-positive and negative amniocyte cells. Cytotoxicity and genotoxicity effects of BPA were also compared between these three cell groups. Expression of estrogen receptors was determined using immunocytochemistry technique. The cell cytotoxicity of BPA was measured by MTT assay. Classic cytogenetic technique was carried out for the investigation of chromosome damage. BPA, in addition to cytotoxicity, had remarkable genotoxicity at concentrations close to the traceable levels in tissues or biological fluids. Although some differences were observed in the amount of damages between ER-positive and negative fetal cells, interestingly, these differences were not significant. The present study showed that BPA could lead to chromosomal aberrations in both ER-dependent and independent pathways at some concentrations or in cell types yet not reported. Also, BPA could probably be considered as a facilitator for some predisposed cells to be cancerous by raising the chromosome instability levels. Finally, estrogen receptor seems to have a different role in cytotoxicity and genotoxicity effects.

CYTOTOXIC EFFECTS OF SOME MINERAL DUSTS ON SYRIAN HAMSTER PERITONEAL MACROPHAGES

PubMed Central

Bey, Elke; Harington, J. S.

1971-01-01

Hamster peritoneal macrophages were grown in cell culture and their response to various conditions was examined. The cultures responded favorably to high concentrations of serum and to medium which had been preconditioned by contact with tumor cells. After 2–3 days of adaptation, they entered into a period of stability which lasted from the 4th to the 9th day. Macrophage cultures in this stable phase were treated with various samples of mineral dusts and their response determined by counting the number of viable macrophages/cm2 at intervals over a period of 72 hr. Crystalline silica Snowit was found to be nontoxic. Amorphous silica Fransil caused a characteristic cytotoxic effect and a rapid decline in cell population at doses less than 150 µg/5 x 105 cells. Of the three different kinds of asbestos used, chrysotile was toxic and amosite and crocidolite nontoxic at equivalent concentrations. A comparison of two preparations of chrysotile which differed in surface area showed that weight rather than surface area determines toxicity. Pretreatment of chrysotile with tryptose phosphate broth under drastic conditions accelerated but did not increase the final intensity of the cytotoxic effect. PMID:4101804

Microbial-assisted synthesis and evaluation the cytotoxic effect of tellurium nanorods.

PubMed

Forootanfar, Hamid; Amirpour-Rostami, Sahar; Jafari, Mandana; Forootanfar, Amir; Yousefizadeh, Zahra; Shakibaie, Mojtaba

2015-04-01

The present study was designed to isolate bacterial strain capable of tellurium nanorods' (Te NRs) production followed by purification and evaluation of the cytotoxic effect of Te NRs. Among 25 environmental samples collected for screening of Te NR-producer bacterial strains one bacterial colony (isolated from hot spring and identified as Pseudomonas pseudoalcaligenes strain Te) was selected and applied for biosynthesis of Te NRs. Thereafter, an organic-aqueous partitioning system was applied for the purification of the biogenic Te NRs and the purified Te NRs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction spectroscopy (XRD), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR) techniques. The cytotoxic effect of biologically synthesized Te NRs and potassium tellurite on four cell lines of MCF-7, HT1080, HepG2 and A549 was then determined using the MTT assay method. The obtained results revealed lower toxicity for the rod-shaped biogenic tellurium nanostructures (~22nm diameter by 185nm length) compared to K2TeO3. Copyright © 2014. Published by Elsevier B.V.

Crosslinking effect of dialdehyde starch (DAS) on decellularized porcine aortas for tissue engineering.

PubMed

Wang, Xu; Gu, Zhipeng; Qin, Huanhuan; Li, Li; Yang, Xu; Yu, Xixun

2015-08-01

Biological tissue-derived biomaterials must be chemically modified to avoid immediate degradation and immune response before being implanted in human body to replace malfunctioning organs. DAS with active aldehyde groups was employed to replace glutaraldehyde (GA), a most common synthetic crosslinking reagent in clinical practice, to fix bioprostheses for lower cytotoxicity. The aim of this research was to evaluate fixation effect of DAS. The tensile strength, crosslinking stability, cytotoxicity especially the anti-calcification capability of DAS-fixed tissues were investigated. The tensile strength and resistance to enzymatic degradation of samples were increased after DAS fixation, the values maintained stably in D-Hanks solution for several days. Meanwhile, ultrastructure of samples preserved well and the anti-calcification capability of samples were improved, the amount of positive staining points in the whole visual field of 15% DAS-fixed samples was only 0.576 times to GA-fixed ones. Moreover, both unreacted DAS and its hydrolytic products were nontoxic in cytotoxicity study. The results demonstrated DAS might be an effective crosslinking reagent to fix biological tissue-derived biomaterials in tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

Microstructure and Ultrastructure Alterations in the Pallium of Immature Mice Exposed to Cadmium.

PubMed

Yang, X F; Han, Q G; Liu, D Y; Zhang, H T; Fan, G Y; Ma, J Y; Wang, Z L

2016-11-01

The aim of this study was to investigate microstructure and ultrastructure alterations in the pallium of immature mice exposed to cadmium. Forty immature mice were randomly divided into control, 1/100 LD 50 (1.87 mg/kg, low), 1/50 LD 50 (3.74 mg/kg, medium), and 1/25 LD 50 (7.48 mg/kg, high) dose groups. After oral cadmium exposure for 40 days, the pallium of mice was obtained for microstructure and ultrastructure studies. The results showed that both microstructure and ultrastructure alterations of the pallium were observed in all treated mice and the most obvious alterations were in the high dose group. Microstructural analysis showed seriously congested capillary in the pia mater of the pallium in the high cadmium group. Meanwhile, vacuolar degenerate or karyopyknosis presented in some neurocytes, capillary quantity, and the number of apoptotic cells increased, some neurocytes became hypertrophy, the pia mater separated from the cortex, and local hemorrhage and accompanied inflammatory cell infiltration were also observed. Ultrastructural analysis showed that rough endoplasmic reticulum was expanded, heterochromatin marginalized, perinuclear space distinctly broadened, swelling and vacuolization mitochondria appeared, synapse was swelling, presynaptic and postsynaptic membranes presented fusion, and most of mitochondrial cristae were ambiguous. The results indicated that cadmium exposure for 40 days induced dose-dependent microstructure and ultrastructure alterations in pallium of immature mice.

Effects of the ACTH(4-9) analogue, ORG 2766, on vincristine cytotoxicity in two human lymphoma cell lines, U937 and U715.

PubMed Central

Kiburg, B.; van de Loosdrecht, A. A.; Schweitzer, K. M.; Ossenkoppele, G. J.; Müller, L. J.; Heimans, J. J.; Huijgens, P. C.

1994-01-01

The use of cytotoxic drug vincristine (VCR) is limited by the occurrence of peripheral neuropathy. A neurotrophic ACTH(4-9) analogue, ORG 2766, is being studied for its protective effect. Possible modulatory effects of ORG 2766 on tumour cell growth and interference with the cytotoxic efficacy of VCR were studied in two human lymphoma cell lines, U937 and U715. The effects of ORG 2766 on cell growth and survival and on VCR-mediated cytotoxicity were investigated using two MTT-based assays to study direct cytotoxic effects and to assess residual growth after pretreatment. Treatment with ORG 2766 alone had no effect on cell growth and survival. Neither did this drug affect VCR cytotoxicity. However, after 96 h pretreatment with ORG 2766 and a culture period of 7 days, a reduction in residual growth and a potentiation of VCR-induced inhibition of growth capacity was observed in U715 cells, and to some extent also in U937 cells. It is concluded that ORG 2766 has no stimulatory effects on tumour growth and does not negatively interfere with VCR-mediated cytotoxicity. Rather it enhances the cytostatic effect of VCR. It is suggested that ORG 2766 can safely be used in clinical trials investigating the ability of ORG 2766 to counteract VCR-induced neurotoxicity. PMID:8123480

A Tetrameric Peptide Derived from Bovine Lactoferricin Exhibits Specific Cytotoxic Effects against Oral Squamous-Cell Carcinoma Cell Lines.

PubMed

Solarte, Víctor A; Rosas, Jaiver E; Rivera, Zuly J; Arango-Rodríguez, Martha L; García, Javier E; Vernot, Jean-Paul

2015-01-01

Several short linear peptides derived from cyclic bovine lactoferricin were synthesized and tested for their cytotoxic effect against the oral cavity squamous-cell carcinoma (OSCC) cell lines CAL27 and SCC15. As a control, an immortalized and nontumorigenic cell line, Het-1A, was used. Linear peptides based on the RRWQWR core sequence showed a moderate cytotoxic effect and specificity towards tumorigenic cells. A tetrameric peptide, LfcinB(20-25)4, containing the RRWQWR motif, exhibited greater cytotoxic activity (>90%) in both OSCC cell lines compared to the linear lactoferricin peptide or the lactoferrin protein. Additionally, this tetrameric peptide showed the highest specificity towards tumorigenic cells among the tested peptides. Interestingly, this effect was very fast, with cell shrinkage, severe damage to cell membrane permeability, and lysis within one hour of treatment. Our results are consistent with a necrotic effect rather than an apoptotic one and suggest that this tetrameric peptide could be considered as a new candidate for the therapeutic treatment of OSCC.

The ultrastructural research of liver in experimental obstructive jaundice and effect of honey.

PubMed

Kilicoglu, Bulent; Gencay, Cem; Kismet, Kemal; Serin Kilicoglu, Sibel; Erguder, Imge; Erel, Serap; Sunay, Asli Elif; Erdemli, Esra; Durak, Ilker; Akkus, Mehmet Ali

2008-02-01

To examine the effects of honey on oxidative stress and apoptosis in experimental obstructive jaundice model. Thirty rats were divided into 3 groups: group I, sham-operated; group II, ligation and division of the common bile duct (BDL); group III, BDL followed by oral supplementation of honey 10 g/kg/d. Liver samples were examined under light microscope and transmission electron microscope. Hepatocyte apoptosis was quantitated using the terminal deoxy-nucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. Plasma and blood malondialdehyde (MDA) and glutation activities were measured for determining the oxidative stress. The liver levels of MDA and GSH were significantly different between the honey and BDL groups (P = .006 and .001, respectively). However, there was no significant difference between the plasma MDA and GSH levels of these groups (P > .05). In group III, significant reductions in the size of enlarged hepatocytes and the edema were demonstrated. The dilatation of the bile canaliculi dramatically turned to original dimention. By TUNEL assay, it was shown that administration of honey decreased the number of apoptotic cells. In the present study, we found that honey diminished the negative effects of BDL on the hepatic ultrastructure. We conclude that this effect might be due to its antioxidant and anti-inflammatory activities.

Building blocks of the GIPU, Italian Group of Ultrastructural Pathology.

PubMed

Papa, V; Costa, R; Cenacchi, G

2016-06-01

The Italian Group of Ultrastructural Pathology, GIPU, is a scientific organization committed to promote the art and science of Electron Microscopy (EM) in the pathology field in Italy, sharing its professional work with a public audience. The history of the GIPU goes back to 1990s when a founder group set up the Italian Group of Ultrastructural Diagnostic (GIDU) in Milan. The central focus of annual meetings was on EM, transmission and scanning one, about interesting cases in which it was instrumental in diagnosis. In the 1990s, ultrastructure was still the gold standard for cell/tissue morphology, biology, biochemistry, diagnostic pathology, and played an important role in tailored medicine. So, especially transmission EM, could play a critical role in the diagnosis of various diseases as in human as in animals. Best topics of the annual scientific meetings of the group were kidney, muscle, heart, and liver pathology, infertility, neuropathology, respiratory diseases, skin diseases, storage diseases, tumor pathology, infectious diseases, parasitology, veterinary pathology and more. Nowadays, EM is a method whose importance for diagnosis and pathology is well established: it is still essential in several pathologies, helpful in others, and welcome implemented in eclectic research pathology. Omission of EM likely makes the studies suboptimal and wasteful. So, from 2007 the name of the group has been changed to the Italian Group of Ultrastructural Pathology (GIPU) to favor broader applications of EM also to pathology research field. During last decades, GIDU/GIPU has interconnected with international (Society for Ultrastructural Pathology) and european (European Society of Pathology and Joint Meeting with the European Electron Microscopy Working Group) scientific society, according its statute. By 1991, GIPU has had 40 members: membership in this Group is still open and welcome to all pathologists, PhD, electron microscopy technologists, pathology trainees, and

Natural history of experimental intestinal atresia: morphologic and ultrastructural study.

PubMed

Baglaj, S M; Czernik, J; Kuryszko, J; Kuropka, P

2001-09-01

The aim of this study was to evaluate a natural history of congenital intestinal atresia (IA) in the chick embryo and to assess the type and nature of changes in the intestine at various developmental stages. Chick embryos underwent operative induction of IA on the 12th day of incubation. The procedure consisted of electrocoagulation of the mesenteric vessels supplying a 7- to 8-mm intestinal segment. The embryos were subjected to macroscopic examination, histologic and ultrastructural studies of the preatretic and postatretic bowel using the light microscope, scanning, and transmission electron microscopes. All investigations were performed in an experimental group (operated embryos), in a control group, and in a sham-operated group on the 15th, 17th, 19th, and 21st day of incubation. The original technique of an iatrogenic "vascular event" proved to be effective because IA developed in 96% of embryos surviving the procedure. The affected portion of the bowel underwent progressive necrosis, and signs of bowel obstruction could be observed 48 hours after operation. Cord atresia (type II) developed in 81% of embryos. Histologic investigations showed progressive thinning of mucosa, flattening of mucosal folds, and epithelial detachment within the intestine proximal to atresia. There was only mild hypertrophy of the muscular layers. All these pathomorphologic changes were of rapidly progressive nature until the 17th day of incubation. Later, the rate of distension of preatretic bowel and histologic changes were less. Ultrastructural investigation of the proximal bowel showed progressive flattening of the enterocytes associated with their apical bulging, widening of the intercellular spaces, and microvilli atrophy. Surprisingly, at days 19 and 21 of incubation, signs of induction of adaptive mechanisms with partial restoration of near-normal microvilli pattern were observed. Study of natural history of experimental IA indicates that histologic and ultrastructural

Ultrastructural changes and Heat Shock Proteins 70 induced by atmospheric pollution are similar to the effects observed under in vitro heavy metals stress in Conocephalum conicum (Marchantiales--Bryophyta).

PubMed

Basile, Adriana; Sorbo, Sergio; Conte, Barbara; Cardi, Manuela; Esposito, Sergio

2013-11-01

Changes in ultrastructure and induction of Heat Shock Proteins 70 have been studied in Conocephalum conicum (Marchantiales) collected in different urban and country sites in Italy. These results were compared to the effects in vitro of exposition to different heavy metals for several days. At urban sites, cellular ultrastructure was modified, and heavy metals could be observed accumulating in cell walls. Simultaneously, a strong increment in Hsp70 was detected, compared with results observed on control specimens. When C. conicum was exposed to heavy metals in vitro, comparable effects as in polluted sites were observed: Cd and Pb accumulated mostly within parenchyma and, within cells, were absorbed to cell walls or concentrated in vacuoles. Moreover, severe alterations were observed in organelles. Concomitantly, a progressive accumulation of Hsp70 was detected following heavy metals exposition. These effects are discussed in order to describe the dose and time-dependent response to heavy metal stress in C. conicum. Copyright © 2013 Elsevier Ltd. All rights reserved.

High pressure processing of meat: effects on ultrastructure and protein digestibility.

PubMed

Kaur, Lovedeep; Astruc, Thierry; Vénien, Annie; Loison, Olivier; Cui, Jian; Irastorza, Marion; Boland, Mike

2016-05-18

The effects of high pressure processing (HPP, at 175 and 600 MPa) on the ultrastructure and in vitro protein digestion of bovine longissimus dorsi muscle meat were studied. HPP caused a significant change in the visual appearance and texture of the meat subjected to HPP at 600 MPa so that it appeared similar to cooked meat, unlike the meat subjected to HPP at 175 MPa that showed no significant visible change in the colour and texture compared to the raw meat. The muscles were subjected to digestion under simulated gastric conditions for 1 h and then under simulated small-intestinal conditions for a further 2 h. The digests were analysed using gel electrophoresis (SDS-PAGE) and ninhydrin assay for amino N. The effect of the acid conditions of the stomach alone was also investigated. Reduced SDS-PAGE results showed that pepsin-digested (60 min) HPP meats showed fewer proteins or peptides of high molecular weight than the pepsin-digested untreated meat, suggesting more breakdown of the parent proteins in HPP-treated meats. This effect was more pronounced in the muscles treated at 600 MPa. These results are in accordance with microscopy results, which showed greater changes in the myofibrillar structure after simulated gastric digestion of the sample processed at 600 MPa than at 175 MPa. Transmission electron microscopy also showed the presence of protein aggregates in the former sample, resulting probably from protein denaturation of sarcoplasmic proteins, in the subcellular space and between myofibrils; along with cell contraction (similar to that caused by heating) in the former.

Analysis of cytotoxic effects of silver nanoclusters on human peripheral blood mononuclear cells 'in vitro'.

PubMed

Orta-García, Sandra Teresa; Plascencia-Villa, Germán; Ochoa-Martínez, Angeles Catalina; Ruiz-Vera, Tania; Pérez-Vázquez, Francisco Javier; Velázquez-Salazar, J Jesús; Yacamán, Miguel José; Navarro-Contreras, Hugo Ricardo; Pérez-Maldonado, Iván N

2015-10-01

The antimicrobial properties of silver nanoparticles (AgNPs) have made these particles one of the most used nanomaterials in consumer products. Therefore, an understanding of the interactions (unwanted toxicity) between nanoparticles and human cells is of significant interest. The aim of this study was to assess the in vitro cytotoxicity effects of silver nanoclusters (AgNC, < 2 nm diameter) on peripheral blood mononuclear cells (PBMC). Using flow cytometry and comet assay methods, we demonstrate that exposure of PBMC to AgNC induced intracellular reactive oxygen species (ROS) generation, DNA damage and apoptosis at 3, 6 and 12 h, with a dose-dependent response (0.1, 1, 3, 5 and 30 µg ml(-1)). Advanced electron microscopy imaging of complete and ultrathin-sections of PBMC confirmed the cytotoxic effects and cell damage caused by AgNC. The present study showed that AgNC produced without coating agents induced significant cytotoxic effects on PBMC owing to their high aspect ratio and active surface area, even at much lower concentrations (<1 µg ml(-1)) than those applied in previous studies, resembling what would occur under real exposure conditions to nanosilver-functionalized consumer products. Copyright © 2015 John Wiley & Sons, Ltd.

Ultrastructure of canine meninges after repeated epidural injection of S(+)-ketamine.

PubMed

Acosta, Alinne; Gomar, Carmen; Bombí, Josep A; Graça, Dominguita L; Garrido, Marta; Krauspenhar, Cristina

2006-01-01

The safety of ketamine when administered by the spinal route must be confirmed in various animal species before it is approved for use in humans. This study evaluates the ultrastructure of canine meninges after repeated doses of epidural S(+)-ketamine. Five dogs received S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days through an epidural catheter with its tip located at the L5 level. One dog received the same volume of normal saline at the same times. The spinal cord and meninges were processed for histopathological and ultrastructural studies. Clinical effects were assessed after each injection. Motor and sensory block appeared after each injection of S(+)-ketamine, but not in the dog receiving saline. No signs of clinical or neurologic alterations were observed. Using light microscopy, no meningeal layer showed alterations except focal infiltration at the catheter tip level by macrophages, lymphocytes, and a few mast cells. The cells of different layers were studied by electron microscopy and interpreted according to data from human and other animal species because no ultrastructural description of the canine meninges is currently available. There were no cellular signs of inflammation, phagocytosis, or degeneration in meningeal layers and no signs of atrophy, compression, or demyelinization in the areas of dorsal root ganglia and spinal cord around the arachnoid. These findings were common for dogs receiving S(+)-ketamine and the dog receiving saline. Repeated doses of epidural S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days was not associated to cellular alterations in canine meninges.

The effect of bicarbonate on menadione-induced redox cycling and cytotoxicity: potential involvement of the carbonate radical.

PubMed

Aljuhani, Naif; Michail, Karim; Karapetyan, Zubeida; Siraki, Arno G

2013-10-01

We have investigated the effect of NaHCO3 on menadione redox cycling and cytotoxicity. A cell-free system utilized menadione and ascorbic acid to catalyze a redox cycle, and we utilized murine hepatoma (Hepa 1c1c7) cells for in vitro experiments. Experiments were performed using low (2 mmol/L) and physiological (25 mmol/L) levels of NaHCO3 in buffer equilibrated to physiological pH. Using oximetry, ascorbic acid oxidation, and ascorbyl radical detection, we found that menadione redox cycling was enhanced by NaHCO3. Furthermore, Hepa 1c1c7 cells treated with menadione demonstrated cytotoxicity that was significantly increased with physiological concentrations of NaHCO3 in the media, compared with low levels of NaHCO3. Interestingly, the inhibition of superoxide dismutase (SOD) with 2 different metal chelators was associated with a protective effect against menadione cytotoxicity. Using isolated protein, we found a significant increase in protein carbonyls with menadione-ascorbate-SOD with physiological NaHCO3 levels; low NaHCO3 or SOD-free reactions produced lower levels of protein carbonyls. In conclusion, these findings suggest that the hydrogen peroxide generated by menadione redox cycling together with NaHCO3-CO2 are potential substrates for SOD peroxidase activity that can lead to carbonate-radical-enhanced cytotoxicity. These findings demonstrate the importance of NaHCO3 in menadione redox cycling and cytotoxicity.

Cytotoxic effect induced by retinoic acid loaded into galactosyl-sphingosine containing liposomes on human hepatoma cell lines.

PubMed

Díaz, Cecilia; Vargas, Ernesto; Gätjens-Boniche, Omar

2006-11-15

Two retinoids, ATRA and 13cisRA, were incorporated into liposomes of different composition and charge and added to two hepatoma cell lines with different degree of transformation to measure cytotoxicity by MTT assay. Retinoid-free cationic liposomes were more toxic than the other kinds (anionic and made only of PC) but were also the best delivery system for retinoic acid to induce specific cytotoxic effects on these tumor hepatoma cell lines. Galactosyl-sphingosine containing cationic liposomes increased the cytotoxic effect induced by ATRA on Hep3B cells when compared to glucosyl-sphingosine cationic liposomes, but did not improve the effect induced by free retinoid or ATRA loaded into liposomes without glycolipids. This suggests that in this cell line, ATRA is being incorporated by a mechanism mediated by the asialoglycoprotein receptor, but at the same time, non-specific sugar-independent capture is also taking place as well as free diffusion of ATRA directly through the membrane. Galactose-specific effect was not observed in HepG2 cells treated with ATRA or both cell lines treated with 13cisRA. In fact, treatment of HepG2 cells with retinoids entrapped into liposomes likely induces proliferation instead of cytotoxicity, a result that interferes with the measurement of cell death by MTT. Compared to the specific effect of ATRA entrapped into cationic liposomes, vesicles made only by PC, did not mediate a specific mechanism, since differences between ATRA in galactosyl- and glucosyl-shpingosine PC-liposomes were not statistically significant. The specific mechanism was not present in the myoblastic cell line C2C12, where ATRA incorporated into galactosyl- and glucosyl-sphingosine containing cationic and PC-liposomes, was able to induce cytotoxicity at the same extent. Micelles containing ATRA and galactosyl-sphingosine had a significantly more toxic effect than the retinoid administered together with glucosyl-sphingosine, in Hep3B cells. Also, micelles containing

Microwave Processing for Sample Preparation to Evaluate Mitochondrial Ultrastructural Damage in Hemorrhagic Shock

NASA Astrophysics Data System (ADS)

Josephsen, Gary D.; Josephsen, Kelly A.; Beilman, Greg J.; Taylor, Jodie H.; Muiler, Kristine E.

2005-12-01

This is a report of the adaptation of microwave processing in the preparation of liver biopsies for transmission electron microscopy (TEM) to examine ultrastructural damage of mitochondria in the setting of metabolic stress. Hemorrhagic shock was induced in pigs via 35% total blood volume bleed and a 90-min period of shock followed by resuscitation. Hepatic biopsies were collected before shock and after resuscitation. Following collection, biopsies were processed for TEM by a rapid method involving microwave irradiation (Giberson, 2001). Samples pre- and postshock of each of two animals were viewed and scored using the mitochondrial ultrastructure scoring system (Crouser et al., 2002), a system used to quantify the severity of ultrastructural damage during shock. Results showed evidence of increased ultrastructural damage in the postshock samples, which scored 4.00 and 3.42, versus their preshock controls, which scored 1.18 and 1.27. The results of this analysis were similar to those obtained in another model of shock (Crouser et al., 2002). However, the amount of time used to process the samples was significantly shortened with methods involving microwave irradiation.

Cytotoxic effects of resin-modified orthodontic band adhesives. Are they safe?

PubMed

Malkoc, Siddik; Corekci, Bayram; Botsali, Hayriye Esra; Yalçin, Muhammet; Sengun, Abdülkadir

2010-09-01

To evaluate the cytotoxic effects of three different resin-modified orthodontic band adhesives. Three resin-modified orthodontic band adhesives (Bisco Ortho Band Paste LC, Multi-Cure Glass Ionomer Band Cement, and Transbond Plus Light Cure Band Adhesive) were prepared and the samples were extracted in 3 mL of Basal Medium Eagle with 10% newborn calf serum for 24 hours. The L929 cells were plated (25,000 cells/mL) in wells of 96-well dishes and maintained in a humidified incubator for 24 hours at 37 degrees C, 5% CO(2), and 95% air. After 24-hour incubation of the cells, the incubation medium was replaced by the immersed medium in which the samples were stored. Then L929 cells were incubated in contact with eluates for 24 hours. The cell mitochondrial activity was evaluated by the methyltetrazolium test. Twelve wells were used for each specimen, and methyltetrazolium tests were applied two times. The data were statistically analyzed using one-way analysis of variance and Tukey Honestly Significantly Different tests. Results with L929 fibroblasts demonstrated that all freshly prepared resin-modified orthodontic band adhesive materials reduced vital cell numbers (P > .05), in comparison to the control group. Our data demonstrate that all materials showed significant cytotoxicity compared to the control group. The results indicate that all materials showed significant cytotoxicity compared to the control group, and further studies using different test methods are needed for all resin-modified orthodontic band adhesives.

Analogues of the epoxy resin monomer diglycidyl ether of bisphenol F: effects on contact allergenic potency and cytotoxicity.

PubMed

O'Boyle, Niamh M; Delaine, Tamara; Luthman, Kristina; Natsch, Andreas; Karlberg, Ann-Therese

2012-11-19

Diglycidyl ethers of bisphenol A (DGEBA) and bisphenol F (DGEBF) are widely used as components in epoxy resin thermosetting products. They are known to cause occupational and nonoccupational allergic contact dermatitis. The aim of this study is to investigate analogues of DGEBF with regard to contact allergy and cytotoxicity. A comprehensive knowledge of the structural features that contribute to the allergenic and cytotoxic effects of DGEBF will guide the development of future novel epoxy resin systems with reduced health hazards for those coming into contact with them. It was found that the allergenic effects of DGEBF were dependent on its terminal epoxide groups. In contrast, it was found that the cytotoxicity in monolayer cell culture was dependent not only on the presence of epoxide groups but also on other structural features.

Synaptic plasticity and gravity: Ultrastructural, biochemical and physico-chemical fundamentals

NASA Astrophysics Data System (ADS)

Rahmann, H.; Slenzka, K.; Körtje, K. H.; Hilbig, R.

On the basis of quantitative disturbances of the swimming behaviour of aquatic vertebrates (``loop-swimming'' in fish and frog larvae) following long-term hyper-g-exposure the question was raised whether or not and to what extent changes in the gravitational vector might influence the CNS at the cellular level. Therefore, by means of histological, histochemical and biochemical analyses the effect of 2-4 x g for 9 days on the gross morphology of the fish brain, and on different neuronal enzymes was investigated. In order to enable a more precise analysis in future-μg-experiments of any gravity-related effects on the neuronal synapses within the gravity-perceptive integration centers differentiated electron-microscopical and electronspectroscopical techniques have been developed to accomplish an ultrastructural localization of calcium, a high-affinity Ca2+-ATPase, creatine kinase and cytochrome oxidase. In hyper-g animals vs. 1-g controls, a reduction of total brain volume (15 %), a decrease in creatine kinase activity (20 %), a local increase in cytochrome oxidase activity, but no differences in Ca2+/Mg2+-ATPase activities were observed. Ultrastructural peculiarities of synaptic contact formation in gravity-related integration centers (Nucleus magnocellularis) were found. These results are discussed on the basis of a direct effect of hyper-gravity not only on the gravity-sensitive neuronal integration centers but possibly also on the physico-chemical properties of the lipid bilayer of neuronal membranes in general.

Modification of the fluorescent antibody virus neutralisation test--elimination of the cytotoxic effect for the detection of rabies virus neutralising antibodies.

PubMed

Bedeković, Tomislav; Lemo, Nina; Lojkić, Ivana; Mihaljević, Zeljko; Jungić, Andreja; Cvetnić, Zeljko; Cač, Zeljko; Hostnik, Peter

2013-04-01

The virus neutralisation test is used for the quantitation of specific antibodies in serum samples. However, the success of the test depends on the quality of samples. In the case of poor quality samples, a cytotoxic effect can be observed and the results of the test can be compromised. Additionally, the cytotoxic effect limits the use of different substances, such as muscle extract or liquid from thoracic cavity (thoracic liquid), as a sample for the detection of rabies virus neutralising antibodies in the follow-up of fox oral vaccination campaigns. To eliminate the cytotoxic effect, a modified fluorescent antibody virus neutralisation (mFAVN) test was developed and evaluated. In the mFAVN test, inocula were removed after a 1h and the cytotoxic effect was prevented. According to the results obtained, the specificity of the mFAVN test compared to the FAVN test was 88.8% and the sensitivity was 94.4%. The diagnostic validity of the test was 0.99 (CI=0.98-1.00). To evaluate the possibility of using muscle extract and thoracic liquid as samples for the virus neutralisation test, 102 sera, muscle extract and thoracic liquid samples of dog origin were tested with the mFAVN test. The correlation between sera and muscle extracts was 87.9% (r=0.88, p<0.001). The correlation between sera and thoracic liquid was 94.2% (r=0.94, p<0.001). These findings indicated that both muscle extract and thoracic liquid could be used as samples for detection of rabies virus neutralising antibodies in the follow-up of oral vaccination campaigns. To evaluate the level of elimination of the cytotoxic effect, the 102 samples of sera, muscle extracts and thoracic liquid of dog origin were also tested in parallel using the mFAVN and FAVN tests. In the mFAVN test, no instance of cytotoxic effect was observed in the cells. In the FAVN test, two sera (1.9%), 35 muscle extracts (34.3%) and 56 thoracic liquid samples (54.9%) showed cytotoxic effect. The results of this study strongly suggest that

Cytotoxic and radioprotective effects of Podophyllum hexandrum.

PubMed

Shukla, Sandeep Kumar; Chaudhary, Pankaj; Prem Kumar, Indracanti; Afrin, Farhat; Puri, Satish Chandra; Qazi, Ghulam Nabi; Sharma, Rakesh Kumar

2006-07-01

Podophyllum hexandrum, a herb thriving in Himalayas has already been reported to exhibit antitumor and radioprotective properties. Present study was undertaken to unravel the possible mechanism responsible for the cytotoxic and radioprotective properties of REC-2001, a fraction isolated from the rhizome of P. hexandrum using murine peritoneal macrophages and plasmid DNA as model systems. Cell death, levels of intracellular reactive oxygen species (ROS) and apoptosis were studied employing trypan blue exclusion assay, dichlorofluorescein diacetate and DNA fragmentation assay, respectively. Superoxide anions, hydroxyl radicals and DNA damage were estimated following nitroblue tetrazolium, 2-deoxyribose degradation and plasmid DNA relaxation assays, respectively. Pre-irradiation administration of REC-2001 to peritoneal macrophages in the concentration range of 25-200μg/ml significantly reduced radiation induced ROS generation, DNA damage, apoptosis and cell killing in comparison to radiation control group indicating radioprotective potential. Studies with plasmid DNA indicated the ability of REC-2001 to inhibit 20Gy induced single and double strand breaks further supporting the antioxidative potential. However, REC-2001 in a dose-dependent fashion induced cell death, ROS and DNA fragmentation indicating the cytotoxic nature. REC-2001, in presence of 100μM copper sulfate, generated significant amount of hydroxyl radicals and superoxide anions indicating ability to act as a pro-oxidant in presence of metal ions. The superoxide anion generation was found to be sensitive to metal chelators like EDTA and deferoxamine mesylate (DFR). These results suggest that the ability of REC-2001 to act as a pro-oxidant in presence of metal ions and antioxidant in presence of free radicals might be responsible for cytotoxic and radioprotective properties.

Demonstration of a focused ion-beam cross-sectioning technique for ultrastructural examination of resin-dentin interfaces.

PubMed

Van Meerbeek, B; Conn, L J; Duke, E S; Schraub, D; Ghafghaichi, F

1995-03-01

focused ion-beam (FIB) etching, commonly used as a cross-sectioning technique for failure analysis of semiconductor devices, has recently been applied to biological tissues to expose their ultrastructure for examination. It was the aim of this investigation to determine the practical utility of FIB to cross-section resin-dentin interfaces in order to morphologically evaluate the completeness of resin penetration into the exposed collagen scaffold at the resin-dentin bond interface. Two representative commercially available dentin adhesive systems were bonded to mid-coronal dentin. After appropriate fixation and dehydration of the resin-bonded dentin samples, a scanned focused ion-beam of a few tens of nano-meters in diameter was used to cross=section the resin-dentin interface. Examination of the interfacial ultrastructure was accomplished using a field-emission SEM. Results indicate possible artifact production at the cross-sectioned interface, hiding its actual ultrastructure, probably due to a heat-effect with possible recrystallization. Further studies of FIB are needed to optimize its usefulness for resin-dentin interface examinations and other biological tissue applications. Complete resin saturation of the demineralized dentin surface-layer has been claimed to be the key factor for a long-lasting resin-dentin bond. A "clean" artifact-free micro-cross-sectioning technique may provide indisputable ultra-structural information about the depth of resin penetration into the demineralized zone. Such a test would be useful in the development of dentin adhesive systems.

Bisphenol A-induced ultrastructural changes in the testes of common marmoset

PubMed Central

Vijaykumar, Tushara; Singh, Dipty; Vanage, Geeta R.; Dhumal, Rohit V.; Dighe, Vikas D.

2017-01-01

Background & objectives: Bisphenol A (BPA) is an endocrine disruptor that is widely used in the manufacture of polycarbonate plastics, epoxy resins and dental sealants. It is known to have adverse effects on spermatogenesis in rodents. This study was aimed to evaluate the effects of BPA in adult common marmoset owing to its similarities with human spermatogenesis. Methods: Sixteen marmosets were divided into four groups (n=4 per group) and given oral doses of BPA (2.5, 12.5 and 25 μg/kg BW/day) for 70 days to cover two spermatogenic cycles, and the control group received only vehicle (honey). Testes were processed for histological and transmission electron microscopy studies. Results: Histology of the testis showed sloughing of germ cells into the lumen, increase in interstitial space and vacuolation of Sertoli cell cytoplasm. Ultrastructural analysis of the testis revealed several degenerative effects on the basement membrane, Sertoli cells, Leydig cells and other developing germ cells in the 12.5 and 25 μg/kg BW/day groups as compared to control. Interpretation & conclusions: The observed ultrastructural changes caused by BPA in testicular morphology might be indicative of a perturbed sperm production. Considering the genetic and spermatogenic similarities of common marmoset (Callithrix jacchus) and humans, the study findings are of significance. Further studies are, however, needed to elucidate the mechanism of action. PMID:29168469

Bisphenol A-induced ultrastructural changes in the testes of common marmoset.

PubMed

Vijaykumar, Tushara; Singh, Dipty; Vanage, Geeta R; Dhumal, Rohit V; Dighe, Vikas D

2017-07-01

Bisphenol A (BPA) is an endocrine disruptor that is widely used in the manufacture of polycarbonate plastics, epoxy resins and dental sealants. It is known to have adverse effects on spermatogenesis in rodents. This study was aimed to evaluate the effects of BPA in adult common marmoset owing to its similarities with human spermatogenesis. Sixteen marmosets were divided into four groups (n=4 per group) and given oral doses of BPA (2.5, 12.5 and 25 μg/kg BW/day) for 70 days to cover two spermatogenic cycles, and the control group received only vehicle (honey). Testes were processed for histological and transmission electron microscopy studies. Histology of the testis showed sloughing of germ cells into the lumen, increase in interstitial space and vacuolation of Sertoli cell cytoplasm. Ultrastructural analysis of the testis revealed several degenerative effects on the basement membrane, Sertoli cells, Leydig cells and other developing germ cells in the 12.5 and 25 μg/kg BW/day groups as compared to control. The observed ultrastructural changes caused by BPA in testicular morphology might be indicative of a perturbed sperm production. Considering the genetic and spermatogenic similarities of common marmoset (Callithrix jacchus) and humans, the study findings are of significance. Further studies are, however, needed to elucidate the mechanism of action.

Cytotoxic effects of octenidine mouth rinse on human fibroblasts and epithelial cells - an in vitro study.

PubMed

Schmidt, J; Zyba, V; Jung, K; Rinke, S; Haak, R; Mausberg, R F; Ziebolz, D

2016-01-01

This study compared the cytotoxicity of a new octenidine mouth rinse (MR) against gingival fibroblasts and epithelial cells with different established MRs. The following MRs were used: Octenidol (OCT), Chlorhexidine 0.2% (CHX), Listerine (LIS), Meridol (MER), Betaisodona (BET); and control (medium only). Human primary gingiva fibroblasts and human primary nasal epithelial cells were cultivated in cell-specific media (2 × 10(5) cells/ml) and treated with MR for 1, 5, and 15 min. Each test was performed 12 times. Metabolism activity was measured using a cytotoxicity assay. A cellometer analyzed cell viability, cell number, and cell diameter. The data were analyzed by two-way analysis of variance with subsequent Dunnett's test and additional t-tests. The cytotoxic effects of all MRs on fibroblasts and epithelial cells compared to the control depended on the contact time (p < 0.001). OCT and BET showed less influence on cell metabolism in fibroblasts than other MRs. OCT also demonstrated comparable but not significant results in epithelial cells (p > 0.005). Cell numbers of both cell types at all contact times revealed that OCT showed a less negative effect (p > 0.005), especially for epithelial cells compared to CHX after 15 min (p < 0.005). OCT and BET showed the best results for viability in fibroblasts (p > 0.005), but MER showed less influence than OCT in epithelial cells (p < 0.005). OCT is a potential alternative to CHX regarding cytotoxicity because of its lower cell-toxic effect against fibroblasts and epithelial cells.

Impact of calcium ion on cytotoxic effect of the boroxine derivative, K2[B3O3F4OH].

PubMed

Ivankovic, Sinisa; Stojkovic, Ranko; Maksimovic, Milka; Galic, Borivoj; Milos, Mladen

2016-01-01

The effect of Ca 2+ ions on the cytotoxic ability of boron heterocyclic compound dipotassium-trioxohydroxytetrafluorotriborate (K 2 [B 3 O 3 F 4 OH]), on in vitro tumor cells (mammary adenocarcinoma 4T1, melanoma B16F10 and squamous cell carcinoma SCCVII) and non-tumoral fibroblast cells (mouse dermal L929 and hamster lung V79) was examined. At small concentrations of Ca 2+ ions (0.42 mM), K 2 [B 3 O 3 F 4 OH] (3.85 mM) has a very strong cytotoxic effect on all cancer cells tested (89.1, 85.6 and 84.6%) and significantly less effect on normal cells (19.5 and 24.2%), respectively. Applying larger concentrations of Ca 2+ ions (9.42-72.42 mM), at the same concentration of K 2 [B 3 O 3 F 4 OH], no significant cytotoxic effect was detected on cancer cells and normal cells investigated. The selective ability of K 2 [B 3 O 3 F 4 OH], in the medium with a low concentration of Ca 2+ ions has a strong cytotoxic effect on cancer cells and very weak effect in normal cells, opens up the possibility of its application in antitumor therapy.

Protection of ultrastructure in chilling-stressed banana leaves by salicylic acid*

PubMed Central

Kang, Guo-zhang; Wang, Zheng-xun; Xia, Kuai-fei; Sun, Gu-chou

2007-01-01

Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope observation. Results: Pretreatment with 0.5 mmol/L SA under normal growth conditions (30/22 °C) by foliar spray and root irrigation resulted in many changes in ultrastructure of banana cells, such as cells separation from palisade parenchymas, the appearance of crevices in cell walls, the swelling of grana and stromal thylakoids, and a reduction in the number of starch granules. These results implied that SA treatment at 30/22 °C could be a type of stress. During 3 d of exposure to 7 °C chilling stress under low light, however, cell ultrastructure of SA-pretreated banana seedlings showed less deterioration than those of control seedlings (distilled water-pretreated). Conclusion: SA could provide some protection for cell structure of chilling-stressed banana seedling. PMID:17444604

Electron microscopy for ultrastructural analysis and protein localization in Saccharomyces cerevisiae

PubMed Central

Frankl, Andri; Mari, Muriel; Reggiori, Fulvio

2015-01-01

The yeast Saccharomyces cerevisiae is a key model system for studying of a multitude of cellular processes because of its amenability to genetics, molecular biology and biochemical procedures. Ultrastructural examinations of this organism, though, are traditionally difficult because of the presence of a thick cell wall and the high density of cytoplasmic proteins. A series of recent methodological and technical developments, however, has revived interest in morphological analyses of yeast (e.g. 123). Here we present a review of established and new methods, from sample preparation to imaging, for the ultrastructural analysis of S. cerevisiae. We include information for the use of different fixation methods, embedding procedures, approaches for contrast enhancement, and sample visualization techniques, with references to successful examples. The goal of this review is to guide researchers that want to investigate a particular process at the ultrastructural level in yeast by aiding in the selection of the most appropriate approach to visualize a specific structure or subcellular compartment. PMID:28357267

Ultrastructural and elemental analysis of sialoliths and their comparison with nephroliths.

PubMed

Rakesh, Nagaraju; Bhoomareddy Kantharaj, Yashoda Devi; Agarwal, Manjushree; Agarwal, Kunal

2014-02-01

Sialoliths are common in the submandibular gland and its duct system, although their exact cause of formation is still a matter of debate. The aims of this study were to: (a) analyze sialoliths ultrastructurally, and to determine the role of foreign bodies or organic materials in the formation of sialolith nuclei; and (b) compare nephroliths with sialoliths ultrastructurally. Three sialoliths and two nephroliths were analyzed ultrastructurally by a scanning electron microscope and X-ray diffractometer. The main structures of the sialoliths were found to be hydroxyapatite crystals. No organic cores were observed in the central parts of the sialoliths. In nephroliths, calcium oxalate, calcium phosphate, and struvite crystals were found. The energy-dispersive X-ray microanalysis found that sialoliths and nephroliths were predominantly composed of elements comprising calcium, phosphorous, magnesium, sodium, chloride, silicon, iron, and potassium. Sialoliths in the submandibular salivary glands might form secondary to sialadenitis, but not via a luminal organic nidus. © 2014 Wiley Publishing Asia Pty Ltd.

Nitric oxide releasing plasma polymer coating with bacteriostatic properties and no cytotoxic side effects.

PubMed

Michl, Thomas D; Coad, Bryan R; Doran, Michael; Osiecki, Michael; Kafshgari, Morteza Hasanzadeh; Voelcker, Nicolas H; Hüsler, Amanda; Vasilev, Krasimir; Griesser, Hans J

2015-04-25

We report a stable plasma polymer coating, using isopentyl nitrite as a volatile precursor, which releases nitric oxide at bacteriostatic concentrations when contacted with water, inhibiting bacterial growth without cytotoxic side effects to human mesenchymal stem/stromal cells.

In vitro cytotoxicity of iron oxide nanoparticles: effects of chitosan and polyvinyl alcohol as stabilizing agents

NASA Astrophysics Data System (ADS)

Tran, Phong A.; Nguyen, Hiep T.; Fox, Kate; Tran, Nhiem

2018-03-01

Iron oxide magnetic nanoparticles have significant potential in biomedical applications such as in diagnosis, imaging and therapeutic agent delivery. The choice of stabilizers and surface functionalization is important as it is known to strongly influence the cytotoxicity of the nanoparticles. The present study aimed at investigating the effects of surface charges on the cytotoxicity of iron oxide nanoparticles. We used a co-precipitation method to synthesize iron oxide nanoparticles which were then stabilized with either chitosan (CS) or polyvinyl alcohol (PVA) which have net positive charge and zero charge at physiological pH, respectively. The nanoparticles were characterized in terms of size, charges and chemical oxidation state. Cytotoxicity of the nanoparticles was assessed using mouse fibroblast cells and was correlated with surface charges of the nanoparticles and their aggregation.

Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hakim, Samer George, E-mail: samer.hakim@mkg-chir.mu-luebeck.de; Benedek, Geza Attila; Su Yuxiong

2012-03-15

Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary glandmore » function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.« less

Effect of prostaglandin E2 on cytotoxic activity and granzyme A protease release by murine adherent IL-2 activated killer cells.

PubMed

Vaillier, D; Daculsi, R; Gualde, N

1994-04-01

The effects of prostaglandin E2 (PGE2) have been studied on a highly purified population of murine IL-2 activated killer cells obtained by selecting plastic-adherent splenocytes (AK cells) after incubation with high doses of recombinant IL-2. AK cells were highly cytotoxic for YAC-1 target cells. The cytotoxic activity was detectable at one hour after initiation of the cytotoxic assay and then increased with time. Cytotoxic activity of AK cells was inhibited by the addition of PGE2 or forskolin during the cytotoxic assay. When AK cells were generated in the presence of PGE2, the yielding cytotoxic activity was lower than the one expressed by "regular" AK cells but were insensitive to the inhibitory effect of PGE2 even if their lytic capability was still suppressed by forskolin. The presence of PGE2 during the AK cell culture had no effect on the cellular proliferation. Moreover, using tetrazolium-based colorimetric assay which reflects the cellular activation, it was observed that AK cells cultured in presence of PGE2 had an increased capacity to cleave the tetrazolium salt to formazan. Since the cytotoxic activity of killer cells is related to expression of serine esterase enzymes we evaluated the effects of PGE2 on serine esterase (Granzyme A) release after one hour of incubation of AK cells either alone or in presence of PGE2, YAC-1 cells or both. We observed that (i) AK cells spontaneously release granzyme A, (ii) the level of granzyme A was significantly increased when AK cells were incubated either with YAC-1 cells or PGE2 but did not change when YAC-1 cells and PGE2 were both associated with AK cells.

Protective effects of Asian green vegetables against oxidant induced cytotoxicity

PubMed Central

Rose, Peter; Ong, Choon Nam; Whiteman, Matt

2005-01-01

AIM: To evaluate the antioxidant and phase II detoxification enzyme inducing ability of green leaf vegetables consumed in Asia. METHODS: The antioxidant properties of six commonly consumed Asian vegetables were determined using the ABTS, DPPH, deoxyribose, PR bleaching and iron- ascorbate induced lipid peroxidation assay. Induce of phase II detoxification enzymes was also determined for each respective vegetable extract. Protection against authentic ONOO- and HOCl mediated cytotoxicity in human colon HCT116 cells was determined using the MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide) viability assay. RESULTS: All of the extracts derived from green leaf vegetables exhibited antioxidant properties, while also having cytoprotective effects against ONOO- and HOCl mediated cytotoxicity. In addition, evaluation of the phase II enzyme inducing ability of each extract, as assessed by quinone reductase and glutathione-S-transferase activities, showed significant variation between the vegetables analyzed. CONCLUSION: Green leaf vegetables are potential sources of antioxidants and phase II detoxification enzyme inducers in the Asian diet. It is likely that consumption of such vegetables is a major source of beneficial phytochemical constituents that may protect against colonic damage. PMID:16437686

Light Affects the Chloroplast Ultrastructure and Post-Storage Photosynthetic Performance of Watermelon (Citrullus lanatus) Plug Seedlings

PubMed Central

Duan, Qingqing; Jiang, Wu; Ding, Ming; Lin, Ye; Huang, Danfeng

2014-01-01

Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] plug seedlings were stored at 15°C in the light at a photosynthetic photon flux density of 15 µmol·m−2·s−1 or in darkness for 6 days, to evaluate their chloroplast ultrastructure, and associated photosynthetic characteristics. Storage in the dark caused swelling, disordered granal arrangement, and starch grain disappearance in the chloroplasts. In contrast, the chloroplasts stored in the light were relatively normal. As a result, the light-stored seedlings had a significantly higher chlorophyll content, Fv/Fm, and Pn than did dark-stored seedlings. Regardless of whether the seedlings were stored in light or darkness, the Gs and Ls of the seedlings significantly decreased, while the Ci obviously increased when the Pn decreased after 6 days of storage. This result suggests that the decreased Pn is not solely a stomatal effect, as the effects on the chloroplasts contributed to this photosynthetic inhibition. Six days after transplanting, seedlings that were stored in the light or darkness for 2 or 4 days showed complete recovery of chloroplast ultrastructure, chlorophyll content, Fv/Fm, Gs and Pn. When the storage period increased to 6 days, the dark-stored seedlings had a significantly lower Fv/Fm and Pn than the light-stored and control seedlings 6 days after transplanting, which was mainly ascribed to incomplete recovery of chloroplast ultrastructure. Furthermore, the light-stored seedlings exhibited a significantly higher shoot dry weight during storage and a higher percentage dry weight increase after transplanting than the dark-stored seedlings. These effects were enhanced by prolonged storage (4 to 6 days). This study demonstrated that dim light during storage is beneficial for maintaining chloroplast ultrastructure as well as photosynthetic efficiency in watermelon seedlings, thus contributing to the rapid recovery of post-storage photosynthetic performance, which ensures the transplant quality

The chorion ultrastructure of ova of Lophius spp.

PubMed

Colmenero, A I; Tuset, V M; Fortuño, J-M; Sánchez, P

2015-06-01

The chorion surface ultrastructure of unfertilized eggs of black anglerfish Lophius budegassa and white anglerfish Lophius piscatorius was examined by scanning electron microscopy. Species-specific differences were observed. © 2015 The Fisheries Society of the British Isles.

Effects of Electroacupuncture on Interstitial Cells of Cajal (ICC) Ultrastructure and Connexin 43 Protein Expression in the Gastrointestinal Tract of Functional Dyspepsia (FD) Rats

PubMed Central

Zhang, Guoshan; Xie, Shen; Hu, Wei; Liu, Yuer; Liu, Mailan; Liu, Mi; Chang, Xiaorong

2016-01-01

Background Gastrointestinal motility disorder is the main clinical manifestation in functional dyspepsia (FD) patients. Electroacupuncture is effective in improving gastrointestinal motility disorder in FD; however, the underlying mechanism remains unclear. It has been demonstrated that interstitial cells of Cajal (ICC) are pacemaker cells in the gastrointestinal tract, and the pacemaker potential is transmitted to nearby cells through gap junctions between ICC or ICC and the smooth muscle. Therefore, this study aimed to assess the effects of electroacupuncture on ICC ultrastructure and expression of the gap junction protein connexin 43 (Cx43) in FD rats. Material/Methods The animals were randomized into 3 groups: control, model, and electroacupuncture. Electroacupuncture was applied at Zusanli (ST36) in the electroacupuncture group daily for 10 days, while no electroacupuncture was applied to model group animals. Results Ultrastructure of ICC recovered normally in gastric antrum and small intestine specimens was improved, with Cx43 expression levels in these tissues significantly increased in the electroacupuncture group compared with the model group. Conclusions These findings indicated that electroacupuncture is effective in alleviating ICC damage and reduces Cx43 levels in FD rats, and suggest that ICC and Cx43 are involved in electroacupuncture treatment in rats with FD to improve gastrointestinal motility disorders. PMID:27297942

Effects of Electroacupuncture on Interstitial Cells of Cajal (ICC) Ultrastructure and Connexin 43 Protein Expression in the Gastrointestinal Tract of Functional Dyspepsia (FD) Rats.

PubMed

Zhang, Guoshan; Xie, Shen; Hu, Wei; Liu, Yuer; Liu, Mailan; Liu, Mi; Chang, Xiaorong

2016-06-14

BACKGROUND Gastrointestinal motility disorder is the main clinical manifestation in functional dyspepsia (FD) patients. Electroacupuncture is effective in improving gastrointestinal motility disorder in FD; however, the underlying mechanism remains unclear. It has been demonstrated that interstitial cells of Cajal (ICC) are pacemaker cells in the gastrointestinal tract, and the pacemaker potential is transmitted to nearby cells through gap junctions between ICC or ICC and the smooth muscle. Therefore, this study aimed to assess the effects of electroacupuncture on ICC ultrastructure and expression of the gap junction protein connexin 43 (Cx43) in FD rats. MATERIAL AND METHODS The animals were randomized into 3 groups: control, model, and electroacupuncture. Electroacupuncture was applied at Zusanli (ST36) in the electroacupuncture group daily for 10 days, while no electroacupuncture was applied to model group animals. RESULTS Ultrastructure of ICC recovered normally in gastric antrum and small intestine specimens was improved, with Cx43 expression levels in these tissues significantly increased in the electroacupuncture group compared with the model group. CONCLUSIONS These findings indicated that electroacupuncture is effective in alleviating ICC damage and reduces Cx43 levels in FD rats, and suggest that ICC and Cx43 are involved in electroacupuncture treatment in rats with FD to improve gastrointestinal motility disorders.

A Tetrameric Peptide Derived from Bovine Lactoferricin Exhibits Specific Cytotoxic Effects against Oral Squamous-Cell Carcinoma Cell Lines

PubMed Central

Solarte, Víctor A.; Rosas, Jaiver E.; Rivera, Zuly J.; Arango-Rodríguez, Martha L.; García, Javier E.; Vernot, Jean-Paul

2015-01-01

Several short linear peptides derived from cyclic bovine lactoferricin were synthesized and tested for their cytotoxic effect against the oral cavity squamous-cell carcinoma (OSCC) cell lines CAL27 and SCC15. As a control, an immortalized and nontumorigenic cell line, Het-1A, was used. Linear peptides based on the RRWQWR core sequence showed a moderate cytotoxic effect and specificity towards tumorigenic cells. A tetrameric peptide, LfcinB(20–25)4, containing the RRWQWR motif, exhibited greater cytotoxic activity (>90%) in both OSCC cell lines compared to the linear lactoferricin peptide or the lactoferrin protein. Additionally, this tetrameric peptide showed the highest specificity towards tumorigenic cells among the tested peptides. Interestingly, this effect was very fast, with cell shrinkage, severe damage to cell membrane permeability, and lysis within one hour of treatment. Our results are consistent with a necrotic effect rather than an apoptotic one and suggest that this tetrameric peptide could be considered as a new candidate for the therapeutic treatment of OSCC. PMID:26609531

Evaluation of the cytotoxic and antimutagenic effects of biflorin, an antitumor 1,4 o-naphthoquinone isolated from Capraria biflora L.

PubMed

Vasconcellos, Marne C; Moura, Dinara J; Rosa, Renato M; Machado, Miriana S; Guecheva, Temenouga N; Villela, Izabel; Immich, Bruna F; Montenegro, Raquel C; Fonseca, Aluísio M; Lemos, Telma L G; Moraes, Maria Elisabete A; Saffi, Jenifer; Costa-Lotufo, Letícia V; Moraes, Manoel O; Henriques, João A P

2010-10-01

Biflorin is a natural quinone isolated from Capraria biflora L. Previous studies demonstrated that biflorin inhibits in vitro and in vivo tumor cell growth and presents potent antioxidant activity. In this paper, we report concentration-dependent cytotoxic, genotoxic, antimutagenic, and protective effects of biflorin on Salmonella tiphymurium, yeast Saccharomyces cerevisiae, and V79 mammalian cells, using different approaches. In the Salmonella/microsome assay, biflorin was not mutagenic to TA97a TA98, TA100, and TA102 strains. However, biflorin was able to induce cytotoxicity in haploid S. cerevisiae cells in stationary and exponential phase growth. In diploid yeast cells, biflorin did not induce significant mutagenic and recombinogenic effects at the employed concentration range. In addition, the pre-treatment with biflorin prevented the mutagenic and recombinogenic events induced by hydrogen peroxide (H(2)O(2)) in S. cerevisiae. In V79 mammalian cells, biflorin was cytotoxic at higher concentrations. Moreover, at low concentrations biflorin pre-treatment protected against H(2)O(2)-induced oxidative damage by reducing lipid peroxidation and DNA damage as evaluated by normal and modified comet assay using DNA glycosylases. Our results suggest that biflorin cellular effects are concentration dependent. At lower concentrations, biflorin has significant antioxidant and protective effects against the cytotoxicity, genotoxicity, mutagenicity, and intracellular lipid peroxidation induced by H(2)O(2) in yeast and mammalian cells, which can be attributed to its hydroxyl radical-scavenging property. However, at higher concentrations, biflorin is cytotoxic and genotoxic.

Participation of MT3 melatonin receptors in the synergistic effect of melatonin on cytotoxic and apoptotic actions evoked by chemotherapeutics.

PubMed

Pariente, Roberto; Bejarano, Ignacio; Espino, Javier; Rodríguez, Ana B; Pariente, José A

2017-11-01

Melatonin has antitumor activity via several mechanisms including its antiproliferative and proapoptotic effects in addition to its potent antioxidant actions. Therefore, melatonin may be useful in the treatment of tumors in association with chemotherapy drugs. This study was performed to study the role of melatonin receptors on the cytotoxicity and apoptosis induced by the chemotherapeutic agents cisplatin and 5-fluorouracil in two tumor cell lines, such as human colorectal cancer HT-29 cells and cervical cancer HeLa cells. We found that both melatonin and the two chemotherapeutic agents tested induced a decrease in HT-29 and HeLa cell viability. Furthermore, melatonin significantly increased the cytotoxic effect of chemotherapeutic agents, particularly, in 5-fluorouracil-challenged cells. Stimulation of cells with either of the two chemotherapeutic agents in the presence of melatonin further increased caspase-3 activation. Concomitant treatments with melatonin and chemotherapeutic agents augmented the population of apoptotic cells compared to the treatments with chemotherapeutics alone. Blockade of MT1 and/or MT2 receptors with luzindole or 4-P-PDOT was unable to reverse the enhancing effects of melatonin on both cytotoxicity, caspase-3 activation and the amount of apoptotic cells evoked by the chemotherapeutic agents, whereas when MT3 receptors were blocked with prazosin, the synergistic effect of melatonin with chemotherapy on cytotoxicity and apoptosis was reversed. Our findings provided evidence that in vitro melatonin strongly enhances chemotherapeutic-induced cytotoxicity and apoptosis in two tumor cell lines, namely HT-29 and HeLa cells and, this potentiating effect of melatonin is mediated by MT3 receptor stimulation.

In Vivo Effect of Calcium Hydroxide and Resin-modified Glass Ionomer Cement on Carious Dentin in Young Permanent Molars: An Ultrastructural and Macroscopic Study.

PubMed

Opal, Shireen; Garg, Shalini; Sharma, Deepak; Dhindsa, Abhishek; Jatana, Isha

2017-01-15

The purpose of this study was to evaluate macroscopically and ultrastructurally the effect of calcium hydroxide cement (CH) and resin-modified glass ionomer cement (RMGIC) compared with gutta percha (control) as a lining material on carious dentin after partial caries removal and sealing. Twenty-seven permanent molars with deep carious lesions underwent partial caries removal with the application of CH, RMGIC, or gutta percha (control) and were then sealed for three months. After a partial caries removal and sealing period, the dentin was macroscopically assessed (for color, consistency, and humidity) and further analyzed by scanning electron microscope to assess the ultrastructural changes in dentin (lumen size, mineralization of tubules, occlusion of tubules by cements, and bacterial ingress). The effect of treatment in each group was statistically analyzed. Dentin darkening and hardening were observed after the sealing period in all groups. However, there was no difference in the color after treatment among the three groups. It was observed that RMGIC showed a significant reduction in the size of the lumen compared to CH and the control. Partial caries removal and sealing resulted in dentin hardening, darkening, and dentin remineralization, irrespective of the dentin protection used.

The effect of propofol on plasma membrane ultrastructure in the intact cells

NASA Astrophysics Data System (ADS)

Jin, Weixiang; Pralle, Arnd

The mechanism of general anesthesia is still unknown. One drug used for human anesthesia, propofol, has been shown to interact with some ligand gated ion-channels, but also easily dissolves in the lipid bilayer and alters fluidity. Which mechanism dominates or even how anesthesia arises are unclear. We study the influence of propofol on plasma membrane (PM) ultrastructure in intact cells. In the PM, transient submicroscopic nanodomains form by interactions between lipid-acyl-chains or lipid head groups, stabilized by cholesterol. In addition, membrane cytoskeleton further regulates the nanodomains, which then regulate signaling. We study transient propofol effects on these domains from low to clinically relevant propofol concentrations by analyzing diffusion of GFP-tagged outer leaflet/inner leaflet membrane proteins. Using bimFCS we measure diffusion on multiple length scales simultaneously. We observe that at low propofol concentrations, the nanodomains trap GPI-mGFP less, consistent with studies showing that propofol decreases the phase transition temperature of membrane derived vesicles. Interestingly, at clinical relevant concentrations of propofol, the nanodomains trap GPI-mGFP more strongly. This is only observed at 37C. By inhibiting myosin activity or actin filaments (de-)polymerization, we find that the activity of actin filaments further alters the behavior of cholesterol nanodomains due to propofol. We compare the effect of propofol and its analog confirming specificity.

Cytotoxic and genotoxic effects of defence secretion of Ulomoides dermestoides on A549 cells.

PubMed

Crespo, Rosana; Villaverde, M Luciana; Girotti, Juan R; Güerci, Alba; Juárez, M Patricia; de Bravo, Margarita G

2011-06-14

Ulomoides dermestoides (Fairmaire, 1893) is a cosmopolitan tenebrionid beetle reared by Argentine people who consume them alive as an alternative medicine in the treatment of different illnesses such as asthma, Parkinson's, diabetes, arthritis, HIV and specially cancer. To evaluate the cytotoxicity and DNA damage of the major volatile components released by Ulomoides dermestoides on human lung carcinoma epithelial cell line A549. The defence compounds of Ulomoides dermestoides were extracted with dichloromethane and analyzed and quantified by capillary gas chromatography. The toxicity effects of the beetle's extract against A549 cell line were evaluated. Cytotoxicity was evaluated by MTT test and Trypan blue assay and genotoxicity was evaluated by the comet assay. The synthetic compounds, individually or combined, were also tested in A549 cells and normal mononuclear human cells. The defence compounds of Ulomoides dermestoides extracted with dichloromethane (methyl-1,4-benzoquinones, ethyl-1,4-benzoquinones and 1-pentadecene as major components) showed cytotoxic activity on A549 cells demonstrated by MTT test and Trypan blue assay, with IC(50) values of 0.26equivalent/ml and 0.34equivalent/ml, respectively (1equivalent=amount of components extracted per beetle). The inhibition of A549 cell proliferation with the synthetic blend (1,4-benzoquinone and 1-pentadecene) or 1,4-benzoquinone alone was similar to that obtained with the insect extract. 1-Pentadecene showed no inhibitory effect. Low doses of insect extract or synthetic blend (0.15equivalent/ml) inhibited mononuclear cell proliferation by 72.2±2.7% and induced significant DNA damage both in tumor and mononuclear cells. Results of this study demonstrated that defence compounds of Ulomoides dermestoides reduced cell viability and induced DNA damage. We also concluded that the insect benzoquinones are primarily responsible for inducing cytotoxicity and genotoxicity in culture cells. Copyright © 2011 Elsevier

Effect of electrocautery on endothelial integrity of the internal thoracic artery: ultrastructural analysis with transmission electron microscopy.

PubMed

Onan, Burak; Yeniterzi, Mehmet; Onan, Ismihan Selen; Ersoy, Burak; Gonca, Suheyla; Gelenli, Elif; Solakoglu, Seyhun; Bakir, Ihsan

2014-10-01

The internal thoracic artery (ITA) is typically harvested from the chest wall by means of conventional electrocautery. We investigated the effects of electrocautery on endothelial-cell and vessel-wall morphology at the ultrastructural level during ITA harvesting. Internal thoracic artery specimens from 20 patients who underwent elective coronary artery bypass grafting were investigated in 2 groups. The ITA grafts were sharply dissected with use of a scalpel and clips in the control group (n=10) and were harvested by means of electrocautery in the study group (n=10). Each sample was evaluated for intimal, elastic-tissue, muscular-layer, and adventitial changes. Free flow was measured intraoperatively. Light microscopic examinations were performed after hematoxylin-eosin and Masson's trichrome staining. Transmission electron microscopy was used to evaluate ultrastructural changes in the endothelial cells and vessel walls of each ITA. In the sharp-dissection group, the endothelial surfaces were lined with normal amounts of original endothelium, endothelial cells were distinctly attached to the basal lamina, cytoplasmic organelles were evident, and intercellular junctional complexes were intact. Conversely, in the electrocautery group, the morphologic integrity of endothelial cells was distorted, with some cell separations and splits, contracted cells, numerous large cytoplasmic vacuoles, and no visible cytoplasmic organelles. The subendothelial layer exhibited disintegration. Free ITA flow was higher in the sharp-dissection group (P=0.04). The integrity of endothelial cells can be better preserved when the ITA is mobilized by means of sharp dissection, rather than solely by electrocautery; we recommend a combined approach.

Effect of Electrocautery on Endothelial Integrity of the Internal Thoracic Artery: Ultrastructural Analysis with Transmission Electron Microscopy

PubMed Central

Onan, Burak; Yeniterzi, Mehmet; Onan, Ismihan Selen; Ersoy, Burak; Gonca, Suheyla; Gelenli, Elif; Solakoglu, Seyhun

2014-01-01

The internal thoracic artery (ITA) is typically harvested from the chest wall by means of conventional electrocautery. We investigated the effects of electrocautery on endothelial-cell and vessel-wall morphology at the ultrastructural level during ITA harvesting. Internal thoracic artery specimens from 20 patients who underwent elective coronary artery bypass grafting were investigated in 2 groups. The ITA grafts were sharply dissected with use of a scalpel and clips in the control group (n=10) and were harvested by means of electrocautery in the study group (n=10). Each sample was evaluated for intimal, elastic-tissue, muscular-layer, and adventitial changes. Free flow was measured intraoperatively. Light microscopic examinations were performed after hematoxylin-eosin and Masson's trichrome staining. Transmission electron microscopy was used to evaluate ultrastructural changes in the endothelial cells and vessel walls of each ITA. In the sharp-dissection group, the endothelial surfaces were lined with normal amounts of original endothelium, endothelial cells were distinctly attached to the basal lamina, cytoplasmic organelles were evident, and intercellular junctional complexes were intact. Conversely, in the electrocautery group, the morphologic integrity of endothelial cells was distorted, with some cell separations and splits, contracted cells, numerous large cytoplasmic vacuoles, and no visible cytoplasmic organelles. The subendothelial layer exhibited disintegration. Free ITA flow was higher in the sharp-dissection group (P=0.04). The integrity of endothelial cells can be better preserved when the ITA is mobilized by means of sharp dissection, rather than solely by electrocautery; we recommend a combined approach. PMID:25425979

Localized Irradiation of Cell Membrane by Auger Electrons Is Cytotoxic Through Oxidative Stress-Mediated Nontargeted Effects.

PubMed

Paillas, Salomé; Ladjohounlou, Riad; Lozza, Catherine; Pichard, Alexandre; Boudousq, Vincent; Jarlier, Marta; Sevestre, Samuel; Le Blay, Marion; Deshayes, Emmanuel; Sosabowski, Jane; Chardès, Thierry; Navarro-Teulon, Isabelle; Mairs, Robert J; Pouget, Jean-Pierre

2016-09-10

We investigated whether radiation-induced nontargeted effects are involved in the cytotoxic effects of anticell surface monoclonal antibodies labeled with Auger electron emitters, such as iodine 125 (monoclonal antibodies labeled with (125)I [(125)I-mAbs]). We showed that the cytotoxicity of (125)I-mAbs targeting the cell membrane of p53(+/+) HCT116 colon cancer cells is mainly due to nontargeted effects. Targeted and nontargeted cytotoxicities were inhibited in vitro following lipid raft disruption with Methyl-β-cyclodextrin (MBCD) or filipin or use of radical oxygen species scavengers. (125)I-mAb efficacy was associated with acid sphingomyelinase activation and modulated through activation of the AKT, extracellular signal-related kinase ½ (ERK1/2), p38 kinase, c-Jun N-terminal kinase (JNK) signaling pathways, and also of phospholipase C-γ (PLC-γ), proline-rich tyrosine kinase 2 (PYK-2), and paxillin, involved in Ca(2+) fluxes. Moreover, the nontargeted response induced by directing 5-[(125)I]iodo-2'-deoxyuridine to the nucleus was comparable to that of (125)I-mAb against cell surface receptors. In vivo, we found that the statistical significance of tumor growth delay induced by (125)I-mAb was removed after MBCD treatment and observed oxidative DNA damage beyond the expected Auger electron range. These results suggest the involvement of nontargeted effects in vivo also. Low-energy Auger electrons, such as those emitted by (125)I, have a short tissue range and are usually targeted to the nucleus to maximize their cytotoxicity. In this study, we show that targeting the cancer cell surface with (125)I-mAbs produces a lipid raft-mediated nontargeted response that compensates for the inferior efficacy of non-nuclear targeting. Our findings describe the mechanisms involved in the efficacy of (125)I-mAbs targeting the cancer cell surface. Antioxid. Redox Signal. 25, 467-484.

Ultrastructure of canine vasoformative tumors.

PubMed

Madewell, B R; Griffey, S M; Munn, R J

1992-01-01

The transmission electron microscope was used to examine 20 spontaneous canine hemangiosarcomas or hemangiopericytomas in order to define their fine ultrastructural features, and to compare those features with descriptions of human counterpart neoplasms. From specimen to specimen the neoplasms examined showed considerable structural heterogeneity but, in composite, appeared similar to the prototype human tumors. These data suggest that the canine hemangiosarcoma and hemangiopericytoma might serve as comparative models for studies of the morphogenesis of vasoformative neoplasms.

Cytotoxic Effects of Dillapiole on Embryonic Development of Mouse Blastocysts in Vitro and in Vivo

PubMed Central

Chan, Wen-Hsiung

2014-01-01

We examined the cytotoxic effects of dillapiole, a phenylpropanoid with antileishmanial, anti-inflammatory, antifungal, and acaricidal activities, on the blastocyst stage of mouse embryos, subsequent embryonic attachment and outgrowth in vitro, and in vivo implantation via embryo transfer. Blastocysts treated with 2.5–10 μM dillapiole exhibited a significant increase in apoptosis and corresponding decrease in total cell number. Notably, the implantation success rates of blastocysts pretreated with dillapiole were lower than those of their control counterparts. Moreover, in vitro treatment with 2.5–10 μM dillapiole was associated with increased resorption of post-implantation embryos and decreased fetal weight. Our results collectively indicate that dillapiole induces apoptosis and retards early post-implantation development, both in vitro and in vivo. However, the extent to which this organic compound exerts teratogenic effects on early human development is not known at present. Further studies are required to establish effective protection strategies against the cytotoxic effects of dillapiole. PMID:24933639

In Vitro Comparison of Cytotoxic and Antibacterial Effects of 16 Commercial Toothpastes

PubMed Central

Ghapanchi, Jannan; Kamali, Fereshteh; Moattari, Afagh; Poorshahidi, Sara; Shahin, Esmaiel; Rezazadeh, Fahimeh; Khorshidi, Hooman; Jamshidi, Samira

2015-01-01

Background: Toothpastes are considered as one of the most common and usable cosmetic and hygienic materials. Such materials contain chemicals which may have an adverse effect on oral tissue in humans. The present study aimed to compare the toxic effect of current commercial toothpastes including Iranian products and imported types which are consumed globally on oral epithelial- and HeLa cells as well as to evaluate their antibacterial effect on Streptococcus mutans in Shiraz, Iran. Materials and Methods: In this experimental study, 16 types of commercial toothpastes were prepared, and their effect was determined on primer epithelial cells of the oral cavity and HeLa cells. Toothpastes anti streptococcal property and toxicity were examined in vitro in different intervals of 1, 2, and 5 min. Data collection and analysis were done using one-way analysis of variance. Results: All experimented toothpastes revealed variable toxic effects on cultured cells. Through an increase in the time of exposure with toothpastes, the toxicity of these materials substantially increased (P = 0.005). On the other hand, all tested toothpastes showed varying degrees of anti-streptococcal effect in the laboratory (P = 0.005). Conclusions: The most cytotoxic effect on primer epithelial cells of oral mucosa and HeLa cells, respectively, belongs to Bath, Daroogar2, Latifeh2, Crend, Sehat, Nasim and Aqua fresh toothpastes; however, the least cytotoxic effect on primer epithelial cells of oral mucosa and HeLa cells, respectively, belongs to Pronamel followed by Crest (sensitive), Close-up, Oral-B, Signal, Colgate, Paradent, and AME. PMID:25878477

Prolonged cytotoxic effect of colchicine released from biodegradable microspheres.

PubMed

Muvaffak, Asli; Gurhan, Ismet; Hasirci, Nesrin

2004-11-15

One the main problems of cancer chemotherapy is the unwanted damage to normal cells caused by the high toxicities of anticancer drugs. Any system of controlled drug delivery that would reduce the total amount of drug required, and thus reduce the side effects, would potentially help to improve chemotherapy. In this respect, biodegradable gelatin microspheres were prepared by water/oil emulsion polymerization and by crosslinking with glutaraldehyde (GTA) as the drug-carrier system. Microspheres were loaded with colchicine, a model antimitotic drug, which was frequently used as an antimitotic agent in cancer research involving cell cultures. Microsphere sizes, swelling and degradation properties, drug-release kinetics, and cytotoxities were studied. Swelling characteristics of microspheres changed upon changing GTA concentration. A decrease in swelling values was recorded as GTA crosslink density was increased. In vitro drug release in PBS (0.01M, pH 7.4) showed rapid colchicine release up to approximately 83% (at t = 92 h) for microspheres with low GTA (0.05% v/v), whereas a slower release profile (only approximately 39%) was obtained for microspheres with high GTA (0.50% v/v) content, for the same period. Cytotoxicity tests with MCF-7, HeLa and H-82 cancer cell lines showed that free colchicine was very toxic, showing an approximately 100% lethal effect in both HeLa and H-82 cell lines and more than 50% decrease in viability in MCF-7 cells in 4 days. Indeed, entrapped colchicine indicated similar initial high toxic effect on cell viability in MCF-7 cell line and this effect became more dominant as colchicine continued to be released from microspheres in the same period. In conclusion, the control of the release rate of colchicine from gelatin microspheres was achieved under in vitro conditions by gelatin through the alteration of crosslinking conditions. Indeed, the results suggested the potential application of gelatin microspheres crosslinked with GTA as a

Infrasound-induced hemodynamics, ultrastructure, and molecular changes in the rat myocardium.

PubMed

Pei, Zhaohui; Sang, Hanfei; Li, Ruiman; Xiao, Pingxi; He, Jiangui; Zhuang, Zhiqiang; Zhu, Miaozhang; Chen, Jingzao; Ma, Hong

2007-04-01

Recent interest in adverse effects of infrasound on organisms arises from health concerns. We assessed the association between infrasound exposure of 5 Hz at 130 dB and changes of cardiac ultrastructure and function in rats. Thirty-two Sprague-Dawley rats were randomized into control, 1, 7, and 14 days groups for 2 h of infrasound once daily according to planned schedules. Changes of cardiac ultrastructure, hemodynamics indices, intracellular Ca(2+) concentrations ([Ca(2+)](i)), and sarcoplasmic reticulum Ca(2+)-ATPase 2 (SERCA2) were detected. Heart rates in 1 day group were significantly increased compared with control group and no significant changes in other groups. Left ventricular systolic pressures were significantly increased with time. Left ventricular diastolic end pressure and maximum rising rates of left ventricular pressure (+dl/dt) were significantly increased in 7 and 14 days groups and not changed in 1 day group, compared with control group. Maximum dropping rates of left ventricular pressure (-dl/dt) were significantly decreased in 7 and 14 days groups and not changed in 1 day group, compared with control group. In heart cells, there were several swelled mitochondria in 1 day group, more swelled mitochondria in 7 days group, platelet aggregation in the intercellular substance in 14 days group. [Ca(2+)](i) were significantly increased with time. There was a significant increase in SERCA2 in 1 day group, while a significant decrease in 7 and 14 days groups, compared with control group. Infrasound of 5 Hz at 130 dB can damage cardiac ultrastructure and function. Changes of [Ca(2+)](i) and SERCA2 play an important role in the secondary cardiac damage. (c) 2007 Wiley Periodicals, Inc.

Differentiation of HL-60 cells distinguishes between cytostatic and cytotoxic effects of the alkylphospholipid ET-18-OCH3.

PubMed

Civoli, F; Pauig, S B; Daniel, L W

1996-01-01

The synthetic dialkylphospholipid 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3) inhibits growth of the acute myelogenous leukemia cell line HL-60. Incubation of HL-60 cells with demethyl-sulfoxide causes the cells to differentiate to a granulocyte-like phenotype and become quiescent. Incubation of the DMSO-treated cells with ET-18-OCH3 results in a reduction in cell numbers due to cytotoxicity. In contrast, treatment of undifferentiated HL-60 cells with lower concentrations of ET-18-OCH3 leads to growth inhibition. These data indicate that the model of differentiated HL-60 cells currently used for the study of resistance to growth inhibition is inappropriate. HL-60 cells can be used to measure growth inhibition and at higher doses cytotoxicity. However, the differentiated, nonproliferative, cells can only be used to measure direct cytotoxicity. Therefore, the results of studies directly comparing the effects of ET-18-OCH3 in proliferative HL-60 cells and quiescent DMSO-treated HL-60 cells should be reevaluated. An evaluation of the effects of low concentrations of ET-18-OCH3 (0.5-1.5 microM) in proliferative HL-60 cells indicated that ET-18-OCH3 was an effective cytostatic agent at nontoxic concentrations. In summary, studies on the mechanism of action of ET-18-OCH3, or related ether lipids, should carefully investigate differences in the effects at cytostatic versus cytotoxic concentrations.

Genotoxic and cytotoxic effects of different types of dental cement on normal cultured human lymphocytes.

PubMed

Bakopoulou, A; Mourelatos, D; Tsiftsoglou, A S; Giassin, N P; Mioglou, E; Garefis, P

2009-01-31

In this study we have investigated the genotoxic and cytotoxic effects of eluates derived from different types of commercially available dental cements, including glass ionomer cements (GICs) (Ketac Cem/3M ESPE and GC Fuji I/GC Corp), resin-modified glass ionomer cements (RM-GICs) (RelyX Luting/3M ESPE and Vitrebond/3M ESPE) and dual-cure resin cements (RCs) (Variolink II/ Ivoclar-Vivadent and Panavia F 2.0/Kuraray) on normal cultured human lymphocytes. Lymphocyte primary cultures obtained from blood samples of three healthy donors were exposed to serial dilutions of eluates derived from specimens of each material tested. Metaphases were induced with phytohaemagglutinin, collected after 72h treatment by use of colchicine and stained according to the fluorescence plus giemsa (FPG) procedure. Preparations were scored for sister chromatid exchange (SCE) and chromosomal aberrations (CAs), while the proliferation rate index (PRI) was also calculated. Our results show that eluates derived from the RM-GICs and RCs caused severe genotoxic effects by significantly increasing the frequencies of SCEs and CAs in cultures of peripheral blood lymphocytes and by decreasing the relevant PRI values in a dose-dependent manner, whereas the two GICs caused only minor cytogenetic effects. Eluates of the two RM-GICs (Vitrebond and RelyX) were also very cytotoxic, as the first serial dilutions of both materials caused a complete mitotic arrest in lymphocyte cultures. Overall, the degree of genotoxicity and cytotoxicity caused by dental cements decreased as follows: Viterbond>Rely X>Panavia F 2.0>Variolink II>Ketac Cem=GC Fuji I. These results indicate that different types of dental cement differ extensively in their genotoxic and cytotoxic potential and their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair. Although these results cannot be directly extrapolated to the clinical situation, the potential occurrence of adverse effects caused by the

Ultra-Structure database design methodology for managing systems biology data and analyses

PubMed Central

Maier, Christopher W; Long, Jeffrey G; Hemminger, Bradley M; Giddings, Morgan C

2009-01-01

Background Modern, high-throughput biological experiments generate copious, heterogeneous, interconnected data sets. Research is dynamic, with frequently changing protocols, techniques, instruments, and file formats. Because of these factors, systems designed to manage and integrate modern biological data sets often end up as large, unwieldy databases that become difficult to maintain or evolve. The novel rule-based approach of the Ultra-Structure design methodology presents a potential solution to this problem. By representing both data and processes as formal rules within a database, an Ultra-Structure system constitutes a flexible framework that enables users to explicitly store domain knowledge in both a machine- and human-readable form. End users themselves can change the system's capabilities without programmer intervention, simply by altering database contents; no computer code or schemas need be modified. This provides flexibility in adapting to change, and allows integration of disparate, heterogenous data sets within a small core set of database tables, facilitating joint analysis and visualization without becoming unwieldy. Here, we examine the application of Ultra-Structure to our ongoing research program for the integration of large proteomic and genomic data sets (proteogenomic mapping). Results We transitioned our proteogenomic mapping information system from a traditional entity-relationship design to one based on Ultra-Structure. Our system integrates tandem mass spectrum data, genomic annotation sets, and spectrum/peptide mappings, all within a small, general framework implemented within a standard relational database system. General software procedures driven by user-modifiable rules can perform tasks such as logical deduction and location-based computations. The system is not tied specifically to proteogenomic research, but is rather designed to accommodate virtually any kind of biological research. Conclusion We find Ultra-Structure offers

Primary adenocarcinomas of the human urinary bladder: histochemical, immunological and ultrastructural studies.

PubMed

Alroy, J; Roganovic, D; Banner, B F; Jacobs, J B; Merk, F B; Ucci, A A; Kwan, P W; Coon, J S; Miller, A W

1981-01-01

Neoplastic and non-neoplastic tissue specimens from ten patients with primary adenocarcinoma of the urinary bladder were examined. Most of these tumors were associated with either foci of transitional cell carcinoma and/or with glandular metaplasia of the bladder epithelium. The mucin produced by the neoplastic cells was PAS, alcian blue, mucicarmine, PB/KOH/PAS, and RPB/KOH/PAS-positive. ABH isoantigens of these tumors were not always deleted. Ultrastructurally, the neoplastic cells resembled goblet cells. Their plasma membrane had numerous microvilli with prominent glycocalyx. Proliferation and attenuation of tight junctions were noted. The gap junctions were few and small. Two types of desmosomes were found. The ultrastructural features of the neoplastic cells were attributed in part to the malignant transformation and in part to the direction of their differentiation. We have not observed any distinctive morphologic, histochemical, immunologic or ultrastructural features that might be diagnostic for these adenocarcinomas.

Effects of lipopolysaccharide on interleukin-2-induced cytotoxic activity of murine splenocyte cultures: role of prostaglandin E2 and interferons.

PubMed

Vaillier, D; Daculsi, R; Gualde, N

1992-01-01

Splenocytes cultured for 24 h in the presence of interleukin-2 (IL-2), lipopolysaccharide (LPS) or both together expressed a cytotoxic activity against the YAC-1 lymphoma cell line and to a lesser extent against P815 mastocytoma cells. The association of IL-2 and LPS had an additive effect on induction of cytotoxicity. The IL-2-induced cytotoxic activity lasted for the whole of the culture; however, the addition of LPS at the initiation of the culture increased the cytotoxic activity during its the early phase, the increment being followed by a fall of lytic activity after 72 h of culture. Assessment of interferon (IFN) in the culture supernatants showed (a) a production of IFN gamma by IL-2-supplemented cultures, (b) a more potent IFN production by cultures treated with IL-2 plus LPS (including 20% IFN alpha/beta, (c) and that indomethacin (1 microM) potentiated the effect of either IL-2 or LPS used alone but did not significantly increase the cytotoxic activity of cultures treated with IL-2 plus LPS (the one that produced a high level of IFN). When cultures were treated by an anti-IFN gamma antibody we observed no change in the cytotoxic activity; however, in the presence of anti-IFN alpha/beta serum the cytotoxic activity of cultures treated with IL-2 plus LPS was inhibited after 24 h but stimulated after 72 h. When cultures treated with IL-2 plus LPS were supplemented with both indomethacin and anti-IFN alpha/beta the cytotoxic activity assessed after 72 h of culture was maintained at the same level as that of IL-2-treated cultures, hence the fall after 72 h of the cytotoxicity of cultures initiated in the presence of LPS alone was affected by both the immune serum and the cyclooxygenase inhibitor. Altogether these data show that when splenocytes are cultured for more than 72 h in the presence of IL-2 and LPS their cytotoxic activity decreases, and it is likely that this diminution is linked to the endogenous production of prostaglandin E2 and INF alpha/beta.

Cytotoxic Effects of PEGylated Anti-EGFR Immunoliposomes Combined with Doxorubicin and Rhenium-188 Against Cancer Cells.

PubMed

Hsu, Wei-Chuan; Cheng, Chu-Nian; Lee, Te-Wei; Hwang, Jeng-Jong

2015-09-01

We aimed to construct epidermal growth factor receptor (EGFR)-targeting cetuximab-immunoliposomes (IL-C225) for targeted delivery of doxorubicin and rhenium-188 (Re-188) to EGFR(+) cancer cells. Synthesized IL-C225 was analyzed by dynamic light scattering, transmission electron microscopy, and matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy. Cell binding and internalization were examined using doxorubicin-loaded IL-C225 (DXR-IL-C225) with confocal microscopy. IL-C225 combined with doxorubicin and Re-188 ((188)Re-DXR-IL-C225) was synthesized, and the cytotoxic effects of (188)Re-DXR-IL-C225 were analyzed in EGFR(+) cancer cells using cell viability assays. IL-C225 bound to EGFR on A431 cancer cells and was rapidly internalized. Furthermore, IL-C225 localized within the tumor cells efficiently. (188)Re-DXR-IL-C225 exhibited outstanding cytotoxic effects against EGFR(+) cancer cells in vitro and showed superior cytotoxic effects compared to DXR-IL-C225 or (188)Re-IL-C225 alone. The new formulation of (188)Re-DXR-IL-C225 may be a potential theranostic vehicle for delivery of drugs in the treatment of EGFR-overexpressing human cancer. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Synergistic antitumor cytotoxic actions of ascorbate and menadione on human prostate (DU145) cancer cells in vitro: nucleus and other injuries preceding cell death by autoschizis.

PubMed

Gilloteaux, Jacques; Jamison, James M; Neal, Deborah; Summers, Jack L

2014-04-01

Scanning (SEM) and transmission electron microscopy (TEM) were used to characterize the cytotoxic effects of ascorbate (VC), menadione (VK3), or a VC:VK3 combination on a human prostate carcinoma cell line (DU145) following a 1-h vitamin treatment and a subsequent 24-h incubation in culture medium. Cell alterations examined by light and electron microscopy were treatment-dependent with VC + VK3 >VK3 > VC > Sham. Oxidative stress-induced damage was found in most organelles. This report describes injuries in the tumor cell nucleus (chromatin and nucleolus), mitochondria, endomembranes, lysosomal bodies (autophagocytoses) and inclusions. Morphologic alterations suggest that cytoskeleton damage is likely responsible for the superficial cytoplasmic changes, including major changes in cell shape and size and the self-excising phenomena. Unlike apoptotic bodies, the excised pieces contain ribonucleoproteins, but not organelles. These deleterious events cause a progressive, significant reduction in the tumor cell size. During nuclear alterations, the nuclei maintain their envelope during chromatolysis and karyolysis until cell death, while nucleoli undergo a characteristic segregation of their components. In addition, changes in fat and glycogen storage are consistent the cytotoxic and metabolic alterations caused by the respective treatments. All cellular ultrastructural changes are consistent with cell death by autoschizis and not apoptosis or other kinds of cell death.

Cytotoxic effects of 2-methoxyestradiol in the hepatocellular carcinoma cell line HepG2.

PubMed

El Naga, Reem N Abou; El-Demerdash, Ebtehal; Youssef, Samar S; Abdel-Naim, Ashraf B; El-Merzabani, Mahmoud

2009-01-01

The study was designed to examine the potential cytotoxicity of 2-methoxyestradiol (2ME2), a natural 17beta-estradiol metabolite, in hepatocellular carcinoma and the possible underlying mechanisms for this cytotoxicity. The cell line HepG2 was treated with different concentrations of 2ME2 for 48 and 72 h. Using the sulforhodamine B assay, HepG2 was sensitive to the cytotoxic effect of 2ME2. 2ME2 induced cell arrest at the G(2)/M phase and a significant high percentage of apoptotic cells compared to the control group. Also, 2ME2 induced a significant increase in caspase 9 enzymatic activity after 48 and 72 h of treatment compared with control values. The DNA laddering was observed only in cells treated for 72 h. Furthermore, 2ME2 induced a significant decrease in the expression levels of vascular endothelial growth factor (VEGF) gene compared to the control values. 2ME2 exerts cytotoxic activity in the HepG2 cell line by preferential cell blocking at the G(2)/M phase as well as induction of apoptosis as evidenced by increased caspase 9 enzymatic activity and observed DNA laddering in 2ME2-treated HepG2 cells. In addition, a reduction in hypervascularity is an important postulated mechanism as indicated by the significant reduction in the expression of VGEF, one of the most important angiogenic factors.

Titanium dioxide nanoparticles-mediated in vitro cytotoxicity does not induce Hsp70 and Grp78 expression in human bronchial epithelial A549 cells.

PubMed

Aueviriyavit, Sasitorn; Phummiratch, Duangkamol; Kulthong, Kornphimol; Maniratanachote, Rawiwan

2012-10-01

Titanium dioxide nanoparticles (TiO(2)NPs) are increasingly being used in various industrial applications including the production of paper, plastics, cosmetics and paints. With the increasing number of nano-related products, the concern of governments and the general public about the health and environmental risks, especially with regard to occupational and other environmental exposure, are gradually increasing. However, there is insufficient knowledge about the actual affects upon human health and the environment, as well as a lack of suitable biomarkers for assessing TiO(2)NP-induced cytotoxicity. Since the respiratory tract is likely to be the main exposure route of industrial workers to TiO(2)NPs, we investigated the cytotoxicity of the anatase and rutile crystalline forms of TiO(2)NPs in A549 cells, a human alveolar type II-like epithelial cell line. In addition, we evaluated the transcript and protein expression levels of two heat shock protein (HSP) members, Grp78 and Hsp70, to ascertain their suitability as biomarkers of TiO(2)NP-induced toxicity in the respiratory system. Ultrastructural observations confirmed the presence of TiO(2)NPs inside cells. In vitro exposure of A549 cells to the anatase or rutile forms of TiO(2)NPs led to cell death and induced intracellular ROS generation in a dose-dependent manner, as determined by the MTS and dichlorofluorescein (DCF) assays, respectively. In contrast, the transcript and protein expression levels of Hsp70 and Grp78 did not change within the same TiO(2)NPs dose range (25-500 μg/ml). Thus, whilst TiO(2)NPs can cause cytotoxicity in A549 cells, and thus potentially in respiratory cells, Hsp70 and Grp78 are not suitable biomarkers for evaluating the acute toxicological effects of TiO(2)NPs in the respiratory system.

Assessment of antibacterial and cytotoxic effects of orthodontic stainless steel brackets coated with different phases of titanium oxide: An in-vitro study.

PubMed

Baby, Roshen Daniel; Subramaniam, Siva; Arumugam, Ilakkiya; Padmanabhan, Sridevi

2017-04-01

Our objective was to assess the antibacterial and cytotoxic effects of orthodontic stainless steel brackets coated with different phases of photocatalytic titanium oxide. From a total sample of 115 brackets, 68 orthodontic stainless steel brackets were coated with titanium oxide using a radiofrequency magnetron sputtering machine. The coated brackets were then converted into 34 each of the anatase and rutile phases of titanium oxide. These brackets were subdivided into 4 groups for antibacterial study and 3 groups for cytotoxicity study. Brackets for the antibacterial study were assessed against the Streptococcus mutans species using microbiologic tests. Three groups for the cytotoxicity study were assessed using the thiazolyl tetrazolium bromide assay. The antibacterial study showed that both phases were effective, but the rutile phase of photocatalytic titanium oxide had a greater bactericidal effect than did the anatase phase. The cytotoxicity study showed that the rutile phase had a greater decrease in viability of cells compared with the anatase phase. It is recommended that orthodontic brackets be coated with the anatase phase of titanium oxide since they exhibited a significant antibacterial property and were only slightly cytotoxic. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Brenner tumor of the ovary: a correlative histologic, histochemical, immunohistochemical, and ultrastructural investigation.

PubMed

Santini, D; Gelli, M C; Mazzoleni, G; Ricci, M; Severi, B; Pasquinelli, G; Pelusi, G; Martinelli, G

1989-08-01

The histologic, histochemical, immunohistochemical, and ultrastructural features of Brenner tumor (BT) were studied. BT was compared with transitional bladder cells, and close similarities between the two tissues were identified. Abundant glycogen in all cellular layers, an alcianophilic/sialomucinic surface mucous coat, and argyrophilic cells characterized both BT and bladder epithelium. Immunohistochemically, chromogranin and neuron-specific enolase reactivity was observed in all cases examined. An additional relevant finding was the presence of serotonin-storing cells in both BT and urothelium. Moreover, carcinoembryonic antigen, epithelial membrane antigen, and keratin reaction were found in BT and urothelium, indicating an additional antigenic similarity. Additionally, malignant Brenner tumor was ultrastructurally found to share many common features with the bladder tissue. The distinct histochemical, ultrastructural, and antigenic pattern of BT, primarily of the transitional type, is emphasized.

Endosulfan decreases cytotoxic activity of nonspecific cytotoxic cells and expression of granzyme gene in Oreochromis niloticus.

PubMed

Téllez-Bañuelos, Martha Cecilia; Ortiz-Lazareno, Pablo Cesar; Jave-Suárez, Luis Felipe; Siordia-Sánchez, Victor Hugo; Bravo-Cuellar, Alejandro; Santerre, Anne; Zaitseva, Galina P

2014-05-01

The effect of the organochlorinated insecticide endosulfan, on the cytotoxic activity of Nile tilapia nonspecific cytotoxic cells (NCC) was assessed. Juvenile Nile tilapia were exposed to endosulfan (7 ppb) for 96 h and splenic NCC were isolated. Flow cytometric phenotyping of NCC was based on the detection of the NCC specific membrane signaling protein NCCRP-1 by using the monoclonal antibody Mab 5C6; granzyme expression was evaluated by quantitative RT-PCR. The cytotoxic activity of sorted NCC on HL-60 tumoral cells was assessed using propidium iodide (PI) staining of DNA in HL-60 nuclei, indicating dead cells. Nile tilapia splenic NCC had the ability to kill HL-60 tumoral cells, however, the exposure to endosulfan significantly reduced, by a 65%, their cytotoxic activity when using the effector:target ratio of 40:1. Additionally, the exposure to endosulfan tended to increase the expression of NCCRP-1, which is involved in NCC antigen recognition and signaling. Moreover, it decreased the expression of the granzyme gene in exposed group as compared with non-exposed group; however significant differences between groups were not detected. In summary, the acute exposure of Nile tilapia to sublethal concentration of endosulfan induces alteration in function of NCC: significant decrease of cytotoxic activity and a tendency to lower granzyme expression, severe enough to compromise the immunity of this species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cytotoxic constituents of Pachyrhizus tuberosus from Peruvian amazon.

PubMed

Leuner, Olga; Havlik, Jaroslav; Budesinsky, Milos; Vrkoslav, Vladimir; Chu, Jessica; Bradshaw, Tracey D; Hummelova, Jana; Miksatkova, Petra; Lapcik, Oldrich; Valterova, Irena; Kokoska, Ladislav

2013-10-01

Investigations into the chemical constituents of the seeds of the neglected tuber crop Pachyrhizus tuberosus (Leguminosae) resulted in the isolation of seven components: five rotenoids [12a-hydroxyerosone (1), 12a-hydroxydolineone (2), erosone (3), 12a-hydroxyrotenone (4) and rotenone (6)], a phenylfuranocoumarin [pachyrrhizine (5)] and an isoflavanone [neotenone (7)]. The compounds were isolated using several chromatography techniques and characterized and verified by NMR and HPLC/MS. The MTT assay was used to examine the selective cytotoxic effects of the methanolic P. tuberosus extract and isolated compounds in two human cancer cell lines [breast (MCF-7) and colorectal (HCT-116)] and in non-transformed human fibroblasts (MRC-5); IC50 values were calculated. The methanolic P. tuberosus extract displayed respectable cytotoxic effects against HCT-116 and MCF-7 cells with IC50 values of 7.3 and 6.3 microg/mL, respectively. Of the compounds, 6 exacted greatest cytotoxicity and selectivity towards the cancer cell lines tested, yielding IC50 values of 0.3 microg/mL against both MCF-7 and HCT-116 cells, and a 6-fold reduced activity against MRC-5 fibroblasts. Compound 4 also demonstrated cytotoxicity against MCF-7 and HCT-116 (1.1 and 1.8 microg/mL, respectively), and reduced cytotoxicity towards MRC-5 cells (7.5 mirog/mL). The results revealed from the in vitro cytotoxic MTT assay are worthy of further antitumor investigation.

Effect of c-myc on the ultrastructural structure of cochleae in guinea pigs with noise induced hearing loss

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Yu; Zhong, Cuiping; Hong, Liu

2009-12-18

Noise over-stimulation may induce hair cells loss and hearing deficit. The c-myc oncogene is a major regulator for cell proliferation, growth, and apoptosis. However, the role of this gene in the mammalian cochlea is still unclear. The study was designed to firstly investigate its function under noise condition, from the aspect of cochlear ultrastructural changes. We had established the adenoviral vector of c-myc gene and delivered the adenovirus suspension into the scala tympani of guinea pigs 4 days before noise exposure. The empty adenoviral vectors were injected as control. Then, all subjects were exposed to 4-kHz octave-band noise at 110more » dB SPL for 8 h/day, 3 days consecutively. Auditory thresholds were assessed by auditory brainstem response, prior to and 7 days following noise exposure. On the seventh days after noise exposure, the cochlear sensory epithelia surface was observed microscopically and the cochleae were taken to study the ultrastructural changes. The results indicated that auditory threshold shift after noise exposure was higher in the ears treated with Ad.EGFP than that treated with Ad.c-myc-EGFP. Stereocilia loss and the disarrangement of outer hair cells were observed, with greater changes found in the Ad.EGFP group. Also, the ultrastructure changes were severe in the Ad.EGFP group, but not obvious in the Ad.c-myc-EGFP group. Therefore, c-myc gene might play an unexpected role in hearing functional and morphological protection from acoustic trauma.« less

Effects of total flavonoids of sea buckthorn ( Hippophae rhamnoides L.) on cytotoxicity of NK92-MI cells.

PubMed

Hou, Diandong; Wang, Decheng; Ma, Xiande; Chen, Wenna; Guo, Shengnan; Guan, Hongquan

2017-12-01

Sea buckthorn ( Hippophae rhamnoides L.) has multifarious medicinal properties including immunoregulatory effect. The total flavonoids of Hippophae rhamnoides L. (TFH) are the main active components isolated from berries of sea buckthorn. The aim of this study was to evaluate the effects of TFH on the cytotoxicity of NK92-MI cells and its possible mechanisms. NK92-MI cells were treated with TFH (2.5 or 5.0 mg/L) or phosphate-buffered saline (PBS) for 24 h, the cytotoxicity against K562 was detected by measuring the release of lactate dehydrogenase (LDH), expression levels of NCRs (NKp30, NKp44, NKp46) and NKG2D were detected by flow cytometry, and expression levels of perforin and granzyme B were detected by western blot. Cytokine Antibody Arrays with 80 cytokine proteins were used to profile the effect of TFH on cytokines. Western blot was adopted to detect the effects of TFH on STAT1, STAT4, and STAT5 signal pathway. Compared with the normal control group, TFH could significantly enhance NK92-MI cell cytotoxicity against K562 cells, upregulate expressions of NKp44, NKp46, perforin, and granzyme B. TFH could upregulate expressions of IL-1α, IL-2, IL-7, IL-15, CSF-2, CSF-3, MCP-1, MIG, IFN-γ, TNF-α, and TNF-β and downregulate expressions of IL-16, MIP-1β, CX3CL-1, and MIF. TFH could increase expressions of phospho-STAT1 and phospho-STAT5. The results suggest that TFH stimulated NK92-MI cells to activate and enhance cytotoxicity of NK92-MI cells.

The effect of glycosylation on cytotoxicity of Ibaraki virus nonstructural protein NS3

PubMed Central

URATA, Maho; WATANABE, Rie; IWATA, Hiroyuki

2015-01-01

The cytotoxicity of Ibaraki virus nonstructural protein NS3 was confirmed, and the contribution of glycosylation to this activity was examined by using glycosylation mutants of NS3 generated by site-directed mutagenesis. The expression of NS3 resulted in leakage of lactate dehydrogenase to the culture supernatant, suggesting the cytotoxicity of this protein. The lack of glycosylation impaired the transport of NS3 to the plasma membrane and resulted in reduced cytotoxicity. Combined with the previous observation that NS3 glycosylation was specifically observed in mammalian cells (Urata et al., Virus Research 2014), it was suggested that the alteration of NS3 cytotoxicity through modulating glycosylation is one of the strategies to achieve host specific pathogenisity of Ibaraki virus between mammals and vector arthropods. PMID:26178820

Cytotoxic effects of Pinus eldarica essential oil and extracts on HeLa and MCF-7 cell lines.

PubMed

Sarvmeili, Najmeh; Jafarian-Dehkordi, Abbas; Zolfaghari, Behzad

2016-12-01

Several attempts have so far been made in the search of new anticancer agents of plant origin. Some studies have reported that different species of Pine genus possess cytotoxic activities against various cancer cell lines. In the present study, we evaluated the cytotoxic effects of Pinus eldarica bark and leaf extracts or leaf essential oil on HeLa and MCF-7 tumor cell lines. Hydroalcoholic and phenolic extracts and the essential oil of plant were prepared. Total phenolic contents of the extracts were measured using Folin-Ciocalteu reagent. Essential oil components were determined by gas chromatography-mass spectroscopy (GC-MS). Cytotoxic activity of the extracts and essential oil against HeLa and MCF-7 tumor cell lines were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The polyphenolic content of hydroalcoholic and phenolic extracts of the bark and hydroalcoholic extract of the leaf were 48.31%, 47.2%, and 8.47%, respectively. According to the GC-MS analysis, the major components of the leaf oil of P. eldarica were: β -caryophyllene (14.8%), germacrene D (12.9%), α-terpinenyl acetate (8.15%), α -pinene (5.7%), and -α humulene (5.9%). Bark extracts and leaf essential oil of P. eldarica significantly reduced the viability of both HeLa and MCF-7 cells in a concentration dependent manner. However, leaf extract showed less inhibitory effects against both cell lines. The essential oil of P. eldarica was more cytotoxic than its hydroalcoholic and phenolic extracts. The terpenes and phenolic compounds were probably responsible for cytotoxicity of P. eldarica . Therefore, P. eldarica might have a good potential for active anticancer agents.

Cytotoxic effects of oosporein isolated from endophytic fungus Cochliobolus kusanoi

PubMed Central

Ramesha, Alurappa; Venkataramana, M.; Nirmaladevi, Dhamodaran; Gupta, Vijai K.; Chandranayaka, S.; Srinivas, Chowdappa

2015-01-01

In the present study, oosporein, a fungal toxic secondary metabolite known to be a toxic agent causing chronic disorders in animals, was isolated from fungus Cochliobolus kusanoi of Nerium oleander L. Toxic effects of oosporein and the possible mechanisms of cytotoxicity as well as the role of oxidative stress in cytotoxicity to Madin-Darby canine kidney kidney cells and RAW 264.7 splene cells were evaluated in vitro. Also to know the possible in vivo toxic effects of oosporein on kidney and spleen, Balb/C mouse were treated with different concentrations of oosporein ranging from 20 to 200 μM). After 24 h of exposure histopathological observations were made to know the effects of oosporein on target organs. Oosporein induced elevated levels of reactive oxygen species (ROS) generation and high levels of malondialdehyde, loss of mitochondrial membrane potential, induced glutathione hydroxylase (GSH) production was observed in a dose depended manner. Effects oosporein on chromosomal DNA damage was assessed by Comet assay, and increase in DNA damage were observed in both the studied cell lines by increasing the oosporein concentration. Further, oosporein treatment to studied cell lines indicated significant suppression of oxidative stress related gene (Superoxide dismutase1 and Catalase ) expression, and increased levels of mRNA expression in apoptosis or oxidative stress inducing genes HSP70, Caspase3, Caspase6, and Caspase9 as measured by quantitative real time-PCR assay. Histopathological examination of oosporein treated mouse kidney and splenocytes further revealed that, oosporein treated target mouse tissues were significantly damaged with that of untreated sam control mice and these effects were in directly proportional to the the toxin dose. Results of the present study reveals that, ROS is the principle event prompting increased oosporein toxicity in studied in vivio and in vitro animal models. The high previlance of these fungi in temperate climates further

Inhibition of heme oxygenase-1 enhances the cytotoxic effect of gemcitabine in urothelial cancer cells.

PubMed

Miyake, Makito; Fujimoto, Kiyohide; Anai, Satoshi; Ohnishi, Sayuri; Nakai, Yasushi; Inoue, Takeshi; Matsumura, Yoshiaki; Tomioka, Atsushi; Ikeda, Tomohiro; Okajima, Eijiro; Tanaka, Nobumichi; Hirao, Yoshihiko

2010-06-01

Elevated heme oxygenase-1 (HO-1) is associated with resistance to chemo- and radiotherapy through anti-apoptotic function. The present study evaluated whether the HO-1 inhibitor, zinc protoporphyrin IX (ZnPP), enhances the cytotoxic effect of gemcitabine in urothelial carcinoma (UC). The in vitro cytotoxic effect of combination treatment of gemcitabine and ZnPP on UC cells was examined. The in vivo growth inhibitory effects of intraperitoneal administration of gemcitabine and/or ZnPP on mouse subcutaneous tumours were examined. The apoptotic changes were analysed with the detection of DNA fragmentation and cleaved caspase-3. HO-1 was up-regulated by both gemcitabine and irradiation treatment in vitro. ZnPP sensitised the UC cells to both therapies. Enhanced apoptosis was induced by the ZnPP combined with gemicitabine. ZnPP enhanced the antitumour effect of gemcitabine in vivo along with decreased numbers of proliferating cells and increased numbers of apoptotic cells. These findings suggest that ZnPP combined with gemcitabine or irradiation therapy may be an effective therapeutic modality for UC patients.

Gold-Containing Indoles as Anti-Cancer Agents that Potentiate the Cytotoxic Effects of Ionizing Radiation

PubMed Central

Craig, Sandra; Gao, Lei; Lee, Irene; Gray, Thomas; Berdis, Anthony J.

2012-01-01

This report describes the design and application of several distinct gold-containing indoles as anti-cancer agents. When used individually, all gold-bearing compounds display cytostatic effects against leukemia and adherent cancer cell lines. However, two gold-bearing indoles show unique behavior by increasing the cytotoxic effects of clinically relevant levels of ionizing radiation. Quantifying the amount of DNA damage demonstrates that each gold-indole enhances apoptosis by inhibiting DNA repair. Both Au(I)-indoles were tested for inhibitory effects against various cellular targets including thioredoxin reductase, a known target of several gold compounds, and various ATP-dependent kinases. While neither compound significantly inhibits the activity of thioreoxin reductase, both showed inhibitory effects against several kinases associated with cancer initiation and progression. The inhibition of these kinases provides a possible mechanism for the ability of these Au(I)-indoles potentiate the cytotoxic effects of ionizing radiation. Clinical applications of combining Au(I)-indoles with ionizing radiation are discussed as a new strategy to achieve chemosensitization of cancer cells. PMID:22289037

Hematology, cytochemistry and ultrastructure of blood cells in fishing cat (Felis viverrina).

PubMed

Prihirunkit, Kreangsak; Salakij, Chaleow; Apibal, Suntaree; Narkkong, Nual Anong

2007-06-01

Hematological, cytochemical and ultrastructural features of blood cells in fishing cat (Felis viverrina) were evaluated using complete blood cell counts with routine and cytochemical blood stains, and scanning and transmission electron microscopy. No statistically significant difference was found in different genders of this animal. Unique features of blood cells in this animal were identified in hematological, cytochemical and ultrastructural studies. This study contributes to broaden hematological resources in wildlife animals and provides a guideline for identification of blood cells in the fishing cat.

Cytotoxicity of natural ginseng glycosides and semisynthetic analogues.

PubMed

Atopkina, L N; Malinovskaya, G V; Elyakov, G B; Uvarova, N I; Woerdenbag, H J; Koulman, A; Pras, N; Potier, P

1999-02-01

The cytotoxicity of natural glycosides from Ginseng, semisynthetic analogues and related triterpenes of the dammarane series, isolated from the leaves of the Far-East species of the genus Betula was studied in order to elucidate structure-activity relationships. Some of the compounds studied were active against the human lung carcinoma GLC4 and adenocarcinoma COLO 320 cell lines. The natural glycosides displayed the lowest cytotoxicity. The triterpenes of the dammarane series used as starting aglycones for semisynthetic derivatives were moderately cytotoxic. The dammarane triterpenes possessing keto groups and their semisynthetic glucosides were the most active compounds tested. Cytotoxic effects of the dammarane glucosides were inversely proportional both to the number of sugars attached to the aglycones and to the number of hydroxy groups of the aglycones. The type of side chain and the configuration of the hydroxy group at C-3 in aglycones did not have a significant influence on the cytotoxicity.

Cytotoxic effect of disulfiram/copper on human glioblastoma cell lines and ALDH-positive cancer-stem-like cells

PubMed Central

Liu, P; Brown, S; Goktug, T; Channathodiyil, P; Kannappan, V; Hugnot, J-P; Guichet, P-O; Bian, X; Armesilla, A L; Darling, J L; Wang, W

2012-01-01

Background: Glioblastoma multiforme (GBM) cells are resistant to anticancer drugs. Cancer stem cells (CSCs) are a key mediator of chemoresistance. We have reported that disulfiram (DS), an aldehyde dehydrogenase (ALDH) inhibitor, targets breast CSC-like cells. In this study, the effect of DS and combination of DS and gemcitabine (dFdC) on GBM cells and GBM stem-like cells was investigated. Methods: 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), combination index (CI)-isobologram, western blot, luciferase reporter gene assay, electrophoretic mobility-shift assay and ALDH analysis were used in this study. Results: Disulfiram is cytotoxic in GBM cell lines in a copper (Cu)-dependent manner. Disulfiram/copper enhances the cytotoxicity of dFdC. Combination index-isobologram analysis indicates a synergistic effect between DS/Cu and dFdC. Disulfiram/copper induces reactive oxygen species (ROS), activates JNK and p38 pathways and inhibits nuclear factor-kappa B activity in GBM cell lines. Disulfiram/copper may trigger intrinsic apoptotic pathway via modulation of the Bcl2 family. Disulfiram/copper abolishes stem-like cell population in GBM cell lines. Conclusion: Our findings indicate that the cytotoxicity of DS/Cu and the enhancing effect of DS/Cu on the cytotoxicity of dFdC in GBM stem-like cells may be caused by induction of ROS and inhibition of both ALDH and the NFkB pathway. Both DS and dFdC can traverse the blood–brain barrier. Further study may lead them into GBM chemotherapy. PMID:23033007

Gold Nanoparticles Cytotoxicity

NASA Astrophysics Data System (ADS)

Mironava, Tatsiana

Over the last two decades gold nanoparticles (AuNPs) have been used for many scientific applications and have attracted attention due to the specific chemical, electronic and optical size dependent properties that make them very promising agents in many fields such as medicine, imagine techniques and electronics. More specifically, biocompatible gold nanoparticles have a huge potential for use as the contrast augmentation agent in X-ray Computed Tomography and Photo Acoustic Tomography for early tumor diagnostic as well these nanoparticles are extensively researched for enhancing the targeted cancer treatment effectiveness such as photo-thermal and radiotherapy. In most biomedical applications biocompatible gold nanoparticles are labeled with specific tumor or other pathology targeting antibodies and used for site specific drug delivery. However, even though gold nanoparticles poses very high level of anti cancer properties, the question of their cytotoxicity ones they are released in normal tissue has to be researched. Moreover, the huge amount of industrially produced gold nanoparticles raises the question of these particles being a health hazard, since the penetration is fairly easy for the "nano" size substances. This study focuses on the effect of AuNPs on a human skin tissue, since it is fall in both categories -- the side effects for biomedical applications and industrial workers and users' exposure during production and handling. Therefore, in the present project, gold nanoparticles stabilized with the biocompatible agent citric acid were generated and characterized by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). The cytotoxic effect of AuNPs release to healthy skin tissue was modeled on 3 different cell types: human keratinocytes, human dermal fibroblasts, and human adipose derived stromal (ADS) cells. The AuNPs localization inside the cell was found to be cell type dependent. Overall cytotoxicity was found to be dependent

Effects of long-term salicylate administration on synaptic ultrastructure and metabolic activity in the rat CNS

PubMed Central

Yi, Bin; Hu, Shousen; Zuo, Chuantao; Jiao, Fangyang; Lv, Jingrong; Chen, Dongye; Ma, Yufei; Chen, Jianyong; Mei, Ling; Wang, Xueling; Huang, Zhiwu; Wu, Hao

2016-01-01

Tinnitus is associated with neural hyperactivity in the central nervous system (CNS). Salicylate is a well-known ototoxic drug, and we induced tinnitus in rats using a model of long-term salicylate administration. The gap pre-pulse inhibition of acoustic startle test was used to infer tinnitus perception, and only rats in the chronic salicylate-treatment (14 days) group showed evidence of experiencing tinnitus. After small animal positron emission tomography scans were performed, we found that the metabolic activity of the inferior colliculus (IC), the auditory cortex (AC), and the hippocampus (HP) were significantly higher in the chronic treatment group compared with saline group (treated for 14 days), which was further supported by ultrastructural changes at the synapses. The alterations all returned to baseline 14 days after the cessation of salicylate-treatment (wash-out group), indicating that these changes were reversible. These findings indicate that long-term salicylate administration induces tinnitus, enhanced neural activity and synaptic ultrastructural changes in the IC, AC, and HP of rats due to neuroplasticity. Thus, an increased metabolic rate and synaptic transmission in specific areas of the CNS may contribute to the development of tinnitus. PMID:27068004

Effects of retinoic acid-inducible gene-I-like receptors activations and ionizing radiation cotreatment on cytotoxicity against human non-small cell lung cancer in vitro.

PubMed

Yoshino, Hironori; Iwabuchi, Miyu; Kazama, Yuka; Furukawa, Maho; Kashiwakura, Ikuo

2018-04-01

Retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns and induce antiviral immune responses. Recent studies have demonstrated that RLR activation induces antitumor immunity and cytotoxicity against different types of cancer, including lung cancer. However a previous report has demonstrated that ionizing radiation exerts a limited effect on RLR in human monocytic cell-derived macrophages, suggesting that RLR agonists may be used as effective immunostimulants during radiation therapy. However, it is unclear whether ionizing radiation affects the cytotoxicity of RLR agonists against cancer cells. Therefore, in the present study the effects of cotreatment with ionizing radiation and RLR agonists on cytotoxicity against human non-small cell lung cancer cells A549 and H1299 was investigated. Treatment with RLR agonist poly(I:C)/LyoVec™ [poly(I:C)] exerted cytotoxic effects against human non-small cell lung cancer. The cytotoxic effects of poly(I:C) were enhanced by cotreatment with ionizing radiation, and poly(I:C) pretreatment resulted in the radiosensitization of non-small cell lung cancer. Furthermore, cotreatment of A549 and H1299 cells with poly(I:C) and ionizing radiation effectively induced apoptosis in a caspase-dependent manner compared with treatment with poly(I:C) or ionizing radiation alone. These results indicate that RLR agonists and ionizing radiation cotreatment effectively exert cytotoxic effects against human non-small cell lung cancer through caspase-mediated apoptosis.

Effects of retinoic acid-inducible gene-I-like receptors activations and ionizing radiation cotreatment on cytotoxicity against human non-small cell lung cancer in vitro

PubMed Central

Yoshino, Hironori; Iwabuchi, Miyu; Kazama, Yuka; Furukawa, Maho; Kashiwakura, Ikuo

2018-01-01

Retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns and induce antiviral immune responses. Recent studies have demonstrated that RLR activation induces antitumor immunity and cytotoxicity against different types of cancer, including lung cancer. However a previous report has demonstrated that ionizing radiation exerts a limited effect on RLR in human monocytic cell-derived macrophages, suggesting that RLR agonists may be used as effective immunostimulants during radiation therapy. However, it is unclear whether ionizing radiation affects the cytotoxicity of RLR agonists against cancer cells. Therefore, in the present study the effects of cotreatment with ionizing radiation and RLR agonists on cytotoxicity against human non-small cell lung cancer cells A549 and H1299 was investigated. Treatment with RLR agonist poly(I:C)/LyoVec™ [poly(I:C)] exerted cytotoxic effects against human non-small cell lung cancer. The cytotoxic effects of poly(I:C) were enhanced by cotreatment with ionizing radiation, and poly(I:C) pretreatment resulted in the radiosensitization of non-small cell lung cancer. Furthermore, cotreatment of A549 and H1299 cells with poly(I:C) and ionizing radiation effectively induced apoptosis in a caspase-dependent manner compared with treatment with poly(I:C) or ionizing radiation alone. These results indicate that RLR agonists and ionizing radiation cotreatment effectively exert cytotoxic effects against human non-small cell lung cancer through caspase-mediated apoptosis. PMID:29541243

Antibacterial Synthetic Peptides Derived from Bovine Lactoferricin Exhibit Cytotoxic Effect against MDA-MB-468 and MDA-MB-231 Breast Cancer Cell Lines.

PubMed

Vargas Casanova, Yerly; Rodríguez Guerra, Jorge Antonio; Umaña Pérez, Yadi Adriana; Leal Castro, Aura Lucía; Almanzar Reina, Giovanni; García Castañeda, Javier Eduardo; Rivera Monroy, Zuly Jenny

2017-09-29

Linear, dimeric, tetrameric, and cyclic peptides derived from lactoferricin B, containing the RRWQWR motif, were designed, synthesized, purified, and characterized using RP-HPLC chromatography and MALDI-TOF mass spectrometry. The antibacterial activity of the designed peptides against E. coli (ATCC 11775 and 25922) and their cytotoxic effect against MDA-MB-468 and MDA-MB-231 breast cancer cell lines were evaluated. Dimeric and tetrameric peptides showed higher antibacterial activity in both bacteria strains than linear peptides. The dimeric peptide (RRWQWR)₂K-Ahx exhibited the highest antibacterial activity against the tested bacterial strains. Furthermore, the peptides with high antibacterial activity exhibited significant cytotoxic effect against the tested breast cancer cell lines. This cytotoxic effect was fast and dependent on the peptide concentration. The tetrameric molecule containing RRWQWR motif has an optimal cytotoxic effect at a concentration of 22 µM. The evaluated dimeric and tetrameric peptides could be considered as candidates for developing new therapeutic agents against breast cancer. Polyvalence of linear sequences could be considered as a novel and versatile strategy for obtaining molecules with high anticancer activity.

Evaluation of the cytotoxicity of dihydroxytryptamines and 5-hydroxytryptamine antagonists as cytotoxic agents in dimethylhydrazine-induced adenocarcinomata.

PubMed

Tutton, P J; Barkla, D H

1978-01-01

The cytotoxicity of 5,6-dihydroxytryptamine (5,6-DHT), 5,7-dihydroxytryptamine (5,7-DHT), bromolysergic acid diethylamide (BOL), methysergide, and cyproheptadine, and also of 5,6-DHT together with either BOL, methysergide, or cyproheptadine in dimethylhydrazine-induced (DMH) carcinomata of rat colon was evaluated by estimating the percentage of necrotic cells in histological sections of tissues taken 15 h after injection of each of the drugs. In addition, the influence of methysergide and cyproheptadine on the tumour cell mitotic rate was estimated by means of a stathmokinetic technique. Both 5,6-DHT and 5,7-DHT were cytotoxic at each dose tested and for each of these agents the percentage of necrotic cells was directly correlated with the dose of drug used. BOL was not found to be cytotoxic to the colonic carcinomata, whereas both methysergide and cyproheptadine did cause detectable tumour cell necrosis. Methysergide was also found to accelerate tumour cell proliferation, whereas cyproheptadine did not. BOL competitively inhibited the cytotoxicity of 5,6-DHT and neither methysergide nor cyproheptadine potentiated the effect of 5,6 DHT.

Evaluation of the mutagenic and cytotoxic effects of mercurous chloride by the micronuclei technique in golden Syrian hamsters.

PubMed

Cortés-Gutiérrez, Elva I; Cerda-Flores, Ricardo M; González-Ramírez, Diego; Zúñiga-Charles, Miguel A; Lazcano-Martínez, Sigifredo; Sampayo-Reyes, Adriana; Leal-Garza, Carlos H

2004-05-01

The aims of this study were to evaluate the mutagenic and cytotoxic activity of mercurous chloride by the micronucleus technique in vivo on the bone marrow of golden Syrian hamsters after a single i.p. drug administration. Forty male golden Syrian hamsters were classified into eight groups: negative control, positive control and six groups treated with different doses of mercurous chloride (1.25, 2.5, 5, 10, 20 and 40 mg/kg). The negative control was injected with physiological saline i.p. and the positive control with cyclophosphamide at a dose of 80 mg/kg i.p. With respect to mutagenic effect, the average number of micronucleated polychromatic erythrocytes (MPE) in hamsters treated with different doses of mercurous chloride was not significant compared with the negative control. With respect to cytotoxic effect, the average polychromatic erythrocyte/red blood cell ratio showed a significant decrease when the doses were higher than the 2.5 mg/kg dose compared with the negative control. In conclusion, this preliminary study shows a cytotoxic effect but not a mutagenic effect of calomel in vivo at one time point (24 h).

Evaluation of protective and therapeutic effects of dexpanthenol on nasal decongestants and preservatives: results of cytotoxic studies in vitro.

PubMed

Klöcker, Norbert; Rudolph, Peter; Verse, Thomas

2004-01-01

More than 600 million units of nasal decongestants are sold worldwide annually. The cytotoxic and ciliary toxic potential of decongestants, as well as the preservatives of these products, in particular benzalkonium chloride (BKC), is well established. Recently, a beneficial effect of dexpanthenol on the tolerability of the alpha-sympathomimetic xylometazoline and BKC has been described; however, it was unclear if this effect, resulting in significantly higher cell counts in a cytotoxicity study and an increase in ciliary beat frequency in a ciliary toxicity study was of protective or therapeutic nature. The objective of this study was (a) to evaluate whether dexpanthenol would be a useful additive to nasal decongestants to counter the cytotoxic and ciliary toxic effects of the active ingredient and the preservative and (b) to find out whether this beneficial effect is of protective or therapeutic nature. Systematic cytotoxic in vitro tests were performed. After exposure to xylometazoline (0.1%), the effect of dexpanthenol (5%) and BKC (0.01%) was determined by placebo-controlled assessment of cell growth in a human amniotic cell line. Dexpanthenol significantly reduces the toxic effects of xylometazoline regarding cell growth (p < 0.001) when applied in advance. When BKC is eliminated from the nasal sprays, a further significant increase of cell growth was found (p < 0.001). When dexpanthenol is therapeutically applied after xylometazoline, effects on cell growth are only one-half of those of the protective approach. The additive application of dexpanthenol (5%) given before nasal decongestants or preserved nasal sprays is able to improve the tolerability of these substances and to counteract the toxic effects.

Cytological and ultrastructural studies on root tissues

NASA Technical Reports Server (NTRS)

Slocum, R. D.; Gaynor, J. J.; Galston, A. W.

1984-01-01

The anatomy and fine structure of roots from oat and mung bean seedlings, grown under microgravity conditions for 8 days aboard the Space Shuttle, was examined and compared to that of roots from ground control plants grown under similar conditions. Roots from both sets of oat seedlings exhibited characteristic monocotyledonous tissue organization and normal ultrastructural features, except for cortex cell mitochondria, which exhibited a 'swollen' morphology. Various stages of cell division were observed in the meristematic tissues of oat roots. Ground control and flight-grown mung bean roots also showed normal tissue organization, but root cap cells in the flight-grown roots were collapsed and degraded in appearance, especially at the cap periphery. At the ultrastructural level, these cells exhibited a loss of organelle integrity and a highly-condensed cytoplasm. This latter observation perhaps suggests a differing tissue sensitivity for the two species to growth conditions employed in space flight. The basis for abnormal root cap cell development is not understood, but the loss of these putative gravity-sensing cells holds potential significance for long term plant growth orientation during space flight.

Techniques to assess bone ultrastructure organization: orientation and arrangement of mineralized collagen fibrils

PubMed Central

Georgiadis, Marios; Müller, Ralph; Schneider, Philipp

2016-01-01

Bone's remarkable mechanical properties are a result of its hierarchical structure. The mineralized collagen fibrils, made up of collagen fibrils and crystal platelets, are bone's building blocks at an ultrastructural level. The organization of bone's ultrastructure with respect to the orientation and arrangement of mineralized collagen fibrils has been the matter of numerous studies based on a variety of imaging techniques in the past decades. These techniques either exploit physical principles, such as polarization, diffraction or scattering to examine bone ultrastructure orientation and arrangement, or directly image the fibrils at the sub-micrometre scale. They make use of diverse probes such as visible light, X-rays and electrons at different scales, from centimetres down to nanometres. They allow imaging of bone sections or surfaces in two dimensions or investigating bone tissue truly in three dimensions, in vivo or ex vivo, and sometimes in combination with in situ mechanical experiments. The purpose of this review is to summarize and discuss this broad range of imaging techniques and the different modalities of their use, in order to discuss their advantages and limitations for the assessment of bone ultrastructure organization with respect to the orientation and arrangement of mineralized collagen fibrils. PMID:27335222

Correlation between luminescence intensity and cytotoxicity in cell-based cytotoxicity assay using luciferase.

PubMed

Wakuri, S; Yamakage, K; Kazuki, Y; Kazuki, K; Oshimura, M; Aburatani, S; Yasunaga, M; Nakajima, Y

2017-04-01

The luciferase reporter assay has become one of the conventional methods for cytotoxicity evaluation. Typically, the decrease of luminescence expressed by a constitutive promoter is used as an index of cytotoxicity. However, to our knowledge, there have been no reports of the correlation between cytotoxicity and luminescence intensity. In this study, to accurately verify the correlation between them, beetle luciferase was stably expressed in human hepatoma HepG2 cells harboring the multi-integrase mouse artificial chromosome vector. We showed that the cytotoxicity assay using luciferase does not depend on the stability of luciferase protein and the kind of constitutive promoter. Next, HepG2 cells in which green-emitting beetle luciferase was expressed under the control of CAG promoter were exposed to 58 compounds. The luminescence intensity and cytotoxicity curves of cells exposed to 48 compounds showed similar tendencies, whereas those of cells exposed to 10 compounds did not do so, although the curves gradually approached each other with increasing exposure time. Finally, we demonstrated that luciferase expressed under the control of a constitutive promoter can be utilized both as an internal control reporter for normalizing a test reporter and for monitoring cytotoxicity when two kinds of luciferases are simultaneously used in the cytotoxicity assay. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparative effects between electronic and cigarette smoke in human keratinocytes and epithelial lung cells.

PubMed

Cervellati, F; Muresan, X M; Sticozzi, C; Gambari, R; Montagner, G; Forman, H J; Torricelli, C; Maioli, E; Valacchi, G

2014-08-01

Information about the harmful effects of vaping is sparse and inconsistent, therefore, since the use of electronic cigarettes (e-CIGs) has become increasingly popular as a tool to limit tobacco smoking, it is urgent to establish the toxicity of the commercial e-CIGs. Skin (HaCaT) and lung (A549) cells, the main targets of cigarette smoke (CS), were exposed to e-CIG vapor and CS using an in vitro system. The cytotoxic effect of the exposure was analyzed in both cell types by ultrastructural morphology, Trypan Blue exclusion test and LDH assay. In addition, pro-inflammatory cytokines were measured by the Bio-Plex assay. The cytotoxic components of e-CIG were restrained to the flavoring compound and, to a lesser extent, to nicotine although their effects were less harmful to that of CS. Humectants alone exhibited no cytotoxicity but induced the release of cytokines and pro-inflammatory mediators. Based on our results, we can state that exposure to e-CIG vapors results in far less toxic than exposure to CS. In fact, besides the deleterious effect of flavor and nicotine, even the humectants alone are able to evocate cytokines release. This study will hopefully promote the development of safer e-CIGs to help people quit smoking. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ultrastructural identification of peripheral myelin proteins by a pre-embedding immunogold labeling method.

PubMed

Canron, Marie-Hélène; Bouillot, Sandrine; Favereaux, Alexandre; Petry, Klaus G; Vital, Anne

2003-03-01

Ultrastructural immunolabeling of peripheral nervous system components is an important tool to study the relation between structure and function. Owing to the scarcity of certain antigens and the dense structure of the peripheral nerve, a pre-embedding technique is likely appropriate. After several investigations on procedures for pre-embedding immunolabeling, we propose a method that offers a good compromise between detection of antigenic sites and preservation of morphology at the ultrastructural level, and that is easy to use and suitable for investigations on peripheral nerve biopsies from humans. Pre-fixation by immersion in paraformaldehyde/glutaraldehyde is necessary to stabilize the ultrastructure. Then, ultrasmall gold particles with silver enhancement are advised. Antibodies against myelin protein zero and myelin basic protein were chosen for demonstration. The same technique was applied to localize a 35 kDa myelin protein.

Water pollution causes ultrastructural and functional damages in Pellia neesiana (Gottsche) Limpr.

PubMed

Basile, Adriana; Sorbo, Sergio; Lentini, Marco; Conte, Barbara; Esposito, Sergio

2017-09-01

The aim of this work is to evaluate the effects of freshwater pollution in the heavily contaminated Sarno River (Campania, South Italy), using Pellia neesiana (Pelliaceae Metzgeriales) in order to propose this liverwort as a potential bioindicator, able to record the effects of water pollution, particularly the one related to metal (loid) contamination. Samples of P. neesiana in nylon bags were disposed floating for one week on the waters of Sarno River in three sites characterised by an increasing pollution. As control, some specimens were cultured in vitro in Cd- and Pb-added media, at the same pollutants' levels as measured in the most polluted site. P. neesiana cell ultrastructure was modified and severe alterations were observed in chloroplasts from samples exposed in the most polluted site, and Cd- and Pb-cultured samples. Concurrently, a strong increase in the occurrence of Heat shock proteins 70 (HSP70) was detected in gametophytes following the pollution gradient. In conclusion, ultrastructural damages can be directly related to HSP 70 occurrence in liverwort tissues, and proportional to the degree of pollution present in the river; thus our study suggests P. neesiana as an affordable bioindicator of freshwaters pollution. Copyright © 2016 Elsevier GmbH. All rights reserved.

Down-Regulation of Glucose-Regulated Protein (GRP) 78 Potentiates Cytotoxic Effect of Celecoxib in Human Urothelial Carcinoma Cells

PubMed Central

Huang, Kuo-How; Kuo, Kuan-Lin; Chen, Shyh-Chyan; Weng, Te-I; Chuang, Yuan-Ting; Tsai, Yu-Chieh; Pu, Yeong-Shiau; Chiang, Chih-Kang; Liu, Shing-Hwa

2012-01-01

Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor that has been reported to elicit anti-proliferative response in various tumors. In this study, we aim to investigate the antitumor effect of celecoxib on urothelial carcinoma (UC) cells and the role endoplasmic reticulum (ER) stress plays in celecoxib-induced cytotoxicity. The cytotoxic effects were measured by MTT assay and flow cytometry. The cell cycle progression and ER stress-associated molecules were examined by Western blot and flow cytometry. Moreover, the cytotoxic effects of celecoxib combined with glucose-regulated protein (GRP) 78 knockdown (siRNA), (−)-epigallocatechin gallate (EGCG) or MG132 were assessed. We demonstrated that celecoxib markedly reduces the cell viability and causes apoptosis in human UC cells through cell cycle G1 arrest. Celecoxib possessed the ability to activate ER stress-related chaperones (IRE-1α and GRP78), caspase-4, and CCAAT/enhancer binding protein homologous protein (CHOP), which were involved in UC cell apoptosis. Down-regulation of GRP78 by siRNA, co-treatment with EGCG (a GRP78 inhibitor) or with MG132 (a proteasome inhibitor) could enhance celecoxib-induced apoptosis. We concluded that celecoxib induces cell cycle G1 arrest, ER stress, and eventually apoptosis in human UC cells. The down-regulation of ER chaperone GRP78 by siRNA, EGCG, or proteosome inhibitor potentiated the cytotoxicity of celecoxib in UC cells. These findings provide a new treatment strategy against UC. PMID:22438966

Hematology, cytochemistry and ultrastructure of blood cells in fishing cat (Felis viverrina)

PubMed Central

Salakij, Chaleow; Apibal, Suntaree; Narkkong, Nual-Anong

2007-01-01

Hematological, cytochemical and ultrastructural features of blood cells in fishing cat (Felis viverrina) were evaluated using complete blood cell counts with routine and cytochemical blood stains, and scanning and transmission electron microscopy. No statistically significant difference was found in different genders of this animal. Unique features of blood cells in this animal were identified in hematological, cytochemical and ultrastructural studies. This study contributes to broaden hematological resources in wildlife animals and provides a guideline for identification of blood cells in the fishing cat. PMID:17519570

[Adverse muscle effects of a podofyllotoxin-containing cytotoxic drug product with simvastatin].

PubMed

Kaipiainen-Seppänen, Oili; Savolainen, Elina; Elfving, Pia; Kononoff, Aulikki

2009-01-01

With the ageing population, drug interactions pose an increasing challenge to health professionals. We describe four patients, for whom concurrent administration of a podofyllotoxin-containing cytotoxic drug product and simvastatin caused severe adverse effects on muscles, including muscle pain, soreness or fatigue or weakness, and in some patients also disintegration of muscle tissue, i.e. rhabdomyolysis. The metabolism of both drugs proceeds via the common CYP3A4 enzyme pathway.

Uremic toxins enhance statin-induced cytotoxicity in differentiated human rhabdomyosarcoma cells.

PubMed

Uchiyama, Hitoshi; Tsujimoto, Masayuki; Shinmoto, Tadakazu; Ogino, Hitomi; Oda, Tomoko; Yoshida, Takuya; Furukubo, Taku; Izumi, Satoshi; Yamakawa, Tomoyuki; Tachiki, Hidehisa; Minegaki, Tetsuya; Nishiguchi, Kohshi

2014-09-03

The risk of myopathy and rhabdomyolysis is considerably increased in statin users with end-stage renal failure (ESRF). Uremic toxins, which accumulate in patients with ESRF, exert cytotoxic effects that are mediated by various mechanisms. Therefore, accumulation of uremic toxins might increase statin-induced cytotoxicity. The purpose of this study was to determine the effect of four uremic toxins-hippuric acid, 3-carboxy-4-methyl-5-propyl-2-furanpropionate, indole-3-acetic acid, and 3-indoxyl sulfate-on statin-induced myopathy. Differentiated rhabdomyosarcoma cells were pre-treated with the uremic toxins for seven days, and then the cells were treated with pravastatin or simvastatin. Cell viability and apoptosis were assessed by viability assays and flow cytometry. Pre-treatment with uremic toxins increased statin- but not cisplatin-induced cytotoxicity (p < 0.05 vs. untreated). In addition, the pre-treatment increased statin-induced apoptosis, which is one of the cytotoxic factors (p < 0.05 vs. untreated). However, mevalonate, farnesol, and geranylgeraniol reversed the effects of uremic toxins and lowered statin-induced cytotoxicity (p < 0.05 vs. untreated). These results demonstrate that uremic toxins enhance statin-induced apoptosis and cytotoxicity. The mechanism underlying this effect might be associated with small G-protein geranylgeranylation. In conclusion, the increased severity of statin-induced rhabdomyolysis in patients with ESRF is likely due to the accumulation of uremic toxins.

Cytotoxic effect of Alpinia scabra (Blume) Náves extracts on human breast and ovarian cancer cells

PubMed Central

2013-01-01

Background Alpinia scabra, locally known as 'Lengkuas raya’, is an aromatic, perennial and rhizomatous herb from the family Zingiberaceae. It is a wild species which grows largely on mountains at moderate elevations in Peninsular Malaysia, but it can also survive in the lowlands like in the states of Terengganu and Northern Johor. The present study reports the cytotoxic potential of A. scabra extracts from different parts of the plant. Methods The experimental approach in the present study was based on a bioassay-guided fractionation. The crude methanol and fractionated extracts (hexane, chloroform and water) from different parts of A. scabra (leaves, rhizomes, roots and pseudo stems) were prepared prior to the cytotoxicity evaluation against human ovarian (SKOV-3) and hormone-dependent breast (MCF7) carcinoma cells. The identified cytotoxic extracts were then subjected to chemical investigations in order to identify the active ingredients. A normal human lung fibroblast cell line (MRC-5) was used to determine the specificity for cancerous cells. The cytotoxic extracts and fractions were also subjected to morphological assessment, DNA fragmentation analysis and DAPI nuclear staining. Results The leaf (hexane and chloroform) and rhizome (chloroform) extracts showed high inhibitory effect against the tested cells. Ten fractions (LC1-LC10) were yielded after purification of the leaf chloroform extract. Fraction LC4 which showed excellent cytotoxic activity was further purified and resulted in 17 sub-fractions (VLC1-VLC17). Sub-fraction VLC9 showed excellent cytotoxicity against MCF7 and SKOV-3 cells but not toxic against normal MRC-5 cells. Meanwhile, eighteen fractions (RC1-RC18) were obtained after purification of the rhizome chloroform extract, of which fraction RC5 showed cytotoxicity against SKOV-3 cells with high selectivity index. There were marked morphological changes when observed using phase-contrast inverted microscope, DAPI nuclear staining and also DNA

Suppression of miR-19b enhanced the cytotoxic effects of mTOR inhibitors in human neuroblastoma cells.

PubMed

Chen, Yun; Tsai, Ya-Hui; Tseng, Bor-Jiun; Pan, Hsin-Yen; Tseng, Sheng-Hong

2016-11-01

Mammalian target of rapamycin (mTOR) inhibitors exert significant antitumor effects on several cancer cell types. In this study, we investigated the effects of mTOR inhibitors, in particular the regulation of the microRNA, in neuroblastoma cells. AZD8055 (a new mTOR inhibitor)- or rapamycin-induced cytotoxic effects on neuroblastoma cells were studied. Western blotting was used to investigate the expression of various proteins in the mTOR pathway. MicroRNA precursors and antagomirs were transfected into cells to manipulate the expression of target microRNA. AZD8055 exerted stronger cytotoxic effects than rapamycin in neuroblastoma cells (p<0.03). In addition, AZD8055 suppressed the mTOR pathway and increased the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in the neuroblastoma cells. AZD8055 significantly decreased miR-19b expression (p<0.005); in contrast, rapamycin increased miR-19b expression (p<0.05). Transfection of miR-19b antagomir into the neuroblastoma cells mimicked the effects of AZD8055 treatment, whereas miR-19b overexpression reversed the effects of AZD8055. Combination of miR-19b knockdown and rapamycin treatment significantly improved the sensitivity of neuroblastoma cells to rapamycin (p<0.02). Suppression of miR-19b may enhance the cytotoxic effects of mTOR inhibitors in neuroblastoma cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Cytotoxic activity of four Mexican medicinal plants.

PubMed

Vega-Avila, Elisa; Espejo-Serna, Adolfo; Alarcón-Aguilar, Francisco; Velasco-Lezama, Rodolfo

2009-01-01

Ibervillea sonorae Greene, Cucurbita ficifolia Bouché, Tagetes lucida Cav and Justicia spicigera Scheltdd are Mexican native plants used in the treatment of different illnesses. The ethanolic extract of J. spicigera and T. lucida as well as aqueous extracts from I. sonorae, C. ficifolia, T. lucida and J. spicigera were investigated using sulforhodamine B assay. These extracts were assessed using two cell line: T47D (Human Breast cancer) and HeLa (Human cervix cancer). Colchicine was used as the positive control. Data are presented as the dose that inhibited 50% control growth (ED50). All of the assessed extracts were cytotoxic (ED50 < 20 microg/ml) against T47D cell line, meanwhile only the aqueous extract from T. lucida and the ethanolic extract from J. spicigera were cytotoxic to HeLa cell line. Ethanolic extract from J. spicigera presented the best cytotoxic effect. The cytotoxic activity of J. spicigera correlated with one of the popular uses, the treatment of cancer.

Cytotoxicity of the rhizome of medicinal plants

PubMed Central

Hossain, Shakhawoat; Kader, Golam; Nikkon, Farjana; Yeasmin, Tanzima

2012-01-01

Objective To investigate the cytotoxicity of the crude ethanol extract of the rhizome of Zingiber zerumbet (Z. zerumbet) (L) Smith. and Curcuma zedoaria (C. zedoaria) Rosc. against Artemia salina Leach. Methods Fresh rhizomes of Z. zerumbet (L) Smith. and C. zedoaria Rosc. were extracted separately in cold with ethanol (2.5 L) and after concentration a brownish syrupy suspension of ethanol extracts of Z. zerumbet (L) Smith. and C. zedoaria Rosc. was obtained. The cytotoxic effect of the crude ethanol extracts of both plants was determined by brine shrimp lethality bioassay. Results Crude ethanol extracts of the rhizome of Z. zerumbet (L) Smith. showed the highest cytotoxicity (LC50 was 1.24 µg/mL) against brine shrimp nauplii as compared with C. zedoaria Rosc. (LC50 was 33.593 µg/mL) after 24 h of exposure. Conclusions It can be concluded that the rhizome of Z. zerumbet (L) Smith. and C. zedoaria Rosc. can be used as a source of cytotoxic agent. PMID:23569881

Chemical transformations on botryane skeleton. Effect on the cytotoxic activity.

PubMed

Reino, José L; Durán-Patrón, Rosa; Segura, Inmaculada; Hernández-Galán, Rosario; Riese, Hans H; Collado, Isidro G

2003-03-01

Eighteen compounds with a botryane skeleton have been obtained through chemical transformations of various toxins from the fungus Botrytis cinerea. During the course of these transformations, the C-10 carbon of the botryane skeleton was found to exhibit an interesting high regioselectivity to oxidizing and reducing agents. In addition, the cytotoxicity of 27 botryane derivatives was determined in vitro against Hs578T, MDA-MB-231, HT-1080, U87-MG, IMR-90, and HUVEC cell lines. The results of this study confirm that the cytotoxicity of botrydial (1) and its derivatives is related to the presence of a 1,5-dialdehyde functionality.

Effects of different surface modifying agents on the cytotoxic and antimicrobial properties of ZnO nanoparticles.

PubMed

Esparza-González, S C; Sánchez-Valdés, S; Ramírez-Barrón, S N; Loera-Arias, M J; Bernal, J; Meléndez-Ortiz, H Iván; Betancourt-Galindo, R

2016-12-01

Zinc oxide (ZnO) nanoparticles (NPs) have received considerable attention in the medical field because of their antibacterial properties, primarily for killing and reducing the activity of numerous microorganisms. The purpose of this study was to determine whether surface-modified ZnO NPs exhibit different properties compared with unmodified ZnO. The antimicrobial and cytotoxic properties of modified ZnO NPs as well as their effects on inflammatory cytokine production were evaluated. ZnO NPs were prepared using a wet chemical method. Then, the surfaces of these NPs were modified using 3-aminopropyltriethoxysilane (APTES) and dimethyl sulfoxide (DMSO) as modifying agents via a chemical hydrolysis method. According to infrared spectroscopy analysis (FTIR), the structure of the ZnO remained unchanged after modification. Antibacterial assays demonstrated that APTES modification is more effective at inducing an antimicrobial effect against Gram-negative bacteria than against Gram-positive bacteria. Cytotoxicity studies showed that cell viability was dose-dependent; moreover, pristine and APTES-modified ZnO exhibited low cytotoxicity, whereas DMSO-modified ZnO exhibited toxicity even at a low NP concentration. An investigation of inflammatory cytokine production demonstrated that the extent of stimulation was related to the ZnO NP concentration but not to the surface modification, except for IFN-γ and IL-10, which were not detected even at high NP concentrations. Copyright © 2016 Elsevier B.V. All rights reserved.

Cytotoxic effects of Pinus eldarica essential oil and extracts on HeLa and MCF-7 cell lines

PubMed Central

Sarvmeili, Najmeh; Jafarian-Dehkordi, Abbas; Zolfaghari, Behzad

2016-01-01

Several attempts have so far been made in the search of new anticancer agents of plant origin. Some studies have reported that different species of Pine genus possess cytotoxic activities against various cancer cell lines. In the present study, we evaluated the cytotoxic effects of Pinus eldarica bark and leaf extracts or leaf essential oil on HeLa and MCF-7 tumor cell lines. Hydroalcoholic and phenolic extracts and the essential oil of plant were prepared. Total phenolic contents of the extracts were measured using Folin-Ciocalteu reagent. Essential oil components were determined by gas chromatography-mass spectroscopy (GC-MS). Cytotoxic activity of the extracts and essential oil against HeLa and MCF-7 tumor cell lines were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The polyphenolic content of hydroalcoholic and phenolic extracts of the bark and hydroalcoholic extract of the leaf were 48.31%, 47.2%, and 8.47%, respectively. According to the GC-MS analysis, the major components of the leaf oil of P. eldarica were: β -caryophyllene (14.8%), germacrene D (12.9%), α–terpinenyl acetate (8.15%), α –pinene (5.7%), and –α humulene (5.9%). Bark extracts and leaf essential oil of P. eldarica significantly reduced the viability of both HeLa and MCF-7 cells in a concentration dependent manner. However, leaf extract showed less inhibitory effects against both cell lines. The essential oil of P. eldarica was more cytotoxic than its hydroalcoholic and phenolic extracts. The terpenes and phenolic compounds were probably responsible for cytotoxicity of P. eldarica. Therefore, P. eldarica might have a good potential for active anticancer agents. PMID:28003841

Antileishmanial activity and ultrastructural alterations of Leishmania (L.) chagasi treated with the calcium channel blocker nimodipine.

PubMed

Tempone, André Gustavo; Taniwaki, Noemi Nosomi; Reimão, Juliana Quero

2009-08-01

In a search for novel antileishmanial drugs, we investigated the activity of the calcium channel blocker nimodipine against Leishmania spp. and explored the ultrastructural damages of parasites induced by nimodipine after a short period of incubation. Nimodipine was highly effective against promastigotes and intracellular amastigotes of Leishmania (L.) chagasi, with 50% inhibitory concentration values of 81.2 and 21.5 muM, respectively. Nimodipine was about fourfold more effective than the standard pentavalent antimony against amastigotes and showed a Selectivity Index of 4.4 considering its mammalian cells toxicity. Leishmania (L.) amazonensis and Leishmania (L.) major promastigotes were also susceptible to nimodipine in a range concentration between 31 and 128 muM. Ultrastructural studies of L. (L.) chagasi revealed intense mitochondria damage and plasma membrane blebbing, resulting in a leishmanicidal effect as demonstrated by the lack of mitochondrial oxidative metabolism. The amastigote-killing effect suggests other mechanism than macrophage activation, as no upregulation of nitric oxide was seen. This calcium channel blocker is an effective in vitro antileishmanial compound and if adequately studied could be used as a novel drug candidate or as a novel drug lead compound for drug design studies against leishmaniasis.

Apigenin induced apoptosis in esophageal carcinoma cells by destruction membrane structures.

PubMed

Zhu, Haiyan; Jin, Hua; Pi, Jiang; Bai, Haihua; Yang, Fen; Wu, Chaomin; Jiang, Jinhuan; Cai, Jiye

2016-07-01

Apigenin has shown to have killing effects on some kinds of solid tumor cells. However, the changes in cell membrane induced by apigenin on subcellular- or nanometer-level were still unclear. In this work, human esophageal cancer cells (EC9706 and KYSE150 cells) were employed as cell model to detect the cytotoxicity of apigenin, including cell growth inhibition, apoptosis induction, membrane toxicity, etc. MTT assay showed that apigenin could remarkably inhibit the growth and proliferation in both types of cells. Annexin V/PI-based flow cytometry analysis showed that the cytotoxic effects of apigenin in KYSE150 cells were mainly through early apoptosis induction, while in EC9706 cells, necrosis, and apoptosis were both involved in cell death. The morphological and ultrastructural properties induced by apigenin were investigated at single cellular- or nanometer-level using atomic force microscopy (AFM). Additionally, lactate dehydrogenase (LDH) leakage was measured to assess the changes in membrane permeability. The results indicated that apigenin increased the membrane permeability and caused leakage of LDH, which was consistent with damages on membrane ultrastructure detected by AFM. Therefore, membrane toxicity, including membrane ultrastructure damages and enhanced membrane permeability, played vital roles in apigenin induced human esophageal cancer cell apoptosis. SCANNING 38:322-328, 2016. © 2015 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

The effects of levofloxacin on rabbit fibroblast-like synoviocytes in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Yang; Lu, Kaihang; Deng, Yu

2012-12-01

It is widely accepted that tendon and cartilage are adversely affected with the toxic effects of quinolones. However, the effects of quinolones on synovium have not been deciphered completely. In this study, our main objective was to investigate the effects of levofloxacin, a typical quinolone antibiotic drug, on fibroblast-like synoviocytes (FLSs) in vitro. FLSs of rabbits were treated with levofloxacin at different concentrations (0, 14, 28, 56, 112 and 224 μM). The possible cytotoxic effects of levofloxacin on FLS were determined. Levofloxacin significantly reduced the cell viabilities, gene expression of hyaluronan synthase-2 (HAS-2), and the level of hyaluronan in FLSs.more » Moreover, levofloxacin-induced concentration-dependent increases of apoptosis and active caspase-3 were determined in this study. Ultrastructural damages of FLSs were observed by electron microscopy. The mRNA expression levels of matrix metalloproteinase (MMP)-3 and MMP-13 were increased in FLSs treated with levofloxacin. In addition, levofloxacin played a role in suppressing the expression of interleukin (IL)-1 and IL-6. Our data suggest that the cytotoxic effects of levofloxacin on FLS were shown to be able to affect cell viability and HA synthesis capacity. The potential mechanisms of the cytotoxic effects may be attributed to the apoptosis and increased expression of MMPs. -- Highlights: ► Levofloxacin decreases hyaluronic acid synthesis in fibroblast-like synoviocytes. ► Levofloxacin exerts pro-apoptosis effects on fibroblast-like synoviocytes. ► Levofloxacin increases gene expression of MMPs in fibroblast-like synoviocytes. ► Levofloxacin exerts anti-inflammatory effects on fibroblast-like synoviocytes.« less

Insight into Bone-Derived Biological Apatite: Ultrastructure and Effect of Thermal Treatment

PubMed Central

Liu, Quan; Pan, Haobo; Chen, Zhuofan; Matinlinna, Jukka Pekka

2015-01-01

Objectives. This study aims at examining the ultrastructure of bone-derived biological apatite (BAp) from a series of small vertebrates and the effect of thermal treatment on its physiochemical properties. Materials and Methods. Femurs/fin rays and vertebral bodies of 5 kinds of small vertebrates were firstly analyzed with X-ray microtomography. Subsequently, BAp was obtained with thermal treatment and low power plasma ashing, respectively. The properties of BAp, including morphology, functional groups, and crystal characteristics were then analyzed. Results. The bones of grouper and hairtail were mainly composed of condensed bone. Spongy bone showed different distribution in the bones from frog, rat, and pigeon. No significant difference was found in bone mineral density of condensed bone and trabecular thickness of spongy bone. Only platelet-like crystals were observed for BAp obtained by plasma ashing, while rod-like and irregular crystals were both harvested from the bones treated by sintering. A much higher degree of crystallinity and larger crystal size but a lower content of carbonate were detected in the latter. Conclusion. Platelet-like BAp is the common inorganic component of vertebrate bones. BAp distributing in condensed and spongy bone may exhibit differing thermal reactivity. Thermal treatment may alter BAp's in vivo structure and composition. PMID:25695088

Cytotoxic effect of galvanically coupled magnesium-titanium particles.

PubMed

Kim, Jua; Gilbert, Jeremy L

2016-01-01

Recent work has shown that reduction reactions at metallic biomaterial surfaces can induce significant killing of cells in proximity to the surface. To exploit this phenomenon for therapeutic purposes, for example, for cancer tumor killing or antibacterial effects (amongst other applications), magnesium metal particles, galvanically coupled to titanium by sputtering, have been evaluated for their cell-killing capability (i.e. cytotoxicity). Magnesium (Mg) particles large enough to prevent particle phagocytosis were investigated, so that only electrochemical reactions, and not particle toxicity per se, caused cytotoxic effects. Titanium (Ti) coated magnesium particles, as well as magnesium-only particles were introduced into MC3T3-E1 mouse pre-osteoblast cell cultures over a range of particle concentrations, and cells were observed to die in a dosage-dependent manner. Ti-coated magnesium particles killed more cells at lower particle concentration than magnesium alone (P<0.05), although the pH measured for magnesium and magnesium-titanium had no significant difference at similar particle concentrations. Complete cell killing occurred at 750μg/ml and 1500μg/ml for Mg-Ti and Mg, respectively. Thus, this work demonstrates that galvanically coupled Mg-Ti particles have a significant cell killing capability greater than Mg alone. In addition, when the pH associated with complete killing with particles was created using NaOH only (no particles), then the percentage of cells killed was significantly less (P<0.05). Together, these findings show that pH is not the sole factor associated with cell killing and that the electrochemical reactions, including the reduction reactions, play an important role. Reduction reactions on galvanically coupled Mg-Ti and Mg particles may generate reactive oxygen intermediates that are able to kill cells in close proximity to the particles and this approach may lead to potential therapies for infection and cancer. This paper demonstrates

Localized Irradiation of Cell Membrane by Auger Electrons Is Cytotoxic Through Oxidative Stress-Mediated Nontargeted Effects

PubMed Central

Paillas, Salomé; Ladjohounlou, Riad; Lozza, Catherine; Pichard, Alexandre; Boudousq, Vincent; Jarlier, Marta; Sevestre, Samuel; Le Blay, Marion; Deshayes, Emmanuel; Sosabowski, Jane; Chardès, Thierry; Navarro-Teulon, Isabelle; Mairs, Robert J.

2016-01-01

Abstract Aims: We investigated whether radiation-induced nontargeted effects are involved in the cytotoxic effects of anticell surface monoclonal antibodies labeled with Auger electron emitters, such as iodine 125 (monoclonal antibodies labeled with 125I [125I-mAbs]). Results: We showed that the cytotoxicity of 125I-mAbs targeting the cell membrane of p53+/+ HCT116 colon cancer cells is mainly due to nontargeted effects. Targeted and nontargeted cytotoxicities were inhibited in vitro following lipid raft disruption with Methyl-β-cyclodextrin (MBCD) or filipin or use of radical oxygen species scavengers. 125I-mAb efficacy was associated with acid sphingomyelinase activation and modulated through activation of the AKT, extracellular signal-related kinase ½ (ERK1/2), p38 kinase, c-Jun N-terminal kinase (JNK) signaling pathways, and also of phospholipase C-γ (PLC-γ), proline-rich tyrosine kinase 2 (PYK-2), and paxillin, involved in Ca2+ fluxes. Moreover, the nontargeted response induced by directing 5-[(125)I]iodo-2′-deoxyuridine to the nucleus was comparable to that of 125I-mAb against cell surface receptors. In vivo, we found that the statistical significance of tumor growth delay induced by 125I-mAb was removed after MBCD treatment and observed oxidative DNA damage beyond the expected Auger electron range. These results suggest the involvement of nontargeted effects in vivo also. Innovation: Low-energy Auger electrons, such as those emitted by 125I, have a short tissue range and are usually targeted to the nucleus to maximize their cytotoxicity. In this study, we show that targeting the cancer cell surface with 125I-mAbs produces a lipid raft-mediated nontargeted response that compensates for the inferior efficacy of non-nuclear targeting. Conclusion: Our findings describe the mechanisms involved in the efficacy of 125I-mAbs targeting the cancer cell surface. Antioxid. Redox Signal. 25, 467–484. PMID:27224059

The cytotoxic effect of Elephantopus scaber Linn extract against breast cancer (T47D) cells

NASA Astrophysics Data System (ADS)

Sulistyani, N.; Nurkhasanah

2017-11-01

Breast cancer is one of the main cause of death. Elephantopus scaber Linn (ES) which has been used as a traditional medicine contains an antitumor compounds. This study aimed to explore the active fraction from ethanolic extract of ES as anticancer and to determine its inhibition effect on the cell proliferation cycle of breast cancer (T47D) cells. The ES leaf was macerated with ethanol and then evaporated to get the concentrated extract. The extract was fractionated using petroleum ether, chloroform, and methanol respectively. The cytotoxic activity of each fraction was carried out with MTT method, and the inhibition of cell cycle test were observed by flowcytometry method. The result showed that ES and the fractions have cytotoxic activity against T47D cell lines with IC50 values of extract, petroleum ether, chloroform, and methanol fractions were 58.36±2.38, 132.17±9.69, 7.08±2.11, and 572.89±69.23 µg/mL. The inhibition effect of ethanol extract on the lifecycle of cells was occured in sub G1 phase. There was no prolonging of G1, S, G2/M and polyploidy phase of T47D cell lines. The chloroform fraction of ES is the most cytotoxic fraction against T47D cells without prolonging the cell lifecycle.

Effect of artificial saliva with different pH levels on the cytotoxicity of soft denture lining materials.

PubMed

Akay, Canan; Tanış, Merve Ç; Sevim, Handan

2017-10-13

The aim of this study was to evaluate the cytotoxic effects of 9 different soft denture liners on the viability of L-929 mouse fibroblast cells at different incubation periods by storing them in artificial saliva (AS) with different pH levels. 96 disk samples from each lining material were prepared and divided into 4 groups: GI: No treatment; GII: Stored in artificial saliva with pH 3 for 21 days; Group III: Stored in artificial saliva with pH 7 for 21 days; and Group IV: Stored in artificial saliva with pH 14 for 21 days. The cytotoxicity of the extracts to cultured mouse fibroblasts (L-929) was measured by MTT (tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-dipHnyltetrazolium bromide) assay. Data were analyzed using 1-way analysis of variation (ANOVA). It was found that for the pH 3 values of New Truliner, Trusoft, Mollosil Plus, Dentusil, TDV, and HydroCast®; for the pH 7 values of Ufi Gel P and Elite plus; and for the pH 14 values of HydroCast®, there was a noncytotoxic effect during both the 24-hour and 48-hour incubation periods. In the control group 48-hour incubation period, HydroCast®, TDV, Mollosil, 24-hour incubation period Elite plus, for pH 3 values; Elite Plus 24-hour incubation period, for pH 7 values Trusoft 48-hour incubation period there was a moderately cytotoxic effect. This in vitro study revealed that storage in artificial saliva with different pH levels can affect the cytotoxicity of soft lining materials.

Combined and independent cytotoxicity of sodium hypochlorite, ethylenediaminetetraacetic acid and chlorhexidine.

PubMed

Vouzara, T; Koulaouzidou, E; Ziouti, F; Economides, N

2016-08-01

To evaluate the capacity of commonly used root canal irrigants to induce cytotoxic effects, when applied singly or in combination. The hypothesis tested was that the irrigants were less cytotoxic when applied in combination than independently. MRC5 cells were grown as monolayer cultures at 37 °C in an atmosphere containing 5% CO2 in air and 100% relative humidity. Cells were exposed to sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), chlorhexidine (CHX) and their combinations (NaOCl/EDTA, NaOCl/CHX, EDTA/CHX) in serial dilutions. Growth medium was Dulbecco's modified Eagle's medium supplemented with 10% foetal bovine serum and antibiotics and was used as control. The effect on cell survival was estimated after 6 and 24 h of exposure by means of the sulforhodamine B assay, in reference to controls. Dose-response curves were plotted, and 50% inhibitory doses (IC50 ) were subjected to statistical analysis (anova and post hoc comparison test; P < 0.05). Analysis of cell survival and interaction of the irrigants was performed using CalcuSyn dose effect analyzer software to calculate a combination index (CI). The tested irrigants were cytotoxic in dose- and time-dependent manner. CHX was the most cytotoxic irrigant tested, followed by NaOCl, whilst EDTA was the least cytotoxic irrigant tested. The difference between CHX and NaOCl was significant (P < 0.05) as well as between NaOCl and EDTA (P < 0.05). Based on CalcuSyn modelling, a mainly antagonistic effect was recorded with NaOCl/CHX and NaOCl/EDTA combinations. The combination EDTA/CHX had an additive to antagonistic effect. CHX was significantly more cytotoxic than NaOCl and EDTA. NaOCl was significantly more cytotoxic than EDTA. The combined action of irrigants did not produce a significant increase in their cytotoxicity. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Newer cytotoxic agents: attacking cancer broadly.

PubMed

Teicher, Beverly A

2008-03-15

The plasticity and instability of the cancer genome is impressive and is characterized by gene amplifications and deletions, rearrangements, and many silent and active mutations. Although targeted therapeutics have had effect in some diseases, there remains a large role for new cytotoxic agents that have the potential to be broadly active across multiple cancers. Platinum-based regimens are the basis for treatment of several common tumors. Satraplatin and picoplatin are newer platinum complexes that form bulkier lesions in DNA than their forerunners. Microtubules are a key target for anticancer agents. Vinca alkaloid and similar compounds fragment these critical structures, whereas taxanes stabilize them. Vinflunine is a new fluorinated Vinca alkaloid derivative with vascular disrupting effects, as well as antitumor effects. Epothilones are a new class of microtubule stabilizers. Mitosis has been targeted directly and indirectly by many anticancer agents. The aurora kinases are new targets in this class. Inhibitors of aurora kinases are likely to be cytotoxic. Finally, protein regulation is essential for cellular integrity. With the approval of bortezomib (Velcade, PS-341), the proteosome, a master protein regulator, has been validated as an anticancer target. The five articles in this issue of CCR Focus present the current status of these next generation cytotoxic agents.

Effect of heat shock on ultrastructure and calcium distribution in Lavandula pinnata L. glandular trichomes.

PubMed

Huang, S S; Kirchoff, B K; Liao, J P

2013-02-01

The effects of heat shock (HS) on the ultrastructure and calcium distribution of Lavandula pinnata secretory trichomes are examined using transmission electron microscopy and potassium antimonate precipitation. After 48-h HS at 40°C, plastids become distorted and lack stroma and osmiophilic deposits, the cristae of the mitochondria become indistinct, the endoplasmic reticulum acquires a chain-like appearance with ribosomes prominently attached to the lamellae, and the plasma and organelle membranes become distorted. Heat shock is associated with a decrease in calcium precipitates in the trichomes, while the number of precipitates increases in the mesophyll cells. Prolonged exposure to elevated calcium levels may be toxic to the mesophyll cells, while the lack of calcium in the glands cell may deprive them of the normal protective advantages of elevated calcium levels. The inequality in calcium distribution may result not only from uptake from the transpiration stream, but also from redistribution of calcium from the trichomes to the mesophyll cells.

Time-resolved Ultrastructural Detection of Phosphatidylinositol 3-phosphate

PubMed Central

Stuffers, Susanne; Malerød, Lene; Schink, Kay Oliver; Corvera, Silvia; Stenmark, Harald; Brech, Andreas

2010-01-01

Phosphatidylinositol 3-phosphate [PtdIns(3)P] plays an important role in recruitment of various effector proteins in the endocytic and autophagic pathways. In an attempt to follow the distribution of PtdIns(3)P at the ultrastructural level, we are using the Fab1, YOTB, Vac1, and EEA1 (FYVE) domain, which is a zinc finger motif specifically binding to PtdIns(3)P. To follow PtdIns(3)P trafficking during a defined time window, here we have used a monomeric dimerizable FYVE probe, which binds with high avidity to PtdIns(3)P only after rapalog-induced dimerization. The probe localized to early and late endocytic compartments according to the time period of dimerization, which indicates that PtdIns(3)P is turned over via the endocytic machinery. In the functional context of epidermal growth factor (EGF) stimulation, we observed that dimerization of the probe led to clustering of mainly early endocytic structures, leaving most of the probe localized to the limiting membrane of endosomes. Interestingly, these clustered endosomes contained coats positive for the PtdIns(3)P-binding protein hepatocyte growth factor–regulated tyrosine kinase substrate (Hrs), indicating that the probe did not displace Hrs binding. We conclude that the dimerizer-inducible probe is useful for the time-resolved detection of PtdIns(3)P at the ultrastructural level, but its effects on endosome morphology after EGF stimulation need to be taken into account. (J Histochem Cytochem 58:1025–1032, 2010) PMID:20713985

Subacute ghrelin administration inhibits apoptosis and improves ultrastructural abnormalities in remote myocardium post-myocardial infarction.

PubMed

Eid, Refaat A; Zaki, Mohamed Samir Ahmed; Al-Shraim, Mubarak; Eleawa, Samy M; El-Kott, Attalla Farag; Al-Hashem, Fahaid H; Eldeen, Muhammad Alaa; Ibrahim, Hoja; Aldera, Hussain; Alkhateeb, Mahmoud A

2018-05-01

This study investigated the effect of ghrelin on cardiomyocytes function, apoptosis and ultra-structural alterations of remote myocardium of the left ventricle (LV) of rats, 21 days post myocardial infarction (MI). Rats were divided into 4 groups as a control, a sham-operated rats, a sham-operated+ghrelin, an MI + vehicle and an MI + ghrelin-treated rats. MI was induced by LAD ligation and then rats were recievd a concomitant doe of either normal saline as a vehicle or treated with ghrelin (100 μg/kg S.C., 2x/day) for 21 consecutive days. Ghrelin enhanced myocardial contractility in control rats and reversed the decreases in myocardial contractility and the increases in the serum levels of CK-MB and LDH in MI-induced rats. Additionally, it inhibited the increases in levels of Bax and cleaved caspase 3 and increased those for Bcl-2 in the remote myocardium of rat's LV, post-MI. At ultra-structural level, while ghrelin has no adverse effects on LV myocardium obtained from control or sham-treated rats, ghrelin post-administration to MI-induced rats reduced vascular formation, restored normal microfilaments appearance and organization, preserved mitochondria structure, and prevented mitochondrial swelling, collagen deposition and number of ghost bodies in the remote areas of their LV. Concomitantly, in remote myocardium of MI-induced rats, ghrelin enhanced endoplasmic reticulum intracellular organelles count, decreased number of atrophied nuclei and phagocytes, diminished the irregularity in the nuclear membranes and inhibited chromatin condensation. In conclusion, in addition to the physiological, biochemical and molecular evidence provided, this is the first study that confirms the anti-apoptotic effect of ghrelin in the remote myocardium of the LV during late MI at the level of ultra-structural changes. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Regulation of NK92-MI cell cytotoxicity by substance P.

PubMed

Fu, W X; Qin, B; Zhou, A P; Yu, Q Y; Huang, Q J; Liang, Z F

2011-08-01

The neuropeptide substance P (SP) can regulate a number of immunological functions in vitro and in vivo and may regulate natural killer (NK) cell activity. Here, we investigated whether SP has a role in regulating NK92-MI cell function in vitro, and how it influences NK cell activity. We found that SP dose dependently increased the cytotoxicity of NK92-MI cells and had a maximal effect at a concentration of 10(-12) and 10(-10) m. Furthermore, the expression of cytotoxic-associated molecules (perforin, granzyme) and activating receptor NKp46 [a member of natural cytotoxicity receptors (NCRs)] was observed to be upregulated by SP at optimal concentration, at which SP enhanced the cytotoxicity of NK92-MI cells. Neurokinin-1 receptor (NK-1R), a functional receptor of SP, was found on NK92-MI cells, and the observed effects of SP on NK92-MI cells could be more partially blocked by an NK-1R antagonist. Our data suggest that SP induces NK92-MI cell cytotoxicity by directly increasing the expression of cytotoxic granules and upregulates NK92-MI cell receptor-mediated functions indirectly. Thus, SP may regulate NK cell function mainly through NK-1R. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.

Effects of murine leukemia virus env gene proteins on macrophage-mediated cytotoxicity in vitro

NASA Technical Reports Server (NTRS)

Chapes, S. K.; Takemoto, L. J.; Spooner, B. S. (Principal Investigator)

1991-01-01

F5b Tumor cells were incubated with concentrated culture supernatants taken from cells resistant (F5m) or sensitive (F5b) to contact-dependent macrophage cytotoxicity. Macrophage cell line B6MP102 and murine peritoneal macrophages killed targets incubated with supernatants taken from sensitive cells but poorly killed cells incubated in supernatants isolated from resistant cells. Membranes from cells resistant to macrophage killing, F5m, were fused into F5b cells. The fused F5b cells were killed significantly less than F5b cells fused with F5b cell membranes or untreated F5b cells. The decreased killing of F5b cells corresponded to increased concentrations of gp70(a) molecules on F5b cells. Affinity purified gp70(a) was added to cytotoxicity assays but failed to inhibit macrophage cytotoxicity. P15E molecules were detectable on both F5b and F5m cells. In addition, a synthetic peptide found to exhibit the inhibitory properties of p15E was added to cytotoxicity assays. P15E synthetic peptide also did not inhibit macrophage cytotoxicity. Therefore, env gene proteins of murine leukemia virus do not appear responsible for inducing tumor cell resistance to activated macrophage contact-dependent cytotoxicity.

Collagen Fibrils and Proteoglycans of Macular Dystrophy Cornea: Ultrastructure and 3D Transmission Electron Tomography.

PubMed

Akhtar, Saeed; Alkatan, Hind M; Kirat, Omar; Khan, Adnan A; Almubrad, Turki

2015-06-01

We report the ultrastructure and 3D transmission electron tomography of collagen fibrils (CFs), proteoglycans (PGs), and microfibrils within the CF of corneas of patients with macular corneal dystrophy (MCD). Three normal corneas and three MCD corneas from three Saudi patients (aged 25, 31, and 49 years, respectively) were used for this study. The corneas were processed for light and electron microscopy studies. 3D images were composed from a set of 120 ultrastructural images using the program "Composer" and visualized using the program "Visuliser Kai". 3D image analysis of MCD cornea showed a clear organization of PGs around the CF at very high magnification and degeneration of the microfibrils within the CF. Within the MCD cornea, the PG area in the anterior stroma was significantly larger than in the middle and posterior stroma. The PG area in the MCD cornea was significantly larger compared with the PG area in the normal cornea. The CF diameter and inter-fibrillar spacing of the MCD cornea were significantly smaller compared with those of the normal cornea. Ultrastructural 3D imaging showed that the production of unsulfated keratin sulfate (KS) may lead to the degeneration of micro-CFs within the CFs. The effect of the unsulfated KS was higher in the anterior stroma compared with the posterior stroma.

Endocrine cells in human Bartholin's glands. An immunohistochemical and ultrastructural analysis.

PubMed

Fetissof, F; Arbeille, B; Bellet, D; Barre, I; Lansac, J

1989-01-01

Endocrine cells were investigated in human Bartholin's glands by use of histochemical, immunohistochemical and ultrastructural methods. Endocrine cells represent normal constituents of these glands, being mainly distributed throughout the transitional epithelium of the major excretory duct; however, single elements are dispersed among the acinar lobules. Serotonin-, calcitonin-, katacalcin-, bombesin- and alpha-hCG-immunoreactive cells were recognized, with serotonin-immunoreactive cells predominating. Co-expression of calcitonin, katacalcin or alpha-hCG with serotonin was observed in single endocrine cells. At the ultrastructural level, these cells are richly granulated and show typical neuroendocrine features. Bartholin's glands display an endocrine profile quite similar to that of other cloacal-derived tissues.

Evaluation of differential cytotoxic effects of the oil spill dispersant Corexit 9500.

PubMed

Zheng, Mengyuan; Ahuja, Manuj; Bhattacharya, Dwipayan; Clement, T Prabhakar; Hayworth, Joel S; Dhanasekaran, Muralikrishnan

2014-01-30

The British Petroleum (BP) oil spill has raised several ecological and health concerns. As the first response, BP used a chemical dispersant, Corexit-9500, to disperse the crude oil in the Gulf of Mexico to limit shoreline contamination problems. Nevertheless, portions of this oil/Corexit mixture reached the shoreline and still remain in various Gulf shore environments. The use of Corexit itself has become a significant concern since its impacts on human health and environment is unclear. In this study, in vitro cytotoxic effects of Corexit were evaluated using different mammalian cells. Under serum free conditions, the LC50 value for Corexit in BL16/BL6 cell was 16 ppm, in 1321N1 cell was 33 ppm, in H19-7 cell was 70 ppm, in HEK293 was 93 ppm, and in HK-2 cell was 95 ppm. With regard to the mechanisms of cytotoxicity, we hypothesize that Corexit can possibly induce cytotoxicity in mammalian cells by altering the intracellular oxidative balance and inhibiting mitochondrial functions. Corexit induced increased reactive oxygen species and lipid peroxide levels; also, it depleted glutathione content and altered catalase activity in H19-7 cells. In addition, there was mitochondrial complex-I inhibition and increase in the pro-apoptotic factors including caspase-3 and BAX expression. The experimental results show changes in intracellular oxidative radicals leading to mitochondrial dysfunctions and apoptosis in Corexit treatments, possibly contributing to cell death. Our findings raise concerns about using large volumes of Corexit, a potential environmental toxin, in sensitive ocean environments. Copyright © 2013 Elsevier Inc. All rights reserved.

Gingerol Synergizes the Cytotoxic Effects of Doxorubicin against Liver Cancer Cells and Protects from Its Vascular Toxicity.

PubMed

Al-Abbasi, Fahad A; Alghamdi, Eman A; Baghdadi, Mohammed A; Alamoudi, Abdulmohsin J; El-Halawany, Ali M; El-Bassossy, Hany M; Aseeri, Ali H; Al-Abd, Ahmed M

2016-07-08

Hydroxyphenylalkanes and diarylheptanoids possess potential therapeutic value in different pathophysiological conditions, such as malignancy. In the current study, naturally isolated hydroxyphenylalkane and diarylheptanoid compounds were investigated for potential chemo-modulatory effects in addition to potential vascular protective roles with doxorubicin. Diarylheptanoids showed stronger antioxidant effects, in comparison to hydroxyphenylalkanes, as demonstrated by DPPH assay and amelioration of CCl₄-induced disturbed intracellular GSH/GSSG balance. Shogaol and 4'-methoxygingerol showed considerable cytotoxic effects against HCT116, HeLa, HepG2 and MCF7 cells, with IC50 values ranging from 3.1 to 19.4 µM. Gingerol significantly enhanced the cytotoxic profile of doxorubicin against HepG₂ and Huh7, cells decreasing its IC50s by 10- and 4-fold, respectively. Cell cycle distribution was studied using DNA cytometry. Doxorubicin alone induced cell accumulation at S-phase and G₂/M-phase, while in combination with gingerol it significantly induced cell cycle arrest at the G₂/M-phase. Additionally, the vascular protective effect of gingerol against doxorubicin (10 µM) was examined on isolated aortic rings. Co-incubation with 6-gingerol (30 µM) completely blocked the exaggerated vasoconstriction and impaired vascular relaxation induced by doxorubicin. In conclusion, despite its relatively weak antioxidant properties, gingerol protected from DOX-induced vascular damage, apparently not through a ROS scavenging mechanism. Besides, gingerol synergized the cytotoxic effects of DOX against liver cancer cells without influencing the cellular pharmacokinetics.

ULTRASTRUCTURAL STUDIES OF VASOPRESSIN EFFECT ON ISOLATED PERFUSED RENAL COLLECTING TUBULES OF THE RABBIT

PubMed Central

Ganote, Charles E.; Grantham, Jared J.; Moses, Harold L.; Burg, Maurice B.; Orloff, Jack

1968-01-01

Isolated cortical collecting tubules from rabbit kidney were studied during perfusion with solutions made either isotonic or hypotonic to the external bathing medium. Examination of living tubules revealed a reversible increase in thickness of the cellular layer, prominence of lateral cell membranes, and formation of intracellular vacuoles during periods of vasopressin-induced osmotic water transport. Examination in the electron microscope revealed that vasopressin induced no changes in cell structure in collecting tubules in the absence of an osmotic difference and significant bulk water flow across the tubule wall. In contrast, tubules fixed during vasopressin-induced periods of high osmotic water transport showed prominent dilatation of lateral intercellular spaces, bulging of apical cell membranes into the tubular lumen, and formation of intracellular vacuoles. It is concluded that the ultrastructural changes are secondary to transepithelial bulk water flow and not to a direct effect of vasopressin on the cells, and that vasopressin induces osmotic flow by increasing water permeability of the luminal cell membrane. The lateral intercellular spaces may be part of the pathway for osmotically induced transepithelial bulk water flow. PMID:4867134

Factors involved in the cytotoxicity of kaolinite towards macrophages in vitro.

PubMed Central

Davies, R

1983-01-01

The cytotoxicity of a high purity Cornish kaolinite toward mouse peritoneal macrophages in vitro was examined. The material was cytotoxic towards these cells, the activity could be decreased substantially by pretreating the dust with poly(2-vinylpyridine N-oxide). Pretreatment of the dusts with poly(acrylic acid) had a small effect on cytotoxicity, but combinations of the polymer treatments virtually abolished the material's biological activity towards macrophages. These studies indicated that the cytotoxicity of kaolinite is not due to its flakelike morphology. Images FIGURE 1. PMID:6641658

Cytotoxicity of selenium nanoparticles in rat dermal fibroblasts

PubMed Central

Ramos, Joseph F; Webster, Thomas J

2012-01-01

Background: Ventilator-associated pneumonia is a deadly nosocomial infection caused by contaminated endotracheal tubes. It has been shown that polyvinyl chloride (PVC, the endotracheal tube substrate) coated with elemental selenium nanoparticles reduces bacterial adherence and proliferation on PVC by over 99%. However, it is not known if selenium nanoparticles elicit a cytotoxic effect in vitro. The purpose of this study was to investigate the cytotoxic effects of PVC coated with selenium nanoparticles on fibroblasts, which are mammalian cells central to endotracheal tube intubation. Methods: Different concentrations of selenium nanoparticles were precipitated onto the PVC surface by reduction of selenium salts using glutathione. Characterization of PVC coated with selenium nanoparticles was done by scanning electron microscopy, energy dispersive x-ray, and contact angle measurements. For the cytotoxicity experiments, fibroblasts were seeded at a density of 5000 cm2 onto PVC coated with three different concentrations of selenium nanoparticles (high, medium, low) and incubated for 4 hours (adhesion) as well as for 24 hours and 72 hours (proliferation). The half-maximal inhibitory concentration (IC50) value was determined after 72 hours using an ultrahigh concentration. MTT assays were used to assess cell viability at the indicated time points. Results: The three concentrations of selenium nanoparticles did not elicit a cytotoxic effect after 72 hours (P < 0.01, n = 3). It was found that the IC50value was at the ultrahigh concentration of selenium nanoparticles. The nanoparticulate elemental selenium concentration previously shown to decrease the function of bacteria was shown not to cause a cytotoxic effect on fibroblasts in vitro. Conclusion: These findings demonstrate great selectivity between bacteria and healthy cells, and are a viable option for coating endotracheal tubes in order to prevent ventilator-associated pneumonia. PMID:22915842

In vitro cytotoxicity of Manville Code 100 glass fibers: Effect of fiber length on human alveolar macrophages

PubMed Central

Zeidler-Erdely, Patti C; Calhoun, William J; Ameredes, Bill T; Clark, Melissa P; Deye, Gregory J; Baron, Paul; Jones, William; Blake, Terri; Castranova, Vincent

2006-01-01

Background Synthetic vitreous fibers (SVFs) are inorganic noncrystalline materials widely used in residential and industrial settings for insulation, filtration, and reinforcement purposes. SVFs conventionally include three major categories: fibrous glass, rock/slag/stone (mineral) wool, and ceramic fibers. Previous in vitro studies from our laboratory demonstrated length-dependent cytotoxic effects of glass fibers on rat alveolar macrophages which were possibly associated with incomplete phagocytosis of fibers ≥ 17 μm in length. The purpose of this study was to examine the influence of fiber length on primary human alveolar macrophages, which are larger in diameter than rat macrophages, using length-classified Manville Code 100 glass fibers (8, 10, 16, and 20 μm). It was hypothesized that complete engulfment of fibers by human alveolar macrophages could decrease fiber cytotoxicity; i.e. shorter fibers that can be completely engulfed might not be as cytotoxic as longer fibers. Human alveolar macrophages, obtained by segmental bronchoalveolar lavage of healthy, non-smoking volunteers, were treated with three different concentrations (determined by fiber number) of the sized fibers in vitro. Cytotoxicity was assessed by monitoring cytosolic lactate dehydrogenase release and loss of function as indicated by a decrease in zymosan-stimulated chemiluminescence. Results Microscopic analysis indicated that human alveolar macrophages completely engulfed glass fibers of the 20 μm length. All fiber length fractions tested exhibited equal cytotoxicity on a per fiber basis, i.e. increasing lactate dehydrogenase and decreasing chemiluminescence in the same concentration-dependent fashion. Conclusion The data suggest that due to the larger diameter of human alveolar macrophages, compared to rat alveolar macrophages, complete phagocytosis of longer fibers can occur with the human cells. Neither incomplete phagocytosis nor length-dependent toxicity was observed in fiber

Genotoxic and cytotoxic effects of doxorubicin and silymarin on human hepatocellular carcinoma cells.

PubMed

Yurtcu, E; İşeri, Öd; Sahin, Fi

2014-12-01

The aim of this study was to investigate genotoxic and cytotoxic effects of doxorubicin, silymarin, or in combination on HepG2 cells for 24 and 48 h. Both doxorubicin and silymarin caused dose-dependent inhibition of cell proliferation. After 48 h of treatment, doxorubicin application caused dramatically increased ratio of apoptotic cells. Both 24 and 48 h of silymarin and doxorubicin-silymarin combination caused significant increases in the rate of apoptotic cells. Applications of doxorubicin and silymarin separately for 24 h led to deoxyribonucleic acid (DNA) damages. After 48 h of incubation, doxorubicin-induced genotoxic damage was 2-fold higher than the silymarin-induced damage. After 24 and 48 h, DNA damage in response to combined applications of doxorubicin and silymarin was indifferent from silymarin- and doxorubicin-induced damage respectively. There was not any difference in genotoxicity levels between incubation periods in combined applications of doxorubicin and silymarin. Lipid peroxidation levels increased in all applications. Biopharmacotherapy with chemotherapeutic agents are of interest in the issue of adjuvant therapy. Here, we demonstrate in vitro potential genotoxic and cytotoxic antitumor effect of silymarin on HepG2 cells at achievable plasma level concentrations. © The Author(s) 2014.

CYTOTOXICITY AND MUTAGENESIS METHODS FOR EVALUATING TOXICITY REMOVAL FROM WASTEWATERS

EPA Science Inventory

This project was a feasibility study of the effectiveness of a mammalian cell cytotoxicity assay and a mammalian cell mutagenesis assay for monitoring the toxicity and mutagenicity of influent and effluent wastewater at treatment plants. In the cytotoxicity assay, ambient samples...

Malignant lymphoma of the cervix uteri: histology and ultrastructure.

PubMed Central

Carr, I; Hill, A S; Hancock, B; Neal, F F

1976-01-01

Two cases of primary lymphoma of the cervix uteri are described. Both responded to radiotherapy; both were composed at the ultrastructural level of mature macrophages and immature, apparently neoplastic lymphoreticular cells and are classified as reticulum cell lymphoma. Images PMID:783205

First investigation of the collagen D-band ultrastructure in fossilized vertebrate integument.

PubMed

Lingham-Soliar, Theagarten; Wesley-Smith, James

2008-10-07

The ultrastructure of dermal fibres of a 200Myr thunniform ichthyosaur, Ichthyosaurus, specifically the 67nm axial repeat D-banding of the fibrils, which characterizes collagen, is presented for the first time by means of scanning electron microscopy (SEM) analysis. The fragment of material investigated is part of previously described fossilized skin comprising an architecture of layers of oppositely oriented fibre bundles. The wider implication, as indicated by the extraordinary quality of preservation, is the robustness of the collagen molecule at the ultrastructural level, which presumably contributed to its survival during the initial processes of decomposition prior to mineralization. Investigation of the elemental composition of the sample by SEM-energy dispersive X-ray spectroscopy indicates that calcite and phosphate played important roles in the rapid mineralization and fine replication of the collagen fibres and fibrils. The exceedingly small sample used in the investigation and high level of information achieved indicate the potential for minimal damage to prized museum specimens; for example, ultrastructural investigations by SEM may be used to help resolve highly contentious questions, for example, 'protofeathers' in the Chinese dinosaurs.

Annatto Tocotrienol Induces a Cytotoxic Effect on Human Prostate Cancer PC3 Cells via the Simultaneous Inhibition of Src and Stat3.

PubMed

Sugahara, Ryosuke; Sato, Ayami; Uchida, Asuka; Shiozawa, Shinya; Sato, Chiaki; Virgona, Nantiga; Yano, Tomohiro

2015-01-01

Prostate cancer is one of the most frequently occurring cancers and often acquires the potential of androgen-independent growth as a malignant phenotype. Androgen-independent prostate cancer has severe chemoresistance towards conventional chemotherapeutic agents, so a new treatment approach is required for curing such prostate cancer. In this context, the present study was undertaken to check if annatto tocotrienol (main component δ-tocotrienol) could suppress cell growth in human prostate cancer (PC3, androgen-independent type) cells via the inhibition of Src and Stat3. The tocotrienol showed cytotoxic effects on PC3 cells in a dose-dependent manner, and the effect depended on G1 arrest in the cell cycle and subsequent induction of apoptosis. In a cytotoxic dose, the tocotrienol suppressed cellular growth via the simultaneous inhibition of Src and Stat3. Similarly, the treatment combination of both Src and Stat3 inhibitors induced cytotoxic effects in PC3 cells in an additive manner compared to each by itself. With respect to cell cycle regulation and the induction of apoptosis, the combination treatment showed a similar effect to that of the tocotrienol treatment. These results suggest that annatto tocotrienol effectively induces cytotoxicity in androgen-independent prostate cancer cells via the suppression of Src and Stat3.

Relationship between the adjuvant and cytotoxic effects of the positive charges and polymerization in liposomes.

PubMed

Gasparri, Julieta; Speroni, Lucía; Chiaramoni, Nadia Silvia; del Valle Alonso, Silvia

2011-06-01

Vaccine development today encounters a main obstacle, which is the need for effective adjuvants suitable for clinical trials. Aluminum salts, discovered 70 years ago and, very recently, MF59, are the only types of adjuvants currently used in vaccines licensed by the U.S. Food and Drug Administration. Liposomes represent an alternative approach to vaccine adjuvants. In this article, we describe the inflammatory response and biological effect of polymerization and the addition of positive charges in liposome formulations. Nonpolymerized cationic (NP(+)) liposomes significantly reduce metabolism in Vero cells after 24 hours. Correspondingly, both NP(+) and polymerized cationic (P(+)) liposomes reduce cell viability following a 48-hour incubation. Similar results were obtained with cells from the peritoneal cavities of mice. Paradoxically, those liposomes that presented clearly cytostatic or cytotoxic effects in vitro stimulated metabolism and had a mitogenic effect in vivo. Finally, the adjuvant effect was tested by immunization in BALB/c mice. The major effect was obtained with NP(+) liposomes. Accordingly, we also demonstrated that NP(+) liposomes injected into the dermis produced an outstanding inflammatory reaction, showing the histopathological characteristics of an inoculation granuloma. Thus, positive charge would play an important role in the immunoadjuvant effect of liposomes by conferring them cytotoxic capacity.

Ultrastructure, biology, and phylogenetic relationships of kinorhyncha.

PubMed

Neuhaus, Birger; Higgins, Robert P

2002-07-01

The article summarizes current knowledge mainly about the (functional) morphology and ultrastructure, but also about the biology, development, and evolution of the Kinorhyncha. The Kinorhyncha are microscopic, bilaterally symmetrical, exclusively free-living, benthic, marine animals and ecologically part of the meiofauna. They occur throughout the world from the intertidal to the deep sea, generally in sediments but sometimes associated with plants or other animals. From adult stages 141 species are known, but 38 species have been described from juvenile stages. The trunk is arranged into 11 segments as evidenced by cuticular plates, sensory spots, setae or spines, nervous system, musculature, and subcuticular glands. The ultrastructure of several organ systems and the postembryonic development are known for very few species. Almost no data are available about the embryology and only a single gene has been sequenced for a single species. The phylogenetic relationships within Kinorhyncha are unresolved. Priapulida, Loricifera, and Kinorhyncha are grouped together as Scalidophora, but arguments are found for every possible sistergroup relationship within this taxon. The recently published Ecdysozoa hypothesis suggests a closer relationship of the Scalidophora, Nematoda, Nematomorpha, Tardigrada, Onychophora, and Arthropoda.

Cytotoxicity of modified glass ionomer cement on odontoblast cells.

PubMed

Chen, Song; Mestres, Gemma; Lan, Weihua; Xia, Wei; Engqvist, Håkan

2016-07-01

Recently a modified glass ionomer cement (GIC) with enhanced bioactivity due to the incorporation of wollastonite or mineral trioxide aggregate (MTA) has been reported. The aim of this study was to evaluate the cytotoxic effect of the modified GIC on odontoblast-like cells. The cytotoxicity of a conventional GIC, wollastonite modified GIC (W-mGIC), MTA modified GIC (M-mGIC) and MTA cement has been evaluated using cement extracts, a culture media modified by the cement. Ion concentration and pH of each material in the culture media were measured and correlated to the results of the cytotoxicity study. Among the four groups, conventional GIC showed the most cytotoxicity effect, followed by W-mGIC and M-mGIC. MTA showed the least toxic effect. GIC showed the lowest pH (6.36) while MTA showed the highest (8.62). In terms of ion concentration, MTA showed the largest Ca(2+) concentration (467.3 mg/L) while GIC showed the highest concentration of Si(4+) (19.9 mg/L), Al(3+) (7.2 mg/L) and Sr(2+) (100.3 mg/L). Concentration of F(-) was under the detection limit (0.02 mg/L) for all samples. However the concentrations of these ions are considered too low to be toxic. Our study showed that the cytotoxicity of conventional GIC can be moderated by incorporating calcium silicate based ceramics. The modified GIC might be promising as novel dental restorative cements.

Gastroprotective effect and cytotoxicity of natural and semisynthetic labdane diterpenes from Araucaria araucana resin.

PubMed

Schmeda-Hirschmann, Guillermo; Astudillo, Luis; Sepúlveda, Beatriz; Rodríguez, Jaime A; Theoduloz, Cristina; Yáñez, Tania; Palenzuela, José Antonio

2005-01-01

The resin of the tree Araucaria araucana (Araucariaceae) is used by the Mapuche Amerindians in southern Chile and Argentina to treat ulcers and has been shown to display a gastroprotective effect in animal models. A study was undertaken to isolate, identify and assess the gastroprotective effect of the resin constituents and its semisynthetic derivatives as well as to evaluate the cytotoxicity of the products in cell cultures. Eleven diterpenes (ten labdane and a pimarane) were isolated from a resin sample collected in Chile. The labdane derivatives 15-acetoxylabd-8(17)-en-19-ol as well as 15,19-diacetoxylabd-8(17)-en are reported for the first time as natural products. Six diterpenes previously described from other plant sources are reported for the first time for the A. araucana resin. The structure of all compounds was elucidated by spectroscopic means. Some 24 diterpenes isolated/prepared in amounts over 10 mg were evaluated for gastroprotective effects in the ethanol/HCl-induced ulcer model in mice at 100 mg/kg. The highest gastroprotective activities were provided by 15-hydroxyimbricatolal, 15-acetoxyimbricatolal, 15-acetoxylabd-8(17)-en-19-oic acid methyl ester and 15-acetoxy-19-labdanoic acid, all of them being as active as the reference drug lansoprazole at 20 mg/kg. The cytotoxicity of 30 diterpenes as well as lansoprazole was assessed towards human lung fibroblasts (MRC-5) and 26 compounds were evaluated on the human gastric epithelial cell line AGS by means of the neutral red uptake assay. A concentration-dependent cell viability inhibition was found with IC50 values ranging from 27 up to > 1000 microM. The relationship between the cytotoxicity data and lipophilicity of the products is also discussed.

Pathogenesis of trimethyltin neuronal toxicity. Ultrastructural and cytochemical observations.

PubMed Central

Bouldin, T. W.; Goines, N. D.; Bagnell, R. C.; Krigman, M. R.

1981-01-01

The ultrastructural cytopathologic and cytochemical effects of trimethyltin (TMT) neurotoxicity were delineated in hippocampal and pyriform neurons of acutely intoxicated adult rats. TMT produced neuronal necrosis that preferentially involved hippocampal formation pyriform cortex. The first subcellular alterations were multifocal collection of dense-cored vesicles and tubules and membrane-delimited vacuoles in the cytoplasm of the perikaryon and proximal dendrite. Ultrastructural cytochemical examination revealed that the vesicles and tubules had acid phosphatase activity analagous to Golgi-associated endoplasmic reticulum (GERL). Shortly after the appearance of the GERL-like vesicles and tubules, autophagic vacuoles and polymorphic dense bodies accumulated in the neuronal cytoplasm. Some dense bodies appeared to arise from the dense-cored tubules. Neuronal necrosis was characterized by increased electron density of the cytoplasm and large, electron-dense intranuclear masses. Alterations of mitochondria and other organelles were not observed in the early stages of cell injury. No light- or electron-microscopic alterations were found in liver or kidney. Comparable subcellular alterations were observed in adult and neonatal rats chronically intoxicated with TMT. A series of other trialkyl and tricyclic tins and dimethyltin did not produce similar pathologic findings. The GERL-like accumulations are unique in neuronal cytopathology. These findings suggests that GERL and autophagy play an important role in the pathogenesis of TMT-induced neuronal injury. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:7294153

Ultrastructure of sea urchin calcified tissues after high-pressure freezing and freeze substitution.

PubMed

Ameye, L; Hermann, R; Dubois, P

2000-08-01

The improvements brought by high-pressure freezing/freeze substitution fixation methods to the ultrastructural preservation of echinoderm mineralized tissues are investigated in developing pedicellariae and teeth of the echinoid Paracentrotus lividus. Three freeze substitution (FS) protocols were tested: one in the presence of osmium tetroxide, one in the presence of uranyl acetate, and the last in the presence of gallic acid. FS in the presence of osmium tetroxide significantly improved cell ultrastructure preservation and should especially be used for ultrastructural studies involving vesicles and the Golgi apparatus. With all protocols, multivesicular bodies, suggested to contain Ca(2+), were evident for the first time in skeleton-forming cells. FS in the presence of gallic acid allowed us to confirm the structured and insoluble character of a part of the organic matrix of mineralization in the calcification sites of the tooth, an observation which modifies the current understanding of biomineralization control in echinoderms. Copyright 2000 Academic Press.

Cytotoxicity associated with electrospun polyvinyl alcohol.

PubMed

Pathan, Saif G; Fitzgerald, Lisa M; Ali, Syed M; Damrauer, Scott M; Bide, Martin J; Nelson, David W; Ferran, Christiane; Phaneuf, Tina M; Phaneuf, Matthew D

2015-11-01

Polyvinyl alcohol (PVA) is a synthetic, water-soluble polymer, with applications in industries ranging from textiles to biomedical devices. Research on electrospinning of PVA has been targeted toward optimizing or finding novel applications in the biomedical field. However, the effects of electrospinning on PVA biocompatibility have not been thoroughly evaluated. In this study, the cytotoxicity of electrospun PVA (nPVA) which was not crosslinked after electrospinning was assessed. PVA polymers of several molecular weights were dissolved in distilled water and electrospun using the same parameters. Electrospun PVA materials with varying molecular weights were then dissolved in tissue culture medium and directly compared against solutions of nonelectrospun PVA polymer in human coronary artery smooth muscle cells and human coronary artery endothelial cells cultures. All nPVA solutions were cytotoxic at a threshold molar concentration that correlated with the molecular weight of the starting PVA polymer. In contrast, none of the nonelectrospun PVA solutions caused any cytotoxicity, regardless of their concentration in the cell culture. Evaluation of the nPVA material by differential scanning calorimetry confirmed that polymer degradation had occurred after electrospinning. To elucidate the identity of the nPVA component that caused cytotoxicity, nPVA materials were dissolved, fractionated using size exclusion columns, and the different fractions were added to HCASMC and human coronary artery endothelial cells cultures. These studies indicated that the cytotoxic component of the different nPVA solutions were present in the low-molecular-weight fraction. Additionally, the amount of PVA present in the 3-10 kg/mol fraction was approximately sixfold greater than that in the nonelectrospun samples. In conclusion, electrospinning of PVA resulted in small-molecular-weight fractions that were cytotoxic to cells. This result demonstrates that biocompatibility of electrospun

Cytotoxic activity of some medicinal plants from hamedan district of iran.

PubMed

Behzad, Sahar; Pirani, Atefeh; Mosaddegh, Mahmoud

2014-01-01

Medicinal plants have been investigated for possible anti-cancer effects. The aim of the present study was to examine the cytotoxic activity of several medicinal plants on different tumor cell lines. 11 selected plant species which have been used in folkloric prescriptions were collected from different sites of Hamedan district of Iran. The methanolic extracts of the plants were prepared and their cytotoxic effects on four human cancer cell lines (A549, human lung adenocarcinoma; MCF7, human breast adenocarcinoma; HepG2, hepatocellular carcinoma and HT-29, human colon carcinoma) and one normal cell line (MDBK, bovine kidney) were examined using the MTT assay. Three of these were exhibited antiproliferative activity against one or more of the cell lines. The extract from Primula auriculata demonstrated the highest cytotoxicity with IC50 of 25.79, 35.79 and 43.34 μg.mL-1 against MCF7, HepG2 and HT- 29 cells, respectively. For some of the plants, their traditional use was correlated with the cytotoxic results, whereas for others the results may support the non-cytotoxicity of species used traditionally as natural remedies. The cytotoxic species could be considered as potential of anticancer compounds.

Celecoxib-Induced Cytotoxic Effect Is Potentiated by Inhibition of Autophagy in Human Urothelial Carcinoma Cells

PubMed Central

Ho, I-Lin; Chang, Hong-Chiang; Chuang, Yuan-Ting; Lin, Wei-Chou; Lee, Ping-Yi; Chang, Shih-Chen; Chiang, Chih-Kang; Pu, Yeong-Shiau; Chou, Chien-Tso; Hsu, Chen-Hsun; Liu, Shing-Hwa

2013-01-01

Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, can elicit anti-tumor effects in various malignancies. Here, we sought to clarify the role of autophagy in celecoxib-induced cytotoxicity in human urothelial carcinoma (UC) cells. The results shows celecoxib induced cellular stress response such as endoplasmic reticulum (ER) stress, phosopho-SAPK/JNK, and phosopho-c-Jun as well as autophagosome formation in UC cells. Inhibition of autophagy by 3-methyladenine (3-MA), bafilomycin A1 or ATG7 knockdown potentiated celecoxib-induced apoptosis. Up-regulation of autophagy by rapamycin or GFP-LC3B-transfection alleviated celecoxib-induced cytotoxicity in UC cells. Taken together, the inhibition of autophagy enhances therapeutic efficacy of celecoxib in UC cells, suggesting a novel therapeutic strategy against UC. PMID:24349176

Ultrastructural changes in sweet orange with symptoms of huanglongbing

USDA-ARS?s Scientific Manuscript database

Citrus greening (Huanglongbing [HLB]) is one of the most destructive citrus diseases worldwide. To better understand the ultrastructural changes of sweet orange seedlings in response to infection, anatomical analyses of HLB-infected sweet orange were carried out by light and electron microscopy. A...

Label-free visualization of ultrastructural features of artificial synapses via cryo-EM.

PubMed

Gopalakrishnan, Gopakumar; Yam, Patricia T; Madwar, Carolin; Bostina, Mihnea; Rouiller, Isabelle; Colman, David R; Lennox, R Bruce

2011-12-21

The ultrastructural details of presynapses formed between artificial substrates of submicrometer silica beads and hippocampal neurons are visualized via cryo-electron microscopy (cryo-EM). The silica beads are derivatized by poly-d-lysine or lipid bilayers. Molecular features known to exist at presynapses are clearly present at these artificial synapses, as visualized by cryo-EM. Key synaptic features such as the membrane contact area at synaptic junctions, the presynaptic bouton containing presynaptic vesicles, as well as microtubular structures can be identified. This is the first report of the direct, label-free observation of ultrastructural details of artificial synapses.

Plasmid-determined cytotoxicity in Yersinia pestis and Yersinia pseudotuberculosis.

PubMed Central

Goguen, J D; Walker, W S; Hatch, T P; Yother, J

1986-01-01

Yersinia pestis KIM5 was found to be cytotoxic for the IC21 and P388D1 mouse macrophage cell lines, as well as for resident peritoneal macrophages from C57BL/6 mice. Affected cells phagocytosed KIM5 inefficiently, became spherical, detached readily from culture dishes, and retained 51Cr poorly. The cytotoxic effect was dependent on the presence of the 75-kilobase plasmid pCD1. Because this plasmid also encodes the low calcium response (LCR), three Mu d1 insertion mutants previously shown to be LCR- and of reduced virulence in mice were examined for cytotoxicity; all were found to be atoxic. The insertions in these mutants lie within three distinct LCR loci (lcrB, C, and D). Like LCR, cytotoxicity was expressed only at 37 degrees C. Unlike LCR, it was not influenced by Ca2+ concentration, indicating that the V and W antigens are probably not involved. Yersinia pseudotuberculosis was found to have a similar plasmid-dependent cytotoxicity. Thus, biological activity observed as cytotoxicity in vitro may well be a common feature contributing to virulence of the yersiniae. Images PMID:3949380

Rat limb unloading - Soleus histochemistry, ultrastructure, and electromyography

NASA Technical Reports Server (NTRS)

Riley, D. A.; Slocum, G. R.; Bain, J. L. W.; Sedlak, F. R.; Sowa, T. E.

1990-01-01

The effects of hindlimb unloading on rat-soleus histochemisty, ultrastructure, and electromyogram (EMG) activity were investigated. It was found that, after 14 days of tail suspension, the area of type I and type IIa muscle fibers decreased by 63 and 47 percent, respectively, mainly due to the degradation of subsarcolemmal mitochondria and myofibrils. After 10 days, 3 percent of type IIa fibers exhibited segmental necrosis. After four days, video monitoring revealed abnormal plantar flexion of the hindfeet, which shortened the soleus working range. The EMG activity shifted from tonic to phasic, and aggregate activity decreased drastically after only seven days. The results indictate that the pathological changes in the soleus resulted from unloaded contractions, reduced use, compromised blood flow, and shortened working length.

Effects of Chinese herbal medicine Yinsiwei compound on spatial learning and memory ability and the ultrastructure of hippocampal neurons in a rat model of sporadic Alzheimer disease.

PubMed

Diwu, Yong-chang; Tian, Jin-zhou; Shi, Jing

2011-02-01

To study the effects of Chinese herbal medicine Yinsiwei compound (YSW) on spatial learning and memory ability in rats with sporadic Alzheimer disease (SAD) and the ultrastructural basis of the hippocampal neurons. A rat model of SAD was established by intracerebroventricular injection of streptozotocin. The rats were divided into six groups: sham-operation group, model group, donepezil control group, and YSW low, medium and high dose groups. Drug interventions were started on the 21st day after modeling and each treatment group was given the corresponding drugs by gavage for two months. Meanwhile, the model group and the sham-operation group were given the same volume of distilled water by gavage once a day for two months. The Morris water maze was adopted to test spatial learning and memory ability of the rats. The place navigation test and the spatial probe test were conducted. The escape latency, total swimming distance and swimming time in the target quadrant of the rats were recorded. Also, the hippocampus tissues of rats were taken out and the ultrastructure of hippocampus neurons were observed by an electron microscope. In the place navigation test, compared with the model group, the mean escape latency and the total swimming distance of the donepezil group and the YSW low, medium and high dose groups were significantly shortened (P<0.05 or P<0.01). In the space probe test, the swimming time of each treatment group in the target quadrant was significantly longer than that of the model group (P<0.05 or P<0.01). For most of the test period, the donepezil group had no significant change compared with the YSW low, medium and high dose groups, respectively. The ultrastructure of the hippocampus neurons under the electron microscope also confirmed the efficacy of the drug treatment. Chinese herbal medicine YSW compound can improve spatial learning and memory impairment of rats with SAD. The ultrastructural basis may be that it can protect the microtubule

Altered UV absorbance and cytotoxicity of chlorinated sunscreen agents.

PubMed

Sherwood, Vaughn F; Kennedy, Steven; Zhang, Hualin; Purser, Gordon H; Sheaff, Robert J

2012-12-01

Sunscreens are widely utilized due to the adverse effects of ultraviolet (UV) radiation on human health. The safety of their active ingredients as well as that of any modified versions generated during use is thus of concern. Chlorine is used as a chemical disinfectant in swimming pools. Its reactivity suggests sunscreen components might be chlorinated, altering their absorptive and/or cytotoxic properties. To test this hypothesis, the UV-filters oxybenzone, dioxybenzone, and sulisobenzone were reacted with chlorinating agents and their UV spectra analyzed. In all cases, a decrease in UV absorbance was observed. Given that chlorinated compounds can be cytotoxic, the effect of modified UV-filters on cell viability was examined. Chlorinated oxybenzone and dioxybenzone caused significantly more cell death than unchlorinated controls. In contrast, chlorination of sulisobenzone actually reduced cytotoxicity of the parent compound. Exposing a commercially available sunscreen product to chlorine also resulted in decreased UV absorbance, loss of UV protection, and enhanced cytotoxicity. These observations show chlorination of sunscreen active ingredients can dramatically decrease UV absorption and generate derivatives with altered biological properties.

Psychological Stress Alters Ultrastructure and Energy Metabolism of Masticatory Muscle in Rats

PubMed Central

Chen, Yong-Jin; Huang, Fei; Zhang, Min; Shang, Hai-Yan

2010-01-01

To investigate the effects of psychological stress on the masticatory muscles of rats, a communication box was applied to induce the psychological stress (PS) in rats. The successful establishment of psychological stimulation was confirmed by elevated serum levels of adrenocorticotropic hormone (ACTH) and changed behaviors in the elevated plusmaze apparatus. The energy metabolism of the bilateral masseter muscles was tested via chemocolorimetric analysis, whereas muscle ultrastructure was assessed by electron microscopy. In comparison to the control group, the PS group showed evidence of swollen mitochondria with cristae loss and reduced matrix density in the masticatory muscles after three weeks of stimulation; after five weeks of stimulation, severe vacuolar changes to the mitochondria were observed. Increased vascular permeability of the masticatory muscle capillaries was found in the five-week PS rats. In addition, there was decreased activity of Na+-K+ATPase and Ca2+-ATPase and a simultaneous increase in the activity of lactate dehydrogenase and lactic acid in the masticatory muscles of PS rats. Together, these results indicate that psychological stress induces alterations in the ultrastructure and energy metabolism of masticatory muscles in rats. PMID:21052548

Selective Cytotoxicity and Combined Effects of Camptothecin or Paclitaxel with Sodium-R-Alpha Lipoate on A549 Human Non-Small Cell Lung Cancer Cells

PubMed Central

Ibrahim, Sherif; Gao, Dayuan; Sinko, Patrick J.

2013-01-01

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and remains the deadliest form of cancer in the US and worldwide. New therapies are highly sought after to improve outcome. The effect of sodium-R-alpha lipoate on camptothecin- and paclitaxel-induced cytotoxicity was evaluated on A549 NSCLC and BEAS-2B ‘normal’ lung epithelial cells. Combination indices (CI) and dose reduction indices (DRI) were investigated by studying the cytotoxicity of sodium-R-alpha lipoate (0–16 mM), camptothecin (0–25 nM) and paclitaxel (0–0.06 nM) alone and in combination. 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium-bromide (MTT) was used to assess cytotoxicity. The combinational cytotoxic effects of sodium-R-alpha lipoate with camptothecin or paclitaxel were analyzed using a simulation of dose effects (CompuSyn®3.01). The effects of sodium-R-alpha lipoate on camptothecin- and paclitaxel-induced cytotoxicity varied based on concentrations and treatment times. It was found that sodium-R-alpha lipoate wasn’t cytotoxic towards BEAS-2B cells at any of the concentrations tested. For A549 cells, CIs [(additive (CI=1); synergistic (CI<1); antagonistic (CI>1)] were lower and DRIs were higher for the camptothecin/sodium-R-alpha-lipoate combination (CI=~0.17–1.5; DRI=~2.2–22.6) than the paclitaxel/sodium-R-alpha-lipoate combination (CI=~0.8–9.9; DRI=~0.10–5.8) suggesting that the camptothecin regimen was synergistic and that the addition of sodium-R-alpha lipoate was important for reducing the camptothecin dose and potential for adverse effects. PMID:24063429

IFNγ enhances cytotoxic efficiency of the cytotoxic T lymphocytes against human glioma cells.

PubMed

Shao, Shengwen; Risch, Eric; Burner, Danielle; Lu, Lingeng; Minev, Boris; Ma, Wenxue

2017-06-01

Cytotoxic T lymphocytes (CTLs) are a key player in cancer immunotherapies, and MHC class I molecules on the cell surface are crucial for cellular recognition. However, the aberrant expression of MHC class I molecules is frequently found in various malignancies. IFNγ has dual functions in cancer progression, and its effect on tumor immunity is controversial. To investigate whether IFNγ can enhance cytotoxic efficiency of the tumor antigen-specific CTLs, we generated the CTLs using modified human dendritic cells as antigen presenting cells, then studied the activities of CTLs on human leukocyte antigen (HLA)-A2 positive glioma cells treated with, or without IFNγ. The results from both ELISpot and cytotoxicity assays demonstrated that the CTLs recognized and eliminated the HLA-A2 positive glioma cells treated with IFNγ more effectively when compared to the glioma cells deprived of IFNγ treatment. In addition, in vitro experiments showed that the levels of MHC class I molecules were upregulated in all of the HLA-A2 positive glioma cells. Using the publicly accessed TCGA data of low-grade glioma, we found significantly positive associations between IFNγ and both MHC class I molecules and CD8 + T cell activation score (p<0.0001). Furthermore, we found a significantly reduced risk of death in the glioma patients with high T cell activation score in comparison to those with low score (p=0.022). These findings suggest that a clinical application of IFNγ treatment may have potential benefits. Copyright © 2017. Published by Elsevier B.V.

Silicon in Imperata cylindrica (L.) P. Beauv: content, distribution, and ultrastructure.

PubMed

Rufo, Lourdes; Franco, Alejandro; de la Fuente, Vicenta

2014-07-01

Silicon concentration, distribution, and ultrastructure of silicon deposits in the Poaceae Imperata cylindrica (L.) P. Beauv. have been studied. This grass, known for its medicinal uses and also for Fe hyperaccumulation and biomineralization capacities, showed a concentration of silicon of 13,705 ± 9,607 mg/kg dry weight. Silicon was found as an important constituent of cell walls of the epidermis of the whole plant. Silica deposits were found in silica bodies, endodermis, and different cells with silicon-collapsed lumen as bulliforms, cortical, and sclerenchyma cells. Transmission electron microscope observations of these deposits revealed an amorphous material of an ultrastructure similar to that previously reported in silica bodies of other Poaceae.

The cytotoxic effect of oxybuprocaine on human corneal epithelial cells by inducing cell cycle arrest and mitochondria-dependent apoptosis.

PubMed

Fan, W-Y; Wang, D-P; Wen, Q; Fan, T-J

2017-08-01

Oxybuprocaine (OBPC) is a widely used topical anesthetic in eye clinic, and prolonged and repeated usage of OBPC might be cytotoxic to the cornea, especially to the outmost corneal epithelium. In this study, we characterized the cytotoxic effect of OBPC on human corneal epithelial (HCEP) cells and investigated its possible cellular and molecular mechanisms using an in vitro model of non-transfected HCEP cells. Our results showed that OBPC at concentrations ranging from 0.025% to 0.4% had a dose- and time-dependent cytotoxicity to HCEP cells. Moreover, OBPC arrested the cells at S phase and induced apoptosis of these cells by inducing plasma membrane permeability, phosphatidylserine externalization, DNA fragmentation, and apoptotic body formation. Furthermore, OBPC could trigger the activation of caspase-2, -3, and -9, downregulate the expression of Bcl-xL, upregulate the expression of Bax along with the cytoplasmic amount of mitochondria-released apoptosis-inducing factor, and disrupt mitochondrial transmembrane potential. Our results suggest that OBPC has a dose- and time-dependent cytotoxicity to HCEP cells by inducing cell cycle arrest and cell apoptosis via a death receptor-mediated mitochondria-dependent proapoptotic pathway, and this novel finding provides new insights into the acute cytotoxicity and its toxic mechanisms of OBPC on HCEP cells.

Ultrastructural effects of pharmaceuticals (carbamazepine, clofibric acid, metoprolol, diclofenac) in rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio).

PubMed

Triebskorn, R; Casper, H; Scheil, V; Schwaiger, J

2007-02-01

In order to assess potential effects of human pharmaceuticals in aquatic wildlife, laboratory experiments were conducted with carbamazepine, clofibric acid, metoprolol, and diclofenac using fish as test organisms. For each substance, at least one environmentally relevant concentration was tested. In liver, kidney, and gills of trout and carp exposed to carbamazepine, clofibric acid, and metoprolol, ultrastructural effects were qualitatively described and semi-quantitatively assessed. The obtained assessment values were compared with previously published data for diclofenac-induced effects in rainbow trout tissues. Quantitative analyses of protein accumulated in kidneys of diclofenac-exposed trout corroborated previously published data which indicated that diclofenac induced a severe glomerulonephritis resulting in a hyaline droplet degeneration of proximal kidney tubules. The investigations provided information on the general health status of the pharmaceutical-exposed fish, and allowed a differential diagnosis of harmful effects caused by these human pharmaceuticals in non-target species. For the different cytological effects observed, lowest observed effect concentration (LOECs) for at least three of the test substances (diclofenac, carbamazepine, metoprolol) were in the range of environmentally relevant concentrations (1 microg/L).

Protective Effect of Prolactin against Methylmercury-Induced Mutagenicity and Cytotoxicity on Human Lymphocytes

PubMed Central

Silva-Pereira, Liz Carmem; da Rocha, Carlos Alberto Machado; Cunha, Luiz Raimundo Campos da Silva e; da Costa, Edmar Tavares; Guimarães, Ana Paula Araújo; Pontes, Thais Brilhante; Diniz, Domingos Luiz Wanderley Picanço; Leal, Mariana Ferreira; Moreira-Nunes, Caroline Aquino; Burbano, Rommel Rodríguez

2014-01-01

Mercury exhibits cytotoxic and mutagenic properties as a result of its effect on tubulin. This toxicity mechanism is related to the production of free radicals that can cause DNA damage. Methylmercury (MeHg) is one of the most toxic of the mercury compounds. It accumulates in the aquatic food chain, eventually reaching the human diet. Several studies have demonstrated that prolactin (PRL) may be differently affected by inorganic and organic mercury based on interference with various neurotransmitters involved in the regulation of PRL secretion. This study evaluated the cytoprotective effect of PRL on human lymphocytes exposed to MeHg in vitro, including observation of the kinetics of HL-60 cells (an acute myeloid leukemia lineage) treated with MeHg and PRL at different concentrations, with both treatments with the individual compounds and combined treatments. All treatments with MeHg produced a significant increase in the frequency of chromatid gaps, however, no significant difference was observed in the chromosomal breaks with any treatment. A dose-dependent increase in the mitotic index was observed for treatments with PRL, which also acts as a co-mitogenic factor, regulating proliferation by modulating the expression of genes that are essential for cell cycle progression and cytoskeleton organization. These properties contribute to the protective action of PRL against the cytotoxic and mutagenic effects of MeHg. PMID:25247425

Conventional and whitening toothpastes: cytotoxicity, genotoxicity and effect on the enamel surface.

PubMed

Camargo, Samira Esteves Afonso; Jóias, Renata Pilli; Santana-Melo, Gabriela Fátima; Ferreira, Lara Tolentino; El Achkar, Vivian Narana Ribeiro; Rode, Sigmar de Mello

2014-12-01

To evaluate the cytotoxicity and genotoxicity of whitening and common toothpastes, and the surface roughness of tooth enamel submitted to brushing with both toothpastes. Samples of whitening toothpastes [Colgate Whitening (CW) and Oral-B Whitening (OBW)] and regular (non-whitening) toothpastes (Colgate and Oral-B) were extracted in culture medium. Gingival human fibroblasts (FMM-1) were placed in contact with different dilutions of culture media that had been previously exposed to such materials, and the cytotoxicity was evaluated using the MTT assay. The genotoxicity was assessed by the micronucleus formation assay in Chinese hamster fibroblasts (V79). The cell survival rate and micronuclei number were assessed before and after exposure to the toothpaste extracts. For the surface roughness evaluation, 20 bovine tooth specimens, divided into four groups according to toothpastes, were submitted to 10,000 brushing cycles. The results were analyzed using the Mann-Whitney U and two-way ANOVA tests (P < 0.05). MTT assay showed that Colgate was significantly less cytotoxic than CW, Oral-B and OBW at all dilutions (P < 0.01). CW was the most cytotoxic toothpaste (P < 0.01). The whitening toothpastes showed the highest numbers of micronuclei compared to the untreated control (UC) (P < 0.01). Colgate and Oral-B toothpastes were not genotoxic compared to UC (P = 0.326). The OBW toothpaste was statistically significantly abrasive to the enamel surface (P < 0.01). The whitening toothpastes and Oral-B were cytotoxic to the cells. The whitening toothpastes were more genotoxic to cells in vitro than the common toothpastes, and genotoxicity was more pronounced in the OBW toothpaste.

The Effect of Early Intervention and Rehabilitation in the Expression of Aquaporin-4; and Ultrastructure Changes on Rat's Offspring's Damaged Brain Caused by Intrauterine Infection

PubMed Central

Rajesh, Kumar; Xiangying, Kong

2015-01-01

Objective To study the effect of early intervention and rehabilitation in the expression of aquaporin-4 and ultrastructure changes on cerebral palsy pups model induced by intrauterine infection. Methods 20 pregnant Wistar rats were consecutively injected with lipopolysaccharide intraperitoneally. 60 Pups born from lipopolysaccharide group were randomly divided into intervention group (n=30) and non-intervention group (n=30); intervention group further divided into early intervention and rehabilitation group (n=10), acupuncture group (n=10) and consolidate group (n=10). Another 5 pregnant rats were injected with normal saline intraperitoneally; 30 pups born from the normal saline group were taken as control group. The intervention group received early intervention, rehabilitation and acupuncture treatment. The motor functions of all pups were assessed via suspension test and modified BBB locomotor score. Aquaporin-4 expression in brain tissue was studied through immunohistochemical and western-blot analysis. Ultrastructure changes in damaged brain and control group were studied electron-microscopically. Results The scores of suspension test and modified BBB locomotor test were significantly higher in the control group than the intervention and non intervention group (p<0.01); higher in the intervention group than the non-intervention group (p<0.01). The expression of Aquaporin-4 was lower in intervention and non intervention group than in the control group (p<0.01); also lower in non-intervention group than the intervention group (p<0.01). Marked changes were observed in ultrastructure of cortex and hippocampus CAI in brain damaged group. Conclusion Early intervention and rehabilitation training can improve the motor function in offspring with brain injury and reduce the expression of aquaporin-4 in damaged brain. PMID:26279808

CYTOTOXICITY AND BIOCOMPATIBILITY OF DIRECT AND INDIRECT PULP CAPPING MATERIALS

PubMed Central

Modena, Karin Cristina da Silva; Casas-Apayco, Leslie Caroll; Atta, Maria Teresa; Costa, Carlos Alberto de Souza; Hebling, Josimeri; Sipert, Carla Renata; Navarro, Maria Fidela de Lima; Santos, Carlos Ferreira

2009-01-01

There are several studies about the cytotoxic effects of dental materials in contact with the pulp tissue, such as calcium hydroxide (CH), adhesive systems, resin composite and glass ionomer cements. The aim of this review article was to summarize and discuss the cytotoxicity and biocompatibility of materials used for protection of the dentin-pulp complex, some components of resin composites and adhesive systems when placed in direct or indirect contact with the pulp tissue. A large number of dental materials present cytotoxic effects when applied close or directly to the pulp, and the only material that seems to stimulate early pulp repair and dentin hard tissue barrier formation is CH. PMID:20027424

Intracellular origin and ultrastructure of platelet-derived microparticles.

PubMed

Ponomareva, A A; Nevzorova, T A; Mordakhanova, E R; Andrianova, I A; Rauova, L; Litvinov, R I; Weisel, J W

2017-08-01

Essentials Platelet microparticles play a major role in pathologies, including hemostasis and thrombosis. Platelet microparticles have been analyzed and classified based on their ultrastructure. The structure and intracellular origin of microparticles depend on the cell-activating stimulus. Thrombin-treated platelets fall apart and form microparticles that contain cellular organelles. Background Platelet-derived microparticles comprise the major population of circulating blood microparticles that play an important role in hemostasis and thrombosis. Despite numerous studies on the (patho)physiological roles of platelet-derived microparticles, mechanisms of their formation and structural details remain largely unknown. Objectives Here we studied the formation, ultrastructure and composition of platelet-derived microparticles from isolated human platelets, either quiescent or stimulated with one of the following activators: arachidonic acid, ADP, collagen, thrombin or calcium ionophore A23187. Methods Using flow cytometry, transmission and scanning electron microscopy, we analyzed the intracellular origin, structural diversity and size distributions of the subcellular particles released from platelets. Results The structure, dimensions and intracellular origin of microparticles depend on the cell-activating stimulus. The main structural groups include a vesicle surrounded by one thin membrane or multivesicular structures. Thrombin, unlike other stimuli, induced formation of microparticles not only from the platelet plasma membrane and cytoplasm but also from intracellular structures. A fraction of these vesicular particles having an intracellular origin contained organelles, such as mitochondria, glycogen granules and vacuoles. The size of platelet-derived microparticles depended on the nature of the cell-activating stimulus. Conclusion The results obtained provide a structural basis for the qualitative differences of various platelet activators, for specific

Cytotoxic effects of cuphiin D1 on the growth of human cervical carcinoma and normal cells.

PubMed

Wang, Ching-Chiung; Chen, Lih-Geeng; Yang, Ling-Ling

2002-01-01

Cuphiin D1 (CD1), macrocyclic hydrolyzable tannin isolated from Cuphea hyssopifolia, has been shown to exert an antitumor effect both in vitro and in vivo. Furthermore, CD1 significantly inhibited the growth of the human cervical carcinoma, i.e. HeLa, cells and showed less cytotoxicity to normal primary-cultured cervical fibroblasts. In this study, we explored the cytotoxic mechanism of CD1 on HeLa cells. The cytotoxic effects of CD1 showed dose-dependency at 3.15-100 micrograms/ml on HeLa for 12, 24, 48 and 72 hours and with an IC50 value at 14.2 micrograms/ml for 48 hours. However, the IC50 value of CD1 in primary-cultured normal cervical fibroblasts was 74.5 micrograms/ml. Therefore, the selectivity shown by CD1 is ascribed to differences in growth speeds between normal and tumor cells. HeLa cells treated with 50 micrograms/ml CD1 for 24 hours exhibited chromatin condensation, indicating the occurrence of apoptosis. Flow cytometric analysis demonstrated the presence of apoptotic cells with low DNA content among HeLa cells. CD1 also caused DNA fragmentation and inhibited Bcl-2, pro-caspase 3, and inactived PARP expression in HeLa cells. These results suggest that the inhibition of Bcl-2 expression in HeLa cells might account for the mechanism of CD1-induced apoptosis.

Cytotoxic Effects of Nonionic Iodinated Contrast Agent on Human Adipose-derived Mesenchymal Stem Cells.

PubMed

Wu, Tao; Nie, Hai; Dietz, Allan B; Salek, David R; Smith, Jay; van Wijnen, Andre J; Qu, Wenchun

2018-05-31

Transplantation of mesenchymal stem cells (MSCs) is a promising therapy for degenerative spine conditions. However, cell therapy for painful spine degeneration presently requires use of contrast agents during fluoroscopy-guided injections and the effects of these agents on MSCs represents a gap in knowledge. To investigate the biological effects of contrast media that are co-injected with MSCs. Prospective observational study. Academic medical center. Patient-derived clinical-grade culture expanded MSCs. Iohexol(Omnipaque300) was reduced to 12.5%, 25%, 50% and 100% of the stock solution and incubated with MSCs for 30 minutes, 4 hours and 48 hours. We also used complete media and 12.5%, 25%, 50%, 100% of phosphate buffered saline (PBS) as control group. We examined cytotoxicity of Iohexol at different concentrations and exposure duration, as well as the potential for recovery over time. Cell counts, mitochondrial activity, and quantitative real time reverse-transcriptase polymerase chain reaction (qRT-PCR) of related genes were analyzed immediately after exposure (day 0) and after two days of exposure (day 2). Human MSCs exhibit a time- and concentration-dependent cytotoxic response to iodinated CM. A brief 30min exposure did not affect MSCs function and viability. However, extended treatment with iohexol for 4 hours at 50% or higher concentration had a significant impact on both viability and gene expression in MSCs. CM (Omnipaque300) is cytotoxic to MSCs in a time-and concentration-dependent manner. Hence, the concentration of CM that accompanies MSC injections should be carefully considered during mesenchymal stem cell therapy for disc degenerative diseases. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Cytotoxic responses of selected insecticides in chick ganglia cultures.

PubMed Central

Sharma, R P; Obersteiner, E J

1981-01-01

Various agricultural chemicals, e.g. pesticides, are known to cause different toxic effects in man and animals. Some of these produce responses involving the nervous tissue. Total of 52 such chemicals, representing organophosphates, carbamates and other miscellaneous insecticides were evaluated to determine their relative cytotoxic effects in avian dorsal root ganglia cultures. Many of these chemicals caused a slight stimulation of cellular growth at very low concentrations. At toxic concentrations, a dose-related but nonspecific inhibition of cell growth occurred. The cytotoxic changes included the decreased migration of cells from the culture implant, varicosities in and shortening of various cells and vacuolization and rounding of neuroglial cells. At high concentrations, pigmentary degeneration and complete abolition of cell growth were observed. The toxic effects were numerically scored in a random blind fashion and the concentrations of individual chemicals to produce a half maximal effect (IC50) in culture were determined from the dose-response curves. The IC50 values for various chemicals ranged from approximately 10(-6) M for compounds like methylparathion, diazinon, paraoxon and Vendex to greater than 10(-2) M for chlorpyriphos and methylchlorpyriphos. No significant correlations of nerve fiber or glial cell cytotoxicity were apparent with other toxic or physico-chemical properties such as lethal dose in animals, cholinesterase inhibition, lipophilicity or water solubility of chemicals. Clinically neurotoxic and nonneurotoxic compounds caused similar cytotoxic effects in ganglia cultures. Images Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:7272842

First investigation of the collagen D-band ultrastructure in fossilized vertebrate integument

PubMed Central

Lingham-Soliar, Theagarten; Wesley-Smith, James

2008-01-01

The ultrastructure of dermal fibres of a 200 Myr thunniform ichthyosaur, Ichthyosaurus, specifically the 67 nm axial repeat D-banding of the fibrils, which characterizes collagen, is presented for the first time by means of scanning electron microscopy (SEM) analysis. The fragment of material investigated is part of previously described fossilized skin comprising an architecture of layers of oppositely oriented fibre bundles. The wider implication, as indicated by the extraordinary quality of preservation, is the robustness of the collagen molecule at the ultrastructural level, which presumably contributed to its survival during the initial processes of decomposition prior to mineralization. Investigation of the elemental composition of the sample by SEM–energy dispersive X-ray spectroscopy indicates that calcite and phosphate played important roles in the rapid mineralization and fine replication of the collagen fibres and fibrils. The exceedingly small sample used in the investigation and high level of information achieved indicate the potential for minimal damage to prized museum specimens; for example, ultrastructural investigations by SEM may be used to help resolve highly contentious questions, for example, ‘protofeathers’ in the Chinese dinosaurs. PMID:18577504

Antiplasmodial activities and cytotoxic effects of aqueous extracts and sesquiterpene lactones from Neurolaena lobata.

PubMed

François, G; Passreiter, C M; Woerdenbag, H J; Van Looveren, M

1996-04-01

Aqueous and lipophilic extracts of Neurolaena lobata (Asteraceae), obtained from Guatemala, were tested against Plasmodium falciparum in vitro. Moreover, sesquiterpene lactones, of the germacranolide and furanoheliangolide type, isolated from N. lobata, were shown to be active against P. falciparum in vitro. In addition to their antiplasmodial activity, their cytotoxic effects on human carcinoma cell lines were evaluated. Structure-activity relationships are discussed.

Mutagenic, cytotoxic, and teratogenic effects of 2-acetylaminofluorene and reactive metabolites in vitro.

PubMed

Faustman-Watts, E M; Yang, H Y; Namkung, M J; Greenaway, J C; Fantel, A G; Juchau, M R

1984-01-01

The embryotoxic, mutagenic, and cytotoxic properties of 2-acetylaminofluorene (AAF) and two of its reactive metabolites, N-acetoxy-2-acetylaminofluorene (AAAF) and 2-nitrosofluorene (NF) were assessed in vitro. A combined embryo culture/biotransformation system was used to determine the ability of these compounds to produce embryonic malformations, growth retardation, and/or embryolethality. Salmonella typhimurium auxotrophs (his-) were utilized to measure the mutagenic and cytotoxic potentials of these compounds. The parent compound, AAF, did not produce embryonic malformations or mutagenicity in the absence of an added cytochrome P-450-dependent monooxygenase system. Both metabolites produced each of the measured toxic effects without supplementation of a bioactivation system. However, the three chemicals each elicited a different spectrum of malformations. Bioactivated AAF produced neural tube abnormalities, whereas embryos treated with AAAF primarily exhibited prosencephalic malformations, and NF produced abnormalities of axial rotation or flexure. NF was approximately ten times more potent than AAAF as a direct-acting mutagen but only slightly more active in producing embryonic malformations in vitro. The results indicated that differential effects on the various measured parameters could be produced by these chemicals. The results indicated further that neither NF nor AAAF appeared to be individually responsible for the neural tube abnormalities generated by biotransformed AAF.

Effects of Cooking and In Vitro Digestion on Antioxidant Properties and Cytotoxicity of the Culinary-Medicinal Mushroom Pleurotus ostreatoroseus (Agaricomycetes).

PubMed

Brugnari, Tatiane; da Silva, Pedro Henrique Alves; Contato, Alex Graça; Inácio, Fabíola Dorneles; Nolli, Mariene Marques; Kato, Camila Gabriel; Peralta, Rosane Marina; de Souza, Cristina Giatti Marques

2018-01-01

In this study we evaluated the antioxidant capacity, antimicrobial activity, and cytotoxicity of an aqueous extract of the Pleurotus ostreatoroseus mushroom, which was cooked. Fresh basidiocarps were heated and steamed at 100°C and the resulting aqueous extract was assessed before and after in vitro digestion. Cooking reduced the amounts of phenolic compounds in the extract. The antioxidant activity of the extract was evaluated through the use of 4 methods. The lowest half-maximal effective concentration (EC50) against ABTS radicals was 0.057 ± 0.002 mg/mL for the uncooked basidiocarp extract. Cooking and the digestive process led to decreased activity (P > 0.05) against ABTS and DPPH radicals. A significant increase in chelating activity (P > 0.05) occurred after the basidiocarps were cooked (EC50 = 0.279 ± 0.007 mg/mL). The reducing power did not significantly change among the different extracts. The uncooked basidiocarp extract was cytotoxic to Vero cells. After cooking and subsequent in vitro digestion, the cytotoxicity of the extracts decreased (P < 0.05). Bacillus subtilis, Staphylococcus aureus, and Candida albicans were sensitive to the fresh mushroom extract. The data showed that after being cooked and digested, the P. ostreatoroseus mushroom maintains antioxidant activity and has a low cytotoxic effect.

[Effects of interferon-gamma on cytotoxicity of murine activated macrophages against murine glioma cells].

PubMed

Ohyama, K; Kikuchi, H; Oda, Y; Moritake, K; Yamasaki, T

1993-06-01

We studied the effects of mouse IFN-gamma on the cytotoxic activity of murine activated macrophages (M phi) against mouse VM-Glioma cells (H-2b). Activated M phi were obtained from peritoneal exudate cells of mice from four strains, C57BL/6 (H-2b), C3H/He(H-2k), DBA/2 (H-2d), and BALB/c (H-2d), following intraperitoneal injection of (1) LPS 200 micrograms, (2) BCG 200 micrograms, (3) C. parvum 200 micrograms, or (4) MDP 350 micrograms 7 days prior to 20-hr 51Cr release-assay. Of the various combination of mouse strains and activating agents tested, that of activated M phi of the C3H/He mouse with induction by LPS had the most tumoricidal effect against the glioma cells, which was not MHC restricted. Although LPS-activated M phi underwent marked loss of cytotoxicity following initiation of in vitro culture, this 24 hr pretreatment with IFN-gamma inhibited this reduction in tumoricidal effects in a dose-dependent fashion. On the other hand, 24 hr pretreatment of target cells with IFN-gamma did not increase their susceptibility to lysis by activated M phi. These findings suggest that IFN-gamma augments the in vitro tumoricidal activation of M phi; This effect appears to be unrelated to any influence of IFN-gamma on target sensitivity to lysis by macrophages.

Irritant and cytotoxic coumarins from Angelica glauca Edgew roots.

PubMed

Saeed, M Asif; Sabir, A W

2008-01-01

Irritant and cytotoxic potentiality of six coumarins, isolated for the first time from the roots of Angelica glauca identified as 5,6,7-trimethoxycoumarin, 6-methoxy-7,8-methylenedioxycoumarin, bergapten, decursinol angelate, decursin, and nodakenetin, were investigated. The irritant potential was explored by open mouse ear assay, evaluating their ID(50) after acute and by IU (Irritant units) after chronic effects, while the cytotoxic capability was explored by their LC(50), using brine shrimp (Artemia salina) larvae (nauplii). All the coumarins exhibited well-defined irritancy on mouse's ears, compared with the positive controlled euphorbium reaction and cytotoxic response against brine shrimp larvae, compared with the positive control colchicine. Decursinol angelate and decursin were the most potent and persistent irritant compounds with least ID(50), whose reactions lasted for 48 h. 6-Methoxy-7,8-methylenedioxycoumarin and bergaten revealed an intermediate irritant reactions, while 5,6,7-trimethoxycoumarin and nodakenetin displayed the least irritant and least persistent reactions on mouse ears. Both decursin and decursinol angelate also appeared to be the stronger cytotoxic agents than other coumarins. 5,6,7-trimethoxycoumarin displayed an intermediate cytotoxic behaviour, while other three coumarins, i.e., 6-methoxy-7,8-methylenedioxycoumarin, bergapten, and nodakenetin, exhibited the least cytotoxic capacity against brine shrimp larvae.

Effects of ionizing radiation on the enzyme activities and ultrastructural changes of poultry

NASA Astrophysics Data System (ADS)

Hwang, H.-I.; Hau, L.-B.

1995-02-01

Enzyme-catalyzed changes are generally recognized as one of the major reasons for fresh meat deterioration after irradiation. In this study, the effects of ionizing radiation and storage on the enzyme activities of poultry as well as the ultrastructural change of muscle were evaluated. When chicken breasts were irradiated at 4°C and -20°C, both Ca 2+-dependent protease and cathepsin D showed some degree of resistance to irradiation. The activities of those two enzymes decreased with the increase of irradiation doses. During storage, Ca 2+-dependent proteases showed a marked decrease in activity. On the other hand, the cathepsin D activity was not significantly changed at either 4°C or -20°C after 20 days. Transmission electron microscope examination showed no structural changes of the myofibrils with a radiation dose of up to 10 kGy at either 4°C or -20°C. Freezing protected the irradiated chicken breasts from autolytic enzymes damage during storage. In contrast, considerable sarcomere degradation occurred in Z-line for irradiated samples when stored at 4°C for 20 days. The action of the proteolytic enzymes may have been responsible for the sarcomere degradation in irradiated chicken breasts.

Ultrastructural Morphology of Sperm from Human Globozoospermia

PubMed Central

Ricci, Giuseppe; Andolfi, Laura; Luppi, Stefania; Boscolo, Rita; Zweyer, Marina; Trevisan, Elisa

2015-01-01

Globozoospermia is a rare disorder characterized by the presence of sperm with round head, lacking acrosome. Coiling tail around the nucleus has been reported since early human studies, but no specific significance has conferred it. By contrast, studies on animal models suggest that coiling tail around the nucleus could represent a crucial step of defective spermatogenesis, resulting in round-headed sperm. No observations, so far, support the transfer of this hypothesis to human globozoospermia. The purpose of this work was to compare ultrastructural morphology of human and mouse model globozoospermic sperm. Sperm have been investigated by using scanning and transmission electron microscopy. The images that we obtained show significant similarities to those described in GOPC knockout mice, an animal model of globozoospermia. By using this model as reference, we were able to identify the probable steps of the tail coiling process in human globozoospermia. Although we have no evidence that there is the same pathophysiology in man and knocked-out mouse, the similarities between these ultrastructural observations in human and those in the experimental model are very suggestive. This is the first demonstration of the existence of relevant morphological homologies between the tail coiling in animal model and human globozoospermia. PMID:26436098

Dermal Ultrastructure in Low Beighton Score Members of 17 Families with Hypermobile-Type Ehlers-Danlos Syndrome

PubMed Central

Hermanns-Lê, Trinh; Reginster, Marie-Annick; Piérard-Franchimont, Claudine; Delvenne, Philippe; Piérard, Gérald E.; Manicourt, Daniel

2012-01-01

The distinction between the Ehlers-Danlos syndrome hypermobile type (EDSH) and the benign joint hypermobility syndrome (BJHS) is unclear. The aim of the present study was to compare skin ultrastructural abnormalities of EDSH and BJHS among different families. Skin of 23 EDSH, 27 BJHS, and 41 asymptomatic subjects from 17 families was examined using transmission electron microscopy. Similar ultrastructural abnormalities were found irrespective of the Beighton score. Flower-like collagen fibrils represented the key change and elastic fibers were altered as well. Beighton score is a clinical parameter rating joint mobility that appeared unrelated to quantitative and qualitative collagen ultrastructural alterations in the skin. Some EDSH family members fit with BJHS diagnosis. BJHS possibly represents a mild variant of EDSH. PMID:23091361

Adenosine, but not guanosine, protects vaginal epithelial cells from Trichomonas vaginalis cytotoxicity.

PubMed

Menezes, Camila Braz; Frasson, Amanda Piccoli; Meirelles, Lucia Collares; Tasca, Tiana

2017-02-01

Trichomonas vaginalis causes the most common non-viral sexually transmitted disease worldwide. The cytoadherence and cytotoxicity upon the vaginal epithelial cells are crucial for the infection. Extracellular nucleotides are released during cell damage and, along with their nucleosides, can activate purinoceptors. The opposing effects of nucleotides versus nucleosides are regulated by ectonucleotidases. Herein we evaluated the hemolysis and cytolysis induced by T. vaginalis, as well as the extracellular nucleotide hydrolysis along with the effects mediated by nucleotides and nucleosides on cytotoxicity. In addition, the gene expression of purinoceptors in host cells was determined. The hemolysis and cytolysis exerted by all T. vaginalis isolates presented positive Pearson correlation. All T. vaginalis isolates were able to hydrolyze nucleotides, showing higher NTPDase than ecto-5'-nucleotidase activity. The most cytotoxic isolate, TV-LACM6, hydrolyzes ATP, GTP with more efficiency than AMP and GMP. The vaginal epithelial cell line (HMVII) expressed the genes for all subtypes of P1, P2X and P2Y receptors. Finally, when nucleotides and nucleosides were tested, the cytotoxic effect elicited by TV-LACM6 was increased with nucleotides. In contrast, the cytotoxicity was reversed by adenosine in presence of EHNA, but not by guanosine, contributing to the understanding of the purinergic signaling role on T. vaginalis cytotoxicity. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Deoxyarbutin Possesses a Potent Skin-Lightening Capacity with No Discernible Cytotoxicity against Melanosomes.

PubMed

Miao, Fang; Shi, Ying; Fan, Zhi-Feng; Jiang, Shan; Xu, Shi-Zheng; Lei, Tie-Chi

2016-01-01

Safe and effective ingredients capable of removing undesired hyperpigmentation from facial skin are urgently needed for both pharmaceutical and cosmetic purposes. Deoxyarbutin (4-[(tetrahydro-2H-pyran-2-yl) oxy] phenol, D-Arb) is a glucoside derivative of hydroquinone. Here, we investigated the toxicity and efficacy of D-Arb at the sub-cellular level (directly on melanosomes) and skin pigmentation using in vivo and in vitro models to compare with its parent compound hydroquinone (1,4-benzenediol, HQ). At first, we examined the ultrastructural changes of melanosomes in hyperpigmented guinea pig skin induced by 308-nm monochromatic excimer lightand/or treated with HQ and D-Arb using transmission electron microscopy. The results showed that prominent changes in the melanosomal membrane, such as bulb-like structure and even complete rupture of the outer membranes, were found in the skin after topical application of 5% HQ for 10 days. These changes were barely observed in the skin treated with D-Arb. To further clarify whether membrane toxicity of HQ was a direct result of the compound treatment, we also examinedultrastructural changes of individual melanosomes purified from MNT1 human melanoma cells. Similar observations were obtained from the naked melanosome model in vitro. Finally, we determined the effects of melanosomal fractions exposed to HQ or D-Arb on hydroxyl radical generation in the Fenton reaction utilizing an electron spin resonance assay. D-Arb-treated melanosomesexhibit a moderate hydroxyl radical-scavenging activity, whereas HQ-treated melanosomessignificantly generate more hydroxyl free radicals. This study suggests that D-Arb possesses a potent ability in skin lightening and antioxidation with less melanosome cytotoxicity.

Deoxyarbutin Possesses a Potent Skin-Lightening Capacity with No Discernible Cytotoxicity against Melanosomes

PubMed Central

Fan, Zhi-Feng; Jiang, Shan; Xu, Shi-Zheng; Lei, Tie-Chi

2016-01-01

Safe and effective ingredients capable of removing undesired hyperpigmentation from facial skin are urgently needed for both pharmaceutical and cosmetic purposes. Deoxyarbutin (4-[(tetrahydro-2H-pyran-2-yl) oxy] phenol, D-Arb) is a glucoside derivative of hydroquinone. Here, we investigated the toxicity and efficacy of D-Arb at the sub-cellular level (directly on melanosomes) and skin pigmentation using in vivo and in vitro models to compare with its parent compound hydroquinone (1,4-benzenediol, HQ). At first, we examined the ultrastructural changes of melanosomes in hyperpigmented guinea pig skin induced by 308-nm monochromatic excimer lightand/or treated with HQ and D-Arb using transmission electron microscopy. The results showed that prominent changes in the melanosomal membrane, such as bulb-like structure and even complete rupture of the outer membranes, were found in the skin after topical application of 5% HQ for 10 days. These changes were barely observed in the skin treated with D-Arb. To further clarify whether membrane toxicity of HQ was a direct result of the compound treatment, we also examinedultrastructural changes of individual melanosomes purified from MNT1 human melanoma cells. Similar observations were obtained from the naked melanosome model in vitro. Finally, we determined the effects of melanosomal fractions exposed to HQ or D-Arb on hydroxyl radical generation in the Fenton reaction utilizing an electron spin resonance assay. D-Arb-treated melanosomesexhibit a moderate hydroxyl radical-scavenging activity, whereas HQ-treated melanosomessignificantly generate more hydroxyl free radicals. This study suggests that D-Arb possesses a potent ability in skin lightening and antioxidation with less melanosome cytotoxicity. PMID:27776184

Protective effects of anethole dithiolethione against oxidative stress-induced cytotoxicity in human Jurkat T cells.

PubMed

Khanna, S; Sen, C K; Roy, S; Christen, M O; Packer, L

1998-07-01

The protective effects of anethole dithiolethione (ADT) against H2O2- or 4-hydroxynonenal (HNE)-induced cytotoxicity in human Jurkat T cells were investigated. Jurkat T cells were pretreated with ADT (10-50 microM) for 18 hr and then challenged with H202 or HNE for up to 4 hr. Cytotoxicity was assessed by measuring: 1) leakage of lactate dehydrogenase from cells to medium; and 2) exclusion of the DNA intercalating fluorescent probe propidium iodide by viable cells. Pretreatment of cells with ADT (10 or 25 microM) for 18 hr significantly protected cells against H202- or HNE-induced cytotoxicity. Treatment of cells with ADT (10-50 microM) for 72 hr significantly increased the activities of catalase and glutathione reductase. The maximum effect of ADT treatment on the activity of these enzymes was observed when cells were treated with 25 microM of ADT for 72 hr. A significant increase in cellular GSH was observed in cells that were treated with ADT for 72 hr. Using monobromobimane as a thiol probe, we consistently observed that cells pretreated for 18 hr with ADT (25 or 50 microM) had also increased total thiol content. Exposure of Jurkat T cells to H202 or HNE resulted in a time-dependent decrease in cellular GSH. ADT (10-50 microM, 18 hr) pretreatment circumvented H202-dependent lowering of cellular GSH. In conclusion, ADT proved to be a potent cytoprotective thiol antioxidant with multifaceted mechanisms of action, suggesting that the drug has a remarkable therapeutic potential.

Synergistic effects of ascorbate and sorafenib in hepatocellular carcinoma: New insights into ascorbate cytotoxicity

PubMed Central

Bisetto, Sara; Newberg, Andrew; Doria, Cataldo; Levine, Mark; Monti, Daniel A.; Hoek, Jan B.

2016-01-01

We investigated the mechanism of selective ascorbate-induced cytotoxicity in tumor cells, including Hep G2 cells, compared to primary hepatocytes. H2O2 formation was required for ascorbate cytotoxicity, as extracellular catalase treatment protected tumor cells. H2O2 generated by glucose oxidase treatment also caused cell killing, but treatment with a pharmacological dose (5-20 mM) of ascorbate was significantly more cytotoxic at comparable rates of H2O2 production, suggesting that ascorbate enhanced H2O2 cytotoxicity. This was further supported by the finding that ascorbate at a non-cytotoxic dose (1 mM) enhanced cell killing caused by glucose oxidase. Consistent with this conclusion, ascorbate treatment caused deregulation of cellular calcium homeostasis, resulting in massive mitochondrial calcium accumulation. Ascorbate acted synergistically with the chemotherapeutic sorafenib in killing Hep G2 cells, but not primary hepatocytes, suggesting adjuvant ascorbate treatment can broaden sorafenib's therapeutic range. Sorafenib caused mitochondrial depolarization and prevented mitochondrial calcium sequestration. Subsequent ascorbate addition further deregulated cellular calcium homeostasis promoting cell death. Additionally, we present the case of a patient with hepatocellular carcinoma (HCC) who had prolonged regression of a rib metastasis upon combination treatment with ascorbate and sorafenib, indicating that these studies have direct clinical relevance. PMID:27036367

Central granular cell odontogenic tumor: immunohistochemistry and ultrastructure.

PubMed

Meer, Shabnum; Altini, Mario; Coleman, Hedley; Daya, Nilesh

2004-01-01

Central granular cell odontogenic tumors are rare, with only 30 cases having been reported. The tumors usually occur in the mandibular molar area and are seen as localized painless swellings in patients older than 40 years. We report an additional case that occurred in the posterior mandible of an elderly black woman. All reported cases of this tumor are benign, and cure is effected by localized surgical excision. Ultrastructurally, the cells contain numerous lysosomes and phagocytic vacuoles. Immunohistochemically, the granular cells were positive for vimentin, CD68, muramidase, carcinogenic embryonic antigen, and bcl-2. These features support a mesenchymal origin with a possible histiocytic lineage for the granular cells. Awareness of the occurrence of this neoplasm is important to promote detection and differentiation from other intraoral granular cell lesions.

Antibacterial and Cytotoxic Activity of Compounds Isolated from Flourensia oolepis.

PubMed

Joray, Mariana Belén; Trucco, Lucas Daniel; González, María Laura; Napal, Georgina Natalia Díaz; Palacios, Sara María; Bocco, José Luis; Carpinella, María Cecilia

2015-01-01

The antibacterial and cytotoxic effects of metabolites isolated from an antibacterial extract of Flourensia oolepis were evaluated. Bioguided fractionation led to five flavonoids, identified as 2',4'-dihydroxychalcone (1), isoliquiritigenin (2), pinocembrin (3), 7-hydroxyflavanone (4), and 7,4'-dihydroxy-3'-methoxyflavanone (5). Compound 1 showed the highest antibacterial effect, with minimum inhibitory concentration (MIC) values ranging from 31 to 62 and 62 to 250 μg/mL, against Gram-positive and Gram-negative bacteria, respectively. On further assays, the cytotoxic effect of compounds 1-5 was determined by MTT assay on acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia (CML) cell lines including their multidrug resistant (MDR) phenotypes. Compound 1 induced a remarkable cytotoxic activity toward ALL cells (IC50 = 6.6-9.9 μM) and a lower effect against CML cells (IC50 = 27.5-30.0 μM). Flow cytometry was used to analyze cell cycle distribution and cell death by PI-labeled cells and by Annexin V/PI staining, respectively. Upon treatment, 1 induced cell cycle arrest in the G2/M phase accompanied by a strong induction of apoptosis. These results describe for the first time the antibacterial metabolites of F. oolepis extract, with 1 being the most effective. This chalcone also emerges as a selective cytotoxic agent against sensitive and resistant leukemic cells, highlighting its potential as a lead compound.

[Effect of low-intensity electromagnetic fields of industrial frequency on the ultrastructure and proliferative activity of rat's thymus cells].

PubMed

Zhitkevich, T I; Bokut', T B; Netukova, N I

2001-01-01

Effects of two types of low-intensity electromagnetic fields (EMF) of industrial frequency (50 Hz) on the fine structure and proliferative activity of thymic cells in white rats were studied. It was found that a weak EMF with a prevailing electrical component (380-480 V/m, 120-140 nT1) did not affect the DNA synthesis intensity. An EMF with a stronger magnetic induction (10-15 V/m, 800-1500 nT1) diminished the glucose-6-phosphate dehydrogenase activity and proliferative processes in cultured stimulated lymphocytes. Electron microscopic investigation of the thymus after both types of exposure revealed an accumulation of lymphocytes with pyknotic nuclei and electron-dense cytoplasm, as well as hypoplasia of the vascular endothelium. At the same time, EMF with a prevailing magnetic component produced a more marked negative effect on the ultrastructure of thymic cells, which indicated a lowered secretory activity of epitheliocytes.

The novel oral imatinib microemulsions: physical properties, cytotoxicity activities and improved Caco-2 cell permeability.

PubMed

Gundogdu, Evren; Karasulu, Hatice Yesim; Koksal, Cinel; Karasulu, Ercüment

2013-01-01

The objective of this study was to formulate imatinib (IM) loaded to water-in-oil (w/o) microemulsions as an alternative formulation for cancer therapy and to evaluate the cytotoxic effect of microemulsions Caco-2 and MCF-7. Moreover, permeability studies were also performed with Caco-2 cells. W/o microemulsion systems were developed by using pseudo-ternary phase diagram. According to cytotoxicity studies, all formulations did not exert a cytotoxic effect on Caco-2 cells. Furthermore, all formulations had a significant cytotoxic effect on MCF-7 cells and the cytotoxic effect of M3IM was significantly more than that of other microemulsions and IM solution (p < 0.05). The permeability studies of IM across Caco-2 cells showed that permeability value from apical to basolateral was higher than permeability value of other formulations. In conclusion, the microemulsion formulations as a drug carrier, especially M3IM formulation, may be used as an effective alternative breast cancer therapy for oral delivery of IM.

Ultrastructural and cytochemical evidence for single impulse initiation zones in vestibular macular nerve fibers of rat

NASA Technical Reports Server (NTRS)

Ross, Muriel D.; Chee, Oliver; Black, Samuel; Cutler, Lynn

1991-01-01

Cupric ion-ferricyanide labeling methods and related ferrocyanide-stained tissues were used to locate the characterize, at the ultrastructural level, presumptive impulse initiation zones in the three types of vestibular macular nerve fibers. Large-diameter, M-type vestibular nerve fibers terminate in a calyx at the heminode, and labeling is coextensive with the base of the calyx. Intermediate, M/U-type nerve fibers have short, unmyelinated preterminal segments that sometimes bifurcate intamacularly, and small-diameter, U-type nerve fibers have long, unmyelinated preterminal axons and up to three branches. Preterminals of these nerve fibers display ultrastructural heterogeneity that is correlated with labeling patterns for sodium channels and/or associated polyanionic sites. They have a nodelike ultrastructure and label heavily from near the heminode to the base of the macula. Their intramacular branches, less organized ultrastructurally, label only slightly. Results indicate that vestibular nerve fibers have one impulse initiation zone, located near the heminode, that varies in length according to nerve fiber type. Structural heterogeneity may favor impulse conduction in the central direction, and length of the impulse initiation zone could influence nerve discharge patterns.

Ultrastructural characteristics of some bacteria after treatment with Lubrol W.

PubMed

Cherepova, N; Spasova, D

1994-01-01

Specific ultrastructural changes occurred mainly in the cell wall and cytoplasmic membrane of Listeria monocytogenes, Salmonella typhimurium, Pseudomonas pseudomallei and Pseudomonas aeruginosa bacteria when treated with 0.5% and 1% Lubrol W1 by means of transmission and scanning electron microscopy.

The effects of particle size and surface coating on the cytotoxicity of nickel ferrite.

PubMed

Yin, H; Too, H P; Chow, G M

2005-10-01

The safety and toxicity of nanoparticles are of growing concern despite their significant scientific interests and promising potentials in many applications. The properties of nanoparticles depend not only on the size but also the structure, microstructure and surface coating. These in turn are controlled by the synthesis and processing conditions. The dependence of cytotoxicity on particle size and on the presence of oleic acid as surfactant on nickel ferrite particles were investigated in vitro using the Neuro-2A cell line as a model. For nickel ferrite particles without oleic acid prepared by ball milling, cytotoxicity was independent of particle size within the given mass concentrations and surface areas accessible to the cells. For nickel ferrite particles coated with oleic acid prepared by the polyol method, the cytotoxicity significantly increased when one or two layers of oleic acid were deposited. Large particles (150+/-50 nm diameter) showed a higher cytotoxicity than smaller particles (10+/-3 nm diameter).

Cymbopogon citratus essential oil: effect on polymicrobial caries-related biofilm with low cytotoxicity.

PubMed

Oliveira, Maria Alcionéia Carvalho de; Borges, Aline Chiodi; Brighenti, Fernanda Lourenção; Salvador, Marcos José; Gontijo, Aline Vidal Lacerda; Koga-Ito, Cristiane Yumi

2017-11-06

The objective of this study was to evaluate the effects of Cymbopogon citratus essential oil and its main compound (citral) against primary dental colonizers and caries-related species. Chemical characterization of the essential oil was performed by gas chromatography/mass spectroscopy (GC/MS), and the main compound was determined. Antimicrobial activity was tested against Actinomyces naeslundii, Lactobacillus acidophilus, S. gordonii, S. mitis, S. mutans, S. sanguinis and S. sobrinus. Minimum inhibitory and bactericide concentrations were determined by broth microdilution assay for streptococci and lactobacilli reference, and for clinical strains. The effect of the essential oil on bacterial adhesion and biofilm formation/disruption was investigated. Negative (without treatment) and positive controls (chlorhexidine) were used. The effect of citral on preformed biofilm was also tested using the same methodology. Monospecies and microcosm biofilms were tested. ANOVA or Kruskal-Wallis tests were used (α=0.05). Cytotoxicity of the essential oil to human keratinocytes was performed by MTT assay. GC/MS demonstrated one major component (citral). The essential oil showed an inhibitory effect on all tested bacterial species, including S. mutans and L. acidophilus. Essential oil of C. citratus (10X MIC) reduced the number of viable cells of lactobacilli and streptococci biofilms (p < 0.05). The essential oil inhibited adhesion of caries-related polymicrobial biofilm to dental enamel (p < 0.01). Citral significantly reduced the number of viable cells of streptococci biofilm (p < 0.001). The essential oil showed low cytotoxicity to human keratinocytes. Based on these findings, this study can contribute to the development of new formulations for products like mouthwash, against dental biofilms.

Study of Hydroquinone Mediated Cytotoxicity and Hypopigmentation Effects from UVB-Irradiated Arbutin and DeoxyArbutin

PubMed Central

Chang, Nai-Fang; Chen, Yi-Shyan; Lin, Ying-Ju; Tai, Ting-Hsuan; Chen, An-Ni; Huang, Chen-Hsuan; Lin, Chih-Chien

2017-01-01

Arbutin (Arb) and deoxyArbutin (dA) are both effective hypopigmentation agents. However, they are glucoside derivatives of hydroquinone (HQ), which may be decayed into HQ under higher energy environments. Therefore, safety and toxicity are very important issues when considering the usage of these compounds. However, no study has verified the properties of Ultra-Violet B (UVB)-irradiated Arb and dA. In this work, we investigated the cytotoxicity and hypopigmentation effects of UVB-irradiated Arb and dA in Detroit 551 human fibroblast cells and B16-F10 mouse melanoma cells. The results showed that UVB-irradiated Arb and dA have strong cytotoxicity for the fibroblast cells, especially for dA, the caspase-3 is also activated by the treatment of UVB-irradiated dA in Detroit 551 cells. The results correlated with the produced HQ. In addition, UVB-irradiated Arb and dA suppressed the production of melanin in melanoma cells; this is due to the release of HQ that compensates for the UVB triggered Arb and dA decomposition. PMID:28467382

Study of Hydroquinone Mediated Cytotoxicity and Hypopigmentation Effects from UVB-Irradiated Arbutin and DeoxyArbutin.

PubMed

Chang, Nai-Fang; Chen, Yi-Shyan; Lin, Ying-Ju; Tai, Ting-Hsuan; Chen, An-Ni; Huang, Chen-Hsuan; Lin, Chih-Chien

2017-05-03

Arbutin (Arb) and deoxyArbutin (dA) are both effective hypopigmentation agents. However, they are glucoside derivatives of hydroquinone (HQ), which may be decayed into HQ under higher energy environments. Therefore, safety and toxicity are very important issues when considering the usage of these compounds. However, no study has verified the properties of Ultra-Violet B (UVB)-irradiated Arb and dA. In this work, we investigated the cytotoxicity and hypopigmentation effects of UVB-irradiated Arb and dA in Detroit 551 human fibroblast cells and B16-F10 mouse melanoma cells. The results showed that UVB-irradiated Arb and dA have strong cytotoxicity for the fibroblast cells, especially for dA, the caspase-3 is also activated by the treatment of UVB-irradiated dA in Detroit 551 cells. The results correlated with the produced HQ. In addition, UVB-irradiated Arb and dA suppressed the production of melanin in melanoma cells; this is due to the release of HQ that compensates for the UVB triggered Arb and dA decomposition.

[The ultrastructure and activities of free radical scavenger in discolored gingiva adjacent to porcelain fused to metal crowns].

PubMed

Zhang, Zhong-ti; Yan, Lu; Zhong, Ming; Yang, Xiao-dong; Ai, Hong-jun

2007-04-01

This study was designed to study the discolored gingiva adjacent to porcelain fused to metal (PFM) crowns in terms of ultrastructure , SOD and GSH activities in 40 cases. The discolored gingival ultrastructures were observed and metal X-ray energy level was analyzed;The activities of SOD and GSH were measured and compared with normal control by student's t test and one-way ANOVA with SPSS10.0 software package. The discolored gingival ultrastructure had changes compared with the normal gingiva. Nickel and chromium were not found in the particles through X-ray energy machine within the discolored gingiva adjacent to PFM crown. The activities of SOD and GSH in discolored gingiva were significantly different from control(P<0.05) and the values at 6 to 18 months were significantly different from those at other times. The ultrastructure underwent changes in discolored gingiva after PFM restoration; the activity of SOD and GSH in discolored gingiva changed to result in apoptosis, and discoloration.

Hypertextual Ultrastructures: Movement and Containment in Texts and Hypertexts

ERIC Educational Resources Information Center

Coste, Rosemarie L.

2009-01-01

The surface-level experience of hypertextuality as formless and unbounded, blurring boundaries among texts and between readers and writers, is created by a deep structure which is not normally presented to readers and which, like the ultrastructure of living cells, defines and controls texts' nature and functions. Most readers, restricted to…

Pancreatic PEComa: a case report with ultrastructural localization of HMB-45 within melanosomes.

PubMed

Finzi, Giovanna; Micello, Donata; Wizemann, Giorgio; Sessa, Fausto; Capella, Carlo

2012-04-01

PEComas (perivascular epithelioid cell tumors) represent a group of mesenchymal neoplasms showing characteristic morphologic, immunohistochemical, ultrastructural, and genetic features. These neoplasms are usually considered benign, being often well circumscribed by a thin capsule and showing scarce atypia. However, in some cases, they show local invasion and multiple metastases and cause the patient's death. PEComas have been found in many locations, but only 7 cases have been described in the pancreas to date. Here, the authors report an additional case of this rare neoplasm and demonstrate the HMB-45 immunoreactivity of melanosomes or premelanosomes at the ultrastructural level.

Ultrastructure of the root cap of Arabidopsis Thaliana L. Heynh under spaceflight conditions

NASA Technical Reports Server (NTRS)

1983-01-01

Peculiarities of the ultrastructural organization of Arabidopsis root cap cells grown from the stage of two cotyledonous leaves in the Svetoblok-1 apparatus aboard the Salyut 6 research orbital station and in the laboratory are assessed. It is established that under conditions of real space flight vacuolization of the root cap cells increses considerably compared to the control variant. Changes in the topography and ulstrastructure of amyloplasts as well as lysis of cell walls are observed in the material under study. An assumption is advanced on analogous cell responses observed at the ultrastructural level to weightlessness and clinostatic conditions.

A cytotoxicity assay for Clostridium spiroforme enterotoxin in cecal fluid of rabbits.

PubMed

Butt, M T; Papendick, R E; Carbone, L G; Quimby, F W

1994-02-01

Clostridium spiroforme enterotoxin-mediated diarrhea can be a common cause of mortality among weanling age rabbits. Definitive diagnosis of this disorder requires detection of the causative enterotoxin. Using filtered cecal supernatant from necropsy specimens, antibodies to C. spiroforme and its products and Vero cells, a cytotoxicity assay was performed on 22 rabbits with clinical signs and lesions consistent with C. spiroforme enterotoxin-mediated diarrhea. A cytotoxic effect was detected, generally within 4 h, in 18 of 22 rabbits. The cytotoxic effect was blocked by preincubation of the cecal material with antibodies to C. spiroforme and its products. Culture of cecal contents and smears of cecal contents identified C. spiroforme in 10/22 and 12/22 cases, respectively. This cytotoxicity assay provided a rapid and sensitive method for diagnosing C. spiroforme enterotoxin-mediated diarrhea.

Generation of a three-dimensional ultrastructural model of human respiratory cilia.

PubMed

Burgoyne, Thomas; Dixon, Mellisa; Luther, Pradeep; Hogg, Claire; Shoemark, Amelia

2012-12-01

The ultrastructures of cilia and flagella are highly similar and well conserved through evolution. Consequently, Chlamydomonas is commonly used as a model organism for the study of human respiratory cilia. Since detailed models of Chlamydomonas axonemes were generated using cryoelectron tomography, disparities among some of the ultrastructural features have become apparent when compared with human cilia. Extrapolating information on human disease from the Chlamydomonas model may lead to discrepancies in translational research. This study aimed to establish the first three-dimensional ultrastructural model of human cilia. Tomograms of transverse sections (n = 6) and longitudinal sections (n = 9) of human nasal respiratory cilia were generated from three healthy volunteers. Key features of the cilium were resolved using subatomic averaging, and were measured. For validation of the method, a model of the well characterized structure of Chlamydomonas reinhardtii was simultaneously generated. Data were combined to create a fully quantified three-dimensional reconstruction of human nasal respiratory cilia. We highlight key differences in the axonemal sheath, microtubular doublets, radial spokes, and dynein arms between the two structures. We show a decreased axial periodicity of the radial spokes, inner dynein arms, and central pair protrusions in the human model. We propose that this first human model will provide a basis for research into the function and structure of human respiratory cilia in health and in disease.

General Characteristics and Cytotoxic Effects of Nano-Poly (Butyl Cyanoacrylate) Containing Carboplatin on Ovarian Cancer Cells

PubMed Central

Kanaani, Leila; Far, Meysam Ebrahimi; Kazemi, S Maryam; Choupani, Edris; Tabrizi, Maral Mazloumi; Shahmabadi, Hasan Ebrahimi; Khiyavi, Azim Akbarzadeh

2017-01-01

The initial response to treatment and subsequent development of resistance to carboplatin are very important challenges. Use of nano drug delivery is a new method to replace standard chemotherapy. In this research, both non-PEGylated and PEGylated nanoparticles (NPs) were prepared by mini-emulsion polymerization of poly (butyl cyanoacrylate) (PBCA) NPs. Characteristics such as size, polydispersity index (PDI), zeta potential, drug release, and stability were examined. In addition, infrared spectroscopy was used for description of the produced NPs. Then, cytotoxicity effects of both formulations were studied on the A2780CIS ovarian cancer cell line with incubation for 24, 48, and 72h. Examination of characteristics of loaded carboplatin on the PBCA NPs under suitable laboratory conditions showed a positive effect of PEG on their properties. Cytotoxicity studies demonstrated greater toxicity with both formulations of nano-drugs than the free drug. The results indicated that PBCA NPs can be considered as suitable candidates for nano-drugs in chemotherapy. PMID:28240014

Cytotoxic and phytotoxic actions of Heliotropium strigosum.

PubMed

Shah, Syed Majid; Hussain, Sajid; Khan, Arif-Ullah; Shah, Azhar-Ul-Haq Ali; Khan, Haroon; Ullah, Farhat; Barkatullah

2015-05-01

This study describes the cytotoxic and phytotoxic activities of the crude extract of Heliotropium strigosum and its resultant fractions. In brine shrimp toxicology assays, profound cytotoxicity was displayed by ethyl acetate (LD50 8.3 μg/ml) and chloroform (LD50 8.8 μg/ml) fractions, followed by relatively weak crude methanolic extract of H. strigosum (LD50 909 μg/ml) and n-hexane fraction (LD50 1000 μg/ml). In case of phytotoxicity activity against Lemna acquinoctialis, highest phytotoxic effect was showed by ethyl acetate fraction (LD50 91.0 μg/ml), while chloroform fraction, plant crude extract and n-hexane, respectively, caused 50%, 30.76 ± 1.1% and 30.7 ± 1.1% inhibitory action at maximum concentration used, that is, 1000 μg/ml. These data indicates that H. strigosum exhibits cytotoxic and phytotoxic potential, which explore its use as anticancer and herbicidal medicine. The ethyl acetate and chloroform fractions were more potent for the evaluated toxicity effects, thus recommended for isolation and identification of the active compounds. © The Author(s) 2012.

Cytotoxic and genotoxic studies of essential oil from Rosa damascene Mill., Kashan, Iran.

PubMed

Shokrzadeh, Mohammad; Habibi, Emran; Modanloo, Mona

2017-08-01

Aim Rosa damascene Mill. belongs to the family of Roseaceae and its essential oil is produced in large amounts in Iran. The wide application of rose oil has raised questions about potential adverse health effects. We have investigated cytotoxic activity and genotoxic effects of Rosa oil from Kashan, Iran. Methods The cytotoxic effect and IC50 of the essential oil on the cell lines was studied followed by MTT assay. In this assay mitochondrial oxidoreductase enzymes with reducing the tetrazolium dye MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) reflect the number of viable cells. Genotoxic effect of the oil was evaluated by micronucleus assay by evaluating produced micronuclei due to cytogenetic damage in binucleated lymphocytes. Results The results showed that essential oil significantly had cytotoxic and genotoxic effects at doses over 10µg/mL (p<0.05). Also, essential oil of Rose showed lower IC50 in cancer cell line (A549) in comparison with the normal cell line (NIH3T3). Conclusion Cytotoxic and genotoxic properties of essential oil of Rose in Kashan, Iran, are safe at a dose of 10µg/mL. Also, a good cytotoxic effect was shown and could be introduced as an anticancer compound. Further studies are needed with regard to anti-cancer effects of Rose essential oil. Copyright© by the Medical Assotiation of Zenica-Doboj Canton.

Clinical Features of Childhood Primary Ciliary Dyskinesia by Genotype and Ultrastructural Phenotype

PubMed Central

Ferkol, Thomas W.; Rosenfeld, Margaret; Lee, Hye-Seung; Dell, Sharon D.; Sagel, Scott D.; Milla, Carlos; Zariwala, Maimoona A.; Pittman, Jessica E.; Shapiro, Adam J.; Carson, Johnny L.; Krischer, Jeffrey P.; Hazucha, Milan J.; Cooper, Matthew L.; Knowles, Michael R.; Leigh, Margaret W.

2015-01-01

Rationale: The relationship between clinical phenotype of childhood primary ciliary dyskinesia (PCD) and ultrastructural defects and genotype is poorly defined. Objectives: To delineate clinical features of childhood PCD and their associations with ultrastructural defects and genotype. Methods: A total of 118 participants younger than 19 years old with PCD were evaluated prospectively at six centers in North America using standardized procedures for diagnostic testing, spirometry, chest computed tomography, respiratory cultures, and clinical phenotyping. Measurements and Main Results: Clinical features included neonatal respiratory distress (82%), chronic cough (99%), and chronic nasal congestion (97%). There were no differences in clinical features or respiratory pathogens in subjects with outer dynein arm (ODA) defects (ODA alone; n = 54) and ODA plus inner dynein arm (IDA) defects (ODA + IDA; n = 18) versus subjects with IDA and central apparatus defects with microtubular disorganization (IDA/CA/MTD; n = 40). Median FEV1 was worse in the IDA/CA/MTD group (72% predicted) versus the combined ODA groups (92% predicted; P = 0.003). Median body mass index was lower in the IDA/CA/MTD group (46th percentile) versus the ODA groups (70th percentile; P = 0.003). For all 118 subjects, median number of lobes with bronchiectasis was three and alveolar consolidation was two. However, the 5- to 11-year-old IDA/CA/MTD group had more lobes of bronchiectasis (median, 5; P = 0.0008) and consolidation (median, 3; P = 0.0001) compared with the ODA groups (median, 3 and 2, respectively). Similar findings were observed when limited to participants with biallelic mutations. Conclusions: Lung disease was heterogeneous across all ultrastructural and genotype groups, but worse in those with IDA/CA/MTD ultrastructural defects, most of whom had biallelic mutations in CCDC39 or CCDC40. PMID:25493340

Lactobacillus delbrueckii ssp. bulgaricus B-30892 can inhibit cytotoxic effects and adhesion of pathogenic Clostridium difficile to Caco-2 cells

PubMed Central

Banerjee, Pratik; Merkel, Glenn J; Bhunia, Arun K

2009-01-01

Background Probiotic microorganisms are receiving increasing interest for use in the prevention, treatment, or dietary management of certain diseases, including antibiotic-associated diarrhea (AAD). Clostridium difficile is the most common cause of AAD and the resulting C. difficile – mediated infection (CDI), is potentially deadly. C. difficile associated diarrhea (CDAD) is manifested by severe inflammation and colitis, mostly due to the release of two exotoxins by C. difficile causing destruction of epithelial cells in the intestine. The aim of this study was to determine the effect of probiotic bacteria Lactobacillus delbrueckii ssp. bulgaricus B-30892 (LDB B-30892) on C. difficile-mediated cytotoxicity using Caco-2 cells as a model. Methods Experiments were carried out to test if the cytotoxicity induced by C. difficile-conditioned-medium on Caco-2 cells can be altered by cell-free supernatant (CFS) from LDB B-30892 in different dilutions (1:2 to 1:2048). In a similar experimental setup, comparative evaluations of other probiotic strains were made by contrasting the results from these strains with the results from LDB B-30892, specifically the ability to affect C. difficile induced cytotoxicity on Caco-2 monolayers. Adhesion assays followed by quantitative analysis by Giemsa staining were conducted to test if the CFSs from LDB B-30892 and other probiotic test strains have the capability to alter the adhesion of C. difficile to the Caco-2 monolayer. Experiments were also performed to evaluate if LDB B-30892 or its released components have any bactericidal effect on C. difficile. Results and discussion Co-culturing of LDB B-30892 with C. difficile inhibited the C. difficile-mediated cytotoxicity on Caco-2 cells. When CFS from LDB B-30892-C. difficile co-culture was administered (up to a dilution of 1:16) on Caco-2 monolayer, there were no signs of cytotoxicity. When CFS from separately grown LDB B-30892 was mixed with the cell-free toxin preparation (CFT) of

Kinetics and pathogenesis of intracellular magnetic nanoparticle cytotoxicity

NASA Astrophysics Data System (ADS)

Giustini, Andrew J.; Gottesman, Rachel E.; Petryk, A. A.; Rauwerdink, A. M.; Hoopes, P. Jack

2011-03-01

Magnetic nanoparticles excited by alternating magnetic fields (AMF) have demonstrated effective tumor-specific hyperthermia. This treatment is effective as a monotherapy as well as a therapeutic adjuvant to chemotherapy and radiation. Iron oxide nanoparticles have been shown, so far, to be non-toxic, as are the exciting AMF fields when used at moderate levels. Although higher levels of AMF can be more effective, depending on the type of iron oxide nanoparticles use, these higher field strengths and/or frequencies can induce normal tissue heating and toxicity. Thus, the use of nanoparticles exhibiting significant heating at low AMF strengths and frequencies is desirable. Our preliminary experiments have shown that the aggregation of magnetic nanoparticles within tumor cells improves their heating effect and cytotoxicity per nanoparticle. We have used transmission electron microscopy to track the endocytosis of nanoparticles into tumor cells (both breast adenocarcinoma (MTG-B) and acute monocytic leukemia (THP-1) cells). Our preliminary results suggest that nanoparticles internalized into tumor cells demonstrate greater cytotoxicity when excited with AMF than an equivalent heat dose from excited external nanoparticles or cells exposed to a hot water bath. We have also demonstrated that this increase in SAR caused by aggregation improves the cytotoxicity of nanoparticle hyperthermia therapy in vitro.

Dietary adaptions in the ultrastructure of dinosaur dentine.

PubMed

Brink, Kirstin S; Chen, Yu-Cheng; Wu, Ya-Na; Liu, Wei-Min; Shieh, Dar-Bin; Huang, Timothy D; Sun, Chi-Kuang; Reisz, Robert R

2016-12-01

Teeth are key to understanding the feeding ecology of both extant and extinct vertebrates. Recent studies have highlighted the previously unrecognized complexity of dinosaur dentitions and how specific tooth tissues and tooth shapes differ between taxa with different diets. However, it is unknown how the ultrastructure of these tooth tissues contributes to the differences in feeding style between taxa. In this study, we use third harmonic generation microscopy and scanning electron microscopy to examine the ultrastructure of the dentine in herbivorous and carnivorous dinosaurs to understand how the structure of this tissue contributes to the overall utility of the tooth. Morphometric analyses of dentinal tubule diameter, density and branching rates reveal a strong signal for dietary preferences, with herbivorous saurischian and ornithischian dinosaurs consistently having higher dentinal tubule density than their carnivorous relatives. We hypothesize that this relates to the hardness of the dentine, where herbivorous taxa have dentine that is more resistant to breakage and wear at the dentine-enamel junction than carnivorous taxa. This study advocates the detailed study of dentine and the use of advanced microscopy techniques to understand the evolution of dentition and feeding ecology in extinct vertebrates. © 2016 The Author(s).

Cold-induced ultrastructural changes in bull and boar sperm plasma membranes.

PubMed

De Leeuw, F E; Chen, H C; Colenbrander, B; Verkleij, A J

1990-04-01

The effect of low temperatures on the ultrastructure of the plasma membrane of bull and boar spermatozoa was investigated. Cold-induced changes in the organization of sperm plasma membrane components were demonstrated by the use of fast-freezing combined with freeze-fracture electron microscopy. This preparation technique ensures fixation without artifacts. At 38 degrees C bull and boar spermatozoa exhibited a random distribution of intramembranous particles over the plasma membrane of both head and tail. Exposure to 0 degree C resulted in redistribution of the intramembranous particles: on the head and principal piece of bull spermatozoa and on the principal piece of boar spermatozoa, particle-free areas were observed, whereas on the boar sperm head, particle aggregates were present. The original particle distribution was restored upon rewarming of bull and boar spermatozoa to 38 degrees C, as well as after freezing and thawing of bull spermatozoa. Dilution of bull and boar semen into Tris-dilution buffer and Beltsville Thaw Solution-dilution buffer, respectively, could not prevent cold-induced redistribution of intramembranous particles. The observed particle reorganization upon cooling was interpreted as the result of lateral phase separation in the plasma membrane. Species-dependent differences in cold-induced ultrastructural changes were considered to be determined by lipid composition and asymmetry of the plasma membrane, and might be related to differences in cold resistance between species.

Synthesis, X-ray structure and cytotoxic effect of nickel(II) complexes with pyrazole ligands.

PubMed

Sobiesiak, Marta; Lorenz, Ingo-Peter; Mayer, Peter; Woźniczka, Magdalena; Kufelnicki, Aleksander; Krajewska, Urszula; Rozalski, Marek; Budzisz, Elzbieta

2011-12-01

Here we present the synthesis of the new Ni(II) complexes with chelating ligands 1-benzothiazol-2-yl-3,5-dimethyl-1H-pyrazole (a), 5-(2-hydroxyphenyl)-3-methyl-1-(2-pyridylo)-1H-pyrazole-4-carboxylic acid methyl ester (b) and 1-benzothiazol-2-yl-5-(2-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carboxylic acid methyl ester (c). These ligands a-c create solid complexes with Ni(II). The crystal and molecular structures of two complexes were determined by X-ray diffraction method. Thermal stability of two complexes with ligand c by TG/DTG and DSC methods were also shown. Cytotoxic activity of all the complexes against three tumour cell lines and to normal endothelial cells (HUVEC) was also estimated. Complexes with ligand c exhibited relatively high cytotoxic activity towards HL-60 and NALM-6 leukaemia cells and WM-115 melanoma cells. Cytotoxic effectiveness of one of these complexes against melanoma WM-115 cells was two times higher than that of cisplatin. The protonation constant log K=9.63 of ligand b corresponding to the phenol 2-hydroxy group has been determined in 10% (v/v) DMSO/water solution (25°C). The coordination modes (formation of two monomeric species: NiL and NiL(2)) in the complexes with Ni(II) are discussed for b on the basis of the potentiometric and UV/Vis data. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Genotoxicity and Cytotoxicity Evaluation of the Neolignan Analogue 2-(4-Nitrophenoxy)-1Phenylethanone and its Protective Effect Against DNA Damage

PubMed Central

Hanusch, Alex Lucas; de Oliveira, Guilherme Roberto; de Sabóia-Morais, Simone Maria Teixeira; Machado, Rafael Cosme; dos Anjos, Murilo Machado; Chen Chen, Lee

2015-01-01

Neolignans are secondary metabolites found in various groups of Angiosperms. They belong to a class of natural compounds with great diversity of chemical structures and pharmacological activities. These compounds are formed by linking two phenylpropanoid units. Several compounds that have ability to prevent genetic damage have been isolated from plants, and can be used to prevent or delay the development of tumor cells. Genetic toxicology evaluation is widely used in risk assessment of new drugs in preclinical screening tests. In this study, we evaluated the genotoxicity and cytotoxicity of the neolignan analogue 2-(4-nitrophenoxy)-1-phenylethanone (4NF) and its protective effect against DNA damage using the mouse bone marrow micronucleus test and the comet assay in mouse peripheral blood. Our results showed that this neolignan analogue had no genotoxic activity and was able to reduce induced damage both in mouse bone marrow and peripheral blood. Although the neolignan analogue 4NF was cytotoxic, it reduced cyclophosphamide-induced cytotoxicity. In conclusion, it showed no genotoxic action, but exhibited cytotoxic, antigenotoxic, and anticytotoxic activities. PMID:26554835

Synergistic effects of ascorbate and sorafenib in hepatocellular carcinoma: New insights into ascorbate cytotoxicity.

PubMed

Rouleau, Lauren; Antony, Anil Noronha; Bisetto, Sara; Newberg, Andrew; Doria, Cataldo; Levine, Mark; Monti, Daniel A; Hoek, Jan B

2016-06-01

We investigated the mechanism of selective ascorbate-induced cytotoxicity in tumor cells, including Hep G2 cells, compared to primary hepatocytes. H2O2 formation was required for ascorbate cytotoxicity, as extracellular catalase treatment protected tumor cells. H2O2 generated by glucose oxidase treatment also caused cell killing, but treatment with a pharmacologic dose (5-20mM) of ascorbate was significantly more cytotoxic at comparable rates of H2O2 production, suggesting that ascorbate enhanced H2O2 cytotoxicity. This was further supported by the finding that ascorbate at a non-cytotoxic dose (1mM) enhanced cell killing caused by glucose oxidase. Consistent with this conclusion, ascorbate treatment caused deregulation of cellular calcium homeostasis, resulting in massive mitochondrial calcium accumulation. Ascorbate acted synergistically with the chemotherapeutic sorafenib in killing Hep G2 cells, but not primary hepatocytes, suggesting adjuvant ascorbate treatment can broaden sorafenib's therapeutic range. Sorafenib caused mitochondrial depolarization and prevented mitochondrial calcium sequestration. Subsequent ascorbate addition further deregulated cellular calcium homeostasis promoting cell death. Additionally, we present the case of a patient with hepatocellular carcinoma (HCC) who had prolonged regression of a rib metastasis upon combination treatment with ascorbate and sorafenib, indicating that these studies have direct clinical relevance. Copyright © 2016 Elsevier Inc. All rights reserved.

Cystatin F Affects Natural Killer Cell Cytotoxicity

PubMed Central

Perišić Nanut, Milica; Sabotič, Jerica; Švajger, Urban; Jewett, Anahid; Kos, Janko

2017-01-01

Cystatin F is a cysteine peptidase inhibitor which, unlike other cystatin family members, is targeted to endosomal/lysosomal compartments. It is synthesized as an inactive disulfide-linked dimer which is then converted to an active monomer by proteolytic cleavage of 15 N-terminal residues. Cystatin F has been suggested to regulate the cytotoxicity of natural killer (NK) cells by inhibiting the major granzyme convertases, cathepsins C and H. To test this hypothesis, we prepared variants of cystatin F and analyzed their uptake, subcellular trafficking, and peptidase inhibition, as well as their impact on the cytotoxicity of NK-92 cells and primary NK cells. The N-glycosylation pattern is responsible for the secretion, uptake, and subcellular sorting of cystatin F in HeLa and Hek293 cells, whereas the legumain binding site had no effect on these processes. Active, N-terminally truncated, monomeric cystatin F can also be internalized by recipient cells and targeted to endo/lysosomes, affecting also cells lacking the activating peptidase. Cystatin F mutants capable of cell internalization and trafficking through the endo/lysosomal pathway significantly decreased cathepsin C and H activities, both in situ, following transfection and in trans, using conditioned media. Further, incubation of IL-2 stimulated NK-92 and primary NK cells with full-length and N-terminally truncated cystatin F mutants led to suppression of their granule-mediated cytotoxicity. This effect was most significant with the N-terminally truncated mutants. These results suggest that cystatin F can be an important mediator within tumor microenvironment affecting the cytotoxicity of NK cells and consequently antitumor immune response. PMID:29180998

Quantitative Assessment of Ultrastructure and Light Scatter in Mouse Corneal Debridement Wounds

PubMed Central

Boote, Craig; Du, Yiqin; Morgan, Sian; Harris, Jonathan; Kamma-Lorger, Christina S.; Hayes, Sally; Lathrop, Kira L.; Roh, Danny S.; Burrow, Michael K.; Hiller, Jennifer; Terrill, Nicholas J.; Funderburgh, James L.; Meek, Keith M.

2012-01-01

Purpose. The mouse has become an important wound healing model with which to study corneal fibrosis, a frequent complication of refractive surgery. The aim of the current study was to quantify changes in stromal ultrastructure and light scatter that characterize fibrosis in mouse corneal debridement wounds. Methods. Epithelial debridement wounds, with and without removal of basement membrane, were produced in C57BL/6 mice. Corneal opacity was measured using optical coherence tomography, and collagen diameter and matrix order were quantified by x-ray scattering. Electron microscopy was used to visualize proteoglycans. Quantitative PCR (Q-PCR) measured mRNA transcript levels for several quiescent and fibrotic markers. Results. Epithelial debridement without basement membrane disruption produced a significant increase in matrix disorder at 8 weeks, but minimal corneal opacity. In contrast, basement membrane penetration led to increases in light scatter, matrix disorder, and collagen diameter, accompanied by the appearance of abnormally large proteoglycans in the subepithelial stroma. This group also demonstrated upregulation of several quiescent and fibrotic markers 2 to 4 weeks after wounding. Conclusions. Fibrotic corneal wound healing in mice involves extensive changes to collagen and proteoglycan ultrastructure, consistent with deposition of opaque scar tissue. Epithelial basement membrane penetration is a deciding factor determining the degree of ultrastructural changes and resulting opacity. PMID:22467580

Glutathione reduces cytotoxicity of polyethyleneimine coated magnetic nanoparticles in CHO cells.

PubMed

Strojan, Klemen; Lojk, Jasna; Bregar, Vladimir B; Veranič, Peter; Pavlin, Mojca

2017-06-01

Polyethyleneimine (PEI) is a polycationic compound frequently used as a transfection agent. However, cytotoxicity of PEI and PEI-coated nanoparticles (PEI NPs) is still a major obstacle in its use. In this study we report a method for reducing cytotoxicity of PEI NPs by addition of glutathione in NPs synthesis. Glutathione reduced cytotoxic effects for at least 30% and decreased observed oxidative stress response compared to standard formulation. Results showed that the effect was partially due to reduced zeta potential and partially due to protective antioxidant properties of glutathione. Addition of glutathione to cell culture media with concurrent exposure to PEI NPs proved to be insufficient for cytotoxicity reduction. Additionally, we compared internalization pathways of both PEI NPs and GSH NPs. NPs were only found in endosomes and no NPs were found free in the cytosol, as would be expected according to so called proton sponge hypothesis. Copyright © 2017 Elsevier B.V. All rights reserved.

CADASIL: Ultrastructural insights into the morphology of granular osmiophilic material.

PubMed

Lorenzi, Teresa; Ragno, Michele; Paolinelli, Francesca; Castellucci, Clara; Scarpelli, Marina; Morroni, Manrico

2017-03-01

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary systemic vascular disorder. Granular osmiophilic material (GOM) is its ultrastructural marker. We reviewed tissue biopsies from CADASIL patients to establish whether ultrastructural observations help clarify the pathogenic mechanism of CADASIL. Given the resemblance of the GOM deposits to the immunoglobulin deposits seen in glomerulonephritis and focal segmental glomerulosclerosis (FSGS), their morphologies were investigated and compared. Skin, skeletal muscle, kidney, and pericardium tissue biopsies from 13 patients with a clinical and molecular diagnosis of CADASIL, and kidney biopsies from five patients with IgA nephropathy and five patients with primary FSGS were subjected to ultrastructural examination. In CADASIL patients, several GOM deposits from all sites were partially or totally surrounded by an electron-lucent halo. The deposits frequently had a more electron-dense portion with a regular outline on the inner side and a less osmiophilic, looser outer side displaying a less regular profile. The uniformly dense deposits tended to be more osmiophilic if located close to the cell membrane and less osmiophilic if laid farther away from it. The immunoglobulin deposits from the glomerulonephritis and FSGS patients lacked both the granular pattern and the halo. This study demonstrates that GOM deposits may have a nonuniform morphology and describes in detail an electron-lucent halo surrounding several of them. It is conceivable that the halo is the morphological evidence and possibly the cause of an aberrant NOTCH3 processing, already suspected to be involved in CADASIL.

Responses of photosynthetic properties and chloroplast ultrastructure of two moss crusts from a desert biological soil crust to supplementary UV-B radiation

NASA Astrophysics Data System (ADS)

Hui, Rong; Li, Xinrong; Zhao, Yang; Pan, Yanxia

2016-04-01

Our understanding of plant responses to supplementary ultraviolet-B (UV-B) radiation due to stratospheric ozone depletion has improved over recent decades. However, research on biological soil crusts (BSCs) is scarce and it remains controversial. Laboratory studies were conducted to investigate the influence of UV-B radiation on the Bryum argenteum and Didymodon vinealis isolated from BSCs, which are both dominant species in moss crusts found within patches of shrubs and herbs in the Tengger Desert of northern China. The aim of the current work was to evaluate whether supplementary UV-B radiation affected photosynthetic properties and chloroplast ultrastructure of two moss crusts and whether response differences were observed between the crusts. Four levels of UV-B radiation of 2.75 (control), 3.08, 3.25, and 3.41 W m-2 was achieved using fluorescence tube systems for 10 days, simulating 0, 6, 9, and 12% of stratospheric ozone at the latitude of Shapotou, respectively. We measured photosynthetic apparatus as assessed by chlorophyll a fluorescence parameters, photosynthetic pigment contents, and observations of chloroplast ultrastructure. Additionally, soluble proteins and UV-B absorbing compounds were simultaneously investigated. The results of this study showed that chlorophyll a fluorescence parameters (i.e., the maximal quantum yield of PSII photochemistry, the effective quantum yield of PSII photochemistry, and photochemical quenching coefficient), photosynthetic pigment contents, soluble protein contents, total flavonoid contents and the ultrastructure were negatively influenced by elevated UV-B radiation and the degree of detrimental effects significantly increased with the intensity of UV-B radiation. Moreover, results demonstrated that the negative effects on photosynthesis and chloroplast ultrastructure were more serious in B. argenteum than that in D. vinealis. These results may not only provide a potential mechanism for supplemental UV-B effects on

Cytotoxic Effect on Human Myeloma Cells and Leukemic Cells by the Agaricus blazei Murill Based Mushroom Extract, Andosan™

PubMed Central

Holien, Toril; Mirlashari, Mohammad Reza; Misund, Kristine

2017-01-01

Agaricus blazei Murill is an edible mushroom of the Basidiomycetes family, which has been found to contain a number of compounds with antitumor properties, such as proteoglycans and ergosterol. In the present investigation, we show that the commercial mushroom product Andosan, which contains 82.4% Agaricus blazei Murill, together with medicinal mushrooms Hericium erinaceus (14.7%) and Grifola frondosa (2.9%), has a cytotoxic effect on primary myeloma cells, other myeloma cell lines, and leukemia cell lines in vitro. Although the exact content and hence the mechanisms of action of the Andosan extract are unknown, we have found in this investigation indications of cell cycle arrest when myeloma cell lines are cultivated with Andosan. This may be one of the possible explanations for the cytotoxic effects of Andosan. PMID:29238712

Cytotoxic Effect on Human Myeloma Cells and Leukemic Cells by the Agaricus blazei Murill Based Mushroom Extract, Andosan™.

PubMed

Tangen, Jon-Magnus; Holien, Toril; Mirlashari, Mohammad Reza; Misund, Kristine; Hetland, Geir

2017-01-01

Agaricus blazei Murill is an edible mushroom of the Basidiomycetes family, which has been found to contain a number of compounds with antitumor properties, such as proteoglycans and ergosterol. In the present investigation, we show that the commercial mushroom product Andosan, which contains 82.4% Agaricus blazei Murill, together with medicinal mushrooms Hericium erinaceus (14.7%) and Grifola frondosa (2.9%), has a cytotoxic effect on primary myeloma cells, other myeloma cell lines, and leukemia cell lines in vitro. Although the exact content and hence the mechanisms of action of the Andosan extract are unknown, we have found in this investigation indications of cell cycle arrest when myeloma cell lines are cultivated with Andosan. This may be one of the possible explanations for the cytotoxic effects of Andosan.

In Vitro Evaluations of Cytotoxicity of Eight Antidiabetic Medicinal Plants and Their Effect on GLUT4 Translocation

PubMed Central

Kadan, Sleman; Saad, Bashar; Sasson, Yoel; Zaid, Hilal

2013-01-01

Despite the enormous achievements in conventional medicine, herbal-based medicines are still a common practice for the treatment of diabetes. Trigonella foenum-graecum, Atriplex halimus, Olea europaea, Urtica dioica, Allium sativum, Allium cepa, Nigella sativa, and Cinnamomum cassia are strongly recommended in the Greco-Arab and Islamic medicine for the treatment and prevention of diabetes. Cytotoxicity (MTT and LDH assays) of the plant extracts was assessed using cells from the liver hepatocellular carcinoma cell line (HepG2) and cells from the rat L6 muscle cell line. The effects of the plant extracts (50% ethanol in water) on glucose transporter-4 (GLUT4) translocation to the plasma membrane was tested in an ELISA test on L6-GLUT4myc cells. Results obtained indicate that Cinnamomon cassia is cytotoxic at concentrations higher than 100 μg/mL, whereas all other tested extracts exhibited cytotoxic effects at concentrations higher than 500 μg/mL. Exposing L6-GLUT4myc muscle cell to extracts from Trigonella foenum-graecum, Urtica dioica, Atriplex halimus, and Cinnamomum verum led to a significant gain in GLUT4 on their plasma membranes at noncytotoxic concentrations as measured with MTT assay and the LDH leakage assay. These findings indicate that the observed anti-diabetic properties of these plants are mediated, at least partially, through regulating GLUT4 translocation. PMID:23606883

Cytotoxicity and genotoxicity of natural resin-based experimental endodontic sealers.

PubMed

Silva, Gleyce O; Cavalcanti, Bruno N; Oliveira, Tatiana R; Bin, Claudia V; Camargo, Samira E A; Camargo, Carlos H R

2016-05-01

The development of endodontic sealers based on natural resins seems to be promising, given their improved biological properties. This study evaluated the cytotoxic and genotoxic effects of two experimental root canal sealers, based on extracts from Copaifera multijuga and Ricinus communis (castor oil polymer), comparing them to synthetic resin-based sealers: a single methacrylate-based, a multi-methacrylate-based, and an epoxy resin-based sealers. Sealers were prepared, set, and exposed to cell culture medium for 24 h at 37 °C with CO2. V79 cells were exposed to serial dilutions of the extracts of each sealer for 24 h. Cell viability was measured by the MTT assay and genotoxicity was assessed by the formation of micronuclei. The single methacrylate-based sealer had the most cytotoxic effects, with significant reduction in cell viability in all dilutions of the extract. The castor oil polymer-based sealer was, on the other hand, the most biocompatible sealer, with no cytotoxic effects at any concentration. All tested sealers were not genotoxic, excepting the single methacrylate-based sealer. The tested natural resin-based sealers presented low cytotoxic and no genotoxic effects on cell cultures. These results may suggest a good alternative to develop new endodontic sealers, in order to achieve better biological response and healing, when compared to commercially available sealers.

Induced molt using cassava meal. 2. Effects on eggshell quality, ultrastructure, and pore density in late-phase laying hens.

PubMed

Gongruttananun, N

2018-03-01

This experiment was conducted to investigate the effect of a non-fasting induced molt using cassava meal on the eggshell quality, ultrastructure, and porosity in late-phase (74 wk old) H&N Brown laying hens. Hens were randomly assigned to 3 treatments of 90 birds each: 1) Controls with no induced molt (CONT); 2) molted by full feeding with cassava meal for 3 wk (FP3); and 3) molted by full feeding with cassava meal for 4 wk (FP4). Following the treatments, groups 2 and 3 were fed a pullet developer diet for 3 weeks. During the molt period, the birds were exposed to an 8L:16D photoperiod and had access to drinking water at all times. Thereafter, all hens were fed a layer diet (17% CP) and exposed to a 16L:8D photoperiod until the end of the study. Compared to the CONT treatment, significant reductions (P < 0.05) in shell weight, thickness, and breaking strength were identified on the sixth d of feeding the molt diet. Significant (P < 0.05) improvements in these parameters were observed for the FP3 and FP4 treatments during the post-molt period, with the greater degree in the FP4 treatment. In addition, scanning electron microscopy revealed a smaller size of mammillary knobs accompanied by a higher density of mammillae in eggs taken from the molted treatments. Evidence of type B mammillae was detected in an egg produced by the CONT hens, whereas confluent and cuffing mammillae were observed in an egg taken from the FP4 birds. Reduced pore densities were found in the molted treatments in some periods of the post-molt production as compared to the CONT treatment. It was concluded that feeding the cassava molt diet for 4 wk could be an effective non-fasting molt method for improving eggshell quality, ultrastructure, and porosity in post-molt laying hens.

Histologic and ultrastructural evaluation of fresh and frozen-thawed human ovarian xenografts in nude mice.

PubMed

Nisolle, M; Casanas-Roux, F; Qu, J; Motta, P; Donnez, J

2000-07-01

To compare histologic and ultrastructural characteristics of fresh and frozen-thawed human ovarian cortical tissue grafted into nude mice. Experimental prospective study. An academic research environment. Ovarian biopsy specimens were obtained from 13 women undergoing laparoscopy for tubal ligation or infertility. Forty nude mice. A minilaparotomy was performed to place fresh and frozen-thawed ovarian grafts subcutaneously (sc) or intraperitoneally (ip). Removal of the ovarian grafts was performed at 24 days. [1] the follicular population, [2] fibrosis, [3] vascularization of the grafted tissue, and [4] ultrastructural evaluation. A greater fibrosis relative surface area was noted in frozen-thawed transplanted tissue than in fresh transplants. Regardless of this fibrosis, a similar follicular density was observed in fresh and frozen-thawed ovarian tissue 24 days after transplantation. Active angiogenesis was proved by both immunohistochemical study of the vascular endothelial growth factor and morphometric study of the vascular network. Normal ultrastructural characteristics were noted in frozen-thawed ovarian biopsies. Angiogenesis allows implantation of the graft even if it has been cryopreserved and thawed similarly to implantation of fresh tissue. The greater fibrosis observed in grafts after cryopreservation and implantation does not seem to affect the primordial and primary ovocyte population and their ultrastructural characteristics, but further studies must be conducted to prove that after cryopreservation and transplantation, ovocytes may achieve full maturation and fertilization.

Cytotoxic constituents of Achillea clavennae from Montenegro.

PubMed

Trifunović, Snezana; Vajs, Vlatka; Juranić, Zorica; Zizak, Zeljko; Tesević, Vele; Macura, Slobodan; Milosavljević, Slobodan

2006-05-01

Examination of the aerial parts of Achillea clavennae afforded eight guaianolides (1-8), three bisabolenes (9-11), four flavonols (12-15), sesamin (lignan) and isofraxidin (coumarin). The structures of the new compounds (2, 4, 5, 7 and 10) were determined by spectroscopic methods. The antiproliferative action of 2, 8, 9 and 12 were tested to HeLa, K562 and Fem-X human cancer cell lines. Guaianolides 2 (9alpha-acetoxyartecanin) and 8 (apressin) showed significant cytotoxic effects to all tested lines and inducumenone (9) exhibited a moderate activity. The most active was flavonol centaureidin (12), already known as cytotoxic compound.

Comparative cytotoxicity of periodontal bacteria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stevens, R.H.; Hammond, B.F.

1988-11-01

The direct cytotoxicity of sonic extracts (SE) from nine periodontal bacteria for human gingival fibroblasts (HGF) was compared. Equivalent dosages (in terms of protein concentration) of SE were used to challenge HGF cultures. The cytotoxic potential of each SE was assessed by its ability to (1) inhibit HGF proliferation, as measured by direct cell counts; (2) inhibit 3H-thymidine incorporation in HGF cultures; or (3) cause morphological alterations of the cells in challenged cultures. The highest concentration (500 micrograms SE protein/ml) of any of the SEs used to challenge the cells was found to be markedly inhibitory to the HGFs bymore » all three of the criteria of cytotoxicity. At the lowest dosage tested (50 micrograms SE protein/ml); only SE from Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Fusobacterium nucleatum caused a significant effect (greater than 90% inhibition or overt morphological abnormalities) in the HGFs as determined by any of the criteria employed. SE from Capnocytophaga sputigena, Eikenella corrodens, or Wolinella recta also inhibited cell proliferation and thymidine incorporation at this dosage; however, the degree of inhibition (5-50%) was consistently, clearly less than that of the first group of three organisms named above. The SE of the three other organisms tested (Actinomyces odontolyticus, Bacteroides intermedius, and Streptococcus sanguis) had little or no effect (0-10% inhibition) at this concentration. The data suggest that the outcome of the interaction between bacterial components and normal resident cells of the periodontium is, at least in part, a function of the bacterial species.« less

Effects of serum on cytotoxicity of nano- and micro-sized ZnO particles

NASA Astrophysics Data System (ADS)

Hsiao, I.-Lun; Huang, Yuh-Jeen

2013-09-01

Although an increasing number of in vitro studies are being published regarding the cytotoxicity of nanomaterials, the components of the media for toxicity assays have often varied according to the needs of the scientists. Our aim for this study was to evaluate the influence of serum—in this case, fetal bovine serum—in a cell culture medium on the toxicity of nano-sized (50-70 nm) and micro-sized (<1 μm) ZnO on human lung epithelial cells (A549). The nano- and micro-sized ZnO both exhibited their highest toxicity when exposed to serum-free media, in contrast to exposure in media containing 5 or 10 % serum. This mainly comes not only from the fact that ZnO particles in the serum-free media have a higher dosage-per-cell ratio, which results from large aggregates of particles, rapid sedimentation, absence of protein protection, and lower cell growth rate, but also that extracellular Zn2+ release contributes to cytotoxicity. Although more extracellular Zn2+ release was observed in serum-containing media, it did not contribute to nano-ZnO cytotoxicity. Furthermore, non-dissolved particles underwent size-dependent particle agglomeration, resulting in size-dependent toxicity in both serum-containing and serum-free media. A low correlation between cytotoxicity and inflammation endpoints in the serum-free medium suggested that some signaling pathways were changed or induced. Since cell growth, transcription behavior for protein production, and physicochemical properties of ZnO particles all were altered in serum-free media, we recommend the use of a serum-containing medium when evaluating the cytotoxicity of NPs.

Therapeutic drug monitoring of antimetabolic cytotoxic drugs

PubMed Central

Lennard, L

1999-01-01

Therapeutic drug monitoring is not routinely used for cytotoxic agents. There are several reasons, but one major drawback is the lack of established therapeutic concentration ranges. Combination chemotherapy makes the establishment of therapeutic ranges for individual drugs difficult, the concentration-effect relationship for a single drug may not be the same as that when the drug is used in a drug combination. Pharmacokinetic optimization protocols for many classes of cytotoxic compounds exist in specialized centres, and some of these protocols are now part of large multicentre trials. Nonetheless, methotrexate is the only agent which is routinely monitored in most treatment centres. An additional factor, especially in antimetabolite therapy, is the existence of pharmacogenetic enzymes which play a major role in drug metabolism. Monitoring of therapy could include assay of phenotypic enzyme activities or genotype in addition to, or instead of, the more traditional measurement of parent drug or drug metabolites. The cytotoxic activities of mercaptopurine and fluorouracil are regulated by thiopurine methyltransferase (TPMT) and dihydropyrimidine dehydrogenase (DPD), respectively. Lack of TPMT functional activity produces life-threatening mercaptopurine myelotoxicity. Very low DPD activity reduces fluorouracil breakdown producing severe cytotoxicity. These pharmacogenetic enzymes can influence the bioavailability, pharmacokinetics, toxicity and efficacy of their substrate drugs. PMID:10190647

Cytotoxicity induced by fine particulate matter (PM2.5) via mitochondria-mediated apoptosis pathway in human cardiomyocytes.

PubMed

Yang, Xiaozhe; Feng, Lin; Zhang, Yannan; Hu, Hejing; Shi, Yanfeng; Liang, Shuang; Zhao, Tong; Fu, Yang; Duan, Junchao; Sun, Zhiwei

2018-06-06

Although the strongly causal associations were between fine particulate matter (PM 2.5 ) and cardiovascular disease, the toxic effect and potential mechanism of PM 2.5 on heart was poorly understood. Thus, the aim of this study was to evaluate the cardiac toxicity of PM 2.5 exposure on human cardiomyocytes (AC16). The cell viability was decreased while the LDH release was increased in a dose-dependent way after AC16 exposed to PM 2.5 . The reactive oxygen species (ROS) generation and production of malondialdehyde (MDA) were increased followed by the decreasing in superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). The damage of mitochondria was observed by ultra-structural analysis and MMP measurement. The apoptotic rate of AC16 were markedly elevated which was triggered by PM 2.5 . In addition, the proteins involved in mitochondria- mediated apoptosis pathway were measured. The protein levels of Caspase-3, Caspase-9 and Bax were up-regulated while the anti-apoptotic protein, Bcl-2 was down-regulated after AC16 exposed to PM 2.5 . In summary, our results demonstrated that mitochondria-mediated apoptosis pathway played a critical role in PM 2.5 -induced myocardial cytotoxicity in AC16, which suggested that PM 2.5 may contribute to cardiac dysfunction. Copyright © 2018 Elsevier Inc. All rights reserved.

Investigation of T-2 Mycotoxin-Induced Cytotoxicity in vitro and Protective Effects of Flavonoid Compounds

DTIC Science & Technology

1986-01-01

Quercetin , a flavonoid compound was able to decrease the effect of T-2 toxin when the drug was added within an hour of mixing the T-2 toxin with the...were examined microscopically using a Neubauer hemocytometer and viability of at least 200 cells was deter- mined. Quercetin or other flavonold... quercetin and additional OMSO had a cytotoxic effect on the thymocytes. RESULTS Figure 1 shows the results of 8 separate experiments performed at 2 week

Antibacterial and Cytotoxic Activity of Compounds Isolated from Flourensia oolepis

PubMed Central

Joray, Mariana Belén; Trucco, Lucas Daniel; González, María Laura; Napal, Georgina Natalia Díaz; Palacios, Sara María; Bocco, José Luis; Carpinella, María Cecilia

2015-01-01

The antibacterial and cytotoxic effects of metabolites isolated from an antibacterial extract of Flourensia oolepis were evaluated. Bioguided fractionation led to five flavonoids, identified as 2′,4′-dihydroxychalcone (1), isoliquiritigenin (2), pinocembrin (3), 7-hydroxyflavanone (4), and 7,4′-dihydroxy-3′-methoxyflavanone (5). Compound 1 showed the highest antibacterial effect, with minimum inhibitory concentration (MIC) values ranging from 31 to 62 and 62 to 250 μg/mL, against Gram-positive and Gram-negative bacteria, respectively. On further assays, the cytotoxic effect of compounds 1–5 was determined by MTT assay on acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia (CML) cell lines including their multidrug resistant (MDR) phenotypes. Compound 1 induced a remarkable cytotoxic activity toward ALL cells (IC50 = 6.6–9.9 μM) and a lower effect against CML cells (IC50 = 27.5–30.0 μM). Flow cytometry was used to analyze cell cycle distribution and cell death by PI-labeled cells and by Annexin V/PI staining, respectively. Upon treatment, 1 induced cell cycle arrest in the G2/M phase accompanied by a strong induction of apoptosis. These results describe for the first time the antibacterial metabolites of F. oolepis extract, with 1 being the most effective. This chalcone also emerges as a selective cytotoxic agent against sensitive and resistant leukemic cells, highlighting its potential as a lead compound. PMID:26819623

Cytotoxic and clastogenic effects of soluble and insoluble compounds containing hexavalent and trivalent chromium.

PubMed Central

Levis, A. G.; Majone, F.

1981-01-01

Cr(III) and Cr(VI) compounds of varying solubilities have been tested in vitro for their ability to inhibit cell growth and nucleic acid and protein syntheses in BHK cells, to induce alterations in the mitotic cycle in HEp cells, and to increase the frequency of chromosomal aberrations and sister chromatid exchanges (SCE) in CHO cells. All Cr(VI) compounds, and particularly those containing soluble Cr(VI), such as potassium dichromate and zinc yellow, differentially inhibit macromolecular syntheses in BKH cells, that of DNA being always the most affected. Among Cr(III) compounds, which generally have very low cytotoxicity, chromite is particularly active, and inhibits cell growth and DNA synthesis even more than the poorly soluble Cr(VI) compounds. Preincubation in growth medium, with or without metabolizing cell cultures, solubilizes considerable amounts of Cr(VI) from zinc yellow and chromite, but significant amounts are also obtained from the most insoluble Cr(VI) pigments. When BHK cells are treated with such preincubated solutions, reduction of soluble Cr(VI) to Cr(III) by cell metabolites is seen with all Cr(VI) compounds, accompanied by decreased cytotoxicity. The same differences between Cr(VI) and Cr(III) compounds apply to the cytotoxic effects on mitosis of HEp cells and the clastogenic effects on CHO cells. The activity of chromite, the only Cr(III) pigment capable of significantly increasing the frequency of SCE, is due to contamination with soluble Cr(VI). In contrast to the very low cytotoxicity of Cr(III), much higher chromium levels are detected in the cells incubated with soluble Cr(III) than with the same concentrations of soluble Cr(VI). 50% and 75% of chromium accumulated in the cells during treatments with Cr(VI) and Cr(III) respectively remains firmly bound to the cells, even when they are incubated for up to 48 h in normal growth medium. Chromium accumulated in the cells after treatment with Cr(III) is most probably bound to the cell

Ultrastructural characteristics of type A epithelioid cells during BCG-granulomatosis and treatment with lysosomotropic isoniazid.

PubMed

Shkurupii, V A; Kozyaev, M A; Nadeev, A P

2006-04-01

We studied BCG-granulomas, their cellular composition, and ultrastructure of type A epithelioid cells in the liver of male BALB/c mice with spontaneous granulomatous inflammation. The animals received free isoniazid or isoniazid conjugated with lysosomotropic intracellularly prolonged matrix (dialdehyde dextran, molecular weight 65-75 kDa). Lysosomotropic isoniazid was accumulated in the vacuolar apparatus of epithelioid cells and produced a stimulatory effect on plastic processes in these cells.

Tripartite differentiation (squamous, glandular, and melanocytic) of a primary cutaneous neuroendocrine carcinoma. An immunocytochemical and ultrastructural study.

PubMed

Isimbaldi, G; Sironi, M; Taccagni, G; Declich, P; Dell'Antonio, A; Galli, C

1993-06-01

We report a case of primary cutaneous neuroendocrine carcinoma (PCNEC) with squamous, glandular, and melanocytic differentiation and associated Bowen disease. The paranuclear globular positivity of low-molecular-weight cytokeratins agrees with the ultrastructural observations of paranuclear fibrous bodies in the small neuroendocrine cells, while the diffuse cytoplasmic positivity corresponds to the sparse intermediate filaments in large cells with squamous differentiation. "Transitional forms" are characterized by both diffuse and globular cytoplasmic positivity for cytokeratins and by the ultrastructural evidence of neuroendocrine and squamous features. Therefore the ultrastructural demonstration of intracytoplasmic tonofibrils and tonofilaments, intercellular glandular lumina, lined by well-formed microvilli, and immature premelanosomes in the neurosecretory cells supports the proposed tripartite differentiation of neuroendocrine cells of this case of PCNEC.

Ultrastructural Changes in Human Striated Muscle Using Three Methods of Training

ERIC Educational Resources Information Center

Penman, Kenneth A.

1969-01-01

There have been many attempts to describe what happens when a muscle gets stronger. However, little has been done to examine possible structural changes at the ultrastructural level when a muscle becomes stronger or hypertrophied. (CK)

Decreasing effect of an anti-Nfa1 polyclonal antibody on the in vitro cytotoxicity of pathogenic Naegleria fowleri

PubMed Central

Jeong, Seok-Ryoul; Kang, Su-Yeon; Lee, Sang-Chul; Song, Kyoung-Ju; Im, Kyung-il

2004-01-01

The nfa1 gene was cloned from a cDNA library of pathogenic Naegleria fowleri by immunoscreening; it consisted of 360 bp and produced a 13.1 kDa recombinant protein (rNfa1) that showed the pseudopodia-specific localization by immunocytochemistry in the previous study. Based on the idea that the pseudopodia-specific Nfa1 protein mentioned above seems to be involved in the pathogenicity of N. fowleri, we observed the effect of an anti-Nfa1 antibody on the proliferation of N. fowleri trophozoites and the cytotoxicity of N. fowleri trophozoites on the target cells. The proliferation of N. fowleri trophozoites was inhibited after being treated with an anti-Nfa1 polyclonal antibody in a dose-dependent manner for 48 hrs. By a light microscope, CHO cells co-cultured with N. fowleri trophozoites (group I) for 48 hrs showed severe morphological destruction. On the contrary, CHO cells co-cultured with N. fowleri trophozoites and anti-Nfa1 polyclonal antibody (1:100 dilution) (group II) showed less destruction. In the LDH release assay results, group I showed 50.6% cytotoxicity, and group II showed 39.3%. Consequently, addition of an anti-Nfa1 polyclonal antibody produced a decreasing effect of in vitro cytotoxicity of N. fowleri in a dosedependent manner. PMID:15060338

Evaluation of cytotoxic effects of six self-etching adhesives with direct and indirect contact tests.

PubMed

Kusdemir, Mahmut; Gunal, Solen; Ozer, Fusun; Imazato, Satoshi; Izutani, Naomi; Ebisu, Shigeyuki; Blatz, Markus B

2011-01-01

This study evaluated the cytotoxicity of self-etching primers/adhesives by direct contact and dentin barrier tests. The three two-step self-etching systems Clearfil SE Bond (CSE), Clearfil Protect Bond (CPB), Prime&Bond NT/NRC (PB) and one-step self-etching systems Reactmer Bond (RB), Clearfil Tri-S Bond (CTS), and Adper Prompt L-Pop (AP) were examined. In direct contact tests, L929 cells were cultured in the presence of diluted solutions (50, 20, 10, and 1%) of primer/conditioner of adhesive systems. For dentin barrier tests, each system was applied onto 0.5 or 1.5 mm thick human dentin assembled in a simple pulp chamber device and incubated for 24 h at 37°C to make the diffusive components contact the L929 cells placed at the bottom of the chamber. The cytotoxic effects were assessed by MTT assay. Cell culture without application of any primers/adhesives served as the control for both tests. One-way ANOVA and Tukey HSD tests were used for statistical analyses. The direct contact tests demonstrated that CSE and CPB were less toxic than the other materials at all dilutions. In the dentin barrier tests, toxic effects of materials were reduced with an increase in thickness of intervening dentin. CSE and CPB showed less cytotoxicity than the other adhesives (p<0.05) when applied to 0.5 mm-thick dentin, and CSE was the least toxic in the 1.5 mm-dentin group (p<0.05). Dentin thickness positively affected biocompatibility of the tested bonding systems. Two-step self-etching systems with HEMA-based primers were more biocompatible than other self-etching adhesives.

Ultrastructural dynamics of human reproduction, from ovulation to fertilization and early embryo development.

PubMed

Familiari, Giuseppe; Heyn, Rosemarie; Relucenti, Michela; Nottola, Stefania A; Sathananthan, A Henry

2006-01-01

This study describes the updated, fine structure of human gametes, the human fertilization process, and human embryos, mainly derived from assisted reproductive technology (ART). As clearly shown, the ultrastructure of human reproduction is a peculiar multistep process, which differs in part from that of other mammalian models, having some unique features. Particular attention has been devoted to the (1) sperm ultrastructure, likely "Tygerberg (Kruger) strict morphology criteria"; (2) mature oocyte, in which the MII spindle is barrel shaped, anastral, and lacking centrioles; (3) three-dimensional microarchitecture of the zona pellucida with its unique supramolecular filamentous organization; (4) sperm-egg interactions with the peculiarity of the sperm centrosome that activates the egg and organizes the sperm aster and mitotic spindles of the embryo; and (5) presence of viable cumulus cells whose metabolic activity is closely related to egg and embryo behavior in in vitro as well as in vivo conditions, in a sort of extraovarian "microfollicular unit." Even if the ultrastructural morphodynamic features of human fertilization are well understood, our knowledge about in vivo fertilization is still very limited and the complex sequence of in vivo biological steps involved in human reproduction is only partially reproduced in current ART procedures.

Evaluation of Genotoxic and Cytotoxic Effects in Human Peripheral Blood Lymphocytes Exposed In Vitro to Neonicotinoid Insecticides News

PubMed Central

Calderón-Segura, María Elena; Gómez-Arroyo, Sandra; Villalobos-Pietrini, Rafael; Martínez-Valenzuela, Carmen; Carbajal-López, Yolanda; Calderón-Ezquerro, María del Carmen; Cortés-Eslava, Josefina; García-Martínez, Rocío; Flores-Ramírez, Diana; Rodríguez-Romero, María Isabel; Méndez-Pérez, Patricia; Bañuelos-Ruíz, Enrique

2012-01-01

Calypso (thiacloprid), Poncho (clothianidin), Gaucho (imidacloprid), and Jade (imidacloprid) are commercial neonicotinoid insecticides, a new class of agrochemicals in México. However, genotoxic and cytotoxic studies have not been performed. In the present study, human peripheral blood lymphocytes (PBL) were exposed in vitro to different concentrations of the four insecticides. The genotoxic and cytotoxic effects were evaluated using the alkaline comet and trypan blue dye exclusion assays. DNA damage was evaluated using two genotoxicity parameters: tail length and comet frequency. Exposure to 9.5 × 10−6 to 5.7 × 10−5 M Jade; 2.8 × 10−4 to 1.7 × 10−3 M Gaucho; 0.6 × 10−1 to 1.4 × 10−1 M Calypso; 1.2 × 10−1 to 9.5 × 10−1 M Poncho for 2 h induced a significant increase DNA damage with a concentration-dependent relationship. Jade was the most genotoxic of the four insecticides studied. Cytotoxicity was observed in cells exposed to 18 × 10−3 M Jade, 2.0 × 10−3 M Gaucho, 2.0 × 10−1 M Calypso, 1.07 M Poncho, and cell death occurred at 30 × 10−3 M Jade, 3.3 × 10−3 M Gaucho, 2.8 × 10−1 M Calypso, and 1.42 M Poncho. This study provides the first report of genotoxic and cytotoxic effects in PBL following in vitro exposure to commercial neonicotinoid insecticides. PMID:22545045

Long-term exposure of rapeseed (Brassica napus L.) to ZnO nanoparticles: anatomical and ultrastructural responses.

PubMed

Mousavi Kouhi, Seyed Mousa; Lahouti, Mehrdad; Ganjeali, Ali; Entezari, Mohammad H

2015-07-01

Rapid development of nanotechnology in recent years has raised concerns about nanoparticle (NPs) release into the environment and its adverse effects on living organisms. The present study is the first comprehensive report on the anatomical and ultrastructural changes of a variety of cells after long-term exposure of plant to NPs or bulk material particles (BPs). Light and electron microscopy revealed some anatomical and ultrastructural modifications of the different types of cell in the root and leaf, induced by both types of treatment. Zinc oxide (ZnO) BPs-induced modifications were surprisingly more than those induced by ZnO NPs. The modifications induced by ZnO BPs or ZnO NPs were almost similar to those induced by excess Zn. Zn content of the root and leaf of both ZnO NPs- and ZnO BPs-treated plants was severely increased, where the increase was greater in the plants treated with ZnO BPs. Overall, these results indicate that the modifications induced by ZnO particles can be attributed, at least partly, to the Zn(2+) dissolution by ZnO particles rather than their absorption by root and their subsequent effects.

Synthesis of silver nanoparticles using flavonoids: hesperidin, naringin and diosmin, and their antibacterial effects and cytotoxicity

NASA Astrophysics Data System (ADS)

Sahu, Nidhi; Soni, Deepika; Chandrashekhar, B.; Satpute, D. B.; Saravanadevi, Sivanesan; Sarangi, B. K.; Pandey, R. A.

2016-07-01

Three different flavonoids -hesperidin, naringin and diosmin (constituents of citrus plants) were used for the synthesis of silver nanoparticles (AgNPs). Aqueous solutions of pure flavonoids (0.2 mg mL-1) mixed with 1 mM AgNO3 solution were exposed to bright sunlight to prepare the nanoparticles. Characterization of the synthesized nanoparticles by UV-Visible spectrophotometer, X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy revealed that the synthesized silver nanoparticles were 10-80 nm in size and polydispersed in nature. Bactericidal effect against common pathogens and cytotoxicity of the synthesized silver nanoparticles was investigated on human promyelocytic leukemic (HL-60) cells. It is concluded that AgNPs synthesized using Naringin as reducing agent showed higher stability and better antibacterial and cytotoxic activities.

Histochemical and ultrastructural studies on the calcareous corpuscles and eggs of Taenia taeniaeformis and Dipylidium caninum.

PubMed

Khalifa, Refaat M A; Mazen, Nawal A M; Marawan, Aziza M A; Thabit, Hasnaa T M

2011-08-01

Calcareous corpuscles were noticed by several previous workers to be present in larval and adult cestodes without knowing their function. However, nothing was mentioned in the available literature about distribution of these corpuscles and their density, structure and composition in different parts of the body of different cestodes. Hence, in the present work, a comparative study of their distribution, density, histochemical and ultrastructural characters in different parts of the body was performed in Taenia taeniaeformis and Dipylidium caninum. Due to the presence of the eggs in their gravid segments, their histochemical and ultrastructural characteristics were also studied. It was found that the size, location and density of the calcareous bodies were different in different body parts of the same and the other cestode. Histochemically, the main component of these corpuscles was calcium; while other constituents as polysaccharides, lipids, protrins and mucopolysaccharides were found in their outer rim. Ultrastructurally, they were quite similar in the two studied cestodes and different stages of their development were exhibited. Histochemically, the eggs of both cestodes were similar in their contents. However, some ultrastructural differences have been demonstrated particularly in relation to the size and shape of the rods in the embryophore and the structures in between the embryophore and onchosphere.

In vitro assessment of the genotoxic and cytotoxic effects of boiled juice (tucupi) from Manihot esculenta Crantz roots.

PubMed

Cunha, L A; Mota, T C; Cardoso, P C S; Alcântara, D D F Á; Burbano, R M R; Guimarães, A C; Khayat, A S; Rocha, C A M; Bahia, M O

2016-10-05

The population of Pará (a state in Brazil) has a very characteristic food culture, as a majority of the carbohydrates consumed are obtained from cassava (Manihot esculenta Crantz) derivatives. Tucupi is the boiled juice of cassava roots that plays a major role in the culinary footprint of Pará. Before boiling, this juice is known as manipueira and contains linamarin, a toxic glycoside that can decompose to hydrogen cyanide. In this study, the cytotoxic and genotoxic effects of tucupi on cultured human lymphocytes were assessed using the comet assay and detection of apoptosis and necrosis by differential fluorescent staining with acridine orange-ethidium bromide. Tucupi concentrations (v/v) were determined using the methylthiazole tetrazolium biochemical test. Concentrations of tucupi that presented no genotoxic effects (2, 4, 8, and 16%) were used in our experiments. The results showed that under our study conditions, tucupi exerted no genotoxic effects; however, cytotoxic effects were observed with cell death mainly induced by necrosis. These effects may be related to the presence of hydrogen cyanide in the juice.

Spermatological characteristics of the genus Taenia inferred from the ultrastructural study on Taenia hydatigena.

PubMed

Miquel, Jordi; Khallaayoune, Khalid; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

2015-01-01

The present study attempts to establish the sperm ultrastructure baseline for Taenia hydatigena, which is essential for the future research on the location of specific proteins involved in spermatogenesis in this species. Thus, the ultrastructural organisation of the mature spermatozoon is described by means of transmission electron microscopy. Live tapeworms were obtained from an experimentally infected dog in the Department of Pathology and Public Health of the Agronomic and Veterinary Institute Hassan II of Rabat (Morocco). The spermatozoon of T. hydatigena is a filiform cell, which is tapered at both extremities and lacks mitochondria. It exhibits all the characteristics of type VII spermatozoon of tapeworms, namely a single axoneme, a crested body, spiralled cortical microtubules and nucleus, a periaxonemal sheath and intracytoplasmic walls. Other interesting characteristics are the presence of a 2000 nm long apical cone in its anterior extremity and only the axoneme in its posterior extremity. The ultrastructural characters of the spermatozoon of T. hydatigena are compared with those of other cestodes studied to date, with particular emphasis on representatives of the genus Taenia.

Peculiarities of ultrastructure of Chlorella cells growing aboard the Bion-10 during 12 days

NASA Astrophysics Data System (ADS)

Popova, A. F.; Sytnik, K. M.

The ultrastructure of Chlorella cells grown in darkness on a solid agar medium with organic additions aboard the Bion-1O biosatellite was studied. Certain differences in submicroscopic organization of organelles in the experimental cells were revealed compared to the Earth control. The changes are registered mainly in ultrastructure of energetic organelles - mitochondria and plastids of the experimental cells, in particular, an increase of mitochondria and their cristae size, as well as an increase of the total volume of mitochondrion per cell were established. The decrease of the starch amount in the plastid stroma and the electron density of the latter was also observed. In many experimental cells, the increase of condensed chromatin in the nuclei has been noted. Ultrastructural rearrangements in cells after laboratory experiment realized according to the thermogram registered aboard the Bion-10 were insignificant compared to the flight experiment. Data obtained are compared to results of space flight experiments carried out aboard the Bion-9 (polycomponent aquatic system) and the orbital station Mir (solid agar medium).

Effect of boric acid on antioxidant enzyme activity, lipid peroxidation, and ultrastructure of midgut and fat body of Galleria mellonella.

PubMed

Büyükgüzel, Ender; Büyükgüzel, Kemal; Snela, Milena; Erdem, Meltem; Radtke, Katarzyna; Ziemnicki, Kazimierz; Adamski, Zbigniew

2013-04-01

Boric acid is widely used as an insecticide, acaricide, herbicide, and fungicide and also during various industrial processings. Hence, numerous populations are subjects to this toxic compound. Its action on animals is still not fully known and understood. We examined the effect of boric acid on larvae of greater wax moth (Galleria mellonella). The chemical appeared to be toxic for larvae, usually in a concentration-dependent manner. Exposed groups revealed increased lipid peroxidation and altered activity of catalase, superoxide dismutase, glutathione S-transferase, and glutathione peroxidase. We also observed changes of ultrastructure, which were in tune with biochemical assays. We suggest that boric acid has a broad mode of action, which may affect exposed larvae, and even if sublethal, they may lead to disturbances within exposed populations.

A semi high-throughput method for screening small bispecific antibodies with high cytotoxicity.

PubMed

Sugiyama, Aruto; Umetsu, Mitsuo; Nakazawa, Hikaru; Niide, Teppei; Onodera, Tomoko; Hosokawa, Katsuhiro; Hattori, Shuhei; Asano, Ryutaro; Kumagai, Izumi

2017-06-06

Small bispecific antibodies that induce T-cell-mediated cytotoxicity have the potential to damage late-stage tumor masses to a clinically relevant degree, but their cytotoxicity is critically dependent on their structural and functional properties. Here, we constructed an optimized procedure for identifying highly cytotoxic antibodies from a variety of the T-cell-recruiting antibodies engineered from a series of antibodies against cancer antigens of epidermal growth factor receptor family and T-cell receptors. By developing and applying a set of rapid operations for expression vector construction and protein preparation, we screened the cytotoxicity of 104 small antibodies with diabody format and identified some with 10 3 -times higher cytotoxicity than that of previously reported active diabody. The results demonstrate that cytotoxicity is enhanced by synergistic effects between the target, epitope, binding affinity, and the order of heavy-chain and light-chain variable domains. We demonstrate the importance of screening to determine the critical rules for highly cytotoxic antibodies.

Pseudomonas aeruginosa invasion and cytotoxicity are independent events, both of which involve protein tyrosine kinase activity.

PubMed

Evans, D J; Frank, D W; Finck-Barbançon, V; Wu, C; Fleiszig, S M

1998-04-01

Pseudomonas aeruginosa clinical isolates exhibit invasive or cytotoxic phenotypes. Cytotoxic strains acquire some of the characteristics of invasive strains when a regulatory gene, exsA, that controls the expression of several extracellular proteins, is inactivated. exsA mutants are not cytotoxic and can be detected within epithelial cells by gentamicin survival assays. The purpose of this study was to determine whether epithelial cell invasion precedes and/or is essential for cytotoxicity. This was tested by measuring invasion (gentamicin survival) and cytotoxicity (trypan blue staining) of PA103 mutants deficient in specific exsA-regulated proteins and by testing the effect of drugs that inhibit invasion for their effect on cytotoxicity. A transposon mutant in the exsA-regulated extracellular factor exoU was neither cytotoxic nor invasive. Furthermore, several of the drugs that inhibited invasion did not prevent cytotoxicity. These results show that invasion and cytotoxicity are mutually exclusive events, inversely regulated by an exsA-encoded invasion inhibitor(s). Both involve host cell protein tyrosine kinase (PTK) activity, but they differ in that invasion requires Src family tyrosine kinases and calcium-calmodulin activity. PTK inhibitor drugs such as genistein may have therapeutic potential through their ability to block both invasive and cytotoxicity pathways via an action on the host cell.

Cytotoxic Steroids from the Vietnamese Soft Coral Sinularia conferta.

PubMed

Ngoc, Ninh Thi; Huong, Pham Thi Mai; Thanh, Nguyen Van; Chi, Nguyen Thi Phuong; Dang, Nguyen Hai; Cuong, Nguyen Xuan; Nam, Nguyen Hoai; Thung, Do Cong; Kiem, Phan Van; Minh, Chau Van

2017-03-01

Twelve steroids, including five new compounds 1-5, were isolated and structurally elucidated from a methanol extract of the Vietnamese soft coral Sinularia conferta. Their cytotoxic effects against three human cancer cell lines, lung carcinoma (A-549), cervical adenocarcinoma (HeLa), and pancreatic epithelioid carcinoma (PANC-1), were evaluated using 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assays. Among isolated compounds, 10 exhibited potent cytotoxic effects on all three tested cell lines with IC 50 values of 3.64±0.18, 19.34±0.42, and 1.78±0.69 µM, respectively.

Responses of photosynthetic properties and chloroplast ultrastructure of Bryum argenteum from a desert biological soil crust to elevated ultraviolet-B radiation.

PubMed

Hui, Rong; Li, Xinrong; Chen, Cuiyun; Zhao, Xin; Jia, Rongliang; Liu, Lichao; Wei, Yongping

2013-04-01

Our understanding of plant responses to enhanced ultraviolet-B (UV-B) radiation has improved over recent decades. However, research on cryptogams is scarce and it remains controversial whether UV-B radiation causes changes in physiology related to photosynthesis. To investigate the effects of supplementary UV-B radiation on photosynthesis and chloroplast ultrastructure in Bryum argenteum Hedw., specimens were cultured for 10 days under four UV-B treatments (2.75, 3.08, 3.25 and 3.41 W m(-2) ), simulating depletion of 0% (control), 6%, 9% and 12% of stratospheric ozone at the latitude of Shapotou, a temperate desert area of northwest China. Analyses showed malondialdehyde content significantly increased, whereas chlorophyll (Chl) fluorescence parameters and Chl contents decreased with increased UV-B intensity. These results corresponded with changes in thylakoid protein complexes and chloroplast ultrastructure. Overall, enhanced UV-B radiation leads to significant decreases in photosynthetic function and serious destruction of the chloroplast ultrastructure of B. argenteum. The degree of negative influences increased with the intensity of UV-B radiation. These results may not only provide a potential mechanism for supplemental UV-B effects on photosynthesis of moss crust, but also establish a theoretical basis for further studies of adaptation and response mechanisms of desert ecosystems under future ozone depletion. Copyright © Physiologia Plantarum 2012.

Evaluation of the genotoxic and cytotoxic effects of crude extracts of Cordia ecalyculata and Echinodorus grandiflorus.

PubMed

da Silva, Cristiano José; Bastos, Jairo Kenupp; Takahashi, Catarina Satie

2010-02-03

Cordia ecalyculata Vell. and Echinodorus grandiflorus (Cham. & Schltdl.) Micheli are extensively used in Brazil as therapeutic preparations for indigenous groups and the general population. These plants have been used in the folk medicine as: tonic, diuretic, anti-inflammatory, appetite suppressants, for the treatment of snake bites, and weight loss. In this study, it was verified the possible cytotoxic and genotoxic effects of the crude extracts of. Cordia ecalyculata and Echinodorus grandiflorus, as well as their effectiveness in treating obesity. The Micronucleus Test was used for the evaluation of possible clastogenic and aneugenic effects, and the Comet Assay was used for the evaluation of single-strand and double-strand DNA breaks. The cytotoxic effects of the crude extracts were verified by PCE/NCE ratio. Swiss mice (Mus musculus) were used as the experimental model. It was observed a significant (P<0.05) increase, dose-independent, in the average frequency of micronucleated erythrocytes in peripheral blood in mice treated with either the Cordia ecalyculata or Echinodorus grandiflorus extracts, in comparison with the negative control. There were no significant differences (P>0.05) in the frequency of micronucleated polychromatic erythrocytes for both extract treatment. We observed that treatment with the Cordia ecalyculata extract at concentrations of 1000 and 2000 mg/kg bw resulted in a PCE/NCE ratio that was larger (P<0.05) than the negative control. After 15 days of daily treatment, a dose of 2000 mg/kg bw of either phytotherapeutic did not reduce body mass gain or the amount of food consumed by Swiss mice when compared with the negative control (P>0.05). The results of this study allowed us to infer that the crude extracts of Cordia ecalyculata and Echinodorus grandiflorus do not display cytotoxic or genotoxic activities. However, they do possess weak clastogenic activity (without significance) on peripheral blood cells. Contrary to commonly held beliefs

Cytotoxic active constituents of essential oils of Curcuma longa and Curcuma zanthorrhiza.

PubMed

Schmidt, Erich; Ryabchenko, Boris; Wanner, Juergen; Jäger, Walter; Jirovetz, Leopold

2015-01-01

The polar and apolar fractions of Curcuma longa and C. zanthorriza enriched by ar-turmerone, ar-curcumene and xanthorrizol were screened for cytotoxic activity against the HeLa cell line. Actinomycin D and curcumin were used as reference samples, both known for their cytotoxic properties. Amongst all fractions tested, the xanthorrizol fraction (CC50: 26.1 ± 1.9 μM) showed the strongest cytotoxic properties similar to those of curcumin (CC50: 8.1 ± 1.7 μM). Further studies also revealed that the cytotoxic effects of the extracts and pure compounds are caused by apoptosis induction identified by the cleaved form of PARP protein.

Cytotoxic effects and apoptosis induction of enrofloxacin in hepatic cell line of grass carp (Ctenopharyngodon idellus).

PubMed

Liu, Bo; Cui, Yanting; Brown, Paul B; Ge, Xianping; Xie, Jun; Xu, Pao

2015-12-01

We determined the effect of enrofloxacin on the lactate dehydrogenase (LDH) release, reactive oxygen species (ROS), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), malondialdehyde (MDA), mitochondria membrane potential (ΔΨm) and apoptosis in the hepatic cell line of grass carp (Ctenopharyngodon idellus). Cultured cells were treated with different concentrations of enrofloxacin (12.5-200 ug/mL) for 24 h. We found that the cytotoxic effect of enrofloxacin was mediated by apoptosis, and that this apoptosis occurred in a dose-dependent manner. The doses of 50,100 and 200 μg/mL enrofloxacin increased the LDH release and MDA concentration, induced cell apoptosis and reduced the ΔΨm compared to the control. The highest dose of 200 ug/mL enrofloxacin also significantly induced apoptosis accompanied by ΔΨm disruption and ROS generation and significantly reduced T-AOC and increased MDA concentration compared to the control. Our results suggest that the dose of 200 ug/mL enrofloxacin exerts its cytotoxic effect and produced ROS via apoptosis by affecting the mitochondria of the hepatic cells of grass carp. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ultrastructure of the mycangium of the southern pine beetle, Dendroctonus frontalis (Coleoptera: Curculionidae, Scolytinae): complex morphology for complex interactions

Treesearch

Cetin Yuceer; Chuan-Yu Hsu; Nadir Erbilgin; Kier D. Klepzig

2011-01-01

The southern pine beetle (SPB) (Dendroctonus frontalis Zimmermann) is the most economically important pest of southern pine forests. Beetles carry fungal cells within specialised cuticular structures, called mycangia. Little is known about the mycangia ultrastructure or function. We used cryo-fracturing and scanning electron microscopy to examine the ultrastructural...

Bcl-2 inhibitors potentiate the cytotoxic effects of radiation in Bcl-2 overexpressing radioresistant tumor cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hara, Takamitsu; Omura-Minamisawa, Motoko; Chao Cheng

Purpose: Bcl-2, an inhibitor of apoptosis frequently shows elevated expression in human tumors, thus resulting in resistance to radiation therapy. Therefore, inhibiting Bcl-2 function may enhance the radiosensitivity of tumor cells. Tetrocarcin A (TC-A) and bcl-2 antisense oligonucleotides exhibit antitumor activity by inhibiting Bcl-2 function and transcription, respectively. We investigated whether these antitumor agents would enhance the cytotoxic effects of radiation in tumor cells overexpressing Bcl-2. Methods and materials: We used HeLa/bcl-2 cells, a stable Bcl-2-expressing cell line derived from wild-type HeLa (HeLa/wt) cells. Cells were incubated with TC-A and bcl-2 antisense oligonucleotides for 24 h after irradiation, and cellmore » viability was then determined. Apoptotic cells were quantified by flow cytometric assay. Results: The HeLa/bcl-2 cells were more resistant to radiation than HeLa/wt cells. At concentrations that are not inherently cytotoxic, both TC-A and bcl-2 antisense oligonucleotides increased the cytotoxic effects of radiation in HeLa/bcl-2 cells, but not in HeLa/wt cells. However, in HeLa/bcl-2 cells, additional treatment with TC-A in combination with radiation did not significantly increase apoptosis. Conclusions: The present results suggest that TC-A and bcl-2 antisense oligonucleotides reduce radioresistance of tumor cells overexpressing Bcl-2. Therefore, a combination of radiotherapy and Bcl-2 inhibitors may prove to be a useful therapeutic approach for treating tumors that overexpress Bcl-2.« less

Prototheca zopfii Induced Ultrastructural Features Associated with Apoptosis in Bovine Mammary Epithelial Cells

PubMed Central

Shahid, Muhammad; Wang, Jianfang; Gu, Xiaolong; Chen, Wei; Ali, Tariq; Gao, Jian; Han, Dandan; Yang, Rui; Fanning, Séamus; Han, Bo

2017-01-01

Prototheca zopfii infections are becoming global concerns in humans and animals. Bovine protothecal mastitis is characterized by deteriorating milk quality and quantity, thus imparting huge economic losses to dairy industry. Previous published studies mostly focused on the prevalence and characterization of P. zopfii from mastitis. However, the ultrastructural pathomorphological changes associated with apoptosis in bovine mammary epithelial cells (bMECs) are not studied yet. Therefore, in this study we aimed to evaluate the in vitro comparative apoptotic potential of P. zopfii genotype-I and -II on bMECs using flow cytometry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed fast growth rate and higher adhesion capability of genotype-II in bMECs as compared with genotype-I. The viability of bMECs infected with P. zopfii genotype-II was significantly decreased after 12 h (p < 0.05) and 24 h (p < 0.01) in comparison with control cells. Contrary, genotype-I couldn't show any significant effects on cell viability. Moreover, after infection of bMECs with genotype-II, the apoptosis increased significantly at 12 h (p < 0.05) and 24 h (p < 0.01) as compared with control group. Genotype-I couldn't display any significant effects on cell apoptosis. The host specificity of P. zopfii was also tested in mouse osteoblast cells, and the results suggest that genotype-I and -II could not cause any significant apoptosis in these cell lines. SEM interpreted the pathomorphological alterations in bMECs after infection. Adhesion of P. zopfii with cells and further disruption of cytomembrane validated the apoptosis caused by genotype-II under SEM. While genotype-1 couldn't cause any significant apoptosis in bMECs. Furthermore, genotype-II induced apoptotic manifested specific ultrastructure features, like cytoplasmic cavitation, swollen mitochondria, pyknosis, cytomembrane disruption, and appearance of apoptotic bodies under TEM. The

Cytotoxic and apoptotic effects of different extracts of Artemisia biennis Willd. on K562 and HL-60 cell lines

PubMed Central

Tayarani-Najaran, Zahra; Makki, Farideh-Sadat; Alamolhodaei, Nafiseh-Sadat; Mojarrab, Mahdi; Emami, Seyed Ahmad

2017-01-01

Objective(s): Artemisia is a genus of herbs and small shrubs forms an important part of natural vegetation in Iran. It has been reported that several Artemisia species possess anti-proliferative effects. Considering the value of this genus in anti-cancer researches we have chosen Artemisia biennis for cytotoxic and mechanistic studies. Materials and Methods: In this study we have investigated the cytotoxic and apoptotic effects of petroleum ether, dichloromethane, ethyl acetate, ethanol, and ethanol: water (1:1 v/v) extracts of A. biennis Willd. on two cancer human cell lines (K562 and HL-60) and J774 as normal cells. Results: CH2Cl2 extract was found to have the highest anti-proliferative effect on cancer cells. IC50 values obtained in AlamarBlue® assay for CH2Cl2 extract were 64.86 and 54.31 µg/ml on K562 and HL-60 cells respectively. In flow cytometry histogram of the cells treated with CH2Cl2 extract, sub-G1 peak was induced. DNA fragmentation, increased in the level of Bax and cleavage of PARP protein all showed the induction of apoptosis with CH2Cl2 extract after 48 hr contact with cells. Conclusion: The results can corroborate the cytotoxic and apoptotic effects of the CH2Cl2 extract of A. biennis on the K562 and HL-60 cancer cell lines. PMID:28293393

In vitro cytotoxicity evaluation of elemental ions released from different prosthodontic materials.

PubMed

Elshahawy, Waleed M; Watanabe, Ikuya; Kramer, Phillip

2009-12-01

This study investigated the cytotoxicity of elemental ions contained in four fixed prosthodontic materials (gold, nickel-chromium, stainless-steel alloys and CAD-CAM ceramics). According to the determination of elements released from prosthodontic materials by using inductively coupled plasma mass spectroscopy, similar amounts of elements Pd, Ag, Zn, Cu, Ni, Cr, Mo, Be, Fe, Al, and K were prepared as salt solutions. Wells with a tenfold higher concentration of the tested elements were used as positive controls, while a well without any tested element was used as a negative control. These salt solutions were tested for cytotoxicity by culturing mouse L-929 fibroblasts in the salt solutions for a 7-day period of incubation. Then, the percentage of viable cells for each element was measured using trypan blue exclusion assay. The data (n=5) were statistically analyzed by ANOVA/Tukey test (p<0.05). The results showed a statistically significant difference for the cytotoxic effect of the tested elements salt solutions. For the released element concentrations the lowest percentage of viable cells (mean+/-SD) was evident with Zn, Cu or Ni indicating that they are the highly toxic elements. Be and Ag were found to be intermediate in cytotoxic effect. Fe, Cr, Mo, Al, Pd or K were found to be the least cytotoxic elements. Zn and Cu released from gold alloys, and Ni released from nickel-chromium alloys, which are commonly used as fixed prosthodontic restorations, show evidence of a high cytotoxic effect on fibroblast cell cultures.

Synergistic effects of ICI 182,780 on the cytotoxicity of cisplatin in cervical carcinoma cell lines.

PubMed

García-López, Patricia; Rodríguez-Dorantes, Mauricio; Pérez-Cárdenas, Enrique; Cerbón, Marco; Mohar-Betancourt, Alejandro

2004-06-01

We investigated the ability of the novel pure antiestrogen ICI 182,780 to modulate the cytotoxic effects of cisplatin in several cervical cancer cell lines. The effect of cisplatin alone and cisplatin combined with ICI 182,780 on cellular death was studied using an assay based on a tetrazolium dye (sodium 3'-[1-(phenylamino-carbonyl)-3,4-tetrazolium], XTT). Before and after treatment with ICI 182,780, expression of the estrogen and progesterone receptor genes were assessed by a reverse transcriptase polymerase chain reaction (RT-PCR). Cell-cycle modifications after combined treatment with cisplatin and ICI 182,780 were studied by flow cytometry. Analysis of the data by the isobologram method showed that the combination of ICI 182,780 and cisplatin produced a synergistic antiproliferative effect in cervical cancer cells. The effect of ICI 182,780 on the cytotoxicity of cisplatin could be mediated, at least partially, by inhibition of estrogen and progesterone gene expression and by arresting the cell cycle at the G(2)/M phase. Our results suggest that ICI 182,780 can improve the efficacy of cisplatin in cancer cells and that this antihormonal drug therapy may be a useful candidate for further evaluation in combination with antineoplastic drugs, particularly cisplatin, in the treatment of cancer.

Effects of polysaccharide peptide (PSP) from Coriolus versicolor on the pharmacokinetics of cyclophosphamide in the rat and cytotoxicity in HepG2 cells.

PubMed

Chan, Siu-Lung; Yeung, John H K

2006-05-01

Polysaccharide peptide (PSP), isolated from Coriolus versicolor COV-1, has been shown to restore the immunological effects against cyclophosphamide-induced immuno-suppression, although the mechanism(s) involved remain uncertain. This study investigated the PSP-cyclophosphamide interaction by studying the effects of PSP on the pharmacokinetic of cyclophosphamide in the rat and the effect of PSP on the cytotoxic effects of cyclophosphamide on a cancer cell line (HepG2 cells). In the pharmacokinetic studies in the rat, acute pre-treatment of PSP (4 micromol/kg/day, i.p.) decreased the clearance (CL) of cyclophosphamide by 31%, with a concomitant increase in the area under concentration-time curve (AUC) by 44%, and prolongation of the plasma half-life (T(1/2)) by 43%. Sub-chronic pre-treatment of PSP (2 micromol/kg/day, i.p., 3 days) decreased the CL of cyclophosphamide by 33%, with a concomitant increase in the AUC by 50%, and prolongation of the plasma T(1/2) by 34%. In cytotoxicity studies using HepG2 cells, non-toxic dose of PSP (1-10 microM) enhanced the cytotoxicity of cyclophosphamide. PSP at 10 microM further decreased HepG2 cell viability by 22% compared to when cyclophosphamide was present alone. In summary, PSP enhanced the cytotoxic effect of cyclophosphamide on a cancer cell line in vitro and altered the pharmacokinetics of cyclophosphamide in vivo in the rat. Both of these effects may be beneficial in the use of PSP as an adjunct to cyclophosphamide treatment.

Application of Coffee Silverskin in cosmetic formulations: physical/antioxidant stability studies and cytotoxicity effects.

PubMed

Rodrigues, Francisca; Gaspar, Carlos; Palmeira-de-Oliveira, Ana; Sarmento, Bruno; Helena Amaral, M; P P Oliveira, M Beatriz

2016-01-01

Currently, there is an increasing interest of cosmetic industry on natural extracts. The inclusion of antioxidants in topical formulations can contribute to minimize oxidative stress in the skin, which has been associated with aging. Also, questions of sustainability are leading to the study of new cosmetic ingredients obtained from food by-products. Coffee Silverskin (CS) is a food by-product with established antioxidant activity that has not yet been incorporated into a topical formulation. The aim of this study was to evaluate the physical and microbiological stabilities and antioxidant activity of a hand cream formulation containing 2.5% (w/w) of CS extract upon production and after 6 months of shelf-life and in vitro safety/cytotoxicity on skin cell lines after production. The in vitro cytotoxicity was evaluated with MTS and LDH assays, at different concentrations, in HaCaT and HFF-1 cells. Formulations were stored at 25 °C/65% RH and 40 °C/75% RH. Physical, microbiological, and antioxidant stabilities were evaluated by centrifugation, viscosity, total colony count, DPPH and total phenolic content (TPC). The hand cream containing 2.5% (w/w) of CS extract showed stable physical characteristics independently of the storage conditions. The DPPH activity and TPC of the CS formulation were significantly higher compared with those of the base formulation. However, during storage, the antioxidant activity decreases slightly. Microbiological quality was also confirmed. No cytotoxic effects were observed. It is possible to suggest that this formulation is stable under extreme conditions and safe for topical use.

Ultrastructure of pea and cress root statocytes exposed to high gradient magnetic field

NASA Astrophysics Data System (ADS)

Belyavskaya, N. A.; Chernishov, V. I.; Polishchuk, O. V.; Kondrachuk, A. V.

As it was demonstrated by Kuznetsov & Hasenstein (1996) the high gradient magnetic field (HGMF) can produce a ponderomotive force that results in displacements of amyloplasts and causes the root response similar to the graviresponse. It was suggested that the HGMF could allow to imitate the effects of gravity in microgravity and/or change them in laboratory conditions correspondingly, as well as to study statolith-related processes in graviperception. Therefore, the correlation between the direction of the ponderomotive force resulting in statolith displacements and the direction of the HGMF-induced plant curvature can be the serious argument to support this suggestion and needs the detailed ultrastructural analysis. Seeds of dicotyledon Pisum sativum L. cv. Damir-2 and monocotyledon Lepidium sativum L. cv. P896 were soaked and grown in a vertical position on moist filter paper in chambers at room temperature. Tips of primary roots of vertical control, gravistimulated and exposed to HGMF seedlings were fixed for electron microscopy using conventional techniques. At ultrastructural level, we observed no significant changes in the volume of the individual statocytes or amyloplasts, relative volumes of cellular organelles (except vacuoles), number of amyloplasts per statocyte or surface area of endoplasmic reticulum. No consistent contacts between amyloplasts and any cellular structures, including plasma membrane, were revealed at any stage of magneto- and gravistimulation. By 5 min after onset of magnetostimulation, amyloplasts were located along cell wall distant from magnets. In HGMF, the locations of amyloplasts in columella cells were similar to those in horizontally-oriented roots up to 1 h stimulation. In the latter case, there were sometimes cytoplasmic spherical bodies with a dense vesicle-rich cytoplasm in pea statocytes, which were absent in seedlings exposed to HGMF. In cress root statocytes, both gravi- and magnetostimulation were found to cause the

In Vitro Cytotoxic Evaluation of MgO Nanoparticles and Their Effect on the Expression of ROS Genes

PubMed Central

Kumaran, Rangarajulu Senthil; Choi, Yong-Keun; Singh, Vijay; Song, Hak-Jin; Song, Kyung-Guen; Kim, Kwang Jin; Kim, Hyung Joo

2015-01-01

Water-dispersible MgO nanoparticles were tested to investigate their cytotoxic effects on oxidative stress gene expression. In this in vitro study, genes related to reactive oxygen species (ROS), glutathione S-transferase (GST) and catalase, were quantified using real-time polymerase chain reactions (molecular level) and molecular beacon technologies (cellular level). The monodispersed MgO nanoparticles, 20 nm in size, were used to treat human cancer cell lines (liver cancer epithelial cells) at different concentrations (25, 75 and 150 µg/mL) and incubation times (24, 48 and 72 h). Both the genetic and cellular cytotoxic screening methods produced consistent results, showing that GST and catalase ROS gene expression was maximized at 150 µg/mL nanoparticle treatment with 48 h incubation. However, the genotoxic effect of MgO nanoparticles was not significant compared with control experiments, which indicates its significant potential applications in nanomedicine as a diagnostic and therapeutic tool. PMID:25854426

Effects of moist cold stratification on germination, plant growth regulators, metabolites and embryo ultrastructure in seeds of Acer morrisonense (Sapindaceae).

PubMed

Chen, Shun-Ying; Chou, Shih-Han; Tsai, Ching-Chu; Hsu, Wen-Yu; Baskin, Carol C; Baskin, Jerry M; Chien, Ching-Te; Kuo-Huang, Ling-Long

2015-09-01

Breaking of seed dormancy by moist cold stratification involves complex interactions in cells. To assess the effect of moist cold stratification on dormancy break in seeds of Acer morrisonense, we monitored percentages and rates of germination and changes in plant growth regulators, sugars, amino acids and embryo ultrastructure after various periods of cold stratification. Fresh seeds incubated at 25/15 °C for 24 weeks germinated to 61%, while those cold stratified at 5 °C for 12 weeks germinated to 87% in 1 week. Neither exogenous GA3 nor GA4 pretreatment significantly increased final seed germination percentage. Total ABA content of seeds cold stratified for 12 weeks was reduced about 3.3-fold, to a concentration similar to that in germinated seeds (radicle emergence). Endogenous GA3 and GA7 were detected in 8-week and 12-week cold stratified seeds but not in fresh seeds. Numerous protein and lipid bodies were present in the plumule, first true leaves and cotyledons of fresh seeds. Protein and lipid bodies decreased greatly during cold stratification, and concentrations of total soluble sugars and amino acids increased. The major non-polar sugars in fresh seeds were sucrose and fructose, but sucrose increased and fructose decreased significantly during cold stratification. The major free amino acids were proline and tryptophan in fresh seeds, and proline increased and tryptophan decreased during cold stratification. Thus, as dormancy break occurs during cold stratification seeds of A. morrisonense undergo changes in plant growth regulators, proteins, lipids, sugars, amino acids and cell ultrastructure. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Comparative cytotoxic and genotoxic potential of 13 drinking water disinfection by-products using a microplate-based cytotoxicity assay and a developed SOS/umu assay.

PubMed

Zhang, Shao-Hui; Miao, Dong-Yue; Tan, Li; Liu, Ai-Lin; Lu, Wen-Qing

2016-01-01

The implications of disinfection by-products (DBPs) present in drinking water are of public health concern because of their potential mutagenic, carcinogenic and other toxic effects on humans. In this study, we selected 13 main DBPs found in drinking water to quantitatively analyse their cytotoxicity and genotoxicity using a microplate-based cytotoxicity assay and a developed SOS/umu assay in Salmonella typhimurium TA1535/pSK1002. With the developed SOS/umu test, eight DBPs: 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-fura3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H]-furanone (MX), dibromoacetonitrile (DBN), iodoacetic acid (IA), bromochloroacetonitrile (BCN), bromoacetic acid (BA), trichloroacetonitrile (TCN), dibromoacetic acid (DBA) and dichloroacetic acid (DCA) were significantly genotoxic to S. typhimurium. Three DBPs: chloroacetic acid (CA), trichloroacetic acid (TCA) and dichloroacetonitrile (DCN) were weakly genotoxic, whereas the remaining DBPs: chloroacetonitrile (CN) and chloral hydrate (CH) were negative. The rank order in decreasing genotoxicity was as follows: MX > DBN > IA > BCN > BA > TCN > DBA > DCA > CA, TCA, DCN > CN, CH. MX was approximately 370 000 times more genotoxic than DCA. In the microplate-based cytotoxicity assay, cytotoxic potencies of the 13 DBPs were compared and ranked in decreasing order as follows: MX > IA > DBN > BCN > BA > TCN > DCN > CA > DCA > DBA > CN > TCA > CH. MX was approximately 19 200 times more cytotoxic than CH. A statistically significant correlation was found between cytotoxicity and genotoxicity of the 13 DBPs in S. typhimurium. Results suggest that microplate-based cytotoxicity assay and the developed SOS/umu assay are feasible tools for analysing the cytotoxicity and genotoxicity of DBPs, particularly for comparing their toxic intensities quantitatively. © The Author 2015. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e

Antibacterial and cytotoxic effect of biologically synthesized silver nanoparticles using aqueous root extract of Erythrina indica lam

NASA Astrophysics Data System (ADS)

Rathi Sre, P. R.; Reka, M.; Poovazhagi, R.; Arul Kumar, M.; Murugesan, K.

2015-01-01

Simple, yet an effective and rapid approach for the green synthesis of silver nanoparticles (Ag NPs) using root extract of Erythrina indica and its in vitro antibacterial activity was tried against human pathogenic bacteria and its cytotoxic effect in breast and lung cancer cell lines has been demonstrated in this study. Various instrumental techniques were adopted to characterize the synthesized Ag NPs viz. UV-Vis (Ultra violet), FTIR (Fourier Transform Infrared), XRD (X-ray diffraction), DLS (Dynamic light scattering), HR TEM (High-resolution transmission electron microscopy), EDX (Energy-dispersive X-ray spectroscopy). Surface plasmon spectra for Ag NPs are centered nearly at 438 nm with dark brown color. FTIR analysis revealed the presence of terpenes, phenol, flavonols and tannin act as effective reducing and capping agents for converting silver nitrate to Ag NPs. The synthesized Ag NPs were found to be spherical in shape with size in the range of 20-118 nm. Moreover, the synthesized Ag NPs showed potent antibacterial activity against Gram positive and Gram negative bacteria and these biologically synthesized nanoparticles were also proved to exhibit excellent cytotoxic effect on breast and lung cancer cell lines.

Immunomodulatory properties of medicinal mushrooms: differential effects of water and ethanol extracts on NK cell-mediated cytotoxicity.

PubMed

Lu, Chia-Chen; Hsu, Ya-Jing; Chang, Chih-Jung; Lin, Chuan-Sheng; Martel, Jan; Ojcius, David M; Ko, Yun-Fei; Lai, Hsin-Chih; Young, John D

2016-10-01

Medicinal mushrooms have been used for centuries in Asian countries owing to their beneficial effects on health and longevity. Previous studies have reported that a single medicinal mushroom may produce both stimulatory and inhibitory effects on immune cells, depending on conditions, but the factors responsible for this apparent dichotomy remain obscure. We show here that water and ethanol extracts of cultured mycelium from various species (Agaricus blazei Murrill, Antrodia cinnamomea, Ganoderma lucidum and Hirsutella sinensis) produce opposite effects on NK cells. Water extracts enhance NK cell cytotoxic activity against cancer cells, whereas ethanol extracts inhibit cytotoxicity. Water extracts stimulate the expression and production of cytolytic proteins (perforin and granulysin) and NKG2D/NCR cell surface receptors, and activate intracellular signaling kinases (ERK, JNK and p38). In contrast, ethanol extracts inhibit expression of cytolytic and cell surface receptors. Our results suggest that the mode of extraction of medicinal mushrooms may determine the nature of the immunomodulatory effects produced on immune cells, presumably owing to the differential solubility of stimulatory and inhibitory mediators. These findings have important implications for the preparation of medicinal mushrooms to prevent and treat human diseases. © The Author(s) 2016.

Cytotoxicity of Doxycycline Effluent Generated by the Fenton Process

PubMed Central

Borghi, Alexandre Augusto; Stephano, Marco Antônio; Monteiro de Souza, Paula; Alves Palma, Mauri Sérgio

2014-01-01

This study aims at determining the Minimum Inhibitory Concentration with Escherichia coli ATCC 25922 and cytotoxicity to L929 cells (ATCC CCL-1) of the waste generated by doxycycline degradation by the Fenton process. This process has shown promise in this treatment thanks mainly to the fact that the waste did not show any relevant inhibitory effect on the test organism and no cytotoxicity to L-929 cells, thus demonstrating that the antibiotic properties were inactivated. PMID:25379532

Identification of stable cytotoxic factors in the gas phase extract of cigarette smoke and pharmacological characterization of their cytotoxicity.

PubMed

Noya, Yoichi; Seki, Koh-Ichi; Asano, Hiroshi; Mai, Yosuke; Horinouchi, Takahiro; Higashi, Tsunehito; Terada, Koji; Hatate, Chizuru; Hoshi, Akimasa; Nepal, Prabha; Horiguchi, Mika; Kuge, Yuji; Miwa, Soichi

2013-12-06

Smoking is a major risk factor for atherosclerotic vascular diseases, but the mechanism for its genesis is unknown. We have recently shown that the gas phase of cigarette smoke (nicotine- and tar-free cigarette smoke extract; CSE) likely to reach the systemic circulation contains stable substances which cause cytotoxicity like plasma membrane damage and cell death in cultured cells, and also that the plasma membrane damage is caused through sequential activation of protein kinase C (PKC) and NADPH oxidase (NOX) and the resulting generation of reactive oxygen species (PKC/NOX-dependent mechanism), whereas cell death is caused through PKC/NOX-dependent and -independent mechanisms. To identify these stable substances, the CSE was prepared by passing the main-stream smoke of 10 cigarettes through a Cambridge glass fiber filter, trapping of the smoke in a vessel cooled at -80°C, and subsequent dissolution in 10ml of water. The CSE was fractionated into nine fractions using reversed-phase HPLC, and each fraction was screened for cytotoxicity in cultured cells, using propidium iodide uptake assay for cell membrane damage and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] reduction assay for cell viability. The cytotoxicity was positive in two of the nine fractions (Fr2 and Fr5). After extraction of the active fractions into dichloromethane, GC/MS analysis identified 2-cyclopenten-1-one (CPO) in Fr5 but none in Fr2. After derivatization of the active fractions with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine hydrochloride, GC/MS analysis identified acrolein, acetone and propionaldehyde in Fr2, and methyl vinyl ketone (MVK) in Fr5. After 4-h incubation, authentic acrolein and MVK induced concentration-dependent cytotoxicity with EC50 values of 75.9±8.2 and 47.0±8.0μM (mean±SEM; n=3), respectively, whereas acetone, propionaldehyde and CPO were without effect. However, after 24-h incubation, CPO induced concentration

Epidermal lipid in several cetacean species: ultrastructural observations.

PubMed

Pfeiffer, C J; Jones, F M

1993-09-01

The ultrastructure of the skin of four cetacean species, bottlenose dolphin (Tursiops truncatus) long-finned pilot whale (Globicephala melaena), humpback whale (Megaptera novaeangliae), and fin whale (Balaenoptera physalus) was investigated with particular reference to epidermal lipid. It has already been established that massive lipid reservoirs exist in whales, that the biochemical structures of cetacean lipids are unique, and that unusual intracellular lipid droplets appear in the epidermis. We report here some novel findings on scanning electron microscopic morphology of epidermal lipid, and on its ultrastructural morphology in general and specialized integumentary sites, including species not previously investigated. The intracellular epidermal lipid droplets were more extensive than lamellar body-derived intercellular lipid which is within the interstices of stratum externum cells. The intracellular droplets were spherical, highly variable in size ranging from 0.24 micron to 3.0 microns in diameter, appeared singly or were aggregated in cytoplasmic cavitations, and often were closely associated with epidermal cell nuclei. Evidence for exocytosis of the intracellular droplets was not observed. Significant numbers of intracellular lipid droplets are not observed in the epidermis of terrestrial mammals, so their presence is one of several aquatic specializations of the cetacean integument. Its full significance remains obscure, but it is more probably associated with epidermal cell metabolism than with secretion of lipid.

The ultrastructural features of the premalignant oral lesions.

PubMed

Olinici, Doiniţa; Cotrutz, Carmen Elena; Mihali, Ciprian Valentin; Grecu, Vasile Bogdan; Botez, Emanuela Ana; Stoica, Laura; Onofrei, Pavel; Condurache, Oana; Dimitriu, Daniela Cristina

2018-01-01

Premalignant oral lesions are among the most important risk factors for the development of oral squamocellular carcinoma. Recent population studies indicate a significant rise in the prevalence of leukoplakia, erythroplakia/erythroleukoplakia, actinic cheilitis, submucous fibrosis and erosive lichen planus. Since standard histopathological examination has numerous limitations regarding the accurate appreciation of potential malignant transformation, the present study aims to aid these evaluations using the transmission electron microscopy (TEM) technique, which emphasizes ultrastructural changes pertaining to this pathology. Oral mucosa fragments collected from 43 patients that were clinically and histopathologically diagnosed with leukoplakia, erosive actinic cheilitis and erosive lichen planus have been processed through the classic technique for the examination using TEM and were examined using a Philips CM100 transmission electron microscope. The electron microscopy study has confirmed the histopathological diagnosis of the tissue samples examined using photonic microscopy and has furthermore revealed a series of ultrastructural details that on the one hand indicate the tendency for malignant transformation, and on the other reveal characteristic features of tumor development. All the details furnished by TEM complete the overall picture of morphological changes, specific to these lesions, indicating the importance of using these techniques in establishing both a correct diagnosis and prognosis.

Ultrastructural findings in lung biopsy material from children with congenital heart defects.

PubMed Central

Meyrick, B.; Reid, L.

1980-01-01

The ultrastructural features of pulmonary arteries are described in lung biopsy material from 6 children with congenital heart defects. Right ventricular hypertrophy was found in all 6 children and increased pulmonary artery pressure in all but one. The presence of muscle in smaller and more peripheral arteries than expected for the age of the child was detected in all cases. Ultrastructural examination of the peripheral arteries revealed, for the first time, in the nonmuscular regions of human arterial walls, pericytes and intermediate cells (previously shown to be precursor smooth-muscle cells); in addition, new arterial muscle was found in the normally nonmuscular region. In the 4 cases where medial thickness of the normally muscular arteries was increased, the smooth-muscle cells were hypertrophied and the extracellular connective tissue increased. In all cases, junctions between endothelial cells and smooth-muscle cells, intermediate cells, or pericytes were found. These changes are similar to those described in the rat with hypoxia-induced pulmonary hypertension. In addition, in 2 of the 6 cases, bundles of nerve axons in Schwann cell sheaths were found in adventitial layer of small, intraacinar muscular arteries (not previously demonstrated ultrastructurally at this site in the human lung); varicosities with agranular and granular vesicles, probably adrenergic, were also identified. Images Figure 4 Figure 5 Figure 1 Figure 2 Figure 3 PMID:7446706

Modelling antibiotic and cytotoxic isoquinoline effects in Staphylococcus aureus, Staphylococcus epidermidis and mammalian cells.

PubMed

Cecil, Alexander; Ohlsen, Knut; Menzel, Thomas; François, Patrice; Schrenzel, Jacques; Fischer, Adrien; Dörries, Kirsten; Selle, Martina; Lalk, Michael; Hantzschmann, Julia; Dittrich, Marcus; Liang, Chunguang; Bernhardt, Jörg; Ölschläger, Tobias A; Bringmann, Gerhard; Bruhn, Heike; Unger, Matthias; Ponte-Sucre, Alicia; Lehmann, Leane; Dandekar, Thomas

2015-01-01

Isoquinolines (IQs) are natural substances with an antibiotic potential we aim to optimize. Specifically, IQ-238 is a synthetic analog of the novel-type N,C-coupled naphthylisoquinoline (NIQ) alkaloid ancisheynine. Recently, we developed and tested other IQs such as IQ-143. By utilizing genome-wide gene expression data, metabolic network modelling and Voronoi tessalation based data analysis - as well as cytotoxicity measurements, chemical properties calculations and principal component analysis of the NIQs - we show that IQ-238 has strong antibiotic potential for staphylococci and low cytotoxicity against murine or human cells. Compared to IQ-143, systemic effects are less pronounced. Most enzyme activity changes due to IQ-238 are located in the carbohydrate metabolism. Validation includes metabolite measurements on biological replicates. IQ-238 delineates key properties and a chemical space for a good therapeutic window. The combination of analysis methods allows suggestions for further lead development and yields an in-depth look at staphylococcal adaptation and network changes after antibiosis. Results are compared to eukaryotic host cells. Copyright © 2014 Elsevier GmbH. All rights reserved.

Effects of serum albumin on the degradation and cytotoxicity of single-walled carbon nanotubes.

PubMed

Ding, Yun; Tian, Rong; Yang, Zhen; Chen, Jianfa; Lu, Naihao

2017-03-01

Neutrophil myeloperoxidase (MPO) and peroxynitrite (ONOO - ) can oxidatively biodegrade carboxylated single-walled carbon nanotubes (SWCNTs). The protein-SWCNTs interactions will play an important role in the degradation and cytotoxicity of nanotubes. Here, we investigated the binding of bovine serum albumin (BSA, a common and well-characterized model blood serum protein) to SWCNTs, and found that the hydrophobic and electrostatic interactions might be crucial factors in stabilizing the binding of SWCNTs with BSA. The binding of BSA could impair SWCNTs biodegradation in vitro through the competitive adsorption to nanotube. Both SWCNTs and BSA-SWCNTs were significantly degraded in zymosan-stimulated macrophages, and the degradation degree was more for BSA-SWCNTs. The mechanism for SWCNTs degradation in activated macrophages was further investigated to demonstrate the dominant participation of MPO and ONOO - -driven pathways. Moreover, binding of BSA to SWCNTs reduced cytotoxicity and degraded nanotubes induced less cytotoxicity than non-degraded nanotubes. The binding of BSA may be an important determinant for the biodegradation and cytotoxicity of SWCNTs in inflammatory cells, and therefore, provide a new route to mitigate the potential toxicity of nanotubes in future biomedical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

In vitro and in vivo evidence of the cytotoxic and genotoxic effects of metal ions released by orthodontic appliances: A review.

PubMed

Martín-Cameán, Ana; Jos, Ángeles; Mellado-García, Pilar; Iglesias-Linares, Alejandro; Solano, Enrique; Cameán, Ana M

2015-07-01

Intraoral fixed orthodontic appliances are frequently used in the clinical practice of dentistry. They are made from alloys containing different metals at various percentages. The use of these appliances leads to the long-term exposure of patients to these materials, and the potential toxic effects of this exposure raises concerns about patient safety. Thus, the biocompatibility (corrosion behaviour and toxicity) of these materials has to be evaluated prior to clinical use. In the present report, the most recent studies in the scientific literature examining metal ion release from orthodontic appliances and the toxic effects of these ions have been reviewed with a special focus on cytotoxicity and genotoxicity. Previous studies suggest that a case-by-case safety evaluation is required to take into account the increasing variability of materials, their composition and the manufacturing processes. Moreover, in vivo toxicity studies in regard to metal release, cytotoxicity and genotoxicity are still scarce. Therefore, in vitro and in vivo monitoring studies are needed to establish cause-effect relationships between metal ion release and biomarkers of cytotoxicity and genotoxicity. Further investigations could be performed to elucidate the toxic mechanisms involved in the observed effects with a special emphasis on oxidative damage. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of resveratrol on protecting corneal epithelial cells from cytotoxicity caused by moxifloxacin and benzalkonium chloride.

PubMed

Tsai, Tzu-Yun; Chen, Ta-Ching; Wang, I-Jong; Yeh, Chao-Yuan; Su, Ming-Jai; Chen, Ruey-Hua; Tsai, Tzu-Hsun; Hu, Fung-Rong

2015-02-10

Moxifloxacin (MOX), a fourth generation fluoroquinolone (FQ), has a wide antibacterial spectrum, but may show cytotoxicity characterized by high productions of reactive oxygen species (ROS). This study investigated the protective role of a common antioxidant agent, resveratrol (trans-3,5,4'-trihydroxystilbene), against the cytotoxicity caused by MOX. Experiments were performed with a human corneal epithelial cell line (HCECs; ATCC-CRL-11515). Another commonly used FQ, levofloxacin (LEV), and the most commonly used preservatives, benzalkonium chloride (BAC), were also used for comparison with MOX. Cell viability and morphologic changes after treatment were evaluated with trypan blue exclusion assay, propidium iodine/annexin V-FITC staining, and flow cytometry. Chemiluminescence immunoassay was used for ROS quantification. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, wound healing assay, and intracellular detections of oxidative stress were performed to evaluate the effects of resveratrol. The MOX group, similar to the BAC group, showed significant cell shrinkage and death compared with the LEV group. High ROS production in HCECs of MOX group was observed both by chemiluminescence immunoassay and intracellular images. Within the observations of MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay, live cell images, and wound healing process in vitro, the cytotoxic effects of the MOX and BAC groups were opposed by resveratrol. Human corneal epithelial cells pretreated with resveratrol demonstrated better cell viability and healing rate in the early stage. The protective effects of antioxidant agents indicate that MOX, similar to BAC, causes oxidative stress-related cell damage. The results also inspired us to think about a "supplementary regimen" to increase safety and decrease the adverse effect in the treatment of corneal infections. Copyright 2015 The Association for Research in Vision and

Cytotoxicity and anti-inflammatory effects of zinc ions and eugenol during setting of ZOE in immortalized human oral keratinocytes grown as three-dimensional spheroids.

PubMed

Lee, Jung-Hwan; Lee, Hae-Hyoung; Kim, Kyoung-Nam; Kim, Kwang-Mahn

2016-05-01

The objective of this study is to assess the cytotoxic and anti-inflammatory effects of ZOE cement during setting in two-dimensional (2D) or three-dimensional (3D) cultures of immortalized human oral keratinocytes (IHOKs) with determining the extract components responsible for these effects. Extracts of mixed ZOE at different stages of setting were analyzed by a digital pH meter, ICP-MS, and GC-MS. Serial concentrations of extract and their mixture of ZnCl2, ZnSO4·H2O, and eugenol liquid were added to the 2D and 3D IHOK cultures to determine the half maximal effective concentration in investigating the cause of cytotoxicity by means of WST assay and to investigate mRNA expression levels of inflammatory cytokines by RT-PCR. Zn(2+) and eugenol (4-19 ppm) were detected in the extracts. In the early setting stage, significant cytotoxicity was observed in the 2D and 3D IHOK cultures (P<0.05). The EC50 of Zn(2+) from ZnCl2 was 5-44 ppm in both cultures, whereas the EC50 of eugenol was not detectable under 100 ppm. Along with the lower levels of inflammatory cytokine gene expressions in the extract, treatment of the 2D IHOKs with Zn(2+) alone and treatment of the 3D IHOKs with Zn(2+) plus eugenol resulted in significantly lower expression levels of IL-1β, IL-6, and IL-8 (P<0.05). The cytotoxic effect of ZOE on IHOKs was greater during the setting stage owing to the presence of Zn(2+). The anti-inflammatory response to ZOE was induced by a combination of Zn(2+) and eugenol. Cytotoxic and anti-inflammatory effects differed between the 2D and 3D IHOK cultures. Copyright © 2016. Published by Elsevier Ltd.

Characterization of Thermally Activated Metalloenediyne Cytotoxicity in Human Melanoma Cells.

PubMed

Keller, Eric J; Porter, Meghan; Garrett, Joy E; Varie, Meredith; Wang, Haiyan; Pollok, Karen E; Turchi, John J; Zaleski, Jeffrey M; Dynlacht, Joseph R

2018-05-15

ED, platinated PyED (Pt-PyED). Pt-PyED binds to DNA-like cisplatin, and much like PyED, cytotoxicity is greatly enhanced after treatment with the drug at elevated temperatures. However, in contrast to PyED, Pt-PyED is only minimally cytotoxic at 37°C, at concentrations at which cytotoxicity is enhanced by hyperthermia. Further development of cisplatin-based enediynes may result in compounds which, when activated, will possess multiple DNA binding modalities similar to cisplatin, but produce less side effects in tissues at normothermic temperatures.

Analysis of the changes in the basal cell region of oral lichen planus: An ultrastructural study

PubMed Central

Paul, Mayura; Shetty, Devi Charan

2013-01-01

Context: Oral lichen planus (OLP) affects 0.5-1% of the total world's population. The histological features of oral lichen planus were first described by Dubreuill in 1906. Despite the advent of various techniques, the etiology of lichen planus remains obscure, although many theories for the etiology have been proposed. Aims: By studying OLP electron microscopically, we shall be emphasizing on the cells and its interactions in specific/altered surroundings which would help us in hypothesizing the effects of its specific cell-to-cell interactions. Materials and Methods: A total of 20 cases of oral lichen planus were selected and categorized into erosive and nonerosive forms based upon clinical pattern and confirmed as lichen planus by histopathological analysis. Tissue specimens thus obtained were cut into two halves and fixed in appropriate fixatives, i.e., neutral buffered formalin for paraffin-embedded hematoxylin and eosin stained sections and 2.5% glutaraldehyde and 2% paraformaldehyde for electron microscopic purpose respectively. Results: Ultrastructural comparison among the two forms showed significant differences between them. The basal layer showed cytoplasmic processes, intercellular spaces, desmosomes, nuclei, and signs of degeneration. The erosive form showed elongated, narrow or irregular cytoplasmic projections whereas the nonerosive showed short and broad based projections. Conclusions: The present study confirms the ultrastructural findings of basal cells in OLP with previous authors findings. Besides this, the categorization of the ultrastructural differences between erosive and nonerosive has raised the question of difference in the probable cellular and molecular mechanism between erosive and nonerosive forms. PMID:23798823

Radiofrequency currents exert cytotoxic effects in NB69 human neuroblastoma cells but not in peripheral blood mononuclear cells

PubMed Central

HERNÁNDEZ-BULE, MARÍA LUISA; ROLDÁN, ERNESTO; MATILLA, JOAQUÍN; TRILLO, MARÍA ÁNGELES; ÚBEDA, ALEJANDRO

2012-01-01

Recently, a number of electric and electrothermal therapies have been applied to the treatment of specific cancer types. However, the cellular and molecular mechanisms involved in the response to such therapies have not been well characterized yet. Capacitive-resistive electric transfer (CRET) therapy uses electric currents at frequencies within the 0.45–0.6 MHz range to induce hyperthermia in target tissues. Preliminary trials in cancer patients have shown consistent signs that CRET could slow down growth of tumor tissues in brain gliomas, without inducing detectable damage in the surrounding healthy tissue. Previous studies by our group have shown that subthermal treatment with 0.57-MHz electric currents can induce a cytostatic, not cytotoxic response in HepG2 human hepatocarcinoma cells; such effect being mediated by cell cycle alterations. In contrast, the study of the response of NB69 human neuroblastoma cells to the same electric treatment revealed consistent indications of cytotoxic effects. The present study extends the knowledge on the response of NB69 cells to the subthermal stimulus, comparing it to that of primary cultures of human peripheral blood mononuclear cells (PBMC) exposed to the same treatment. The results showed no sensitivity of PBMC to the 0.57 MHz subthermal currents and confirmed that the treatment exerts a cytotoxic action in NB69 cells. The data also revealed a previously undetected cytostatic response of the neuroblastoma cell line. CRET currents affected NB69 cell proliferation by significantly reducing the fraction of cells in the phase G2/M of the cell cycle at 12 h of exposure. These data provide new information on the mechanisms of response to CRET therapy, and are consistent with a cytotoxic and/or cytostatic action of the electric treatment, which would affect human cells of tumor origin but not normal cells with a low proliferation rate. PMID:22843038

Radiofrequency currents exert cytotoxic effects in NB69 human neuroblastoma cells but not in peripheral blood mononuclear cells.

PubMed

Hernández-Bule, María Luisa; Roldán, Ernesto; Matilla, Joaquín; Trillo, María Angeles; Ubeda, Alejandro

2012-10-01

Recently, a number of electric and electrothermal therapies have been applied to the treatment of specific cancer types. However, the cellular and molecular mechanisms involved in the response to such therapies have not been well characterized yet. Capacitive-resistive electric transfer (CRET) therapy uses electric currents at frequencies within the 0.45-0.6 MHz range to induce hyperthermia in target tissues. Preliminary trials in cancer patients have shown consistent signs that CRET could slow down growth of tumor tissues in brain gliomas, without inducing detectable damage in the surrounding healthy tissue. Previous studies by our group have shown that subthermal treatment with 0.57-MHz electric currents can induce a cytostatic, not cytotoxic response in HepG2 human hepatocarcinoma cells; such effect being mediated by cell cycle alterations. In contrast, the study of the response of NB69 human neuroblastoma cells to the same electric treatment revealed consistent indications of cytotoxic effects. The present study extends the knowledge on the response of NB69 cells to the subthermal stimulus, comparing it to that of primary cultures of human peripheral blood mononuclear cells (PBMC) exposed to the same treatment. The results showed no sensitivity of PBMC to the 0.57 MHz subthermal currents and confirmed that the treatment exerts a cytotoxic action in NB69 cells. The data also revealed a previously undetected cytostatic response of the neuroblastoma cell line. CRET currents affected NB69 cell proliferation by significantly reducing the fraction of cells in the phase G2/M of the cell cycle at 12 h of exposure. These data provide new information on the mechanisms of response to CRET therapy, and are consistent with a cytotoxic and/or cytostatic action of the electric treatment, which would affect human cells of tumor origin but not normal cells with a low proliferation rate.

Synergistic Effect of Transient Receptor Potential Antagonist and Amiloride against Maitotoxin Induced Calcium Increase and Cytotoxicity in Human Neuronal Stem Cells.

PubMed

Boente-Juncal, Andrea; Vale, Carmen; Alfonso, Amparo; Botana, Luis M

2018-05-16

Maitotoxins (MTX) are among the most potent marine toxins identified to date causing cell death trough massive calcium influx. However, the exact mechanism for the MTX-induced calcium entry and cytotoxicity is still unknown. In this work, the effect of MTX-1 on the cytosolic free calcium concentration and cellular viability of human neuronal stem cells was evaluated. MTX elicited a concentration-dependent decrease in cell viability which was already evident after 1 h of treatment with 0.25 nM MTX; however, at a concentration of 0.1 nM, the toxin did not cause cell death even after 14 days of exposure. Moreover, the toxin caused a concentration dependent rise in the cytosolic calcium concentration which was maximal at toxin concentrations of 1 nM and dependent on the presence of extracellular calcium on the bathing solution. Several pharmacological approaches were employed to evaluate the role of canonical transient potential receptor channels (TRPC) on the MTX effects. The results presented here lead to the identification of the TRPC4 channels as contributors to the MTX effects in human neuronal cells. Both, the calcium increase and the cytotoxicity of MTX were either fully (for the calcium increase) or partially (in the case of cytotoxicity) reverted by the blockade of canonical TRPC4 receptors with the selective antagonist ML204. Furthermore, the sodium proton exchanger blocker amiloride also partially inhibited the calcium rise and the cell death elicited by MTX while the combination of amiloride and ML204 fully prevented both the cytotoxicity and the calcium rise elicited by the toxin.

[Ultrastructural changes of human dental hard tissues during orthodontic treatment with fixed appliances].

PubMed

Antonova, I N; Goncharov, V D; Bobrova, E A

The aim of the study was to evaluate ultrastructural changes of dental enamel after fixation of orthodontic appliances, initial influence of orthodontic forces and removal of braces. Five intact permanent tooth extracted for orthodontic reasons were included in the experimental study. Scanning probe microscopy was conducted in 4 random enamel points in each tooth (20 points overall) in semi-contact mode with standard 10 nm probes. The study showed ultrastructural enamel changes such as nanofractures up to 1 mm along the braces locks. The changes correlated with surface morphological features and teeth anatomy and may play an important role in dental decay and non-carious lesions occurring in the course of orthodontic treatment.

Cytotoxicity of protein corona-graphene oxide nanoribbons on human epithelial cells

NASA Astrophysics Data System (ADS)

Mbeh, Doris A.; Akhavan, Omid; Javanbakht, Taraneh; Mahmoudi, Morteza; Yahia, L.'Hocine

2014-11-01

Graphene oxide nanoribbons (GONRs) were synthesized using an oxidative unzipping of multi-walled carbon nanotubes. The interactions of the GONRs with various concentrations of fetal bovine serum or human plasma serum indicated that the GONRs were functionalized substantially by the albumin originated from the two different protein sources. Then, concentration-dependent cytotoxicity of the protein-functionalized GONRs on human epithelial cells was studied. Although the GONRs with concentrations ≤50 μg/mL did not exhibit significant cytotoxicity on the cells (with the cell viability >85%), the concentration of 100 μg/mL exhibited significant cytotoxicity including prevention of cell proliferation and induction of cell apoptosis. These results can provide more in-depth understanding about cytotoxic effects of graphene nanostructures which can be functionalized by the proteins of media.

Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids

PubMed Central

Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

2015-01-01

Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern

Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids.

PubMed

Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

2015-11-01

Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern

Loss of Sleep Affects the Ultrastructure of Pyramidal Neurons in the Adolescent Mouse Frontal Cortex

PubMed Central

de Vivo, Luisa; Nelson, Aaron B.; Bellesi, Michele; Noguti, Juliana; Tononi, Giulio; Cirelli, Chiara

2016-01-01

Study Objective: The adolescent brain may be uniquely affected by acute sleep deprivation (ASD) and chronic sleep restriction (CSR), but direct evidence is lacking. We used electron microscopy to examine how ASD and CSR affect pyramidal neurons in the frontal cortex of adolescent mice, focusing on mitochondria, endosomes, and lysosomes that together perform most basic cellular functions, from nutrient intake to prevention of cellular stress. Methods: Adolescent (1-mo-old) mice slept (S) or were sleep deprived (ASD, with novel objects and running wheels) during the first 6–8 h of the light period, chronically sleep restricted (CSR) for > 4 days (using novel objects, running wheels, social interaction, forced locomotion, caffeinated water), or allowed to recover sleep (RS) for ∼32 h after CSR. Ultrastructural analysis of 350 pyramidal neurons was performed (S = 82; ASD = 86; CSR = 103; RS = 79; 4 to 5 mice/group). Results: Several ultrastructural parameters differed in S versus ASD, S versus CSR, CSR versus RS, and S versus RS, although the different methods used to enforce wake may have contributed to some of the differences between short and long sleep loss. Differences included larger cytoplasmic area occupied by mitochondria in CSR versus S, and higher number of secondary lysosomes in CSR versus S and RS. We also found that sleep loss may unmask interindividual differences not obvious during baseline sleep. Moreover, using a combination of 11 ultrastructural parameters, we could predict in up to 80% of cases whether sleep or wake occurred at the single cell level. Conclusions: Ultrastructural analysis may be a powerful tool to identify which cellular organelles, and thus which cellular functions, are most affected by sleep and sleep loss. Citation: de Vivo L, Nelson AB, Bellesi M, Noguti J, Tononi G, Cirelli C. Loss of sleep affects the ultrastructure of pyramidal neurons in the adolescent mouse frontal cortex. SLEEP 2016;39(4):861–874. PMID:26715225

Comparative Phytochemical Analysis of Essential Oils from Different Biological Parts of Artemisia herba alba and Their Cytotoxic Effect on Cancer Cells

PubMed Central

Tilaoui, Mounir; Ait Mouse, Hassan; Jaafari, Abdeslam; Zyad, Abdelmajid