Sample records for cell surface extracts
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Rahim, Zubaidah Haji Abdul; Thurairajah, Nalina
2011-04-01
Previous studies have shown that Piper betle L. leaves extract inhibits the adherence of Streptococcus mutans to glass surface, suggesting its potential role in controlling dental plaque development. In this study, the effect of the Piper betle L. extract towards S. mutans (with/without sucrose) using scanning electron microscopy (SEM) and on partially purified cell-associated glucosyltransferase activity were determined. S. mutans were allowed to adhere to glass beads suspended in 6 different Brain Heart Infusion broths [without sucrose; with sucrose; without sucrose containing the extract (2 mg mL(-1) and 4 mg mL(-1)); with sucrose containing the extract (2 mg mL(-1) and 4 mg mL(-1))]. Positive control was 0.12% chlorhexidine. The glass beads were later processed for SEM viewing. Cell surface area and appearance and, cell population of S. mutans adhering to the glass beads were determined upon viewing using the SEM. The glucosyltransferase activity (with/without extract) was also determined. One- and two-way ANOVA were used accordingly. It was found that sucrose increased adherence and cell surface area of S. mutans (p<0.001). S. mutans adhering to 100 µm² glass surfaces (with/without sucrose) exhibited reduced cell surface area, fluffy extracellular appearance and cell population in the presence of the Piper betle L. leaves extract. It was also found that the extract inhibited glucosyltransferase activity and its inhibition at 2.5 mg mL(-1) corresponded to that of 0.12% chlorhexidine. At 4 mg mL(-1) of the extract, the glucosyltransferase activity was undetectable and despite that, bacterial cells still demonstrated adherence capacity. The SEM analysis confirmed the inhibitory effects of the Piper betle L. leaves extract towards cell adherence, cell growth and extracellular polysaccharide formation of S. mutans visually. In bacterial cell adherence, other factors besides glucosyltransferase are involved.
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RAHIM, Zubaidah Haji Abdul; THURAIRAJAH, Nalina
2011-01-01
Introduction Previous studies have shown that Piper betle L. leaves extract inhibits the adherence of Streptococcus mutans to glass surface, suggesting its potential role in controlling dental plaque development. Objectives: In this study, the effect of the Piper betle L. extract towards S. mutans (with/without sucrose) using scanning electron microscopy (SEM) and on partially purified cell-associated glucosyltransferase activity were determined. Material and Methods S. mutans were allowed to adhere to glass beads suspended in 6 different Brain Heart Infusion broths [without sucrose; with sucrose; without sucrose containing the extract (2 mg mL-1 and 4 mg mL-1); with sucrose containing the extract (2 mg mL-1 and 4 mg mL-1)]. Positive control was 0.12% chlorhexidine. The glass beads were later processed for SEM viewing. Cell surface area and appearance and, cell population of S. mutans adhering to the glass beads were determined upon viewing using the SEM. The glucosyltransferase activity (with/without extract) was also determined. One- and two-way ANOVA were used accordingly. Results It was found that sucrose increased adherence and cell surface area of S. mutans (p<0.001). S. mutans adhering to 100 µm2 glass surfaces (with/without sucrose) exhibited reduced cell surface area, fluffy extracellular appearance and cell population in the presence of the Piper betle L. leaves extract. It was also found that the extract inhibited glucosyltransferase activity and its inhibition at 2.5 mg mL-1 corresponded to that of 0.12% chlorhexidine. At 4 mg mL-1 of the extract, the glucosyltransferase activity was undetectable and despite that, bacterial cells still demonstrated adherence capacity. Conclusion The SEM analysis confirmed the inhibitory effects of the Piper betle L. leaves extract towards cell adherence, cell growth and extracellular polysaccharide formation of S. mutans visually. In bacterial cell adherence, other factors besides glucosyltransferase are involved. PMID:21552715
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Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn; Shin, Myeong Heon
2007-10-01
The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-kappaB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-kappaB and JNK.
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Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn
2007-01-01
The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-κB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-κB and JNK. PMID:17982228
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Wang, Yi; Lee, Sui M; Dykes, Gary A
2013-01-01
Tea can inhibit the attachment of Streptococcus mutans to surfaces and subsequent biofilm formation. Five commercial tea extracts were screened for their ability to inhibit attachment and biofilm formation by two strains of S. mutans on glass and hydroxyapatite surfaces. The mechanisms of these effects were investigated using scanning electron microscopy (SEM) and phytochemical screening. The results indicated that extracts of oolong tea most effectively inhibited attachment and extracts of pu-erh tea most effectively inhibited biofilm formation. SEM images showed that the S. mutans cells treated with extracts of oolong tea, or grown in medium containing extracts of pu-erh tea, were coated with tea components and were larger with more rounded shapes. The coatings on the cells consisted of flavonoids, tannins and indolic compounds. The ratio of tannins to simple phenolics in each of the coating samples was ∼3:1. This study suggests potential mechanisms by which tea components may inhibit the attachment and subsequent biofilm formation of S. mutans on tooth surfaces, such as modification of cell surface properties and blocking of the activity of proteins and the structures used by the bacteria to interact with surfaces.
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Razak, Fathilah Abdul; Othman, Rofina Yasmin; Rahim, Zubaidah Haji Abd
2006-06-01
The adhesion of early settlers of dental plaque to the tooth surface has a role in the initiation of the development of dental plaque. The hydrophobic surface properties of the bacteria cell wall are indirectly responsible for the adhesion of the bacteria cell to the acquired pellicle on the tooth surfaces. In this study, the effect of aqueous extract of two plants (Psidium guajava and Piper betle) on the cell-surface hydro-phobicity of early settlers of dental plaque was determined in vitro. Hexadecane, a hydrocarbon was used to represent the hydrophobic surface of the teeth in the oral cavity. It was found that treatment of the early plaque settlers with 1 mg/ml extract of Psidium guajava reduced the cell-surface hydrophobicity of Strep. sanguinis, Strep. mitis and Actinomyces sp. by 54.1%, 49.9% and 40.6%, respectively. Treatment of these bacteria with the same concentration of Piper betle however, showed a comparatively lesser effect (< 10%). It was also observed that the anti-adhesive effect of the two extracts on the binding of the early plaque settlers to hexadecane is concentration dependent.
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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.
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Klančnik, A; Šikić Pogačar, M; Trošt, K; Tušek Žnidarič, M; Mozetič Vodopivec, B; Smole Možina, S
2017-01-01
To define anti-Campylobacter jejuni activity of an extract from waste skins and seeds of Pinot noir grapes (GSS), resveratrol and possible resistance mechanisms, and the influence of these on Camp. jejuni morphology. Using gene-specific knock-out Camp. jejuni mutants and an efflux pump inhibitor, we showed CmeABC as the most active efflux pump for extrusion across the outer membrane of GSS extract and resveratrol. Using polystyrene surface and pig small intestine epithelial (PSI) and human foetal small intestine (H4) cell lines, GSS extract shows an efficient inhibition of adhesion of Camp. jejuni to these abiotic and biotic surfaces. Low doses of GSS extract can inhibit Camp. jejuni adhesion to polystyrene surfaces and to PSI and H4 cells, and can thus modulate Camp. jejuni invasion and intracellular survival. An understanding of the activities of GSS extract and resveratrol as bacterial growth inhibitors and the specific mechanisms of cell accumulation is crucial for our understanding of Camp. jejuni resistance. GSS extract inhibition of Camp. jejuni adhesion to abiotic and biotic surfaces provides a further step towards the application of new innovative strategies to control Campylobacter contamination and infection via the food chain. © 2016 The Society for Applied Microbiology.
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Qi, Aisha; Yeo, Leslie; Friend, James; Ho, Jenny
2010-02-21
Paper has been proposed as an inexpensive and versatile carrier for microfluidics devices with abilities well beyond simple capillary action for pregnancy tests and the like. Unlike standard microfluidics devices, extracting a fluid from the paper is a challenge and a drawback to its broader use. Here, we extract fluid from narrow paper strips using surface acoustic wave (SAW) irradiation that subsequently atomizes the extracted fluid into a monodisperse aerosol for use in mass spectroscopy, medical diagnostics, and drug delivery applications. Two protein molecules, ovalbumin and bovine serum albumin (BSA), have been preserved in paper and then extracted using atomized mist through SAW excitation; protein electrophoresis shows there is less than 1% degradation of either protein molecule in this process. Finally, a solution of live yeast cells was infused into paper, which was subsequently dried for preservation then remoistened to extract the cells via SAW atomization, yielding live cells at the completion of the process. The successful preservation and extraction of fluids, proteins and yeast cells significantly expands the usefulness of paper in microfluidics.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Dhere, N.G.; Wollam, M.E.; Gadre, K.S.
1997-12-31
Silicon solar cell/EVA composite is being studied with an objective to further improve the manufacturing technology of PV modules. Sample extraction and adhesion strength measurement process has been modified. Silicon and EVA samples were extracted from solar cells of new and field-deployed modules. Optical microscopy, SEM, and AES of samples from new modules revealed EVA islands covering most of the silicon cell surface indicating a cohesive failure. A good correlation was observed between the adhesive strength and surface concentration of carbon. A low carbon concentration which indicated less EVA clinging to cell surface always resulted in low adhesive strengths. Themore » correlation provides a simple technique for inferring properties of EVA.« less
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NASA Astrophysics Data System (ADS)
Jiao, Jiajia; Sun, Lili; Guo, Zaiyu; Hou, Sen; Holyst, Robert; Lu, Yun; Feng, Xizeng
2016-12-01
Polydimethylsiloxane (PDMS) is widely used as a cell culture platform to produce micro- and nano-technology based microdevices. However, the native PDMS surface is not suitable for cell adhesion and is always subject to bacterial pollution and cancer cell invasion. Coating the PDMS surface with antibacterial or anticancer materials often causes considerable harm to the non-cancer mammalian cells on it. We have developed a method to fabricate a biocompatible PDMS surface which not only promotes non-cancer mammalian cell growth but also has antibacterial and anticancer activities, by coating the PDMS surface with a Chinese herb extract, paeonol. Coating changes the wettability and the elemental composition of the PDMS surface. Molecular dynamic simulation indicates that the absorption of paeonol onto the PDMS surface is an energy favourable process. The paeonol-coated PDMS surface exhibits good antibacterial activity against both Gram-positive and Gram-negative bacteria. Moreover considerable antibacterial activity is maintained after the coated surface is rinsed or incubated in water. The coated PDMS surface inhibits bacterial growth on the contact surface and promotes non-cancer mammalian cell growth with low cell toxicity; meanwhile the growth of cancer cells is significantly inhibited. Our study will potentially guide PDMS surface modification approaches to produce biomedical devices.
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Relationship of wood surface energy to surface composition
Feipeng P. Liu; Timothy G. Rials; John Simonsen
1998-01-01
The wood cell wall is composed of cellulose, lignin, hemicelluloses, and extractives. Thus, the surface energy of the wood material must be some combination of the surface energies of these components. The influence of extractives on wood surface chemistry can be important in diverse industrial applications, such as coating, pulping, and wood-based composites. In this...
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Dudzinska, Dominika; Luzak, Boguslawa; Boncler, Magdalena; Rywaniak, Joanna; Sosnowska, Dorota; Podsedek, Anna; Watala, Cezary
2014-09-01
Many experimental studies have demonstrated the favorable biological activities of plants belonging to the genus Rubus, but little is known of the role of Rubus leaf extracts in the modulation of the surface membrane expression and activity of endothelial apyrase. The aim of this study was to assess the influence of 1-15 μg/ml Rubus extracts on CD39 expression and enzymatic activity, and on the activation (ICAM-1 expression) and viability of human umbilical vein endothelial cells (HUVEC). The polyphenolic contents and antioxidative capacities of extracts from dewberry (R. caesius L.) and raspberry (R. idaeus L.) leaves were also investigated. The techniques applied were flow cytometry (endothelial surface membrane expression of ICAM-1 and CD39), malachite green assay (CD39 activity), HPLC-DAD (quantitative analysis of polyphenolic extract), ABTS, DPPH and FRAP spectrometric assays (antioxidant capacity), and the MTT test (cell viability). Significantly increased CD39 expressions and significantly decreased ATPDase activities were found in the cells treated with 15 μg/ml of either extract compared to the results for the controls. Neither of the extracts affected cell proliferation, but both significantly augmented endothelial cell ICAM-1 expression. The overall antioxidant capacities of the examined extracts remained relatively high and corresponded well to the determined total polyphenol contents. Overall, the results indicate that under in vitro conditions dewberry and raspberry leaf extracts have unfavorable impact on endothelial cells.
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Behzad, F; Jones, C J; Ball, S; Alvares, T; Aplin, J D
1995-01-01
A method is described for the sequential detergent and high ionic strength extraction of human amnion with the progressive enrichment of the intermediate filament (IF) cytoskeleton and its associated structures including hemidesmosomes (HD). TEM of the extracted epithelium in situ reveals IF bundles beneath the apical cell surface, around the nucleus and at the lateral edges of the cells where association with desmosomes occurs. IF bundles are also very prominent within basal cell processes where they loop through the cytoplasm adjacent to the HDs. A novel connecting filament network is observed running between the IFs and the hemidesmosomal dense plaque. The adjacent IF network contains both cytokeratin and vimentin, the latter revealed much more fully as a result of the extraction protocol. The hemidesmosomal plasma membrane contains integrin subunits alpha 6 and beta 4 and these are quantitatively retained as the basal cell surface during extraction, while nonjunctional plasma membrane is solubilised. Integrin beta 1 is found at the basolateral cell surface but, like actin, is extracted quantitatively and is not present in HDs. The extracted epithelial cells may be recovered by scraping and the IF network depolymerised to produce a particulate fraction containing short residual IFs, associated thin filaments and plaque material. This fraction contains immunoreactive cytokeratin and vimentin. Integrin alpha 6 beta 4 has been used as a biochemical criterion of the presence of HD material in the fraction. Both subunits are highly enriched. The fraction also contains the hemidesmosomal components HD1, BP230 and BP180. This method is likely to be useful in further characterisation of the HD.
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Habtemariam, S
1998-05-01
Treatment of human endothelial cells with cytokines such as tumour necrosis factor-alpha (TNF) or E. coli lipopolysaccharide (LPS) induces the expression of several adhesion molecules and enhances leukocyte adhesion to endothelial cell surface. Interfering with this leukocyte adhesion or adhesion molecules upregulation is an important therapeutic target for the treatment of bacterial sepsis and various inflammatory diseases. In the course of screening marketed European anti-inflammatory herbal drugs for TNF antagonistic activity, a crude ethanolic extract of corn silk (stigma of Zea mays) exhibited significant activity. The extract at concentrations of 9-250 micrograms/ml effectively inhibited the TNF- and LPS-induced adhesiveness of EAhy 926 endothelial cells to monocytic U937 cells. Similar concentration ranges of corn silk extract did also block the TNF and LPS but not the phorbol 12-myristate 13-acetate-induced ICAM-1 expression on EAhy 926 endothelial cell surface. The extract did not alter the production of TNF by LPS-activated macrophages and failed to inhibit the cytotoxic activity of TNF. It is concluded that corn silk possesses important therapeutic potential for TNF- and LPS-mediated leukocyte adhesion and trafficking.
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MPN estimation of qPCR target sequence recoveries from whole cell calibrator samples
DNA extracts from enumerated target organism cells (calibrator samples) have been used for estimating Enterococcus cell equivalent densities in surface waters by a comparative cycle threshold (Ct) qPCR analysis method. To compare surface water Enterococcus density estimates from ...
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Fabrication of orderly nanostructured PLGA scaffolds using anodic aluminum oxide templates.
Wang, Gou-Jen; Lin, Yan-Cheng; Li, Ching-Wen; Hsueh, Cheng-Chih; Hsu, Shan-Hui; Hung, Huey-Shan
2009-08-01
In this research, two simple fabrication methods to fabricate orderly nanostructured PLGA scaffolds using anodic aluminum oxide (AAO) template were conducted. In the vacuum air-extraction approach, the PLGA solution was cast on an AAO template first. The vacuum air-extraction process was then applied to suck the semi-congealed PLGA into the nanopores of the AAO template to form a bamboo sprouts array of PLGA. The surface roughness of the nanostructured scaffolds, ranging from 20 nm to 76 nm, can be controlled by the sucking time of the vacuum air-extraction process. In the replica molding approach, the PLGA solution was cast on the orderly scraggy barrier-layer surface of an AAO membrane to fabricate a PLGA scaffold of concave nanostructure. Cell culture experiments using the bovine endothelial cells (BEC) demonstrated that the nanostructured PLGA membrane can increase the cell growing rate, especially for the bamboo sprouts array scaffolds with smaller surface roughness.
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Biofilm formation by Salmonella spp. in catfish mucus extract under industrial conditions.
Dhowlaghar, Nitin; De Abrew Abeysundara, Piumi; Nannapaneni, Ramakrishna; Schilling, Mark W; Chang, Sam; Cheng, Wen-Hsing; Sharma, Chander S
2018-04-01
The objective of this study was to determine the effect of strain and temperature on the growth and biofilm formation of Salmonella spp. in high and low concentrations of catfish mucus extract on different food-contact surfaces at 22 °C and 10 °C. The second objective of this study was to evaluate the efficacy of disinfectants at recommended concentrations and contact times for removing Salmonella biofilms cells on a stainless steel surface containing catfish mucus extract. Growth and biofilm formation of all Salmonella strains increased with higher concentrations of catfish mucus extract at both 10 °C and 22 °C. In 15 μg/ml of catfish mucus extract inoculated with 3 log CFU/ml, the biofilm levels of Salmonella on stainless steel surface reached to 3.5 log CFU/cm 2 at 10 °C or 5.5 log CFU/cm 2 at 22 °C in 7 days. In 375 μg/ml of catfish mucus extract inoculated with 3 log CFU/ml, the biofilm levels of Salmonella on the stainless steel surface reached 4.5 log CFU/cm 2 at 10 °C and 6.5 log CFU/cm 2 at 22 °C in 7 days. No differences were observed between Salmonella strains tested for biofilm formation in catfish mucus extract on the stainless steel surface. The biofilm formation by Salmonella Blockley (7175) in catfish mucus extract was less (P < 0.05) on buna-N rubber when compared to stainless steel, polyethylene and polyurethane surfaces. Salmonella biofilm cells were not detectable on the stainless steel surface after treatment with a mixture of disinfectants but were still present when single compound disinfectants were used. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Pacholak, A; Simlat, J; Zgoła-Grześkowiak, A; Kaczorek, E
2018-06-20
Azole fungicides constitute an extensive group of potential emerging pollutants which can be found in natural environment. This study focuses on the biodegradation of clotrimazole and the characterization of cell surface properties of microorganisms capable of degradation of this compound. The influence of long-term contact of bacteria with clotrimazole and the impact of the addition of Saponaria officinalis extract on cell surface modification was also checked. The biodegradation of clotrimazole did not exceed 70%. The presence of plant extract increased biodegradation of fungicide. The cells metabolic activity after one-month exposure to clotrimazole was the highest for each tested strain. Moreover, metabolic stress led to a strong modification of cell surface properties. The results are promising for determining the impact of clotrimazole on environmental microorganisms. Copyright © 2018 Elsevier Inc. All rights reserved.
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Sheoran, Sunita; Panda, Bibhu Prasad; Admane, Prasad S; Panda, Amulya Kumar; Wajid, Saima
2015-01-01
Gymnema sylvestre is an important anti-diabetic medicinal plant, hence it is necessary to study the effective extraction of its active medicinal components. To develop an efficient ultrasound-assisted extraction method for anti-diabetic gymnemic acids from Gymnema sylvestre leaves and measure their effect on insulin-producing RINm-5 F β cells. Box-Behnken's design and response surface methodology was applied to the ultrasound-assisted extraction of gymnemic acids from Gymnema sylvestre leaves. Analysis of gymnemic acids was carried out by high-performance thin-layer chromatography by converting total gymnemic acids into gymnemagenin by alkali hydrolysis. Effects of extracts on insulin production were tested on cultured, insulin-producing RINm-5 F β cell lines. The point prediction tool of the design expert software predicted 397.9 mg gymnemic acids per gram of the defatted G. sylvestre leaves using ultrasound-assisted extraction, with ethanol at 60 °C for 30 min. The predicted condition shows 93.34% validity under experimental conditions. The ultrasound-assisted extract caused up to about four times more insulin production from RINm-5 F β cells than extracts obtained from Soxhlet extraction. Response surface methodology was successfully used to improve the extraction of gymnemic acids from G. sylvestre leaves. The ultrasound-assisted extraction process may be a better alternative to prepare such herbal extracts because it saves time and may prevent excess degradation of the target analytes. Copyright © 2014 John Wiley & Sons, Ltd.
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Ghasemzadeh, Ali; Jaafar, Hawa Z E; Rahmat, Asmah
2015-07-30
Analysis and extraction of plant matrices are important processes for the development, modernization, and quality control of herbal formulations. Response surface methodology is a collection of statistical and mathematical techniques that are used to optimize the range of variables in various experimental processes to reduce the number of experimental runs, cost , and time, compared to other methods. Response surface methodology was applied for optimizing reflux extraction conditions for achieving high 6-gingerol and 6-shogaol contents, and high antioxidant activity in Zingiber officinale var. rubrum Theilade . The two-factor central composite design was employed to determine the effects of two independent variables, namely extraction temperature (X1: 50-80 °C) and time (X2: 2-4 h), on the properties of the extracts. The 6-gingerol and 6-shogaol contents were measured using ultra-performance liquid chromatography. The antioxidant activity of the rhizome extracts was determined by means of the 1,1-diphenyl-2-picrylhydrazyl assay. Anticancer activity of optimized extracts against HeLa cancer cell lines was measured using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Increasing the extraction temperature and time induced significant response of the variables. The optimum extraction condition for all responses was at 76.9 °C for 3.4 h. Under the optimum condition, the corresponding predicted response values for 6-gingerol, 6-shogaol, and the antioxidant activity were 2.89 mg/g DW, 1.85 mg/g DW, and 84.3%, respectively. 6-gingerol and 6-shogaol were extracted under optimized condition to check the viability of the models. The values were 2.92 and 1.88 mg/g DW, and 84.0% for 6-gingerol, 6-shogaol, and the antioxidant activity respectively. The experimental values agreed with those predicted, thus indicating suitability of the models employed and the success of RSM in optimizing the extraction condition. With optimizing of reflux extraction anticancer activity of extracts against HeLa cancer cells enhanced about 16.8%. The half inhibition concentration (IC50) value of optimized and unoptimized extract was found at concentration of 20.9 and 38.4 μg/mL respectively. Optimized extract showed more distinct anticancer activities against HeLa cancer cells in a concentration of 40 μg/mL (P < 0.01) without toxicity to normal cells. The results indicated that the pharmaceutical quality of ginger could be improved significantly by optimizing of extraction process using response surface methodology.
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Holt, P G; Robinson, B W; Reid, M; Kees, U R; Warton, A; Dawson, V H; Rose, A; Schon-Hegrad, M; Papadimitriou, J M
1986-01-01
The inflammatory and immune cell populations of the human lung parenchyma have not been characterized in detail. This report describes a novel and efficient procedure for their extraction. Histologically normal human lung tissue samples from pneumonectomy specimens were sliced to 0.5 mm, and digested in collagenase/DNAse. Viable mononuclear cell yields ranged from 15-48 X 10(6)/g, and were markedly in excess of reported methods employing mechanical tissue disruption, which normally yield populations containing almost exclusively macrophages. The lung digest population was examined by flow cytometry using monoclonal antibodies against cell surface receptors, and found to comprise up to 40% T lymphocytes, 10% B lymphocytes and 30% macrophages, contaminated by less than 1% peripheral blood cells. Based upon these figures, the recoverable lung parenchymal lymphoid cell pool appears considerably larger than previously recognized, being of the same order as the peripheral blood pool. Initial functional studies suggest that such cellular activities as antigen-specific T cell proliferation, antigen-presentation, interleukin 1 production and natural killer cell activity survive the extraction process, and controlled enzymatic digestion experiments with peripheral blood cells indicate that the degree of enzyme-mediated damage to these functions and to cell-surface structures, was minimal. The extraction method thus appears suitable for studying the types and functions of human parenchymal lung cells in health and disease. Images Fig. 2 p195-a PMID:3026698
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Battle, Katrina N; Jackson, Joshua M; Witek, Małgorzata A; Hupert, Mateusz L; Hunsucker, Sally A; Armistead, Paul M; Soper, Steven A
2014-03-21
We present a novel microfluidic solid-phase extraction (μSPE) device for the affinity enrichment of biotinylated membrane proteins from whole cell lysates. The device offers features that address challenges currently associated with the extraction and purification of membrane proteins from whole cell lysates, including the ability to release the enriched membrane protein fraction from the extraction surface so that they are available for downstream processing. The extraction bed was fabricated in PMMA using hot embossing and was comprised of 3600 micropillars. Activation of the PMMA micropillars by UV/O3 treatment permitted generation of surface-confined carboxylic acid groups and the covalent attachment of NeutrAvidin onto the μSPE device surfaces, which was used to affinity select biotinylated MCF-7 membrane proteins directly from whole cell lysates. The inclusion of a disulfide linker within the biotin moiety permitted release of the isolated membrane proteins via DTT incubation. Very low levels (∼20 fmol) of membrane proteins could be isolated and recovered with ∼89% efficiency with a bed capacity of 1.7 pmol. Western blotting indicated no traces of cytosolic proteins in the membrane protein fraction as compared to significant contamination using a commercial detergent-based method. We highlight future avenues for enhanced extraction efficiency and increased dynamic range of the μSPE device using computational simulations of different micropillar geometries to guide future device designs.
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Garrido, Gabino; Blanco-Molina, Magdalena; Sancho, Rocío; Macho, Antonio; Delgado, René; Muñoz, Eduardo
2005-03-01
A commercial aqueous stem bark extract of Mangifera indica L. (Vimang) has been reported to have antiinflammatory, immunomodulatory and antioxidant activities. The molecular basis for these diverse properties is still unknown. This study shows that a stem bark extract of M. indica inhibits early and late events in T cell activation, including CD25 cell surface expression, progression to the S-phase of the cell cycle and proliferation in response to T cell receptor (TCR) stimulation. Moreover, the extract prevented TNFalpha-induced IkappaBalpha degradation and the binding of NF-kappaB to the DNA. This study may help to explain at the molecular level some of the biological activities attributed to the aqueous stem bark extract of M. indica (Vimang).
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Kim, Jae Kyeom; Lim, Ho-Jeong; Kim, Mi-So; Choi, Soo Jung; Kim, Mi-Jeong; Kim, Cho Rong; Shin, Dong-Hoon; Shin, Eui-Cheol
2016-01-01
Background: The central nervous system is easily damaged by oxidative stress due to high oxygen consumption and poor defensive capacity. Hence, multiple studies have demonstrated that inhibiting oxidative stress-induced damage, through an antioxidant-rich diet, might be a reasonable approach to prevent neurodegenerative disease. Objective: In the present study, response surface methodology was utilized to optimize the extraction for neuro-protective constituents of Camellia japonica byproducts. Materials and Methods: Rat pheochromocytoma cells were used to evaluate protective potential of Camellia japonica byproducts. Results: Optimum conditions were 33.84 min, 75.24%, and 75.82°C for time, ethanol concentration and temperature. Further, we demonstrated that major organic acid contents were significantly impacted by the extraction conditions, which may explain varying magnitude of protective potential between fractions. Conclusions: Given the paucity of information in regards to defatted C. japonica seed cake and their health promoting potential, our results herein provide interesting preliminary data for utilization of this byproduct from oil processing in both academic and industrial applications. SUMMARY Neuro-protective potential of C. japonica seed cake on cell viability was affected by extraction conditionsExtraction conditions effectively influenced on active constituents of C. japonica seed cakeBiological activity of C. japonica seed cake was optimized by the responsive surface methodology. Abbreviations used: GC-MS: Gas chromatography-mass spectrometer, MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, PC12 cells: Pheochromocytoma, RSM: Response surface methodology. PMID:27601847
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Jaszewska, Edyta; Kośmider, Anita; Kiss, Anna K; Naruszewicz, Marek
2009-09-23
Three extracts of defatted seeds of Oenothera paradoxa Hudziok, aqueous extract, 60% ethanolic extract, and 30% isopropanolic extract, differing by their total content of phenolic compounds and by their contents of individual polyphenols, were investigated in this study. The extracts exerted cytotoxic action on HTB-140 human skin melanoma cells. After 24 h of incubation, IC(50) values of 169.7 +/- 5.9 micog/mL, 72.4 +/- 3.8 microg/mL, and 155.3 +/- 6.3 microg/mL were obtained for HTB-140 cells with the aqueous extract, 60% ethanolic extract, and 30% isopropanolic extract at the tested concentrations (5-200 microg/mL), respectively, while IC(50) for normal fibroblast cells NHDFs was not attained. Moreover, for HTB-140 cells, LD(50) (concentration at which 50% of cells were dead) of 89.2 +/- 4.3 microg/mL and 181.4 +/- 6.5 microg/mL were obtained with 60% ethanolic extract and 30% isopropanolic extract, respectively. In melanoma cells, all three extracts caused a concentration-dependent increase of ROS production, GSH, and ATP lowering, and appearance of phosphatidylserine on the external surface of cellular membranes where it was bound to annexin V-FITC; furthermore, apoptosis without activation of caspase-3 took place. The most effective was 60% ethanolic extract, which had the greatest total content of phenolic compounds and the greatest content of pentagalloyloglucose (PGG).
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Ren, Song; Wu, Ming; Guo, Jiayu; Zhang, Wang; Liu, Xiaohan; Sun, Lili; Holyst, Robert; Hou, Sen; Fang, Yongchun; Feng, Xizeng
2015-01-01
Coating of polydimethylsiloxane (PDMS) surface with a traditional Chinese herb extract chlorogenic acid (CA) solves the contemporary problem of sterilization of PDMS surface. The E. coli grows slower and has a higher death rate on the CA-coated PDMS surfaces. A smoother morphology of these E. coli cell wall is observed by atomic force microscopy (AFM). Unlike the reported mechanism, where CA inhibits bacterial growth by damaging the cell membrane in the bulk solution, we find the CA-coated PDMS surface also decreases the stiffness of the cell wall. A decrease in the Young’s modulus of the cell wall from 3 to 0.8 MPa is reported. Unexpectedly, the CA effect on the swarming ability and the biofilm stability of the bacteria can be still observed, even after they have been removed from the CA environment, indicating a decrease in their resistance to antibiotics for a prolonged time. The CA-coated PDMS surface shows better antibiotic effect against three types of both Gram-positive and Gran-negative bacteria than the gentamicin-coated PDMS surface. Coating of CA on PDMS surface not only solves the problem of sterilization of PDMS surface, but also shines light on the application of Chinese traditional herbs in scientific research. PMID:25993914
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Ren, Song; Wu, Ming; Guo, Jiayu; Zhang, Wang; Liu, Xiaohan; Sun, Lili; Holyst, Robert; Hou, Sen; Fang, Yongchun; Feng, Xizeng
2015-05-21
Coating of polydimethylsiloxane (PDMS) surface with a traditional Chinese herb extract chlorogenic acid (CA) solves the contemporary problem of sterilization of PDMS surface. The E. coli grows slower and has a higher death rate on the CA-coated PDMS surfaces. A smoother morphology of these E. coli cell wall is observed by atomic force microscopy (AFM). Unlike the reported mechanism, where CA inhibits bacterial growth by damaging the cell membrane in the bulk solution, we find the CA-coated PDMS surface also decreases the stiffness of the cell wall. A decrease in the Young's modulus of the cell wall from 3 to 0.8 MPa is reported. Unexpectedly, the CA effect on the swarming ability and the biofilm stability of the bacteria can be still observed, even after they have been removed from the CA environment, indicating a decrease in their resistance to antibiotics for a prolonged time. The CA-coated PDMS surface shows better antibiotic effect against three types of both Gram-positive and Gran-negative bacteria than the gentamicin-coated PDMS surface. Coating of CA on PDMS surface not only solves the problem of sterilization of PDMS surface, but also shines light on the application of Chinese traditional herbs in scientific research.
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Effect of bleaching agent extracts on murine macrophages.
Fernandes, Aletéia M M; Vilela, Polyana G F; Valera, Marcia C; Bolay, Carola; Hiller, Karl Anton; Schweikl, Helmut; Schmalz, Gottfried
2018-05-01
The aim of this study was to evaluate the cytotoxicity and the influence of bleaching agents on immunologically cell surface antigens of murine macrophages in vitro. RAW 264.7 cells were exposed to bleaching gel extracts (40% hydrogen peroxide or 20% carbamide peroxide) and different H 2 O 2 concentrations after 1 and 24-h exposure periods and 1-h exposure and 23-h recovery. Tests were performed with and without N-acetyl cysteine (NAC) and buthionine sulfoximine (BSO). Cell viability was determined by MTT assay. The expression of surface markers CD14, CD40, and CD54 with and without LPS stimulation was detected by flow cytometry, while the production of TNF-α was measured by ELISA. Statistical analysis was performed using the Mann-Whitney U test (α = 0.05). Extracts of bleaching agents were cytotoxic for cells after a 1-h exposure; cells could not recover after 24 h. This effect can be mitigated by the antioxidant NAC and increased by BSO, an inhibitor of glutathione (GSH) synthesis. LPS stimulated expression of all surface markers and TNF-α production. Exposure to bleaching agent extracts and H 2 O 2 leads to a reduction of TNF-α, CD14, and CD40 expression, while the expression of CD54 was upregulated at non-cytotoxic concentrations. Whereas NAC reduced this effect, it was increased in the presence of BSO. Extracts of bleaching agents were irreversibly cytotoxic to macrophages after a 1-h exposure. Only the expression of CD54 was upregulated. The reactions are mediated by the non-enzymatic antioxidant GSH. The addition of an antioxidant can downregulate unfavorable effects of dental bleaching.
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Lin, Liang-Tzung; Lai, Ying-Jang; Wu, She-Ching; Hsu, Wei-Hsuan; Tai, Chen-Jei
2018-01-01
Cordycepin is one of the most crucial bioactive compounds produced by Cordyceps militaris and has exhibited antitumor activity in various cancers. However, industrial production of large amounts of cordycepin is difficult. The porcine liver is abundant in proteins, vitamins, and adenosine, and these ingredients may increase cordycepin production and bioconversion during C. militaris fermentation. We observed that porcine liver extracts increased cordycepin production. In addition, air supply (2 h/d) significantly increased the cordycepin level in surface liquid-cultured C. militaris after 14 days. Moreover, blue light light-emitting diode irradiation (16 h/d) increased cordycepin production. These findings indicated that these conditions are suitable for increasing cordycepin production. We used these conditions to obtain water extract from the mycelia of surface liquid-cultured C. militaris (WECM) and evaluated the anti-oral cancer activity of this extract in vitro and in vivo. The results revealed that WECM inhibited the cell viability of SCC-4 oral cancer cells and arrested the cell cycle in the G2/M phase. Oxidative stress and mitochondrial dysfunction (mitochondrial fission) were observed in SCC-4 cells treated with WECM for 12 hours. Furthermore, WECM reduced tumor formation in 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis through the downregulation of proliferating cell nuclear antigen, vascular endothelial growth factor, and c-fos expression. The results indicated that porcine liver extracts irradiated with blue light light-emitting diode and supplied with air can be used as a suitable medium for the growth of mycelia and production of cordycepin, which can be used in the treatment of oral cancer. Copyright © 2017. Published by Elsevier B.V.
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Shen, Simon; Syal, Karan; Tao, Nongjian; Wang, Shaopeng
2015-12-01
We present a Single-Cell Motion Characterization System (SiCMoCS) to automatically extract bacterial cell morphological features from microscope images and use those features to automatically classify cell motion for rod shaped motile bacterial cells. In some imaging based studies, bacteria cells need to be attached to the surface for time-lapse observation of cellular processes such as cell membrane-protein interactions and membrane elasticity. These studies often generate large volumes of images. Extracting accurate bacterial cell morphology features from these images is critical for quantitative assessment. Using SiCMoCS, we demonstrated simultaneous and automated motion tracking and classification of hundreds of individual cells in an image sequence of several hundred frames. This is a significant improvement from traditional manual and semi-automated approaches to segmenting bacterial cells based on empirical thresholds, and a first attempt to automatically classify bacterial motion types for motile rod shaped bacterial cells, which enables rapid and quantitative analysis of various types of bacterial motion.
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A Direct Cell Quenching Method for Cell-Culture Based Metabolomics
A crucial step in metabolomic analysis of cellular extracts is the cell quenching process. The conventional method first uses trypsin to detach cells from their growth surface. This inevitably changes the profile of cellular metabolites since the detachment of cells from the extr...
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Surface Acoustic Waves Grant Superior Spatial Control of Cells Embedded in Hydrogel Fibers.
Lata, James P; Guo, Feng; Guo, Jinshan; Huang, Po-Hsun; Yang, Jian; Huang, Tony Jun
2016-10-01
By exploiting surface acoustic waves and a coupling layer technique, cells are patterned within a photosensitive hydrogel fiber to mimic physiological cell arrangement in tissues. The aligned cell-polymer matrix is polymerized with short exposure to UV light and the fiber is extracted. These patterned cell fibers are manipulated into simple and complex architectures, demonstrating feasibility for tissue-engineering applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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NASA Astrophysics Data System (ADS)
Clark, W.; Dampier, F.; McDonald, R.; Lombardi, A.; Batson, D.
1985-02-01
The objectives of Part 1 of this program were to: (1) investigate reactions occurring in the Li/SOCl2 cell for a range of specified test conditions, and (2) to perform analyses to identify reactants, intermediates and products generated by the chemical and electrochemical reactions occuring in the cell and to assess their impact upon safety and performance. The stoichiometry of the SOCl2 reduction reaction was investigated in 0.6 Ahr prototype cells by extracting the cells five times with pure SOCl2, after discharge then analyzing the combined extracts for SO2 by quantitative IR spectroscopy. The cells had high electrolyte-to-carbon mass ratios comparable to those in commercial cells. The multiple SOCl2 extraction procedure was developed to recover the SO2 discharge product adsorbed on the high surface area carbon electrode.
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Triangle Geometry Processing for Surface Modeling and Cartesian Grid Generation
NASA Technical Reports Server (NTRS)
Aftosmis, Michael J. (Inventor); Melton, John E. (Inventor); Berger, Marsha J. (Inventor)
2002-01-01
Cartesian mesh generation is accomplished for component based geometries, by intersecting components subject to mesh generation to extract wetted surfaces with a geometry engine using adaptive precision arithmetic in a system which automatically breaks ties with respect to geometric degeneracies. During volume mesh generation, intersected surface triangulations are received to enable mesh generation with cell division of an initially coarse grid. The hexagonal cells are resolved, preserving the ability to directionally divide cells which are locally well aligned.
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Triangle geometry processing for surface modeling and cartesian grid generation
Aftosmis, Michael J [San Mateo, CA; Melton, John E [Hollister, CA; Berger, Marsha J [New York, NY
2002-09-03
Cartesian mesh generation is accomplished for component based geometries, by intersecting components subject to mesh generation to extract wetted surfaces with a geometry engine using adaptive precision arithmetic in a system which automatically breaks ties with respect to geometric degeneracies. During volume mesh generation, intersected surface triangulations are received to enable mesh generation with cell division of an initially coarse grid. The hexagonal cells are resolved, preserving the ability to directionally divide cells which are locally well aligned.
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Santos, Philipe; Aguiar, Ana C; Barbero, Gerardo F; Rezende, Camila A; Martínez, Julian
2015-01-01
Extracts from malagueta pepper (Capsicum frutescens L.) were obtained using supercritical fluid extraction (SFE) assisted by ultrasound, with carbon dioxide as solvent at 15MPa and 40°C. The SFE global yield increased up to 77% when ultrasound waves were applied, and the best condition of ultrasound-assisted extraction was ultrasound power of 360W applied during 60min. Four capsaicinoids were identified in the extracts and quantified by high performance liquid chromatography. The use of ultrasonic waves did not influence significantly the capsaicinoid profiles and the phenolic content of the extracts. However, ultrasound has enhanced the SFE rate. A model based on the broken and intact cell concept was adequate to represent the extraction kinetics and estimate the mass transfer coefficients, which were increased with ultrasound. Images obtained by field emission scanning electron microscopy showed that the action of ultrasonic waves did not cause cracks on the cell wall surface. On the other hand, ultrasound promoted disturbances in the vegetable matrix, leading to the release of extractable material on the solid surface. The effects of ultrasound were more significant on SFE from larger solid particles. Copyright © 2014 Elsevier B.V. All rights reserved.
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Turning the Moon into a Solar Photovoltaic Paradise
NASA Technical Reports Server (NTRS)
Freundlich, Alex; Alemu, Andenet; Williams, Lawrence; Nakamura, Takashi; Sibille, Laurent; Curren, Peter
2006-01-01
Lunar resource utilization has focused principally on the extraction of oxygen from the lunar regolith. A number of schemes have been proposed for oxygen extraction from Ilmenite and Anorthite. Serendipitously, these schemes have as their by-products (or more directly as their "waste products"), materials needed for the fabrication of thin film silicon solar cells. Thus lunar surface possesses both the elemental components needed for the fabrication of silicon solar cells and a vacuum environment that allows for vacuum deposition of thin film solar cells directly on the surface of the Moon without the need for vacuum chambers. In support of the US space exploration initiative a new architecture for the production of thin film solar cells on directly on the lunar surface is proposed. The paper discusses experimental data on the fabrication and properties of lunar glass substrates, evaporated lunar regolith thin films (anti-reflect coatings and insulators), and preliminary attempts in the fabrication of thin film (silicon/II-VI) photovoltaic materials on lunar regolith glass substrates. A conceptual design for a solar powered robotic rover capable of fabricating solar cells directly on the lunar surface is provided. Technical challenges in the development of such a facility and strategies to alleviate perceived difficulties are discussed.
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Dégbé, Mlatovi; Debierre-Grockiego, Françoise; Tété-Bénissan, Amivi; Débare, Héloïse; Aklikokou, Kodjo; Dimier-Poisson, Isabelle; Gbeassor, Messanvi
2018-01-01
Tectona grandis (teak) and Vernonia amygdalina (bitter leaf) are plants used in traditional medicine in West Africa. In this study, we tested ethanolic and hydro-ethanolic extracts of bark and leaves of T. grandis and ethanolic extract of leaves of V. amygdalina for their inhibitory effect on Toxoplasma gondii, a protozoan parasite responsible for toxoplasmosis. Ethanolic extract of V. amygdalina leaves had proportional contents of phenols, tannins, flavonoids, and polysaccharides. This extract presented the highest efficacy against T. gondii, the lowest cytotoxicity to mammalian cells, but moderate anti-oxidant activity compared to other plant extracts. Ethanolic extract of T. grandis bark also had elevated anti-T. gondii activity, low cytotoxicity on mammalian cells, and one of the highest anti-oxidant activities. However, the phytochemical content of this extract was not very different from the hydro-ethanolic extract, which had no anti-T. gondii activity. In addition, ethanolic extract of V. amygdalina leaves, but not of T. grandis bark, significantly increased the production of TNF-α and NO by antigen-presenting cells. Both extracts had the tendency to decrease expression of major histocompatibility complex molecules at the surface of antigen-presenting cells, while they did not modulate the percentage of apoptotic cells. A study of signalling pathways would help to determine the mechanisms of action of these plant extracts. © M. Dégbé et al., published by EDP Sciences, 2018.
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Enzymatic cell wall degradation of Chlorella vulgaris and other microalgae for biofuels production.
Gerken, Henri G; Donohoe, Bryon; Knoshaug, Eric P
2013-01-01
Cell walls of microalgae consist of a polysaccharide and glycoprotein matrix providing the cells with a formidable defense against its environment. We characterized enzymes that can digest the cell wall and weaken this defense for the purpose of protoplasting or lipid extraction. A growth inhibition screen demonstrated that chitinase, lysozyme, pectinase, sulfatase, β-glucuronidase, and laminarinase had the broadest effect across the various Chlorella strains tested and also inhibited Nannochloropsis and Nannochloris strains. Chlorella is typically most sensitive to chitinases and lysozymes, both enzymes that degrade polymers containing N-acetylglucosamine. Using a fluorescent DNA stain, we developed rapid methodology to quantify changes in permeability in response to enzyme digestion and found that treatment with lysozyme in conjunction with other enzymes has a drastic effect on cell permeability. Transmission electron microscopy of enzymatically treated Chlorella vulgaris indicates that lysozyme degrades the outer surface of the cell wall and removes hair-like fibers protruding from the surface, which differs from the activity of chitinase. This action on the outer surface of the cell causes visible protuberances on the cell surface and presumably leads to the increased settling rate when cells are treated with lysozyme. We demonstrate radical ultrastructural changes to the cell wall in response to treatment with various enzyme combinations which, in some cases, causes a greater than twofold increase in the thickness of the cell wall. The enzymes characterized in this study should prove useful in the engineering and extraction of oils from microalgae.
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Identification and characterization of Vibrio cholerae surface proteins by radioiodination.
Richardson, K; Parker, C D
1985-01-01
Whole cells and isolated outer membrane from Vibrio cholerae (Classical, Inaba) were radiolabeled with Iodogen or Iodo-beads as catalyst. Radiolabeling of whole cells was shown to be surface specific by sodium dodecyl sulfate-urea polyacrylamide gel electrophoresis of whole cells and cell fractions. Surface-labeled whole cells regularly showed 16 distinguishable protein species, of which nine were found in radiolabeled outer membrane preparations obtained by a lithium chloride-lithium acetate procedure. Eight of these proteins were found in outer membranes prepared by sucrose density gradient centrifugation and Triton X-100 extraction of radiolabeled whole cells. The mobility of several proteins was shown to be affected by temperature, and the major protein species exposed on the cell surface was shown to consist of at least two different peptides. Images PMID:3980099
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In vitro cytotoxicity of calcium silicate-containing endodontic sealers.
Zhou, Hui-min; Du, Tian-feng; Shen, Ya; Wang, Zhe-jun; Zheng, Yu-feng; Haapasalo, Markus
2015-01-01
The cytotoxicity of 2 novel calcium silicate-containing endodontic sealers to human gingival fibroblasts was studied. EndoSequence BC (Brasseler, Savannah, GA), MTA Fillapex (Angelus Indústria de Produtos Odontológicos S/A, Londrina, PR, Brazil) and a control sealer (AH Plus; Dentsply DeTrey GmbH, Konstanz, Germany) were evaluated. Human gingival fibroblasts were incubated for 3 days both with the extracts from fresh and set materials in culture medium and cultured on the surface of the set materials in Dulbecco-modified Eagle medium. Fibroblasts cultured in Dulbecco-modified Eagle medium were used as a control group. Cytotoxicity was evaluated by flow cytometry, and the adhesion of the fibroblasts to the surface of the set materials was assessed using scanning electron microscopy. The data of cell cytotoxicity were analyzed statistically using a 1-way analysis of variance test at a significance level of P < .05. Cells incubated with extracts from BC Sealer showed higher viabilities at all extract concentrations than cells incubated with extracts from freshly mixed AH Plus and fresh and set MTA Fillapex, esspecially for the high extract concentrations (1:2 and 1:8 dilutions). Extracts from set MTA Fillapex of 2 weeks and older were more cytotoxic than extracts from freshly mixed and 1-week-old cement. With extract concentrations of 1:32 and lower, MTA Fillapex was no longer cytotoxic. After setting, AH Plus was no longer cytotoxic, and the fibroblast cells grew on set AH Plus equally as well as on BC Sealer. BC Sealer and MTA Fillapex, the 2 calcium silicate-containing endodontic sealers, exhibited different cytotoxicity to human gingival fibroblasts. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
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The Voltage Boost Enabled by Luminescence Extraction in Solar Cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ganapati, Vidya; Steiner, Myles A.; Yablonovitch, Eli
Over the past few years, the application of the physical principle, i.e., 'luminescence extraction,' has produced record voltages and efficiencies in photovoltaic cells. Luminescence extraction is the use of optical design, such as a back mirror or textured surfaces, to help internal photons escape out of the front surface of a solar cell. The principle of luminescence extraction is exemplified by the mantra 'a good solar cell should also be a good LED.' Basic thermodynamics says that the voltage boost should be related to concentration ratio C of a resource by ΔV = (kT/q) ln{C}. In light trapping (i.e., when the solar cell is textured and has a perfect back mirror), the concentration ratio of photons C = {4n 2}; therefore, one would expect a voltage boost of ΔV = (kT/q) ln{4n 2} over a solar cell with no texture and zero back reflectivity, where n is the refractive index. Nevertheless, there has been ambiguity over the voltage benefit to be expected from perfect luminescence extraction. Do we gain an open-circuit voltage boost of ΔV = (kT/q) ln{n 2}, ΔV = (kT/q) ln{2 n 2}, or ΔV = (kT/q) ln{4 n 2}? What is responsible for this voltage ambiguity ΔV = (kT/q) ln{4}more » $${\\asymp}$$ 36 mV? Finally, we show that different results come about, depending on whether the photovoltaic cell is optically thin or thick to its internal luminescence. In realistic intermediate cases of optical thickness, the voltage boost falls in between: ln{n 2} < (qΔV/kT) < ln{4n 2}.« less
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The Voltage Boost Enabled by Luminescence Extraction in Solar Cells
Ganapati, Vidya; Steiner, Myles A.; Yablonovitch, Eli
2016-07-01
Over the past few years, the application of the physical principle, i.e., 'luminescence extraction,' has produced record voltages and efficiencies in photovoltaic cells. Luminescence extraction is the use of optical design, such as a back mirror or textured surfaces, to help internal photons escape out of the front surface of a solar cell. The principle of luminescence extraction is exemplified by the mantra 'a good solar cell should also be a good LED.' Basic thermodynamics says that the voltage boost should be related to concentration ratio C of a resource by ΔV = (kT/q) ln{C}. In light trapping (i.e., when the solar cell is textured and has a perfect back mirror), the concentration ratio of photons C = {4n 2}; therefore, one would expect a voltage boost of ΔV = (kT/q) ln{4n 2} over a solar cell with no texture and zero back reflectivity, where n is the refractive index. Nevertheless, there has been ambiguity over the voltage benefit to be expected from perfect luminescence extraction. Do we gain an open-circuit voltage boost of ΔV = (kT/q) ln{n 2}, ΔV = (kT/q) ln{2 n 2}, or ΔV = (kT/q) ln{4 n 2}? What is responsible for this voltage ambiguity ΔV = (kT/q) ln{4}more » $${\\asymp}$$ 36 mV? Finally, we show that different results come about, depending on whether the photovoltaic cell is optically thin or thick to its internal luminescence. In realistic intermediate cases of optical thickness, the voltage boost falls in between: ln{n 2} < (qΔV/kT) < ln{4n 2}.« less
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NASA Astrophysics Data System (ADS)
Shi, Wenzhong; Deng, Susu; Xu, Wenbing
2018-02-01
For automatic landslide detection, landslide morphological features should be quantitatively expressed and extracted. High-resolution Digital Elevation Models (DEMs) derived from airborne Light Detection and Ranging (LiDAR) data allow fine-scale morphological features to be extracted, but noise in DEMs influences morphological feature extraction, and the multi-scale nature of landslide features should be considered. This paper proposes a method to extract landslide morphological features characterized by homogeneous spatial patterns. Both profile and tangential curvature are utilized to quantify land surface morphology, and a local Gi* statistic is calculated for each cell to identify significant patterns of clustering of similar morphometric values. The method was tested on both synthetic surfaces simulating natural terrain and airborne LiDAR data acquired over an area dominated by shallow debris slides and flows. The test results of the synthetic data indicate that the concave and convex morphologies of the simulated terrain features at different scales and distinctness could be recognized using the proposed method, even when random noise was added to the synthetic data. In the test area, cells with large local Gi* values were extracted at a specified significance level from the profile and the tangential curvature image generated from the LiDAR-derived 1-m DEM. The morphologies of landslide main scarps, source areas and trails were clearly indicated, and the morphological features were represented by clusters of extracted cells. A comparison with the morphological feature extraction method based on curvature thresholds proved the proposed method's robustness to DEM noise. When verified against a landslide inventory, the morphological features of almost all recent (< 5 years) landslides and approximately 35% of historical (> 10 years) landslides were extracted. This finding indicates that the proposed method can facilitate landslide detection, although the cell clusters extracted from curvature images should be filtered using a filtering strategy based on supplementary information provided by expert knowledge or other data sources.
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Studies by immune electron microscopy of hepatitis B surface antigen in PLC/PRF/5 cells.
Shibayama, T; Watanabe, T; Kojima, H; Yoshikawa, A; Watanabe, S; Kamimura, T; Suzuki, S; Ichida, F
1984-01-01
Electron microscopic studies of the morphology of hepatitis B surface antigen (HBsAg) produced by PLC/PRF/5 cells in vitro were carried out. Aggregates of 20-nm spherical particles in 3-day culture supernatants were observed by immune electron microscopy (IEM). Aggregates of tubular structures were found with IEM in the extracts of the cells. Tubular structures 18 to 22 nm in diameter were seen by electron microscopy (EM) in the cisternae of the endoplasmic reticulum in 2-3% of the cells. The tubular structures in the cytoplasm and extracts of PLC/PRF/5 cells resembled those observed in the hepatocytes of human carriers of hepatitis B virus (HBV). Intracellular localization of HBsAg in PLC/PRF/5 cells by direct peroxidase-conjugated antibody staining was observed on the tubular structures and the cisternal wall, which contained these structures. Rotation technique analysis indicated that the tubular structures were composed of 11 or 12 subunits.
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Parallel RNA extraction using magnetic beads and a droplet array.
Shi, Xu; Chen, Chun-Hong; Gao, Weimin; Chao, Shih-Hui; Meldrum, Deirdre R
2015-02-21
Nucleic acid extraction is a necessary step for most genomic/transcriptomic analyses, but it often requires complicated mechanisms to be integrated into a lab-on-a-chip device. Here, we present a simple, effective configuration for rapidly obtaining purified RNA from low concentration cell medium. This Total RNA Extraction Droplet Array (TREDA) utilizes an array of surface-adhering droplets to facilitate the transportation of magnetic purification beads seamlessly through individual buffer solutions without solid structures. The fabrication of TREDA chips is rapid and does not require a microfabrication facility or expertise. The process takes less than 5 minutes. When purifying mRNA from bulk marine diatom samples, its repeatability and extraction efficiency are comparable to conventional tube-based operations. We demonstrate that TREDA can extract the total mRNA of about 10 marine diatom cells, indicating that the sensitivity of TREDA approaches single-digit cell numbers.
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Parallel RNA extraction using magnetic beads and a droplet array
Shi, Xu; Chen, Chun-Hong; Gao, Weimin; Meldrum, Deirdre R.
2015-01-01
Nucleic acid extraction is a necessary step for most genomic/transcriptomic analyses, but it often requires complicated mechanisms to be integrated into a lab-on-a-chip device. Here, we present a simple, effective configuration for rapidly obtaining purified RNA from low concentration cell medium. This Total RNA Extraction Droplet Array (TREDA) utilizes an array of surface-adhering droplets to facilitate the transportation of magnetic purification beads seamlessly through individual buffer solutions without solid structures. The fabrication of TREDA chips is rapid and does not require a microfabrication facility or expertise. The process takes less than 5 minutes. When purifying mRNA from bulk marine diatom samples, its repeatability and extraction efficiency are comparable to conventional tube-based operations. We demonstrate that TREDA can extract the total mRNA of about 10 marine diatom cells, indicating that the sensitivity of TREDA approaches single-digit cell numbers. PMID:25519439
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Hui, Yew Woh; Dykes, Gary A
2012-08-01
The use of simple crude water extracts of common herbs to reduce bacterial attachment may be a cost-effective way to control bacterial foodborne pathogens, particularly in developing countries. The ability of water extracts of three common Malaysian herbs (Andrographis paniculata, Eurycoma longifolia, and Garcinia atroviridis) to modulate hydrophobicity and attachment to surfaces of five food-related bacterial strains (Bacillus cereus ATCC 14576, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 10145, Salmonella Enteritidis ATCC 13076, Staphylococcus aureus ATCC 25923) were determined. The bacterial attachment to hydrocarbon assay was used to determine bacterial hydrophobicity. Staining and direct microscopic counts were used to determine attachment of bacteria to glass and stainless steel. Plating on selective media was used to determine attachment of bacteria to shrimp. All extracts were capable of either significantly ( P < 0.05) increasing or decreasing bacterial surface hydrophobicity, depending on the herb extract and bacteria combination. Bacterial attachment to all surfaces was either significantly (P < 0.05) increased or decreased, depending on the herb extract and bacteria combination. Overall, hydrophobicity did not show a significant correlation (P > 0.05) to bacterial attachment. For specific combinations of bacteria, surface material, and plant extract, significant correlations (R > 0.80) between hydrophobicity and attachment were observed. The highest of these was observed for S. aureus attachment to stainless steel and glass after treatment with the E. longifolia extract (R = 0.99, P < 0.01). The crude water herb extracts in this study were shown to have the potential to modulate specific bacterial and surface interactions and may, with further work, be useful for the simple and practical control of foodborne pathogens.
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Mapping cell surface adhesion by rotation tracking and adhesion footprinting
NASA Astrophysics Data System (ADS)
Li, Isaac T. S.; Ha, Taekjip; Chemla, Yann R.
2017-03-01
Rolling adhesion, in which cells passively roll along surfaces under shear flow, is a critical process involved in inflammatory responses and cancer metastasis. Surface adhesion properties regulated by adhesion receptors and membrane tethers are critical in understanding cell rolling behavior. Locally, adhesion molecules are distributed at the tips of membrane tethers. However, how functional adhesion properties are globally distributed on the individual cell’s surface is unknown. Here, we developed a label-free technique to determine the spatial distribution of adhesive properties on rolling cell surfaces. Using dark-field imaging and particle tracking, we extract the rotational motion of individual rolling cells. The rotational information allows us to construct an adhesion map along the contact circumference of a single cell. To complement this approach, we also developed a fluorescent adhesion footprint assay to record the molecular adhesion events from cell rolling. Applying the combination of the two methods on human promyelocytic leukemia cells, our results surprisingly reveal that adhesion is non-uniformly distributed in patches on the cell surfaces. Our label-free adhesion mapping methods are applicable to the variety of cell types that undergo rolling adhesion and provide a quantitative picture of cell surface adhesion at the functional and molecular level.
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Activation of Cell Surface Bound 20S Proteasome Inhibits Vascular Cell Growth and Arteriogenesis
Ito, Wulf D.; Lund, Natalie; Zhang, Ziyang; Buck, Friedrich; Lellek, Heinrich; Horst, Andrea; Machens, Hans-Günther; Schunkert, Heribert; Schaper, Wolfgang; Meinertz, Thomas
2015-01-01
Arteriogenesis is an inflammatory process associated with rapid cellular changes involving vascular resident endothelial progenitor cells (VR-EPCs). Extracellular cell surface bound 20S proteasome has been implicated to play an important role in inflammatory processes. In our search for antigens initially regulated during collateral growth mAb CTA 157-2 was generated against membrane fractions of growing collateral vessels. CTA 157-2 stained endothelium of growing collateral vessels and the cell surface of VR-EPCs. CTA 157-2 bound a protein complex (760 kDa) that was identified as 26 kDa α7 and 21 kDa β3 subunit of 20S proteasome in mass spectrometry. Furthermore we demonstrated specific staining of 20S proteasome after immunoprecipitation of VR-EPC membrane extract with CTA 157-2 sepharose beads. Functionally, CTA 157-2 enhanced concentration dependently AMC (7-amino-4-methylcoumarin) cleavage from LLVY (N-Succinyl-Leu-Leu-Val-Tyr) by recombinant 20S proteasome as well as proteasomal activity in VR-EPC extracts. Proliferation of VR-EPCs (BrdU incorporation) was reduced by CTA 157-2. Infusion of the antibody into the collateral circulation reduced number of collateral arteries, collateral proliferation, and collateral conductance in vivo. In conclusion our results indicate that extracellular cell surface bound 20S proteasome influences VR-EPC function in vitro and collateral growth in vivo. PMID:26146628
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Kaushik, Jyoti; Tandon, Simran; Gupta, Varun; Nayyar, Jasamrit; Singla, Surinder Kumar; Tandon, Chanderdeep
2017-01-01
Tribulus terrestris has significant antilithiatic efficacy established via both in vitro as well as in vivo studies and is used in numerous anti-urolithiatic herbal formulations viz. Cystone, Uriflow, Uritone and Neeri. However, to fully utilize its antilithiatic potential, the influence of different extraction parameters on antilithiatic ability of T. terrestris aqueous extract needs elucidation. Thus, the current study was undertaken using statistically optimized extraction conditions for aqueous extract preparation. Response surface methodology was employed to observe the influence of three variables i.e. temperature (°C), time (h) and solid: liquid ratio (S: L) on the extraction yield (%) and protein content (mg/g) of T. terrestris aqueous extract. RSM results revealed that the high S:L ratio, low temperature and reduced incubation time were optimal conditions for aqueous extraction. Under such extraction conditions the protein content reached the value of 26.6±1.22 mg/g and the obtained extraction yield was 27.32±1.62%. The assessment of antilithiatic activity of 4 selected extracts (AE1-4), revealed enhanced nucleation and aggregation inhibition of calcium oxalate crystals with AE1 and AE2, which in addition significantly altered the size and morphology of calcium oxalate monohydrate (COM) crystals compared to AE3 and AE4. In vitro cell culture based studies on renal epithelial cells (MDCK, NRK-52E and PK 15) proved that the AE1 showed higher cytoprotective potency by increasing cell viability as compared to the oxalate treated group. The free radical scavenging activity of aqueous extract lowered the reactive oxygen specie's induced damage and potentially reduced the signals of programmed cell death due to oxalate injury. In addition, modulation of the COM crystal morphology was enhanced by AE1 as compared to AE2. The FTIR and GC-MS analysis of AE1, showed the presence of biomolecules which could aid in the attenuation of lithiatic process. In the light of these results the utility of the RSM approach to fully optimize the antilithiatic potential of T. terrestris cannot be undermined.
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Kaushik, Jyoti; Tandon, Simran; Gupta, Varun; Nayyar, Jasamrit; Singla, Surinder Kumar; Tandon, Chanderdeep
2017-01-01
Tribulus terrestris has significant antilithiatic efficacy established via both in vitro as well as in vivo studies and is used in numerous anti-urolithiatic herbal formulations viz. Cystone, Uriflow, Uritone and Neeri. However, to fully utilize its antilithiatic potential, the influence of different extraction parameters on antilithiatic ability of T. terrestris aqueous extract needs elucidation. Thus, the current study was undertaken using statistically optimized extraction conditions for aqueous extract preparation. Response surface methodology was employed to observe the influence of three variables i.e. temperature (°C), time (h) and solid: liquid ratio (S: L) on the extraction yield (%) and protein content (mg/g) of T. terrestris aqueous extract. RSM results revealed that the high S:L ratio, low temperature and reduced incubation time were optimal conditions for aqueous extraction. Under such extraction conditions the protein content reached the value of 26.6±1.22 mg/g and the obtained extraction yield was 27.32±1.62%. The assessment of antilithiatic activity of 4 selected extracts (AE1-4), revealed enhanced nucleation and aggregation inhibition of calcium oxalate crystals with AE1 and AE2, which in addition significantly altered the size and morphology of calcium oxalate monohydrate (COM) crystals compared to AE3 and AE4. In vitro cell culture based studies on renal epithelial cells (MDCK, NRK-52E and PK 15) proved that the AE1 showed higher cytoprotective potency by increasing cell viability as compared to the oxalate treated group. The free radical scavenging activity of aqueous extract lowered the reactive oxygen specie’s induced damage and potentially reduced the signals of programmed cell death due to oxalate injury. In addition, modulation of the COM crystal morphology was enhanced by AE1 as compared to AE2. The FTIR and GC-MS analysis of AE1, showed the presence of biomolecules which could aid in the attenuation of lithiatic process. In the light of these results the utility of the RSM approach to fully optimize the antilithiatic potential of T. terrestris cannot be undermined. PMID:28846699
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilder, R.L.; Yuen, C.C.; Mage, R.G.
1979-02-01
Rabbit and mouse splenic lymphocytes were radioiodinated by the lactoperoxidase technique, extracted with non-ionic detergent, immunoprecipitated with high titered rabbit anti-kappa antisera, and compared by SDS-PAGE. Mouse sIg peaks were reproducibly larger in size than rabbit sIg peaks (often greater than 10 times). Neither differences in incorporation of label into the rabbit cell surface, nor differences in average sIg density explain this result. Total TCA-precipitable radioactivity was similar in each species. Estimation of the relative amounts of sIg in the mouse and rabbit showed similar average sIg densities. Differences in detergent solubility, proteolytic lability, or antisera used also do notmore » adequately account for this difference. Thus, these data indicate that radioactivity incorporated after lactoperoxidase catalyzed cell surface radioiodination may not reflect cell surface Ig density. Conclusions about cell surface density based upon relative incorporation of radioactivity should be confirmed by other approaches.« less
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21 CFR 178.3620 - Mineral oil.
Code of Federal Regulations, 2010 CFR
2010-04-01
... extract in a 10-millimeter cell in the range from 260-350 mµ, inclusive, compared to the solvent control... hole bored in the center to closely fit the stem of the chromatographic tube. Suction flask. 250... surface of contained liquid to be evaporated. Spectrophotometric cells. Fused quartz cells, optical path...
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21 CFR 178.3620 - Mineral oil.
Code of Federal Regulations, 2013 CFR
2013-04-01
... extract in a 10-millimeter cell in the range from 260-350 mµ, inclusive, compared to the solvent control... hole bored in the center to closely fit the stem of the chromatographic tube. Suction flask. 250... surface of contained liquid to be evaporated. Spectrophotometric cells. Fused quartz cells, optical path...
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21 CFR 178.3620 - Mineral oil.
Code of Federal Regulations, 2011 CFR
2011-04-01
... extract in a 10-millimeter cell in the range from 260-350 mµ, inclusive, compared to the solvent control... hole bored in the center to closely fit the stem of the chromatographic tube. Suction flask. 250... surface of contained liquid to be evaporated. Spectrophotometric cells. Fused quartz cells, optical path...
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21 CFR 178.3620 - Mineral oil.
Code of Federal Regulations, 2012 CFR
2012-04-01
... extract in a 10-millimeter cell in the range from 260-350 mµ, inclusive, compared to the solvent control... hole bored in the center to closely fit the stem of the chromatographic tube. Suction flask. 250... surface of contained liquid to be evaporated. Spectrophotometric cells. Fused quartz cells, optical path...
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Deters, Alexandra; Zippel, Janina; Hellenbrand, Nils; Pappai, Dirk; Possemeyer, Cathleen; Hensel, Andreas
2010-01-08
Aqueous extracts from the roots of Althea officinalis L. (Malvaceae) are widely used for treatment of irritated mucosa. The clinical proven effects are related to the presence of bioadhesive and mucilaginous polysaccharides from the rhamnogalacturonan type, leading to the physical formation of mucin-like on top of the irritated tissues. No data are available if the extracts or the polysaccharides from these extract exert an active influence on mucosal or connective tissue cells, in order to initiated changes in cell physiology, useful for better tissue regeneration. In vitro investigations of aqueous A. officinalis extract AE and raw polysaccharides (RPS) on epithelial KB cells and primary dermal human fibroblasts (pNHF) using WST1 vitality test and BrdU proliferation ELISA. Gene expression analysis by microarray from KB cells. Internalisation studies of polysaccharides were performed by laser scanning microscopy. AE (1, 10 microg/mL) had stimulating effect on cell viability and proliferation of epithelial KB cells. RPS (1, 10 microg/mL) stimulated cell vitality of epithelial cells significantly without triggering the cells into higher proliferation status. Neither AE nor RPS had any effect on fibroblasts. FITC-labeled RPS was shown to be internalised into epithelial cells, but not into fibroblasts. FITC-RPS was shown to form bioadhesive layers on the cell surface of dermal fibroblasts. Microarray analysis indicated an up-regulation of genes related to cell adhesion proteins, growth regulators, extracellular matrix, cytokine release and apoptosis. Aqueous extracts and polysaccharides from the roots of A. officinalis are effective stimulators of cell physiology of epithelial cells which can prove the traditional use of Marshmallow preparations for treatment of irritated mucous membranes within tissue regeneration. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.
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Deformation and relaxation of an incompressible viscoelastic body with surface viscoelasticity
NASA Astrophysics Data System (ADS)
Liu, Liping; Yu, Miao; Lin, Hao; Foty, Ramsey
2017-01-01
Measuring mechanical properties of cells or cell aggregates has proven to be an involved process due to their geometrical and structural complexity. Past measurements are based on material models that completely neglect the elasticity of either the surface membrane or the interior bulk. In this work, we consider general material models to account for both surface and bulk viscoelasticity. The boundary value problems are formulated for deformations and relaxations of a closed viscoelastic surface coupled with viscoelastic media inside and outside of the surface. The linearized surface elasticity models are derived for the constant surface tension model and the Helfrich-Canham bending model for coupling with the bulk viscoelasticity. For quasi-spherical surfaces, explicit solutions are obtained for the deformation, stress-strain and relaxation behaviors under a variety of loading conditions. These solutions can be applied to extract the intrinsic surface and bulk viscoelastic properties of biological cells or cell aggregates in the indentation, electro-deformation and relaxation experiments.
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Striped Electrodes for Solid-Electrolyte Cells
NASA Technical Reports Server (NTRS)
Richter, R.
1983-01-01
Striped thick-film platinum electrodes help insure lower overall cell resistance by permitting free flow of gases in gaps between stripes. Thickfilm stripes are also easier to fabricate than porous thin-film electrodes that cover entire surface. Possible applications for improved cells include oxygen production from carbon dioxide, extraction of oxygen from air, small fluidic pumping, sewage treatment, and fuel cells.
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Split rheometer Couette attachment to enable sample extraction
NASA Astrophysics Data System (ADS)
Guthrie, Sarah E.; Idziak, Stefan H. J.
2005-02-01
We report on the development of a Couette attachment insert for a rheometer, which is designed to split in half, enabling intact sample extraction of cocoa butter crystallized from the melt under known dynamic stress conditions. This cell is capable of producing a sample 1mm thick. At shear rates of 90-720s-1 and final temperatures of 18-20°C it was shown that the sample will completely separate from the cell surface intact.
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Shrivastava, Ravi
2011-04-01
The aim of this study was to evaluate the chronic wound healing properties of tannin rich plant extracts. The cell growth stimulating potential of 128 procyanidin rich plant extracts was evaluated in in vitro cell culture models. For clinical trial, a 3% solution of two plant extracts having synergistic effect on cell growth was prepared in glycerol and honey. Placebo test product contained only glycerol and honey. 93 adult patients with one or more lower extremity deep wounds were divided at randomly in two groups. 41 patients in the placebo (AS-22) and 52 in the active treatment (AS-21) groups having respectively 49 and 69 wounds of a mean surface area of 56.70 and 52.03 cm(2), and volume of 57.22 and 52.15 cm(3), were treated by applying the test products topically for a period of 6-weeks. A statistically significant difference was observed between the placebo and the AS-21 treated groups with respect to reduction in the wound surface area (33.37 vs 97.87%) and wound volume (29.45 vs 94.17%) after 6-weeks of treatment. Mean wound humidity and pain scores were also reduced. Tannin rich plant extracts are highly interesting for the treatment of chronic wounds. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
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Gupta, R S; Kachhawa, J B S; Chaudhary, R
2006-03-01
Methanolic extract of Albizia lebbeck bark when administered orally at the dose level of 100 mg/rat/day to male rats of proven fertility for 60 days did not cause any significant loss in their body weights but the weights of reproductive organs, i.e. testis, epididymides, seminal vesicle and ventral prostate were decreased in a significant manner when compared to controls. Sperm motility as well as sperm density were reduced significantly which resulted in reduction of male fertility by 100%. Marked decline in the germ cell population was noticed. Population of preleptotene, pachytene, secondary spermatocytes and step-19 spermatid were declined by 60.86%, 65.81%, 71.56% and 66.55%, respectively. Cross-sectional surface area of sertoli cells as well as the cells counts were found to be depleted significantly. Leydig cells nuclear area and number of mature Leydig cells were decreased by 60.03% and 51.56%, respectively. Serum testosterone levels showed significant reduction after A. lebbeck extract feeding. Oral administration of the extract did not affect red blood cell (RBC) and white blood cell (WBC) count, haemoglobin, haematocrit and glucose in the blood and cholesterol, protein, triglyceride and phospholipid in the serum. In conclusion, A. lebbeck bark extract administration arrests spermatogenesis in male rats without noticeable side effects.
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Hashimoto, Ayako; Ohkura, Katsuma; Takahashi, Masakazu; Kizu, Kumiko; Narita, Hiroshi; Enomoto, Shuichi; Miyamae, Yusaku; Masuda, Seiji; Nagao, Masaya; Irie, Kazuhiro; Ohigashi, Hajime; Andrews, Glen K; Kambe, Taiho
2015-12-01
Dietary zinc deficiency puts human health at risk, so we explored strategies for enhancing zinc absorption. In the small intestine, the zinc transporter ZIP4 functions as an essential component of zinc absorption. Overexpression of ZIP4 protein increases zinc uptake and thereby cellular zinc levels, suggesting that food components with the ability to increase ZIP4 could potentially enhance zinc absorption via the intestine. In the present study, we used mouse Hepa cells, which regulate mouse Zip4 (mZip4) in a manner indistinguishable from that in intestinal enterocytes, to screen for suitable food components that can increase the abundance of ZIP4. Using this ZIP4-targeting strategy, two such soybean extracts were identified that were specifically able to decrease mZip4 endocytosis in response to zinc. These soybean extracts also effectively increased the abundance of apically localized mZip4 in transfected polarized Caco2 and Madin-Darby canine kidney cells and, moreover, two apically localized mZip4 acrodermatitis enteropathica mutants. Soybean components were purified from one extract and soyasaponin Bb was identified as an active component that increased both mZip4 protein abundance and zinc levels in Hepa cells. Finally, we confirmed that soyasaponin Bb is capable of enhancing cell surface endogenous human ZIP4 in human cells. Our results suggest that ZIP4 targeting may represent a new strategy to improve zinc absorption in humans. © 2015 Authors; published by Portland Press Limited.
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Adhesions of extracellular surface-layer associated proteins in Lactobacillus M5-L and Q8-L.
Zhang, Yingchun; Xiang, Xinling; Lu, Qianhui; Zhang, Lanwei; Ma, Fang; Wang, Linlin
2016-02-01
Surface-layer associated proteins (SLAP) that envelop Lactobacillus paracasei ssp. paracasei M5-L and Lactobacillus casei Q8-L cell surfaces are involved in the adherence of these strain to the human intestinal cell line HT-29. To further elucidate some of the properties of these proteins, we assessed the yields and expressions of SLAP under different incubation conditions. An efficient and selective extraction of SLAP was obtained when cells of Lactobacillus were treated with 5 M LiCl at 37°C in aerobic conditions. The SLAP of Lactobacillus M5-L and Q8-L in cell extracts were visualized by SDS-PAGE and identified by Western blotting with sulfo-N-hydroxysuccinimide-biotin-labeled HT-29 cells as adhesion proteins. Atomic force microscopy contact imaging revealed that Lactobacillus strains M5-L and Q8-L normally display a smooth, homogeneous surface, whereas the surfaces of M5-L and Q8-L treated with 5 M LiCl were rough and more heterogeneous. Analysis of adhesion forces revealed that the initial adhesion forces of 1.41 and 1.28 nN obtained for normal Lactobacillus M5-L and Q8-L strains, respectively, decreased to 0.70 and 0.48 nN, respectively, following 5 M LiCl treatment. Finally, the dominant 45-kDa protein bands of Lactobacillus Q8-L and Lactobacillus M5-L were identified as elongation factor Tu and surface antigen, respectively, by liquid chromatography-tandem mass spectrometry. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
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Wang, Xiaoqin; Jiang, Ying; Hu, Daode
2017-01-02
The objective of the study was to optimize the ultrasonic-assisted extraction of curdione, furanodienone, curcumol, and germacrone from Curcuma phaeocaulis Valeton (Val.) and investigate the antiproliferative activity of the extract. Under the suitable high-performance liquid chromatography condition, the calibration curves for these four tested compounds showed high levels of linearity and the recoveries of these four compounds were between 97.9 and 104.3%. Response surface methodology (RSM) combining central composite design and desirability function (DF) was used to define optimal extraction parameters. The results of RSM and DF revealed that the optimum conditions were obtained as 8 mL g -1 for liquid-solid ratio, 70% ethanol concentration, and 20 min of ultrasonic time. It was found that the surface structures of the sonicated herbal materials were fluffy and irregular. The C. phaeocaulis Val. extract significantly inhibited the proliferation of RKO and HT-29 cells in vitro. The results reveal that the RSM can be effectively used for optimizing the ultrasonic-assisted extraction of bioactive components from C. phaeocaulis Val. for antiproliferative activity.
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Prueksakorn, Attaporn; Puasiri, Subin; Ruangsri, Supanigar; Makeudom, Anupong; Sastraruji, Thanapat; Krisanaprakornkit, Suttichai; Chailertvanitkul, Pattama
2016-12-01
Tooth avulsion causes an injury to the periodontal ligament (PDL). The success of tooth replantation depends on the quantity and quality of PDL cells. The aim of this study was to examine the preservative and proliferative effects of Thai propolis extract, previously shown to exert anti-inflammatory and antioxidant activities, on human PDL cells. Ninety-six premolars were left to air dry for 30 min and stored in Hank's balanced salt solution (HBSS), milk, or various concentrations of propolis extract from 0.25 to 10 mg ml -1 for 3 h. PDL cells were isolated by collagenase and trypsin digestion, and their viability was determined by a trypan blue dye exclusion assay. PDL tissues were also scraped off the root surface and cultured to determine cell growth and morphology. The alamarBlue ® and BrdU assays were performed to determine the cytotoxic and proliferative effects of the extract on cultured PDL cells, respectively. A non-toxic dose of 2.5 mg ml -1 of propolis extract yielded the greatest percentage of cell viability (78.84 ± 3.34%), which was significantly higher than those of the other concentrations (P < 0.001). Nevertheless, this percentage was not significantly different from that of HBSS (80.14 ± 2.44%; P = 1.00), but was significantly higher than that of milk (71.27 ± 2.79%; P < 0.001). The cells grown from PDL explants looked like fibroblasts. However, 2.5 mg ml -1 of the extract did not induce PDL cell proliferation. Thai propolis extract at 2.5 mg ml -1 appears to be the most effective dose for preserving the viability of PDL cells, and this was comparable to HBSS. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Myocardial serotonin exchange: negligible uptake by capillary endothelium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moffett, T.C.; Chan, I.S.; Bassingthwaighte, J.B.
1988-03-01
The extraction of serotonin from the blood during transorgan passage through the heart was studied using Langendorff-perfused rabbit hearts. Outflow dilution curves of /sup 131/I- or /sup 125/I-labeled albumin, (/sup 14/C)sucrose, and (3H)serotonin injected simultaneously into the inflow were fitted with an axially distributed blood-tissue exchange model to examine the extraction process. The model fits of the albumin and sucrose outflow dilution curves were used to define flow heterogeneity, intravascular dispersion, capillary permeability, and the volume of the interstitial space, which reduced the degrees of freedom in fitting the model to the serotonin curves. Serotonin extractions, measured against albumin, duringmore » single transcapillary passage, ranged from 24 to 64%. The ratio of the capillary permeability-surface area products for serotonin and sucrose, based on the maximum instantaneous extraction, was 1.37 +/- 0.2 (n = 18), very close to the predicted value of 1.39, the ratio of free diffusion coefficients calculated from the molecular weights. This result shows that the observed uptake of serotonin can be accounted for solely on the basis of diffusion between endothelial cells into the interstitial space. Thus it appears that the permeability of the luminal surface of the endothelial cell is negligible in comparison to diffusion through the clefts between endothelial cells. In 18 sets of dilution curves, with and without receptor and transport blockers or competitors (ketanserin, desipramine, imipramine, serotonin), the extractions and estimates of the capillary permeability-surface area product were not reduced, nor were the volumes of distribution. The apparent absence of transporters and receptors in rabbit myocardial capillary endothelium contrasts with their known abundance in the pulmonary vasculature.« less
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NASA Astrophysics Data System (ADS)
Hossain, Md. Khalid; Pervez, M. Firoz; Mia, M. N. H.; Mortuza, A. A.; Rahaman, M. S.; Karim, M. R.; Islam, Jahid M. M.; Ahmed, Farid; Khan, Mubarak A.
In this study, natural dye sensitizer based solar cells were successfully fabricated and photovoltaic performance was measured. Sensitizer (turmeric) sources, dye extraction process, and photoanode sensitization time of the fabricated cells were analyzed and optimized. Dry turmeric, verdant turmeric, and powder turmeric were used as dye sources. Five distinct types of solvents were used for extraction of natural dye from turmeric. Dyes were characterized by UV-Vis spectrophotometric analysis. The extracted turmeric dye was used as a sensitizer in the dye sensitized solar cell's (DSSC) photoanode assembly. Nano-crystalline TiO2 was used as a film coating semiconductor material of the photoanode. TiO2 films on ITO glass substrate were prepared by simple doctor blade technique. The influence of the different parameters VOC, JSC, power density, FF, and η% on the photovoltaic characteristics of DSSCs was analyzed. The best energy conversion performance was obtained for 2 h adsorption time of dye on TiO2 nano-porous surface with ethanol extracted dye from dry turmeric.
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Wang, Guifang; Li, Jinhua; Zhang, Wenjie; Xu, Lianyi; Pan, Hongya; Wen, Jin; Wu, Qianju; She, Wenjun; Jiao, Ting; Liu, Xuanyong; Jiang, Xinquan
2014-01-01
As one of the important ions associated with bone osseointegration, magnesium was incorporated into a micro/nanostructured titanium surface using a magnesium plasma immersion ion-implantation method. Hierarchical hybrid micro/nanostructured titanium surfaces followed by magnesium ion implantation for 30 minutes (Mg30) and hierarchical hybrid micro/nanostructured titanium surfaces followed by magnesium ion implantation for 60 minutes (Mg60) were used as test groups. The surface morphology, chemical properties, and amount of magnesium ions released were evaluated by field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, field-emission transmission electron microscopy, and inductively coupled plasma-optical emission spectrometry. Rat bone marrow mesenchymal stem cells (rBMMSCs) were used to evaluate cell responses, including proliferation, spreading, and osteogenic differentiation on the surface of the material or in their medium extraction. Greater increases in the spreading and proliferation ability of rBMMSCs were observed on the surfaces of magnesium-implanted micro/nanostructures compared with the control plates. Furthermore, the osteocalcin (OCN), osteopontin (OPN), and alkaline phosphatase (ALP) genes were upregulated on both surfaces and in their medium extractions. The enhanced cell responses were correlated with increasing concentrations of magnesium ions, indicating that the osteoblastic differentiation of rBMMSCs was stimulated through the magnesium ion function. The magnesium ion-implanted micro/nanostructured titanium surfaces could enhance the proliferation, spreading, and osteogenic differentiation activity of rBMMSCs, suggesting they have potential application in improving bone-titanium integration. PMID:24940056
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Investigation of the Cell Surface Proteome of Human Periodontal Ligament Stem Cells
Xiong, Jimin; Menicanin, Danijela; Marino, Victor
2016-01-01
The present study examined the cell surface proteome of human periodontal ligament stem cells (PDLSC) compared to human fibroblasts. Cell surface proteins were prelabelled with CyDye before processing to extract the membrane lysates, which were separated using 2D electrophoresis. Selected differentially expressed protein “spots” were identified using Mass spectrometry. Four proteins were selected for validation: CD73, CD90, Annexin A2, and sphingosine kinase 1 previously associated with mesenchymal stem cells. Flow cytometric analysis found that CD73 and CD90 were highly expressed by human PDLSC and gingival fibroblasts but not by keratinocytes, indicating that these antigens could be used as potential markers for distinguishing between mesenchymal cells and epithelial cell populations. Annexin A2 was also found to be expressed at low copy number on the cell surface of human PDLSC and gingival fibroblasts, while human keratinocytes lacked any cell surface expression of Annexin A2. In contrast, sphingosine kinase 1 expression was detected in all the cell types examined using immunocytochemical analysis. These proteomic studies form the foundation to further define the cell surface protein expression profile of PDLSC in order to better characterise this cell population and help develop novel strategies for the purification of this stem cell population. PMID:27579043
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Investigation of the Cell Surface Proteome of Human Periodontal Ligament Stem Cells.
Xiong, Jimin; Menicanin, Danijela; Zilm, Peter S; Marino, Victor; Bartold, P Mark; Gronthos, Stan
2016-01-01
The present study examined the cell surface proteome of human periodontal ligament stem cells (PDLSC) compared to human fibroblasts. Cell surface proteins were prelabelled with CyDye before processing to extract the membrane lysates, which were separated using 2D electrophoresis. Selected differentially expressed protein "spots" were identified using Mass spectrometry. Four proteins were selected for validation: CD73, CD90, Annexin A2, and sphingosine kinase 1 previously associated with mesenchymal stem cells. Flow cytometric analysis found that CD73 and CD90 were highly expressed by human PDLSC and gingival fibroblasts but not by keratinocytes, indicating that these antigens could be used as potential markers for distinguishing between mesenchymal cells and epithelial cell populations. Annexin A2 was also found to be expressed at low copy number on the cell surface of human PDLSC and gingival fibroblasts, while human keratinocytes lacked any cell surface expression of Annexin A2. In contrast, sphingosine kinase 1 expression was detected in all the cell types examined using immunocytochemical analysis. These proteomic studies form the foundation to further define the cell surface protein expression profile of PDLSC in order to better characterise this cell population and help develop novel strategies for the purification of this stem cell population.
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Production of immunologically active surface antigens of hepatitis B virus by Escherichia coli.
MacKay, P; Pasek, M; Magazin, M; Kovacic, R T; Allet, B; Stahl, S; Gilbert, W; Schaller, H; Bruce, S A; Murray, K
1981-01-01
Several plasmids have been constructed which direct the synthesis of hepatitis B virus surface antigens in Escherichia coli either as the native polypeptide or fused to other plasmid encoded polypeptides. When injected into rabbits, extracts from bacteria carrying some of these plasmids induced the synthesis of antibodies to the antigens even though the extracts did not give satisfactory positive results in radioimmunoassay for them. Either the NH2-terminal segment or the COOH-terminal segment of the surface antigens alone was sufficient to elicit the immune response, but antibodies against the two segments showed different specificities. The results emphasize the value of an in vivo assay for the presence of antigens in crude cell extracts and illustrate the feasibility of this type of screening with laboratory animals. PMID:6170067
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MPN estimation of qPCR target sequence recoveries from whole cell calibrator samples.
Sivaganesan, Mano; Siefring, Shawn; Varma, Manju; Haugland, Richard A
2011-12-01
DNA extracts from enumerated target organism cells (calibrator samples) have been used for estimating Enterococcus cell equivalent densities in surface waters by a comparative cycle threshold (Ct) qPCR analysis method. To compare surface water Enterococcus density estimates from different studies by this approach, either a consistent source of calibrator cells must be used or the estimates must account for any differences in target sequence recoveries from different sources of calibrator cells. In this report we describe two methods for estimating target sequence recoveries from whole cell calibrator samples based on qPCR analyses of their serially diluted DNA extracts and most probable number (MPN) calculation. The first method employed a traditional MPN calculation approach. The second method employed a Bayesian hierarchical statistical modeling approach and a Monte Carlo Markov Chain (MCMC) simulation method to account for the uncertainty in these estimates associated with different individual samples of the cell preparations, different dilutions of the DNA extracts and different qPCR analytical runs. The two methods were applied to estimate mean target sequence recoveries per cell from two different lots of a commercially available source of enumerated Enterococcus cell preparations. The mean target sequence recovery estimates (and standard errors) per cell from Lot A and B cell preparations by the Bayesian method were 22.73 (3.4) and 11.76 (2.4), respectively, when the data were adjusted for potential false positive results. Means were similar for the traditional MPN approach which cannot comparably assess uncertainty in the estimates. Cell numbers and estimates of recoverable target sequences in calibrator samples prepared from the two cell sources were also used to estimate cell equivalent and target sequence quantities recovered from surface water samples in a comparative Ct method. Our results illustrate the utility of the Bayesian method in accounting for uncertainty, the high degree of precision attainable by the MPN approach and the need to account for the differences in target sequence recoveries from different calibrator sample cell sources when they are used in the comparative Ct method. Published by Elsevier B.V.
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NASA Astrophysics Data System (ADS)
Djati, Muhammad Sasmito; Habibu, Hindun; Jatiatmaja, Nabilah A.; Rifa'i, Muhaimin
2017-11-01
Tapak Liman (Elephantopus scaber L) is a traditional medicinal plant containing several active compounds that potentially affecting hematopoietic stem cells, such as epifrieelinol, lupeol, stigmasterol, triacontane-1-ol, dotriacontane-1-ol, lupeol acetate, deoxyelephan-topin, isodeoxyelephantopin, polyphenol luteolin-7, as well as various flavonoids and glucosides. The aim of this study was to elucidate the effect of leaf extract of Tapak Liman on hematopoietic stem cells in mice BALB/c, by observation of the relative number of cells expressing CD4/CD8, CD4/CD62L, and TER119/B220 in the spleen, and TER119/B220, TER119/VLA-4 and TER119/CD34 in bone marrow, after being administered leaf extract for 2 weeks. This experiment used 12 female mice, which were divided into three treatment groups, P1= 0.5 g.g bw-1.day-1, P2= 1.0 g.g bw-1.day-1 and P3=2.0 g.g bw-1.day-1 Tapak Liman leaf extract as well as a control. The relative numbers of cells expressing surface molecules were analyzed by flowcytometry and quantitative data were tested using one-way ANOVA. The results showed that the leaf extract of Tapak Liman has no significant effect on erythrocyte proliferation; on the other hand, it had a significant effect on both proliferation and differentiation of B lymphocytes (B220+) in bone marrow (p=0.044) and increased the expression of CD4+, CD8+ molecule in B cells (p=0.026) and erythroid cells in spleen and bone marrow, based on the estimation of cells that expressed TER119+VLA-4+, identified as important in the development pathway of erythrocytes. An increased cell percentage of TER11+VLA-4+ occurred for treatment P2, 12% higher than the control. The increased expression of TER119+VLA-4+ was assumed to be due to the iron content in Tapak Liman, which functioned to stimulate the progenitor hematopoietic cells to proliferate and differentiate into a precursor of erythroid cells (TER119+VLA-4+). There was an increasing number of cells expressing the surface molecules TER119+ and VLA-4+. This indicated that the Tapak Liman leaf extract with a dose of 1.0 g.g bw-1.day-1 could stimulate the proliferation of hematopoietic stem cells into the lymphoid and erythroid pathway, in spleen and bone marrow.
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Surface deformation during an action potential in pearled cells
NASA Astrophysics Data System (ADS)
Mussel, Matan; Fillafer, Christian; Ben-Porath, Gal; Schneider, Matthias F.
2017-11-01
Electric pulses in biological cells (action potentials) have been reported to be accompanied by a propagating cell-surface deformation with a nanoscale amplitude. Typically, this cell surface is covered by external layers of polymer material (extracellular matrix, cell wall material, etc.). It was recently demonstrated in excitable plant cells (Chara braunii) that the rigid external layer (cell wall) hinders the underlying deformation. When the cell membrane was separated from the cell wall by osmosis, a mechanical deformation, in the micrometer range, was observed upon excitation of the cell. The underlying mechanism of this mechanical pulse has, to date, remained elusive. Herein we report that Chara cells can undergo a pearling instability, and when the pearled fragments were excited even larger and more regular cell shape changes were observed (˜10 -100 μ m in amplitude). These transient cellular deformations were captured by a curvature model that is based on three parameters: surface tension, bending rigidity, and pressure difference across the surface. In this paper these parameters are extracted by curve-fitting to the experimental cellular shapes at rest and during excitation. This is a necessary step to identify the mechanical parameters that change during an action potential.
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Luzak, Boguslawa; Golanski, Jacek; Rozalski, Marek; Krajewska, Urszula; Olas, Beata
2010-01-01
Introduction Some polyphenolic compounds extracted from Aronia melanocarpa fruits (AM) have been reported to be cardioprotective agents. In this study we evaluated the ability of AM extract to increase the efficacy of human umbilical vein endothelial cells (HUVECs) to inhibit platelet functions in vitro. Material and methods This study encompasses two models of monitoring platelet reactivity: optical aggregation and platelet degranulation (monitored as the surface CD62P expression) in PRP upon the stimulation with ADP. Results We observed that only at low concentrations (5 µg/ml) did AM extract significantly improve antiplatelet action of HUVECs towards ADP-activated platelets in the aggregation test. Conclusions It is concluded that the potentiating effect of AM extract on the endothelial cell-mediated inhibition of platelet aggregation clearly depends on the used concentrations of Aronia-derived active compounds. Therefore, despite these encouraging preliminary outcomes on the beneficial effects of AM extract polyphenols, more profound dose-effect studies should certainly be considered before the implementation of Aronia-originating compounds in antiplatelet therapy and the prevention of cardiovascular diseases. PMID:22371737
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Yingngam, Bancha; Monschein, Marlene; Brantner, Adelheid
2014-09-01
To optimize the processing parameters for phenolic compounds extracted from Cratoxylum formosum ssp. formosum leaves using an ultrasound-assisted extraction and to evaluate its protective ability against H2O2-induced cell death. The influence of three independent variables including ethanol concentration (%), extraction temperature (°C) and extraction time (min) on the extraction yield of phenolic compounds were optimized using a central composite design-based response surface methodology. The obtained extract was assessed for its antioxidant activity by DPPH(•) and ABTS(•)(+) methods. Cellular protective ability against H2O2-induced cell death was evaluated on HEK293 cells using the MTT assay. The optimal conditions to achieve maximal yields of phenolic compounds were ethanol concentration of 50.33% (v/v), temperature of 65 °C, and extractiontion time of 15 min. The yield of phenolic compounds was (40.00±1.00) mg gallic acid equivalent/g dry powder which matched well with the values predicted from the proposed model. These conditions resulted in a higher efficiency concerning the extraction of phenolics compared to a conventional heat reflux extraction by providing shorter extraction time and reduced energy consumption. 5-O-caffeoylquinic acid identified by high performance liquid chromatography-diode array detector-electron spin ionization-mass spectrometry was the major compound in the obtained extract [(41.66±0.07) mg/g plant extract]. The obtained extract showed a strong ability to scavenge both DPPH(•) and ABTS(•)(+) free radicals and exhibited additionally good ability to protect HEK293 cells death against oxidative stress. These results indicate the suitability of ultrasound-assisted extraction for the extraction of phenolic compounds from Cratoxylum formosum ssp. formosum leaves. This phenolic-enriched extract can be used as valuable antioxidant source for health benefits. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.
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Antifilarial and Antibiotic Activities of Methanolic Extracts of Melaleuca cajuputi Flowers
Al-Abd, Nazeh M.; Nor, Zurainee Mohamed; Mansor, Marzida; Hasan, MS; Kassim, Mustafa
2016-01-01
We evaluated the activity of methanolic extracts of Melaleuca cajuputi flowers against the filarial worm Brugia pahangi and its bacterial endosymbiont Wolbachia. Anti-Wolbachia activity was measured in worms and in Aedes albopictus Aa23 cells by PCR, electron microscopy, and other biological assays. In particular, microfilarial release, worm motility, and viability were determined. M. cajuputi flower extracts were found to significantly reduce Wolbachia endosymbionts in Aa23 cells, Wolbachia surface protein, and microfilarial release, as well as the viability and motility of adult worms. Anti-Wolbachia activity was further confirmed by observation of degraded and phagocytized Wolbachia in worms treated with the flower extracts. The data provided in vitro and in vivo evidence that M. cajuputi flower extracts inhibit Wolbachia, an activity that may be exploited as an alternative strategy to treat human lymphatic filariasis. PMID:27417081
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Complete wetting of graphene by biological lipids
NASA Astrophysics Data System (ADS)
Luan, Binquan; Huynh, Tien; Zhou, Ruhong
2016-03-01
Graphene nanosheets have been demonstrated to extract large amounts of lipid molecules directly out of the cell membrane of bacteria and thus cause serious damage to the cell's integrity. This interesting phenomenon, however, is so far not well understood theoretically. Here through extensive molecular dynamics simulations and theoretical analyses, we show that this phenomenon can be categorized as a complete wetting of graphene by membrane lipids in water. A wetting-based theory was utilized to associate the free energy change during the microscopic extraction of a lipid with the spreading parameter for the macroscopic wetting. With a customized thermodynamic cycle for detailed energetics, we show that the dispersive adhesion between graphene and lipids plays a dominant role during this extraction as manifested by the curved graphene. Our simulation results suggest that biological lipids can completely wet the concave, flat or even convex (with a small curvature) surface of a graphene sheet.Graphene nanosheets have been demonstrated to extract large amounts of lipid molecules directly out of the cell membrane of bacteria and thus cause serious damage to the cell's integrity. This interesting phenomenon, however, is so far not well understood theoretically. Here through extensive molecular dynamics simulations and theoretical analyses, we show that this phenomenon can be categorized as a complete wetting of graphene by membrane lipids in water. A wetting-based theory was utilized to associate the free energy change during the microscopic extraction of a lipid with the spreading parameter for the macroscopic wetting. With a customized thermodynamic cycle for detailed energetics, we show that the dispersive adhesion between graphene and lipids plays a dominant role during this extraction as manifested by the curved graphene. Our simulation results suggest that biological lipids can completely wet the concave, flat or even convex (with a small curvature) surface of a graphene sheet. Electronic supplementary information (ESI) available: The movie showing the simulation trajectory for the extraction of lipids from the membrane. See DOI: 10.1039/C6NR00202A
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Manuel R. Pelaez-Samaniego; Vikram Yadama; Manuel Garcia-Perez; Eini Lowell; Rui Zhu; Karl Englund
2016-01-01
Hot water extraction (HWE) partially removes hemicelluloses from wood while leaving the majority of the lignin and cellulose; however, the lignin partially migrates to the inner surfaces of the cell wall where it can be deposited as a layer that is sometimes visible as droplets. This lignin-rich material was isolated via Soxhlet extraction with dichloromethane to...
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Impact of Procyanidins from Different Berries on Caspase 8 Activation in Colon Cancer.
Minker, Carole; Duban, Livine; Karas, Daniel; Järvinen, Päivi; Lobstein, Annelise; Muller, Christian D
2015-01-01
The aim of this work is to identify which proapoptotic pathway is induced in human colon cancer cell lines, in contact with proanthocyanidins extracted from various berries. Proanthocyanidins (Pcys) extracted from 11 berry species are monitored for proapoptotic activities on two related human colon cancer cell lines: SW480-TRAIL-sensitive and SW620-TRAIL-resistant. Apoptosis induction is monitored by cell surface phosphatidylserine (PS) detection. Lowbush blueberry extract triggers the strongest activity. When tested on the human monocytic cell line THP-1, blueberry Pcys are less effective for PS externalisation and DNA fragmentation is absent, highlighting a specificity of apoptosis induction in gut cells. In Pcys-treated gut cell lines, caspase 8 (apoptosis extrinsic pathway) but not caspase 9 (apoptosis intrinsic pathway) is activated after 3 hours through P38 phosphorylation (90 min), emphasizing the potency of lowbush blueberry Pcys to eradicate gut TRAIL-resistant cancer cells. We highlight here that berries Pcys, especially lowbush blueberry Pcys, are of putative interest for nutritional chemoprevention of colorectal cancer in view of their apoptosis induction in a human colorectal cancer cell lines.
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Dynamics of heat shock protein 60 in endothelial cells exposed to cigarette smoke extract
Kreutmayer, Simone Barbara; Messner, Barbara; Knoflach, Michael; Henderson, Blair; Niederegger, Harald; Böck, Günther; Van der Zee, Ruurd; Wick, Georg; Bernhard, David
2011-01-01
Heat shock protein 60 (HSP60), expressed on the surface of endothelial cells (ECs) stressed by e.g. oxidized LDL or mechanical shear, was shown to function as an auto-antigen and thus as a pro-atherosclerotic molecule. The aim of this study was to determine whether cigarette smoke chemicals can lead to the activation of the “HSP60 pathway.” It was also our aim to elucidate the dynamics of HSP60 from gene expression to endothelial surface expression and secretion. Here we show for the first time that the exposure of human umbilical vein endothelial cells (HUVECs) to cigarette smoke extract (CSE) results in an up-regulation of HSP60 mRNA. Live cell imaging analysis of a HSP60-EYFP fusion protein construct transfected into ECs revealed that mitochondrial structures collapse in response to CSE exposure. As a result, HSP60 is released from the mitochondria, transported to the cell surface, and released into the cell culture supernatant. Analysis of HSP60 in the sera of healthy young individuals exposed to secondhand smoke revealed significantly elevated levels of HSP60. Cigarette smoking is one of the most relevant risk factors for atherosclerosis. Herein, we provide evidence that cigarette smoke may initiate atherosclerosis in the sense of the “auto-immune hypothesis of atherosclerosis.” PMID:21798264
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Dynamics of heat shock protein 60 in endothelial cells exposed to cigarette smoke extract.
Kreutmayer, Simone Barbara; Messner, Barbara; Knoflach, Michael; Henderson, Blair; Niederegger, Harald; Böck, Günther; Van der Zee, Ruurd; Wick, Georg; Bernhard, David
2011-11-01
Heat shock protein 60 (HSP60), expressed on the surface of endothelial cells (ECs) stressed by e.g. oxidized LDL or mechanical shear, was shown to function as an auto-antigen and thus as a pro-atherosclerotic molecule. The aim of this study was to determine whether cigarette smoke chemicals can lead to the activation of the "HSP60 pathway." It was also our aim to elucidate the dynamics of HSP60 from gene expression to endothelial surface expression and secretion. Here we show for the first time that the exposure of human umbilical vein endothelial cells (HUVECs) to cigarette smoke extract (CSE) results in an up-regulation of HSP60 mRNA. Live cell imaging analysis of a HSP60-EYFP fusion protein construct transfected into ECs revealed that mitochondrial structures collapse in response to CSE exposure. As a result, HSP60 is released from the mitochondria, transported to the cell surface, and released into the cell culture supernatant. Analysis of HSP60 in the sera of healthy young individuals exposed to secondhand smoke revealed significantly elevated levels of HSP60. Cigarette smoking is one of the most relevant risk factors for atherosclerosis. Herein, we provide evidence that cigarette smoke may initiate atherosclerosis in the sense of the "auto-immune hypothesis of atherosclerosis." Copyright © 2011 Elsevier Ltd. All rights reserved.
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Wang, Hsiao-Ning; Liu, Tsan-Zon; Chen, Ya-Lei; Shiuan, David
2007-01-01
The protective effects of a freeze-dried extracts of vegetables and fruits (BauYuan; BY) on the hydroxyl radical-mediated DNA strand breakages and the structural integrity of human red blood cells (RBCs) were investigated. First, the supercoiled plasmid (pEGFP-C1) DNA was subjected to oxidation damage by an ascorbate-fortified Fenton reaction and the protective effects were analyzed by agarose gel electrophoresis. In the absence of BY extracts, exposure of the high-throughput .OH-generating system (Fe2+ concentration >1.0 microM) caused a complete fragmentation of DNA. Supplementation of BY extract (1 mg/mL) to the plasmid DNA prior to the exposure could prevent it significantly. In contrast, as the plasmid exposed to a low-grade .OH-generating system (Fe2+<0.1 microM), the BY extract (1 mg/mL) provided an almost complete protection. Next, the cell deformabilities were measured to assess the protection effects of various BY extracts on human erythrocytes exposed to the oxidative insults. We found that both the aqueous extract and the organic solvent-derived extracts could strongly protect human RBCs from the reactive oxygen species (ROS)-mediated decrease in the deformability indices. The results implicated that the BY extracts could effectively protect the cell membrane integrity via scavenging ROS which enabling RBCs to maintain a balance of water content and surface area to prevent the drop of cell deformability.
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Enhanced Lifetime of Polymer Solar Cells by Surface Passivation of Metal Oxide Buffer Layers.
Venkatesan, Swaminathan; Ngo, Evan; Khatiwada, Devendra; Zhang, Cheng; Qiao, Qiquan
2015-07-29
The role of electron selective interfaces on the performance and lifetime of polymer solar cells were compared and analyzed. Bilayer interfaces consisting of metal oxide films with cationic polymer modification namely poly ethylenimine ethoxylated (PEIE) were found to enhance device lifetime compared to bare metal oxide films when used as an electron selective cathode interface. Devices utilizing surface-modified metal oxide layers showed enhanced lifetimes, retaining up to 85% of their original efficiency when stored in ambient atmosphere for 180 days without any encapsulation. The work function and surface potential of zinc oxide (ZnO) and ZnO/PEIE interlayers were evaluated using Kelvin probe and Kelvin probe force microscopy (KPFM) respectively. Kelvin probe measurements showed a smaller reduction in work function of ZnO/PEIE films compared to bare ZnO films when aged in atmospheric conditions. KPFM measurements showed that the surface potential of the ZnO surface drastically reduces when stored in ambient air for 7 days because of surface oxidation. Surface oxidation of the interface led to a substantial decrease in the performance in aged devices. The enhancement in the lifetime of devices with a bilayer interface was correlated to the suppressed surface oxidation of the metal oxide layers. The PEIE passivated surface retained a lower Fermi level when aged, which led to lower trap-assisted recombination at the polymer-cathode interface. Further photocharge extraction by linearly increasing voltage (Photo-CELIV) measurements were performed on fresh and aged samples to evaluate the field required to extract maximum charges. Fresh devices with a bare ZnO cathode interlayer required a lower field than devices with ZnO/PEIE cathode interface. However, aged devices with ZnO required a much higher field to extract charges while aged devices with ZnO/PEIE showed a minor increase compared to the fresh devices. Results indicate that surface modification can act as a suitable passivation layer to suppress oxidation in metal oxide thin films for enhanced lifetime in inverted organic solar cells.
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White, Paul B; Wang, Tuo; Park, Yong Bum; Cosgrove, Daniel J; Hong, Mei
2014-07-23
Polysaccharide-rich plant cell walls are hydrated under functional conditions, but the molecular interactions between water and polysaccharides in the wall have not been investigated. In this work, we employ polarization transfer solid-state NMR techniques to study the hydration of primary-wall polysaccharides of the model plant, Arabidopsis thaliana. By transferring water (1)H polarization to polysaccharides through distance- and mobility-dependent (1)H-(1)H dipolar couplings and detecting it through polysaccharide (13)C signals, we obtain information about water proximity to cellulose, hemicellulose, and pectins as well as water mobility. Both intact and partially extracted cell wall samples are studied. Our results show that water-pectin polarization transfer is much faster than water-cellulose polarization transfer in all samples, but the extent of extraction has a profound impact on the water-polysaccharide spin diffusion. Removal of calcium ions and the consequent extraction of homogalacturonan (HG) significantly slowed down spin diffusion, while further extraction of matrix polysaccharides restored the spin diffusion rate. These trends are observed in cell walls with similar water content, thus they reflect inherent differences in the mobility and spatial distribution of water. Combined with quantitative analysis of the polysaccharide contents, our results indicate that calcium ions and HG gelation increase the amount of bound water, which facilitates spin diffusion, while calcium removal disrupts the gel and gives rise to highly dynamic water, which slows down spin diffusion. The recovery of spin diffusion rates after more extensive extraction is attributed to increased water-exposed surface areas of the polysaccharides. Water-pectin spin diffusion precedes water-cellulose spin diffusion, lending support to the single-network model of plant primary walls in which a substantial fraction of the cellulose surface is surrounded by pectins.
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Liu, Benguo; Liu, Feng; Chen, Chungang; Gao, Han
2010-12-01
In this study, supercritical carbon dioxide extraction of ethyl p-methoxycinnamate from Kaempferia galanga L. rhizome and its apoptotic induction in human HepG2 cells are reported for the first time. By using supercritical carbon dioxide extraction, the yield of ethyl p-methoxycinnamate identified by gas chromatography mass spectrometry (GC-MS) was as high as 2.5% with respect to the raw materials. In the anticancer assay, it was found that ethyl p-methoxycinnamate could inhibit the proliferation of the human hepatocellular liver carcinoma HepG2 cell line in a dose-dependent manner and induce the significant increase of the subG0 cell population. After treatment with ethyl p-methoxycinnamate, phosphatidylserine of HepG2 cells could significantly translocate to the surface of the membrane. The increase of an early apoptotic population was observed by both annexin-fluorescein isothiocyanate (FITC) and propidium iodide (PI) staining. It was concluded that ethyl p-methoxycinnamate not only induced cells to enter into apoptosis, but also affected the progress of the cell cycle.
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Jang, Mi; Jeong, Seung-Weon; Kim, Bum-Keun; Kim, Jong-Chan
2015-01-01
Plant extracts have been used as herbal medicines to treat a wide variety of human diseases. We used response surface methodology (RSM) to optimize the Artemisia capillaris Thunb. extraction parameters (extraction temperature, extraction time, and ethanol concentration) for obtaining an extract with high anti-inflammatory activity at the cellular level. The optimum ranges for the extraction parameters were predicted by superimposing 4-dimensional response surface plots of the lipopolysaccharide- (LPS-) induced PGE2 and NO production and by cytotoxicity of A. capillaris Thunb. extracts. The ranges of extraction conditions used for determining the optimal conditions were extraction temperatures of 57–65°C, ethanol concentrations of 45–57%, and extraction times of 5.5–6.8 h. On the basis of the results, a model with a central composite design was considered to be accurate and reliable for predicting the anti-inflammation activity of extracts at the cellular level. These approaches can provide a logical starting point for developing novel anti-inflammatory substances from natural products and will be helpful for the full utilization of A. capillaris Thunb. The crude extract obtained can be used in some A. capillaris Thunb.-related health care products. PMID:26075271
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Preparation and analysis of fetal liver extracts.
Zwicky, C; Gerber, S; Gasparini, D; Forestier, F; Hohlfeld, P; Tissot, J D; Schneider, P
2000-09-01
The aim of this work is to describe the techniques that have been used for preparation and analysis of whole fetal liver extracts destined for in utero transplantation. Nine fetal livers between 12 and 17 weeks of gestation were prepared: cell counts and assessment of the hematopoietic cell viability were performed on cell suspensions. Hepatocytes represented 40 to 80% of the whole cell population. The remaining cells were constituted by hematopoietic cells (mainly erythroblasts), as well as by endothelial cells. The latter expressed CD34 on their surface, interfering with the assessment of CD34+ hematopoietic cells by flow cytometry. Direct visual morphologic control using alkaline phosphatase anti-alkaline phosphatase techniques was needed to differentiate hematopoietic from extra-hematopoietic CD34+ cells. Between 3.0 and 34.6 x 10(6) CD34+ viable hematopoietic cells were collected per fetal liver. Adequate differentiation of these cells into burst-forming units erythroid (BFU-E), colony-forming units granulocyte-macrophage (CFU-GM), and colony-forming units granulocyte erythroid macrophage megakaryocyte (CFU-GEMM) has been shown for each sample in clonogeneic cultures. In conclusion, fetal liver is a potential source of hematopoietic stem cells. Their numeration, based on the presence of CD34, is hampered by the expression of this antigen on other cells contained in the liver cell extract, in particular endothelial cells.
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Lee, Jee Bum; Li, Ying; Choi, Ji Suk; Lee, Hyo Seok
2016-01-01
Purpose. To investigate the therapeutic effects of topical administration of antioxidant medicinal plant extracts in a mouse model of experimental dry eye (EDE). Methods. Eye drops containing balanced salt solution (BSS) or 0.001%, 0.01%, and 0.1% extracts were applied for the treatment of EDE. Tear volume, tear film break-up time (BUT), and corneal fluorescein staining scores were measured 10 days after desiccating stress. In addition, we evaluated the levels of interleukin- (IL-) 1β, tumor necrosis factor- (TNF-) α, IL-6, interferon- (IFN-) γ, and IFN-γ associated chemokines, percentage of CD4+C-X-C chemokine receptor type 3 positive (CXCR3+) T cells, goblet cell density, number of 4-hydroxy-2-nonenal (4-HNE) positive cells, and extracellular reactive oxygen species (ROS) production. Results. Compared to the EDE and BSS control groups, the mice treated with topical application of the 0.1% extract showed significant improvements in all clinical parameters, IL-1β, IL-6, TNF-α, and IFN-γ levels, percentage of CD4+CXCR3+ T cells, goblet cell density, number of 4-HNE-positive cells, and extracellular ROS production (P < 0.05). Conclusions. Topical application of 0.1% medicinal plant extracts improved clinical signs, decreased inflammation, and ameliorated oxidative stress marker and ROS production on the ocular surface of the EDE model mice. PMID:27313829
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Effects of phytoestrogens derived from soy bean on expression of adhesion molecules on HUVEC.
Andrade, C M de; Sá, M F Silva de; Toloi, M R Torqueti
2012-04-01
The risks of hormone replacement therapy have led to a search for new alternatives such as phytoestrogens, plant compounds with estrogen-like biological activity. Isoflavones are the phytoestrogens most extensively studied and can be found in soybean, red clover and other plants. Due to this estrogen-like activity, phytoestrogens can have some effect on atherosclerosis. Human umbilical vein endothelial cells (HUVEC) have been extensively used to study the biology and pathobiology of human endothelial cells and most of the knowledge acquired is due to experiments with cultures of these cells. To evaluate the effects of the phytoestrogen extracts from Glycine max soy bean, genistein, formononetin, biochanin A and daidzein, as well as a mixture of these extracts (Mix), on expression of adhesion molecules, VCAM-1, ICAM-1 and E-selectin, by endothelial cell HUVEC, stimulated with lipopolysaccharide. HUVEC were cultured in medium EBM(2), pretreated with isoflavones for 24 and 48 h and then stimulated with lipopolysaccharide; in addition, isoflavones were added, after stimulation by lipopolysaccharide, to HUVEC. We evaluated the production of VCAM-1, ICAM-1 and E-selectin on cell surface, by cell-based enzyme immunoassay, and of sVCAM-1, sICAM-1 and sE-selectin in culture supernatant, by ELISA. Genistein, formononetin, biochanin A and daidzein, as well as the Mix were able to reduce VCAM-1, ICAM-1 and E-selectin on cell surface and in culture supernatant. Conclusion Isoflavones extracted from Glycine max soy bean, in vitro, presented antiatherogenic effects, reducing the expression of adhesion molecules and acting as preventive agents as well as therapeutic agents.
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B-cell acquisition of antigen: Sensing the surface.
Knight, Andrew M
2015-06-01
B-cell antigen receptor (BCR) recognition and acquisition of antigen by B cells is the essential first step in the generation of effective antibody responses. As B-cell-mediated antigen presentation is also believed to play a significant role in the activation of CD4(+) Th-cell responses, considerable effort has focused on clarifying the nature of antigen/BCR interactions. Following earlier descriptions of interactions of soluble antigens with the BCR, it is now clear that B cells also recognize, physically extract and present antigens that are tethered to, or integral components of, the surfaces or extracellular matrix of other cells. In this issue of the European Journal of Immunology, Zeng et al. [Eur. J. Immunol. 2015. 45: XXXX-XXXX] examine how the physical property or "stiffness" of the surface displaying antigens to B cells influences the B-cell response. This commentary reports that antigen tethered on "less stiff" surfaces induces increased B-cell activation and antibody responses. I then infer how "sensing the surface" by B cells may represent a new component of the immune system's ability to detect "damage," and how this understanding may influence approaches to clinical therapies where immune activity is either unwanted or desired. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Mu, S; Tee, B C; Emam, H; Zhou, Y; Sun, Z
2018-04-06
Impaired bone formation of the buccal alveolar plate after tooth extraction during adolescence increases the difficulty of future implant restoration. This study was undertaken to assess the feasibility and efficacy of transplanting autogenous scaffold-free culture-expanded mesenchymal stem cell (MSC) sheets to the buccal alveolar bone surface to stimulate local bone growth. Mandibular bone marrow was aspirated from 3-month-old pigs (n = 5), from which MSCs were isolated and culture expanded. Triple-layer MSC sheets were then fabricated using temperature-responsive tissue culture plates. One month after bone marrow aspirations, the same pigs underwent bilateral extraction of mandibular primary molars, immediately followed by transplantation of 3 autogenous triple-layer MSC sheets on to the subperiosteal buccal alveolar surface of 1 randomly chosen side. The contralateral side (control) underwent the same periosteal reflection surgery without receiving MSC sheet transplantation. Six weeks later, the animals were killed and specimens from both sides were immediately harvested for radiographic and histological analysis. Buccal alveolar bone thickness, tissue mineral density (TMD), mineral apposition and bone volume fraction (BV/TV) were quantified and compared between the MSC sheet and control sides using paired t-tests. Triple-layer MSC sheets were reliably fabricated and the majority of cells remained vital before transplantation. The thickness of buccal bone tended to increase with MSC sheet transplantation (P = .18), with 4 of 5 animals showing an average of 1.82 ± 0.73 mm thicker bone on the MSC sheet side than the control side. After being normalized by the TMD of intracortical bone, the TMD of surface cortical bone was 0.5-fold higher on the MSC sheet side than the control side (P < .05). Likewise, the BV/TV measurements of the buccal surface region were also 0.4-fold higher on the MSC sheet side than the control side (P < .05) after being normalized by measurements from the intracortical region. Mineral apposition measurements were not different between the 2 sides. Mandibular marrow-derived MSCs can be fabricated into cell sheets and autogenous transplantation of MSC sheets onto the subperiosteal buccal alveolar bone surface at the tooth-extraction site may increase local bone density. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Olaokun, Oyinlola O; McGaw, Lyndy J; Awouafack, Maurice D; Eloff, Jacobus N; Naidoo, Vinny
2014-07-28
Some Ficus species have been used in traditional African medicine in the treatment of diabetes. The antidiabetic potential of certain species has been confirmed in vivo but the mechanism of activity remains uncertain. The aim was to investigate the hypoglycaemic potential of ten Ficus species focussing on glucose uptake, insulin secretion and the possible mechanism of hypoglycaemic activity. The dried and ground leaves of ten Ficus species were extracted with acetone. The dried acetone extract was reconstituted with DMSO to a concentration of 100 mg/ml which was then serially diluted and used to assay for glucose uptake in muscle, fat and liver cells, and insulin secretion in pancreatic cells. Only the F. lutea extract was able to modulate glucose metabolism. In comparison to insulin in the primary muscle cells, the glucose uptake ability of the extract was 33% as effective. In the hepatoma cell line, the extract was as effective as metformin in decreasing extracellular glucose concentration by approximately 20%. In the pancreatic insulin secretory assay, the extract was 4 times greater in its secretory activity than commercial glibenclamide. With F. lutea extract significantly increasing glucose uptake in the primary muscle cells, primary fat cells, C2C12 muscle and H-4-II-E liver cells, the extract may act by increasing the activity of cell surface glucose transporters. When the 3T3-L1 pre-adipocytes were compared to the primary muscle, primary fat and C2C12 cells, the differences in the former's ability to transport glucose into the cell may be due to the absence of the GLUT4 transporter, which on activation via the insulin receptor decreases extracellular glucose concentrations. Because the pre-adipocytes failed to show any active increase in glucose uptake, the present effect has to be linked to the absence of the GLUT4 transporter. Only F. lutea possessed substantial in vitro activity related to glucose metabolism. Based on the effect produced in the various cell types, F. lutea also appears to be a partial agonist/antagonist of the insulin cell membrane receptor. While the clinical effectiveness of F. lutea is not known, this plant species does possess the ability to modify glucose metabolism.
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Flow-induced detachment of red blood cells adhering to surfaces by specific antigen-antibody bonds.
Xia, Z; Goldsmith, H L; van de Ven, T G
1994-04-01
Fixed spherical swollen human red blood cells of blood type B adhering on a glass surface through antigen-antibody bonds to monoclonal mouse antihuman IgM, adsorbed or covalently linked on the surface, were detached by known hydrodynamic forces created in an impinging jet. The dynamic process of detachment of the specifically bound cells was recorded and analyzed. The fraction of adherent cells remaining on the surface decreased with increasing hydrodynamic force. For an IgM coverage of 0.26%, a tangential force on the order of 100 pN was able to detach almost all of the cells from the surface within 20 min. After a given time of exposure to hydrodynamic force, the fraction of adherent cells remaining increased with time, reflecting an increase in adhesion strength. The characteristic time for effective aging was approximately 4 h. Results from experiments in which the adsorbed antibody molecules were immobilized through covalent coupling and from evanescent wave light scattering of adherent cells, imply that deformation of red cells at the contact area was the principal cause for aging, rather than local clustering of the antibody through surface diffusion. Experiments with latex beads specifically bound to red blood cells suggest that, instead of breaking the antigen-antibody bonds, antigen molecules were extracted from the cell membrane during detachment.
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MorphoGraphX: A platform for quantifying morphogenesis in 4D.
Barbier de Reuille, Pierre; Routier-Kierzkowska, Anne-Lise; Kierzkowski, Daniel; Bassel, George W; Schüpbach, Thierry; Tauriello, Gerardo; Bajpai, Namrata; Strauss, Sören; Weber, Alain; Kiss, Annamaria; Burian, Agata; Hofhuis, Hugo; Sapala, Aleksandra; Lipowczan, Marcin; Heimlicher, Maria B; Robinson, Sarah; Bayer, Emmanuelle M; Basler, Konrad; Koumoutsakos, Petros; Roeder, Adrienne H K; Aegerter-Wilmsen, Tinri; Nakayama, Naomi; Tsiantis, Miltos; Hay, Angela; Kwiatkowska, Dorota; Xenarios, Ioannis; Kuhlemeier, Cris; Smith, Richard S
2015-05-06
Morphogenesis emerges from complex multiscale interactions between genetic and mechanical processes. To understand these processes, the evolution of cell shape, proliferation and gene expression must be quantified. This quantification is usually performed either in full 3D, which is computationally expensive and technically challenging, or on 2D planar projections, which introduces geometrical artifacts on highly curved organs. Here we present MorphoGraphX ( www.MorphoGraphX.org), a software that bridges this gap by working directly with curved surface images extracted from 3D data. In addition to traditional 3D image analysis, we have developed algorithms to operate on curved surfaces, such as cell segmentation, lineage tracking and fluorescence signal quantification. The software's modular design makes it easy to include existing libraries, or to implement new algorithms. Cell geometries extracted with MorphoGraphX can be exported and used as templates for simulation models, providing a powerful platform to investigate the interactions between shape, genes and growth.
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Impact of Procyanidins from Different Berries on Caspase 8 Activation in Colon Cancer
Minker, Carole; Duban, Livine; Karas, Daniel; Järvinen, Päivi; Lobstein, Annelise; Muller, Christian D.
2015-01-01
Scope. The aim of this work is to identify which proapoptotic pathway is induced in human colon cancer cell lines, in contact with proanthocyanidins extracted from various berries. Methods and Results. Proanthocyanidins (Pcys) extracted from 11 berry species are monitored for proapoptotic activities on two related human colon cancer cell lines: SW480-TRAIL-sensitive and SW620-TRAIL-resistant. Apoptosis induction is monitored by cell surface phosphatidylserine (PS) detection. Lowbush blueberry extract triggers the strongest activity. When tested on the human monocytic cell line THP-1, blueberry Pcys are less effective for PS externalisation and DNA fragmentation is absent, highlighting a specificity of apoptosis induction in gut cells. In Pcys-treated gut cell lines, caspase 8 (apoptosis extrinsic pathway) but not caspase 9 (apoptosis intrinsic pathway) is activated after 3 hours through P38 phosphorylation (90 min), emphasizing the potency of lowbush blueberry Pcys to eradicate gut TRAIL-resistant cancer cells. Conclusion. We highlight here that berries Pcys, especially lowbush blueberry Pcys, are of putative interest for nutritional chemoprevention of colorectal cancer in view of their apoptosis induction in a human colorectal cancer cell lines. PMID:26180579
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Koike, Eiko; Kobayashi, Takahiro
2005-12-15
We hypothesized that diesel exhaust particles (DEP) induce the activation of antigen-presenting cells (APC) in lung. The present study was designed to clarify the following about DEP: (1) whether it affects the expression of Ia and B7 molecules in alveolar macrophages (AM) as a mature cell or in peripheral blood monocytes (PBM) as an immature cell (2) if it affects the antigen-presenting (AP) activity of PBM (3) what component of DEP is responsible for the effects, and (4) whether the effect of DEP is related to oxidative stress. DEP was extracted with methylene chloride. Cells were exposed to whole DEP,more » organic extract, or residual particles for 24 h. Cell-surface molecules were measured by flow cytometry. AP activity was assessed by antigen-specific T cell proliferation. Whole DEP or organic extract significantly increased the expression of Ia and B7 molecules on PBM but not on AM. No significant effect of residual particles was observed. A low concentration of organic extract also increased the AP activity of PBM. When the induction of an antioxidative enzyme was assessed, heme oxygenase-1 protein was found to be significantly increased by exposure to whole DEP, and the organic extract was more effective than the residual particles. Furthermore, the organic extract-induced expression of Ia antigen on PBM was reduced by the addition of an antioxidative agent. These results suggest that DEP may act on immature APC and enhance their AP activity and that the action contributing to oxidative stress may be mediated by organic compounds of DEP.« less
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Method and Apparatus for Automated Isolation of Nucleic Acids from Small Cell Samples
NASA Technical Reports Server (NTRS)
Sundaram, Shivshankar; Prabhakarpandian, Balabhaskar; Pant, Kapil; Wang, Yi
2014-01-01
RNA isolation is a ubiquitous need, driven by current emphasis on microarrays and miniaturization. With commercial systems requiring 100,000 to 1,000,000 cells for successful isolation, there is a growing need for a small-footprint, easy-to-use device that can harvest nucleic acids from much smaller cell samples (1,000 to 10,000 cells). The process of extraction of RNA from cell cultures is a complex, multi-step one, and requires timed, asynchronous operations with multiple reagents/buffers. An added complexity is the fragility of RNA (subject to degradation) and its reactivity to surface. A novel, microfluidics-based, integrated cartridge has been developed that can fully automate the complex process of RNA isolation (lyse, capture, and elute RNA) from small cell culture samples. On-cartridge cell lysis is achieved using either reagents or high-strength electric fields made possible by the miniaturized format. Traditionally, silica-based, porous-membrane formats have been used for RNA capture, requiring slow perfusion for effective capture. In this design, high efficiency capture/elution are achieved using a microsphere-based "microfluidized" format. Electrokinetic phenomena are harnessed to actively mix microspheres with the cell lysate and capture/elution buffer, providing important advantages in extraction efficiency, processing time, and operational flexibility. Successful RNA isolation was demonstrated using both suspension (HL-60) and adherent (BHK-21) cells. Novel features associated with this development are twofold. First, novel designs that execute needed processes with improved speed and efficiency were developed. These primarily encompass electric-field-driven lysis of cells. The configurations include electrode-containing constructs, or an "electrode-less" chip design, which is easy to fabricate and mitigates fouling at the electrode surface; and the "fluidized" extraction format based on electrokinetically assisted mixing and contacting of microbeads in a shape-optimized chamber. A secondary proprietary feature is in the particular layout integrating these components to perform the desired operation of RNA isolation. Apart from a novel functional capability, advantages of the innovation include reduced or eliminated use of toxic reagents, and operator-independent extraction of RNA.
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Chan, W Y; Chian, K S; Tan, M J
2013-12-01
Amorphous zinc-rich Mg-Zn-Ca alloys have exhibited good tissue compatibility and low hydrogen evolution in vivo. However, suboptimal cell-surface interaction on magnesium alloy surface observed in vitro could lead to reduced integration with host tissue for regenerative purpose. This study aims to improve cell-surface interaction of amorphous Mg67Zn28Ca5 alloy by coating a gelatin layer by electrospinning. Coated/uncoated alloys were immersed and extracted for 3 days under different CO2. The immersion results showed that pH and metal ion release in the alloy extracts were affected by gelatin coating and CO2, suggesting their roles in alloy biocorrosion and a mechanism has been proposed for the alloy-CO2 system with/without coating. Cytotoxicity results are evident that gelatin-coated alloy with 2-day crosslinking not only exhibited no indirect cytotoxicity, but also supported attachment of L929 and MG63 cell lines around/on the alloy with high viability. Therefore, amorphous Mg67Zn28Ca5 alloy coated with gelatin by electrospinning technique provides a useful method to improve alloy biocompatibility. © 2013 Elsevier B.V. All rights reserved.
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Vinogradov, E; Sadovskaya, I; Cornelissen, A; van Sinderen, D
2015-09-02
Lactobacilli are valuable strains for commercial (functional) food fermentations. Their cell surface-associated polysaccharides (sPSs) possess important functional properties, such as acting as receptors for bacteriophages (bacterial viruses), influencing autolytic characteristics and providing protection against antimicrobial peptides. The current report provides an elaborate molecular description of several surface carbohydrates of Lactobacillus delbrueckii subsp. bulgaricus strain 17. The cell surface of this strain was shown to contain short chain poly(glycerophosphate) teichoic acids and at least two different sPSs, designated here as sPS1 and sPS2, whose chemical structures were examined by 2D nuclear magnetic resonance spectroscopy and methylation analysis. Neutral branched sPS1, extracted with n-butanol, was shown to be composed of hexasaccharide repeating units (-[α-d-Glcp-(1-3)-]-4-β-l-Rhap2OAc-4-β-d-Glcp-[α-d-Galp-(1-3)]-4-α-Rhap-3-α-d-Galp-), while the major component of the TCA-extracted sPS2 was demonstrated to be a linear d-galactan with the repeating unit structure being (-[Gro-3P-(1-6)-]-3-β-Galf-3-α-Galp-2-β-Galf-6-β-Galf-3-β-Galp-). Copyright © 2015 Elsevier Ltd. All rights reserved.
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Dazzo, F B; Hubbell, D H
1975-01-01
Cross-reactive antigens of clover roots and Rhizobium trifolii were detected on their cell surfaces by tube agglutination, immunofluorescent, and radioimmunoassay techniques. Anti-clover root antiserum had a higher agglutinating titer with infective strains of R. trifolii than with noninfective strains. The root antiserum previously adsorbed with noninfective R. trifolii cells remained reactive only with infective cells, including infective revertants. When adsorbed with infective cells, the root antiserum was reactive with neither infective nor noninfective cells. Other Rhizobium species incapable of infecting clover did not demonstrate surface antigens cross-reactive with clover. Radioimmunoassay indicated twice as much antigenic cross-reactivity of clover roots and R. trifolii 403 (infective) than R. trifolii Bart A (noninfective). Immunofluorescence with anti-R. trifolii (infective) antiserum was detected on the exposed surface of the root epidermal cells and diminished at the root meristem. The immunofluorescent crossreaction on clover roots was totally removed by adsorption of anti-R. trifolii (infective) antiserum with encapsulated infective cells but not with noninfective cells. The cross-reactive capsular antigens from R. trifolii strains were extracted and purified. The ability of these antigens to induce clover root hair deformation was much greater when they were obtained from the infective than noninfective strains. The cross-reactive capsular antigen of R. trifolii 403 was characterized as a high-molecular-weight (greater than 4.6 times 10(6) daltons), beta-linked, acidic heteropolysaccharide containing 2-deoxyglucose, galactose, glucose, and glucuronic acid. A soluble, nondialyzable, substance (clover lectin) capable of binding to the cross-reactive antigen and agglutinating only infective cells of R. trifolii was extracted from white clover seeds. This lectin was sensitive to heat, Pronase, and trypsin. inhibition studies indicated that 2-deoxyglucose was the most probable haptenic determinant of the cross-reactive capsular antigen capable of binding to the root antiserum and the clover lectin. A model is proposed suggesting the preferential adsorption of infective versus noninfective cells of R. trifolii on the surface of clover roots by a cross-bridging of their common surface antigens with a multivalent clover lectin. Images PMID:55100
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Chatterjee, Anirban; Mirer, Paul L; Zaldivar Santamaria, Elvira; Klapperich, Catherine; Sharon, Andre; Sauer-Budge, Alexis F
2010-06-01
The life science and healthcare communities have been redefining the importance of ribonucleic acid (RNA) through the study of small molecule RNA (in RNAi/siRNA technologies), micro RNA (in cancer research and stem cell research), and mRNA (gene expression analysis for biologic drug targets). Research in this field increasingly requires efficient and high-throughput isolation techniques for RNA. Currently, several commercial kits are available for isolating RNA from cells. Although the quality and quantity of RNA yielded from these kits is sufficiently good for many purposes, limitations exist in terms of extraction efficiency from small cell populations and the ability to automate the extraction process. Traditionally, automating a process decreases the cost and personnel time while simultaneously increasing the throughput and reproducibility. As the RNA field matures, new methods for automating its extraction, especially from low cell numbers and in high throughput, are needed to achieve these improvements. The technology presented in this article is a step toward this goal. The method is based on a solid-phase extraction technology using a porous polymer monolith (PPM). A novel cell lysis approach and a larger binding surface throughout the PPM extraction column ensure a high yield from small starting samples, increasing sensitivity and reducing indirect costs in cell culture and sample storage. The method ensures a fast and simple procedure for RNA isolation from eukaryotic cells, with a high yield both in terms of quality and quantity. The technique is amenable to automation and streamlined workflow integration, with possible miniaturization of the sample handling process making it suitable for high-throughput applications.
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NASA Astrophysics Data System (ADS)
Shanmugam, Vinoth; Manoharan, Subbaiah; Anandan, Sambandam; Murugan, Ramaswamy
2013-03-01
Natural dyes extracted from fruits of ivy gourd and flowers of red frangipani were used as sensitizers to fabricate dye sensitized solar cells (DSSCs). The UV-Vis absorption spectroscopy, Fourier transform infrared (FTIR), Fourier transform Raman (FT-Raman) and liquid chromatography-mass spectrometry (LC-MS) studies indicated the presence of β-carotene in the fruits of ivy gourd and anthocyanins in the flowers of red frangipani. The extract of the flowers of red frangipani exhibits higher photosensitized performance compared to the fruits of ivy gourd and this is due to the better charge transfer between the dyes of flowers of red frangipani and the TiO2 photoanode surface.
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Xie, Shao-Hua; Liu, Ai-Lin; Chen, Yan-Yan; Zhang, Li; Zhang, Hui-Juan; Jin, Bang-Xiong; Lu, Wen-Hong; Li, Xiao-Yan; Lu, Wen-Qing
2010-04-01
Because of the daily and life-long exposure to disinfection by-products formed during drinking water treatment, potential adverse human health risk of drinking water disinfection is of great concern. Toxicological studies have shown that drinking water treatment increases the genotoxicity of surface water. Drinking water treatment is comprised of different potabilization steps, which greatly influence the levels of genotoxic products in the surface water and thus may alter the toxicity and genotoxicity of surface water. The aim of the present study was to understand the influence of specific steps on toxicity and genotoxicity during the treatment of surface water in a water treatment plant using liquid chlorine as the disinfectant in China. An integrated approach of the comet and oxidative stress assays was used in the study, and the results showed that both the prechlorination and postchlorination steps increased DNA damage and oxidative stress caused by water extracts in human derived L-02 cells while the tube settling and filtration steps had the opposite effect. This research also highlighted the usefulness of an integrated approach of the comet and oxidative stress assays in evaluating the genotoxicity of surface water during drinking water treatment. Copyright 2009 Wiley-Liss, Inc.
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The Effect of Ag and Ag+N Ion Implantation on Cell Attachment Properties
DOE Office of Scientific and Technical Information (OSTI.GOV)
Urkac, Emel Sokullu; Oztarhan, Ahmet; Gurhan, Ismet Deliloglu
2009-03-10
Implanted biomedical prosthetic devices are intended to perform safely, reliably and effectively in the human body thus the materials used for orthopedic devices should have good biocompatibility. Ultra High Molecular Weight Poly Ethylene (UHMWPE) has been commonly used for total hip joint replacement because of its very good properties. In this work, UHMWPE samples were Ag and Ag+N ion implanted by using the Metal-Vapor Vacuum Arc (MEVVA) ion implantation technique. Samples were implanted with a fluency of 1017 ion/cm2 and extraction voltage of 30 kV. Rutherford Backscattering Spectrometry (RBS) was used for surface studies. RBS showed the presence of Agmore » and N on the surface. Cell attachment properties investigated with model cell lines (L929 mouse fibroblasts) to demonstrate that the effect of Ag and Ag+N ion implantation can favorably influence the surface of UHMWPE for biomedical applications. Scanning electron microscopy (SEM) was used to demonstrate the cell attachment on the surface. Study has shown that Ag+N ion implantation represents more effective cell attachment properties on the UHMWPE surfaces.« less
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Extracting archaeal populations from iron oxidizing systems
NASA Astrophysics Data System (ADS)
Whitmore, L. M.; Hutchison, J.; Chrisler, W.; Jay, Z.; Moran, J.; Inskeep, W.; Kreuzer, H.
2013-12-01
Unique environments in Yellowstone National Park offer exceptional conditions for studying microorganisms in extreme and constrained systems. However, samples from some extreme systems often contain inorganic components that pose complications during microbial and molecular analysis. Several archaeal species are found in acidic, geothermal ferric-oxyhydroxide mats; these species have been shown to adhere to mineral surfaces in flocculated colonies. For optimal microbial analysis, (microscopy, flow cytometry, genomic extractions, proteomic analysis, stable isotope analysis, and others), improved techniques are needed to better facilitate cell detachment and separation from mineral surfaces. As a requirement, these techniques must preserve cell structure while simultaneously minimizing organic carryover to downstream analysis. Several methods have been developed for removing sediments from mixed prokaryotic populations, including ultra-centrifugation, nycodenz gradient, sucrose cushions, and cell straining. In this study we conduct a comparative analysis of mechanisms used to detach archaeal cell populations from the mineral interface. Specifically, we evaluated mechanical and chemical approaches for cell separation and homogenization. Methods were compared using confocal microscopy, flow cytometry analyses, and real-time PCR detection. The methodology and approaches identified will be used to optimize biomass collection from environmental specimens or isolates grown with solid phases.
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Micromechanical and surface adhesive properties of single saccharomyces cerevisiae cells
NASA Astrophysics Data System (ADS)
Farzi, Bahman; Cetinkaya, Cetin
2017-09-01
The adhesion and mechanical properties of a biological cell (e.g. cell membrane elasticity and adhesiveness) are often strong indicators for the state of its health. Many existing techniques for determining mechanical properties of cells require direct physical contact with a single cell or a group of cells. Physical contact with the cell can trigger complex mechanotransduction mechanisms, leading to cellular responses, and consequently interfering with measurement accuracy. In the current work, based on ultrasonic excitation and interferometric (optical) motion detection, a non-contact method for characterizing the adhesion and mechanical properties of single cells is presented. It is experimentally demonstrated that the rocking (rigid body) motion and internal vibrational resonance frequencies of a single saccharomyces cerevisiae (SC) (baker’s yeast) cell can be acquired with the current approach, and the Young’s modulus and surface tension of the cell membrane as well as surface adhesion energy can be extracted from the values of these acquired resonance frequencies. The detected resonance frequency ranges for single SC cells include a rocking (rigid body) frequency of 330 ± 70 kHz and two breathing resonance frequencies of 1.53 ± 0.12 and 2.02 ± 0.31 MHz. Based on these values, the average work-of-adhesion of SC cells on a silicon substrate in aqueous medium is extracted, for the first time, as WASC-Si=16.2+/- 3.8 mJ {{m}-2} . Similarly, the surface tension and the Young’s modulus of the SC cell wall are predicted as {{σ }SC}=0.16+/- 0.02 N {{m}-1} and {{E}SC}= 9.20 ± 2.80 MPa, respectively. These results are compared to those reported in the literature by utilizing various methods, and good agreements are found. The current approach eliminates the measurement inaccuracies associated with the physical contact. Exciting and detecting cell dynamics at micro-second time-scales is significantly faster than the currently known metabolistic response times of cells (milliseconds to seconds), thus, it has the potential to decouple metabolistic and mechanotransduction effects from external stimuli and to operate at high throughput rates.
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Heyman, Leali; Houri-Haddad, Yael; Heyman, Samuel N; Ginsburg, Isaac; Gleitman, Yossi; Feuerstein, Osnat
2017-08-10
The common usage of chewing sticks prepared from Neem tree (Azadirachta indica) in India suggests its potential efficacy in periodontal diseases. The objective of this study is to explore the antibacterial effects of Neem leaf extract on the periodontophatic bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, and its antioxidant capacities alone and in combination with bacteria and polycationic peptides that may be at the site of inflammation. Neem leaf extract was prepared by ethanol extraction. The growth kinetics of P. gingivalis and F. nucleatum under anaerobic conditions in the presence of Neem leaf extract were measured. Broth microdilution test was used to determine the Minimal Inhibitory Concentration (MIC) of Neem leaf extract against each bacterial strain. The effect of Neem leaf extract on the coaggregation of the bacteria was assessed by a visual semi-quantitative assay. The antioxidant capacities of Neem leaf extract alone and in combination with bacteria, with the addition of red blood cells or the polycationic peptides chlorhexidine and lisozyme, were determined using a chemiluminescence assay. Neem leaf extract showed prominent dose-dependent antibacterial activity against P. gingivalis, however, had no effect on the growth of F. nucleatum nor on the coaggregation of the two bacteria. Yet, it showed intense antioxidant activity, which was amplified following adherence to bacteria and with the addition of red blood cells or the polycationic peptides. Neem leaf extract, containing polyphenols that adhere to oral surfaces, have the potential to provide long-lasting antibacterial as well as synergic antioxidant activities when in complex with bacteria, red blood cells and lisozyme. Thus, it might be especially effective in periodontal diseases.
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Effect of Coulomb collision on the negative ion extraction mechanism in negative ion sources.
Goto, I; Miyamoto, K; Nishioka, S; Mattei, S; Lettry, J; Abe, S; Hatayama, A
2016-02-01
To improve the H(-) ion beam optics, it is necessary to understand the energy relaxation process of surface produced H(-) ions in the extraction region of Cs seeded H(-) ion sources. Coulomb collisions of charged particles have been introduced to the 2D3V-PIC (two dimension in real space and three dimension in velocity space particle-in-cell) model for the H(-) extraction by using the binary collision model. Due to Coulomb collision, the lower energy part of the ion energy distribution function of H(-) ions has been greatly increased. The mean kinetic energy of the surface produced H(-) ions has been reduced to 0.65 eV from 1.5 eV. It has been suggested that the beam optics of the extracted H(-) ion beam is strongly affected by the energy relaxation process due to Coulomb collision.
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McLucas, E; Moran, M T; Rochev, Y; Carroll, W M; Smith, T J
2006-01-01
The surface properties of vascular devices dictate the initial postimplantation reactions that occur and thus the efficacy of the implantation procedure. Over the last number of years, a number of different stent designs have emerged and stents are generally polished to a mirror finish during the manufacturing procedure. This study sought to investigate the effect of stainless steel surface roughness on endothelial cell gene expression using an appropriate cell culture in vitro assay system. Stainless steel discs were roughened by shot blasting or polished by mechanical polishing. The surface roughness of the treated and untreated discs was determined by atomic force microscopy (AFM). Cells were seeded on collagen type 1 gels and left to attach for 24 h. Stainless steel discs of varying roughness were then placed in contact with the cells and incubated for 24 h. RNA extractions and quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was then performed to determine the expression levels of candidate genes in the treated cells compared to suitable control cells. E-selectin and vascular cellular adhesion molecule (VCAM-1) were found to be significantly up-regulated in cells incubated with polished and roughened samples, indicating endothelial cell activation and inflammation. This study indicates that the surface roughness of stainless steel is an important surface property in the development of vascular stents.
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NASA Astrophysics Data System (ADS)
Beatrici, Anderson; Santos Baptista, Leandra; Mauro Granjeiro, José
2018-03-01
Regenerative Medicine comprises the Biotechnology, Tissue Engineering and Biometrology for stem cell therapy. Starting from stem cells extracted from the patient, autologous implant, these cells are cultured and differentiated into other tissues, for example, articular cartilage. These cells are reorganized into microspheres (cell spheroids). Such tissue units are recombined into functional tissues constructs that can be implanted in the injured region for regeneration. It is necessary the biomechanical characterization of these constructed to determine if their properties are similar to native tissue. In this study was carried out the modeling of the calculation of uncertainty of the surface tension of cellular spheroids with the use of the Young-Laplace equation. We obtained relative uncertainties about 10%.
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Ofusori, David A; Komolafe, Omobola A; Adewole, Olarinde S; Arayombo, Babatunde E; Margolis, Denise; Naicker, Thajasvarie
2016-01-01
To investigate the histological and immunohistochemical effects of aqueous leaf extract of Xylo- pia aethiopica on the pancreas in streptozotocin-induced diabetic rats, 30 adult Wistar rats were divided into three groups (n=10). Group A was the control (administered with equivalent vol- ume of citrate buffer), group B animals were made diabetic by a single intraperitoneal injection of streptozotocin dissolved in citrate buffer (65 mg/kg), group C animals were made diabetic as above and treated with 200mg/kg body weight of aqueous leave extract of Xylopia aethiop- ica for 25 days. Upon animal sacrifice, the pancreas were excised, fixed in 10% formol saline and processed for light microscopy and immunohistochemistry.. The results revealed destruc- tion of the islet cells in the untreated diabetic group as compared with the controls. The extract treated group was characterized by recovery/regenerative processes indicated by improvement in islet morphology. In untreated diabetic rats immunoreactive P-cells were sparse, at variance from the controls. The group treated with aqueous leaf extract of Xylopia aethiopica revealed more intense staining for insulin and significant (p<0.05) increase in the percentage of immuno- labelled surface area when compared with the untreated diabetic group, suggesting the ability of P-cells to secrete insulin in the extract treated rats. We conclude that the aqueous leaf extract of Xylopia aethiopica improves recovery process of P-cells in streptozotocin-induced diabetic rats and might become useful in the management of diabetes related complications.
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Kroh, M; Hendriks, H; Kirby, E G; Sassen, M M
1976-08-01
Development of haploid meiospores of Allomyces arbuscula into germling cells with rhizoids and hyphae was followed during incubation in complete growth medium. The surface structure of encysted meiospores, rhizoids and hyphae before and after extraction of amorphous materials with ethanolic KOH was studied by means of carbon-platinum replicas. After 2--3 min incubation in complete medium 10% of the meiospores were surrounded by a cell wall containing microfibrils embedded in a matrix. Structure of cell walls of encysted meiospores, rhizoids, and hyphae differ from one another by the location of amorphous materials and by the arrangement of chitin microfibrils.
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Morita, Masakazu; Shimamura, Hiroko; Ishida, Natsuko; Imamura, Koreyoshi; Sakiyama, Takaharu; Nakanishi, Kazuhiro
2004-01-01
alpha-Glucosidase was produced using recombinant Aspergillus oryzae by membrane-surface liquid culture (MSLC), a method previously developed by the authors and the results compared with other methods, including shaking flask culture (SFC), agar-plate culture (APC), culture on urethane sponge supports (USC), and liquid surface culture (LSC) to determine possible reasons for the advantageous features of MSLC. When yeast extract was used as a nitrogen source, the amount of enzyme produced by MSLC was 5 or more times higher than those for SFC and LSC, but similar to that using APC. Enzyme production in USC was slightly lower than in MSLC and APC. Cell growth was similar irrespective of the cultivation method used. When NaNO3, a typical inorganic nitrogen source was used, enzyme production in all the cultures was lower than that using yeast extract. However, even using NaNO3, the amount of the enzyme produced by MSLC was 8 to 20 times higher than those by SFC, APC, USC, and LSC. Although cell growth using NaNO3 was similar to that for yeast extract in MSLC, it was markedly decreased in SFC, APC, and LSC. The reason for the difference in enzyme productivity for various cultivation methods using yeast extract and NaNO3 as a nitrogen source is discussed, on the basis of the experimental findings. The role of the oxygen transfer effect and gene expression levels in enzyme production were also examined.
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Dias, Arthur Luiz Baião; Arroio Sergio, Camilla Scarelli; Santos, Philipe; Barbero, Gerardo Fernandéz; Rezende, Camila Alves; Martínez, Julian
2016-07-01
Extracts with bioactive compounds were obtained from the red pepper variety "dedo de moça" (Capsicum baccatum L. var. pendulum) through supercritical fluid extraction with carbon dioxide assisted by ultrasound (SFE-US). The process was tested at pressures of 15, 20 and 25 MPa; temperatures of 40, 50 and 60 °C, and ultrasonic powers of 200, 400 and 600 W applied during 40, 60 and 80 min of extraction. The CO2 mass flow rate was fixed at 1.7569 × 10(-4) kg/s. Global yield, phenolic content, antioxidant capacity and capsaicinoid concentration were evaluated in the extracts. The application of ultrasound raised the global extraction yield of SFE up to 45%. The phenolic content of the extract increased with the application of higher ultrasound power and radiation time. The capsaicinoid yield was also enhanced with ultrasound up to 12%. However, the antioxidant capacity did not increase with the ultrasound application. The BET-based model and the broken and intact cell model fitted well to the kinetic SFE curves. The BET-based model with three adjustable parameters resulted in the best fits to the experimental data. Field emission scanning electron microscopy (FESEM) images showed that SFE disturbed the vegetable matrix, releasing particles from the inner region of the plant cells to their surface. When the ultrasound was applied this effect was more pronounced. On the other hand, cracks, fissures or any sign of rupture were not identified on the sample surface. Copyright © 2016 Elsevier B.V. All rights reserved.
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Cui, Xiao-Xian; Yang, Xiao; Wang, Hui-Jing; Rong, Xing-Yu; Jing, Sha; Xie, You-Hua; Huang, Dan-Feng; Zhao, Chao
2017-01-01
Hepatitis B virus (HBV) infection is endemic in Asia and chronic hepatitis B (CHB) is a major public health issue worldwide. Current treatment strategies for CHB are not satisfactory as they induce a low rate of hepatitis B surface antigen (HBsAg) loss. Extracts were prepared from lettuce hydroponically cultivated in solutions containing glycine or nitrate as nitrogen sources. The lettuce extracts exerted potent anti-HBV effects in HepG2 cell lines in vitro, including significant HBsAg inhibition, HBV replication and transcription inhibition, without exerting cytotoxic effects. When used in combination interferon-alpha 2b (IFNα-2b) or lamivudine (3TC), the lettuce extracts synergistically inhibited HBsAg expression and HBV replication. By using differential metabolomics analysis, Luteolin-7-O-glucoside was identified and confirmed as a functional component of the lettuce extracts and exhibited similar anti-HBV activity as the lettuce extracts in vitro. The inhibition rate on HBsAg was up to 77.4%. Moreover, both the lettuce extracts and luteolin-7-O-glucoside functioned as organic antioxidants and, significantly attenuated HBV-induced intracellular reactive oxygen species (ROS) accumulation. Luteolin-7-O-glucoside also normalized ROS-induced mitochondrial membrane potential damage, which suggests luteolin-7-O-glucoside inhibits HBsAg and HBV replication via a mechanism involving the mitochondria. Our findings suggest luteolin-7-O-glucoside may have potential value for clinical application in CHB and may enhance HBsAg and HBV clearance when used as a combination therapy. PMID:29270164
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Murray, Amber N; Palhano, Fernando L; Bieschke, Jan; Kelly, Jeffery W
2013-01-01
The accumulation of cross-β-sheet amyloid fibrils is the hallmark of amyloid diseases. Recently, we reported the discovery of amyloid disaggregase activities in extracts from mammalian cells and Caenorhabditis elegans. However, we have discovered a problem with the interpretation of our previous results as Aβ disaggregation in vitro. Here, we show that Aβ fibrils adsorb to the plastic surface of multiwell plates and Eppendorf tubes. This adsorption is markedly increased in the presence of complex biological mixtures subjected to a denaturing air-water interface. The time-dependent loss of thioflavin T fluorescence that we interpreted previously as disaggregation is due to increased adsorption of Aβ amyloid to the surfaces of multiwell plates and Eppendorf tubes in the presence of biological extracts. As the proteins in biological extracts denature over time at the air-water interface due to agitation/shaking, their adsorption increases, in turn promoting adsorption of amyloid fibrils. We delineate important control experiments that quantify the extent of amyloid adsorption to the surface of plastic and quartz containers. Based on the results described in this article, we conclude that our interpretation of the kinetic fibril disaggregation assay data previously reported in Bieschke et al., Protein Sci 2009;18:2231–2241 and Murray et al., Protein Sci 2010;19:836–846 is invalid when used as evidence for a disaggregase activity. Thus, we correct the two prior publications reporting that worm or mammalian cell extracts disaggregate Aβ amyloid fibrils in vitro at 37°C (see Corrigenda in this issue of Protein Science). We apologize for misinterpreting our previous data and for any confounding experimental efforts this may have caused. PMID:23963844
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Murray, Amber N; Palhano, Fernando L; Bieschke, Jan; Kelly, Jeffery W
2013-11-01
The accumulation of cross-β-sheet amyloid fibrils is the hallmark of amyloid diseases. Recently, we reported the discovery of amyloid disaggregase activities in extracts from mammalian cells and Caenorhabditis elegans. However, we have discovered a problem with the interpretation of our previous results as Aβ disaggregation in vitro. Here, we show that Aβ fibrils adsorb to the plastic surface of multiwell plates and Eppendorf tubes. This adsorption is markedly increased in the presence of complex biological mixtures subjected to a denaturing air-water interface. The time-dependent loss of thioflavin T fluorescence that we interpreted previously as disaggregation is due to increased adsorption of Aβ amyloid to the surfaces of multiwell plates and Eppendorf tubes in the presence of biological extracts. As the proteins in biological extracts denature over time at the air-water interface due to agitation/shaking, their adsorption increases, in turn promoting adsorption of amyloid fibrils. We delineate important control experiments that quantify the extent of amyloid adsorption to the surface of plastic and quartz containers. Based on the results described in this article, we conclude that our interpretation of the kinetic fibril disaggregation assay data previously reported in Bieschke et al., Protein Sci 2009;18:2231-2241 and Murray et al., Protein Sci 2010;19:836-846 is invalid when used as evidence for a disaggregase activity. Thus, we correct the two prior publications reporting that worm or mammalian cell extracts disaggregate Aβ amyloid fibrils in vitro at 37°C (see Corrigenda in this issue of Protein Science). We apologize for misinterpreting our previous data and for any confounding experimental efforts this may have caused. © 2013 The Protein Society.
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Wang, Jian; Evangelou, Bill P.; Nielsen, Mark T.
1992-01-01
Surface chemical characteristics of root cell walls extracted from two tobacco genotypes exhibiting differential tolerance to Mn toxicity were studied using potentiometric pH titration and Fourier transform infrared spectroscopy. The Mn-sensitive genotype KY 14 showed a stronger interaction of its cell wall surface with metal ions than did the Mn-tolerant genotype Tobacco Introduction (T.I.) 1112. This observation may be attributed to the relatively higher ratio of COO− to COOH in KY 14 cell walls than that found in the cell walls of T.I. 1112 in the pH range of 4 to 10. For both genotypes, the strength of binding between metal ions and cell wall surface was in the order of Cu > Ca > Mn > Mg > Na. However, a slightly higher preference of Ca over Mn was observed with the T.I. 1112 cell wall. This may explain the high accumulation of Mn in the leaves of Mn-tolerant genotype T.I. 1112 rather than the high accumulation of Mn in roots, as occurred in Mn-sensitive KY 14. It is concluded that surface chemical characteristics of cell walls may play an important role in plant metal ion uptake and tolerance. PMID:16652989
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NASA Astrophysics Data System (ADS)
Smeekens, Johanna M.; Chen, Weixuan; Wu, Ronghu
2015-04-01
Cell surface N-glycoproteins play extraordinarily important roles in cell-cell communication, cell-matrix interactions, and cellular response to environmental cues. Global analysis is exceptionally challenging because many N-glycoproteins are present at low abundances and effective separation is difficult to achieve. Here, we have developed a novel strategy integrating metabolic labeling, copper-free click chemistry, and mass spectrometry (MS)-based proteomics methods to analyze cell surface N-glycoproteins comprehensively and site-specifically. A sugar analog containing an azido group, N-azidoacetylgalactosamine, was fed to cells to label glycoproteins. Glycoproteins with the functional group on the cell surface were then bound to dibenzocyclooctyne-sulfo-biotin via copper-free click chemistry under physiological conditions. After protein extraction and digestion, glycopeptides with the biotin tag were enriched by NeutrAvidin conjugated beads. Enriched glycopeptides were deglycosylated with peptide- N-glycosidase F in heavy-oxygen water, and in the process of glycan removal, asparagine was converted to aspartic acid and tagged with 18O for MS analysis. With this strategy, 144 unique N-glycopeptides containing 152 N-glycosylation sites were identified in 110 proteins in HEK293T cells. As expected, 95% of identified glycoproteins were membrane proteins, which were highly enriched. Many sites were located on important receptors, transporters, and cluster of differentiation proteins. The experimental results demonstrated that the current method is very effective for the comprehensive and site-specific identification of the cell surface N-glycoproteome and can be extensively applied to other cell surface protein studies.
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Silicon Dioxide Thin Film Mediated Single Cell Nucleic Acid Isolation
Bogdanov, Evgeny; Dominova, Irina; Shusharina, Natalia; Botman, Stepan; Kasymov, Vitaliy; Patrushev, Maksim
2013-01-01
A limited amount of DNA extracted from single cells, and the development of single cell diagnostics make it necessary to create a new highly effective method for the single cells nucleic acids isolation. In this paper, we propose the DNA isolation method from biomaterials with limited DNA quantity in sample, and from samples with degradable DNA based on the use of solid-phase adsorbent silicon dioxide nanofilm deposited on the inner surface of PCR tube. PMID:23874571
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Rebamipide increases the mucin-like glycoprotein production in corneal epithelial cells.
Takeji, Yasuhiro; Urashima, Hiroki; Aoki, Akihiro; Shinohara, Hisashi
2012-06-01
Dry eye is a multifactorial disease of tears and the ocular surface due to tear deficiency or excessive tear evaporation. Tear film instability is due to a disturbance in ocular surface mucin leading to a dysfunction of mucin, resulting in dry eye. In this study, we examined the effect of rebamipide, an anti-ulcer agent, on glycoconjugate production, as an indicator of mucin-like glycoprotein in cultured corneal epithelial cells. Further, we investigated the effect of rebamipide on the gene expression of membrane-associated mucins. Confluent cultured human corneal epithelial cells were incubated with rebamipide for 24 h. The glycoconjugate content in the supernatant and the cell extracts was measured by wheat germ agglutinin-enzyme-linked lectin assay combined gel-filtration method. In the experiment on mucin gene expression, cultured human corneal epithelial cells were collected at 0, 3, 6, and 12 h after administration of rebamipide. Real-time quantitative polymerase chain reaction was used to analyze the quantity of MUC1, MUC 4, and MUC16 gene expression. Rebamipide significantly increased the glycoconjugate contents in the supernatant and cell extract. In the mucin gene expression in the cells, rebamipide increased MUC1 and MUC4 gene expression, but did not increase MUC16 gene expression. Rebamipide promoted glycoconjugate, which has a property as a mucin-like glycoprotein, in human corneal epithelial cells. The increased production was mediated by MUC1 and MUC4 gene expression.
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Madeira, Petrus L. B.; Carvalho, Letícia T.; Paschoal, Marco A. B.; de Sousa, Eduardo M.; Moffa, Eduardo B.; da Silva, Marcos A. dos Santos; Tavarez, Rudys de Jesus Rodolfo; Gonçalves, Letícia M.
2016-01-01
The purpose of this study was to investigate whether immersion of a denture surface in lemongrass extract (LGE) has effects on C. albicans biofilms, human cell viability and denture surface. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were performed for LGE against C. albicans. For biofilm analysis, discs were fabricated using a denture acrylic resin with surface roughness standardization. C. albicans biofilms were developed on saliva-coated discs, and the effects of LGE at MIC, 5XMIC, and 10XMIC were investigated during biofilm formation and after biofilm maturation. Biofilms were investigated for cell counting, metabolic activity, and microscopic analysis. The cytotoxicity of different concentrations of LGE to peripheral blood mononuclear cells (PBMC) was analyzed using MTT. The effects of LGE on acrylic resin were verified by measuring changes in roughness, color and flexural strength after 28 days of immersion. Data were analyzed by ANOVA, followed by a Tukey test at a 5% significance level. The minimal concentration of LGE required to inhibit C. albicans growth was 0.625 mg/mL, while MFC was 2.5 mg/mL. The presence of LGE during biofilm development resulted in a reduction of cell counting (p < 0.05), which made the MIC sufficient to reduce approximately 90% of cells (p < 0.0001). The exposure of LGE after biofilm maturation also had a significant antifungal effect at all concentrations (p < 0.05). When compared to the control group, the exposure of PBMC to LGE at MIC resulted in similar viability (p > 0.05). There were no verified differences in color perception, roughness, or flexural strength after immersion in LGE at MIC compared to the control (p > 0.05). It could be concluded that immersion of the denture surface in LGE was effective in reducing C. albicans biofilms with no deleterious effects on acrylic properties at MIC. MIC was also an effective and safe concentration for use. PMID:27446818
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Madeira, Petrus L B; Carvalho, Letícia T; Paschoal, Marco A B; de Sousa, Eduardo M; Moffa, Eduardo B; da Silva, Marcos A Dos Santos; Tavarez, Rudys de Jesus Rodolfo; Gonçalves, Letícia M
2016-01-01
The purpose of this study was to investigate whether immersion of a denture surface in lemongrass extract (LGE) has effects on C. albicans biofilms, human cell viability and denture surface. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were performed for LGE against C. albicans. For biofilm analysis, discs were fabricated using a denture acrylic resin with surface roughness standardization. C. albicans biofilms were developed on saliva-coated discs, and the effects of LGE at MIC, 5XMIC, and 10XMIC were investigated during biofilm formation and after biofilm maturation. Biofilms were investigated for cell counting, metabolic activity, and microscopic analysis. The cytotoxicity of different concentrations of LGE to peripheral blood mononuclear cells (PBMC) was analyzed using MTT. The effects of LGE on acrylic resin were verified by measuring changes in roughness, color and flexural strength after 28 days of immersion. Data were analyzed by ANOVA, followed by a Tukey test at a 5% significance level. The minimal concentration of LGE required to inhibit C. albicans growth was 0.625 mg/mL, while MFC was 2.5 mg/mL. The presence of LGE during biofilm development resulted in a reduction of cell counting (p < 0.05), which made the MIC sufficient to reduce approximately 90% of cells (p < 0.0001). The exposure of LGE after biofilm maturation also had a significant antifungal effect at all concentrations (p < 0.05). When compared to the control group, the exposure of PBMC to LGE at MIC resulted in similar viability (p > 0.05). There were no verified differences in color perception, roughness, or flexural strength after immersion in LGE at MIC compared to the control (p > 0.05). It could be concluded that immersion of the denture surface in LGE was effective in reducing C. albicans biofilms with no deleterious effects on acrylic properties at MIC. MIC was also an effective and safe concentration for use.
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Antifertility effects of methanolic pod extract of Albizzia lebbeck (L.) Benth in male rats.
Gupta, R S; Kachhawa, J B S; Chaudhary, R
2004-06-01
To evaluate the antifertility activity of the methanolic pod extract of Albizzia lebbeck (L.) Benth in male albino rats. The methanolic pod extract of Albizzia lebbeck was administrated orally for 60 days at 50, 100 and 200 mg.kg(-1).day(-1) to male albino rats. Sperm motility and density in cauda epididymides were assessed. Biochemical and histological analysis were performed in blood samples and reproductive organs. Albizzia lebbeck pod extract brought about a significant decrease in the weights of testis, seminal vesicles, epdidymis and ventral prostate. The sperm motility and density were significantly reduced. There was a marked reduction in the numbers of primary spermatocytes, secondary spermatocytes and spermatids. The Sertoli cell count as well as its cross sectional surface area were significantly decreased. The Leydig cell nuclear area and the number of mature Leydig cells were also significantly decreased. The protein, glycogen and cholesterol content of the testis, the fructose in the seminal vesicles and protein in the epididymis were significantly decreased. The RBC and WBC counts, haemoglobin, haematocrit and blood sugar were within the normal range. The methanolic extract of A. lebbeck pods causes spermatogenic arrest in male albino rats.
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Tomaz, Ivana; Maslov, Luna; Stupić, Domagoj; Preiner, Darko; Ašperger, Danijela; Karoglan Kontić, Jasminka
2016-01-01
For the characterisation of grape cultivars, the profile and content of flavonoids are important because these compounds impact grape and wine quality. To determine the correct profile and content of flavonoids, the use of robust, sensitive and reliable methods is necessary. The object of this research is to develop a new ultrasound-assisted extraction (UAE) method for the recovery of flavonoids from grape skins using response surface methodology. Optimisation of UAE was performed using a complementary study combining a Box-Behnken experimental design with qualitative analysis by high-performance liquid chromatography. Optimal extraction conditions were obtained using the extraction solvent composed of acetonitrile:water:formic acid (26:73:1, v/v/v) at an extraction temperature of 50 °C, an extraction time of 15 min in a single-extraction step and with a solid-to-solvent ratio of 1:80 g/mL. The calculated relative standard deviations for the optimal extraction method were very low, measuring less than 5%. This study demonstrates that numerous factors have strong effects on the extraction efficiency, including the type of organic modifier and its percentage in the extraction solvent, the number of extraction steps, the solid-to-solvent ratio, the extraction time and temperature and, finally, the particular nature of analyte and their position within the grape skin cell. Copyright © 2015 John Wiley & Sons, Ltd.
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Effect of flagella expression on adhesion of Achromobacter piechaudii to chalk surfaces.
Nejidat, A; Saadi, I; Ronen, Z
2008-12-01
To examine flagella role and cell motility in adhesion of Achromobacter piechaudii to chalk. Transmission electron microscopy revealed that stationary cells have thicker and longer flagella than logarithmic cells. SDS-PAGE analysis showed that flagellin was more abundant in stationary cells than logarithmic ones. Sonication or inhibition of flagellin synthesis caused a 30% reduction in adhesion to chalk. Preincubation of chalk with flagella extracts reduced adhesion, by 50%. Three motility mutants were isolated. Mutants 94 and 153 were nonmotile, expressed normal levels of flagellin, have regular flagella and exhibited reduced adhesion. Mutant 208 expressed low levels of flagellin, no flagella and a spherical cell shape but with normal adhesion capacity. Multiple cell surface factors affect the adhesion efficiency to chalk. Flagella per se through physical interaction and through cell motility contribute to the adhesion process. The adhesion behaviour of mutant 208 suggests that cell shape can compensate for flagellar removal and motility. Physiological status affects bacterial cell surface properties and hence adhesion efficiency to chalk. This interaction is essential to sustain biodegradation activities and thus, remediation of contaminated chalk aquifers.
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Toxicity assessment of carbon black waste: A by-product from oil refineries.
Zhen, Xu; Ng, Wei Cheng; Fendy; Tong, Yen Wah; Dai, Yanjun; Neoh, Koon Gee; Wang, Chi-Hwa
2017-01-05
In Singapore, approximately 30t/day of carbon-based solid waste are produced from petrochemical processes. This carbon black waste has been shown to possess physical properties that are characteristic of a good adsorbent such as high external surface area. Therefore, there is a growing interest to reutilize and process this carbon black waste into secondary materials such as adsorbents. However, the carbon black waste obtained from petrochemical industries may contain heavy metals that are hazardous to human health and the environment, hence restricting its full potential for re-utilization. Therefore, it is important to examine the possible toxicity effects and toxicity mechanism of carbon black waste on human health. In this study, inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis showed that the heavy metals, vanadium (V), molybdenum (Mo) and nickel (Ni), were present in the carbon black waste in high concentrations. Three human cell lines (HepG2 cells, MRC-5 cells and MDA-MB-231 cells) were used to investigate the toxicity of carbon black waste extract in a variety of in vitro assays. Results from MTS assays indicated that carbon black waste extract decreased the viability of all three cell lines in a dose and time-dependent manner. Observations from confocal microscopy further confirmed this phenomenon. Flow cytometry assay also showed that carbon black waste extract induced apoptosis of human cell lines, and the level of apoptosis increased with increasing waste concentration. Results from reactive oxygen species (ROS) assay indicated that carbon black waste extract induced oxidative stress by increasing intracellular ROS generation in these three human cell lines. Moreover, induction of oxidative damage in these cells was also observed through the alteration of glutathione (GSH) and superoxide dismutase (SOD) activities. Last but not least, by treating the cells with V-spiked solution of concentration equivalent to that found in the carbon black waste extract, V was identified as the main culprit for the high toxicity of carbon black waste extract. These findings could potentially provide insight into the hazards of carbon black waste extract and its toxicity mechanism on human cell lines. Copyright © 2016 Elsevier B.V. All rights reserved.
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Multiscale Model of Swarming Bacteria
NASA Astrophysics Data System (ADS)
Alber, Mark
2011-03-01
Many bacteria can rapidly traverse surfaces from which they are extracting nutrient for growth. They generate flat, spreading colonies, called swarms because they resemble swarms of insects. In the beginning of the talk, swarms of the M. xanthus will be described in detail. Individual M. xanthus cells are elongated; they always move in the direction of their long axis; and they are in constant motion, repeatedly touching each other. As a cell glides, the slime capsule of a cell interacts with the bare agar surface, non-oriented slime which arises from the surface contact with the slime capsule, or oriented slime trails. Remarkably, cells regularly reverse their gliding directions. In this talk a detailed cell- and behavior-based computational model of M. xanthus swarming will be used to demonstrate that reversals of gliding direction and cell bending are essential for swarming and that specific reversal frequencies result in optimal swarming rate of the whole population. This suggests that the circuit regulating reversals evolved to its current sensitivity under selection for growth achieved by swarming.
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Nguyen, Hoang-Yen T; Vo, Bach-Hue T; Nguyen, Lac-Thuy H; Bernad, Jose; Alaeddine, Mohamad; Coste, Agnes; Reybier, Karine; Pipy, Bernard; Nepveu, Françoise
2013-08-26
Crinum latifolium L. (CL) leaf extracts have been traditionally used in Vietnam and are now used all over the world for the treatment of prostate cancer. However, the precise cellular mechanisms of the action of CL extracts remain unclear. To examine the effects of CL samples on the anti-tumour activity of peritoneal murine macrophages. The properties of three extracts (aqueous, flavonoid, alkaloid), one fraction (alkaloid), and one pure compound (6-hydroxycrinamidine) obtained from CL, were studied (i) for redox capacities (DPPH and bleaching beta-carotene assays), (ii) on murine peritoneal macrophages (MTT assay) and on lymphoma EL4-luc2 cells (luciferine assay) for cytotoxicity, (iii) on macrophage polarization (production of ROS and gene expression by PCR), and (iv) on the tumoricidal functions of murine peritoneal macrophages (lymphoma cytotoxicity by co-culture with syngeneic macrophages). The total flavonoid extract with a high antioxidant activity (IC50=107.36 mg/L, DPPH assay) showed an inhibitory action on cancer cells. Alkaloid extracts inhibited the proliferation of lymphoma cells either by directly acting on tumour cells or by activating of the tumoricidal functions of syngeneic macrophages. The aqueous extract induced mRNA expression of tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin 6 (IL-6) indicating differentiation of macrophages into pro-inflammatory M1 polarized macrophages. The total flavonoid, alkaloid extracts and an alkaloid fraction induced the expression of the formyl peptide receptor (FPR) on the surface of the polarized macrophages that could lead to the activation of macrophages towards the M1 phenotype. Aqueous and flavonoid extracts enhanced NADPH quinine oxido-reductase 1 (NQO1) mRNA expression in polarized macrophages which could play an important role in cancer chemoprevention. All the samples studied were non-toxic to normal living cells and the pure alkaloid tested, 6-hydroxycrinamidine, was not active in any of the models investigated. Our results indicate that CL extracts and alkaloid fraction (but not pure 6-hydroxycrinamidine) inhibit the proliferation of lymphoma cells in multiple pathways. Our results are in accordance with traditional usage and encourage further studies and in vivo assays. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
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Park, Jong Hwan; Jung, Youngsuk; Yang, Yooseong; Shin, Hyun Suk; Kwon, Soonchul
2016-10-05
For efficient solar cells based on organic semiconductors, a good mixture of photoactive materials in the bulk heterojunction on the length scale of several tens of nanometers is an important requirement to prevent exciton recombination. Herein, we demonstrate that nanoporous titanium dioxide inverse opal structures fabricated using a self-assembled monolayer method and with enhanced infiltration of electron-donating polymers is an efficient electron-extracting layer, which enhances the photovoltaic performance. A calcination process generates an inverse opal structure of titanium dioxide (<70 nm of pore diameters) providing three-dimensional (3D) electron transport pathways. Hole-transporting polymers was successfully infiltrated into the pores of the surface-modified titanium dioxide under vacuum conditions at 200 °C. The resulting geometry expands the interfacial area between hole- and electron-transport materials, increasing the thickness of the active layer. The controlled polymer-coating process over titanium dioxide materials enhanced photocurrent of the solar cell device. Density functional theory calculations show improved interfacial adhesion between the self-assembled monolayer-modified surface and polymer molecules, supporting the experimental result of enhanced polymer infiltration into the voids. These results suggest that the 3D inverse opal structure of the surface-modified titanium dioxide can serve as a favorable electron-extracting layer in further enhancing optoelectronic performance based on organic or organic-inorganic hybrid solar cell.
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Arabidopsis thalianafrom Polarization Transfer Solid-State NMR
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, Paul B; Wang, Tuo; Park, Yong Bum
2014-07-23
Polysaccharide-rich plant cell walls are hydrated under functional conditions, but the molecular interactions between water and polysaccharides in the wall have not been investigated. In this work, we employ polarization transfer solid-state NMR techniques to study the hydration of primary-wall polysaccharides of the model plant, Arabidopsis thaliana. By transferring water 1H polarization to polysaccharides through distance- and mobility-dependent 1H–1H dipolar couplings and detecting it through polysaccharide 13C signals, we obtain information about water proximity to cellulose, hemicellulose, and pectins as well as water mobility. Both intact and partially extracted cell wall samples are studied. Our results show that water–pectin polarizationmore » transfer is much faster than water–cellulose polarization transfer in all samples, but the extent of extraction has a profound impact on the water–polysaccharide spin diffusion. Removal of calcium ions and the consequent extraction of homogalacturonan (HG) significantly slowed down spin diffusion, while further extraction of matrix polysaccharides restored the spin diffusion rate. These trends are observed in cell walls with similar water content, thus they reflect inherent differences in the mobility and spatial distribution of water. Combined with quantitative analysis of the polysaccharide contents, our results indicate that calcium ions and HG gelation increase the amount of bound water, which facilitates spin diffusion, while calcium removal disrupts the gel and gives rise to highly dynamic water, which slows down spin diffusion. The recovery of spin diffusion rates after more extensive extraction is attributed to increased water-exposed surface areas of the polysaccharides. Water–pectin spin diffusion precedes water–cellulose spin diffusion, lending support to the single-network model of plant primary walls in which a substantial fraction of the cellulose surface is surrounded by pectins.« less
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Optimizing pressurized liquid extraction of microbial lipids using the response surface method.
Cescut, J; Severac, E; Molina-Jouve, C; Uribelarrea, J-L
2011-01-21
Response surface methodology (RSM) was used for the determination of optimum extraction parameters to reach maximum lipid extraction yield with yeast. Total lipids were extracted from oleaginous yeast (Rhodotorula glutinis) using pressurized liquid extraction (PLE). The effects of extraction parameters on lipid extraction yield were studied by employing a second-order central composite design. The optimal condition was obtained as three cycles of 15 min at 100°C with a ratio of 144 g of hydromatrix per 100 g of dry cell weight. Different analysis methods were used to compare the optimized PLE method with two conventional methods (Soxhlet and modification of Bligh and Dyer methods) under efficiency, selectivity and reproducibility criteria thanks to gravimetric analysis, GC with flame ionization detector, High Performance Liquid Chromatography linked to Evaporative Light Scattering Detector (HPLC-ELSD) and thin-layer chromatographic analysis. For each sample, the lipid extraction yield with optimized PLE was higher than those obtained with referenced methods (Soxhlet and Bligh and Dyer methods with, respectively, a recovery of 78% and 85% compared to PLE method). Moreover, the use of PLE led to major advantages such as an analysis time reduction by a factor of 10 and solvent quantity reduction by 70%, compared with traditional extraction methods. Copyright © 2010 Elsevier B.V. All rights reserved.
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Baynham, Patricia J; Ramsey, Deborah M; Gvozdyev, Borys V; Cordonnier, Ellen M; Wozniak, Daniel J
2006-01-01
Pseudomonas aeruginosa is an opportunistic pathogen that is commonly found in water and soil. In order to colonize surfaces with low water content, P. aeruginosa utilizes a flagellum-independent form of locomotion called twitching motility, which is dependent upon the extension and retraction of type IV pili. This study demonstrates that AlgZ, previously identified as a DNA-binding protein absolutely required for transcription of the alginate biosynthetic operon, is required for twitching motility. AlgZ may be required for the biogenesis or function of type IV pili in twitching motility. Transmission electron microscopy analysis of an algZ deletion in nonmucoid PAO1 failed to detect surface pili. To examine expression and localization of PilA (the major pilin subunit), whole-cell extracts and cell surface pilin preparations were analyzed by Western blotting. While the PilA levels present in whole-cell extracts were similar for wild-type P. aeruginosa and P. aeruginosa with the algZ deletion, the amount of PilA on the surface of the cells was drastically reduced in the algZ mutant. Analysis of algZ and algD mutants indicates that the DNA-binding activity of AlgZ is essential for the regulation of twitching motility and that this is independent of the role of AlgZ in alginate expression. These data show that AlgZ DNA-binding activity is required for twitching motility independently of its role in alginate production and that this involves the surface localization of type IV pili. Given this new role in twitching motility, we propose that algZ (PA3385) be designated amrZ (alginate and motility regulator Z).
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Electron beam extraction on plasma cathode electron sources system
NASA Astrophysics Data System (ADS)
Purwadi, Agus; Taufik, M., Lely Susita R.; Suprapto, Saefurrochman, H., Anjar A.; Wibowo, Kurnia; Aziz, Ihwanul; Siswanto, Bambang
2017-03-01
ELECTRON BEAM EXTRACTION ON PLASMA CATHODE ELECTRON SOURCES SYSTEM. The electron beam extraction through window of Plasma Generator Chamber (PGC) for Pulsed Electron Irradiator (PEI) device and simulation of plasma potential has been studied. Plasma electron beam is extracted to acceleration region for enlarging their power by the external accelerating high voltage (Vext) and then it is passed foil window of the PEI for being irradiated to any target (atmospheric pressure). Electron beam extraction from plasma surface must be able to overcome potential barrier at the extraction window region which is shown by estimate simulation (Opera program) based on data of plasma surface potential of 150 V with Ueks values are varied by 150 kV, 175 kV and 200 kV respectively. PGC is made of 304 stainless steel with cylindrical shape in 30 cm of diameter, 90 cm length, electrons extraction window as many as 975 holes on the area of (15 × 65) cm2 with extraction hole cell in 0.3 mm of radius each other, an cylindrical shape IEP chamber is made of 304 stainless steel in 70 cm diameter and 30 cm length. The research result shown that the acquisition of electron beam extraction current depends on plasma parameters (electron density ne, temperature Te), accelerating high voltage Vext, the value of discharge parameter G, anode area Sa, electron extraction window area Se and extraction efficiency value α.
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Extraction of Polysaccharide from Spirulina and Evaluation of Its Activities.
Wang, Bingyue; Liu, Qian; Huang, Yinghong; Yuan, Yueling; Ma, Qianqian; Du, Manling; Cai, Tiange; Cai, Yu
2018-01-01
Polysaccharide of Spirulina platensis (PSP) is a kind of water-soluble polysaccharide extracted from Spirulina platensis . It has been proved to have antitumor, antioxidation, antiaging, and antivirus properties. And it has a promising prospect for wide application. This study aims to identify an extraction process for high-purity polysaccharide in Spirulina (PSP) through a series of optimization methods and then evaluates its initial antiaging activities. Four kinds of extraction methods-hot-water extraction, alkali extraction, ultrasonic-assisted extraction, and freeze-thaw extraction-were compared to find the optimal one, which was further optimized by response surface methodology. PSP was obtained after the crude PSP was deproteinized and depigmented. The antiaging effects of PSP were preliminarily evaluated through in vitro cell experiments. The alkali extraction method was determined as the optimal method, with the optimized extraction process consisting of a solid-liquid ratio of 1 : 50, a pH value of 10.25, a temperature of 89.24°C, and a time of 9.99 h. The final PSP contained 71.65% of polysaccharide and 8.54% of protein. At a concentration of 50 μ g/mL, PSP exerted a significant promoting effect on the proliferation and traumatic fusion of human immortalized epidermal cells HaCaT. An extraction method for high-purity PSP with a high extraction rate was established, and in vitro results suggest antioxidation and antiaging activities.
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NASA Astrophysics Data System (ADS)
Carlson, H. K.; Iavarone, A. T.; Gorur, A.; Yeo, B. S.; Tran, R.; Melnyk, R. A.; Mathies, R. A.; Auer, M.; Coates, J. D.
2011-12-01
Almost nothing is known about the mechanisms of dissimilatory metal reduction by Gram-positive bacteria, although they have been shown to be the dominant species in some environments. Thermincola potens strain JR was isolated from the anode of a microbial fuel cell inoculated with anaerobic digester sludge and operated at 55 °C. Preliminary characterization revealed that T. potens coupled acetate oxidation to the reduction of hydrous ferric oxides (HFO) or the humic substances analog, anthraquinone-2,6-disulfonate (AQDS). The genome of T. potens was recently sequenced, and the abundance of multiheme c-type cytochromes (MHCs) is unusual for a Gram-positive bacterium. We present evidence from trypsin shaving LC-MS/MS experiments and surface-enhanced Raman spectroscopy (SERS) that indicates the expression of a number of MHCs during T. potens growth on either HFO or AQDS and that several MHCs are localized to the cell wall or cell surface of T. potens. Furthermore, one of the MHCs can be extracted from cells with low pH or denaturants suggesting a loose association with the cell wall or cell surface. Electron microscopy does not reveal an S-layer, and the precipitation of silver metal on the cell surface is inhibited by cyanide, supporting the involvement of surface-localized redox-active heme proteins in dissimilatory metal reduction. These results are the first direct evidence for cell-wall associated cytochromes and MHC involvement in conducting electrons across the cell envelope of a Gram-positive bacterium.
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Tang, Wei; Li, Chao; He, Zengguo; Pan, Fen; Pan, Shuo; Wang, Yanping
2017-11-20
Lactobacillus plantarum MA2 was isolated from traditional Chinese Tibetan kefir grains. Its antioxidant properties had been demonstrated in vitro and in vivo previously. In the present study, the probiotic characteristics of this strain were further evaluated by investigating its acid and bile salt tolerances, cell surface hydrophobicity, and autoaggregation, respectively. In addition, the cellular antioxidant activity (CAA) assay was applied to test the antioxidant capacity of the isolate in different growth phases. Same method was also used to evaluate the antioxidant capacity of its fermentation supernatant, cell-free extract, and intact cell quantitatively. The results of probiotic characteristic tests showed that MA2 could survive at pH 2.5 and 0.3% bile salt. Meanwhile, the measurements of cell surface hydrophobicity and autoaggregation were 45.29 ± 2.15 and 6.30 ± 0.34%, respectively. The results of cellular antioxidant activity tests indicated that MA2 had high antioxidant potential. The CAA value of logarithmic phase cell-free extract of MA2 (39,450.00 ± 424.05 μmol quercetin equivalents/100 g sample) was significantly higher than that in stationary phase cell-free extract (3395.98 ± 126.06 μmol quercetin equivalents/100 g sample) and that of fermentation supernatant in logarithmic phase (2174.41 ± 224.47 μmol quercetin equivalents/100 g sample) (p < 0.05). The CAA method was successively applied to evaluate the antioxidant capacity of MA2 in this study, which suggests that it could be used as a useful method for lactic acid bacteria antioxidant potential evaluation.
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Magnetic field design for selecting and aligning immunomagnetic labeled cells.
Tibbe, Arjan G J; de Grooth, Bart G; Greve, Jan; Dolan, Gerald J; Rao, Chandra; Terstappen, Leon W M M
2002-03-01
Recently we introduced the CellTracks cell analysis system, in which samples are prepared based on a combination of immunomagnetic selection, separation, and alignment of cells along ferromagnetic lines. Here we describe the underlying magnetic principles and considerations made in the magnetic field design to achieve the best possible cell selection and alignment of magnetically labeled cells. Materials and Methods Computer simulations, in combination with experimental data, were used to optimize the design of the magnets and Ni lines to obtain the optimal magnetic configuration. A homogeneous cell distribution on the upper surface of the sample chamber was obtained with a magnet where the pole faces were tilted towards each other. The spatial distribution of magnetically aligned objects in between the Ni lines was dependent on the ratio of the diameter of the aligned object and the line spacing, which was tested with magnetically and fluorescently labeled 6 microm polystyrene beads. The best result was obtained when the line spacing was equal to or smaller than the diameter of the aligned object. The magnetic gradient of the designed permanent magnet extracts magnetically labeled cells from any cell suspension to a desired plane, providing a homogeneous cell distribution. In addition, it magnetizes ferro-magnetic Ni lines in this plane whose additional local gradient adds to the gradient of the permanent magnet. The resultant gradient aligns the magnetically labeled cells first brought to this plane. This combination makes it possible, in a single step, to extract and align cells on a surface from any cell suspension. Copyright 2002 Wiley-Liss, Inc.
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Kearney, Sinéad M.; Kilcawley, Niamh A.; Early, Philip L.; Glynn, Macdara T.; Ducrée, Jens
2016-01-01
Here we present retrieval of Peripheral Blood Mononuclear Cells by density-gradient medium based centrifugation for subsequent analysis of the leukocytes on an integrated microfluidic “Lab-on-a-Disc” cartridge. Isolation of white blood cells constitutes a critical sample preparation step for many bioassays. Centrifugo-pneumatic siphon valves are particularly suited for blood processing as they function without need of surface treatment and are ‘low-pass’, i.e., holding at high centrifugation speeds and opening upon reduction of the spin rate. Both ‘hydrostatically’ and ‘hydrodynamically’ triggered centrifugo-pneumatic siphon valving schemes are presented. Firstly, the geometry of the pneumatic chamber of hydrostatically primed centrifugo-pneumatic siphon valves is optimised to enable smooth and uniform layering of blood on top of the density-gradient medium; this feature proves to be key for efficient Peripheral Blood Mononuclear Cell extraction. A theoretical analysis of hydrostatically primed valves is also presented which determines the optimum priming pressure for the individual valves. Next, ‘dual siphon’ configurations for both hydrostatically and hydrodynamically primed centrifugo-pneumatic siphon valves are introduced; here plasma and Peripheral Blood Mononuclear Cells are extracted through a distinct siphon valve. This work represents a first step towards enabling on disc multi-parameter analysis. Finally, the efficiency of Peripheral Blood Mononuclear Cells extraction in these structures is characterised using a simplified design. A microfluidic mechanism, which we termed phase switching, is identified which affects the efficiency of Peripheral Blood Mononuclear Cell extraction. PMID:27167376
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Stirbat, Tomita Vasilica; Mgharbel, Abbas; Bodennec, Selena; Ferri, Karine; Mertani, Hichem C.; Rieu, Jean-Paul; Delanoë-Ayari, Hélène
2013-01-01
What governs tissue organization and movement? If molecular and genetic approaches are able to give some answers on these issues, more and more works are now giving a real importance to mechanics as a key component eventually triggering further signaling events. We chose embryonic cell aggregates as model systems for tissue organization and movement in order to investigate the origin of some mechanical constraints arising from cells organization. Steinberg et al. proposed a long time ago an analogy between liquids and tissues and showed that indeed tissues possess a measurable tissue surface tension and viscosity. We question here the molecular origin of these parameters and give a quantitative measurement of adhesion versus contractility in the framework of the differential interfacial tension hypothesis. Accompanying surface tension measurements by angle measurements (at vertexes of cell-cell contacts) at the cell/medium interface, we are able to extract the full parameters of this model: cortical tensions and adhesion energy. We show that a tunable surface tension and viscosity can be achieved easily through the control of cell-cell contractility compared to cell-medium one. Moreover we show that -catenin is crucial for this regulation to occur: these molecules appear as a catalyser for the remodeling of the actin cytoskeleton underneath cell-cell contact, enabling a differential contractility between the cell-medium and cell-cell interface to take place. PMID:23390488
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Qi, Feng-jie; Zhang, Xiu-wei; Zhang, Yong-xing; Dai, Shun-dong; Wang, En-hua
2006-05-01
To study the clonality of polygonal cells and surface cuboidal cells in the so-called pulmonary sclerosing hemangioma (PSH). 17 female surgically resected PSH were found. The polygonal cells and surface cuboidal cells of the 17 PSH cases were microdissected from routine hematoxylin and eosin-stained sections. Genomic DNA was extracted, pretreated through incubation with methylation-sensitive restrictive endonuclease HhaI or HpaII, and amplified by nested polymerase chain reaction for X chromosome-linked androgen receptor (AR) and phosphoglycerate kinase (PGK) genes. The length polymorphism of AR gene was demonstrated by denaturing polyacrylamide gel electrophoresis and silver staining. The PGK gene products were treated with Bst XI and resolved on agarose gel. Amongst the 17 female cases of PSH, 15 samples were successfully amplified for AR and PGK genes. The rates of polymorphism were 53% (8/15) and 27% (4/15) for AR and PGK genes respectively. Polygonal cells and surface cuboidal cells of 10 cases which were suitable for clonality study, showed the same loss of alleles (clonality ratio = 0) or unbalanced methylation pattern (clonality ratio < 0.25). The polygonal cells and surface cuboidal cells in PSH demonstrate patterns of monoclonal proliferation, indicating that both represent true neoplastic cells.
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Zhang, Li; Liang, Shuli; Zhou, Xinying; Jin, Zi; Jiang, Fengchun; Han, Shuangyan; Zheng, Suiping
2013-01-01
Glycosylphosphatidylinositol (GPI)-anchored glycoproteins have various intrinsic functions in yeasts and different uses in vitro. In the present study, the genome of Pichia pastoris GS115 was screened for potential GPI-modified cell wall proteins. Fifty putative GPI-anchored proteins were selected on the basis of (i) the presence of a C-terminal GPI attachment signal sequence, (ii) the presence of an N-terminal signal sequence for secretion, and (iii) the absence of transmembrane domains in mature protein. The predicted GPI-anchored proteins were fused to an alpha-factor secretion signal as a substitute for their own N-terminal signal peptides and tagged with the chimeric reporters FLAG tag and mature Candida antarctica lipase B (CALB). The expression of fusion proteins on the cell surface of P. pastoris GS115 was determined by whole-cell flow cytometry and immunoblotting analysis of the cell wall extracts obtained by β-1,3-glucanase digestion. CALB displayed on the cell surface of P. pastoris GS115 with the predicted GPI-anchored proteins was examined on the basis of potential hydrolysis of p-nitrophenyl butyrate. Finally, 13 proteins were confirmed to be GPI-modified cell wall proteins in P. pastoris GS115, which can be used to display heterologous proteins on the yeast cell surface. PMID:23835174
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Surface characteristics of Bacillus cereus and its adhesion to stainless steel.
Peng, J S; Tsai, W C; Chou, C C
2001-04-11
The ability of a Bacillus cereus strain, isolated from spoiled milk, to adhere to the surface of stainless steel chips was evaluated during its growth in diluted tryptic soy broth (DTSB). The number of cells that adhered to the surface increased markedly as the culture reached the end of the log phase and entered stationary phase, and continued to increase with further incubation. The surface properties of cells from the log, stationary, and late stationary phases were measured by hydrophobic interaction chromatography (HIC) and electrostatic interaction chromatography (ESIC). It was found that surface hydrophobicity of B. cereus vegetative cells from the late stationary phase was the highest followed by those from the stationary phase and the log phase cultures. While the vegetative cells prepared from stationary phase and log phase cultures, respectively, had the highest and the lowest surface charges. Adhesion of B. cereus vegetative cells to stainless steel was positively correlated with the cell surface hydrophobicity (R = 0.979). Surface hydrophobicity and surface positive charge noted on the spores harvested from diluted tryptic soy agar (DTSA) and Mn2+-tryptone glucose extract agar were higher than those harvested from the sucrose or lactose-added DTSA. A wide variation in the surface charge values was noted on the surface of various spores prepared from cultures grown on the four different media tested, while their ability to adhere to stainless steel chips in phosphate buffered saline (PBS) showed no significant difference (p > 0.05). Similarly, the number of spores or vegetative cells adhering to stainless steel suspended in PBS, milk or diluted milk (1000 x) did not differ significantly (p > 0.05).
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Bioadsorption of Rare Earth Elements through Cell Surface Display of Lanthanide Binding Tags.
Park, Dan M; Reed, David W; Yung, Mimi C; Eslamimanesh, Ali; Lencka, Malgorzata M; Anderko, Andrzej; Fujita, Yoshiko; Riman, Richard E; Navrotsky, Alexandra; Jiao, Yongqin
2016-03-01
With the increasing demand for rare earth elements (REEs) in many emerging clean energy technologies, there is an urgent need for the development of new approaches for efficient REE extraction and recovery. As a step toward this goal, we genetically engineered the aerobic bacterium Caulobacter crescentus for REE adsorption through high-density cell surface display of lanthanide binding tags (LBTs) on its S-layer. The LBT-displayed strains exhibited enhanced adsorption of REEs compared to cells lacking LBT, high specificity for REEs, and an adsorption preference for REEs with small atomic radii. Adsorbed Tb(3+) could be effectively recovered using citrate, consistent with thermodynamic speciation calculations that predicted strong complexation of Tb(3+) by citrate. No reduction in Tb(3+) adsorption capacity was observed following citrate elution, enabling consecutive adsorption/desorption cycles. The LBT-displayed strain was effective for extracting REEs from the acid leachate of core samples collected at a prospective rare earth mine. Our collective results demonstrate a rapid, efficient, and reversible process for REE adsorption with potential industrial application for REE enrichment and separation.
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Yan, Tuo; Sun, Rong; Li, Chun; Tan, Baihua; Mao, Xuan; Ao, Ningjian
2010-08-01
Type-I collagen and bFGF were immobilized onto the surface of poly (HEMA-co-MMA) hydrogel by grafting and coating methods to improve its cytotoxicity. The multi-layered structure of the biocompatible layer was confirmed by FTIR, AFM and static water contact angles. The layers were stable in body-like environment (pH 7.4). Human skin fibroblast cells (HSFC) were seeded onto Col/bFGF-poly (HEMA-co-MMA), Col-poly (HEMA-co-MMA) and poly (HEMA-co-MMA) films for 1, 3 and 5 day. MTT assay was performed to evaluate the extraction toxicity of the materials. Results showed that the cell attachment, proliferation and differentiation on Col/bFGF-poly (HEMA-co-MMA) film were higher than those of the control group, which indicated the improvement of cell-material interaction. The extraction toxicity of the modified materials was also lower than that of the unmodified group. The protein and bFGF immobilized poly (HEMA-co-MMA) hydrogel might hold great promise to be a biocompatible material.
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MorphoGraphX: A platform for quantifying morphogenesis in 4D
Barbier de Reuille, Pierre; Routier-Kierzkowska, Anne-Lise; Kierzkowski, Daniel; Bassel, George W; Schüpbach, Thierry; Tauriello, Gerardo; Bajpai, Namrata; Strauss, Sören; Weber, Alain; Kiss, Annamaria; Burian, Agata; Hofhuis, Hugo; Sapala, Aleksandra; Lipowczan, Marcin; Heimlicher, Maria B; Robinson, Sarah; Bayer, Emmanuelle M; Basler, Konrad; Koumoutsakos, Petros; Roeder, Adrienne HK; Aegerter-Wilmsen, Tinri; Nakayama, Naomi; Tsiantis, Miltos; Hay, Angela; Kwiatkowska, Dorota; Xenarios, Ioannis; Kuhlemeier, Cris; Smith, Richard S
2015-01-01
Morphogenesis emerges from complex multiscale interactions between genetic and mechanical processes. To understand these processes, the evolution of cell shape, proliferation and gene expression must be quantified. This quantification is usually performed either in full 3D, which is computationally expensive and technically challenging, or on 2D planar projections, which introduces geometrical artifacts on highly curved organs. Here we present MorphoGraphX (www.MorphoGraphX.org), a software that bridges this gap by working directly with curved surface images extracted from 3D data. In addition to traditional 3D image analysis, we have developed algorithms to operate on curved surfaces, such as cell segmentation, lineage tracking and fluorescence signal quantification. The software's modular design makes it easy to include existing libraries, or to implement new algorithms. Cell geometries extracted with MorphoGraphX can be exported and used as templates for simulation models, providing a powerful platform to investigate the interactions between shape, genes and growth. DOI: http://dx.doi.org/10.7554/eLife.05864.001 PMID:25946108
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Bioadsorption of rare earth elements through cell surface display of lanthanide binding tags
Park, Dan M.; Reed, David W.; Yung, Mimi C.; ...
2016-02-02
In this study, with the increasing demand for rare earth elements (REEs) in many emerging clean energy technologies, there is an urgent need for the development of new approaches for efficient REE extraction and recovery. As a step toward this goal, we genetically engineered the aerobic bacterium Caulobacter crescentus for REE adsorption through high-density cell surface display of lanthanide binding tags (LBTs) on its S-layer. The LBT-displayed strains exhibited enhanced adsorption of REEs compared to cells lacking LBT, high specificity for REEs, and an adsorption preference for REEs with small atomic radii. Adsorbed Tb 3+ could be effectively recovered usingmore » citrate, consistent with thermodynamic speciation calculations that predicted strong complexation of Tb 3+ by citrate. No reduction in Tb 3+ adsorption capacity was observed following citrate elution, enabling consecutive adsorption/desorption cycles. The LBT-displayed strain was effective for extracting REEs from the acid leachate of core samples collected at a prospective rare earth mine. Our collective results demonstrate a rapid, efficient, and reversible process for REE adsorption with potential industrial application for REE enrichment and separation.« less
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Xue, Yingying; Qian, Chen; Wang, Zhilong; Xu, Jian-He; Yang, Rude; Qi, Hanshi
2010-01-01
Extractive microbial transformation of L-phenylacetylcarbinol (L-PAC) in nonionic surfactant Triton X-100 micelle aqueous solution was investigated by response surface methodology. Based on the Box-Behnken design, a mathematical model was developed for the predication of mutual interactions between benzaldehyde, Triton X-100, and glucose on L-PAC production. It indicated that the negative or positive effect of nonionic surfactant strongly depended on the substrate concentration. The model predicted that the optimal concentration of benzaldehyde, Triton X-100, and glucose was 1.2 ml, 15 g, and 2.76 g per 100 ml, respectively. Under the optimal condition, the maximum L-PAC production was 27.6 mM, which was verified by a time course of extractive microbial transformation. A discrete fed-batch process for verification of cell activity was also presented.
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Ligand Extraction Properties of the GM2 Activator Protein and Its Interactions with Lipid Vesicles
Ran, Yong; Fanucci, Gail E.
2009-01-01
Abstract The GM2 activator protein (GM2AP) is an accessory protein required for the enzymatic conversion of GM2 to GM3 by hydrolases in the lysosomal compartments of cells. Here, GM2AP interactions with lipid vesicles are investigated by sucrose-loaded vesicle sedimentation and gel filtration assays, and the effects of pH and lipid composition on membrane binding and lipid extraction are characterized. The sedimentation experiments allow for facile quantification of the percentage of protein in solution and on the bilayer surface, with detailed analysis of the protein:lipid complex that remains in solution. Optimum binding and ligand extraction is found for pH 4.8 where <15% of the protein remains surface associated regardless of the lipid composition. In addition to extracting GM2, we find that GM2AP readily extracts dansyl-headgroup-labeled lipids as well as other phospholipids from vesicles. The ability of GM2AP to extract dansyl-DHPE from vesicles is altered by pH and the specific ligand GM2. Although the unique endosomal lipid, bis(monoacylglycero)phosphate, is not required for ligand extraction, it does enhance the extraction efficiency of GM2 when cholesterol is present in the vesicles. PMID:19580763
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Ligand extraction properties of the GM2 activator protein and its interactions with lipid vesicles.
Ran, Yong; Fanucci, Gail E
2009-07-08
The GM2 activator protein (GM2AP) is an accessory protein required for the enzymatic conversion of GM2 to GM3 by hydrolases in the lysosomal compartments of cells. Here, GM2AP interactions with lipid vesicles are investigated by sucrose-loaded vesicle sedimentation and gel filtration assays, and the effects of pH and lipid composition on membrane binding and lipid extraction are characterized. The sedimentation experiments allow for facile quantification of the percentage of protein in solution and on the bilayer surface, with detailed analysis of the protein:lipid complex that remains in solution. Optimum binding and ligand extraction is found for pH 4.8 where <15% of the protein remains surface associated regardless of the lipid composition. In addition to extracting GM2, we find that GM2AP readily extracts dansyl-headgroup-labeled lipids as well as other phospholipids from vesicles. The ability of GM2AP to extract dansyl-DHPE from vesicles is altered by pH and the specific ligand GM2. Although the unique endosomal lipid, bis(monoacylglycero)phosphate, is not required for ligand extraction, it does enhance the extraction efficiency of GM2 when cholesterol is present in the vesicles.
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Single-cell force spectroscopy of pili-mediated adhesion
NASA Astrophysics Data System (ADS)
Sullan, Ruby May A.; Beaussart, Audrey; Tripathi, Prachi; Derclaye, Sylvie; El-Kirat-Chatel, Sofiane; Li, James K.; Schneider, Yves-Jacques; Vanderleyden, Jos; Lebeer, Sarah; Dufrêne, Yves F.
2013-12-01
Although bacterial pili are known to mediate cell adhesion to a variety of substrates, the molecular interactions behind this process are poorly understood. We report the direct measurement of the forces guiding pili-mediated adhesion, focusing on the medically important probiotic bacterium Lactobacillus rhamnosus GG (LGG). Using non-invasive single-cell force spectroscopy (SCFS), we quantify the adhesion forces between individual bacteria and biotic (mucin, intestinal cells) or abiotic (hydrophobic monolayers) surfaces. On hydrophobic surfaces, bacterial pili strengthen adhesion through remarkable nanospring properties, which - presumably - enable the bacteria to resist high shear forces under physiological conditions. On mucin, nanosprings are more frequent and adhesion forces larger, reflecting the influence of specific pili-mucin bonds. Interestingly, these mechanical responses are no longer observed on human intestinal Caco-2 cells. Rather, force curves exhibit constant force plateaus with extended ruptures reflecting the extraction of membrane nanotethers. These single-cell analyses provide novel insights into the molecular mechanisms by which piliated bacteria colonize surfaces (nanosprings, nanotethers), and offer exciting avenues in nanomedicine for understanding and controlling the adhesion of microbial cells (probiotics, pathogens).
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NASA Astrophysics Data System (ADS)
Maurya, Ishwar Chandra; Singh, Shalini; Neetu; Gupta, Arun Kumar; Srivastava, Pankaj; Bahadur, Lal
2018-01-01
Natural dyes extracted from four different flowers, namely, Cassia surattensis, Cassia tora, Cassia alata and Cassia occidentalis were used as sensitizers for TiO2-based dye-sensitized solar cells (DSSC). The dye extracts from flowers were obtained by a simple extraction technique and used without any further purification. Optical characteristics of dye extracts were studied. Fourier-transform infrared (FTIR) spectra were used to identify the constituents of extracted dyes. The photovoltaic performance of DSSC employing dye-capped TiO2 photoanodes was measured. The sensitization performance related to anchoring groups present and interaction between dyes with TiO2 surface is demonstrated. An attempt has been made to rationalize the observations by light absorption of the dye extracts and their adsorption on TiO2. The short-circuit current density ( I SC) values ranged from 0.06 mA/cm2 to 0.20 mA/cm2; open circuit voltage ( V OC) from 0.292 V to 0.833 V; fill factor (FF) from 0.7 to 0.9; efficiencies ( η) from 0.013% to 0.15% and incident photon-to-current conversion efficiency from 13% to 20%, were obtained for DSSC using these natural dye extracts. Cassia occidentalis showed the highest current density of 0.20 mA/cm2 and power conversion efficiency of 0.15%, which was due to better interaction between the carbonyl and hydroxyl group of the anthocyanin molecule of C. occidentalis and surface of TiO2 film. The red and blue shift of absorption wavelength of C. surattensis and the blue shift of absorption wavelength of the C. tora, C. alata and C. occidentalis extract in ethanol solution compared to that on TiO2 film has been used for the interpretation of obtained results.
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Stravs, Michael A; Mechelke, Jonas; Ferguson, P Lee; Singer, Heinz; Hollender, Juliane
2016-03-01
Online solid-phase extraction was combined with nano-liquid chromatography coupled to high-resolution mass spectrometry (HRMS) for the analysis of micropollutants in environmental samples from small volumes. The method was validated in surface water, Microcystis aeruginosa cell lysate, and spent Microcystis growth medium. For 41 analytes, quantification limits of 0.1-28 ng/L (surface water) and 0.1-32 ng/L (growth medium) were obtained from only 88 μL of sample. In cell lysate, quantification limits ranged from 0.1-143 ng/L or 0.33-476 ng/g dry weight from a sample of 88 μL, or 26 μg dry weight, respectively. The method matches the sensitivity of established online and offline solid-phase extraction-liquid chromatography-mass spectrometry methods but requires only a fraction of the sample used by those techniques, and is among the first applications of nano-LC-MS for environmental analysis. The method was applied to the determination of bioconcentration in Microcystis aeruginosa in a laboratory experiment, and the benefit of coupling to HRMS was demonstrated in a transformation product screening.
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von Wurmb-Schwark, Nicole; Mályusz, Victoria; Fremdt, Heike; Koch, Christine; Simeoni, Eva; Schwark, Thorsten
2006-05-01
The forensic scientist often has to cope with problematic samples from the crime scene due to their minute size and thus the low amount of extractable DNA. The retrieval of DNA from swabs taken from the surface of the skin, for example, in cases of strangulation, can be especially difficult. We systematically investigated swabs taken from the skin (to obtain a genetic profile from the victim and also from a possible offender) and from sperm cell containing swabs using two extraction kits: the Invisorb forensic and the Invisorb spin swab kit (both Invitek, Germany). DNA quality and quantity were tested on ethidium bromide containing agarose gels and in a highly sensitive duplex-PCR, which amplifies fragments specific for mitochondrial and nuclear DNA. Absolute quantification was done using real time PCR. Samples, which were positive in the duplex-PCR, were also employed to genetic fingerprinting using the Powerplex ES and the AmpFlSTRIdentifiler(TM) kits. Our study shows that the easy-to-use Invisorb spin swab kit is very suitable for DNA isolation from swabs taken from the skin and also from sperm cells. Retrieval of cells from the skin with swabs moistened in extraction buffer, not in distilled water, led to a significant higher DNA yield.
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Extractable Bacterial Surface Proteins in Probiotic–Host Interaction
do Carmo, Fillipe L. R.; Rabah, Houem; De Oliveira Carvalho, Rodrigo D.; Gaucher, Floriane; Cordeiro, Barbara F.; da Silva, Sara H.; Le Loir, Yves; Azevedo, Vasco; Jan, Gwénaël
2018-01-01
Some Gram-positive bacteria, including probiotic ones, are covered with an external proteinaceous layer called a surface-layer. Described as a paracrystalline layer and formed by the self-assembly of a surface-layer-protein (Slp), this optional structure is peculiar. The surface layer per se is conserved and encountered in many prokaryotes. However, the sequence of the corresponding Slp protein is highly variable among bacterial species, or even among strains of the same species. Other proteins, including surface layer associated proteins (SLAPs), and other non-covalently surface-bound proteins may also be extracted with this surface structure. They can be involved a various functions. In probiotic Gram-positives, they were shown by different authors and experimental approaches to play a role in key interactions with the host. Depending on the species, and sometime on the strain, they can be involved in stress tolerance, in survival within the host digestive tract, in adhesion to host cells or mucus, or in the modulation of intestinal inflammation. Future trends include the valorization of their properties in the formation of nanoparticles, coating and encapsulation, and in the development of new vaccines. PMID:29670603
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Ancient microbes from halite fluid inclusions: optimized surface sterilization and DNA extraction.
Sankaranarayanan, Krithivasan; Timofeeff, Michael N; Spathis, Rita; Lowenstein, Tim K; Lum, J Koji
2011-01-01
Fluid inclusions in evaporite minerals (halite, gypsum, etc.) potentially preserve genetic records of microbial diversity and changing environmental conditions of Earth's hydrosphere for nearly one billion years. Here we describe a robust protocol for surface sterilization and retrieval of DNA from fluid inclusions in halite that, unlike previously published methods, guarantees removal of potentially contaminating surface-bound DNA. The protocol involves microscopic visualization of cell structures, deliberate surface contamination followed by surface sterilization with acid and bleach washes, and DNA extraction using Amicon centrifugal filters. Methods were verified on halite crystals of four different ages from Saline Valley, California (modern, 36 ka, 64 ka, and 150 ka), with retrieval of algal and archaeal DNA, and characterization of the algal community using ITS1 sequences. The protocol we developed opens up new avenues for study of ancient microbial ecosystems in fluid inclusions, understanding microbial evolution across geological time, and investigating the antiquity of life on earth and other parts of the solar system.
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NASA Astrophysics Data System (ADS)
Ramaswamy, Sriram
2007-03-01
Collections of self-driven or ``active'' particles are now recognised as a distinct kind of nonequilibrium matter, and an understanding of their phases, hydrodynamics, mechanical response, and correlations is a vital and rapidly developing part of the statistical physics of soft-matter systems far from equilibrium. My talk will review our recent results, from theory, simulation and experiment, on order, fluctuations, and flow instabilities in collections of active particles, in suspension or on a solid surface. Our work, which began by adapting theories of flocking to include the hydrodynamics of the ambient fluid, provides the theoretical framework for understanding active matter in all its diversity: contractile filaments in cell extracts, crawling or dividing cells, collectively swimming bacteria, fish schools, and agitated monolayers of orientable granular particles.
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Gurunathan, Sangiliyandi; Han, Jaewoong; Park, Jung Hyun; Kim, Jin Hoi
2014-01-01
Recently, graphene and graphene-related materials have attracted much attention due their unique properties, such as their physical, chemical, and biocompatibility properties. This study aimed to determine the cytotoxic effects of graphene oxide (GO) that is reduced biologically using Ganoderma spp. mushroom extracts in MDA-MB-231 human breast cancer cells. Herein, we describe a facile and green method for the reduction of GO using extracts of Ganoderma spp. as a reducing agent. GO was reduced without any hazardous chemicals in an aqueous solution, and the reduced GO was characterized using a range of analytical procedures. The Ganoderma extract (GE)-reduced GO (GE-rGO) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, dynamic light scattering, scanning electron microscopy, Raman spectroscopy, and atomic force microscopy. Furthermore, the toxicity of GE-rGO was evaluated using a sequence of assays such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation in human breast cancer cells (MDA-MB-231). The preliminary characterization of reduction of GO was confirmed by the red-shifting of the absorption peak for GE-rGO to 265 nm from 230 nm. The size of GO and GE-rGO was found to be 1,880 and 3,200 nm, respectively. X-ray diffraction results confirmed that reduction processes of GO and the processes of removing intercalated water molecules and the oxide groups. The surface functionalities and chemical natures of GO and GE-rGO were confirmed using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface morphologies of the synthesized graphene were analyzed using high-resolution scanning electron microscopy. Raman spectroscopy revealed single- and multilayer properties of GE-rGO. Atomic force microscopy images provided evidence for the formation of graphene. Furthermore, the effect of GO and GE-rGO was examined using a series of assays, such as cell viability, membrane integrity, and reactive oxygen species generation, which are key molecules involved in apoptosis. The results obtained from cell viability and lactate dehydrogenase assay suggest that GO and GE-rGO cause dose-dependent toxicity in the cells. Interestingly, it was found that biologically derived GE-rGO is more toxic to cancer cells than GO. We describe a simple, green, nontoxic, and cost-effective approach to producing graphene using mushroom extract as a reducing and stabilizing agent. The proposed method could enable synthesis of graphene with potential biological and biomedical applications such as in cancer and angiogenic disorders. To our knowledge, this is the first report using mushroom extract as a reducing agent for the synthesis of graphene. Mushroom extract can be used as a biocatalyst for the production of graphene.
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Proteoglycan 4 (PRG4) synthesis and immunolocalization in bovine meniscus.
Schumacher, Barbara L; Schmidt, Tannin A; Voegtline, Michael S; Chen, Albert C; Sah, Robert L
2005-05-01
Proteoglycan 4 (PRG4) is synthesized and secreted into the synovial fluid by articular chondrocytes and synovial cells, lining the cavity of joints. A thin layer of PRG4 is also present at the articular surface, where it appears to be involved in boundary lubrication. This study investigated if PRG4 is also synthesized and secreted by the cells within meniscus, and if PRG4 is also present in, and at the surface of, meniscus. PRG4 was visualized in sections of bovine calf menisci by immunohistochemistry. PRG4 was detected in two regions: (1) at the femoral and tibial surfaces of the meniscus, and within cells below these surfaces; and (2) within and near cells along the radial tie fibers and circumferential fibers. From meniscus tissue harvested from these surfaces, PRG4 was extracted with 4M GuHCl and quantified by ELISA. There was 0.20 +/- 0.01 and 0.25 +/- 0.04 microg PRG4/cm(2) area of lateral and medial meniscus surface, respectively. ELISA analysis of spent medium from other samples of meniscus surface tissue incubated in medium supplemented with serum and ascorbate showed that 8.1 +/- 1.1 microg PRG4/cm(2) area of meniscus surface was secreted over six days. These results demonstrate that PRG4 is synthesized and secreted by certain cell populations in the meniscus, and that PRG4 is present in the meniscus at surfaces and also internal fibers where it may contribute to boundary lubrication.
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Li, Xiaojia; Horishita, Takafumi; Toyohira, Yumiko; Shao, Hui; Bai, Jie; Bo, Haixia; Song, Xinbo; Ishikane, Shin; Yoshinaga, Yukari; Satoh, Noriaki; Tsutsui, Masato; Yanagihara, Nobuyuki
2017-04-01
Extract of pine nodules (matsufushi) formed by bark proliferation on the surface of trees of Pinus tabulaeformis or Pinus massoniana has been used as an analgesic for joint pain, rheumatism, neuralgia, dysmenorrhea and other complaints in Chinese traditional medicine. Here we report the effects of matsufushi extract and its components on catecholamine secretion and synthesis in cultured bovine adrenal medullary cells. We found that matsufushi extract (0.0003-0.005%) and its component, SJ-2 (5-hydroxy-3-methoxy-trans-stilbene) (0.3-100 μM), but not the other three, concentration-dependently inhibited catecholamine secretion induced by acetylcholine, a physiological secretagogue. Matsufushi extract (0.0003-0.005%) and SJ-2 (0.3-100 μM) also inhibited 45 Ca 2+ influx induced by acetylcholine in a concentration-dependent manner, similar to its effect on catecholamine secretion. They also suppressed 14 C-catecholamine synthesis and tyrosine hydroxylase activity induced by acetylcholine. In Xenopus oocytes expressing α3β4 nicotinic acetylcholine receptors, matsufushi extract (0.00003-0.001%) and SJ-2 (1-100 μM) directly inhibited the current evoked by acetylcholine. The present findings suggest that SJ-2, as well as matsufushi extract, inhibits acetylcholine-induced catecholamine secretion and synthesis by suppression of nicotinic acetylcholine receptor-ion channels in bovine adrenal medullary cells. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
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Statistical optimisation of cell growth and carotenoid production by rhodotorula mucilaginosa
Maldonade, Iriani R.; Rodriguez-Amaya, Delia B.; Scamparini, Adilma R. P.
2012-01-01
Sequential statistical methods were used to maximise carotenoid production by a strain of Rhodotorula mucilaginosa, isolated from the Brazilian ecosystem. Initially, a factorial 25–1 experimental design was used, and the variables were pH and the levels of glucose, yeast extract, MgSO4.7H2O and KH2PO4. The nitrogen source (yeast extract) was the most important variable in enhancing carotenoid production; MgSO4.7H2O and KH2PO4 had a negative influence. The initial pH had no significant effect on carotenoid and cell productions. We further investigated the effects of glucose and yeast extract effects, using a second-order central composite design (CCD) to optimise carotenoid production, which was adequately approximated with a full quadratic equation obtained from a two-factor-2-level design. The analysis of quadratic surfaces showed that after 5 days of cultivation at 25 °C, the maximum carotenoid concentration (745 µg l-1) was obtained with 15 g l-1 of yeast extract and 20 g l-1 of glucose. The maximum carotenoid production (152 µg g-1) was obtained with 5 g l-1 yeast extract and 10 g l-1 glucose. Carotenoid formation was more sensitive to changes in yeast extract concentration than to changes in glucose concentration. Maximum cell production was achieved with 15–17 g l-1 of yeast extract and 15–20 g l-1 of glucose. PMID:24031809
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Soares, Diana Gabriela; Pastana, Júlia Vieira; de Oliveira Duque, Carla Caroline; Dias Ribeiro, Ana Paula; Basso, Fernanda Gonçalves; Hebling, Josimeri; de Souza Costa, Carlos Alberto
2014-04-01
To assess the influence of adhesive restorations on hydrogen peroxide (H2O2) diffusion through enamel and dentin and its cytotoxicity to pulp (MDPC-23) cells. Sound and resin-restored enamel/dentin disks were stored in water for 24 h or 6 months and adapted to artificial pulp chambers. Bleaching gels with 20% or 35% H2O2 were applied to the enamel surface for 45 min, and a culture medium in direct contact with the dentin surface (extract) was applied for 1 h to the MDPC-23 cells. Cell metabolism (MTT assay) and cell morphology (SEM) were assessed. The amount of H2O2 in the extracts was also quantified (peroxidase/leuco-crystal violet reaction). A significant reduction in cell metabolism was observed between the group bleached with the 35% gel and the control group (sound, nonbleached) (p < 0.05). The H2O2 diffusion was directly related to its concentration in the bleaching gel. The variables "presence of restoration" and "time of water storage" did not significantly influence H2O2 diffusion or cell metabolism for either of the bleaching gels (p > 0.05). All bleached groups presented alterations in cell morphology related to the concentration of H2O2 in the bleaching gel. The reduction in cell metabolism and the changes in cell morphology were H2O2-concentration dependent, having no relationship with the presence of either new or aged adhesive restorations on teeth subjected to bleaching therapies.
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Status and Perspectives of Ion Track Electronics for Advanced Biosensing
NASA Astrophysics Data System (ADS)
Fink, D.; Muñoz, H. Gerardo; Alfonta, L.; Mandabi, Y.; Dias, J. F.; de Souza, C. T.; Bacakova, L. E.; Vacík, J.; Hnatowicz, V.; Kiv, A. E.; Fuks, D.; Papaleo, R. M.
New multifunctional ion irradiation-based three-dimensional electronic structures are developed for biotechnological applications, specifically for sensing of biomaterials, bacteria and mammalian cells. This is accomplished by combined micrometric surface and nanometric bulk microstructuring of insulators (specifically of polymer foils and SiO2/Si hybride structures) by adequate ion beams. Our main goal is the production of a cheap small universal generic working platform with multifunctional properties for biomedical analysis. Surface engineering of this platform enables cell bonding and its bulk engineering enables the extraction of cell secrets, for the sake of intercepting and analyzing the biomolecules used in cell communication. The exact knowledge of the spectrum of these cell-secreted signalling molecules should enable one to identify unambiguously the cell type. This knowledge will help developing strategies for preventive quorum sensing of bacteria, with the aim of fighting bacterial infections in an ecologically secure way.
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Cytotoxicity assessment of modified bioactive glasses with MLO-A5 osteogenic cells in vitro.
Modglin, Vernon C; Brown, Roger F; Jung, Steven B; Day, Delbert E
2013-05-01
The primary objective of this study was to evaluate in vitro responses of MLO-A5 osteogenic cells to two modifications of the bioactive glass 13-93. The modified glasses, which were designed for use as cell support scaffolds and contained added boron to form the glasses 13-93 B1 and 13-93 B3, were made to accelerate formation of a bioactive hydroxyapatite surface layer and possibly enhance tissue growth. Quantitative MTT cytotoxicity tests revealed no inhibition of growth of MLO-A5 cells incubated with 13-93 glass extracts up to 10 mg/ml, moderate inhibition of growth with 13-93 B1 glass extracts, and noticeable inhibition of growth with 13-93 B3 glass extracts. A morphology-based biocompatibility test was also performed and yielded qualitative assessments of the relative biocompatibilities of glass extracts that agree with those obtained by the quantitative MTT test. However, as a proof of concept experiment, when MLO-A5 cells were seeded onto 13-93 B3 scaffolds in a dynamic in vitro environment, cell proliferation occurred as evidenced by qualitative and quantitative MTT labeling of scaffolds. Together these results demonstrate the in vitro toxicity of released borate ion in static experiments; however borate ion release can be mitigated in a dynamic environment similar to the human body where microvasculature is present. Here we argue that despite toxicity in static environments, boron-containing 13-93 compositions may warrant further study for use in tissue engineering applications.
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Hu, Lijun; Sun, Kuan; Wang, Ming; Chen, Wei; Yang, Bo; Fu, Jiehao; Xiong, Zhuang; Li, Xinyi; Tang, Xiaosheng; Zang, Zhigang; Zhang, Shupeng; Sun, Lidong; Li, Meng
2017-12-20
The performance of inverted perovskite solar cells is highly dependent on hole extraction and surface properties of hole transport layers. To highlight the important role of hole transport layers, a facile and simple method is developed by adding sodium chloride (NaCl) into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The average power conversion efficiency of the perovskite solar cells prepared on NaCl-doped PEDOT:PSS is 17.1% with negligible hysteresis, compared favorably to the control devices (15.1%). Particularly, they exhibit markedly improved V oc and fill factor (FF), with the best FF as high as 81.9%. The enhancement of photovoltaic performance is ascribed to two effects. Better conductivity and hole extraction of PEDOT:PSS are observed after NaCl doping. More intriguingly, the perovskite polycrystalline film shows a preferred orientation along the (001) direction on NaCl-doped PEDOT:PSS, leading to a more uniform thin film. The comparison of the crystal structure between NaCl and MAPbCl 3 indicates a lattice constant mismatch less than 2% and a matched chlorine atom arrangement on the (001) surface, which implies that the NaCl crystallites on the top surface of PEDOT:PSS might serve as seeds guiding the growth of perovskite crystals. This simple method is fully compatible with printing technologies to mass-produce perovskite solar cells with high efficiency and tunable crystal orientations.
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Zhang, Hai-Lin; Cui, Shao-Hua; Zha, Xue-Qiang; Bansal, Vibha; Xue, Lei; Li, Xiao-Long; Hao, Ran; Pan, Li-Hua; Luo, Jian-Ping
2014-06-15
In this work, response surface methodology was used to determine optimum conditions for extraction of polysaccharides from jellyfish skin (JSP). The optimum parameters were found to be raw material to water ratio 1:7.5 (w/v), extraction temperature 100°C and extraction time 4h. Under these conditions, the JSP yield reached 1.007 mg/g. Papain (15 U/mL) in combination with Sevag reagent was beneficial in removing proteins from JSP. After precipitation with ethanol at final concentration of 40%, 60% and 80% in turn, three polysaccharide fractions of JSP1, JSP2 and JSP3 were obtained from JSP, respectively. The three fractions exhibited different physicochemical properties with respect to molecular weight distribution, monosaccharide composition, infrared absorption spectra, and glycosyl bond composition. In addition, JSP3 showed strong inhibitory effects on oxidized low-density lipoprotein (oxLDL) induced conversion of macrophages into foam cells, which possibly attributed to the down-regulation of some atherogenesis-related gene expressions. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Vilardell, A M; Cinca, N; Garcia-Giralt, N; Dosta, S; Cano, I G; Nogués, X; Guilemany, J M
2018-06-01
Three different surface treatments on a Ti6Al4V alloy have been in vitro tested for possible application in cementless joint prosthesis. All of them involve the novelty of using the Cold Spray technology for their deposition: (i) an as-sprayed highly rough titanium and, followed by the deposition of a thin hydroxyapatite layer with (ii) microcrystalline or (iii) nanocrystalline structure. Primary human osteoblasts were extracted from knee and seeded onto the three different surfaces. Cell viability was tested by MTS and LIVE/DEAD assays, cell differentiation by alkaline phosphatase (ALP) quantification and cell morphology by Phalloidin staining. All tests were carried out at 1, 7 and 14 days of cell culture. Different cell morphologies between titanium and hydroxyapatite surfaces were exhibited. At 1 day of cell culture, cells on the titanium coating were spread and flattened, expanding the filopodia actin filaments in all directions, while cells on the hydroxyapatite coatings showed round like-shape morphology due to slower attachment. Higher cell viability was detected at all times of cell culture on titanium coating due to a better attachment at 1 day. However, from 7 days of cell culture, cells on hydroxyapatite showed good attachment onto surfaces and highly increased their proliferation, mostly on nanocrystalline, achieving similar cell viability levels than titanium coatings. ALP levels were significantly higher in titanium, in part, because of greatest cell number. Overall, the best cell functional results were obtained on titanium coatings whereas microcrystalline hydroxyapatite presented the worst cellular parameters. However, results indicate that nanocrystalline hydroxyapatite coatings may achieve promising results for the faster cell proliferation once cells are attached on the surface. Copyright © 2018 Elsevier B.V. All rights reserved.
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Carlson, Hans K.; Iavarone, Anthony T.; Gorur, Amita; Yeo, Boon Siang; Tran, Rosalie; Melnyk, Ryan A.; Mathies, Richard A.; Auer, Manfred; Coates, John D.
2012-01-01
Almost nothing is known about the mechanisms of dissimilatory metal reduction by Gram-positive bacteria, although they may be the dominant species in some environments. Thermincola potens strain JR was isolated from the anode of a microbial fuel cell inoculated with anaerobic digester sludge and operated at 55 °C. Preliminary characterization revealed that T. potens coupled acetate oxidation to the reduction of hydrous ferric oxides (HFO) or anthraquinone-2,6-disulfonate (AQDS), an analog of the redox active components of humic substances. The genome of T. potens was recently sequenced, and the abundance of multiheme c-type cytochromes (MHCs) is unusual for a Gram-positive bacterium. We present evidence from trypsin-shaving LC-MS/MS experiments and surface-enhanced Raman spectroscopy (SERS) that indicates the expression of a number of MHCs during T. potens growth on either HFO or AQDS, and that several MHCs are localized to the cell wall or cell surface. Furthermore, one of the MHCs can be extracted from cells with low pH or denaturants, suggesting a loose association with the cell wall or cell surface. Electron microscopy does not reveal an S-layer, and the precipitation of silver metal on the cell surface is inhibited by cyanide, supporting the involvement of surface-localized redox-active heme proteins in dissimilatory metal reduction. These results provide unique direct evidence for cell wall-associated cytochromes and support MHC involvement in conducting electrons across the cell envelope of a Gram-positive bacterium. PMID:22307634
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Osseointegrated dental implants produced via microwave processing
NASA Astrophysics Data System (ADS)
Kutty, Muralithran G.
This research is a comprehensive effort to develop osseointegrated dental implants via microwave processing. A net-shape microwave sintering procedure was employed to fabricate dental implants. Commercial pure titanium powders (-100, -200 and -325 mesh sizes) were used in this work. This process eliminates the need for machining of implants and prevents contamination. The idea was to take advantage of the peculiar way microwave couple with metallic powders, i.e. generating heat in the interior of the sample and dissipating it away through the surface. The desired features for an implant, a dense core with surface pores, is not possible via conventional sintering. Coating with hydroxyapatite via electrodeposition and chemical combustion vapor deposition was also attempted to further enhance the bioactivity of this layer. Surface roughness and area were measured using a non-contact surface profilometer to further describe the unique surface. In-vitro studies, conducted using osteoblast cells extracted from neonatal rat calvarial, showed improved cell growth on all the uncoated porous samples. However, the highest cell growth was observed on the -200 mesh size samples. The higher surface area of the -200 mesh samples is attributed to this observation. This work was able to identify the processing parameters for titanium in microwave and establishes the importance of surface area as a key parameter for cell growth on porous surfaces as compared to surface roughness.
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Wang, Da-Zhi; Dong, Hong-Po; Li, Cheng; Xie, Zhang-Xian; Lin, Lin; Hong, Hua-Sheng
2011-01-01
The cell wall is an important subcellular component of dinoflagellate cells with regard to various aspects of cell surface-associated ecophysiology, but the full range of cell wall proteins (CWPs) and their functions remain to be elucidated. This study identified and characterized CWPs of a toxic dinoflagellate, Alexandrium catenella, using a combination of 2D fluorescence difference gel electrophoresis (DIGE) and MALDI TOF-TOF mass spectrometry approaches. Using sequential extraction and temperature shock methods, sequentially extracted CWPs and protoplast proteins, respectively, were separated from A. catenella. From the comparison between sequentially extracted CWPs labeled with Cy3 and protoplast proteins labeled with Cy5, 120 CWPs were confidently identified in the 2D DIGE gel. These proteins gave positive identification of protein orthologues in the protein database using de novo sequence analysis and homology-based search. The majority of the prominent CWPs identified were hypothetical or putative proteins with unknown function or no annotation, while cell wall modification enzymes, cell wall structural proteins, transporter/binding proteins, and signaling and defense proteins were tentatively identified in agreement with the expected role of the extracellular matrix in cell physiology. This work represents the first attempt to investigate dinoflagellate CWPs and provides a potential tool for future comprehensive characterization of dinoflagellate CWPs and elucidation of their physiological functions. PMID:21904561
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The Voltage Boost Enabled by Luminescence Extraction in Solar Cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ganapati, Vidya; Steiner, Myles A.; Yablonovitch, Eli
A new physical principle has emerged to produce record voltages and efficiencies in photovoltaic cells, 'luminescence extraction.' This is exemplified by the mantra 'a good solar cell should also be a good LED.' Luminescence extraction is the escape of internal photons out of the front surface of a solar cell. Basic thermodynamics says that the voltage boost should be related to concentration ratio, C, of a resource by ..delta..V=(kT/q)ln{C}. In light trapping, (i.e. when the solar cell is textured and has a perfect back mirror) the concentration ratio of photons C={4n2}, so one would expect a voltage boost of ..delta..V=kTmore » ln{4n2} over a solar cell with no texture and zero back reflectivity, where n is the refractive index. Nevertheless, there has been ambiguity over the voltage benefit to be expected from perfect luminescence extraction. Do we gain an open circuit voltage boost of ..delta..V=(kT/q)ln{n2}, ..delta..V=(kT/q)ln{2n2}, or ..delta..V=(kT/q)ln{4n2}? What is responsible for this voltage ambiguity ..delta..V=(kT/q)ln{4}=36mVolts? We show that different results come about, depending on whether the photovoltaic cell is optically thin or thick to its internal luminescence. In realistic intermediate cases of optical thickness the voltage boost falls in between; ln{n2}q..delta..V/kT)<;ln{4n2}.« less
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Wu, Shu-Jing; Ng, Lean-Teik; Chen, Ching-Hsein; Lin, Doung-Liang; Wang, Shyh-Shyan; Lin, Chun-Ching
2004-03-05
Physalis angulata and P. peruviana are herbs widely used in folk medicine. In this study, the aqueous and ethanol extracts prepared from the whole plant of these species were evaluated for their antihepatoma activity. Using XTT assay, three human hepatoma cells, namely Hep G2, Hep 3B and PLC/PRF/5 were tested. The results showed that ethanol extract of P. peruviana (EEPP) possessed the lowest IC50 value against the Hep G2 cells. Interestingly, all extracts showed no cytotoxic effect on normal mouse liver cells. Treatment with carbonyl cyanide m-chlorophenyl hydrazone, a protonophore, caused a reduction of membrane potential (Deltapsim) by mitochondrial membrane depolarization. At high concentrations, EEPP was shown to induce cell cycle arrest and apoptosis through mitochondrial dysfunction as demonstrated by the following observations: (i) EEPP induced the collapse of Deltapsim and the depletion of glutathione content in a dose dependent manner; (ii) pretreatment with the antioxidant (1.0 microg/ml vitamin E) protected cells from EEPP-induced release of ROS; and (iii) at concentrations 10 to 50 microg/ml, EEPP displayed a dose-dependent accumulation of the Sub-G1 peak (hypoploid) and caused G0/G1-phase arrest. Apoptosis was elicited when the cells were treated with 50 microg/ml EEPP as characterized by the appearance of phosphatidylserine on the outer surface of the plasma membrane. The results conclude that EEPP possesses potent antihepatoma activity and its effect on apoptosis is associated with mitochondrial dysfunction.
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Cytotoxicity and antimicrobial activities of green synthesized silver nanoparticles.
Lokina, S; Stephen, A; Kaviyarasan, V; Arulvasu, C; Narayanan, V
2014-04-09
Bio-inspired silver nanoparticles are synthesized using Malus domestica (apple) extract. Polyphenols present in the apple extract act as a reducing and capping agent to produce the silver nanoparticles. UV-Visible analysis shows the surface plasmon resonance (SPR) absorption at 420 nm. The FTIR analysis was used to identify the functional groups responsible for the bio-reduction of silver ion. The XRD and HRTEM images confirm the formation of silver nanoparticles. The minimal inhibitory concentration (MIC) of silver nanoparticles was recorded against most of the bacteria and fungus. Further, MCF-7 human breast adenocarcinoma cancer cell line was employed to observe the efficacy of cancer cell killing. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
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Abdulbaqi, Hayder Raad; Himratul-Aznita, Wan Harun; Baharuddin, Nor Adinar
2016-10-01
Green tea (Gt), leafs of Camellia sinensis var. assamica, is widely consumed as healthy beverage since thousands of years in Asian countries. Chewing sticks (miswak) of Salvadora persica L. (Sp) are traditionally used as natural brush to ensure oral health in developing countries. Both Gt and Sp extracts were reported to have anti-bacterial activity against many dental plaque bacteria. However, their combination has never been tested to have anti-bacterial and anti-adherence effect against primary dental plaque colonizers, playing an initial role in the dental plaque development, which was investigated in this study. Two-fold serial micro-dilution method was used to measure minimal inhibitory concentration (MIC) of aqueous extracts of Gt, Sp and their combinations. Adsorption to hexadecane was used to determine the cell surface hydrophobicity (CSH) of bacterial cells. Glass beads were used to mimic the hard tissue surfaces, and were coated with saliva to develop experimental pellicles for the adhesion of the primary colonizing bacteria. Gt aqueous extracts exhibited better anti-plaque effect than Sp aqueous extracts. Their combination, equivalent to 1/4 and 1/2 of MIC values of Gt and Sp extracts respectively, showed synergistic anti-plaque properties with fractional inhibitory concentration (FIC) equal to 0.75. This combination was found to significantly reduce CSH (p<0.05) and lower the adherence ability (p<0.003) towards experimental pellicles. Combination between Gt and Sp aqueous extracts exhibited synergistic anti-plaque activity, and could be used as a useful active agent to produce oral health care products. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Thounaojam, Menaka C; Jadeja, Ravirajsinh N; Salunke, Sunita P; Devkar, Ranjitsinh V; Ramachandran, A V
2012-10-01
The present study evaluates efficacy of Sida rhomboidea.Roxb (SR) leaves extract in ameliorating experimental atherosclerosis using in vitro and in vivo experimental models. Atherogenic (ATH) diet fed rats recorded significant increment in the serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very LDL (VLDL), autoantibody against oxidized LDL (Ox-LDL), markers of LDL oxidation and decrement in high-density lipoprotein (HDL) along with increment in aortic TC and TG. The ex vivo LDL oxidation assay revealed an increased susceptibility of LDL isolated from ATH rats to undergo copper mediated oxidation. These set of changes were minimized by simultaneous co-supplementation of SR extract to ATH diet fed rats. Histopathology of aorta and immunolocalization studies recorded pronounced atheromatous plaque formation, vascular calcification, significant elastin derangements and higher expression of macrophage surface marker (F4/80), vascular cell adhesion molecule-1 (VCAM-1) and p-selectin in ATH rats. Whereas, ATH+SR rats depicted minimal evidence of atheromatous plaque formation, calcium deposition, distortion/defragmentation of elastin and accumulation of macrophages along with lowered expression of VCAM-1 and P-selectin compared to ATH rats. Further, monocyte to macrophage differentiation and in vitro foam cell formation were significantly attenuated in presence of SR extract. In conclusion, SR extract has the potency of controlling experimental atherosclerosis and can be used as promising herbal supplement in combating atherosclerosis.
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Brandenbusch, Christoph; Glonke, Sebastian; Collins, Jonathan; Hoffrogge, Raimund; Grunwald, Klaudia; Bühler, Bruno; Schmid, Andreas; Sadowski, Gabriele
2015-11-01
The formation of stable emulsions in biphasic biotransformations catalyzed by microbial cells turned out to be a major hurdle for industrial implementation. Recently, a cost-effective and efficient downstream processing approach, using supercritical carbon dioxide (scCO2 ) for both irreversible emulsion destabilization (enabling complete phase separation within minutes of emulsion treatment) and product purification via extraction has been proposed by Brandenbusch et al. (2010). One of the key factors for a further development and scale-up of the approach is the understanding of the mechanism underlying scCO2 -assisted phase separation. A systematic approach was applied within this work to investigate the various factors influencing phase separation during scCO2 treatment (that is pressure, exposure of the cells to CO2 , and changes of cell surface properties). It was shown that cell toxification and cell disrupture are not responsible for emulsion destabilization. Proteins from the aqueous phase partially adsorb to cells present at the aqueous-organic interface, causing hydrophobic cell surface characteristics, and thus contribute to emulsion stabilization. By investigating the change in cell-surface hydrophobicity of these cells during CO2 treatment, it was found that a combination of catastrophic phase inversion and desorption of proteins from the cell surface is responsible for irreversible scCO2 mediated phase separation. These findings are essential for the definition of process windows for scCO2 -assisted phase separation in biphasic whole-cell biocatalysis. © 2015 Wiley Periodicals, Inc.
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Bravo, Elena; Amrani, Souliman; Aziz, Mohammed; Harnafi, Hicham; Napolitano, Mariarosaria
2008-12-01
Macrophage lipid accumulation induced by low density lipoproteins (LDL) plays a pivotal role in atherosclerotic plaque development. Previous work showed that Ocimum basilicum extract, used as hypocholesterolemic agent by traditional medicine in Morocco, has hypolipidemic activity in rat acute hyperlipimidemia. This study investigated the effects of ethanolic extract of O. basilicum on lipid accumulation in human macrophages. As modification of LDL increase atherogenicity of the particles we evaluated the effects of the extract on LDL oxidation. The extract caused a dose-related increase of LDL-resistance to Cu(2+)-induced oxidation. Furthermore, at the dose of 60 microg/ml, significantly decreases the accumulation of macrophage lipid droplets induced by modified LDL evaluated as by red-oil staining. Cholesterol esterification and triacylglycerol synthesis in the cells were not affected. Macrophage treatment with 60 microg/ml, but not 20 microg/ml, of the extract reduced newly synthesized unesterified cholesterol by about 60% and decreased scavenger receptors activity by about 20-30%, evaluated by the internalization of cholesterol carried by [(3)H]CE-aggregated-LDL. The results suggest that O. basilicum ethanolic extract has the capability to reduce foam cell formation through the reduction of cholesterol synthesis and the modulation of the activity of surface scavenger receptors.
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Li, Hao; Tao, Leiming; Huang, Feihong; Sun, Qiang; Zhao, Xiaojuan; Han, Junbo; Shen, Yan; Wang, Mingkui
2017-11-08
Perovskite solar cells have been demonstrated as promising low-cost and highly efficient next-generation solar cells. Enhancing V OC by minimization the interfacial recombination kinetics can further improve device performance. In this work, we for the first time reported on surface passivation of perovskite layers with chemical modified graphene oxides, which act as efficient interlayer to reduce interfacial recombination and enhance hole extraction as well. Our modeling points out that the passivation effect mainly comes from the interaction between functional group (4-fluorophenyl) and under-coordinated Pb ions. The resulting perovskite solar cells achieved high efficient power conversion efficiency of 18.75% with enhanced high open circuit V OC of 1.11 V. Ultrafast spectroscopy, photovoltage/photocurrent transient decay, and electronic impedance spectroscopy characterizations reveal the effective passivation effect and the energy loss mechanism. This work sheds light on the importance of interfacial engineering on the surface of perovskite layers and provides possible ways to improve device efficiency.
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Zhang, Xinyuan; Li, Zhiqi; Liu, Chunyu; Guo, Jiaxin; Shen, Liang; Guo, Wenbin
2018-03-15
The charge transfer and separation are significantly affected by the electron properties of the interface between the electron-donor layer and the carrier-transporting layer in polymer solar cells (PSCs). In this study, we investigate the electron extraction mechanism of PSCs with a low temperature solution-processed ZnO/PEI as electron transport layer. The incorporation of PEI layer can decrease the work function of ZnO and reduce interfacial barrier, which facilitates electron extraction and suppresses bimolecular recombination, leading to a significant performance enhancement. Furthermore, PEI layer can induce phase separation and passivite inorganic surface trap states as well as shift the interfacial energy offset between metal oxide and organic materials. This work offers a simple and effective way to improve the charge transporting property of organic photovoltaic devices. Copyright © 2017 Elsevier Inc. All rights reserved.
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Hemoglobin binding and catalytic heme extraction by IsdB near iron transporter domains.
Bowden, Catherine F M; Verstraete, Meghan M; Eltis, Lindsay D; Murphy, Michael E P
2014-04-15
The Isd (iron-regulated surface determinant) system is a multiprotein transporter that allows bacterium Staphylococcus aureus to take up iron from hemoglobin (Hb) during human infection. In this system, IsdB is a cell wall-anchored surface protein that contains two near iron transporter (NEAT) domains, one of which binds heme. IsdB rapidly extracts heme from Hb and transfers it to IsdA for relay into the bacterial cell. Using a series of recombinant IsdB constructs that included at least one NEAT domain, we demonstrated that both domains are required to bind Hb with high affinity (KD = 0.42 ± 0.05 μM) and to extract heme from Hb. Moreover, IsdB extracted heme only from oxidized metHb, although it also bound oxyHb and the Hb-CO complex. In a reconstituted model of the biological heme relay pathway, IsdB catalyzed the transfer of heme from metHb to IsdA with a Km for metHb of 0.75 ± 0.07 μN and a kcat of 0.22 ± 0.01 s(-1). The latter is consistent with the transfer of heme from metHb to IsdB being the rate-limiting step. With both NEAT domains and the linker region present in a single contiguous polypeptide, high-affinity Hb binding was achieved, rapid heme uptake was observed, and multiple turnovers of heme extraction from metHb and transfer to IsdA were conducted, representing all known Hb-heme uptake functions of the full-length IsdB protein.
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Effects of cholesterol depletion on membrane nanostructure in MCF-7 cells by atomic force microscopy
NASA Astrophysics Data System (ADS)
Wang, Yuhua; Jiang, Ningcheng; Shi, Aisi; Zheng, Liqin; Yang, Hongqin; Xie, Shusen
2017-02-01
The cell membrane is composed of phospholipids, glycolipids, cholesterol and proteins that are dynamic and heterogeneous distributed in the bilayer structure and many researches have showed that the plasma membrane in eukaryotic cells contains microdomains termed "lipid raft" in which cholesterol, sphingolipids and specific membrane proteins are enriched. Cholesterol extraction induced lipid raft disruption is one of the most widely used methods for lipid raft research and MβCD is a type of solvent to extract the cholesterol from cell membranes. In this study, the effect of MβCD treatment on the membrane nanostructure in MCF-7 living cells was investigated by atomic force microscopy. Different concentrations of MβCD were selected to deplete cholesterol for 30 min and the viability of cells was tested by MTT assay to obtain the optimal concentration. Then the nanostructure of the cell membrane was detected. The results show that an appropriate concentration of MβCD can induce the alteration of cell membranes nanostructure and the roughness of membrane surface decreases significantly. This may indicate that microdomains of the cell membrane disappear and the cell membrane appears more smoothly. Cholesterol can affect nanostructure and inhomogeneity of the plasma membrane in living cells.
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NASA Astrophysics Data System (ADS)
Ma, Xia-Xia; Li, Ze-Sheng
2018-01-01
Oxygen molecule has a negative effect on perovskite solar cells, which has been investigated experimentally. However, detailed theoretical research is still rare. This study presents a microscopic view to reveal the interaction mechanism between O2 and perovskite based on the first-principles calculation. The results show that O2 is adsorbed on the (100) surface of MAPbI3 perovskite mainly by Van der Waals force. O2 adsorption makes the MAPbI3 surface generate a small number of positive charges, which leads to the increase of the work function of the MAPbI3 surface. This is in agreement with the experimental measurement. And increased work function of MAPbI3 surface is not beneficial to electron transfer from perovskite to electronic extraction layer (such as TiO2). Comparison of the density of states (DOS) of the clean (100) surface and the adsorbed system shows that an in-gap state belonging to O2 appears, which can explain the phenomenon observed from experiments that electron transfers from the surface of perovskite to O2 to form superoxide. The theoretical power conversion efficiency of the system with and without O2 adsorption is evaluated, and it turns out that the power conversion efficiency of the system with O2 adsorption is slightly lower than that of the system without O2 adsorption. This result indicates that avoiding the introduction of O2 molecules between perovskite and electronic extraction layer is beneficial to the perovskite solar cell.
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Arjomandzadegan, Mohammad; Emami, Navid; Habibi, Ghasem; Farazi, Ali Asghar; Kahbazi, Manijeh; Sarmadian, Hossein; Jabbari, Mansooreh; Hosseini, Hossein; Ramezani, Mona
2016-12-01
Resistances to herbal medicines are still not defined and finding natural remedies against drug resistant Mycobacterium tuberculosis (MTB) has research priority. The antimycobacterial susceptibility method for herbal extracts is unclearly defined and there is no standard method for assessment of the materials against bacteria. In the present study, time kill of three medicinal plants was determined against MTB. The clinical isolate of MTB from a patient who harbored confirmed tuberculosis was used in the study. Aqueous extracts of Aloe vera leaves, mint, and Hypericum perforatum were prepared using reflux distillation. Disk diffusion methods were conducted in Petri dishes and McCartney bottles containing Löwenstein-Jensen medium to measure the sensitivity of plant extracts in serial concentrations of 0.25-8mg/mL. A pour plate method was performed by mixing 0.7mL of each concentration of extract in 5mL Löwenstein-Jensen medium followed by surface culturing of MTB fresh cells. The time kill method was conducted by bacterial suspension in equal amounts of the extract and viable evaluation in fresh culture at the beginning, and at 24-h, 48-h, 72-h, and 1-week intervals. All cultures were incubated at 37°C for 4weeks. Inoculum concentrations were considered as a variable. The zones of inhibition of A. vera, H. perforatum, and mint extracts in the disk diffusion method in McCartney bottles were 60mm, 41mm, and zero, respectively, but Petri dishes did not have repeatable results. In the pour plate method, an extract concentration up to 1mg/mL could inhibit cell growth. In mint extract, colony forming was four times more than the others at 0.5mg/mL. Time kill of 95% of cells occurred when exposed to extracts of A. vera and H. perforatum separately, but was 50% in 24 h and 20% in 10 min. The time kill for mint was 95% in 1week. The results give some scientific basis to the use of plant extracts for growth control of MTB cells. Clinical trials are recommended for assessment of the extract as complementary medicine, as well as for antisepsis. Copyright © 2016.
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Whitehead, Kathryn A; Smith, Lindsay A; Verran, Joanna
2008-09-30
Open food contact surfaces were subjected to organic soiling to provide a source for transfer of microbial cells. Rapid industrial methods used for the detection of residual cells and soil e.g. ATP (adenosine triphosphate) bioluminescence and an ultraviolet (UV) light detection method were assessed for their ability to detect organic soils, or organic soil-cell mix on surfaces. A range of soils (complex [meat extract, fish extract, cottage cheese extract]; oils [cholesterol, fish oil, mixed fatty acids]; proteins [bovine serum albumin, fish peptones casein]; carbohydrates [glycogen, starch, lactose]); was used. Under UV, oily soils, mixed fatty acids, cholesterol and casein were detected at low concentrations, with detection levels ranging from 1% to 0.001% for different substances. Glycogen was the most difficult substance to detect at lower concentrations. Using UV wavelength bands (lambda) of 330-380 nm, 510-560 nm and 590-650 nm, wavelength bands of 330-380 nm, illuminated most of the soils well, whilst the wavelength band of 510-560 nm illuminated the fish extract, cholesterol and fatty acids; the 590-650 nm wavelength band illuminated the lactose. Soils at all concentrations were detected by the ATP bioluminescence method; the complex soils gave the highest readings. When complex soils were combined with Listeria monocytogenes Scott A or a non-pathogenic Escherichia coli O157:H7, ATP measurements increased by 1-2 logs. For UV illumination, the L. monocytogenes and cheese combination was the most intensely illuminated, with E. coli and meat the least. UV illumination is a simple well established method for detecting food soil, with little change in findings when microorganisms are included. Performance can be enhanced in certain circumstances by altering the wavelength. ATP bioluminescence is a proven system for hygienic assessment being especially useful in the presence of microorganisms rather than organic soil alone.
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Jaramillo, Isabel C.; Sturrock, Anne; Ghiassi, Hossein; Woller, Diana J.; Deering-Rice, Cassandra E.; Lighty, JoAnn S.; Paine, Robert; Reilly, Christopher; Kelly, Kerry E.
2017-01-01
The physicochemical properties of combustion particles that promote lung toxicity are not fully understood, hindered by the fact that combustion particles vary based on the fuel and combustion conditions. Real-world combustion-particle properties also continually change as new fuels are implemented, engines age, and engine technologies evolve. This work used laboratory-generated particles produced under controlled combustion conditions in an effort to understand the relationship between different particle properties and the activation of established toxicological outcomes in human lung cells (H441 and THP-1). Particles were generated from controlled combustion of two simple biofuel/diesel surrogates (methyl decanoate and dodecane/BD, and butanol and dodecane/AD) and compared to a widely studied reference diesel particle (NIST SRM2975/RD). BD, AD, and RD particles exhibited differences in size, surface area, extractable chemical mass, and the content of individual polycyclic aromatic hydrocarbons (PAHs). Some of these differences were directly associated with different effects on biological responses. BD particles had the greatest surface area, amount of extractable material and oxidizing potential. These particles and extracts induced cytochrome P450 1A1 and 1B1 enzyme mRNA in lung cells. AD particles and extracts had the greatest total PAH content and also caused CYP1A1 and 1B1 mRNA induction. The RD extract contained the highest relative concentration of 2-ring PAHs and stimulated the greatest level of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNFα) cytokine secretion. Finally, AD and RD were more potent activators of TRPA1 than BD, and while neither the TRPA1 antagonist HC-030031 nor the antioxidant N-acetylcysteine (NAC) affected CYP1A1 or 1B1 mRNA induction, both inhibitors reduced IL-8 secretion and mRNA induction. These results highlight that differences in fuel and combustion conditions affect the physicochemical properties of particles, and these differences, in turn, affect commonly studied biological/toxicological responses. PMID:29227181
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Ultrastructural effects of silicone oil on the clear crystalline lens of the human eye.
Soliman, Wael; Sharaf, Mohamed; Abdelazeem, Khaled; El-Gamal, Dalia; Nafady, Allam
2018-03-01
To evaluate light and electron microscopic changes of the anterior capsule and its epithelium after clear lens extraction of vitrectomized myopic eyes with silicone oil tamponade. This prospective, controlled, non-randomized, interventional study included 20 anterior lens capsular specimens that were excised during combined clear lens extraction and silicone oil removal from previously vitrectomized highly myopic patients with silicone oil tamponade for previous retinal detachment surgeries. The specimens were examined via light microscopy and electron microscopy and compared with 20 anterior capsule specimens removed during clear lens extraction of non-vitrectomized highly myopic eyes. Light microscopic examination of clear lens anterior capsule specimens of vitrectomized myopic eyes filled with silicone oil showed relatively more flat cells with irregular outline of lens' epithelial cells with wide intercellular spaces, deeply stained nuclei, and multiple intracytoplasmic vacuoles. Scanning electron microscopy revealed collagenous surfaces filled with multiple pits, depressions, and abnormal deposits. Transmission electron microscopy revealed lens epithelial cells with apoptotic changes, many cytoplasmic vacuoles, and filopodia-like protrusions between lens epithelial cells and the capsule. Epithelial proliferation and multilayering were also observed. silicone oil may play a role in the development of apoptotic and histopathological changes in clear lens epithelial cells. Clarity of the lens at the time of silicone oil removal does not indicate an absence of cataractous changes. We found justification of combined clear lens extraction and silicone oil removal or combined phacovitrectomy when silicone oil injection is planned, but further long-term studies with larger patient groups are required.
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Meniscus and beam halo formation in a tandem-type negative ion source with surface production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miyamoto, K.; Okuda, S.; Hatayama, A.
2012-06-04
A meniscus of plasma-beam boundary in H{sup -} ion sources largely affects the extracted H{sup -} ion beam optics. Although it is hypothesized that the shape of the meniscus is one of the main reasons for the beam halo observed in experiments, a physical mechanism of the beam halo formation is not yet fully understood. In this letter, it is first shown by the 2D particle in cell simulation that the H{sup -} ions extracted from the periphery of the meniscus cause a beam halo since the surface produced H{sup -} ions penetrate into the bulk plasma, and, thus, themore » resultant meniscus has a relatively large curvature.« less
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Quantitative Analysis of Filament Branch Orientation in Listeria Actin Comet Tails.
Jasnin, Marion; Crevenna, Alvaro H
2016-02-23
Several bacterial and viral pathogens hijack the host actin cytoskeleton machinery to facilitate spread and infection. In particular, Listeria uses Arp2/3-mediated actin filament nucleation at the bacterial surface to generate a branched network that will help propel the bacteria. However, the mechanism of force generation remains elusive due to the lack of high-resolution three-dimensional structural data on the spatial organization of the actin mother and daughter (i.e., branch) filaments within this network. Here, we have explored the three-dimensional structure of Listeria actin tails in Xenopus laevis egg extracts using cryo-electron tomography. We found that the architecture of Listeria actin tails is shared between those formed in cells and in cell extracts. Both contained nanoscopic bundles along the plane of the substrate, where the bacterium lies, and upright filaments (also called Z filaments), both oriented tangentially to the bacterial cell wall. Here, we were able to identify actin filament intersections, which likely correspond to branches, within the tails. A quantitative analysis of putative Arp2/3-mediated branches in the actin network showed that mother filaments lie on the plane of the substrate, whereas daughter filaments have random deviations out of this plane. Moreover, the analysis revealed that branches are randomly oriented with respect to the bacterial surface. Therefore, the actin filament network does not push directly toward the surface but rather accumulates, building up stress around the Listeria surface. Our results favor a mechanism of force generation for Listeria movement where the stress is released into propulsive motion. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.
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NASA Astrophysics Data System (ADS)
Sakota, Daisuke; Takatani, Setsuo
2012-04-01
To achieve the quantitative optical non-invasive diagnosis of blood during extracorporeal circulation therapies, the instrumental technique to extract extracellular spectra from whole blood was developed. In the circuit, the continuous blood flow was generated by a centrifugal blood pump. The oxygen saturation was maintained 100% by an oxygenator. The developed glass optical flow cell was attached to the outlet tubing of the oxygenator. The halogen lamp including the light from 400 to 900 nm wavelength was used for the light source. The light was guided into an optical fiber. The light emitted by the fiber was collimated and emitted to the flow cell flat surface at the incident angle of 45 degrees. The light just reflected on the boundary between inner surface of the flow cell and plasma at 45 degrees was detected by the detection fiber. The detected light was analyzed by a spectral photometer. The obtained spectrum from 400 to 600nm wavelength was not changed with respect to the hematocrit. In contrast, the signal in the spectral range was changed when the plasma free hemoglobin increased. By using two spectral range, 505+/-5 nm and 542.5+/-2.5 nm, the differential spectrum was correlated with the free hemoglobin at R2=0.99. On the other hand, as for the hematocrit, the differential spectrum was not correlated at R2=0.01. Finally, the plasma free hemoglobin was quantified with the accuracy of 22+/-19mg/dL. The result shows that the developed plasma surface reflectance spectroscopy (PSRS) can extract the plasma spectrum from flowing whole blood.
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Conventional and whitening toothpastes: cytotoxicity, genotoxicity and effect on the enamel surface.
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.
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Zapolska-Downar, D; Bryk, D; Małecki, M; Hajdukiewicz, K; Sitkiewicz, D
2012-08-01
Altered expression of cell adhesion molecules (CAMs) has been implicated in a variety of chronic inflammatory conditions, including atherosclerosis. Regulation of adhesion molecule expression by specific redox-sensitive mechanisms has been reported. Additionally, it has been observed that the extract of Aronia melanocarpa (A. Melanocarpa) fruits, rich in polyphenols, exhibits potent anti-oxidant properties and displays cardioprotective activity. Human aortic endothelial cells (HAECs) were pretreated with various concentrations (primarily 50 μg/mL) of Aronia Melanocarpa fruit extract prior to treatment with TNFα (10 ng/mL) for various periods of time. The surface protein and mRNA expression of ICAM-1 and VCAM-1 were determined using flow cytometry and real-time RT-PCR, respectively. Adhesion of peripheral blood mononuclear leucocytes (PBMLs) to TNFα-treated HAECs was evaluated by an adhesion assay. Activation of NF-κB was evaluated by measuring NF-κB p65 phosphorylation using flow cytometry. ROS production was determined by reduction in fluorescent 2',7'-dichlorofluorescein diacetate (DCFH-DA). Tested A. Melanocarpa extract significantly inhibited the expression of ICAM-1 and VCAM-1, attenuated the phosphorylation of NF-κB p65 and decreased intracellular ROS production in TNFα-treated HAECs. We conclude that A. Melanocarpa fruit extract exhibits anti-inflammatory effects in HAECs by inhibiting the expression of endothelial CAMs, activation of NF-κB and production of ROS.
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Improvement of Aluminum-Air Battery Performances by the Application of Flax Straw Extract.
Grishina, Ekaterina; Gelman, Danny; Belopukhov, Sergey; Starosvetsky, David; Groysman, Alec; Ein-Eli, Yair
2016-08-23
The effect of a flax straw extract on Al corrosion inhibition in a strong alkaline solution was studied by using electrochemical measurements, weight-loss analysis, SEM, and FTIR spectroscopy. Flax straw extract added (3 vol %) to the 5 m KOH solution to act as a mixed-type Al corrosion inhibitor. The electrochemistry of Al in the presence of a flax straw extract in the alkaline solution, the effect of the extract on the Al morphology and surface films formed, and the corrosion inhibition mechanism are discussed. Finally, the Al-air battery discharge capacity recorded from a cell that used the flax straw extract in the alkaline electrolyte is substantially higher than that with only a pure alkaline electrolyte. This improved sustainability of the Al anode is attributed to Al corrosion inhibition and, consequently, to hydrogen evolution suppression. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Optimization of acidic extraction of astaxanthin from Phaffia rhodozyma *
Ni, Hui; Chen, Qi-he; He, Guo-qing; Wu, Guang-bin; Yang, Yuan-fan
2008-01-01
Optimization of a process for extracting astaxanthin from Phaffia rhodozyma by acidic method was investigated, regarding several extraction factors such as acids, organic solvents, temperature and time. Fractional factorial design, central composite design and response surface methodology were used to derive a statistically optimal model, which corresponded to the following optimal condition: concentration of lactic acid at 5.55 mol/L, ratio of ethanol to yeast dry weight at 20.25 ml/g, temperature for cell-disruption at 30 °C, and extraction time for 3 min. Under this condition, astaxanthin and the total carotenoids could be extracted in amounts of 1294.7 μg/g and 1516.0 μg/g, respectively. This acidic method has advantages such as high extraction efficiency, low chemical toxicity and no special requirement of instruments. Therefore, it might be a more feasible and practical method for industrial practice. PMID:18196613
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Ruskoski, Sallie A; Champlin, Franklin R
2017-07-01
The purpose of the present study was to obtain a better understanding of the relationship between cell surface physiology and outer cellular envelope permeability for hydrophobic substances in mucoid and non-mucoid B. multivorans strains, as well as in two capsule-deficient derivatives of a mucoid parental strain. Cell surface hydrophobicity properties were determined using the hydrocarbon adherence method, while outer cell envelope accessibility and permeability for non-polar compounds were measured using hydrophobic antimicrobial agent susceptibility and fluorescent probe assays. Extracellular polysaccharide (EPS) production was assessed by cultivating strains of disparate origin on yeast extract agar (YEA) containing different sugars, while the resultant colonial and cellular morphological parameters were assessed macro- and microscopically, respectively.Results/Key findings. The cell surfaces of all the strains were hydrophilic, impermeable to mechanistically disparate hydrophobic antibacterial agents and inaccessible to the hydrophobic probe N-phenyl-1-napthylamine, regardless of EPS phenotype. Supplementation of basal YEA with eight different sugars enhanced macroscopic EPS expression for all but one non-mucoid strain, with mannose potentiating the greatest effect. Despite acquisition of the mucoid phenotype, non-mucoid strains remained non-capsulated and capsulation of a hyper-mucoid strain and its two non-mucoid derivative strains was unaffected, as judged by microscopic observation. These data support the conclusion that EPS expression and the consistent mucoid phenotype are not necessarily associated with the ability of the outer cell surface to associate with non-polar substances or cellular capsulation.
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Krasowska, Anna; Murzyn, Anna; Dyjankiewicz, Agnieszka; Łukaszewicz, Marcin; Dziadkowiec, Dorota
2009-12-01
The dimorphic fungus Candida albicans is a member of the normal flora residing in the intestinal tract of humans. In spite of this, under certain conditions it can induce both superficial and serious systemic diseases, as well as be the cause of gastrointestinal infections. Saccharomyces boulardii is a yeast strain that has been shown to have applications in the prevention and treatment of intestinal infections caused by bacterial pathogens. The purpose of this study was to determine whether S. boulardii affects the virulence factors of C. albicans. We demonstrate the inhibitory effect of live S. boulardii cells on the filamentation (hyphae and pseudohyphae formation) of C. albicans SC5314 strain proportional to the amount of S. boulardii added. An extract from S. boulardii culture has a similar effect. Live S. boulardii and the extract from S. boulardii culture filtrate diminish C. albicans adhesion to and subsequent biofilm formation on polystyrene surfaces under both aerobic and microaerophilic conditions. This effect is very strong and requires lower doses of S. boulardii cells or concentrations of the extract than serum-induced filamentation tests. Saccharomyces boulardii has a strong negative effect on very important virulence factors of C. albicans, i.e. the ability to form filaments and to adhere and form biofilms on plastic surfaces.
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Zhuang, Xinming; Feng, Xuechao
2018-01-01
Candida albicans is the most common fungal pathogen causing serious diseases, while there are only a paucity of antifungal drugs. Therefore, the present study was performed to investigate the antifungal effects of saponin extract from rhizomes of Dioscorea panthaica Prain et Burk (Huangshanyao Saponin extract, HSE) against C. albicans. HSE inhibits the planktonic growth and biofilm formation and development of C. albicans. 16–64 μg/mL of HSE could inhibit adhesion to polystyrene surfaces, transition from yeast to filamentous growth, and production of secreted phospholipase and could also induce endogenous reactive oxygen species (ROS) production and disrupt cell membrane in planktonic cells. Inhibitory activities against extracellular exopolysaccharide (EPS) production and ROS production in preformed biofilms could be inhibited by 64–256 μg/mL of HSE. Cytotoxicity against human Chang's liver cells is low, with a half maximal inhibitory concentration (IC50) of about 256 μg/mL. In sum, our study suggested that HSE might be used as a potential antifungal therapeutic against C. albicans. PMID:29853962
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Defined plant extracts can protect human cells against combined xenobiotic effects
2011-01-01
Background Pollutants representative of common environmental contaminants induce intracellular toxicity in human cells, which is generally amplified in combinations. We wanted to test the common pathways of intoxication and detoxification in human embryonic and liver cell lines. We used various pollutants such as Roundup residues, Bisphenol-A and Atrazine, and five precise medicinal plant extracts called Circ1, Dig1, Dig2, Sp1, and Uro1 in order to understand whether specific molecular actions took place or not. Methods Kidney and liver are major detoxification organs. We have studied embryonic kidney and hepatic human cell lines E293 and HepG2. The intoxication was induced on the one hand by a formulation of one of the most common herbicides worldwide, Roundup 450 GT+ (glyphosate and specific adjuvants), and on the other hand by a mixture of Bisphenol-A and Atrazine, all found in surface waters, feed and food. The prevention and curative effects of plant extracts were also measured on mitochondrial succinate dehydrogenase activity, on the entry of radiolabelled glyphosate (in Roundup) in cells, and on cytochromes P450 1A2 and 3A4 as well as glutathione-S-transferase. Results Clear toxicities of pollutants were observed on both cell lines at very low sub-agricultural dilutions. The prevention of such phenomena took place within 48 h with the plant extracts tested, with success rates ranging between 25-34% for the E293 intoxicated by Roundup, and surprisingly up to 71% for the HepG2. By contrast, after intoxication, no plant extract was capable of restoring E293 viability within 48 h, however, two medicinal plant combinations did restore the Bisphenol-A/Atrazine intoxicated HepG2 up to 24-28%. The analysis of underlying mechanisms revealed that plant extracts were not capable of preventing radiolabelled glyphosate from entering cells; however Dig2 did restore the CYP1A2 activity disrupted by Roundup, and had only a mild preventive effect on the CYP3A4, and no effect on the glutathione S-transferase. Conclusions Environmental pollutants have intracellular effects that can be prevented, or cured in part, by precise medicinal plant extracts in two human cell lines. This appears to be mediated at least in part by the cytochromes P450 modulation. PMID:21251308
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Sodeifian, Gholamhossein; Sajadian, Seyed Ali; Honarvar, Bizhan
2018-04-01
Extraction of oil from Dracocephalum kotschyi Boiss seeds using supercritical carbon dioxide was designed using central composite design to evaluate the effect of various operating parameters including pressure, temperature, particle size and extraction time on the oil yield. Maximum extraction yield predicted from response surface method was 71.53% under the process conditions with pressure of 220 bar, temperature of 35 °C, particle diameter of 0.61 mm and extraction time of 130 min. Furthermore, broken and intact cells model was utilised to consider mass transfer kinetics of extracted natural materials. The results revealed that the model had a good agreement with the experimental data. The oil samples obtained via supercritical and solvent extraction methods were analysed by gas chromatography. The most abundant acid was linolenic acid. The results analysis showed that there was no significant difference between the fatty acid contents of the oils obtained by the supercritical and solvent extraction techniques.
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Plastron Respiration Using Commercial Fabrics
Atherton, Shaun; Brennan, Joseph C.; Morris, Robert H.; Smith, Joshua D.E.; Hamlett, Christopher A.E.; McHale, Glen; Shirtcliffe, Neil J.; Newton, Michael I.
2014-01-01
A variety of insect and arachnid species are able to remain submerged in water indefinitely using plastron respiration. A plastron is a surface-retained film of air produced by surface morphology that acts as an oxygen-carbon dioxide exchange surface. Many highly water repellent and hydrophobic surfaces when placed in water exhibit a silvery sheen which is characteristic of a plastron. In this article, the hydrophobicity of a range of commercially available water repellent fabrics and polymer membranes is investigated, and how the surface of the materials mimics this mechanism of underwater respiration is demonstrated allowing direct extraction of oxygen from oxygenated water. The coverage of the surface with the plastron air layer was measured using confocal microscopy. A zinc/oxygen cell is used to consume oxygen within containers constructed from the different membranes, and the oxygen consumed by the cell is compared to the change in oxygen concentration as measured by an oxygen probe. By comparing the membranes to an air-tight reference sample, it was found that the membranes facilitated oxygen transfer from the water into the container, with the most successful membrane showing a 1.90:1 ratio between the cell oxygen consumption and the change in concentration within the container. PMID:28788469
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Efficient planar heterojunction perovskite solar cells employing graphene oxide as hole conductor.
Wu, Zhongwei; Bai, Sai; Xiang, Jian; Yuan, Zhongcheng; Yang, Yingguo; Cui, Wei; Gao, Xingyu; Liu, Zhuang; Jin, Yizheng; Sun, Baoquan
2014-09-21
Graphene oxide (GO) is employed as a hole conductor in inverted planar heterojunction perovskite solar cells, and the devices with CH₃NH₃PbI₃-xClx as absorber achieve an efficiency of over 12%. The perovskite film grown on GO exhibits enhanced crystallization, high surface coverage ratio as well as preferred in-plane orientation of the (110) plane. Efficient hole extraction from the perovskite to GO is demonstrated.
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Heinzelmann, Elsbeth
2016-01-01
At HES-SO Valais-Wallis, Prof. Fabian Fischer is specialized in microbial fuel cells for novel applications that meet the challenge of producing renewable energies. He and his team possess a unique expertise in bioelectric energy vector generation, phosphate extraction (CHIMIA 2015, 69, 296) and the testing of antimicrobial surfaces. Let's take a look behind the scenes of the Institute of Life Technologies in Sion.
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Gurunathan, Sangiliyandi; Han, JaeWoong; Park, Jung Hyun; Kim, Jin Hoi
2014-01-01
Background Recently, graphene and graphene-related materials have attracted much attention due their unique properties, such as their physical, chemical, and biocompatibility properties. This study aimed to determine the cytotoxic effects of graphene oxide (GO) that is reduced biologically using Ganoderma spp. mushroom extracts in MDA-MB-231 human breast cancer cells. Methods Herein, we describe a facile and green method for the reduction of GO using extracts of Ganoderma spp. as a reducing agent. GO was reduced without any hazardous chemicals in an aqueous solution, and the reduced GO was characterized using a range of analytical procedures. The Ganoderma extract (GE)-reduced GO (GE-rGO) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, dynamic light scattering, scanning electron microscopy, Raman spectroscopy, and atomic force microscopy. Furthermore, the toxicity of GE-rGO was evaluated using a sequence of assays such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation in human breast cancer cells (MDA-MB-231). Results The preliminary characterization of reduction of GO was confirmed by the red-shifting of the absorption peak for GE-rGO to 265 nm from 230 nm. The size of GO and GE-rGO was found to be 1,880 and 3,200 nm, respectively. X-ray diffraction results confirmed that reduction processes of GO and the processes of removing intercalated water molecules and the oxide groups. The surface functionalities and chemical natures of GO and GE-rGO were confirmed using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface morphologies of the synthesized graphene were analyzed using high-resolution scanning electron microscopy. Raman spectroscopy revealed single- and multilayer properties of GE-rGO. Atomic force microscopy images provided evidence for the formation of graphene. Furthermore, the effect of GO and GE-rGO was examined using a series of assays, such as cell viability, membrane integrity, and reactive oxygen species generation, which are key molecules involved in apoptosis. The results obtained from cell viability and lactate dehydrogenase assay suggest that GO and GE-rGO cause dose-dependent toxicity in the cells. Interestingly, it was found that biologically derived GE-rGO is more toxic to cancer cells than GO. Conclusion We describe a simple, green, nontoxic, and cost-effective approach to producing graphene using mushroom extract as a reducing and stabilizing agent. The proposed method could enable synthesis of graphene with potential biological and biomedical applications such as in cancer and angiogenic disorders. To our knowledge, this is the first report using mushroom extract as a reducing agent for the synthesis of graphene. Mushroom extract can be used as a biocatalyst for the production of graphene. PMID:24741313
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A Spectrum of Monoclonal Antibodies Reactive with Human Mammary Tumor Cells
NASA Astrophysics Data System (ADS)
Colcher, D.; Horan Hand, P.; Nuti, M.; Schlom, J.
1981-05-01
Splenic lymphocytes of mice, immunized with membrane-enriched fractions of metastatic human mammary carcinoma tissues, were fused with the NS-1 non-immunoglobulin-secreting murine myeloma cell line. This resulted in the generation of hybridoma cultures secreting immunoglobulins reactive in solid-phase radioimmunoassays with extracts of metastatic mammary carcinoma cells from involved livers, but not with extracts of apparently normal human liver. As a result of further screening of immunoglobulin reactivities and double cloning of cultures, 11 monoclonal antibodies were chosen that demonstrated reactivities with human mammary tumor cells and not with apparently normal human tissues. These monoclonal antibodies could be placed into at least five major groups on the basis of their differential binding to the surface of various live human mammary tumor cells in culture, to extracts of mammary tumor tissues, or to tissue sections of mammary tumor cells studied by the immunoperoxidase technique. Whereas a spectrum of reactivities to mammary tumors was observed with the 11 monoclonal antibodies, no reactivity was observed to apparently normal cells of the following human tissues: breast, lymph node, lung, skin, testis, kidney, thymus, bone marrow, spleen, uterus, thyroid, intestine, liver, bladder, tonsils, stomach, prostate, and salivary gland. Several of the antibodies also demonstrated a ``pancarcinoma'' reactivity, showing binding to selected non-breast carcinomas. None of the monoclonal antibodies showed binding to purified ferritin or carcinoembryonic antigen. Monoclonal antibodies of all five major groups, however, demonstrated binding to human metastatic mammary carcinoma cells both in axillary lymph nodes and at distal sites.
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Jeong, Ji Yeon; Liu, Qing; Kim, Seon Beom; Jo, Yang Hee; Mo, Eun Jin; Yang, Hyo Hee; Song, Dae Hye; Hwang, Bang Yeon; Lee, Mi Kyeong
2015-05-14
Melanin is a natural pigment that plays an important role in the protection of skin, however, hyperpigmentation cause by excessive levels of melatonin is associated with several problems. Therefore, melanogenesis inhibitory natural products have been developed by the cosmetic industry as skin medications. The leaves of Morus alba (Moraceae) have been reported to inhibit melanogenesis, therefore, characterization of the melanogenesis inhibitory constituents of M. alba leaves was attempted in this study. Twenty compounds including eight benzofurans, 10 flavonoids, one stilbenoid and one chalcone were isolated from M. alba leaves and these phenolic constituents were shown to significantly inhibit tyrosinase activity and melanin content in B6F10 melanoma cells. To maximize the melanogenesis inhibitory activity and active phenolic contents, optimized M. alba leave extraction conditions were predicted using response surface methodology as a methanol concentration of 85.2%; an extraction temperature of 53.2 °C and an extraction time of 2 h. The tyrosinase inhibition and total phenolic content under optimal conditions were found to be 74.8% inhibition and 24.8 μg GAE/mg extract, which were well-matched with the predicted values of 75.0% inhibition and 23.8 μg GAE/mg extract. These results shall provide useful information about melanogenesis inhibitory constituents and optimized extracts from M. alba leaves as cosmetic therapeutics to reduce skin hyperpigmentation.
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Zeng, Zhaoyan; Li, Xiangzhou; Zhang, Sheng; Huang, Dan
2017-01-01
Nano bamboo charcoal is being widely used as sustained release carrier for chemicals for its high specific surface area, sound biocompatibility, and nontoxicity; however, there have been no reports on nano bamboo charcoal as sustained release carrier for traditional Chinese medicine (TCM). To study the effect of nano bamboo charcoal in absorbing and sustained releasing Eucommia ulmoides extract (EUE) and to verify the in vitro anticancer effect of the sustained release liquid, so as to provide a theoretical basis for the development and utilization of nano bamboo charcoal as TCM sustained-release preparation. The adsorption capacity for the nano bamboo charcoal on EUE was measured by Langmuir model, and the release experiment was carried out under intestinal fluid condition. Characteristic changes for the nano bamboo charcoal nano-drug delivery system with and without adsorption of E. ulmoides were evaluated by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and specific surface area. In addition, the anticancer effect from this novel bamboo charcoal E. ulmoides delivery system was evaluated against a human colon cancer cell line (HCT116). It was found that nano bamboo charcoal exhibits good adsorption capacity (up to 462.96 mg/g at 37°C). The cumulative release rate for EUE from this nano bamboo charcoal delivery system was 70.67%, and specific surface area for the nano bamboo charcoal decreased from 820.32 m 2 /g to 443.80 m 2 /g after EUE was loaded. An in vitro anticancer study showed that the inhibition rate for E. ulmoides against HCT116 cancer cells was 23.07%, for this novel bamboo charcoal nano-drug delivery system. This study provides a novel strategy for the delivery of traditional Chinese medicine using bamboo charcoal nano-drug delivery system. The adsorption equilibrium was reached after 30 min of ultrasonic treatmentThe saturated adsorption capacity of Eucommia ulmoides extract by nano bamboo charcoal under ultrosonic condition was 462. 96 mg/gThe cumulative release rate of E. ulmoides extract from the nano bamboo charcoal delivery system in artificial intestinal juice was 70.67%The inhibition ratio of HCT116 cancer cells by sustained release liquid was 23.07%. Abbreviation used: EUE: Eucommia ulmoides extract.
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Response of Human Skin Equivalents to Sarcoptes scabiei
MORGAN, MARJORIE S.; ARLIAN, LARRY G.
2010-01-01
Studies have shown that molecules in an extract made from bodies of the ectoparasitic mite, Sarcoptes scabiei De Geer, modulate cytokine secretion from cultured human keratinocytes and fibroblasts. In vivo, in the parasitized skin, these cells interact with each other by contact and cytokine mediators and with the matrix in which they reside. Therefore, these cell types may function differently together than they do separately. In this study, we used a human skin equivalent (HSE) model to investigate the influence of cellular interactions between keratinocytes and fibroblasts when the cells were exposed to active/burrowing scabies mites, mite products, and mite extracts. The HSE consisted of an epidermis of stratified stratum corneum, living keratinocytes, and basal cells above a dermis of fibroblasts in a collagen matrix. HSEs were inoculated on the surface or in the culture medium, and their cytokine secretions on the skin surface and into the culture medium were determined by enzyme-linked immunosorbent assay. Active mites on the surface of the HSE induced secretion of cutaneous T cell-attracting chemokine, thymic stromal lymphopoietin, interleukin (IL)-1α, IL-1β, IL-1 receptor antagonist (IL-1ra), IL-6, IL-8, monocyte chemoattractant protein-1, granulocyte/macrophage colony-stimulating factor, and macrophage colony-stimulating factor. The main difference between HSEs and monocultured cells was that the HSEs produced the proinflammatory cytokines IL-1α and IL-1β and their competitive inhibitor IL-1ra, whereas very little of these mediators was previously found for cultured keratinocytes and fibroblasts. It is not clear how the balance between these cytokines influences the overall host response. However, IL-1ra may contribute to the depression of an early cutaneous inflammatory response to scabies in humans. These contrasting results illustrate that cell interactions are important in the host’s response to burrowing scabies mites. PMID:20939384
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Tan, Li-Hong; Zhang, Dan; Yu, Bao; Zhao, Sheng-Ping; Wang, Jian-Wei; Yao, Ling; Cao, Wei-Guo
2015-11-01
Polysaccharide extraction from Dipsacus asperoides roots (DAP) was proved to possess strong antioxidant activities, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-Azobis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging activities, inhibiting β-carotene bleaching and strong reducing power. Cell assay demonstrated that the crude DAP possessed antioxidant activity and were effective against H2O2-induced L02 cells injury. Then, response surface methodology (RSM) was applied to optimize the ultrasonic extraction of DAP. The optimum variables given by central composite design (CCD) were as follows: ratio of water to raw material, 38.61mL/g; ultrasonic power, 308.68W; extraction time, 38.61min; and extraction temperature, 89°C. Under these conditions, the maximum yield of DAP obtained was 7.12±0.45%. Moreover, high performance liquid chromatography (HPLC) analysis suggested that the monosaccharide compositions of DAP contained primarily mannose, ribose, glucose, galactose, xylose and arabinose, with a molar ratio of 0.22:0.48:2.29:0.34:1.39:1.41. The results of the present study showed that DAP could be considered as potential sources of natural antioxidants. Copyright © 2015 Elsevier B.V. All rights reserved.
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Trans-Membrane Area Asymmetry Controls the Shape of Cellular Organelles
Beznoussenko, Galina V.; Pilyugin, Sergei S.; Geerts, Willie J. C.; Kozlov, Michael M.; Burger, Koert N. J.; Luini, Alberto; Derganc, Jure; Mironov, Alexander A.
2015-01-01
Membrane organelles often have complicated shapes and differ in their volume, surface area and membrane curvature. The ratio between the surface area of the cytosolic and luminal leaflets (trans-membrane area asymmetry (TAA)) determines the membrane curvature within different sites of the organelle. Thus, the shape of the organelle could be critically dependent on TAA. Here, using mathematical modeling and stereological measurements of TAA during fast transformation of organelle shapes, we present evidence that suggests that when organelle volume and surface area are constant, TAA can regulate transformation of the shape of the Golgi apparatus, endosomal multivesicular bodies, and microvilli of brush borders of kidney epithelial cells. Extraction of membrane curvature by small spheres, such as COPI-dependent vesicles within the Golgi (extraction of positive curvature), or by intraluminal vesicles within endosomes (extraction of negative curvature) controls the shape of these organelles. For instance, Golgi tubulation is critically dependent on the fusion of COPI vesicles with Golgi cisternae, and vice versa, for the extraction of membrane curvature into 50–60 nm vesicles, to induce transformation of Golgi tubules into cisternae. Also, formation of intraluminal ultra-small vesicles after fusion of endosomes allows equilibration of their TAA, volume and surface area. Finally, when microvilli of the brush border are broken into vesicles and microvilli fragments, TAA of these membranes remains the same as TAA of the microvilli. Thus, TAA has a significant role in transformation of organelle shape when other factors remain constant. PMID:25761238
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Xenopus extract approaches to studying microtubule organization and signaling in cytokinesis
Field, Christine M.; Pelletier, James F.; Mitchison, Timothy J.
2017-01-01
We report optimized methods for preparing actin-intact Xenopus egg extract. This extract is minimally perturbed, undiluted egg cytoplasm where the cell cycle can be experimentally controlled. It contains abundant organelles and glycogen, and supports active metabolism and cytoskeletal dynamics that closely mimic egg physiology. The concentration of the most abundant ~11,000 proteins is known from mass spectrometry. Actin-intact egg extract can be used for analysis of actin dynamics and interaction of actin with other cytoplasmic systems, as well as microtubule organization. It can be spread as thin layers, and naturally depletes oxygen though mitochondrial metabolism, which makes it ideal for fluorescence imaging. When combined with artificial lipid bilayers, it allows reconstitution and analysis of the spatially controlled signaling that positions the cleavage furrow during early cytokinesis. Actin-intact extract is generally useful for probing the biochemistry and biophysics of the large Xenopus egg. Protocols are provided for preparation of actin-intact egg extract, control of the cell cycle, fluorescent probes for cytoskeleton and cytoskeleton-dependent signaling, preparation of glass surfaces for imaging experiments, and immunodepletion to probe the role of specific proteins and protein complexes. We also describe methods for adding supported lipid bilayers to mimic the plasma membrane and for confining in microfluidic droplets to explore size scaling issues. PMID:28065319
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Worm, Margitta; Ernst, Dennis; Kraller, Markus; Babina, Magda
2017-01-01
The clinical efficacy and safety of allergoid immunotherapy have been demonstrated in clinical trials. However, simultaneous monitoring of the immunological changes by allergoids versus allergens in the cells of the same individual has not been extensively performed, and the impact of concurrent Toll-like receptor 4 (TLR4) ligation has not been specified. Three types of birch allergen were utilized: glutaraldehyde-treated allergoid (extract A), the same allergoid plus monophosphoryl lipid A (MPL), i.e., TLR4 ligand (extract A*), and native allergen (extract B). Antigen-specific responses after the in vitro stimulation of blood cells with the extracts were assessed by studying costimulatory receptors on the B cell surface by flow cytometry, cytokine responses by ELISA, and CD63 and CD203c upregulation (basophil activation test) in allergic versus nonallergic subjects. HLA-DR selectively increased upon allergen or allergoid treatment in the allergic group only. The extract types elicited similar cytokine responses, with IL-6 and IL-10 production detected only in certain atopic subjects. The allergoids revealed a strong reduction (100- to <10,000-fold) in basophil activation versus native allergen. Reactivity was undetectable in the basophils from nonallergic subjects. The allergenicity of the allergoid employed was sharply reduced when compared to the native allergen, while its immunogenicity was largely retained, especially in the presence of MPL. We also provide further evidence that allergic and nonallergic individuals show preexisting differences in their immune repertoires. © 2017 S. Karger AG, Basel.
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Mohsenipour, Zeinab; Hassanshahian, Mehdi
2015-08-01
Garlic is considered a rich source of many compounds, which shows antimicrobial effects. The ability of microorganisms to adhere to both biotic and abiotic surfaces and to form biofilm is responsible for a number of diseases of chronic nature, demonstrating extremely high resistance to antibiotics. Bacterial biofilms are complex communities of sessile microorganisms, embedded in an extracellular matrix and irreversibly attached to various surfaces. The present study evaluated the antimicrobial activity of Allium sativum extract against the biofilms of six pathogenic bacteria and their free-living forms. The clinical isolates in this study had not been studied in any other studies, especially in regard to biofilm disruption and inhibition of biofilm cell metabolic activity. Antimicrobial activities of A. sativum L. extracts (methanol and ethanol extracts) against planktonic forms of bacteria were determined using the disc diffusion method. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values were evaluated by a macrobroth dilution technique. The anti-biofilm effects were assessed by microtiter plate method. The results showed that the A. sativum L. extract discs did not have any zone of inhibition for the tested bacteria. However, The MIC values of A. sativum L. extracts (0.078 - 2.5 mg/mL) confirmed the high ability of these extracts for inhibition of planktonic bacteria. A. sativum L. extracts were efficient to inhibit biofilm structures and the concentration of each extract had a direct relation with the inhibitory effect. Finally, it can be suggested that the extracts of this plant be applied as antimicrobial agents against these pathogens, particularly in biofilm forms.
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Almeida, Catia Amancio; de Campos-Takaki, Galba Maria; Portela, Maristela Barbosa; Travassos, Luiz R; Alviano, Celuta Sales; Alviano, Daniela Sales
2013-10-01
The possible role of sialic acids in host cells-fungi interaction and their association with glycoproteins were evaluated using a clinical isolate of the dimorphic fungus Mucor polymorphosporus. Lectin-binding assays with spores and yeast cells denoted the presence of surface sialoglycoconjugates containing 2,3- and 2,6-linked sialylglycosyl groups. Western blotting with peroxidase-labeled Limulus polyphemus agglutinin revealed the occurrence of different sialoglycoprotein types in both cell lysates and cell wall protein extracts of mycelia, spores, and yeasts of M. polymorphosporus. Sialic acids contributed to the surface negative charge of spores and yeast forms as evaluated by adherence to a cationic substrate. Sialidase-treated spores were less resistant to phagocytosis by human neutrophils and monocytes from healthy individuals than control (untreated) fungal suspensions. The results suggest that sialic acids are terminal units of various glycoproteins of M. polymorphosporus, contributing to negative charge of yeasts and spore cells and protecting infectious propagules from destruction by host cells.
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McIlhinney, R A; Molnár, E
1996-04-01
To identify the location of the first transmembrane segment of the GluR1 glutamate receptor subunit artificial stop codons have been introduced into the N-terminal domain at amino acid positions 442, 510, and 563, namely just before and spanning the proposed first two transmembrane regions. The resultant truncated N-terminal fragments of GluR1, termed NT1, NT2, and NT3 respectively were expressed in Cos-7 cells and their cellular distribution and cell-surface expression analysed using an N-terminal antibody to GluR1. All of the fragments were fully glycosylated and were found to be associated with cell membranes but none was secreted. Differential extraction of the cell membranes indicated that both NT1 and NT2 behave as peripheral membrane proteins. In contrast NT3, like the full subunit, has integral membrane protein properties. Furthermore only NT3 is expressed at the cell surface as determined by immunofluorescence and cell-surface biotinylation. Protease protection assays indicated that only NT3 had a cytoplasmic tail. Binding studies using the selective ligand [(3)H]alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate ([(3)H]AMPA) demonstrated that NT3 does not bind ligand. Together these results indicate that the first transmembrane domain of the GluR1 subunit lies between residues 509 and 562, that the N-terminal domain alone cannot form a functional ligand-binding site and that this domain can be targeted to the cell surface provided that it has a transmembrane-spanning region.
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Wise, Jillian F; Berkova, Zuzana; Mathur, Rohit; Zhu, Haifeng; Braun, Frank K; Tao, Rong-Hua; Sabichi, Anita L; Ao, Xue; Maeng, Hoyoung; Samaniego, Felipe
2013-06-06
Resistance to Fas-mediated apoptosis is associated with poor cancer outcomes and chemoresistance. To elucidate potential mechanisms of defective Fas signaling, we screened primary lymphoma cell extracts for Fas-associated proteins that would have the potential to regulate Fas signaling. An activation-resistant Fas complex selectively included nucleolin. We confirmed the presence of nucleolin-Fas complexes in B-cell lymphoma cells and primary tissues, and the absence of such complexes in B-lymphocytes from healthy donors. RNA-binding domain 4 and the glycine/arginine-rich domain of nucleolin were essential for its association with Fas. Nucleolin colocalized with Fas on the surface of B-cell lymphoma cells. Nucleolin knockdown sensitized BJAB cells to Fas ligand (FasL)-induced and Fas agonistic antibody-induced apoptosis through enhanced binding, suggesting that nucleolin blocks the FasL-Fas interaction. Mice transfected with nucleolin were protected from the lethal effects of agonistic anti-mouse Fas antibody (Jo2) and had lower rates of hepatocyte apoptosis, compared with vector and a non-Fas-binding mutant of nucleolin. Our results show that cell surface nucleolin binds Fas, inhibits ligand binding, and thus prevents induction of Fas-mediated apoptosis in B-cell lymphomas and may serve as a new therapeutic target.
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Wise, Jillian F.; Berkova, Zuzana; Mathur, Rohit; Zhu, Haifeng; Braun, Frank K.; Tao, Rong-Hua; Sabichi, Anita L.; Ao, Xue; Maeng, Hoyoung
2013-01-01
Resistance to Fas-mediated apoptosis is associated with poor cancer outcomes and chemoresistance. To elucidate potential mechanisms of defective Fas signaling, we screened primary lymphoma cell extracts for Fas-associated proteins that would have the potential to regulate Fas signaling. An activation-resistant Fas complex selectively included nucleolin. We confirmed the presence of nucleolin-Fas complexes in B-cell lymphoma cells and primary tissues, and the absence of such complexes in B-lymphocytes from healthy donors. RNA-binding domain 4 and the glycine/arginine-rich domain of nucleolin were essential for its association with Fas. Nucleolin colocalized with Fas on the surface of B-cell lymphoma cells. Nucleolin knockdown sensitized BJAB cells to Fas ligand (FasL)-induced and Fas agonistic antibody-induced apoptosis through enhanced binding, suggesting that nucleolin blocks the FasL–Fas interaction. Mice transfected with nucleolin were protected from the lethal effects of agonistic anti-mouse Fas antibody (Jo2) and had lower rates of hepatocyte apoptosis, compared with vector and a non-Fas-binding mutant of nucleolin. Our results show that cell surface nucleolin binds Fas, inhibits ligand binding, and thus prevents induction of Fas-mediated apoptosis in B-cell lymphomas and may serve as a new therapeutic target. PMID:23599269
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Bashi, Davoud Salar; Dowom, Samaneh Attaran; Bazzaz, Bibi Sedigheh Fazly; Khanzadeh, Farhad; Soheili, Vahid; Mohammadpour, Ali
2016-05-01
To optimize the extraction method using response surface methodology, extract the phenolic compounds, and identify the antioxidant and biological properties of Stachys parviflora L. extracts. Maceration and ultrasound-assisted extraction (UAE) (4, 7, 10 min treatment time, 40, 70, 100 % high-intensity and 60, 80, 100 % (v v-1) methanol purity) were applied to obtain the extracts. SEM was conducted to provide the microstructure of the extracted plant. MICs (colorimetric assay), MFCs (colony diameter), total phenolic content, total flavonoid content, radical scavenging capacity and extraction efficiency were determined. HPLC analysis was applied to measure the existent phenolic compounds. A quadratic model (4 min treatment time, 74.5 % high-intensity and 74.2 % solvent purity) was suggested as the best (TPC: 20.89 mg GAE g-1 d.m., TFC: 6.22 mg QEs g-1 d.m., DPPH IC50: 21.86 µg ml-1 and EE: 113.65 mg g-1 d.m.) UAE extraction model. The optimized UAE extract was generally more effective against Gram-positive microorganisms (MIC: 10-20; MBC: 10-40 (mg ml-1)) than Gram-negative ones (MIC: 40; MBC: >40 (mg ml-1)). Moreover, it (MGI: 2.32-100 %) revealed more anti-mold activity than maceration (MGI: <28.77 %). Explosive disruption of the cell walls, therefore, enhanced extraction yield by acoustic cavitation, was elucidated using SEM. Caffeic acid, tannic acid, quercetin, trans ferulic acid and rosmarinic acid were determined as the phenolic compounds in the optimized extract. RSM optimization was successfully applied for UAE from S. parviflora. The considerable antioxidant and biological properties were attributed to the phenolic compounds.
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Bashi, Davoud Salar; Dowom, Samaneh Attaran; Bazzaz, Bibi Sedigheh Fazly; Khanzadeh, Farhad; Soheili, Vahid; Mohammadpour, Ali
2016-01-01
Objective(s): To optimize the extraction method using response surface methodology, extract the phenolic compounds, and identify the antioxidant and biological properties of Stachys parviflora L. extracts. Materials and Methods: Maceration and ultrasound-assisted extraction (UAE) (4, 7, 10 min treatment time, 40, 70, 100 % high-intensity and 60, 80, 100 % (v v-1) methanol purity) were applied to obtain the extracts. SEM was conducted to provide the microstructure of the extracted plant. MICs (colorimetric assay), MFCs (colony diameter), total phenolic content, total flavonoid content, radical scavenging capacity and extraction efficiency were determined. HPLC analysis was applied to measure the existent phenolic compounds. Results: A quadratic model (4 min treatment time, 74.5 % high-intensity and 74.2 % solvent purity) was suggested as the best (TPC: 20.89 mg GAE g-1 d.m., TFC: 6.22 mg QEs g-1 d.m., DPPH IC50: 21.86 µg ml-1 and EE: 113.65 mg g-1 d.m.) UAE extraction model. The optimized UAE extract was generally more effective against Gram-positive microorganisms (MIC: 10-20; MBC: 10-40 (mg ml-1)) than Gram-negative ones (MIC: 40; MBC: >40 (mg ml-1)). Moreover, it (MGI: 2.32-100 %) revealed more anti-mold activity than maceration (MGI: <28.77 %). Explosive disruption of the cell walls, therefore, enhanced extraction yield by acoustic cavitation, was elucidated using SEM. Caffeic acid, tannic acid, quercetin, trans ferulic acid and rosmarinic acid were determined as the phenolic compounds in the optimized extract. Conclusion: RSM optimization was successfully applied for UAE from S. parviflora. The considerable antioxidant and biological properties were attributed to the phenolic compounds. PMID:27403260
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Carbon-Based Nanomaterials in Biomass-Based Fuel-Fed Fuel Cells
Vestergaard, Mun’delanji C.; Tamiya, Eiichi
2017-01-01
Environmental and sustainable economical concerns are generating a growing interest in biofuels predominantly produced from biomass. It would be ideal if an energy conversion device could directly extract energy from a sustainable energy resource such as biomass. Unfortunately, up to now, such a direct conversion device produces insufficient power to meet the demand of practical applications. To realize the future of biofuel-fed fuel cells as a green energy conversion device, efforts have been devoted to the development of carbon-based nanomaterials with tunable electronic and surface characteristics to act as efficient metal-free electrocatalysts and/or as supporting matrix for metal-based electrocatalysts. We present here a mini review on the recent advances in carbon-based catalysts for each type of biofuel-fed/biofuel cells that directly/indirectly extract energy from biomass resources, and discuss the challenges and perspectives in this developing field. PMID:29125564
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Carbon-Based Nanomaterials in Biomass-Based Fuel-Fed Fuel Cells.
Hoa, Le Quynh; Vestergaard, Mun'delanji C; Tamiya, Eiichi
2017-11-10
Environmental and sustainable economical concerns are generating a growing interest in biofuels predominantly produced from biomass. It would be ideal if an energy conversion device could directly extract energy from a sustainable energy resource such as biomass. Unfortunately, up to now, such a direct conversion device produces insufficient power to meet the demand of practical applications. To realize the future of biofuel-fed fuel cells as a green energy conversion device, efforts have been devoted to the development of carbon-based nanomaterials with tunable electronic and surface characteristics to act as efficient metal-free electrocatalysts and/or as supporting matrix for metal-based electrocatalysts. We present here a mini review on the recent advances in carbon-based catalysts for each type of biofuel-fed/biofuel cells that directly/indirectly extract energy from biomass resources, and discuss the challenges and perspectives in this developing field.
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Adam, Fanny; Abert-Vian, Maryline; Peltier, Gilles; Chemat, Farid
2012-06-01
In order to comply with criteria of green chemistry concepts and sustainability, a new procedure has been performed for solvent-free ultrasound-assisted extraction (UAE) to extract lipids from fresh Nannochloropsis oculata biomass. Through response surface methodology (RSM) parameters affecting the oil recovery were optimized. Optimum conditions for oil extraction were estimated as follows: (i) 1000 W ultrasonic power, (ii) 30 min extraction time and (iii) biomass dry weight content at 5%. Yields were calculated by the total fatty acids methyl esters amounts analyzed by GC-FID-MS. The maximum oil recovery was around 0.21%. This value was compared with the one obtained with the conventional extraction method (Bligh and Dyer). Furthermore, effect of temperature on the yield was also investigated. The overall results show an innovative and effective extraction method adapted for microalgae oil recovery, without using solvent and with an enable scaling up. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Mandal, Debasis; Kumar Dash, Sandeep; Das, Balaram; Chattopadhyay, Sourav; Ghosh, Totan; Das, Debasis; Roy, Somenath
2016-10-01
Recently bio-inspired experimental processes for synthesis of nanoparticles are receiving significant attention in nanobiotechnology. Silver nanoparticles (Ag NPs) have been used very frequently in recent times to the wounds, burns and bacterial infections caused by drug-resistant microorganisms. Though, the antibacterial effects of Ag NPs on some multi drug-resistant bacteria specially against Gram positive bacteria has been established, but further investigation is needed to elicit its effectiveness against Gram negatives and to identify the probable mechanism of action. Thus, the present study was conducted to synthesize Ag NPs using Andrographis paniculata leaf extract and to investigate its antibacterial efficacy. After synthesis process the biosynthesized nanoparticles were purified and characterized with the help of various physical measurement techniques which raveled their purity, stability and small size range. The antimicrobial activity of Ag NPs was determined against both Gram-positive Enterococcus faecalis and Gram-negative Proteus vulgaris. Results showed comparatively higher antibacterial efficacy of Ag NPs against Gram positive Enterococcus faecalis strains. It was found that greater difference in zeta potential values between Gram positive bacteria and Ag NPs triggers better internalization of the particles. Thus the cell surface charge played vital role in cell killing which was confirmed by surface zeta potential study. Finally it may be concluded that green synthesized Ag NPs using Andrographis paniculata leaf extract can be very useful against both multi drug resistant Gram-positive and Gram-negative bacteria. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
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NASA Astrophysics Data System (ADS)
Kim, Hyo-Joong; Ko, Eun-Hye; Noh, Yong-Jin; Na, Seok-In; Kim, Han-Ki
2016-09-01
Nano-scale surface roughness in transparent ITO films was artificially formed by sputtering a mixed Ag and ITO layer and wet etching of segregated Ag nanoparticles from the surface of the ITO film. Effective removal of self-segregated Ag particles from the grain boundaries and surface of the crystalline ITO film led to a change in only the nano-scale surface morphology of ITO film without changes in the sheet resistance and optical transmittance. A nano-scale rough surface of the ITO film led to an increase in contact area between the hole transport layer and the ITO anode, and eventually increased the hole extraction efficiency in the organic solar cells (OSCs). The heterojunction OSCs fabricated on the ITO anode with a nano-scale surface roughness exhibited a higher power conversion efficiency of 3.320%, than that (2.938%) of OSCs made with the reference ITO/glass. The results here introduce a new method to improve the performance of OSCs by simply modifying the surface morphology of the ITO anodes.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yamashita, G.; Nagai, M., E-mail: mnagai@mp.es.osaka-u.ac.jp, E-mail: ashida@mp.es.osaka-u.ac.jp; Ashida, M., E-mail: mnagai@mp.es.osaka-u.ac.jp, E-mail: ashida@mp.es.osaka-u.ac.jp
We estimated the carrier multiplication efficiency in the most common solar-cell material, Si, by using optical-pump/terahertz-probe spectroscopy. Through close analysis of time-resolved data, we extracted the exact number of photoexcited carriers from the sheet carrier density 10 ps after photoexcitation, excluding the influences of spatial diffusion and surface recombination in the time domain. For incident photon energies greater than 4.0 eV, we observed enhanced internal quantum efficiency due to carrier multiplication. The evaluated value of internal quantum efficiency agrees well with the results of photocurrent measurements. This optical method allows us to estimate the carrier multiplication and surface recombination of carriersmore » quantitatively, which are crucial for the design of the solar cells.« less
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A Quartz Crystal Microbalance Immunosensor for Stem Cell Selection and Extraction
Costanzo, Salvatore; Zambrano, Gerardo; Mauro, Marco; Battaglia, Raffaele; Ferrini, Gianluca; Nastri, Flavia; Pavone, Vincenzo
2017-01-01
A cost-effective immunosensor for the detection and isolation of dental pulp stem cells (DPSCs) based on a quartz crystal microbalance (QCM) has been developed. The recognition mechanism relies on anti-CD34 antibodies, DPSC-specific monoclonal antibodies that are anchored on the surface of the quartz crystals. Due to its high specificity, real time detection, and low cost, the proposed technology has a promising potential in the field of cell biology, for the simultaneous detection and sorting of stem cells from heterogeneous cell samples. The QCM surface was properly tailored through a biotinylated self-assembled monolayer (SAM). The biotin–avidin interaction was used to immobilize the biotinylated anti-CD34 antibody on the gold-coated quartz crystal. After antibody immobilization, a cellular pellet, with a mixed cell population, was analyzed; the results indicated that the developed QCM immunosensor is highly specific, being able to detect and sort only CD34+ cells. Our study suggests that the proposed technology can detect and efficiently sort any kind of cell from samples with high complexity, being simple, selective, and providing for more convenient and time-saving operations. PMID:29182568
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Preparing near-surface heavy oil for extraction using microbial degradation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Busche, Frederick D.; Rollins, John B.; Noyes, Harold J.
In one embodiment, the invention provides a system including at least one computing device for enhancing the recovery of heavy oil in an underground, near-surface crude oil extraction environment by performing a method comprising sampling and identifying microbial species (bacteria and/or fungi) that reside in the underground, near-surface crude oil extraction environment; collecting rock and fluid property data from the underground, near-surface crude oil extraction environment; collecting nutrient data from the underground, near-surface crude oil extraction environment; identifying a preferred microbial species from the underground, near-surface crude oil extraction environment that can transform the heavy oil into a lighter oil;more » identifying a nutrient from the underground, near-surface crude oil extraction environment that promotes a proliferation of the preferred microbial species; and introducing the nutrient into the underground, near-surface crude oil extraction environment.« less
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Bächle, Maria; Kohal, Ralf J
2004-12-01
Titanium is the standard material for dental and orthopaedical implants. The good biocompatibility has been proven in many experimental and clinical investigations. Different titanium topographies were tested in vitro using different cell culture models. The aim of this systematic review was to evaluate and summarize the medical/dental literature to assess on which kind of titanium surface structure the osteoblast-like osteosarcoma cells MG63 show the best proliferation and differentiation rate, and the best protein synthesis. A systematic search was carried out using different on-line databases (PubMed, Web of Science, Cochrane Library, International Poster Journal), supplemented by handsearch in selected journals and by examination of the bibliographies of the identified articles. Inclusion and exclusion criterias were applied when considering relevant articles. Studies which met the inclusion criteria were included and data extraction was undertaken by one reviewer. The search yielded 348 references. Nine articles referring to nine different studies were relevant to our question. Additionally 8 less relevant articles were identified. It was found that regularly textured surfaces of pure titanium with R(a) values (average roughness) of around 4 mum are well-accepted by MG63 cells. The surfaces and culture conditions vary widely. Therefore it is still difficult to recommend one particular surface. It seems that there are no differences in cell proliferation and differentiation on surfaces treated by blasting and etching. Standardization in fabrication and size of the different test surfaces as well as homogeneity in culture times and plating densities should be aspects for future research.
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NASA Astrophysics Data System (ADS)
Mochalskyy, S.; Wünderlich, D.; Ruf, B.; Franzen, P.; Fantz, U.; Minea, T.
2014-02-01
Decreasing the co-extracted electron current while simultaneously keeping negative ion (NI) current sufficiently high is a crucial issue on the development plasma source system for ITER Neutral Beam Injector. To support finding the best extraction conditions the 3D Particle-in-Cell Monte Carlo Collision electrostatic code ONIX (Orsay Negative Ion eXtraction) has been developed. Close collaboration with experiments and other numerical models allows performing realistic simulations with relevant input parameters: plasma properties, geometry of the extraction aperture, full 3D magnetic field map, etc. For the first time ONIX has been benchmarked with commercial positive ions tracing code KOBRA3D. A very good agreement in terms of the meniscus position and depth has been found. Simulation of NI extraction with different e/NI ratio in bulk plasma shows high relevance of the direct negative ion extraction from the surface produced NI in order to obtain extracted NI current as in the experimental results from BATMAN testbed.
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In vitro testing of Nd:YAG laser processed calcium phosphate coatings.
De Carlos, A; Lusquiños, F; Pou, J; León, B; Pérez-Amor, M; Driessens, F C M; Hing, K; Best, S; Bonfield, W
2006-11-01
Nd:YAG laser cladding is a new method for deposition of a calcium phosphate onto metallic surfaces of interest in implantology. The aim of this study was to compare the biologic response of MG-63 human osteoblast-like cells grown on Ti-6Al-4V substrates coated with a calcium phosphate layer applied using different methods: plasma spraying as reference material and Nd:YAG laser cladding as test material. Tissue culture polystyrene was used as negative control. The Nd:YAG laser clad material showed a behaviour similar to the reference material, plasma spray, respective to cell morphology (SEM observations), cell proliferation (AlamarBlue assay) and cytotoxicity of extracts (MTT assay). Proliferation, as measured by the AlamarBlue assay, showed little difference in the metabolic activity of the cells on the materials over an 18 day culture period. There were no significant differences in the cellular growth response on the test material when compared to the ones exhibited by the reference material. In the solvent extraction test all the extracts had some detrimental effect on cellular activity at 100% concentration, although cells incubated in the test material extract showed a proliferation rate similar to that of the reference material. To better understand the scope of these results it should be taken into account that the Nd:YAG clad coating has recently been developed. The fact that its in vitro performance is comparable to that produced by plasma spray, a material commercially available for more than ten years, indicates that this new laser based method could be of commercial interest in the near future.
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Rapid analysis of foodborne pathogens by surface-enhanced Raman spectroscopy
NASA Astrophysics Data System (ADS)
Sengupta, Atanu; Shende, Chetan; Huang, Hermes; Farquharson, Stuart; Inscore, Frank
2012-05-01
Foodborne diseases resulting from Campylobacter, Escherichia, Listeria, Salmonella, Shigella and Vibrio species affect as many as 76 million persons in the United States each year, resulting in 325,000 hospitalizations and 5,000 deaths. The challenge to preventing distribution and consumption of contaminated foods lies in the fact that just a few bacterial cells can rapidly multiply to millions, reaching infectious doses within a few days. Unfortunately, current methods used to detect these few cells rely on lengthy growth enrichment steps that take a similar amount of time (1 to 4 days). Consequently, there is a critical need for an analyzer that can rapidly extract and detect foodborne pathogens in 1-2 hours (not days), at 100 colony forming units per gram of food, and with a specificity that differentiates from indigenous microflora, so that false alarms are eliminated. In an effort to meet this need, we have been developing a sample system that extracts such pathogens from food, selectively binds these pathogens, and produces surface-enhanced Raman spectra (SERS). Here we present preliminary SERS measurements of Listeria and Salmonella.
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NASA Astrophysics Data System (ADS)
Kalziqi, Arben; Yunker, Peter; Thomas, Jacob
Unlike equilibrium atomic solids, biofilms do not experience significant thermal fluctuations at the constituent level. However, cells inside the biofilm stochastically die and reproduce, provoking a mechanical response. We investigate the mechanical response of biofilms to the death and reproduction of cells by measuring surface-height fluctuations of biofilms with two mutual predator strains of Vibrio cholerae which kill one another on contact via the Type VI Secretion System. Biofilm surface topography is measured in the homeostatic limit, wherein cell division and death occur at roughly the same rate, via white light interferometry. Although biofilms are far from equilibrium systems, measured height correlation functions line up with expectations from a generalized fluctuation-response relation derived from replication and death events, as predicted by Risler et al. (PRL 2015). Using genetically modified strains of V. cholerae which cannot kill, we demonstrate that extracted effective temperatures increase with the amount of death and reproduction. Thus, high-precision measurement of surface topography reveals the physical consequences of death and reproduction within a biofilm, providing a new approach to studying interactions between bacteria and cells.
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Peters, Wladimir; Drueppel, Verena; Kusche-Vihrog, Kristina; Schubert, Carola; Oberleithner, Hans
2012-01-01
The endothelial glycocalyx (eGC) plays a pivotal role in the physiology of the vasculature. By binding plasma proteins, the eGC forms the endothelial surface layer (ESL) which acts as an interface between bloodstream and endothelial cell surface. The functions of the eGC include mechanosensing of blood flow induced shear stress and thus flow dependent vasodilation. There are indications that levels of plasma sodium concentrations in the upper range of normal and beyond impair flow dependent regulation of blood pressure and may therefore increase the risk for hypertension. Substances, therefore, that prevent sodium induced endothelial dysfunction may be attractive for the treatment of cardiovascular disease. By means of combined atomic force - epifluorescence microscopy we studied the impact of the hawthorn (Crataegus spp.) extract WS 1442, a herbal therapeutic with unknown mechanism of action, on the mechanics of the ESL of ex vivo murine aortae. Furthermore, we measured the impact of WS 1442 on the sodium permeability of endothelial EA.hy 926 cell monolayer. The data show that (i) the ESL contributes by about 11% to the total endothelial barrier resistance for sodium and (ii) WS 1442 strengthens the ESL resistance for sodium up to about 45%. This mechanism may explain some of the vasoprotective actions of this herbal therapeutic. PMID:22253842
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Peters, Wladimir; Drüppel, Verena; Drueppel, Verena; Kusche-Vihrog, Kristina; Schubert, Carola; Oberleithner, Hans
2012-01-01
The endothelial glycocalyx (eGC) plays a pivotal role in the physiology of the vasculature. By binding plasma proteins, the eGC forms the endothelial surface layer (ESL) which acts as an interface between bloodstream and endothelial cell surface. The functions of the eGC include mechanosensing of blood flow induced shear stress and thus flow dependent vasodilation. There are indications that levels of plasma sodium concentrations in the upper range of normal and beyond impair flow dependent regulation of blood pressure and may therefore increase the risk for hypertension. Substances, therefore, that prevent sodium induced endothelial dysfunction may be attractive for the treatment of cardiovascular disease. By means of combined atomic force-epifluorescence microscopy we studied the impact of the hawthorn (Crataegus spp.) extract WS 1442, a herbal therapeutic with unknown mechanism of action, on the mechanics of the ESL of ex vivo murine aortae. Furthermore, we measured the impact of WS 1442 on the sodium permeability of endothelial EA.hy 926 cell monolayer. The data show that (i) the ESL contributes by about 11% to the total endothelial barrier resistance for sodium and (ii) WS 1442 strengthens the ESL resistance for sodium up to about 45%. This mechanism may explain some of the vasoprotective actions of this herbal therapeutic.
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Hong, John; Hou, Bo; Lim, Jongchul; Pak, Sangyeon; Kim, Byung-Sung; Cho, Yuljae; Lee, Juwon; Lee, Young-Woo; Giraud, Paul; Lee, Sanghyo; Park, Jong Bae; Morris, Stephen M.; Snaith, Henry J.; Kim, Jong Min
2016-01-01
Colloidal quantum dots (CQDs) are extremely promising as photovoltaic materials. In particular, the tunability of their electronic band gap and cost effective synthetic procedures allow for the versatile fabrication of solar energy harvesting cells, resulting in optimal device performance. However, one of the main challenges in developing high performance quantum dot solar cells (QDSCs) is the improvement of the photo-generated charge transport and collection, which is mainly hindered by imperfect surface functionalization, such as the presence of surface electronic trap sites and the initial bulky surface ligands. Therefore, for these reasons, finding effective methods to efficiently decorate the surface of the as-prepared CQDs with new short molecular length chemical structures so as to enhance the performance of QDSCs is highly desirable. Here, we suggest employing hybrid halide ions along with the shortest heterocyclic molecule as a robust passivation structure to eliminate surface trap sites while decreasing the charge trapping dynamics and increasing the charge extraction efficiency in CQD active layers. This hybrid ligand treatment shows a better coordination with Pb atoms within the crystal, resulting in low trap sites and a near perfect removal of the pristine initial bulky ligands, thereby achieving better conductivity and film structure. Compared to halide ion-only treated cells, solar cells fabricated through this hybrid passivation method show an increase in the power conversion efficiency from 5.3% for the halide ion-treated cells to 6.8% for the hybrid-treated solar cells. PMID:29308200
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Imaging of blood antigen distribution on blood cells by thermal lens microscopy
NASA Astrophysics Data System (ADS)
Kimura, Hiroko; Sekiguchi, Kazuya; Nagao, Fumiko; Mukaida, Masahiro; Kitamori, Takehiko; Sawada, Tsuguo
2000-05-01
Blood group antigens on a cell were measured by a new microscopic method, i.e. thermal lens microscopy which involves spectrometry using a laser-induced thermal-lens effect. The blood group antigen was immunologically stained using antibody labeled with colloidal gold. Human leukocyte antigens (HLA) on lymphocytes and mononuclear leukocytes were observed by the thermal lens microscope, and Lewis blood group antigens on erythrocytes and polymorphonuclear leukocytes were also observed. The antigen distribution on each cell-surface was imaged using this technique. In spite of convex surface of living cells, colloidal gold was correctly quantified by adjusting the deviation of the focal point of the probe laser by the phase of the signal. In the measurement of leukocyte antigens, antigens of HLA-A, -B, -C loci on the lymphocytes were identified and quantitated by using a single cell. The image of HLA-A, -B, -C antigen distribution on a mononuclear leukocyte was obtained. In the measurement of erythrocyte antigens, a small quantity of Lewis antigens was detected on the cord erythrocytes. Localized small quantities of membrane antigens are better quantitated without extraction or cytolysis. Our thermal lens microscope is a powerful and highly sensitive analytical tool for detecting and quantitating localized antigens in single cells and/or cell-surface-associated molecules.
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Light extraction block with curved surface
Levermore, Peter; Krall, Emory; Silvernail, Jeffrey; Rajan, Kamala; Brown, Julia J.
2016-03-22
Light extraction blocks, and OLED lighting panels using light extraction blocks, are described, in which the light extraction blocks include various curved shapes that provide improved light extraction properties compared to parallel emissive surface, and a thinner form factor and better light extraction than a hemisphere. Lighting systems described herein may include a light source with an OLED panel. A light extraction block with a three-dimensional light emitting surface may be optically coupled to the light source. The three-dimensional light emitting surface of the block may includes a substantially curved surface, with further characteristics related to the curvature of the surface at given points. A first radius of curvature corresponding to a maximum principal curvature k.sub.1 at a point p on the substantially curved surface may be greater than a maximum height of the light extraction block. A maximum height of the light extraction block may be less than 50% of a maximum width of the light extraction block. Surfaces with cross sections made up of line segments and inflection points may also be fit to approximated curves for calculating the radius of curvature.
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Li, Xin; Hao, Feng; Zhao, Xingyue; Yin, Xuewen; Yao, Zhibo; Guo, Ying; Shen, Heping; Lin, Hong
2017-10-11
Electron-extraction layer (EEL) plays a critical role in determining the charge extraction and the power conversion efficiencies of the organometal-halide perovskite solar cells (PSCs). In this work, Ti-Fe-O ternary oxides were first developed to work as an efficient EEL in planar PSC. Compared with the widely used TiO x and the pure FeO x , the ternary composites show superior properties in multiple aspects including the excellent stability of the precursor solution, good coverage on the substrates, outstanding electrical properties, and suitable energy levels. By varying the Fe content from 0 to 100% in the Ti-Fe-O composites, the conductivity of the resultant compact layer was markedly improved, confirmed by consistent results from the conductive atomic force microscopy and the linear sweep voltammetry measurements. Meanwhile, the compositional engineering tunes the energy level alignment of the Ti-Fe-O EEL/CH 3 NH 3 PbI 3 interface to a region that is favorable for obtaining excellent charge-extraction property. The combinational advantages of the Ti-Fe-O composites significantly improved the photovoltaic performance of the as-prepared solar cells. An increase of over 20% in the short-circuit current (J SC ) density has been achieved due to a modified EEL conductivity and energy alignment with the perovskite layer. The reduction in the surface recombination and enhancement of the charge collection efficiency also result in about 15% increase in the fill factor. Notably, the device also showed remarkably alleviated hysteresis behavior, revealing a prominently inhibited surface recombination.
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NASA Astrophysics Data System (ADS)
Kumar, S.; Singh, A.; Dhar, A.
2017-08-01
The accurate estimation of the photovoltaic parameters is fundamental to gain an insight of the physical processes occurring inside a photovoltaic device and thereby to optimize its design, fabrication processes, and quality. A simulative approach of accurately determining the device parameters is crucial for cell array and module simulation when applied in practical on-field applications. In this work, we have developed a global particle swarm optimization (GPSO) approach to estimate the different solar cell parameters viz., ideality factor (η), short circuit current (Isc), open circuit voltage (Voc), shunt resistant (Rsh), and series resistance (Rs) with wide a search range of over ±100 % for each model parameter. After validating the accurateness and global search power of the proposed approach with synthetic and noisy data, we applied the technique to the extract the PV parameters of ZnO/PCDTBT based hybrid solar cells (HSCs) prepared under different annealing conditions. Further, we examine the variation of extracted model parameters to unveil the physical processes occurring when different annealing temperatures are employed during the device fabrication and establish the role of improved charge transport in polymer films from independent FET measurements. The evolution of surface morphology, optical absorption, and chemical compositional behaviour of PCDTBT co-polymer films as a function of processing temperature has also been captured in the study and correlated with the findings from the PV parameters extracted using GPSO approach.
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Arunachalam, Kantha Deivi; Arun, Lilly Baptista; Annamalai, Sathesh Kumar; Arunachalam, Aarrthy M
2015-01-01
Gymnema sylvestre is an ethno-pharmacologically important medicinal plant used in many polyherbal formulations for its potential health benefits. Silver nanoparticles (SNPs) were biofunctionalized using aqueous leaf extracts of G. sylvestre. The anticancer properties of the bioactive compounds and the biofunctionalized SNPs were compared using the HT29 human adenoma colon cancer cell line. The preliminary phytochemical screening for bioactive compounds from aqueous extracts revealed the presence of alkaloids, triterpenes, flavonoids, steroids, and saponins. Biofunctionalized SNPs were synthesized using silver nitrate and characterized by ultraviolet-visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, and X-ray diffraction for size and shape. The characterized biofunctionalized G. sylvestre were tested for its in vitro anticancer activity against HT29 human colon adenocarcinoma cells. The biofunctionlized G. sylvestre SNPs showed the surface plasmon resonance band at 430 nm. The scanning electron microscopy images showed the presence of spherical nanoparticles of various sizes, which were further determined using the Scherrer equation. In vitro cytotoxic activity of the biofunctionalized green-synthesized SNPs (GSNPs) indicated that the sensitivity of HT29 human colon adenocarcinoma cells for cytotoxic drugs is higher than that of Vero cell line for the same cytotoxic agents and also higher than the bioactive compound of the aqueous extract. Our results show that the anticancer properties of the bioactive compounds of G. sylvestre can be enhanced through biofunctionalizing the SNPs using the bioactive compounds present in the plant extract without compromising their medicinal properties.
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Influence of light-curing mode on the cytotoxicity of resin-based surface sealants.
Wegehaupt, Florian J; Tauböck, Tobias T; Attin, Thomas; Belibasakis, Georgios N
2014-05-06
Surface sealants have been successfully used in the prevention of erosive tooth wear. However, when multiple tooth surfaces should be sealed, the light-curing procedure is very time-consuming. Therefore, the aim of this study was to investigate whether reduced light-curing time (while maintaining similar energy density) has an influence on resin-based surface sealant cytotoxicity. Bovine dentine discs were treated as follows: group 1: untreated, groups 2-5: Seal&Protect and groups 6-9: experimental sealer. Groups 2 and 6 were light-cured (VALO LED light-curing device) for 40 s (1000 mW/cm2), groups 3 and 7 for 10 s (1000 mW/cm2), groups 4 and 8 for 7 s (1400 mW/cm2) and groups 5 and 9 for 3 s (3200 mW/cm2). Later, materials were extracted in culture medium for 24 h, and released lactate dehydrogenase (LDH) activity as a measure of cytotoxicity was determined photometrically after cells (dental pulp cells and gingival fibroblasts) were exposed to the extracts for 24 h. Three independent experiments, for both sample preparation and cytotoxicity testing, were performed. Overall, lowest cytotoxicity was observed for the unsealed control group. No significant influence of light-curing settings on the cytotoxicity was observed (p = 0.537 and 0.838 for pulp cells and gingival fibroblasts, respectively). No significant difference in the cytotoxicity of the two sealants was observed after light-curing with same light-curing settings (group 2 vs. 6, 3 vs. 7, 4 vs. 8 and 5 vs. 9: p > 0.05, respectively). Shortening the light-curing time, while maintaining constant energy density, resulted in no higher cytotoxicity of the investigated sealants.
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Preliminary Study of the Potential Extracts from Selected Plants to Improve Surface Cleaning
Vong, Ai Ting
2018-01-01
Environment hygiene is important for preventing infection and promoting a healthier environment in which to live or work. The goal of this study was to examine the antimicrobial effects of Citrus aurantifolia (key lime) juice and aqueous extracts of Cinnamomum iners (cinnamon) bark and Citrus hystrix (kaffir lime) leaves on the kinetic growth of Pseudomonas aeruginosa and methicillin resistance Staphylococcus aureus (MRSA). Antimicrobial activity was quantitatively evaluated using spectrophotometry and viable cell counts versus bacterial growth time. The fomite surface samples that were used in the second experiment were chosen randomly from the laboratories. They were assessed both before and after intervention using a mixture of commercial disinfectant detergent and lime juice. In the kinetic growth study, the lime juice effectively eliminated P. aeruginosa and MRSA. The cinnamon bark extract was more effective at inhibiting P. aeruginosa than MRSA. The kaffir lime leaf extract demonstrated bacteriostatic activity for the first 60 min, which then weakened after 90 min for both bacteria. The lime juice extract and commercial disinfectant mixture effectively disinfected the fomites. Further studies of the use of key lime juice as a disinfectant in the hospital environment should be conducted, as C. aurantifolia exhibits antibacterial activities against endemic microbes. PMID:29509658
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Effects of Anethum graveolens L. on fertility in male rats.
Monsefi, Malihezaman; Zahmati, Maryam; Masoudi, Mojtaba; Javidnia, Katayoun
2011-12-01
The effects of Anethum graveolens seed extract on fertility of male rats were investigated. Male Wistar rats were divided into five groups according to the treatment they received during 42 days: control, low dose (0.5 g/kg) and high dose (5 g/kg) of aqueous extracts, and low dose (0.045 g/kg) and high dose (0.45 g/kg) of ethanol extracts of Anethum graveolens seed. Sperm count and motility and testosterone concentration were measured. Sections of the testes, epididymis, and seminal vesicles were stained with peroxidase-conjugated lectins of Ulex europaeus agglutinin, peanut agglutinin, Dolichos biflorus agglutinin, soy bean agglutinin and concanavalin A. The treated male rats were mated with females and the crown-rump lengths and weights of their newborn pups were measured. No significant differences in sperm count, sperm motility or testosterone concentration were observed in the experimental groups. However, female rats did not become pregnant after mating with rats given the high dose of the ethanol extract. The distribution of terminal sugars on the epithelial surface of the reproductive structures decreased in the experimental groups. Anethum graveolens extract decreased fertility rate by modifying some terminal sugars on the cell surface of male reproductive organs involved in sperm maturation, capacitation and oocyte recognition.
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Anti-Quorum Sensing Activity of Substances Isolated from Wild Berry Associated Bacteria
Abudoleh, Suha M.; Mahasneh, Adel M.
2017-01-01
Background: Quorum Sensing (QS) is a mechanism used by bacteria to determine their physiological activities and coordinate gene expression based on cell to cell signaling. Many bacterial physiological functions are under the regulation of quorum sensing such as virulence, luminescence, motility, sporulation and biofilm formation. The aim of the present study was to isolate and characterize Quorum Sensing Inhibitory (QSI) substances from epiphytic bacteria residing on wild berries surfaces. Methods: Fifty nine bacterial isolates out of 600 screened bacteria were successfully isolated. These bacteria were obtained from berry surfaces of different plants in the wild forests of Ajloun-Jordan. Screening for QSI activity using Chromobacterium violaceum ATCC 12472 monitor strain, resulted in isolating 6 isolates exhibiting QSI activity only, 11 isolates with QSI and antibacterial activity, and 42 isolates with antibacterial activity only. Three potential isolates S 130, S 153, and S 664, were gram positive rods and spore formers, catalase positive and oxidase negative. These were chosen for further testing and characterization. Results: Different solvent extraction of the QSI substances based on polarity indicated that the activity of S 130 was in the butanol extract, S 153 activity in both chloroform and butanol; and for S 664, the activity was detected in the hexane extract. The chloroform extract of S 153 and hexane extract of S 664 were proteinaceous in nature while QSI substances of the butanol extract of S 130 and S 153 were non-proteinaceous. All the tested QSI substances showed a marked thermal stability when subjected at several time intervals to 70°C, with the highest stability observed for the butanol extract of S 153. Assessing the QSI substances using violacein quantification assay revealed varying degrees of activity depending upon the extracting solvent, type of the producer bacteria and the concentration of the substances. Conclusion: This study highlighted the potential of untapped reservoirs in nature to be used as a source of unique metabolite that may be further developed for therapy. The potential QSI substances included in this study are just one aspect to be further analyzed for use as biopharmaceutical agents. PMID:28090277
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Fang, Xiang; Ding, Jianning; Yuan, Ningyi; Sun, Peng; Lv, Minghang; Ding, Guqiao; Zhu, Chong
2017-02-22
Organic-inorganic halide perovskites have emerged as attractive materials for use in photovoltaic cells. Owing to the existence of dangling bonds at the grain boundaries between perovskite crystals, minimizing the charge recombination at the surface or grain boundaries by passivating these trap states has been identified to be one of the most important strategies for further optimization of device performance. Previous reports have mainly focused on surface passivation by inserting special materials such as graphene or fullerene between the electron transfer layer and the perovskite film. Here, we report an enhanced efficiency of mesoscopic perovskite solar cells by using graphene quantum dots (GQDs) to passivate the grain boundaries of CH 3 NH 3 PbI 3 . The highest efficiency (17.62%) is achieved via decoration with 7% GQDs, which is an 8.2% enhancement with respect to a pure perovskite based device. Various analyses including electrochemical impedance spectroscopy, time-resolved photoluminescence decay and open-circuit voltage decay measurements are employed in investigating the mechanism behind the improvement in device performance. The findings reveal two important roles played by GQDs in promoting the performance of perovskite solar cells - that GQDs are conducive to facilitating electron extraction and can effectively passivate the electron traps at the perovskite grain boundaries.
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Lee, Ilgyu; Han, Jong-In
2015-06-01
Simultaneous treatment (combining with cell disruption and lipid extraction) using hydrodynamic cavitation (HC) was applied to Nannochloropsis salina to demonstrate a simple and integrated way to produce oil from wet microalgae. A high lipid yield from the HC (25.9-99.0%) was observed compared with autoclave (16.2-66.5%) and ultrasonication (5.4-26.9%) in terms of the specific energy input (500-10,000 kJ/kg). The optimal conditions for the simultaneous treatment were established using a statistical approach. The efficiency of the simultaneous method was also demonstrated by comparing each separate treatment. The maximum lipid yield (predicted: 45.9% and experimental: 45.5%) was obtained using 0.89% sulfuric acid with a cavitation number of 1.17 for a reaction time of 25.05 min via response surface methodology. Considering its comparable extractability, energy-efficiency, and potential for scale-up, HC may be a promising method to achieve industrial-scale microalgae operation. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Arranz, E; Guri, A; Fornari, T; Mendiola, J A; Reglero, G; Corredig, M
2017-07-01
The digestion, absorption, uptake and bioavailability of a rosemary supercritical fluid extract encapsulated in oil in water emulsion were studied. Two emulsions with opposite surface charge were prepared, containing 7% canola oil, and either 2% lactoferrin or whey protein isolate. When absorption and uptake of carnosic acid and carnosol were followed on Caco-2 cell monolayers, there were no differences with protein type. However, when co-cultures of HT-29 MTX were employed, the presence of mucus caused a higher retention of carnosic acid in the apical layer for lactoferrin emulsions. The immune activity of the bioavailable fractions collected from cell absorption experiments was tested ex vivo on murine splenocytes. Although transport through the intestinal barrier models was low, the bioavailable fractions showed a significant effect on splenocytes proliferation. These results demonstrated the potential of using rosemary supercritical extract through protein stabilized oil in water emulsions, as a food with immunomodulatory functionality. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Belibasakis, G. N.; Johansson, A.; Wang, Y.; Chen, C.; Kalfas, S.; Lerner, U. H.
2005-01-01
Actinobacillus actinomycetemcomitans is associated with localized aggressive periodontitis, a disease characterized by rapid loss of the alveolar bone surrounding the teeth. Receptor activator of NF-κB Ligand (RANKL) and osteoprotegerin (OPG) are two molecules that regulate osteoclast formation and bone resorption. RANKL induces osteoclast differentiation and activation, whereas OPG blocks this process by acting as a decoy receptor for RANKL. The purpose of this study was to investigate the effect of A. actinomycetemcomitans on the expression of RANKL and OPG in human gingival fibroblasts and periodontal ligament cells. RANKL mRNA expression was induced in both cell types challenged by A. actinomycetemcomitans extract, whereas OPG mRNA expression remained unaffected. Cell surface RANKL protein was also induced by A. actinomycetemcomitans, whereas there was no change in OPG protein secretion. A cytolethal distending toxin (Cdt) gene-knockout strain of A. actinomycetemcomitans did not induce RANKL expression, in contrast to its wild-type strain. Purified Cdt from Haemophilus ducreyi alone, or in combination with extract from the A. actinomycetemcomitans cdt mutant strain, induced RANKL expression. Pretreatment of A. actinomycetemcomitans wild-type extract with Cdt antiserum abolished RANKL expression. In conclusion, A. actinomycetemcomitans induces RANKL expression in periodontal connective tissue cells. Cdt is crucial for this induction and may therefore be involved in the pathological bone resorption during the process of localized aggressive periodontitis. PMID:15618171
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Korayem, M H; Shahali, S; Rastegar, Z
2018-06-01
Plasma membrane of most cells is not smooth. The surfaces of both small and large micropermeable cells are folded and corrugated which makes mammalian cells to have a larger membrane surface than the supposed ideal mode, that is, the smooth sphere of the same volume. Since cancer is an anthropic disease, cancer cells tend to have a larger membrane area than normal cells. Therefore, cancer cells have higher folding factor and larger radius than normal and healthy cells. On the other hand, the prevalence of breast cancer has prompted researchers to improve the treatment options raised for the disease in the past. In this paper, the impact of folding factor of the cell surface has been investigated. Considering that AFM is one of the most effective tools in performing the tests at micro- and nanoscales, it was used to determine the topography of MCF10 cells and then the resulting images and results were used to experimentally extract the folding factor of cells. By applying this factor in the Hertz, DMT and JKR contact models in the elastic and viscoelastic states, these models have been modified and the simulation of the three models shows that the simulation results are closer to the experimental results by considering the folding in the calculations. Additionally, the simulation of 3D manipulation has been done in both elastic and viscoelastic states with and without consideration of folding. Finally, the results were compared to investigate the effects of folding of the cell surface to the critical force and critical time of sliding and rolling in contact with the substrate and AFM tip in the 3D manipulation model.
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Simpson, Brent W; Owens, Tristan W; Orabella, Matthew J; Davis, Rebecca M; May, Janine M; Trauger, Sunia A; Kahne, Daniel; Ruiz, Natividad
2016-10-18
The surface of most Gram-negative bacteria is covered with lipopolysaccharide (LPS), creating a permeability barrier against toxic molecules, including many antimicrobials. To assemble LPS on their surface, Gram-negative bacteria must extract newly synthesized LPS from the inner membrane, transport it across the aqueous periplasm, and translocate it across the outer membrane. The LptA to -G proteins assemble into a transenvelope complex that transports LPS from the inner membrane to the cell surface. The Lpt system powers LPS transport from the inner membrane by using a poorly characterized ATP-binding cassette system composed of the ATPase LptB and the transmembrane domains LptFG. Here, we characterize a cluster of residues in the groove region of LptB that is important for controlling LPS transport. We also provide the first functional characterization of LptFG and identify their coupling helices that interact with the LptB groove. Substitutions at conserved residues in these coupling helices compromise both the assembly and function of the LptB 2 FG complex. Defects in LPS transport conferred by alterations in the LptFG coupling helices can be rescued by changing a residue in LptB that is adjacent to functionally important residues in the groove region. This suppression is achieved by increasing the ATPase activity of the LptB 2 FG complex. Taken together, these data identify a specific binding site in LptB for the coupling helices of LptFG that is responsible for coupling of ATP hydrolysis by LptB with LptFG function to achieve LPS extraction. Lipopolysaccharide (LPS) is synthesized at the cytoplasmic membrane of Gram-negative bacteria and transported across several compartments to the cell surface, where it forms a barrier that protects these organisms from antibiotics. The LptB 2 FG proteins form an ATP-binding cassette (ABC) transporter that uses energy from ATP hydrolysis in the cytoplasm to facilitate extraction of LPS from the outer face of the cytoplasmic membrane prior to transport to the cell surface. How ATP hydrolysis is coupled with LPS release from the membrane is not understood. We have identified residues at the interface between the ATPase and the transmembrane domains of this heteromeric ABC complex that are important for LPS transport, some of which coordinate ATPase activity with LPS release. Copyright © 2016 Simpson et al.
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Mohsenipour, Zeinab; Hassanshahian, Mehdi
2015-01-01
Background: Garlic is considered a rich source of many compounds, which shows antimicrobial effects. The ability of microorganisms to adhere to both biotic and abiotic surfaces and to form biofilm is responsible for a number of diseases of chronic nature, demonstrating extremely high resistance to antibiotics. Bacterial biofilms are complex communities of sessile microorganisms, embedded in an extracellular matrix and irreversibly attached to various surfaces. Objectives: The present study evaluated the antimicrobial activity of Allium sativum extract against the biofilms of six pathogenic bacteria and their free-living forms. The clinical isolates in this study had not been studied in any other studies, especially in regard to biofilm disruption and inhibition of biofilm cell metabolic activity. Materials and Methods: Antimicrobial activities of A. sativum L. extracts (methanol and ethanol extracts) against planktonic forms of bacteria were determined using the disc diffusion method. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values were evaluated by a macrobroth dilution technique. The anti-biofilm effects were assessed by microtiter plate method. Results: The results showed that the A. sativum L. extract discs did not have any zone of inhibition for the tested bacteria. However, The MIC values of A. sativum L. extracts (0.078 - 2.5 mg/mL) confirmed the high ability of these extracts for inhibition of planktonic bacteria. A. sativum L. extracts were efficient to inhibit biofilm structures and the concentration of each extract had a direct relation with the inhibitory effect. Conclusions: Finally, it can be suggested that the extracts of this plant be applied as antimicrobial agents against these pathogens, particularly in biofilm forms. PMID:26464762
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Change of Bioactive Constituent in Clinacanthus nutans Leaves under Sun Drying
NASA Astrophysics Data System (ADS)
Abdullah, Sriyana; Aziz, Muhamad Faris Abdul
2018-03-01
Clinacanthus nutans (C. nutans) or locally known as belalai gajah is a folk medicine since ancient time. This research project was established to investigate the effects of under sun drying on the C. nutans bioactive constituent. The drying experiments were conducted using different drying surfaces i.e. perforated, black polythene and white polythene. The fresh and dried leaves were then extracted using a sonicator to evaluate its bioactive constituent. The total phenolic content (TPC) in the C. nutans extracts were determined using Follin Ciocalteu reagent method to represent the bioactive constituent. Drying over the white polythene surface showed the slowest reduction of moisture content as compared to the perforated polythene and black surfaces. Results also showed no significant effect of the drying surfaces on the TPC. However, the TPC in the dried leaves was significantly higher than in the fresh leaves. This may be due to the plant cells response to abiotic stress and the inhibition of oxidation enzymes. Therefore, drying C. nutanc leaves under sun light could be considered in order to preserve the concentration of phenolic compounds and for minimizing energy consumption.
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Shao, P; Zhang, J F; Chen, X X; Sun, P L
2015-08-01
An efficient method for the rapid extraction, separation and purification of chlorogenic acid (CGA) from by-products of Eucommia Ulmoides Oliver (E. ulmoides) by microwave-assisted extraction (MAE) coupled with high-speed counter-current chromatography (HSCCC) was developed. The optimal MAE parameters were evaluated by response surface methodology (RSM), and they were extraction time of 12 min, microwave power of 420 W, ethanol concentration of 75 %, solvent/sample ratio of 30:1 (mL/g), yield of CGA reached 3.59 %. The crude extract was separated and purified directly by HSCCC using ethyl acetate-butyl alcohol-water (3:1:4, v/v) as the two-phase solvent system. The 14.5 mg of CGA with the purity of 98.7 % was obtained in one-step separation from 400 mg of crude extract. The chemical structure of CGA was verified with IR, ESI-MS analysis. Meanwhile, the purified CGA extract was evaluated by MTT assay and results indicate that CGA extract exhibited potential anti-tumor activity for AGS gastric cancer cell.
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Extraction, purification and anti-proliferative activities of polysaccharides from Lentinus edodes.
Zhao, Yong-Ming; Wang, Jin; Wu, Zhi-Gang; Yang, Jian-Ming; Li, Wei; Shen, Li-Xia
2016-12-01
In this study, the enzyme-assisted extraction of polysaccharides from Lentinus edodes (LEPs) was optimized by response surface methodology, and a preliminary characterization of the extracted LEPs and their anti-proliferative activities were investigated. An orthogonal assay was constructed to determine the optimal amounts of cellulase, papain and pectinase, which were 15, 20 and 15g/kg, respectively. Then effects of extraction conditions were evaluated and optimized using a Box-Behnken design. The results showed that the highest polysaccharides yield of 15.65% was achieved with an extraction temperature of 54°C, pH 5.0, enzymatic treatment time of 93min and a liquid/material ratio of 29:1mL/g, which correlated well with the predicted yield of 15.58%. Subsequently, the crude LEPs were further purified by DEAE-cellulose and Sephadex-100 chromatography to obtain two fractions, which were designated as LEP-1 and LEP-2 and their monosaccharide compositions were characterized by GC. Fourier-transform infrared spectra demonstrated that LEP-1 and LEP-2 were distinct from each other regarding their chemical structures. In addition, the LEPs exhibited inhibition of cell proliferation on HCT-116 and HeLa cells in vitro. In summary, this study provides an efficient enzyme-assisted extraction for LEPs, which can be used as natural antitumor agents in the pharmaceutical and functional food industries. Copyright © 2016 Elsevier B.V. All rights reserved.
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Silica nanoparticle based techniques for extraction, detection, and degradation of pesticides.
Bapat, Gandhali; Labade, Chaitali; Chaudhari, Amol; Zinjarde, Smita
2016-11-01
Silica nanoparticles (SiNPs) find applications in the fields of drug delivery, catalysis, immobilization and sensing. Their synthesis can be mediated in a facile manner and they display broad range compatibility and stability. Their existence in the form of spheres, wires and sheets renders them suitable for varied purposes. This review summarizes the use of silica nanostructures in developing techniques for extraction, detection and degradation of pesticides. Silica nanostructures on account of their sorbent properties, porous nature and increased surface area allow effective extraction of pesticides. They can be modified (with ionic liquids, silanes or amines), coated with molecularly imprinted polymers or magnetized to improve the extraction of pesticides. Moreover, they can be altered to increase their sensitivity and stability. In addition to the analysis of pesticides by sophisticated techniques such as High Performance Liquid Chromatography or Gas chromatography, silica nanoparticles related simple detection methods are also proving to be effective. Electrochemical and optical detection based on enzymes (acetylcholinesterase and organophosphate hydrolase) or antibodies have been developed. Pesticide sensors dependent on fluorescence, chemiluminescence or Surface Enhanced Raman Spectroscopic responses are also SiNP based. Moreover, degradative enzymes (organophosphate hydrolases, carboxyesterases and laccases) and bacterial cells that produce recombinant enzymes have been immobilized on SiNPs for mediating pesticide degradation. After immobilization, these systems show increased stability and improved degradation. SiNP are significant in developing systems for effective extraction, detection and degradation of pesticides. SiNPs on account of their chemically inert nature and amenability to surface modifications makes them popular tools for fabricating devices for 'on-site' applications. Copyright © 2016 Elsevier B.V. All rights reserved.
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Zhang, Lili; Yu, Yang; Li, Xinhua; Li, Xiaona; Zhang, Huajiang; Zhang, Zhen; Xu, Yunhe
2017-01-01
In the current study, we focused on the mechanism underlying starch flocculation by the sweet potato sour liquid. The traditional microbial techniques and 16S rDNA sequencing revealed that Lactobacillus was dominant flocculating microorganism in sour liquid. In total, 86 bacteria, 20 yeasts, and 10 molds were isolated from the sour liquid and only eight Lactobacillus species exhibited flocculating activity. Lactobacillus paracasei subsp. paracasei L1 strain with a high flocculating activity was isolated and identified, and the mechanism of starch flocculation was examined. L. paracasei subsp. paracasei L1 cells formed chain-like structures on starch granules. Consequently, these cells connected the starch granules to one another, leading to formation of large flocs. The results of various treatments of L1 cells indicated that bacterial surface proteins play a role in flocculation and L1 cells adhered to the surface of starch granules via specific surface proteins. These surface starch-binding proteins were extracted using the guanidine hydrochloride method; 10 proteins were identified by mass spectrometry: three of these proteins were glycolytic enzymes; two were identified as the translation elongation factor Tu; one was a cell wall hydrolase; one was a surface antigen; one was lyzozyme M1; one was a glycoside hydrolase; and one was an uncharacterized proteins. This study will paves the way for future industrial application of the L1 isolate in starch processing and food manufacturing. PMID:28791000
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ingram, Jani Cheri; Lehman, Richard Michael; Bauer, William Francis
We report the use of a surface analysis approach, static secondary ion mass spectrometry (SIMS) equipped with a molecular (ReO4-) ion primary beam, to analyze the surface of intact microbial cells. SIMS spectra of 28 microorganisms were compared to fatty acid profiles determined by gas chromatographic analysis of transesterfied fatty acids extracted from the same organisms. The results indicate that surface bombardment using the molecular primary beam cleaved the ester linkage characteristic of bacteria at the glycerophosphate backbone of the phospholipid components of the cell membrane. This cleavage enables direct detection of the fatty acid conjugate base of intact microorganismsmore » by static SIMS. The limit of detection for this approach is approximately 107 bacterial cells/cm2. Multivariate statistical methods were applied in a graded approach to the SIMS microbial data. The results showed that the full data set could initially be statistically grouped based upon major differences in biochemical composition of the cell wall. The gram-positive bacteria were further statistically analyzed, followed by final analysis of a specific bacterial genus that was successfully grouped by species. Additionally, the use of SIMS to detect microbes on mineral surfaces is demonstrated by an analysis of Shewanella oneidensis on crushed hematite. The results of this study provide evidence for the potential of static SIMS to rapidly detect bacterial species based on ion fragments originating from cell membrane lipids directly from sample surfaces.« less
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Åvall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi
2003-01-01
Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium. PMID:12676705
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Avall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi
2003-04-01
Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium.
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NASA Astrophysics Data System (ADS)
Suhaimi, Suriati; Mohamed Siddick, Siti Zubaidah; Ahmad Hambali, Nor Azura Malini; Retnasamy, Vithyacharan; Abdul Wahid, Mohamad Halim; Mohamad Shahimin, Mukhzeer
2017-02-01
Natural pigmentations of Ardisia, Bawang Sabrang, Harum Manis mango, Oxalis Triangularis and Rosella were used to study the general trend in performance of dyes as a photosensitizer in the application of dye-sensitized solar cells (DSSCs) based on optical light absorbance and photoelectrochemical characteristics. From the Ultraviolet-Visible Spectrophotometer with the recorded absorption measurements in the range between 400 nm to 800 nm, the dyes extracted from Rosella and Oxalis Triangularis in water solvent exhibited the conversion efficiency up to 0.68% and 0.67%, respectively. The light absorbance peak for dye extracted from Ardisia, Bawang Sabrang, Oxalis Triangularis and Rosella in water and ethanol solvent resulted in the range between 500 nm to 650 nm, while the Harum Manis mango resulted in the broader spectra in both water and ethanol solvent. The light absorbance spectra of each the dyes shows shifted wavelength spectrum when the extracted dye is adsorbed onto TiO2 film surface that might influenced the absorption of light by TiO2 particle in the visible region. The capabilities of the dyes to absorb light when bonded onto the TiO2 photoanode was found to be significant with the current-voltage conversion of the cell. The results demonstrates just the tip of the vastness of natural dyes' (native to tropical region) feasibility and applicability as a photosensitizer.
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Yang, Bin; Mahjouri-Samani, Masoud; Rouleau, Christopher M.; ...
2016-06-10
A promising way to advance perovskite solar cells is to improve the quality of the electron transport material e.g., titanium dioxide (TiO 2) in a direction that increases electron transport and extraction. Although dense TiO 2 films are easily grown in solution, efficient electron extraction suffers due to a lack of interfacial contact area with the perovskite. Conversely, mesoporous films do offer high surface-area-to-volume ratios, thereby promoting efficient electron extraction, but their morphology is relatively difficult to control via conventional solution synthesis methods. Here, a pulsed laser deposition method was used to assemble TiO 2 nanoparticles into TiO 2 hierarchicalmore » nanoarchitectures having the anatase crystal structure, and prototype solar cells employing these structures yielded power conversion efficiencies of ~ 14%. Our approach demonstrates a way to grow high aspect-ratio TiO 2 nanostructures for improved interfacial contact between TiO 2 and perovskite materials, leading to high electron-hole pair separation and electron extraction efficiencies for superior photovoltaic performance. In addition, compared to conventional solution-processed TiO 2 films that require 500 °C to obtain a good crystallinity, our relatively low temperature (300 °C) TiO 2 processing method may promote reduced energy-consumption during device fabrication as well as enable compatibility with various flexible polymer substrates.« less
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Li, Dan; Qian, Yan; Tian, Yu-Jia; Yuan, Shi-Meng; Wei, Wei; Wang, Gang
2017-04-07
As new green solvents, ionic liquids (ILs) have been generally applied in the extraction and separation of natural product. In this study, microwave assisted extraction based on IL (IL-MAE) was firstly employed to extract total biflavonoids from Selaginella doederleinii . Based on single-factor experiment, microwave power (300-700 W), extract time (30-50 min) and extract temperature (40-60 °C) on total bioflavonoids and antioxidant activities of the extracts were further investigated by a Box-Behnken design of response surface methodology (RSM) selecting total bioflavonoids yields and IC 50 of radical scavenging as index. Besides antioxidant activity of the extract was evaluated by a 2,2-diphenyl-1-picrylhydarzyl (DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate (ABTS) radical scavenging assay, ferric reducing power assay and chelation of ferrous ions assay, and then anticaner activity was also researched against A549 cell line and 7721 cell line. The results illustrated that three factors and their interactions could be well suited for second-order polynomial models ( p < 0.05). Through process parameters, optimization of the extract (460 W, 40 min, and 45 °C) and detection of bioactivity, the yield of total bioflavonoids was 16.83 mg/g and IC 50 value was 56.24 μg/mL, respectively, indicating the extract has better anti-oxidation effect and antitumor activity. Furthermore, IL-MAE was the most efficient extracting method compared with MAE and Soxhlet extraction, which could improve extraction efficiency in a shorter time and at a lower temperature. In general, ILs-MAE was first adopted to establish a novel and green extraction process on the yields of total biflavonoids from S. doederleinii . In addition, the extract of containing biflavones showed potent antioxidant and anticancer capacity as a utilized valuable bioactive source for natural medicine.
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Jaramillo, Isabel C; Sturrock, Anne; Ghiassi, Hossein; Woller, Diana J; Deering-Rice, Cassandra E; Lighty, JoAnn S; Paine, Robert; Reilly, Christopher; Kelly, Kerry E
2018-03-21
The physicochemical properties of combustion particles that promote lung toxicity are not fully understood, hindered by the fact that combustion particles vary based on the fuel and combustion conditions. Real-world combustion-particle properties also continually change as new fuels are implemented, engines age, and engine technologies evolve. This work used laboratory-generated particles produced under controlled combustion conditions in an effort to understand the relationship between different particle properties and the activation of established toxicological outcomes in human lung cells (H441 and THP-1). Particles were generated from controlled combustion of two simple biofuel/diesel surrogates (methyl decanoate and dodecane/biofuel-blended diesel (BD), and butanol and dodecane/alcohol-blended diesel (AD)) and compared to a widely studied reference diesel (RD) particle (NIST SRM2975/RD). BD, AD, and RD particles exhibited differences in size, surface area, extractable chemical mass, and the content of individual polycyclic aromatic hydrocarbons (PAHs). Some of these differences were directly associated with different effects on biological responses. BD particles had the greatest surface area, amount of extractable material, and oxidizing potential. These particles and extracts induced cytochrome P450 1A1 and 1B1 enzyme mRNA in lung cells. AD particles and extracts had the greatest total PAH content and also caused CYP1A1 and 1B1 mRNA induction. The RD extract contained the highest relative concentration of 2-ring PAHs and stimulated the greatest level of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNFα) cytokine secretion. Finally, AD and RD were more potent activators of TRPA1 than BD, and while neither the TRPA1 antagonist HC-030031 nor the antioxidant N-acetylcysteine (NAC) affected CYP1A1 or 1B1 mRNA induction, both inhibitors reduced IL-8 secretion and mRNA induction. These results highlight that differences in fuel and combustion conditions affect the physicochemical properties of particles, and these differences, in turn, affect commonly studied biological/toxicological responses.
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CEKICI, Ali; MADEN, Ilay; YILDIZ, Sercan; SAN, Tangul; ISIK, Gulden
2013-01-01
Background: Periodontal regeneration is dependent on the uninterrupted adhesion, maturation and absorption of fibrin clots to a periodontally compromised root surface. The modification of the root surface with different agents has been used for better fibrin clot formation and blood cell attachment. It is known that Er:YAG laser application on dentin removes the smear layer succesfully. Aim: The aim of this study is to observe blood cell attachment and fibrin network formation following ER:YAG laser irradiation on periodontally compromised root surfaces in comparison to chemical root conditioning techniques in vitro. Materials and methods: 40 dentin blocks prepared from freshly extracted periodontally compromised hopeless teeth. Specimens were divided in 5 groups; those applied with PBS, EDTA, Citric acid and Er:YAG. They were further divided into two groups: those which had received these applications, and the control group. The specimens were evaluated with scanning electron microscope and micrographs were taken. Smear layer and blood cell attachment scoring was performed. Results: In the Er:YAG laser applied group, smear layer were totally removed. In the blood applied specimens, better fibrin clot formation and blood cell attachment were observed in the Er:YAG group. In the group that had been applied with citric acid, the smear layer was also removed. The smear layer could not be fully removed in the EDTA group. Conclusion: Er:YAG laser application on the root dentin seems to form a suitable surface for fibrin clot formation and blood cell attachment. Further clinical studies to support these results are necessitated. PMID:23533017
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Rotter, V; Boss, M A; Baltimore, D
1981-04-01
Abelson murine leukemia virus (A-MuLV)-transformed cells, simian virus 40 (SV40)-transformed cells, and chemically transformed cells all have increased levels of a 50,000-molecular-weight host cell protein. The protein was detected with sera raised to the A-MuLV-transformed and chemically transformed cells and was tightly bound to T-antigen in extracts of SV40-transformed cells. Partial protease digests showed that the proteins from all three sources were indistinguishable. The three proteins were phosphorylated in cells, and the linkage of phosphate to the A-MuLV-associated P50 was to a serine residue. By immunofluorescence methods, P50-related protein was found on the surface of both normal lymphoid cells and A-MuLV-transformed lymphoid cells, but cell fractionation showed that the majority of P50 was free in the cytoplasm of the transformed cells. Immunofluorescence also showed that P50 was found in granules in the cytoplasm of both untransformed and SV40-transformed fibroblasts. Other cells gave indistinct patterns. Cocapping experiments showed that the A-MuLV-specified P120 protein is weakly associated with the surface P50-related protein of lymphoid cells, but no association of P120 and P50 could be demonstrated by immunoprecipitation methods. Although a monoclonal antiserum to P50 was used in many of these studies, the identity of the bulk P50 protein with the molecules that are reactive at the cell surface requires further study.
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Injurious effects of wool and grain dusts on alveolar epithelial cells and macrophages in vitro.
Brown, D M; Donaldson, K
1991-01-01
Epidemiological studies of workers in wool textile mills have shown a direct relation between the concentration of wool dust in the air and respiratory symptoms. Injurious effects of wool dust on the bronchial epithelium could be important in causing inflammation and irritation. A pulmonary epithelial cell line in vitro was therefore used to study the toxic effects of wool dust. Cells of the A549 epithelial cell line were labelled with 51Cr and treated with whole wool dusts and extracts of wool, after which injury was assessed. Also, the effects of grain dust, which also causes a form of airway obstruction, were studied. The epithelial injury was assessed by measuring 51Cr release from cells as an indication of lysis, and by monitoring cells which had detached from the substratum. No significant injury to A549 cells was caused by culture with any of the dusts collected from the air but surface "ledge" dust caused significant lysis at some doses. Quartz, used as a toxic control dust, caused significant lysis at the highest concentration of 100 micrograms/well. To determine whether any injurious material was soluble the dusts were incubated in saline and extracts collected. No extracts caused significant injury to epithelial cells. A similar lack of toxicity was found when 51Cr labelled control alveolar macrophages were targets for injury. Significant release of radiolabel was evident when macrophages were exposed to quartz at concentrations of 10 and 20 micrograms/well, there being no significant injury with either wool or grain dusts. These data suggest that neither wool nor grain dust produce direct injury to epithelial cells, and further studies are necessary to explain inflammation leading to respiratory symptoms in wool and grain workers. PMID:2015211
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Takahashi, Hiroki; Ayala, Isabel; Bardet, Michel; De Paëpe, Gaël; Simorre, Jean-Pierre; Hediger, Sabine
2013-04-03
Dynamic nuclear polarization (DNP) enhanced solid-state nuclear magnetic resonance (NMR) has recently emerged as a powerful technique for the study of material surfaces. In this study, we demonstrate its potential to investigate cell surface in intact cells. Using Bacillus subtilis bacterial cells as an example, it is shown that the polarizing agent 1-(TEMPO-4-oxy)-3-(TEMPO-4-amino)propan-2-ol (TOTAPOL) has a strong binding affinity to cell wall polymers (peptidoglycan). This particular interaction is thoroughly investigated with a systematic study on extracted cell wall materials, disrupted cells, and entire cells, which proved that TOTAPOL is mainly accumulating in the cell wall. This property is used on one hand to selectively enhance or suppress cell wall signals by controlling radical concentrations and on the other hand to improve spectral resolution by means of a difference spectrum. Comparing DNP-enhanced and conventional solid-state NMR, an absolute sensitivity ratio of 24 was obtained on the entire cell sample. This important increase in sensitivity together with the possibility of enhancing specifically cell wall signals and improving resolution really opens new avenues for the use of DNP-enhanced solid-state NMR as an on-cell investigation tool.
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Xylella fastidiosa Afimbrial Adhesins Mediate Cell Transmission to Plants by Leafhopper Vectors▿
Killiny, Nabil; Almeida, Rodrigo P. P.
2009-01-01
The interactions between the economically important plant-pathogenic bacterium Xylella fastidiosa and its leafhopper vectors are poorly characterized. We used different approaches to determine how X. fastidiosa cells interact with the cuticular surface of the foreguts of vectors. We demonstrate that X. fastidiosa binds to different polysaccharides with various affinities and that these interactions are mediated by cell surface carbohydrate-binding proteins. In addition, competition assays showed that N-acetylglucosamine inhibits bacterial adhesion to vector foregut extracts and intact wings, demonstrating that attachment to leafhopper surfaces is affected in the presence of specific polysaccharides. In vitro experiments with several X. fastidiosa knockout mutants indicated that hemagglutinin-like proteins are associated with cell adhesion to polysaccharides. These results were confirmed with biological experiments in which hemagglutinin-like protein mutants were transmitted to plants by vectors at lower rates than that of the wild type. Furthermore, although these mutants were defective in adhesion to the cuticle of vectors, their growth rate once attached to leafhoppers was similar to that of the wild type, suggesting that these proteins are important for initial adhesion of X. fastidiosa to leafhoppers. We propose that X. fastidiosa colonization of leafhopper vectors is a complex, stepwise process similar to the formation of biofilms on surfaces. PMID:19011051
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Zhang, Tian-Tian; Yang, Li; Jiang, Jian-Guo
2015-07-01
Dried and unripe fruit of Rubus chingii Hu, known as "Fu-pen-zi" in Chinese, has been used as a food and tonic in China for a long time. In order to analyze its effective ingredients, polysaccharides, flavonoids, saponins and alkaloids were extracted from the unripe fruits and their contents were determined. The in vitro antioxidant, anticomplementary and anticancer activities against human lung adenocarcinoma A549 cells of the four major constituents were investigated. Results showed that total flavonoids exhibited an obvious antioxidant activity, which was very close to ascorbic acid. The anticomplementary and anticancer activities of flavonoids were also the best among the four chemical compositions. Therefore, extraction process optimization of flavonoids was conducted using response surface methodology. The optimal conditions were as follows: extraction temperature 72.8 °C, ethanol concentration 30.67%, extraction time 2.66 h, and a liquid/solid ratio of 19.54 : 1. In addition, total flavonoids were subsequently separated by column chromatography and the major flavonoid was identified as tiliroside. Further experimental data revealed that tiliroside treatment could suppress the proliferation and induced the apoptosis of A549 cells.
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Impact of solvent extraction organics on bioleaching by Acidithiobacillus ferrooxidans
NASA Astrophysics Data System (ADS)
Yu, Hualong; Liu, Xiaorong; Shen, Junhui; Chi, Daojie
2017-03-01
Solvent extraction organics (SX organics) entrained and dissoluted in the raffinate during copper SX operation, can impact bioleaching in case of raffinate recycling. The influence of SX organics on bioleaching process by Acidithiobacillus ferrooxidans (At. ferrooxidans) has been investigated. The results showed that, cells of At. ferrooxidans grew slower with contaminated low-grade chalcopyrite ores in shaken flasks bioleaching, the copper bioleaching efficiency reached 15%, lower than that of 24% for uncontaminated minerals. Obviously, the SX organics could adsorb on mineral surface and hinder its contact with bacterials, finanlly lead to the low bioleaching efficiency.
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AFM fluid delivery/liquid extraction surface sampling/electrostatic spray cantilever probe
Van Berkel, Gary J.
2015-06-23
An electrospray system comprises a liquid extraction surface sampling probe. The probe comprises a probe body having a liquid inlet and a liquid outlet, and having a liquid extraction tip. A solvent delivery conduit is provided for receiving solvent liquid from the liquid inlet and delivering the solvent liquid to the liquid extraction tip. An open liquid extraction channel extends across an exterior surface of the probe body from the liquid extraction tip to the liquid outlet. An electrospray emitter tip is in liquid communication with the liquid outlet of the liquid extraction surface sampling probe. A system for analyzing samples, a liquid junction surface sampling system, and a method of analyzing samples are also disclosed.
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Marine Sponge-Derived Streptomyces sp. SBT343 Extract Inhibits Staphylococcal Biofilm Formation
Balasubramanian, Srikkanth; Othman, Eman M.; Kampik, Daniel; Stopper, Helga; Hentschel, Ute; Ziebuhr, Wilma; Oelschlaeger, Tobias A.; Abdelmohsen, Usama R.
2017-01-01
Staphylococcus epidermidis and Staphylococcus aureus are opportunistic pathogens that cause nosocomial and chronic biofilm-associated infections. Indwelling medical devices and contact lenses are ideal ecological niches for formation of staphylococcal biofilms. Bacteria within biofilms are known to display reduced susceptibilities to antimicrobials and are protected from the host immune system. High rates of acquired antibiotic resistances in staphylococci and other biofilm-forming bacteria further hamper treatment options and highlight the need for new anti-biofilm strategies. Here, we aimed to evaluate the potential of marine sponge-derived actinomycetes in inhibiting biofilm formation of several strains of S. epidermidis, S. aureus, and Pseudomonas aeruginosa. Results from in vitro biofilm-formation assays, as well as scanning electron and confocal microscopy, revealed that an organic extract derived from the marine sponge-associated bacterium Streptomyces sp. SBT343 significantly inhibited staphylococcal biofilm formation on polystyrene, glass and contact lens surfaces, without affecting bacterial growth. The extract also displayed similar antagonistic effects towards the biofilm formation of other S. epidermidis and S. aureus strains tested but had no inhibitory effects towards Pseudomonas biofilms. Interestingly the extract, at lower effective concentrations, did not exhibit cytotoxic effects on mouse fibroblast, macrophage and human corneal epithelial cell lines. Chemical analysis by High Resolution Fourier Transform Mass Spectrometry (HRMS) of the Streptomyces sp. SBT343 extract proportion revealed its chemical richness and complexity. Preliminary physico-chemical characterization of the extract highlighted the heat-stable and non-proteinaceous nature of the active component(s). The combined data suggest that the Streptomyces sp. SBT343 extract selectively inhibits staphylococcal biofilm formation without interfering with bacterial cell viability. Due to absence of cell toxicity, the extract might represent a good starting material to develop a future remedy to block staphylococcal biofilm formation on contact lenses and thereby to prevent intractable contact lens-mediated ocular infections. PMID:28261188
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Fischer, Horst; Machen, Terry E; Widdicombe, Jonathan H; Carlson, Thomas J S; King, Steven R; Chow, John W S; Illek, Beate
2004-08-01
An oligomeric proanthocyanidin (SP-303) extracted from the bark latex of the tree Croton lechleri (family Euphorbiaceae) is a potent inhibitor of cholera toxin-induced fluid accumulation and chloride secretion. The manufacturing process for SP-303 was optimized and simplified to produce an increased yield of the herbal extract. The novel extract (named SB-300) contained on average 70.6+/-7.2% SP-303 by weight (mean +/- S.D.; n=56 lots). Here, we describe the effectiveness of SB-300 on cAMP-regulated chloride secretion, which is mediated by the cystic fibrosis transmembrane conductance regulator Cl- channel (CFTR) in human colonic T84 cells. Exposure of the apical surface to SB-300 blocked forskolin-stimulated Cl- secretion by 92.2+/-3.0% with a half-maximal inhibition constant (KB) of 4.8+/-0.8 microM. For SP-303, stimulated Cl- currents were decreased by 98.0+/-7.2 % and KB averaged 4.1+/-1.3 microM. There was no significant difference between the blocking kinetics of SP-303 and SB-300. Forskolin-stimulated whole cell Cl- currents were effectively blocked by extracellular addition of SB-300 (63+/-8.5%; n=3) and to a similar extent by SP-303 (83 +/- 0.6%; n=2; at 50 microM each). Both extracts inhibited a time- and voltage-independent Cl- conductance, which indicated the involvement of CFTR Cl- channels. We conclude that both SP-303 (used in Provir) and SB-300 (used in NSF Normal Stool Formula) are novel natural products that target the CFTR Cl- channel. SB-300 is a low cost herbal extract and may present a complementary and alternative medicine approach for the treatment of fluid loss in watery diarrhea.
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Ardlin, Berit I; Lindholm-Sethson, Britta; Dahl, Jon E
2009-02-01
To study corrosion and to evaluate biological effects in vitro of corrosion products of a copper-aluminum-nickel alloy with 2% gold. The alloy NPGtrade mark+2 with the nominal composition Cu:77.3; Al:7.8; Ni:4.3; Fe:3.0; Zn:2.7; Au:2.0; and Mn:1.7 was characterized. Static immersion in acidic saline, pH 2.2-2.4, was used to determine release of metallic elements in a milieu simulating the condition of plaque build-up in interproximal areas of the tooth. Corrosion and surface reactions in saline and artificial saliva were studied by electrochemical techniques including registration of open-circuit-potentials, polarization curves and impedance spectra. Extracts were made in cell culture media and acidic saline and used for MTT test for cytotoxicity and HET-CAM method for irritation. The mean amount of elements released in the acidic saline were in microg cm(-2) : Cu:632; Al:210; Ni:144; Fe:122; Zn:48; Mn:52. No protective film was formed on the surface of the alloy, as extensive corrosion was observed in both saline and artificial saliva. The corrosion rate was higher in saline than in artificial saliva. Acidic extracts of the alloy diluted up to 64 times reduced cell viability with 80% or more. The extract induced coagulation of the blood vessels of the CAM and was rated as moderate irritant solution. The nickel-aluminum bronze showed high corrosion rate caused by an inability to create a protective surface layer. High levels of toxic elements were found after static immersion testing, and the corrosion products had a distinct adverse effect on the biological activity. Copyright 2008 Wiley Periodicals, Inc.
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Heim, Kyle P.; Sullan, Ruby May A.; Crowley, Paula J.; El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Tang, Wenxing; Besingi, Richard; Dufrene, Yves F.; Brady, L. Jeannine
2015-01-01
P1 (antigen I/II) is a sucrose-independent adhesin of Streptococcus mutans whose functional architecture on the cell surface is not fully understood. S. mutans cells subjected to mechanical extraction were significantly diminished in adherence to immobilized salivary agglutinin but remained immunoreactive and were readily aggregated by fluid-phase salivary agglutinin. Bacterial adherence was restored by incubation of postextracted cells with P1 fragments that contain each of the two known adhesive domains. In contrast to untreated cells, glutaraldehyde-treated bacteria gained reactivity with anti-C-terminal monoclonal antibodies (mAbs), whereas epitopes recognized by mAbs against other portions of the molecule were masked. Surface plasmon resonance experiments demonstrated the ability of apical and C-terminal fragments of P1 to interact. Binding of several different anti-P1 mAbs to unfixed cells triggered release of a C-terminal fragment from the bacterial surface, suggesting a novel mechanism of action of certain adherence-inhibiting antibodies. We also used atomic force microscopy-based single molecule force spectroscopy with tips bearing various mAbs to elucidate the spatial organization and orientation of P1 on living bacteria. The similar rupture lengths detected using mAbs against the head and C-terminal regions, which are widely separated in the tertiary structure, suggest a higher order architecture in which these domains are in close proximity on the cell surface. Taken together, our results suggest a supramolecular organization in which additional P1 polypeptides, including the C-terminal segment originally identified as antigen II, associate with covalently attached P1 to form the functional adhesive layer. PMID:25666624
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Heim, Kyle P; Sullan, Ruby May A; Crowley, Paula J; El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Tang, Wenxing; Besingi, Richard; Dufrene, Yves F; Brady, L Jeannine
2015-04-03
P1 (antigen I/II) is a sucrose-independent adhesin of Streptococcus mutans whose functional architecture on the cell surface is not fully understood. S. mutans cells subjected to mechanical extraction were significantly diminished in adherence to immobilized salivary agglutinin but remained immunoreactive and were readily aggregated by fluid-phase salivary agglutinin. Bacterial adherence was restored by incubation of postextracted cells with P1 fragments that contain each of the two known adhesive domains. In contrast to untreated cells, glutaraldehyde-treated bacteria gained reactivity with anti-C-terminal monoclonal antibodies (mAbs), whereas epitopes recognized by mAbs against other portions of the molecule were masked. Surface plasmon resonance experiments demonstrated the ability of apical and C-terminal fragments of P1 to interact. Binding of several different anti-P1 mAbs to unfixed cells triggered release of a C-terminal fragment from the bacterial surface, suggesting a novel mechanism of action of certain adherence-inhibiting antibodies. We also used atomic force microscopy-based single molecule force spectroscopy with tips bearing various mAbs to elucidate the spatial organization and orientation of P1 on living bacteria. The similar rupture lengths detected using mAbs against the head and C-terminal regions, which are widely separated in the tertiary structure, suggest a higher order architecture in which these domains are in close proximity on the cell surface. Taken together, our results suggest a supramolecular organization in which additional P1 polypeptides, including the C-terminal segment originally identified as antigen II, associate with covalently attached P1 to form the functional adhesive layer. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
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Inverted organic electronic and optoelectronic devices
NASA Astrophysics Data System (ADS)
Small, Cephas E.
The research and development of organic electronics for commercial application has received much attention due to the unique properties of organic semiconductors and the potential for low-cost high-throughput manufacturing. For improved large-scale processing compatibility and enhanced device stability, an inverted geometry has been employed for devices such as organic light emitting diodes and organic photovoltaic cells. These improvements are attributed to the added flexibility to incorporate more air-stable materials into the inverted device geometry. However, early work on organic electronic devices with an inverted geometry typically showed reduced device performance compared to devices with a conventional structure. In the case of organic light emitting diodes, inverted devices typically show high operating voltages due to insufficient carrier injection. Here, a method for enhancing hole injection in inverted organic electronic devices is presented. By incorporating an electron accepting interlayer into the inverted device, a substantial enhancement in hole injection efficiency was observed as compared to conventional devices. Through a detailed carrier injection study, it is determined that the injection efficiency enhancements in the inverted devices are due to enhanced charge transfer at the electron acceptor/organic semiconductor interface. A similar situation is observed for organic photovoltaic cells, in which devices with an inverted geometry show limited carrier extraction in early studies. In this work, enhanced carrier extraction is demonstrated for inverted polymer solar cells using a surface-modified ZnO-polymer composite electron-transporting layer. The insulating polymer in the composite layer inhibited aggregation of the ZnO nanoparticles, while the surface-modification of the composite interlayer improved the electronic coupling with the photoactive layer. As a result, inverted polymer solar cells with power conversion efficiencies of over 8% were obtained. To further study carrier extraction in inverted polymer solar cells, the active layer thickness dependence of the efficiency was investigated. For devices with active layer thickness < 200 nm, power conversion efficiencies over 8% was obtained. This result is important for demonstrating improved large-scale processing compatibility. Above 200 nm, significant reduction in cell efficiency were observed. A detailed study of the loss processes that contributed to the reduction in efficiency for thick-film devices are presented.
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Guo, Xuesong; Liu, Junxin; Xiao, Benyi
2014-10-20
Extracellular polymeric substances (EPS) are susceptible to contamination by intracellular substances released during the extraction of EPS owing to the damage caused to microbial cell structures. The damage to cell walls and cell membranes in nine EPS extraction processes of activated sludge was evaluated in this study. The extraction of EPS (including proteins, carbohydrates and DNA) was the highest using the NaOH extraction method and the lowest using formaldehyde extraction. All nine EPS extraction methods in this study resulted in cell wall and membrane damage. The damage to cell walls, evaluated by 2-keto-3-deoxyoctonate (KDO) and N-acetylglucosamine content changes in extracted EPS, was the most significant in the NaOH extraction process. Formaldehyde extraction showed a similar extent of damage to cell walls to those detected in the control method (centrifugation), while those in the formaldehyde-NaOH and cation exchange resin extractions were slightly higher than those detected in the control. N-acetylglucosamine was more suitable than KDO for the evaluation of cell wall damage in the EPS extraction of activated sludge. The damage to cell membranes was characterized by two fluorochromes (propidium iodide and FITC Annexin V) with flow cytometry (FCM) measurement. The highest proportion of membrane-damaged cells was detected in NaOH extraction (26.54% of total cells) while membrane-damaged cells comprised 8.19% of total cells in the control. Copyright © 2014 Elsevier B.V. All rights reserved.
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Binding and Utilization of Human Transferrin by Prevotella nigrescens
Duchesne, Pascale; Grenier, Daniel; Mayrand, Denis
1999-01-01
To survive and multiply within their hosts, pathogens must possess efficient iron-scavenging mechanisms. In the present study, we investigate the capacity of Prevotella nigrescens and Prevotella intermedia to use various sources of iron for growth and characterize the transferrin-binding activity of P. nigrescens. Iron-saturated human transferrin and lactoferrin, but not ferric chloride and the iron-free form of transferrin, could be used as sources of iron by P. nigrescens and P. intermedia. Neither siderophore activity nor ferric reductase activity could be detected in P. nigrescens and P. intermedia. However, both species showed transferrin-binding activity as well as the capacity to proteolytically cleave transferrin. To various extents, all strains of P. nigrescens and P. intermedia tested demonstrated transferrin-binding activity. The activity was heat and protease sensitive. The capacity of P. nigrescens to bind transferrin was decreased when cells were grown in the presence of hemin. Preincubation of bacterial cells with hemin, hemoglobin, lactoferrin, fibrinogen, immunoglobulin G, or laminin did not affect transferrin-binding activity. The transferrin-binding protein could be extracted from the cell surface of P. nigrescens by treatment with a zwitterionic detergent. Subjecting the cell surface extract to affinity chromatography on an agarose-transferrin column revealed that it contained a protein having an estimated molecular mass of 37 kDa and possessing transferrin-binding activity. The transferrin-binding activity of P. nigrescens and P. intermedia may permit the bacteria to obtain iron for survival and growth in periodontal pockets. PMID:9916061
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Hu, Bin; Li, Cheng; Zhang, Zhiqing; Zhao, Qing; Zhu, Yadong; Su, Zhao; Chen, Yizi
2017-09-15
Microwave-assisted extraction (MAE) of oil from silkworm pupae was firstly performed in the present research. The response surface methodology was applied to optimize the parameters for MAE. The yield of oil by MAE was 30.16% under optimal conditions of a mixed solvent consisting of ethanol and n-hexane (1:1, v/v), microwave power (360W), liquid to solid ratio (7.5/1mL/g), microwave time (29min). Moreover, oil extracted by MAE was quantitatively (yield) and qualitatively (fatty acid profile) similar to those obtained using Soxhlet extraction (SE), but oil extracted by MAE exhibited favourable physicochemical properties and oxidation stability. Additionally, oil extracted by MAE had a higher content of total phenolic, and it showed stronger antioxidant activities. Scanning electron microscopy revealed that microwave technique efficiently promoted the release of oil by breaking down the cell structure of silkworm pupae. Therefore, MAE can be an effective method for the silkworm pupal oil extraction. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Characterization of pectic polysaccharides extracted from apple pomace by hot-compressed water.
Wang, Xin; Lü, Xin
2014-02-15
Response surface methodology (RSM) was used to optimize the extraction of pectic polysaccharides from apple pomace by hot-compressed water, by which the optimum levels of the parameters were obtained as follows: extraction temperature 140 °C, extraction time 5 min, S:W ratio 1:14. Compared with commercial pectin, the Mw, galacturonic acid content, DM and protein of the extracted pectic polysaccharides were lower while ash content and neutral sugars were higher. The endothermic transition temperature and fusion heat of the extracted pectic polysaccharides was lower than commercial one according to DSC analysis. For its rheological properties, it was found that the viscosity of the extracted pectic polysaccharides solution was slightly lower than commercial pectin at lower shear rate region while it decreased sharply when the shear rate increased. Besides, both G' and G" moduli of the extracted pectic polysaccharides were lower than the commercial pectin's possibly because of weaker polymer chain interaction, which was also reflected in gel textural properties. However, the extracted pectic polysaccharides showed higher in vitro antioxidant capability and inhibitory effect on HT-29 colon adenocarcinoma cells than commercial pectin. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Huang, Aibin; Lei, Lei; Zhu, Jingting; Yu, Yu; Liu, Yan; Yang, Songwang; Bao, Shanhu; Cao, Xun; Jin, Ping
2017-01-25
The short circuit current density of perovskite solar cell (PSC) was boosted by modulating the dominated plane facets of TiO 2 electron transport layer (ETL). Under optimized condition, TiO 2 with dominant {001} facets showed (i) low incident light loss, (ii) highly smooth surface and excellent wettability for precursor solution, (iii) efficient electron extraction, and (iv) high conductivity in perovskite photovoltaic application. A current density of 24.19 mA cm -2 was achieved as a value near the maximum limit. The power conversion efficiency was improved to 17.25%, which was the record value of PSCs with DC magnetron sputtered carrier transport layer. What is more, the room-temperature process had a great significance for the cost reduction and flexible application of PSCs.
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NASA Astrophysics Data System (ADS)
Ojha, Sunita; Sett, Arghya; Bora, Utpal
2017-09-01
In this study, we report synthesis of silver nanoparticles (RcAgNPs) from silver nitrate solution using methanolic leaf extract of Ricinus communis var. carmencita. The polyphenols present in the leaves reduce Ag++ ions to Ag0 followed by a color change. Silver nanoparticle formation was ensured by surface plasmon resonance between 400 nm to 500 nm. Crystallinity of the synthesized nanoparticles was confirmed by UHRTEM, SAED and XRD analysis. The capping of phytochemicals and thermal stability of RcAgNPs were assessed by FTIR spectra and TGA analysis, respectively. It also showed antibacterial activity against both gram positive and gram negative strains. RcAgNPs were non-toxic against normal cell line (mouse fibroblast cell line L929) at lower concentrations (80 µg ml-1).
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Scotti, Luciana; Scotti, Marcus T; Ishiki, Hamilton; Junior, Francisco J B M; dos, Santos Paula F; Tavares, Josean F; da Silva, Marcelo S
2014-05-01
The aim of this work was to predict the anticancer potential of 3 atisane, and 3 trachylobane diterpene compounds extracted from the roots of Xylopia langsdorffiana. The prediction of anticancer activity as expressed against PC-3 tumor cells was made using a PLS model built with 26 diterpenes in the training set. Significant statistical measures were obtained. The six investigated diterpenes were applied to the model and their activities against PC-3 cells were calculated. All the diterpenes were active, with atisane diterpenes showing the higher pICso values. In human prostate carcinoma PC-3 cells, the apoptosis mechanism is related to an inhibition of IKK/NF-KB. Antioxidant potential implies a greater electronic molecular atmosphere (increased donor electron capacity), which can reduce radical reactivity, and facilitate post donation charge accommodation. Molecular surfaces indicated a much greater electronic cloud over atisane diterpenes.
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Analytical modeling of the temporal evolution of hot spot temperatures in silicon solar cells
NASA Astrophysics Data System (ADS)
Wasmer, Sven; Rajsrima, Narong; Geisemeyer, Ino; Fertig, Fabian; Greulich, Johannes Michael; Rein, Stefan
2018-03-01
We present an approach to predict the equilibrium temperature of hot spots in crystalline silicon solar cells based on the analysis of their temporal evolution right after turning on a reverse bias. For this end, we derive an analytical expression for the time-dependent heat diffusion of a breakdown channel that is assumed to be cylindrical. We validate this by means of thermography imaging of hot spots right after turning on a reverse bias. The expression allows to be used to extract hot spot powers and radii from short-term measurements, targeting application in inline solar cell characterization. The extracted hot spot powers are validated at the hands of long-term dark lock-in thermography imaging. Using a look-up table of expected equilibrium temperatures determined by numerical and analytical simulations, we utilize the determined hot spot properties to predict the equilibrium temperatures of about 100 industrial aluminum back-surface field solar cells and achieve a high correlation coefficient of 0.86 and a mean absolute error of only 3.3 K.
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Arunachalam, Kantha Deivi; Arun, Lilly Baptista; Annamalai, Sathesh Kumar; Arunachalam, Aarrthy M
2015-01-01
Background Gymnema sylvestre is an ethno-pharmacologically important medicinal plant used in many polyherbal formulations for its potential health benefits. Silver nanoparticles (SNPs) were biofunctionalized using aqueous leaf extracts of G. sylvestre. The anticancer properties of the bioactive compounds and the biofunctionalized SNPs were compared using the HT29 human adenoma colon cancer cell line. Methods The preliminary phytochemical screening for bioactive compounds from aqueous extracts revealed the presence of alkaloids, triterpenes, flavonoids, steroids, and saponins. Biofunctionalized SNPs were synthesized using silver nitrate and characterized by ultraviolet–visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, and X-ray diffraction for size and shape. The characterized biofunctionalized G. sylvestre were tested for its in vitro anticancer activity against HT29 human colon adenocarcinoma cells. Results The biofunctionlized G. sylvestre SNPs showed the surface plasmon resonance band at 430 nm. The scanning electron microscopy images showed the presence of spherical nanoparticles of various sizes, which were further determined using the Scherrer equation. In vitro cytotoxic activity of the biofunctionalized green-synthesized SNPs (GSNPs) indicated that the sensitivity of HT29 human colon adenocarcinoma cells for cytotoxic drugs is higher than that of Vero cell line for the same cytotoxic agents and also higher than the bioactive compound of the aqueous extract. Conclusion Our results show that the anticancer properties of the bioactive compounds of G. sylvestre can be enhanced through biofunctionalizing the SNPs using the bioactive compounds present in the plant extract without compromising their medicinal properties. PMID:25565802
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Smolka, Marcus Bustamante; Martins-de-Souza, Daniel; Martins, Daniel; Winck, Flavia Vischi; Santoro, Carlos Eduardo; Castellari, Rafael Ramos; Ferrari, Fernanda; Brum, Itaraju Junior; Galembeck, Eduardo; Della Coletta Filho, Helvécio; Machado, Marcos Antonio; Marangoni, Sergio; Novello, Jose Camillo
2003-02-01
The bacteria Xylella fastidiosa is the causative agent of a number of economically important crop diseases, including citrus variegated chlorosis. Although its complete genome is already sequenced, X. fastidiosa is very poorly characterized by biochemical approaches at the protein level. In an initial effort to characterize protein expression in X. fastidiosa we used one- and two-dimensional gel electrophoresis and mass spectrometry to identify the products of 142 genes present in a whole cell extract and in an extracellular fraction of the citrus isolated strain 9a5c. Of particular interest for the study of pathogenesis are adhesion and secreted proteins. Homologs to proteins from three different adhesion systems (type IV fimbriae, mrk pili and hsf surface fibrils) were found to be coexpressed, the last two being detected only as multimeric complexes in the high molecular weight region of one-dimensional electrophoresis gels. Using a procedure to extract secreted proteins as well as proteins weakly attached to the cell surface we identified 30 different proteins including toxins, adhesion related proteins, antioxidant enzymes, different types of proteases and 16 hypothetical proteins. These data suggest that the intercellular space of X. fastidiosa colonies is a multifunctional microenvironment containing proteins related to in vivo bacterial survival and pathogenesis. A codon usage analysis of the most expressed proteins from the whole cell extract revealed a low biased distribution, which we propose is related to the slow growing nature of X. fastidiosa. A database of the X. fastidiosa proteome was developed and can be accessed via the internet (URL: www.proteome.ibi.unicamp.br).
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The Effect of Detergents on the Morphology and Immunomodulatory Activity of Malassezia furfur.
Kim, Su-Han; Ko, Hyun-Chang; Kim, Moon-Bum; Kwon, Kyung-Sool; Oh, Chang-Keun
2009-05-01
Several workers have found that Malassezia are capable of suppressing cytokine release and downregulating the phagocytic function of monocytes. But lipid-depleted Malassezia furfur (M. furfur) extracts have also been shown to induce increased production of TNF-alpha, IL-6 and IL-1beta in monocytes. We thought that the detergents in shampoos or soaps could change the composition of the lipid in the M. furfur cell wall. We studied whether detergents affect the morphology of M. furfur and if the inflammatory cytokine profiles change in the monocytes treated with detergent-treated M. furfur. Commonly used detergents such as sodium lauryl sulfate, ammonium lauryl sulfate and tween-80 were respectively added to the modified Leeming-Notman's media. M. furfur was cultivated in each media (detergent-added or untreated). Thereafter, the surface morphology of the yeast was evaluated by scanning and transmission electron microscopy. The cytokine profiles of monocytes, which were treated by M. furfur with or without detergents, were also evaluated. The detergent-treated M. furfur were similar to the lipid-extracted form of M. furfur on the electron microscopic study, with a recessed, withered surface and with thinner and rather electron transparent cell walls than the detergent-untreated M. furfur. The levels of TNF-alpha were higher in monocytes treated with detergent-treated Malassezia than that in the monocytes treated with the detergent-untreated Malassezia (p<0.05). According to the findings in this study, it could be inferred that the detergents in shampoos or soaps affect the lipid layers of the Malassezia cell wall and these lipid-extracted Malassezia induce or aggravate some inflammatory conditions. But to correlate the relationship between detergents and Malassezia-associated diseases, in vivo experiments that will focus on short-term contact with detergents in real life conditions should be done.
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NASA Astrophysics Data System (ADS)
Barai, Abir Chandan; Paul, Koushik; Dey, Aditi; Manna, Subhankar; Roy, Somenath; Bag, Braja Gopal; Mukhopadhyay, Chiradeep
2018-04-01
The phytochemicals present in the stem bark extract of Nerium oleander (commonly known as Karabi) have been utilized for the green synthesis of stable gold-conjugated nanoparticles at room temperature under very mild conditions. The green synthesized gold-conjugated nanoparticles were characterized by surface plasmon resonance spectroscopy, High resolution transmission electron microscopy, X-ray diffraction studies and dynamic light scattering. A mechanism for the synthesis and stabilization of gold-conjugated nanoparticles (AuNPs) has been proposed. Anticancer activity of the stabilized AuNPs studied against MCF-7 breast cancer cell line revealed that the stabilized AuNPs were highly effective for the apoptosis of cancer cells selectively. The antioxidant activity of the stem bark extract of Nerium oleander has also been studied against a long lived 2,2-diphenylpicrylhydrazyl radical at room temperature. Moreover, the utilization of the stabilized AuNPs as a catalyst has also been demonstrated. [Figure not available: see fulltext.
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Barai, Abir Chandan; Paul, Koushik; Dey, Aditi; Manna, Subhankar; Roy, Somenath; Bag, Braja Gopal; Mukhopadhyay, Chiradeep
2018-01-01
The phytochemicals present in the stem bark extract of Nerium oleander (commonly known as Karabi) have been utilized for the green synthesis of stable gold-conjugated nanoparticles at room temperature under very mild conditions. The green synthesized gold-conjugated nanoparticles were characterized by surface plasmon resonance spectroscopy, High resolution transmission electron microscopy, X-ray diffraction studies and dynamic light scattering. A mechanism for the synthesis and stabilization of gold-conjugated nanoparticles (AuNPs) has been proposed. Anticancer activity of the stabilized AuNPs studied against MCF-7 breast cancer cell line revealed that the stabilized AuNPs were highly effective for the apoptosis of cancer cells selectively. The antioxidant activity of the stem bark extract of Nerium oleander has also been studied against a long lived 2,2-diphenylpicrylhydrazyl radical at room temperature. Moreover, the utilization of the stabilized AuNPs as a catalyst has also been demonstrated.
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Theansungnoen, Tinnakorn; Maijaroen, Surachai; Jangpromma, Nisachon; Yaraksa, Nualyai; Daduang, Sakda; Temsiripong, Theeranan; Daduang, Jureerut; Klaynongsruang, Sompong
2016-06-01
Known antimicrobial peptides KT2 and RT2 as well as the novel RP9 derived from the leukocyte extract of the freshwater crocodile (Crocodylus siamensis) were used to evaluate the ability in killing human cervical cancer cells. RP9 in the extract was purified by a combination of anion exchange column and reversed-phase HPLC, and its sequence was analyzed by mass spectrometry. The novel peptide could inhibit Gram-negative Vibrio cholerae (clinical isolation) and Gram-positive Bacillus pumilus TISTR 905, and its MIC values were 61.2 µM. From scanning electron microscopy, the peptide was seen to affect bacterial surfaces directly. KT2 and RT2, which are designed antimicrobial peptides using the C. siamensis Leucrocin I template, as well as RP9 were chemically synthesized for investigation of anticancer activity. By Sulforhodamine B colorimetric assay, these antimicrobial peptides could inhibit both HeLa and CaSki cancer cell lines. The IC50 values of KT2 and RT2 for HeLa and CaSki cells showed 28.7-53.4 and 17.3-30.8 µM, while those of RP9 were 126.2 and 168.3 µM, respectively. Additionally, the best candidate peptides KT2 and RT2 were used to determine the apoptotic induction on cancer cells by human apoptosis array assay. As a result, KT2 and RT2 were observed to induce apoptotic cell death in HeLa cells. Therefore, these results indicate that KT2 and RT2 with antimicrobial activity have a highly potent ability to kill human cervical cancer cells.
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Leis, Dorothea; Lauß, Bernhard; Macher-Ambrosch, Robert; Pfennig, Andreas; Nidetzky, Bernd; Kratzer, Regina
2017-09-10
Product isolation from aqueous-organic reaction mixtures that contain high concentrations of whole cells constitutes a challenging task in bioprocessing. Stirring of the biphasic reaction media leads to the formation of solvent droplets coated by cells and other surface active components and an emulsion forms. We used an early focus on phase separation to simplify a whole-cell bioreduction. Octanol, heptanol, hexanol, hexane and dipropylether were tested as co-solvents in the E. coli catalyzed reduction of o-chloroacetophenone. All solvents showed very similar performance in bioreductions and highest yields were obtained with low organic-to-aqueous phase ratios. Reaction mixtures were directly investigated for organic-phase recovery. Phase separation was optimized in small-scale settling experiments and confirmed by the isolation of 20.4g (S)-1-(2-chlorophenyl)ethanol from a 0.5L batch reduction containing 40g CDW /L whole-cell catalyst. Solvent consumption during product isolation could be halved by the simple addition of sodium hydroxide prior to product extraction. Basification to pH 13.5 and three extraction steps with a total of 1.2v/v hexane led to an isolated yield of 87% (97% reduction yield). A general emulsion destabilizing effect under harsh conditions, as extreme pH values and presence of toxic reactants, was observed. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
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Physalis angulata induces in vitro differentiation of murine bone marrow cells into macrophages.
da Silva, Bruno José Martins; Rodrigues, Ana Paula D; Farias, Luis Henrique S; Hage, Amanda Anastácia P; Do Nascimento, Jose Luiz M; Silva, Edilene O
2014-10-03
The bone marrow is a hematopoietic tissue that, in the presence of cytokines and growth factors, generates all of the circulating blood cells. These cells are important for protecting the organism against pathogens and for establishing an effective immune response. Previous studies have shown immunomodulatory effects of different products isolated from plant extracts. This study aimed to evaluate the immunomodulatory properties of aqueous Physalis angulata (AEPa) extract on the differentiation of bone marrow cells. Increased cellular area, higher spreading ability and several cytoplasmatic projections were observed in the treated cells, using optical microscopy, suggesting cell differentiation. Furthermore, AEPa did not promote the proliferation of lymphocytes and polymorphonuclear leukocytes, however promotes increased the number of macrophages in the culture. The ultrastructural analysis by Transmission Electron Microscopy of treated cells showed spreading ability, high number of cytoplasmatic projections and increase of autophagic vacuoles. Moreover, a high level of LC3b expression by treated cells was detected by flow cytometry, suggesting an autophagic process. Cell surface expression of F4/80 and CD11b also indicated that AEPa may stimulate differentiation of bone marrow cells mainly into macrophages. In addition, AEPa did not differentiate cells into dendritic cells, as assessed by CD11c analysis. Furthermore, no cytotoxic effects were observed in the cells treated with AEPa. Results demonstrate that AEPa promotes the differentiation of bone marrow cells, particularly into macrophages and may hold promise as an immunomodulating agent.
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Physalis angulata induces in vitro differentiation of murine bone marrow cells into macrophages
2014-01-01
Background The bone marrow is a hematopoietic tissue that, in the presence of cytokines and growth factors, generates all of the circulating blood cells. These cells are important for protecting the organism against pathogens and for establishing an effective immune response. Previous studies have shown immunomodulatory effects of different products isolated from plant extracts. This study aimed to evaluate the immunomodulatory properties of aqueous Physalis angulata (AEPa) extract on the differentiation of bone marrow cells. Results Increased cellular area, higher spreading ability and several cytoplasmatic projections were observed in the treated cells, using optical microscopy, suggesting cell differentiation. Furthermore, AEPa did not promote the proliferation of lymphocytes and polymorphonuclear leukocytes, however promotes increased the number of macrophages in the culture. The ultrastructural analysis by Transmission Electron Microscopy of treated cells showed spreading ability, high number of cytoplasmatic projections and increase of autophagic vacuoles. Moreover, a high level of LC3b expression by treated cells was detected by flow cytometry, suggesting an autophagic process. Cell surface expression of F4/80 and CD11b also indicated that AEPa may stimulate differentiation of bone marrow cells mainly into macrophages. In addition, AEPa did not differentiate cells into dendritic cells, as assessed by CD11c analysis. Furthermore, no cytotoxic effects were observed in the cells treated with AEPa. Conclusion Results demonstrate that AEPa promotes the differentiation of bone marrow cells, particularly into macrophages and may hold promise as an immunomodulating agent. PMID:25281406
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Xiao, Z; Devreotes, P N
1997-01-01
Unlike most other cellular proteins, the chemoattractant receptor, cAR1, of Dictyostelium is resistant to extraction by the zwitterionic detergent, CHAPS. We exploited this property to isolate a subcellular fraction highly enriched in cAR1 by flotation of CHAPS lysates of cells in sucrose density gradients. Immunogold electron microscopy studies revealed a homogeneous preparation of membrane bilayer sheets. This preparation, designated CHAPS-insoluble floating fraction (CHIEF), also contained a defined set of 20 other proteins and a single uncharged lipid. Cell surface biotinylation and preembedding immunoelectron microscopy both confirmed the plasma membrane origin of this preparation. The cell surface phosphodiesterase (PDE) and a downstream effector of cAR1, adenylate cyclase (ACA), were specifically localized in these structures, whereas the cell adhesion molecule gp80, most of the major cell surface membrane proteins, cytoskeletal components, the actin-binding integral membrane protein ponticulin, and G-protein alpha- and beta-subunits were absent. Overall, CHIFF represents about 3-5% of cell externally exposed membrane proteins. All of these results indicate that CHIFF is derived from specialized microdomains of the plasma membrane. The method of isolation is analogous to that of caveolae. However, we were unable to detect distinct caveolae-like structures on the cell surface associated with cAR1, which showed a diffuse staining profile. The discovery of CHIFF facilitates the purification of cAR1 and related signaling proteins and the biochemical characterization of receptor-mediated processes such as G-protein activation and desensitization. It also has important implications for the "fluid mosaic" model of the plasma membrane structures. Images PMID:9168471
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Xiao, Z; Devreotes, P N
1997-05-01
Unlike most other cellular proteins, the chemoattractant receptor, cAR1, of Dictyostelium is resistant to extraction by the zwitterionic detergent, CHAPS. We exploited this property to isolate a subcellular fraction highly enriched in cAR1 by flotation of CHAPS lysates of cells in sucrose density gradients. Immunogold electron microscopy studies revealed a homogeneous preparation of membrane bilayer sheets. This preparation, designated CHAPS-insoluble floating fraction (CHIEF), also contained a defined set of 20 other proteins and a single uncharged lipid. Cell surface biotinylation and preembedding immunoelectron microscopy both confirmed the plasma membrane origin of this preparation. The cell surface phosphodiesterase (PDE) and a downstream effector of cAR1, adenylate cyclase (ACA), were specifically localized in these structures, whereas the cell adhesion molecule gp80, most of the major cell surface membrane proteins, cytoskeletal components, the actin-binding integral membrane protein ponticulin, and G-protein alpha- and beta-subunits were absent. Overall, CHIFF represents about 3-5% of cell externally exposed membrane proteins. All of these results indicate that CHIFF is derived from specialized microdomains of the plasma membrane. The method of isolation is analogous to that of caveolae. However, we were unable to detect distinct caveolae-like structures on the cell surface associated with cAR1, which showed a diffuse staining profile. The discovery of CHIFF facilitates the purification of cAR1 and related signaling proteins and the biochemical characterization of receptor-mediated processes such as G-protein activation and desensitization. It also has important implications for the "fluid mosaic" model of the plasma membrane structures.
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Aguirre, Ana-Maria; Bassi, Amarjeet
2013-08-01
The microalgae Chlorella vulgaris produce lipids that after extraction from cells can be converted into biodiesel. However, these lipids cannot be efficiently extracted from cells due to the presence of the microalgae cell wall, which acts as a barrier for lipid removal when traditional extraction methods are employed. Therefore, a microalgae system with high lipid productivity and thinner cell walls could be more suitable for lipid production from microalgae. This study addresses the effect of culture conditions, specifically carbon dioxide and sodium nitrate concentrations, on biomass concentration and the ratio of lipid productivity/cellulose content. Optimization of culture conditions was done by response surface methodology. The empirical model for biomass concentration (R(2) = 96.0%) led to a predicted maximum of 1123.2 mg dw L(-1) when carbon dioxide and sodium nitrate concentrations were 2.33% (v/v) and 5.77 mM, respectively. For lipid productivity/cellulose content ratio (R(2) = 95.2%) the maximum predicted value was 0.46 (mg lipid L(-1) day(-1) )(mg cellulose mg biomass(-1) )(-1) when carbon dioxide concentration was 4.02% (v/v) and sodium nitrate concentration was 3.21 mM. A common optimum point for both variables (biomass concentration and lipid productivity/cellulose content ratio) was also found, predicting a biomass concentration of 1119.7 mg dw L(-1) and lipid productivity/cellulose content ratio of 0.44 (mg lipid L(-1) day(-1) )(mg cellulose mg biomass(-1) )(-1) for culture conditions of 3.77% (v/v) carbon dioxide and 4.01 mM sodium nitrate. The models were experimentally validated and results supported their accuracy. This study shows that it is possible to improve lipid productivity/cellulose content by manipulation of culture conditions, which may be applicable to any scale of bioreactors. Copyright © 2013 Wiley Periodicals, Inc.
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Planar digital nanoliter dispensing system based on thermocapillary actuation.
Darhuber, Anton A; Valentino, Joseph P; Troian, Sandra M
2010-04-21
We provide guidelines for the design and operation of a planar digital nanodispensing system based on thermocapillary actuation. Thin metallic microheaters embedded within a chemically patterned glass substrate are electronically activated to generate and control 2D surface temperature distributions which either arrest or trigger liquid flow and droplet formation on demand. This flow control is a consequence of the variation of a liquid's surface tension with temperature, which is used to draw liquid toward cooler regions of the supporting substrate. A liquid sample consisting of several microliters is placed on a flat rectangular supply cell defined by chemical patterning. Thermocapillary switches are then activated to extract a slender fluid filament from the cell and to divide the filament into an array of droplets whose position and volume are digitally controlled. Experimental results for the power required to extract a filament and to divide it into two or more droplets as a function of geometric and operating parameters are in excellent agreement with hydrodynamic simulations. The capability to dispense ultralow volumes onto a 2D substrate extends the functionality of microfluidic devices based on thermocapillary actuation previously shown effective in routing and mixing nanoliter liquid samples on glass or silicon substrates.
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Harnessing surface plasmons for solar energy conversion
NASA Technical Reports Server (NTRS)
Anderson, L. M.
1983-01-01
NASA research on the feasibility of solar-energy conversion using surface plasmons is reviewed, with a focus on inelastic-tunnel-diode techniques for power extraction. The need for more efficient solar converters for planned space missions is indicated, and it is shown that a device with 50-percent efficiency could cost up to 40 times as much per sq cm as current Si cells and still be competitive. The parallel-processing approach using broadband carriers and tunable diodes is explained, and the physics of surface plasmons on metal surfaces is outlined. Technical problems being addressed include phase-matching sunlight to surface plasmons, minimizing ohmic losses and reradiation in energy transport, coupling into the tunnels by mode conversion, and gaining an understanding of the tunnel-diode energy-conversion process. Diagrams illustrating the design concepts are provided.
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Gadelha, Ana Paula Rocha; Benchimol, Marlene; de Souza, Wanderley
2015-06-01
Giardia intestinalis presents a complex microtubular cytoskeleton formed by specialized structures, such as the adhesive disk, four pairs of flagella, the funis and the median body. The ultrastructural organization of the Giardia cytoskeleton has been analyzed using different microscopic techniques, including high-resolution scanning electron microscopy. Recent advances in scanning microscopy technology have opened a new venue for the characterization of cellular structures and include scanning probe microscopy techniques such as ultra-high-resolution scanning electron microscopy (UHRSEM) and helium ion microscopy (HIM). Here, we studied the organization of the cytoskeleton of G. intestinalis trophozoites using UHRSEM and HIM in membrane-extracted cells. The results revealed a number of new cytoskeletal elements associated with the lateral crest and the dorsal surface of the parasite. The fine structure of the banded collar was also observed. The marginal plates were seen linked to a network of filaments, which were continuous with filaments parallel to the main cell axis. Cytoplasmic filaments that supported the internal structures were seen by the first time. Using anti-actin antibody, we observed a labeling in these filamentous structures. Taken together, these data revealed new surface characteristics of the cytoskeleton of G. intestinalis and may contribute to an improved understanding of the structural organization of trophozoites. Copyright © 2015 Elsevier Inc. All rights reserved.
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Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants.
Alves, Celha Borges Costa; Segurado, Márcio Nunes; Dorta, Miriam Cristina Leandro; Dias, Fátima Ribeiro; Lenza, Maurício Guilherme; Lenza, Marcos Augusto
2016-01-01
To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic.
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Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants
Alves, Celha Borges Costa; Segurado, Márcio Nunes; Dorta, Miriam Cristina Leandro; Dias, Fátima Ribeiro; Lenza, Maurício Guilherme; Lenza, Marcos Augusto
2016-01-01
ABSTRACT Objective: To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. Methods: Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. Results: No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. Conclusion: Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic. PMID:27901227
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NASA Astrophysics Data System (ADS)
Gnana Selvi, B. Clara; Madhavan, J.; Santhanam, Amutha
2016-09-01
In recent years researchers were attracted towards marine sources due to the presence of active components in it. Seaweeds were widely used in pharmaceutical research for their known biological activities. The biological synthesis method of silver nanoparticles (AgNPs) using Padina tetrastromatica seaweed extract and their cytotoxicity against breast cancer MCF-7 cells was reported in this study. The synthesized AgNPs using seaweed extract were subjected to x-ray diffraction, UV-visible spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscope, energy dispersive x-ray, zeta potential to elucidate the structural, morphology, size as well as surface potential parameters. An absorption peak at 430 nm in UV-visible spectrum reveals the excitation and surface plasmon resonance of AgNPs. FE-SEM micrographs exhibits the biosynthesized AgNPs, which are pre-dominantly round shaped and the size ranges between 40-50 nm. The zeta potential value of -27.6 mV confirms the stable nature of biosynthesized silver nanoparticles. Furthermore, the biological synthesized Ag NPs exhibited a dose-dependent cytotoxicity against human breast cancer cell (MCF-7) and the inhibitory concentration (IC50) was found for AgNPs against MCF-7 at 24 h incubation. Biological method of synthesizing silver nanoparticles shows a environmental friendly property which helps in effective electrifying usage in many fields.
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Organic light emitting diode with light extracting layer
Lu, Songwei
2016-06-14
A light extraction substrate includes a glass substrate having a first surface and a second surface. A light extraction layer is formed on at least one of the surfaces. The light extraction layer is a coating, such as a silicon-containing coating, incorporating nanoparticles.
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Quantum dots as strain- and metabolism-specific microbiological labels
NASA Technical Reports Server (NTRS)
Kloepfer, J. A.; Mielke, R. E.; Wong, M. S.; Nealson, K. H.; Stucky, G.; Nadeau, J. L.
2003-01-01
Biologically conjugated quantum dots (QDs) have shown great promise as multiwavelength fluorescent labels for on-chip bioassays and eukaryotic cells. However, use of these photoluminescent nanocrystals in bacteria has not previously been reported, and their large size (3 to 10 nm) makes it unclear whether they inhibit bacterial recognition of attached molecules and whether they are able to pass through bacterial cell walls. Here we describe the use of conjugated CdSe QDs for strain- and metabolism-specific microbial labeling in a wide variety of bacteria and fungi, and our analysis was geared toward using receptors for a conjugated biomolecule that are present and active on the organism's surface. While cell surface molecules, such as glycoproteins, make excellent targets for conjugated QDs, internal labeling is inconsistent and leads to large spectral shifts compared with the original fluorescence, suggesting that there is breakup or dissolution of the QDs. Transmission electron microscopy of whole mounts and thin sections confirmed that bacteria are able to extract Cd and Se from QDs in a fashion dependent upon the QD surface conjugate.
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Stanislawski, Larry V.; Survila, Kornelijus; Wendel, Jeffrey; Liu, Yan; Buttenfield, Barbara P.
2018-01-01
This paper describes a workflow for automating the extraction of elevation-derived stream lines using open source tools with parallel computing support and testing the effectiveness of procedures in various terrain conditions within the conterminous United States. Drainage networks are extracted from the US Geological Survey 1/3 arc-second 3D Elevation Program elevation data having a nominal cell size of 10 m. This research demonstrates the utility of open source tools with parallel computing support for extracting connected drainage network patterns and handling depressions in 30 subbasins distributed across humid, dry, and transitional climate regions and in terrain conditions exhibiting a range of slopes. Special attention is given to low-slope terrain, where network connectivity is preserved by generating synthetic stream channels through lake and waterbody polygons. Conflation analysis compares the extracted streams with a 1:24,000-scale National Hydrography Dataset flowline network and shows that similarities are greatest for second- and higher-order tributaries.
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Analytical and numerical studies of positive ion beam expansion for surface treatment applications
NASA Astrophysics Data System (ADS)
Lounes-Mahloul, Soumya; Bendib, Abderrezeg; Oudini, Noureddine
2018-01-01
The aim of this work is to study the expansion in vacuum, of a positive ion beam with the use of one dimensional (1D) analytic model and a two dimensional Particle-In-Cell (2D-PIC) simulation. The ion beam is extracted and accelerated from preformed plasma by an extraction system composed of two polarized parallel perforated grids. The results obtained with both approaches reveal the presence of a potential barrier downstream the extraction system which tends to reflect the ion flux. The dependence of the critical distance for which all extracted ions are reflected, is investigated as a function of the extracted ion beam current density. In particular, it is shown that the 1D model recovers the well-known Child-Langmuir law and that the 2D simulation presents a significant discrepancy with respect to the 1D prediction. Indeed, for a given value of current density, the transverse effects lead to a greater critical distance.
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NASA Astrophysics Data System (ADS)
Toušek, J.; Toušková, J.; Remeš, Z.; Chomutová, R.; Čermák, J.; Helgesen, M.; Carlé, J. E.; Krebs, F. C.
2015-12-01
Measurements of electrical conductivity, electron work function, carrier mobility of holes and the diffusion length of excitons were performed on samples of conjugated polymers relevant to polymer solar cells. A state of the art fluorinated benzothiadiazole based conjugated copolymer (PBDTTHD - DTBTff) was studied and benchmarked against the reference polymer poly-3-hexylthiophene (P3HT). We employed, respectively, four electrode conductivity measurements, Kelvin probe work function measurements, carrier mobility using charge extraction by linearly increasing voltage (CELIV) measurements and diffusion length determinaton using surface photovoltage measurements.
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Efficient Planar Perovskite Solar Cells Using Passivated Tin Oxide as an Electron Transport Layer.
Lee, Yonghui; Lee, Seunghwan; Seo, Gabseok; Paek, Sanghyun; Cho, Kyung Taek; Huckaba, Aron J; Calizzi, Marco; Choi, Dong-Won; Park, Jin-Seong; Lee, Dongwook; Lee, Hyo Joong; Asiri, Abdullah M; Nazeeruddin, Mohammad Khaja
2018-06-01
Planar perovskite solar cells using low-temperature atomic layer deposition (ALD) of the SnO 2 electron transporting layer (ETL), with excellent electron extraction and hole-blocking ability, offer significant advantages compared with high-temperature deposition methods. The optical, chemical, and electrical properties of the ALD SnO 2 layer and its influence on the device performance are investigated. It is found that surface passivation of SnO 2 is essential to reduce charge recombination at the perovskite and ETL interface and show that the fabricated planar perovskite solar cells exhibit high reproducibility, stability, and power conversion efficiency of 20%.
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NASA Technical Reports Server (NTRS)
Miyamoto, Yuko J.; Mitchell, Jason S.; McIntyre, Bradley W.
2003-01-01
CD98 is a cell surface protein previously characterized as a cell activation marker, an amino acid transporter, and has recently been implicated in integrin-related functions. Integrins are cell surface proteins, important for homotypic cell aggregation, cell adhesion, and coactivation of T lymphocytes. We have previously shown that the anti-CD98 mAb 80A10, when coimmobilized with anti-CD3 mAb OKT3, is able to mediate human T cell coactivation that is inhibited by anti-beta1 integrin specific mAb 18D3. These results indicated a functional association of CD98 and beta1 integrin signaling but left open the question of a physical association. We now show the induction of homotypic aggregation through CD98 among human T cells and this aggregation was inhibited by anti-beta1 integrin mAb. Therefore, CD98-dependent lymphocyte proliferation and adhesion may involve integrins. Competitive binding assays and fluorescence colocalization analysis suggested that CD98 and beta1 integrin were physically associated. Differential extraction techniques and immunoprecipitations provided the first evidence that the alpha4beta1 integrin and CD98 are specifically associated on human T lymphocytes.
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de Faria, Janaína T; Rocha, Pollyana F; Converti, Attilio; Passos, Flávia M L; Minim, Luis A; Sampaio, Fábio C
2013-12-01
The aim of our study was to select the optimal operating conditions to permeabilize Kluyveromyces lactis cells using ethanol as a solvent as an alternative to cell disruption and extraction. Cell permeabilization was carried out by a non-mechanical method consisting of chemical treatment with ethanol, and the results were expressed as β-galactosidase activity. Experiments were conducted under different conditions of ethanol concentration, treatment time and temperature according to a central composite rotatable design (CCRD), and the collected results were then worked out by response surface methodology (RSM). Cell permeabilization was improved by an increase in ethanol concentration and simultaneous decreases in the incubation temperature and treatment time. Such an approach allowed us to identify an optimal range of the independent variables within which the β-galactosidase activity was optimized. A maximum permeabilization of 2,816 mmol L(-1) oNP min(-1) g(-1) was obtained by treating cells with 75.0% v/v of ethanol at 20.0 °C for 15.0 min. The proposed methodology resulted to be effective and suited for K. lactis cells permeabilization at a lab-scale and promises to be of possible interest for future applications mainly in the food industry.
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Tulsani, Srikanth Reddy; Rath, Arup Kumar
2018-07-15
The solution-processed quantum dot (QD) solar cell technology has seen significant advancements in recent past to emerge as a potential contender for the next generation photovoltaic technology. In the development of high performance QD solar cell, the surface ligand chemistry has played the important role in controlling the doping type and doping density of QD solids. For instance, lead sulfide (PbS) QDs which is at the forefront of QD solar cell technology, can be made n-type or p-type respectively by using iodine or thiol as the surfactant. The advancements in surface ligand chemistry enable the formation of p-n homojunction of PbS QDs layers to attain high solar cell performances. It is shown here, however, that poor Fermi level alignment of thiol passivated p-type PbS QD hole transport layer with the n-type PbS QD light absorbing layer has rendered the photovoltaic devices from realizing their full potential. Here we develop a control surface oxidation technique using facile ultraviolet ozone treatment to increase the p-doping density in a controlled fashion for the thiol passivated PbS QD layer. This subtle surface modification tunes the Fermi energy level of the hole transport layer to deeper values to facilitate the carrier extraction and voltage generation in photovoltaic devices. In photovoltaic devices, the ultraviolet ozone treatment resulted in the average gain of 18% in the power conversion efficiency with the highest recorded efficiency of 8.98%. Copyright © 2018 Elsevier Inc. All rights reserved.
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Trentin, Danielle da Silva; Giordani, Raquel Brandt; Zimmer, Karine Rigon; da Silva, Alexandre Gomes; da Silva, Márcia Vanusa; Correia, Maria Tereza Dos Santos; Baumvol, Israel Jacob Rabin; Macedo, Alexandre José
2011-09-01
Medicinal plants from the Caatinga, a Brazilian xeric shrubland, are used in folk medicine to treat infections. These ethnopharmacological data can contribute to obtaining new antimicrobial/antibiofilm extracts and natural product prototypes for the development of new drugs. The aim of this study was to investigate the antibiofilm and antibacterial activities of 45 aqueous extracts from 24 Caatinga plant species. The effect of aqueous extracts on planktonic cells and on biofilm formation by Staphylococcus epidermidis was studied by the OD(600) absorbance and by the crystal violet assay, respectively. Scanning electron microscopy (SEM) was used to generate comparative images of extract-treated and untreated biofilms. Chromatographic analyses were performed to characterize the active extracts. The in vitro screening, at 0.4 mg/mL and 4.0mg/mL, showed 20 plants effective in preventing biofilm formation and 13 plants able to inhibit planktonic bacterial growth. SEM images demonstrated distinct profiles of bacterial adhesion, matrix production and cell morphology according to different treatments and surfaces. The phytochemical analysis of the selected active extracts indicates the polyphenols, coumarins, steroids and terpenes as possible active compounds. This study describes the first antibiofilm and antibacterial screening of Caatinga plants against S. epidermidis. The evaluation presented in this study confirms several ethnopharmacological reports and can be utilized to identify new antibiofilm and antibacterial products against S. epidermidis from traditional Brazilian medicine. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
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Matić, Ivana Z; Aljancić, Ivana; Vajs, Vlatka; Jadranin, Milka; Gligorijević, Nevenka; Milosavljević, Slobodan; Juranić, Zorica D
2013-09-01
Helichrysum zivojinii Cernjavski & Soska is an endemic plant species that grows in the National Park Galicica in Macedonia. Five extracts were isolated as fractions from the aerial parts of the plant: a n-hexane extract (1), a dichloromethane extract (2), an ethyl-acetate extract (3), a n-butanol extract (4) and a methanol extract (5). A dose-dependent cytotoxic activity of the extracts on MDA-MB-231 and EA.hy926 cells was observed. Extracts exhibited more pronounced cytotoxic actions on MDA-MB-231 cells than on EA.hy926 cells. The n-hexane extract (1), at a non-toxic concentration, exhibited an inhibitory effect on the migration as well the invasiveness of MDA-MB-231 cells. The dichloromethane extract (2), at a non-toxic concentration, demonstrated inhibition of MDA-MB-231 cells invasion. Each of the five extracts applied at non-toxic concentrations inhibited migration of EA.hy926 cells. The prominent inhibitory effect of the n-hexane extract on EA.hy926 cells migration was associated with a notable anti-angiogenic action of this extract. The other four tested extracts demonstrated mild anti-angiogenic activity. Our data highlight the prominent anticancer potential of n-hexane (1) and dichloromethane (2) extracts, which could be attributed to their very pronounced and selective cytotoxic activities as well as their anti-invasive and anti-angiogenic properties.
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NASA Astrophysics Data System (ADS)
Coman, Cristina; Leopold, Loredana Florina; Rugină, Olivia Dumitriţa; Barbu-Tudoran, Lucian; Leopold, Nicolae; Tofană, Maria; Socaciu, Carmen
2014-01-01
A green synthesis was used for preparing stable colloidal gold nanoparticles by using Allium sativum aqueous extract both as reducing and capping agent. The obtained nanoparticles were characterized by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy. Moreover, their potential to be used as surface-enhanced Raman scattering (SERS) substrate was investigated. The obtained gold nanoparticles have spherical shape with mean diameters of 9-15 nm (depending on the amount of reducing agent used under boiling conditions) and are stable up to several months. FTIR spectroscopy shows that the nanoparticles are capped by protein molecules from the extract. The protein shell offers a protective coating, relatively impervious to external molecules, thus, rendering the nanoparticles stable and quite inert. These nanoparticles have the potential to be used as SERS substrates, both in solution and inside human fetal lung fibroblast HFL-1 living cells. We were able to demonstrate both the internalization of the nanoparticles inside HFL-1 cells and their ability to preserve the SERS signal after cellular internalization.
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Khmyrova, Irina; Watanabe, Norikazu; Kholopova, Julia; Kovalchuk, Anatoly; Shapoval, Sergei
2014-07-20
We develop an analytical and numerical model for performing simulation of light extraction through the planar output interface of the light-emitting diodes (LEDs) with nonuniform current injection. Spatial nonuniformity of injected current is a peculiar feature of the LEDs in which top metal electrode is patterned as a mesh in order to enhance the output power of light extracted through the top surface. Basic features of the model are the bi-plane computation domain, related to other areas of numerical grid (NG) cells in these two planes, representation of light-generating layer by an ensemble of point light sources, numerical "collection" of light photons from the area limited by acceptance circle and adjustment of NG-cell areas in the computation procedure by the angle-tuned aperture function. The developed model and procedure are used to simulate spatial distributions of the output optical power as well as the total output power at different mesh pitches. The proposed model and simulation strategy can be very efficient in evaluation of the output optical performance of LEDs with periodical or symmetrical configuration of the electrodes.
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Rapid cell separation with minimal manipulation for autologous cell therapies
NASA Astrophysics Data System (ADS)
Smith, Alban J.; O'Rorke, Richard D.; Kale, Akshay; Rimsa, Roberts; Tomlinson, Matthew J.; Kirkham, Jennifer; Davies, A. Giles; Wälti, Christoph; Wood, Christopher D.
2017-02-01
The ability to isolate specific, viable cell populations from mixed ensembles with minimal manipulation and within intra-operative time would provide significant advantages for autologous, cell-based therapies in regenerative medicine. Current cell-enrichment technologies are either slow, lack specificity and/or require labelling. Thus a rapid, label-free separation technology that does not affect cell functionality, viability or phenotype is highly desirable. Here, we demonstrate separation of viable from non-viable human stromal cells using remote dielectrophoresis, in which an electric field is coupled into a microfluidic channel using shear-horizontal surface acoustic waves, producing an array of virtual electrodes within the channel. This allows high-throughput dielectrophoretic cell separation in high conductivity, physiological-like fluids, overcoming the limitations of conventional dielectrophoresis. We demonstrate viable/non-viable separation efficacy of >98% in pre-purified mesenchymal stromal cells, extracted from human dental pulp, with no adverse effects on cell viability, or on their subsequent osteogenic capabilities.
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NASA Astrophysics Data System (ADS)
Xu, S.; Walczak, J. J.; Wang, L.; Bardy, S. L.; Li, J.
2010-12-01
In this research, we investigate the effects of starvation on the transport of E. coli K12 in saturated porous media. Particularly, we examine the relationship between such effects and the pH and ionic strength of the electrolyte solutions that were used to suspend bacterial cells. E. coli K12 (ATCC 10798) cells were cultured using either Luria-Bertani Miller (LB-Miller) broth (10 g trypton, 5 g yeast extract and 10 g NaCl in 1 L of deionized water) or LB-Luria broth (10 g tryptone, 5 g yeast extract and 0.5 g NaCl in 1 L of deionized water). Both broths had similar pH (~7.1) but differed in ionic strength (LB-Miller: ~170 mM, LB-Luria: ~ 8 mM). The bacterial cells were then harvested and suspended using one of the following electrolyte solutions: phosphate buffered saline (PBS) (pH ~7.2; ionic strength ~170 mM), 168 mM NaCl (pH ~5.7), 5% of PBS (pH ~ 7.2; ionic strength ~ 8 mM) and 8 mM NaCl (pH ~ 5.7). Column transport experiments were performed at 0, 21 and 48 hours following cell harvesting to evaluate the change in cell mobility over time under “starvation” conditions. Our results showed that 1) starvation increased the mobility of E. coli K12 cells; 2) the most significant change in mobility occurred when bacterial cells were suspended in an electrolyte solution that had different pH and ionic strength (i.e., LB-Miller culture suspended in 8 mM NaCl and LB-Luria culture suspended in 168 mM Nacl); and 3) the change in cell mobility primarily occurred within the first 21 hours. The size of the bacterial cells was measured and the surface properties (e.g., zeta potential, hydrophobicity, cell-bound protein, LPS sugar content, outer membrane protein profiles) of the bacterial cells were characterized. We found that the measured cell surface properties could not fully explain the observed changes in cell mobility caused by starvation.
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DeMarini, David M; Warren, Sarah H; Lavrich, Katelyn; Flen, Alexis; Aurell, Johanna; Mitchell, William; Greenwell, Dale; Preston, William; Schmid, Judith E; Linak, William P; Hays, Michael D; Samet, James M; Gullett, Brian K
2017-04-01
Emissions from oil fires associated with the "Deepwater Horizon" explosion and oil discharge that began on April 20, 2010 in the Gulf of Mexico were analyzed chemically to only a limited extent at the time but were shown to induce oxidative damage in vitro and in mice. To extend this work, we burned oil floating on sea water and performed extensive chemical analyses of the emissions (Gullett et al., Marine Pollut Bull, in press, ). Here, we examine the ability of a dichloromethane extract of the particulate material with an aerodynamic size ≤ 2.5 µm (PM 2.5 ) from those emissions to induce oxidative damage in human lung cells in vitro and mutagenicity in 6 strains of Salmonella. The extract had a percentage of extractable organic material (EOM) of 7.0% and increased expression of the heme oxygenase (HMOX1) gene in BEAS-2B cells after exposure for 4 hr at 20 µg of EOM/ml. However, the extract did not alter mitochondrial respiration rate as measured by extracellular flux analysis. The extract was most mutagenic in TA100 +S9, indicative of a role for polycyclic aromatic hydrocarbons (PAHs), reflective of the high concentrations of PAHs in the emissions (1 g/kg of oil consumed). The extract had a mutagenicity emission factor of 1.8 ± 0.1 × 10 5 revertants/megajoule thermal in TA98 +S9, which was greater than that of diesel exhaust and within an order of magnitude of open burning of wood and plastic. Thus, organics from PM 2.5 of burning oil can induce oxidative responses in human airway epithelial cells and are highly mutagenic. Environ. Mol. Mutagen. 58:162-171, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
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Kobayashi, Akemi; Hachiya, Akira; Ohuchi, Atsushi; Kitahara, Takashi; Takema, Yoshinori
2002-02-01
It is known that expression of endothelin-1 (ET-1) increases in the epidermis after UVB irradiation, and that this plays an important role during the induction of pigmentation both as a mitogen and as a melanogen for normal human melanocytes (NHMC). When ET-1 acts on NHMC via the endothelin B receptor (ET(B)R) on their cell surface, mobilization of intracellular calcium is induced, which is followed by activation of Raf-1 located upstream of mitogen activated protein kinase (MAPK). We have continued the search for new agent which inhibit this calcium mobilization and we have found that an extract of Althaea officinalis L. has such an action. In this study, we investigated the precise inhibitory mechanism of this botanical extract on the ET-1-induced activation of melanocytes. Treatment of NHMC with this extract abrogated the stimulatory effect of ET-1 on proliferation and also on activation of MAPK in the intracellular signal transduction pathway, but did not affect the binding of ET-1 to the ET(B)R or the production of Inositol 1,4,5-Trisphosphate (IP3). Further, when this extract was used to treat normal human keratinocytes (NHKC), secretion of ET-1 by those cells was reduced. Taken together, these findings indicate that an extract of A. officinalis inhibits both the secretion of ET-1 from NHKC and the action of ET-1 on NHMC mainly by suppressing the ET-1-induced calcium mobilization without the modification of IP3 production, which in turn suggests that this extract is a useful ingredient for a whitening agent.
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Lee, Yonghun; Kim, Dong-Min; Li, Zhenglin; Kim, Dong-Eun; Kim, Sung-Jin
2018-03-13
We demonstrate a microfiltration chip that separates blood plasma by using water-head-driven pulsatile pressures rather than any external equipment and use it for on-chip amplification of nucleic acids. The chip generates pulsatile pressures to significantly reduce filter clogging without hemolysis, and consists of an oscillator, a plasma-extraction pump, and filter units. The oscillator autonomously converts constant water-head pressure to pulsatile pressure, and the pump uses the pulsatile pressure to extract plasma through the filter. Because the pulsatile pressure can periodically clear blood cells from the filter surface, filter clogging can be effectively reduced. In this way, we achieve plasma extraction with 100% purity and 90% plasma recovery at 15% hematocrit. During a 10 min period, the volume of plasma extracted was 43 μL out of a 243 μL extraction volume at 15% hematocrit. We also studied the influence of the pore size and diameter of the filter, blood loading volume, oscillation period, and hematocrit level on the filtration performance. To demonstrate the utility of our chip for point-of-care testing (POCT) applications, we successfully implemented on-chip amplification of a nucleic acid (miDNA21) in plasma filtered from blood. We expect our chip to be useful not only for POCT applications but also for other bench-top analysis tools using blood plasma.
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Evaluation of Widely Consumed Botanicals as Immunological Adjuvants
Ragupathi, Govind; Hood, Chandra; Yeung, K. Simon; Vickers, Andrew; Hood, Chandra; Deng, Gary; Cheung, Nai-Kong; Vickers, Andrew; Cassileth, Barrie; Livingston, Philip
2008-01-01
Background Many widely used botanical medicines are claimed to be immune enhancers. Clear evidence of augmentation of immune responses in vivo is lacking in most cases. To select botanicals for further study based on immune enhancing activity, we study them here mixed with antigen and injected subcutaneously (s.c.). Globo H and GD3 are cell surface carbohydrates expressed on glycolipids or glycoproteins on the cell surface of many cancers. When conjugated to keyhole limpet hemocyanin (KLH), mixed with an immunological adjuvant and administered s.c. the magnitude of the antibody responses against globo H, GD3 and KLH depend largely on the potency of the adjuvant. We describe here the results obtained using this s.c. immunization model with 7 botanicals purported to have immune stimulant effects. Methods Groups of 5–10 mice were immunized with globo H–KLH or GD3-KLH mixed with botanical, saline or positive control immunological adjuvant, s.c. 3 times at 1 week intervals. Antibody responses were measured 1 and 2 weeks after the 3rd immunization. The following seven botanicals and fractions were tested: (1) H-48 (Honso USA Co.), (2) Coriolus vesicolor raw water extract, purified polysaccharide-K (PSK) or purified polysaccharide-peptide (PSP) (Institute of Chinese Medicine (ICM)), (3) Maitake extract (Yukiguni Maitake Co Ltd. and Tradeworks Group), (4) Echinacea lipophilic, neutral and acidic extracts (Gaia Herbs), (5) Astragalus water, 50% or 95% ethanol extracts (ICM), (6) Turmeric supercritical (SC) or hydro-ethanolic (HE) extracts (New Chapter) or 60% ethanol extract (ICM) and (7) yeast β-glucan (Biotec Pharmacon). Purified saponin extract QS-21 (Antigenics) and semi-synthetic saponin GPI-0100 (Advanced BioTherapies) were used as positive control adjuvants. Sera were analyzed by ELISA against synthetic globo H ceramide or GD3 and KLH. Results Consistent significant adjuvant activity was observed after s.c vaccination with the Coriolus extracts (especially PSK), a 95% ethanol extract of astragalus and yeast β-glucan, and (to a lesser extent) Maitake. Antibodies against KLH in all cases and against globo H in most cases were induced by these botanicals. Little or no adjuvant activity was demonstrated with H48 or Echinacea extracts or the astragalus water extract. Experiments with GD3-KLH as immunogen confirmed the adjuvant activity of the Coriolus, yeast β-glucan and Astragalus extracts. While extraction with ethanol concentrated the active ingredients in astragalus, it had no impact on coriolus where the 90% ethanol precipitate and solute were equally active. Conclusions Some, but not all, botanicals purported to be immune stimulants had adjuvant activity in our model. PSK and astragalus were surprisingly active and are being further fractionated to identify the most active adjuvant components. PMID:18640165
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Kassotis, Christopher D.; Tillitt, Donald E.; Davis, J. Wade; Hormann, Anette M.; Nagel, Susan C.
2014-01-01
The rapid rise in natural gas extraction using hydraulic fracturing increases the potential for contamination of surface and ground water from chemicals used throughout the process. Hundreds of products containing more than 750 chemicals and components are potentially used throughout the extraction process, including more than 100 known or suspected endocrine-disrupting chemicals. We hypothesized thataselected subset of chemicalsusedin natural gas drilling operationsandalso surface and ground water samples collected in a drilling-dense region of Garfield County, Colorado, would exhibit estrogen and androgen receptor activities. Water samples were collected, solid-phase extracted, and measured for estrogen and androgen receptor activities using reporter gene assays in human cell lines. Of the 39 unique water samples, 89%, 41%, 12%, and 46% exhibited estrogenic, antiestrogenic, androgenic, and antiandrogenic activities, respectively. Testing of a subset of natural gas drilling chemicals revealed novel antiestrogenic, novel antiandrogenic, and limited estrogenic activities. The Colorado River, the drainage basin for this region, exhibited moderate levels of estrogenic, antiestrogenic, and antiandrogenic activities, suggesting that higher localized activity at sites with known natural gas–related spills surrounding the river might be contributing to the multiple receptor activities observed in this water source. The majority of water samples collected from sites in a drilling-dense region of Colorado exhibited more estrogenic, antiestrogenic, or antiandrogenic activities than reference sites with limited nearby drilling operations. Our data suggest that natural gas drilling operationsmayresult in elevated endocrine-disrupting chemical activity in surface and ground water.
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Castillo, Sandra L; Heredia, Norma; Contreras, Juan F; García, Santos
2011-08-01
Campylobacter spp. is recognized as one of the most common cause of food-borne bacterial gastroenteritis in humans. Campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery-type illnesses with severe complications, such as Guillian-Barre syndrome. Epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been proposed to be critical steps in pathogenesis. Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. In this study, 28 edible or medicinal plants species were analyzed for their bactericidal effects on the growth of Campylobacter jejuni and C. coli. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus-indica, and Cynara scolymus were the most effective against these microorganisms at minimal bactericidal concentrations (MBCs) of 0.3, 0.5, 0.4, and 2.0 mg/mL, respectively. No effect on growth was detected with lower concentrations of extract (25%, 50%, or 75% of the MBC) added to the media. The effect of each extract (75% of the MBC) on adherence and cytotoxicity of C. jejuni and C. coli was evaluated in Vero cells. Adherence of Campylobacter to Vero cells was significantly affected by all the extracts. Cytotoxic activity of bacterial cultures was inhibited by A. farnesiana and A. ludoviciana. These plant extracts are potential candidates to be studied for controlling Campylobacter contamination in foods and the diseases associated with this microorganism. Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus-indica, and Cynara scolymus were the most effective against these microorganisms. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces which are critical steps in pathogenesis were decreased by these extracts. Our results point to these plants as potential candidates for the control of Campylobacter contamination in foods, the treatment of the diseases associated with this microorganism, and as feed supplements to reduce on-farm prevalence of Campylobacter. © 2011 Institute of Food Technologists®
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Yamashita, Yoshiko; Ichihara, Shu; Moritani, Suzuko; Yoon, Han-Seung; Yamaguchi, Masahiro
2016-06-01
Columnar cell lesions of the breast encompass columnar cell change/hyperplasia (CCC/CCH) and flat epithelial atypia (FEA). These have attracted researchers because emerging data suggest that FEA may represent the earliest histologically detectable non-obligate precursor of breast cancer. However, it is occasionally difficult to distinguish FEA from CCC/CCH because of similar histology. Although the nuclei of FEA are frequently described as relatively round compared with those of CCC/CCH, there are few morphometric studies to support this statement. The aim of this study was to provide objective data as to the nuclear shape in columnar cell lesions. As a shape descriptor, we adopted ellipticity that is defined by the formula 2b/2a, where a is the length of the long axis of the ellipse and b is the length of the short axis. Contrary to circularity, ellipticity reflects the overall configuration of an ellipse irrespective of surface irregularity. Our image analysis included generating whole slide images, extracting glandular cell nuclei, measuring nuclear ellipticity, and superimposing graded colors based on execution of results on the captured images. A total of 7917 nuclei extracted from 22 FEA images and 5010 nuclei extracted from 13 CCC/CCH images were analyzed. There was a significant difference in nuclear roundness between FEA and CCC/CCH with mean ellipticity values of 0.723 and 0.679, respectively (p < 0.001, Welch's t test). Furthermore, FEA with malignancy had significantly rounder nuclei than FEA without malignancy (p < 0.001). Our preliminary results suggest that nuclear ellipticity is a key parameter in reproducibly classifying columnar cell lesions of the breast.
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Brannelly, Laura A; Roberts, Alexandra A; Skerratt, Lee F; Berger, Lee
2018-05-16
Amphibians are experiencing a great loss in biodiversity globally and one of the major causes is the infectious disease chytridiomycosis. This disease is caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), which infects and disrupts frog epidermis; however, pathological changes have not been explicitly characterized. Apoptosis (programmed cell death) can be used by pathogens to damage host tissue, but can also be a host mechanism of disease resistance for pathogen removal. In this study, we quantify epidermal cell death of infected and uninfected animals using two different assays: terminal transferase-mediated dUTP nick end-labelling (TUNEL), and caspase 3/7. Using ventral, dorsal, and thigh skin tissue in the TUNEL assay, we observe cell death in the epidermal cells in situ of clinically infected animals and compare cell death with uninfected animals using fluorescent microscopy. In order to determine how apoptosis levels in the epidermis change over the course of infection we remove toe-tip samples fortnightly over an 8-week period, and use a caspase 3/7 assay with extracted proteins to quantify activity within the samples. We then correlate caspase 3/7 activity with infection load. The TUNEL assay is useful for localization of cell death in situ, but is expensive and time intensive per sample. The caspase 3/7 assay is efficient for large sample sizes and time course experiments. However, because frog toe tip biopsies are small there is limited extract available for sample standardization via protein quantification methods, such as the Bradford assay. Therefore, we suggest estimating skin surface area through photographic analysis of toe biopsies to avoid consuming extracts during sample standardization.
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Velmurugan, Palanivel; Iydroose, Mahudunan; Mohideen, Mohmed Hanifa Abdul Kader; Mohan, Thankiah Selva; Cho, Min; Oh, Byung-Taek
2014-08-01
This study highlights the ability of nitrate-reducing Bacillus subtilis EWP-46 cell-free extract used for preparation of silver nanoparticles (AgNPs) by reduction of silver ions into nano silver. The production of AgNPs was optimized with several parameters such as hydrogen ion concentration, temperature, silver ion (Ag(+) ion) and time. The maximum AgNPs production was achieved at pH 10.0, temperature 60 °C, 1.0 mM Ag(+) ion and 720 min. The UV-Vis spectrum showed surface plasmon resonance peak at 420 nm, energy-dispersive X-ray spectroscopy (SEM-EDX) spectra showed the presence of element silver in pure form. Atomic force microscopy (AFM) and transmission electron microscopy images illustrated the nanoparticle size, shape, and average particle size ranging from 10 to 20 nm. Fourier transform infrared spectroscopy provided the evidence for the presence of biomolecules responsible for the reduction of silver ion, and X-ray diffraction analysis confirmed that the obtained nanoparticles were in crystalline form. SDS-PAGE was performed to identify the proteins and its molecular mass in the purified nitrate reductase from the cell-free extract. In addition, the minimum inhibitory concentration and minimum bactericidal concentration of AgNPs were investigated against gram-negative (Pseudomonas fluorescens) and gram-positive (Staphylococcus aureus) bacteria.
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Enhanced fluorescence detection using liquid-liquid extraction in a microfluidic droplet system.
Chen, Yan-Yu; Chen, Zhao-Ming; Wang, Hsiang-Yu
2012-11-07
Reducing the fluorescence background in microfluidic assays is important in obtaining accurate outcomes and enhancing the quality of detections. This study demonstrates an integrated process including cell labelling, fluorescence background reduction, and biomolecule detection using liquid-liquid extraction in a microfluidic droplet system. The cellular lipids in Chlorella vulgaris and NIH/3T3 cells were labelled with a hydrophobic dye, Nile red, to investigate the performance of the proposed method. The fluorescence background of the lipid detection can be reduced by 85% and the removal efficiency increased with the volume of continuous phase surrounding a droplet. The removal rate of the fluorescence background increased as the surface area to volume ratio of a droplet increased. Before Nile red was removed from the droplet, the signal to noise ratio was as low as 1.30 and it was difficult to distinguish cells from the background. Removing Nile red increased the signal to noise ratio to 22 and 34 for Chlorella vulgaris and NIH/3T3, respectively, and these were 17 fold and 10 fold of the values before extraction. The proposed method successfully demonstrates the enhancement of fluorescence detection of cellular lipids and has great potential in improving other fluorescence-based detections in microfluidic systems.
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Sulaiman, Ghassan Mohammad; Mohammed, Wasnaa Hatif; Marzoog, Thorria Radam; Al-Amiery, Ahmed Abdul Amir; Kadhum, Abdul Amir H; Mohamad, Abu Bakar
2013-01-01
To synthesize silver nanopaticles from leaves extract of Eucalyptus chapmaniana (E. chapmaniana) and test the antimicrobial of the nanoparticles against different pathogenic bacteria, yeast and its toxicity against human acute promyelocytic leukemia (HL-60) cell line. Ten milliliter of leaves extract was mixed with 90 mL of 0.01 mmol/mL or 0.02 mmol/mL aqueous AgNO3 and exposed to sun light for 1 h. A change from yellowish to reddish brown color was observed. Characterization using UV-vis spectrophotometery and X-ray diffraction analysis were performed. Antimicrobial activity against six microorganisms was tested using well diffusion method and cytoxicity test using 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a yellow tetrazole was obtained on the human leukemia cell line (HL-60). UV-vis spectral analysis showed silver surface plasmon resonance band at 413 nm. X-ray diffraction showed that the particles were crystalline in nature with face centered cubic structure of the bulk silver with broad beaks at 38.50° and 44.76°. The synthesized silver nanoparticles efficiently inhibited various pathogenic organisms and reduced viability of the HL-60 cells in a dose-dependent manner. It has been demonstrated that the extract of E. chapmaniana leaves are capable of producing silver nanoparticles extracellularly and the Ag nanoparticles are quite stable in solution. Further studies are needed to fully characterize the toxicity and the mechanisms involved with the antimicrobial and anticancer activity of these particles.
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Staat, R H; Peyton, J C
1984-01-01
It is proposed that binding of oral streptococci to saliva-coated hydroxylapatite (SHA) surfaces is a multifactorial process involving both specific and nonspecific receptors. In this context, specific binding is described as a high-affinity, saturable interaction between the cell and binding surface. Conversely, nonspecific binding is considered to be a nonsaturable, generalized, low-affinity reaction. Experimental differentiation of specific binding from nonspecific binding was achieved with a competition assay which utilized a large excess of nonradiolabeled bacteria to compete with the 3H-labeled cells for attachment to receptors on 1.5 mg of SHA crystals. Competition assays of Streptococcus sanguis and Streptococcus mitis adhesion clearly demonstrated that the total binding isotherm was composed of a saturable specific binding reaction and a minor nonspecific binding component. This was further substantiated by analysis of nonlinear Scatchard plots of the total binding data. The competition data for Streptococcus mutans binding indicated that ca. 50% of the S. mutans binding appeared to be specific, although saturation of the SHA surfaces with bacterial cells could not be demonstrated. Experiments measuring desorption of radiolabeled cells from SHA crystals into buffer showed that ca. 50% of the bound S. mutans cells were removed after 4 h, whereas less than 5% of the S. sanguis cells were eluted from the SHA surfaces. The kinetics of attachment were studied by using an extract of Persea americana as a noncompetitive inhibitor of adherence. The total cell binding data for these experiments suggested a very rapid binding reaction followed by a slower rate of attachment. It was concluded from these three different experimental approaches that adherence of selected oral streptococci to SHA surfaces involves specific, high-affinity and nonspecific, low-affinity binding reactions. The concept is developed that in vitro streptococcal attachment to SHA can be described as a two-reaction process in which the low-affinity interaction of the cell with the SHA surface precedes the establishment of the stronger, specific bonds needed for the maintenance of streptococci in the oral cavity. PMID:6327530
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De, B P; Galinski, M S; Banerjee, A K
1990-03-01
A cell extract derived from human parainfluenza virus type 3-infected human lung carcinoma (HLC) cells synthesized mRNA in vitro. Under optimal conditions, the extract was able to support transcription of all virus-encoded genes as determined by hybridization analyses. The RNA products contained full-length poly(A)-containing mRNA species similar to those observed in acutely infected cells. Further purification of the viral nucleocapsids from the infected HLC cell extract resulted in total loss of the capacity of the extract to synthesize mRNA in vitro. However, the addition of cytoplasmic extracts from uninfected HLC cells to the nucleocapsid preparations restored transcription to levels observed in the infected cell lysates, indicating requirement of a host factor(s) in the human parainfluenza virus type 3 transcription process. In distinction to the abundant transcription observed in the cell extract from HLC cells, cell extract prepared from CV-1 cells failed to support transcription in vitro. High levels of RNase activity in the cell extract from CV-1 cells appears to be the principal reason for this difference.
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Salton, S R; Richter-Landsberg, C; Greene, L A; Shelanski, M L
1983-03-01
The PC12 clone of pheochromocytoma cells undergoes neuronal differentiation in the presence of nerve growth factor (NGF). Concomitant with this is a significant induction in the incorporation of radiolabeled fucose or glucosamine into a 230,000-dalton cell surface glycoprotein named the NGF-Inducible Large External, or NILE, glycoprotein (GP) (McGuire, J. C., L. A. Greene, and A. V. Furano (1978) Cell 15: 357-365). In the current studies NILE GP was purified from PC12 cells using wheat germ agglutinin-agarose affinity chromatography and SDS-polyacrylamide gel electrophoresis (PAGE). Polyclonal antisera were raised against purified NILE GP and were found to selectively immunoprecipitate a single 230,000-dalton protein from detergent extracts of PC12 cells metabolically labeled with either [3H]fucose, [3H]glucosamine, or [35S]methionine. These antisera stained the surfaces of PC12 cells by indirect immunofluorescence and were cytotoxic to PC12 cells in the presence of complement. Limited treatment of PC12 cells with either trypsin or pronase produced a fucosylated 90,000-dalton immunoreactive fragment of NILE GP which remained in the membrane. Using quantitative immunoelectrophoresis, the action of NGF on NILE GP was represent an increase in the amount of protein, rather than a selective increase in carbohydrate incorporation. Immunofluorescent staining of primary cell cultures and tissue whole mounts revealed that immunologically cross-reactive NILE GP appears to be expressed on the cell surfaces (somas and neurites) of most if not all peripheral and central neurons examined. Immunoprecipitation of radiolabeled cultures showed that the cross-reactive material had an apparent molecular weight by SDS-PAGE of 225,000 to 230,000 in the peripheral nervous system and 200,000 to 210,000 in the central nervous system. NILE-cross-reactive material was also found to a small extent on Schwann cell surfaces, but not at all on a variety of other cell types. These results suggest that immunoreactive NILE GP is distributed widely and selectively on neural cell surfaces.
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SERS and integrative imaging upon internalization of quantum dots into human oral epithelial cells.
Cepeda-Pérez, Elisa; López-Luke, Tzarara; Plascencia-Villa, Germán; Perez-Mayen, Leonardo; Ceja-Fdez, Andrea; Ponce, Arturo; Vivero-Escoto, Juan; de la Rosa, Elder
2016-07-01
CdTe quantum dots (QDs) are widely used in bio-applications due to their size and highly efficient optical properties. However internalization mechanisms thereof for the variety of freshly extracted, not cultivated human cells and their specific molecular interactions remains an open topic for discussion. In this study, we assess the internalization mechanism of CdTe quantum dots (3.3 nm) capped with thioglycolic acid using non cultivated oral epithelial cells obtained from healthy donors. Naked gold nanoparticles (40 nm) were successfully used as nanosensors for surface-enhanced Raman spectroscopy to efficiently identify characteristic Raman peaks, providing new evidence indicating that the first interactions of these QDs with epithelial cells occurred preferentially with aromatic rings and amine groups of amino acid residues and glycans from trans-membrane proteins and cytoskeleton. Using an integrative combination of advanced imaging techniques, including ultra-high resolution SEM, high resolution STEM coupled with EDX spectroscopy together with the results obtained by Raman spectroscopy, it was determined that thioglycolic acid capped CdTe QDs are efficiently internalized into freshly extracted oral epithelial cells only by facilitated diffusion, distributed into cytoplasm and even within the cell nucleus in three minutes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Ohyama, Kunio; Akaike, Takenori; Hirobe, Chieko; Yamakawa, Toshio
2003-01-01
A crude extract was prepared with ethanol from dried ripened Vitex agnus-castus fruits growing in Israel (Vitex extract). Cytotoxicity of the extract against human uterine cervical canal fibroblast (HCF), human embryo fibroblast (HE-21), ovarian cancer (MCF-7), cervical carcinoma (SKG-3a), breast carcinoma (SKOV-3), gastric signet ring carcinoma (KATO-III), colon carcinoma (COLO 201), and small cell lung carcinoma (Lu-134-A-H) cells was examined. After culture for 24 h (logarithmic growth phase) or 72 h (stationary growth phase), the cells were treated with various concentrations of Vitex extract. In both growth phases, higher growth activity of cells and more cytotoxic activity of Vitex extract were seen. The cytotoxic activity against stationary growth-phase cells was less than that against logarithmic growth-phase cells. DNA fragmentation of Vitex extract-treated cells was seen in SKOV-3, KATO-III, COLO 201, and Lu-134-A-H cells. The DNA fragmentation in Vitex extract-treated KATO-III cells was inhibited by the presence of the antioxidative reagent pyrrolidine dithiocarbamate or N-acetyl-L-cysteine (NAC). Western blotting analysis showed that in Vitex extract-treated KATO-III cells, the presence of NAC also inhibited the expression of heme oxygenase-1 and the active forms of caspases-3, -8 and -9. It is concluded that the cytotoxic activity of Vitex extract may be attributed to the effect on cell growth, that cell death occurs through apoptosis, and that this apoptotic cell death may be attributed to increased intracellular oxidation by Vitex extract treatment.
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Anticancer substances of mushroom origin.
Ivanova, T S; Krupodorova, T A; Barshteyn, V Y; Artamonova, A B; Shlyakhovenko, V A
2014-06-01
The present status of investigations about the anticancer activity which is inherent to medicinal mushrooms, as well as their biomedical potential and future prospects are discussed. Mushroom products and extracts possess promising immunomodulating and anticancer effects, so the main biologically active substances of mushrooms responsible for immunomodulation and direct cytoto-xicity toward cancer cell lines (including rarely mentioned groups of anticancer mushroom proteins), and the mechanisms of their antitumor action were analyzed. The existing to date clinical trials of mushroom substances are mentioned. Mushroom anticancer extracts, obtained by the different solvents, are outlined. Modern approaches of cancer treatment with implication of mushroom products, including DNA vaccinotherapy with mushroom immunomodulatory adjuvants, creation of prodrugs with mushroom lectins that can recognize glycoconjugates on the cancer cell surface, development of nanovectors etc. are discussed. The future prospects of mushroom anticancer substances application, including chemical modification of polysaccharides and terpenoids, gene engineering of proteins, and implementation of vaccines are reviewed.
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Wei, Yujie; Zhang, Xuejie; Xu, Li; Yi, Shaoqiong; Li, Yi; Fang, Xiaohong; Liu, Huiliang
2012-10-01
Cigarette smoking is a well-known risk factor for cardiovascular disease. Smoking can cause vascular endothelial dysfunction and consequently trigger haemostatic activation and thrombosis. However, the mechanism of how smoking promotes thrombosis is not fully understood. Thrombosis is associated with the imbalance of the coagulant system due to endothelial dysfunction. As a vital anticoagulation cofactor, thrombomodulin (TM) located on the endothelial cell surface is able to regulate intravascular coagulation by binding to thrombin, and the binding results in thrombosis inhibition. This work focused on the effects of cigarette smoke extract (CSE) on TM-thrombin binding by atomic force microscopy (AFM) based single-molecule force spectroscopy. The results from both in vitro and live-cell experiments indicated that CSE could notably reduce the binding probability of TM and thrombin. This study provided a new approach and new evidence for studying the mechanism of thrombosis triggered by cigarette smoking.
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Efficient Boundary Extraction of BSP Solids Based on Clipping Operations.
Wang, Charlie C L; Manocha, Dinesh
2013-01-01
We present an efficient algorithm to extract the manifold surface that approximates the boundary of a solid represented by a Binary Space Partition (BSP) tree. Our polygonization algorithm repeatedly performs clipping operations on volumetric cells that correspond to a spatial convex partition and computes the boundary by traversing the connected cells. We use point-based representations along with finite-precision arithmetic to improve the efficiency and generate the B-rep approximation of a BSP solid. The core of our polygonization method is a novel clipping algorithm that uses a set of logical operations to make it resistant to degeneracies resulting from limited precision of floating-point arithmetic. The overall BSP to B-rep conversion algorithm can accurately generate boundaries with sharp and small features, and is faster than prior methods. At the end of this paper, we use this algorithm for a few geometric processing applications including Boolean operations, model repair, and mesh reconstruction.
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Light sources and output couplers for a backlight with switchable emission angles
NASA Astrophysics Data System (ADS)
Fujieda, Ichiro; Imai, Keita; Takagi, Yoshihiko
2007-09-01
For switching viewing angles of a liquid crystal display, we proposed to place a liquid crystal device between an LED and a light-guide of a backlight. The first key component for this configuration is a light source with electronically-controlled emission angles. Here, we construct such a device by stacking an optical film and a polymer-network liquid crystal (PNLC) cell on top of a chip-type LED. The optical film contains opaque parallel plates that limit the LED output in a narrow angular range. The PNLC cell either transmits or scatters the light emerging from the optical film. Experiment using a 15μm-thick PNLC cell shows that the angular distribution becomes 2.3 times wider by turning off the PNLC cell. We place this light source at one end of a light-guide so that the angular distribution of the light propagating inside is controlled. The second key component is some types of micro-strucrures built on the light-guide to out-couple the propagating light. We first attached various optical films on a light-guide surface. Although the angular distribution of the extracted light was switched successfully, light was mostly emitted into an oblique direction, approximately 60° from the plane normal. Next, we used a half-cylinder in place of the optical films. The curved surface of the cylinder was attached to the light-guide with a small amount of matching oil, which constituted an optical window. We measured that the angular distribution of the extracted light decreased to 35° FWHM from 62° FWHM by turning on the PNLC cell.
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Michalak, Barbara; Filipek, Agnieszka; Chomicki, Piotr; Pyza, Małgorzata; Woźniak, Marta; Żyżyńska-Granica, Barbara; Piwowarski, Jakub P.; Kicel, Agnieszka; Olszewska, Monika A.; Kiss, Anna K.
2018-01-01
Aim of the study: Taking into account that overactivated leukocytes are an important factor in the development of many chronic diseases, we investigated the activity of phytochemically characterized (HPLC-DAD-MSn) extracts from forsythia leaves and flowers on the pro- and anti-inflammatory functions of leukocytes (effects on IL-1β, IL-8, TNF-α, and TGFβ release) and their adherence to endothelial cells. Using bio-guided fractionation, we isolated the active compounds and determined their biological activity, and we included the positive control quercetin. Methods: The effect on IL-1β, TNF-α, IL-8, and TGF-α production by leukocytes was measured by enzyme-linked immunosorbent assay (ELISA). The surface expression of adhesion molecules was analyzed with flow cytometry, and the neutrophil attachment to the endothelial cells was assessed fluorimetrically. The effects on p38MAPK, ERK1/2 and JNK phosphorylation were determined using western blots. Results: Leaf extracts had the effect of decreasing TNF-α production in neutrophils and monocyte/macrophage cells. The bio-guided fractionation led to the isolation of the following lignan aglycones: (+)-pinoresinol, (+)-epipinoresinol, (−)-matairesinol, (+)-phillygenin, and (−)-arctigenin. Only phillygenin was able to stimulate the anti-inflammatory function of macrophages by inducing TGF-β release and IL-10 receptor surface expression. Arctigenin, phillygenin, and a metabolite produced by the gut microbiota, enterolactone, decreased TNF-α and IL-1β production and neutrophil adhesion to endothelial cells, probably by attenuating the p38 and ERK kinase pathways. Conclusion: Forsythia x intermedia is a valuable source of active lignans, which may be potential candidates for treating inflammatory diseases that are associated with the excessive production of cytokines such as TNF-α and IL-1β. PMID:29740324
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Michalak, Barbara; Filipek, Agnieszka; Chomicki, Piotr; Pyza, Małgorzata; Woźniak, Marta; Żyżyńska-Granica, Barbara; Piwowarski, Jakub P; Kicel, Agnieszka; Olszewska, Monika A; Kiss, Anna K
2018-01-01
Aim of the study: Taking into account that overactivated leukocytes are an important factor in the development of many chronic diseases, we investigated the activity of phytochemically characterized (HPLC-DAD-MS n ) extracts from forsythia leaves and flowers on the pro- and anti-inflammatory functions of leukocytes (effects on IL-1β, IL-8, TNF-α, and TGFβ release) and their adherence to endothelial cells. Using bio-guided fractionation, we isolated the active compounds and determined their biological activity, and we included the positive control quercetin. Methods: The effect on IL-1β, TNF-α, IL-8, and TGF-α production by leukocytes was measured by enzyme-linked immunosorbent assay (ELISA). The surface expression of adhesion molecules was analyzed with flow cytometry, and the neutrophil attachment to the endothelial cells was assessed fluorimetrically. The effects on p38MAPK, ERK1/2 and JNK phosphorylation were determined using western blots. Results: Leaf extracts had the effect of decreasing TNF-α production in neutrophils and monocyte/macrophage cells. The bio-guided fractionation led to the isolation of the following lignan aglycones: (+)-pinoresinol, (+)-epipinoresinol, (-)-matairesinol, (+)-phillygenin, and (-)-arctigenin. Only phillygenin was able to stimulate the anti-inflammatory function of macrophages by inducing TGF-β release and IL-10 receptor surface expression. Arctigenin, phillygenin, and a metabolite produced by the gut microbiota, enterolactone, decreased TNF-α and IL-1β production and neutrophil adhesion to endothelial cells, probably by attenuating the p38 and ERK kinase pathways. Conclusion: Forsythia x intermedia is a valuable source of active lignans, which may be potential candidates for treating inflammatory diseases that are associated with the excessive production of cytokines such as TNF-α and IL-1β.
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NASA Astrophysics Data System (ADS)
Oh, Y. J.; Jo, W.; Yang, Y.; Park, S.
2007-04-01
The authors report growth media dependence of electrostatic force characteristics in Escherichia coli O157:H7 biofilm through local measurement by electrostatic force microscopy (EFM). The difference values of electrostatic interaction between the bacterial surface and the abiotic surface show an exponential decay behavior during biofilm development. In the EFM data, the biofilm in the low nutrient media shows a faster decay than the biofilm in the rich media. The surface potential in the bacterial cells was changed from 957to149mV. Local characterization of extracellular materials extracted from the bacteria reveals the progress of the biofilm formation and functional complexities.
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Zhamanbaeva, G T; Murzakhmetova, M K; Tuleukhanov, S T; Danilenko, M P
2014-12-01
We studied the effects of ethanol extract from Hippophae rhamnoides L. leaves on the growth and differentiation of human acute myeloid leukemia cells (KG-1a, HL60, and U937). The extract of Hippophae rhamnoides L. leaves inhibited cell growth depending on the cell strain and extract dose. In a high concentration (100 μg/ml), the extract also exhibited a cytotoxic effect on HL60 cells. Hippophae rhamnoides L. leaves extract did not affect cell differentiation and did not modify the differentiating effect of calcitriol, active vitamin D metabolite. Inhibition of cell proliferation was paralleled by paradoxical accumulation of phase S cells (synthetic phase) with a reciprocal decrease in the count of G1 cells (presynthetic phase). The extract in a concentration of 100 μg/ml induced the appearance of cells with a subdiploid DNA content (sub-G1 phase cells), which indicated induction of apoptosis. The antiproliferative effect of Hippophae rhamnoides L. extract on acute myeloid leukemia cells was at least partially determined by activation of the S phase checkpoint, which probably led to deceleration of the cell cycle and apoptosis induction.
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Allan, J T; Yan, Z; Kornacki, J L
2004-12-01
The effects of surface type (stainless steel, acetal resin, and fiberglass reinforced plastic wall paneling [FRP]), soil, and temperature on the survival of Listeria monocytogenes, Salmonella spp., and Yersinia enterocolitica, in the presence of condensate were evaluated. Surface coupons--half soiled with sterile porcine serum--were exposed to cell suspensions made from individual five-strain cocktails composed of organisms from the same genus (10(7) CFU/ml) in Butterfield's phosphate buffer and incubated for 2 h at 25 degrees C allowing attachment of cells to coupon surfaces. Coupons were rinsed to remove unattached cells, incubated at either 4 or 10 degrees C under condensate-forming conditions, and sampled at six time intervals over a 15-day period. For enumeration, cells were removed from the coupons by vigorous shaking in 100 ml of Butterfield's phosphate buffer with 3 g of glass beads and plated on tryptic soy agar with 0.6% yeast extract. Stainless steel did not support the survival of Listeria as well as acetal resin or FRP. Acetal resin and stainless steel were less supportive of Salmonella than FRP. All surfaces supported the survival of Yersinia over the 15-day trial equally. Temperature had little effect on survival of all organisms across all surfaces with one exception. However, Yersinia displayed growth on FRP at 10 degrees C. but death at 4 degrees C. Serum had a protective effect on L. monocytogenes on all surfaces, with populations sustained at significantly (P < or = 0.05) higher numbers over time than unsoiled coupons. Serum didnot effect survival of Salmonella or Yersinia on stainless steel, acetal resin, or FRP.
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Wendel, Mikael; Sommarin, Yngve; Heinegård, Dick
1998-01-01
A small cell-binding proteoglycan for which we propose the name osteoadherin was extracted from bovine bone with guanidine hydrochloride–containing EDTA. It was purified to homogeneity using a combination of ion-exchange chromatography, hydroxyapatite chromatography, and gel filtration. The Mr of the proteoglycan was 85,000 as determined by SDS-PAGE. The protein is rich in aspartic acid, glutamic acid, and leucine. Two internal octapeptides from the proteoglycan contained the sequences Glu-Ile-Asn-Leu-Ser-His-Asn-Lys and Arg-Asp-Leu-Tyr-Phe-Asn-Lys-Ile. These sequences are not previously described, and support the notion that osteoadherin belongs to the family of leucine-rich repeat proteins. A monospecific antiserum was raised in rabbits. An enzyme-linked immunosorbent assay was developed, and showed the osteoadherin content of bone extracts to be 0.4 mg/g of tissue wet weight, whereas none was found in extracts of various other bovine tissues. Metabolic labeling of primary bovine osteoblasts followed by immunoprecipitation showed the cells to synthesize and secrete the proteoglycan. Digesting the immunoprecipitated osteoadherin with N-glycosidase reduced its apparent size to 47 kD, thus showing the presence of several N-linked oligosaccharides. Digestion with keratanase indicated some of the oligosaccharides to be extended to keratan sulfate chains. In immunohistochemical studies of the bovine fetal rib growth plate, osteoadherin was exclusively identified in the primary bone spongiosa. Osteoadherin binds to hydroxyapatite. A potential function of this proteoglycan is to bind cells, since we showed it to be as efficient as fibronectin in promoting osteoblast attachment in vitro. The binding appears to be mediated by the integrin αvβ3, since this was the only integrin isolated by osteoadherin affinity chromatography of surface-iodinated osteoblast extracts. PMID:9566981
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Connections of intermediate filaments with the nuclear lamina and the cell periphery.
Katsuma, Y; Swierenga, S H; Marceau, N; French, S W
1987-01-01
We investigated the relationship between intermediate filaments (IFs) and other detergent- and nuclease-resistant filamentous structures of cultured liver epithelial cells (T51B cell line) using whole mount unembedded preparations which were sequentially extracted with Triton X-100 and nucleases. Immunogold labelling and stereoscopic observation facilitated the examination of each filamentous structure and their three-dimensional relationships to each other. After solubilizing phospholipid, nucleic acid and soluble cellular protein, the resulting cytoskeleton preparation consisted of a network of cytokeratin and vimentin IFs linked by 3 nm filaments. The IFs were anchored to and determined the position of the nuclear lamina filaments (NLF) network and the centrioles. The NLF was composed of the nuclear lamina filaments measuring 3-6 nm in diameter which radiated from and anchored to the skeleton of the nuclear pores. The IFs located in the nuclear region appeared to be interwoven with the NLF. At the cell surface, the IFs seemed to be attached to the putative actin filament network. They formed a focally interrupted plexus-like structure at the cell periphery. Fragments of vimentin filaments were found among the filamentous network located at the cell surface, and some filaments terminated blindly there.
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Possible importance of algal toxins in the Salton Sea, California
Reifel, K.M.; McCoy, M.P.; Rocke, T.E.; Tiffany, M.A.; Hurlbert, S.H.; Faulkner, D.J.
2002-01-01
In response to wildlife mortality including unexplained eared grebe (Podiceps nigricollis) die-off events in 1992 and 1994 and other mortality events including large fish kills, a survey was conducted for the presence of algal toxins in the Salton Sea. Goals of this survey were to determine if and when algal toxins are present in the Salton Sea and to describe the phytoplankton composition during those times. A total of 29 samples was collected for toxicity analysis from both nearshore and midlake sites visited biweekly from January to December 1999. Dinoflagellates and diatoms dominated most samples, but some were dominated by a prymnesiophyte (Pleurochrysis pseudoroscoffensis) or a raphidophyte (Chattonella marina). Several types of blooms were observed and sampled. The dinoflagellate Gyrodinium uncatenum formed an extensive, dense (up to 310 000 cells ml−1) and long-lasting bloom during the winter in 1999. A coccolithophorid, Pleurochrysis pseudoroscoffensis, occurred at high densities in surface films and nearshore areas during the spring and summer of 1999. These surface films also contained high densities of one or two other species (an unidentified scrippsielloid, Heterocapsa niei, Chattonella marina). Localized blooms were also observed in the Salton Sea. An unknown small dinoflagellate reached high densities (110 000 cells ml−1) inside Varner Harbor, and an unidentified species of Gymnodinium formed a dense (270 000 cells ml−1) band along part of the southern shoreline during the summer. Three species known to produce toxins in other systems were found. Protoceratium reticulatum (=Gonyaulax grindleyi) and Chattonella marina were found in several samples taken during summer months, and Prorocentrum minimum was found in low densities in several samples. Extracts of most samples, including those containing known toxic species, showed a low level (<10% mortality across all concentrations) of activity in the brine shrimp lethality assay and were not considered toxic. All sample extracts tested in the mouse bioassay showed no activity. One sample extract taken from the bloom of the small dinoflagellate was highly active (100% mortality across all concentrations) in the brine shrimp lethality assay, but the active material could not be isolated. While dense algal blooms are common at the Salton Sea, no evidence gathered in this study suggests that algal toxins are present within phytoplankton cells; however, toxins actively excreted by cells may have been missed. Blooms of phytoplankton likely contribute to wildlife mortality at the Salton Sea. Possible mechanisms including intoxication due to ingestion of feathers in grebes and waterlogging caused by changes in surface tension are discussed.
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Seaweed allelopathy to corals: are active compounds on, or in, seaweeds?
NASA Astrophysics Data System (ADS)
Longo, G. O.; Hay, M. E.
2017-03-01
Numerous seaweeds produce secondary metabolites that are allelopathic to corals. To date, most of the compounds identified in this interaction are lipid-soluble instead of water-soluble. Thus, understanding whether these compounds are stored internally where they would not contact corals, or occur on external surfaces where they could be transferred to corals, is critical to understanding seaweed-coral interactions and to informing realistic experiments on chemically mediated interactions. We conducted field experiments assessing the effects of lipid-soluble extracts from macroalgal surfaces alone versus total lipid-soluble extracts from both internal and external tissues on the coral Pocillopora verrucosa. Extracts of the red algae Amansia rhodantha and Asparagopsis taxiformis, the green alga Chlorodesmis fastigiata, and the brown alga Dictyota bartayresiana suppressed coral photochemical efficiency; in these bioactive species, the total lipid-soluble extracts were not more potent than surface-only extracts despite the concentration of total extracts being many times greater than surface-only extracts. This suggests that previous assays with total extracts may be ecologically meaningful, but also that future assays should be conducted with the simpler, less concentrated, and more ecologically relevant surface extracts. Allelopathic effects of As. taxiformis and C. fastigiata were significantly greater than the effect of D. bartayresiana, with effects of Am. rhodantha intermediate between these groups. Neither surface-only nor total lipid-soluble extracts of the seaweed Turbinaria ornata were allelopathic, and its lack of potency differed significantly from all other species. Our results suggest that lipid-soluble, allelopathic compounds are usually deployed on seaweed surfaces where they can be effective in surface-mediated interactions against other species.
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An optical sensing approach for the noninvasive transdermal monitoring of cortisol
NASA Astrophysics Data System (ADS)
Hwang, Yongsoon; Gupta, Niraj K.; Ojha, Yagya R.; Cameron, Brent D.
2016-03-01
Cortisol, a biomarker of stress, has recently been shown to have potential in evaluating the physiological state of individuals diagnosed with stress-related conditions including chronic fatigue syndrome. Noninvasive techniques to extract biomarkers from the body are a topic of considerable interest. One such technique to achieve this is known as reverse iontophoresis (RI) which is capable of extracting biomolecules through the skin. Unfortunately, however, the extracted levels are often considerably lower in concentration than those found in blood, thereby requiring a very sensitive analytical method with a low limit of detection. A promising sensing approach, which is well suited to handle such samples, is Surface Plasmon Resonance (SPR) spectroscopy. When coupled with aptamer modified surfaces, such sensors can achieve both selectivity and the required sensitivity. In this study, fabrication and characterization of a RIbased SPR biosensor for the measurement of cortisol has been developed. The optical mount and diffusion cell were both fabricated through the use of 3D printing techniques. The SPR sensor was configured to employ a prism couplerbased arrangement with a laser generation module and CCD line sensor. Cortisol-specific DNA aptamers were immobilized onto a gold surface to achieve the necessary selectivity. For demonstration purposes, cortisol was extracted by the RI system using a skin phantom flow system capable of generating time dependent concentration profiles. The captured sample was then transported using a micro-fluidic platform from the RI collection site to the SPR sensor for real-time monitoring. Analysis and system control was accomplished within a developed LabVIEW® program.
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VALKAMA, ELENA; SALMINEN, JUHA‐PEKKA; KORICHEVA, JULIA; PIHLAJA, KALEVI
2003-01-01
The morphology, ultrastructure, density and distribution of trichomes on leaves of Betula pendula, B. pubescens ssp. pubescens, B. pubescens ssp. czerepanovii and B. nana were examined by means of light, scanning and transmission electron microscopy. The composition of flavonoids in ethanolic leaf surface extracts was analysed by high pressure liquid chromatography. All taxa examined contained both glandular and non‐glandular trichomes (short and/or long hairs) but differed from each other in trichome ultrastructure, density and location on the leaf. Leaves of B. pubescens were more hairy than those of B. pendula, but the latter species had a higher density of glandular trichomes. Of the two subspecies of B. pubescens, leaves of ssp. pubescens had more short hairs on the leaf surface and four times the density of glandular trichomes of leaves of ssp. czerepanovii, whereas, in the latter subspecies, short hairs occurred largely on leaf veins, as in B. nana. The glandular trichomes were peltate glands, consisting of medullar and cortical cells, which differed structurally. Cortical cells possessed numerous small, poorly developed plastids and small vacuoles, whereas medullar cells had several large plastids with well‐developed thylakoid systems and fewer vacuoles. In B. pubescens subspecies, vacuoles of the glandular cells contained osmiophilic deposits, which were probably phenolic, whereas in B. pendula, vacuoles of glandular trichomes were characterized by the presence of numerous myelin‐like membranes. The composition of epicuticular flavonoids also differed among species. The two subspecies of B. pubescens and B. nana shared the same 12 compounds, but five of these occurred only in trace amounts in B. nana. Leaf surface extracts of B. pendula contained just six flavonoids, three of which occurred only in this species. In summary, the structure, density and distribution of leaf trichomes and the composition of epicuticular flavonoids represent good taxonomic markers for Finnish birch species. PMID:12714363
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The atlA operon of Streptococcus mutans: role in autolysin maturation and cell surface biogenesis.
Ahn, Sang-Joon; Burne, Robert A
2006-10-01
The Smu0630 protein (AtlA) was recently shown to be involved in cell separation, biofilm formation, and autolysis. Here, transcriptional studies revealed that atlA is part of a multigene operon under the control of at least three promoters. The morphology and biofilm-forming capacity of a nonpolar altA mutant could be restored to that of the wild-type strain by adding purified AtlA protein to the medium. A series of truncated derivatives of AtlA revealed that full activity required the C terminus and repeat regions. AtlA was cell associated and readily extractable from with sodium dodecyl sulfate. Of particular interest, the surface protein profile of AtlA-deficient strains was dramatically altered compared to the wild-type strain, as was the nature of the association of the multifunctional adhesin P1 with the cell wall. In addition, AtlA-deficient strains failed to develop competence as effectively as the parental strain. Mutation of thmA, which can be cotranscribed with atlA and encodes a putative pore-forming protein, resulted in a phenotype very similar to that of the AtlA-deficient strain. ThmA was also shown to be required for efficient processing of AtlA to its mature form, and treatment of the thmA mutant strain with full-length AtlA protein did not restore normal cell separation and biofilm formation. The effects of mutating other genes in the operon on cell division, biofilm formation, or AtlA biogenesis were not as profound. This study reveals that AtlA is a surface-associated protein that plays a critical role in the network connecting cell surface biogenesis, biofilm formation, genetic competence, and autolysis.
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Toluene diisocyanate emission to air and migration to a surface from a flexible polyurethane foam.
Vangronsveld, Erik; Berckmans, Steven; Spence, Mark
2013-06-01
Flexible polyurethane foam (FPF) is produced from the reaction of toluene diisocyanate (TDI) and polyols. Because of the potential for respiratory sensitization following exposure to TDI, concerns have been raised about potential consumer exposure to TDI from residual 'free TDI' in FPF products. Limited and conflicting results exist in the literature concerning the presence of unreacted TDI remaining in FPF as determined by various solvent extraction and analysis techniques. Because residual TDI results are most often intended for application in assessment of potential human exposure to TDI from FPF products, testing techniques that more accurately simulated human contact with foam were designed. To represent inhalation exposure to TDI from polyurethane foam, a test that measured the emission of TDI to air was conducted. For simulation of human dermal exposure to TDI from polyurethane foam, a migration test technique was designed. Emission of TDI to air was determined for a representative FPF using three different emission test cells. Two were commercially available cells that employ air flow over the surface of the foam [the Field and Laboratory Emission Cell (FLEC®) and the Micro-Chamber/Thermal Extraction™ cell]. The third emission test cell was of a custom design and features air flow through the foam sample rather than over the foam surface. Emitted TDI in the air of the test cells was trapped using glass fiber filters coated with 1-(2-methoxyphenyl)-piperazine (MP), a commonly used derivatizing agent for diisocyanates. The filters were subsequently desorbed and analyzed by liquid chromatography/mass spectrometry. Measurement of TDI migration from representative foam was accomplished by placing glass fiber filters coated with MP on the outer surfaces of a foam disk and then compressing the filters against the disk using a clamping apparatus for periods of 8 and 24 h. The sample filters were subsequently desorbed and analyzed in the same manner as for the emission tests. Although the foam tested had detectable levels of solvent-extractable TDI (56ng TDI g(-1) foam for the foam used in emissions tests; 240-2800ng TDI g(-1) foam for the foam used in migration tests), no TDI was detected in any of the emission or migration tests. Method detection limits (MDLs) for the emissions tests ranged from 0.03 to 0.5ng TDI g(-1) foam (0.002-0.04ng TDI cm(-2) of foam surface), whereas those for the migration tests were 0.73ng TDI g(-1) foam (0.16ng TDI cm(-2) of foam surface). Of the three emission test methods used, the FLEC® had the lowest relative MDLs (by a factor of 3-10) by virtue of its high chamber loading factor. In addition, the FLEC® cell offers well-established conformity with emission testing standard methods.
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Miladpour, B; Rasti, M; Owji, A A; Mostafavipour, Z; Khoshdel, Z; Noorafshan, A; Zal, F
2017-05-01
Type 1 diabetes is an autoimmune disease caused by the destruction of β-cells in the pancreas. Bone marrow mesenchymal stem cells are multipotent and easy accessible adult stem cells that may provide options in the treatment of type 1 diabetes. Injured pancreatic extract can promote the differentiation of rat bone marrow mesenchymal stem cells into β-cells. We aimed to observe the effect of quercetin in differentiation and insulin secretion in β-cells. Bone marrow mesenchymal stem cells were obtained from the tibiae of rats. Cell surface markers were analyzed by flow cytometry. The cells were treated with rat injured pancreatic extract and quercetin for 2 weeks. Insulin secretion was measured by ELISA. Insulin expression and some islet factors were evaluated by RT-PCR. PDX1, a marker for β-cell function and differentiation, was evaluated by both immunocytochemistry and Western blot. β-cell count was determined by stereology and cell count assay. ELISA showed significant differences in insulin secretion in the cells treated with RIPE + 20 μM quercetin (0.55 ± 0.01 µg/L) compared with the cells treated with RIPE alone (0.48 ± 0.01 µg/L) (P = 0.026). RT-PCR results confirmed insulin expression in both groups. PDX1 protein was detected in both groups by Western blot and immunocytochemistry. Stereology results showed a significant increase in β-cell number in the RIPE + quercetin-treated cells (47 ± 2.0) when compared with RIPE treatment alone (44 ± 2.5) (P = 0.015). Quercetin has a strengthening effect on the differentiation of rat bone marrow mesenchymal stem cells into β-cells and increases insulin secretion from the differentiated β-cells in vitro.
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Quantitative Magnetic Separation of Particles and Cells using Gradient Magnetic Ratcheting
Murray, Coleman; Pao, Edward; Tseng, Peter; Aftab, Shayan; Kulkarni, Rajan; Rettig, Matthew; Di Carlo, Dino
2016-01-01
Extraction of rare target cells from biosamples is enabling for life science research. Traditional rare cell separation techniques, such as magnetic activated cell sorting (MACS), are robust but perform coarse, qualitative separations based on surface antigen expression. We report a quantitative magnetic separation technology using high-force magnetic ratcheting over arrays of magnetically soft micro-pillars with gradient spacing, and use the system to separate and concentrate magnetic beads based on iron oxide content (IOC) and cells based on surface expression. The system consists of a microchip of permalloy micro-pillar arrays with increasing lateral pitch and a mechatronic device to generate a cycling magnetic-field. Particles with higher IOC separate and equilibrate along the miro-pillar array at larger pitches. We develop a semi-analytical model that predicts behavior for particles and cells. Using the system, LNCaP cells were separated based on the bound quantity of 1μm anti-EpCAM particles as a metric for expression. The ratcheting cytometry system was able to resolve a ±13 bound particle differential, successfully distinguishing LNCaP from PC3 populations based on EpCAM expression, correlating with flow cytometry analysis. As a proof of concept, EpCAM-labeled cells from patient blood were isolated with 74% purity, demonstrating potential towards a quantitative magnetic separation instrument. PMID:26890496
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Detection of viability of micro-algae cells by optofluidic hologram pattern.
Wang, Junsheng; Yu, Xiaomei; Wang, Yanjuan; Pan, Xinxiang; Li, Dongqing
2018-03-01
A rapid detection of micro-algae activity is critical for analysis of ship ballast water. A new method for detecting micro-algae activity based on lens-free optofluidic holographic imaging is presented in this paper. A compact lens-free optofluidic holographic imaging device was developed. This device is mainly composed of a light source, a small through-hole, a light propagation module, a microfluidic chip, and an image acquisition and processing module. The excited light from the light source passes through a small hole to reach the surface of the micro-algae cells in the microfluidic chip, and a holographic image is formed by the diffraction light of surface of micro-algae cells. The relation between the characteristics in the hologram pattern and the activity of micro-algae cells was investigated by using this device. The characteristics of the hologram pattern were extracted to represent the activity of micro-algae cells. To demonstrate the accuracy of the presented method and device, four species of micro-algae cells were employed as the test samples and the comparison experiments between the alive and dead cells of four species of micro-algae were conducted. The results show that the developed method and device can determine live/dead microalgae cells accurately.
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Danshen extract circumvents drug resistance and represses cell growth in human oral cancer cells.
Yang, Cheng-Yu; Hsieh, Cheng-Chih; Lin, Chih-Kung; Lin, Chun-Shu; Peng, Bo; Lin, Gu-Jiun; Sytwu, Huey-Kang; Chang, Wen-Liang; Chen, Yuan-Wu
2017-12-29
Danshen is a common traditional Chinese medicine used to treat neoplastic and chronic inflammatory diseases in China. However, the effects of Danshen on human oral cancer cells remain relatively unknown. This study investigated the antiproliferative effects of a Danshen extract on human oral cancer SAS, SCC25, OEC-M1, and KB drug-resistant cell lines and elucidated the possible underlying mechanism. We investigated the anticancer potential of the Danshen extract in human oral cancer cell lines and an in vivo oral cancer xenograft mouse model. The expression of apoptosis-related molecules was evaluated through Western blotting, and the concentration of in vivo apoptotic markers was measured using immunohistochemical staining. The antitumor effects of 5-fluorouracil and the Danshen extract were compared. Cell proliferation assays revealed that the Danshen extract strongly inhibited oral cancer cell proliferation. Cell morphology studies revealed that the Danshen extract inhibited the growth of SAS, SCC25, and OEC-M1 cells by inducing apoptosis. The Flow cytometric analysis indicated that the Danshen extract induced cell cycle G0/G1 arrest. Immunoblotting analysis for the expression of active caspase-3 and X-linked inhibitor of apoptosis protein indicated that Danshen extract-induced apoptosis in human oral cancer SAS cells was mediated through the caspase pathway. Moreover, the Danshen extract significantly inhibited growth in the SAS xenograft mouse model. Furthermore, the Danshen extract circumvented drug resistance in KB drug-resistant oral cancer cells. The study results suggest that the Danshen extract could be a potential anticancer agent in oral cancer treatment.
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Eradication of high viable loads of Listeria monocytogenes contaminating food-contact surfaces
de Candia, Silvia; Morea, Maria; Baruzzi, Federico
2015-01-01
This study demonstrates the efficacy of cold gaseous ozone treatments at low concentrations in the eradication of high Listeria monocytogenes viable cell loads from glass, polypropylene, stainless steel, and expanded polystyrene food-contact surfaces. Using a step by step approach, involving the selection of the most resistant strain-surface combinations, 11 Listeria sp. strains resulted inactivated by a continuous ozone flow at 1.07 mg m-3 after 24 or 48 h of cold incubation, depending on both strain and surface evaluated. Increasing the inoculum level to 9 log CFU coupon-1, the best inactivation rate was obtained after 48 h of treatment at 3.21 mg m-3 ozone concentration when cells were deposited onto stainless steel and expanded polystyrene coupons, resulted the most resistant food-contact surfaces in the previous assays. The addition of naturally contaminated meat extract to a high load of L. monocytogenes LMG 23775 cells, the most resistant strain out of the 11 assayed Listeria sp. strains, led to its complete inactivation after 4 days of treatment. To the best of our knowledge, this is the first report describing the survival of L. monocytogenes and the effect of ozone treatment under cold storage conditions on expanded polystyrene, a commonly used material in food packaging. The results of this study could be useful for reducing pathogen cross-contamination phenomena during cold food storage. PMID:26236306
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Investigation of Biological Adhesives and Polyurea Crosslinked Silica-Based Aerogels
NASA Astrophysics Data System (ADS)
Lyons, Laura; Cauble, Meagan; Cole, Judith; Sabri, Firouzeh
2009-11-01
One of the key steps towards developing new technology for nerve repair is to look at the interaction mechanism and strength of biological components with the material under investigation. The existing technology for peripheral nerve repair relies on suturing techniques for attaching and immobilization of the implant. It is also limited to connecting two nerve components only, through a cylindrical-shaped unit which we will refer to as 1-D. The focus of our work is to develop an aerogel-based printed circuit board (PCB) system for precise guidance of multiple (n-D) neuronal components, simultaneously. Here we report on the adhesion strength of sciatic nerve segments removed from cadaver Sprague Dawley rats and the surface of treated and untreated polyurea cross-linked silica-based aerogels. The adhesion strength of the nerve to the aerogel surface was studied under varying environmental conditions as well as surface coating types. The coatings tested were basement membrane extract (BME), Cell Tak, and the combination. Since the mechanism of adhesion to cells and other surfaces is different and non-competing for BME and Cell Tak it is expected that a stronger adhesion should be accomplished by combining these two adhesives. The effect of temperature, nerve elasticity, and ionic concentration on the strength of adhesion was investigated also and will be reported.
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Koganti, Praveen; Tulsawani, Rajkumar; Sharma, Purva; Sharma, Manish; Arora, Shivani; Misra, Kshipra
2018-01-01
Ganoderma lucidum is known to exert many health benefits including effects to improve oxygen utilization. Therefore, this study was designed to evaluate the role of a hydroalcoholic G. lucidum extract in providing tolerance to HT22 cells grown under hypoxic conditions. HT22 cells were exposed to 0.5% O2 in the presence or absence of the extract for 24 hours. At the end of the exposure period, we performed cell viability assays, cell cycle analysis, and biochemical and protein expression studies. The extract-treated cells revealed less cell death, minimized caspase 3 and reactive oxygen species levels, and relieved G0/G1 cell cycle arrest compared with hypoxic cells cultured without the extract. Further, extract-treated cells showed improved expression of Nrf2, heme oxygenase 1, and metallothionein and stabilized levels of hypoxia-inducible factor 1α. Moreover, lower levels of nuclear factor-κB and tumor necrosis factor a were evident in extract-treated cells. Overall, the G. lucidum extract reduced hypoxia-induced cell death and augmented transcription factors (HIF-1α and Nrf2), conferring tolerance to hypoxia.
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Zhang, Ranran; Liu, Xujie; Xiong, Zhiyuan; Huang, Qianli; Yang, Xing; Yan, Hao; Ma, Jing; Feng, Qingling; Shen, Zhijian
2018-03-08
Micro/nanostructured TiO 2 /ZnO coating has been shown to possess multiple functions, including antibacterial activity and bioactivity. Osteoblast-like SaOS-2 cells were employed for evaluating the in vitro osteogenic capacity of this coating and positive results were obtained. However, traditional principles of osseointegration focus only on the osteogenic differentiation alone. The effects of immunomodulation on the osteogenic activity have been largely ignored. In this study, the inflammatory responses of macrophages on the micro/nanostructured TiO 2 /ZnO coating were investigated. The extract media of macrophage cell line RAW264.7 cultured on the TiO 2 /ZnO coating were collected as indirect co-culture conditioned media. The osteogenic activity of SaOS-2 cells in the conditioned media was investigated. Adhesion, ALP activity and extracellular mineralization of cells grown in the conditioned media extracted from the micro/nanostructured TiO 2 /ZnO coating were found to be enhanced, compared to those grown in the conditioned media extracted from the macroporous TiO 2 coating. The immune microenvironment produced by the micro/nanostructured TiO 2 /ZnO coating showed excellent capacity to promote osteogenesis, indicating that this coating could be a promising candidate for implant surface modification in orthopaedic and dental applications. Furthermore, this work could help us understand the interplay between the host immune system and the osteoimmunomodulatory properties of the biomaterials, and optimize the design for coating biomaterials.
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Solar cells for lunar applications by vacuum evaporation of lunar regolith materials
NASA Technical Reports Server (NTRS)
Ignatiev, Alex
1991-01-01
The National Space Exploration Initiative, specifically the Lunar component, has major requirements for technology development of critical systems, one of which is electrical power. The availability of significant electrical power on the surface of the Moon is a principal driver defining the complexity of the lunar base. Proposals to generate power on the Moon include both nuclear and solar (photovoltaic) systems. A more efficient approach is to attempt utilization of the existing lunar resources to generate the power systems. Synergism may occur from the fact that there have already been lunar materials processing techniques proposed for the extraction of oxygen that would have, as by-products, materials that could be specifically used to generate solar cells. The lunar environment is a vacuum with pressures generally in the 1 x 10(exp -10) torr range. Such conditions provide an ideal environment for direct vacuum deposition of thin film solar cells using the waste silicon, iron, and TiO2 available from the lunar regolith processing meant to extract oxygen. It is proposed, therefore, to grow by vacuum deposition, thin film silicon solar cells from the improved regolith processing by-products.
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Evaluation of Skin Surface as an Alternative Source of Reference DNA Samples: A Pilot Study.
Albujja, Mohammed H; Bin Dukhyil, Abdul Aziz; Chaudhary, Abdul Rauf; Kassab, Ahmed Ch; Refaat, Ahmed M; Babu, Saranya Ramesh; Okla, Mohammad K; Kumar, Sachil
2018-01-01
An acceptable area for collecting DNA reference sample is a part of the forensic DNA analysis development. The aim of this study was to evaluate skin surface cells (SSC) as an alternate source of reference DNA sample. From each volunteer (n = 10), six samples from skin surface areas (forearm and fingertips) and two traditional samples (blood and buccal cells) were collected. Genomic DNA was extracted and quantified then genotyped using standard techniques. The highest DNA concentration of SSC samples was collected using the tape/forearm method of collection (2.1 ng/μL). Cotton swabs moistened with ethanol yielded higher quantities of DNA than swabs moistened with salicylic acid, and it gave the highest percentage of full STR profiles (97%). This study supports the use of SSC as a noninvasive sampling technique and as a extremely useful source of DNA reference samples among certain cultures where the use of buccal swabs can be considered socially unacceptable. © 2017 American Academy of Forensic Sciences.
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Cuprous Oxide as a Potential Low-Cost Hole-Transport Material for Stable Perovskite Solar Cells.
Nejand, Bahram Abdollahi; Ahmadi, Vahid; Gharibzadeh, Saba; Shahverdi, Hamid Reza
2016-02-08
Inorganic hole-transport materials are commercially desired to decrease the fabrication cost of perovskite solar cells. Here, Cu2O is introduced as a potential hole-transport material for stable, low-cost devices. Considering that Cu2O formation is highly sensitive to the underlying mixture of perovskite precursors and their solvents, we proposed and engineered a technique for reactive magnetron sputtering. The rotational angular deposition of Cu2O yields high surface coverage of the perovskite layer for high rate of charge extraction. Deposition of this Cu2O layer on the pinhole-free perovskite layer produces devices with power conversion efficiency values of up to 8.93%. The engineered Cu2O layers showed uniform, compact, and crack-free surfaces on the perovskite layer without affecting the perovskite structure, which is desired for deposition of the top metal contact and for surface shielding against moisture and mechanical damages. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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THE UPTAKE OF RADIOCOLLOIDS BY MACROPHAGES IN VITRO
Gosselin, Robert E.
1956-01-01
Macrophages isolated from the rabbit peritoneal cavity extract radioactive colloidal gold from solutions in vitro. This reaction (ultraphagocytosis) involves two phases: the reversible adsorption of gold on the cell surface and the subsequent irreversible removal of surface-bound colloid into the cell. The latter process (called ingestion) appears to proceed at a rate which is proportional at any moment to the amount of gold attached to the cell surface; the latter in turn can be related to the concentration in extracellular fluid by a simple adsorption isotherm. In terms of rate, therefore, ingestion is related to the extracellular gold concentration in the same way that many enzyme reactions are related to the substrate concentration. Although enzyme kinetics are useful in describing rates of ultraphagocytosis, there is no evidence that enzymes participate in either adsorption or ingestion or that metabolic energy is required of the macrophage. Exudative leucocytes of the heterophilic series show little or no interaction with these finely dispersed gold sols (mean particle diameter 6 to 9 millimicrons). 37°C. three parameters are sufficient to characterize the reaction between gold and a suspension of macrophages, namely an affinity constant (1/Ks), an adsorption maximum (L), and a rate constant of ingestion (k 3). Although numerical values differed markedly among cells of different exudates, all three parameters were estimated in three instances. In these suspensions between 2 and 20 per cent of the surface-bound gold was ingested each minute (37°C., pH 7.4). Under conditions of surface saturation, it was estimated that tens of thousands of gold particles were attached to the surface of an average macrophage; this amount of colloid, however, occupied less than 1 per cent of the geometric area of the cell surface. Although surface saturation imposed an upper limit on the rate of ingestion, no practical limit was noted in the capacity of macrophages to continue the reaction. Optical measurements imply that within the cell agglutination of colloidal gold began promptly after its ingestion. These data are compared with published kinetic studies on the phagocytosis of microscopic particulates and on the parasitism of bacteria by virus. PMID:13319653
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Penn, E J; Hobson, C; Rees, D A; Magee, A I
1987-07-01
Extracts of metabolically labeled cultured epithelial cells have been analyzed by immunoprecipitation followed by SDS-PAGE, using antisera to the major high molecular mass proteins and glycoproteins (greater than 100 kD) from desmosomes of bovine muzzle epidermis. For nonstratifying cells (Madin-Darby canine kidney [MDCK] and Madin-Darby bovine kidney), and A431 cells that have lost the ability to stratify through transformation, and a stratifying cell type (primary human keratinocytes) apparently similar polypeptides were immunoprecipitated with our antisera. These comprised three glycoproteins (DGI, DGII, and DGIII) and one major nonglycosylated protein (DPI). DPII, which has already been characterized by others in stratifying tissues, appeared to be absent or present in greatly reduced amounts in the nonstratifying cell types. The desmosome glycoproteins were further characterized in MDCK cells. Pulse-chase studies showed all three DGs were separate translation products. The two major glycoprotein families (DGI and DGII/III) were both found to be synthesized with co-translational addition of 2-4 high mannose cores later processed into complex type chains. However, they became endo-beta-N-acetylglucosaminidase H resistant at different times (DGII/III being slower). None of the DGs were found to have O-linked oligosaccharides unlike bovine muzzle DGI. Transport to the cell surface was rapid for all glycoproteins (60-120 min) as demonstrated by the rate at which they became sensitive to trypsin in intact cells. This also indicated that they were exposed at the outer cell surface. DGII/III, but not DGI, underwent a proteolytic processing step, losing 10 kD of carbohydrate-free peptide, during transport to the cell surface suggesting a possible regulatory mechanism in desmosome assembly.
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Wu, Li; Huang, Jie; Yu, Xiaoxue; Zhou, Xiaoqing; Gan, Chaoye; Li, Ming; Chen, Yong
2014-02-01
The nonionic detergent extraction at 4 °C and the cholesterol-depletion-induced lipid raft disruption are the two widely used experimental strategies for lipid raft research. However, the effects of raft disruption and/or cold treatment on the ultrastructural and mechanical properties of cells are still unclear. Here, we evaluated the effects of raft disruption and/or cold (4 °C) treatment on these properties of living human umbilical vein endothelial cells (HUVECs). At first, the cholesterol-depletion-induced raft disruption was visualized by confocal microscopy and atomic force microscopy (AFM) in combination with fluorescent quantum dots. Next, the cold-induced cell contraction and the formation of end-branched filopodia were observed by confocal microscopy and AFM. Then, the cell-surface ultrastructures were imaged by AFM, and the data showed that raft disruption and cold treatment induced opposite effects on cell-surface roughness (a significant decrease and a significant increase, respectively). Moreover, the cell-surface mechanical properties (stiffness and adhesion force) of raft-disrupted- and/or cold-treated HUVECs were measured by the force measurement function of AFM. We found that raft disruption and cold treatment induced parallel effects on cell stiffness (increase) or adhesion force (decrease) and that the combination of the two treatments caused dramatically strengthened effects. Finally, raft disruption was found to significantly impair cell migration as previously reported, whereas temporary cold treatment only caused a slight but nonsignificant decrease in cell migration performed at physiological temperature. Although the mechanisms for causing these results might be complicated and more in-depth studies will be needed, our data may provide important information for better understanding the effects of raft disruption or cold treatment on cells and the two strategies for lipid raft research.
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Ventura, Marco; Jankovic, Ivana; Walker, D. Carey; Pridmore, R. David; Zink, Ralf
2002-01-01
We have identified and sequenced the genes encoding the aggregation-promoting factor (APF) protein from six different strains of Lactobacillus johnsonii and Lactobacillus gasseri. Both species harbor two apf genes, apf1 and apf2, which are in the same orientation and encode proteins of 257 to 326 amino acids. Multiple alignments of the deduced amino acid sequences of these apf genes demonstrate a very strong sequence conservation of all of the genes with the exception of their central regions. Northern blot analysis showed that both genes are transcribed, reaching their maximum expression during the exponential phase. Primer extension analysis revealed that apf1 and apf2 harbor a putative promoter sequence that is conserved in all of the genes. Western blot analysis of the LiCl cell extracts showed that APF proteins are located on the cell surface. Intact cells of L. johnsonii revealed the typical cell wall architecture of S-layer-carrying gram-positive eubacteria, which could be selectively removed with LiCl treatment. In addition, the amino acid composition, physical properties, and genetic organization were found to be quite similar to those of S-layer proteins. These results suggest that APF is a novel surface protein of the Lactobacillus acidophilus B-homology group which might belong to an S-layer-like family. PMID:12450842
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Cookson, A L; Wray, A; Handley, P S; Jacob, A E
1996-02-15
By comparison of the cell surface proteins derived from the outer membrane and fibrils from 14 Prevotella intermedia and 19 Prevotella nigrescens strains using SDS and analysed by SDS-PAGE, it was possible to distinguish the two species. A polypeptide of approx. 21 kDa distinguished P. intermedia strains, whereas two polypeptides of approx. 18 and 22 kDa could be used to identify P. nigrescens strains. Four other human oral black pigmented bacterial species (Porphyromonas gingivalis, Prevotella denticola, Prevotella loescheii and Prevotella melaninogenica) did not have the 18-, 21- or 22-kDa polypeptides shown by P. intermedia or P. nigrescens. The cell-associated proteolytic activity of eight strains of P. intermedia, 14 strains of P. nigrescens and one strain of P. gingivalis (W50) was assessed using four chromogenic substrates. The hydrolysis of the substrate GPPNA (indicative of dipeptidyl peptidase IV-like activity) and SAAPPNA (elastase-like activity) by P. intermedia strains varied from 32 to 114 units and 0.5 to 12.6 units of activity respectively, where one unit was defined as the amount of protease enzyme catalysing the formation of 1 nmol of p-nitroaniline under experimental conditions. 37.5% (3 of 8) of P. intermedia strains hydrolysed SAAPPNA (chymotrypsin-like enzyme activity) with activities of between 7 and 12 units. The hydrolysis of GPPNA and SAAAPNA by P. nigrescens strains was 32-149 and 3-16 units, respectively. 57% (8 of 14) of P. nigrescens strains hydrolysed SAAPPPNA with activities ranging from 3 to 8 units. None of the P. intermedia or P. nigrescens strains examined were found to have trypsin-like enzyme activity (BAPNA hydrolysis). The GPPNA and SAAAPNA hydrolytic activity associated with the proteases from Porphyromonas gingivalis W50 was at least twice that of P. intermedia and P. nigrescens strains. The similar peptidase activities of P. intermedia and P. nigrescens against chromogenic substrates cannot be used to differentiate the species, but SDS-PAGE of cell surface protein extracts allowed unambiguous speciation between P. intermedia and P. nigrescens. This simple technique of cell surface protein analysis can be performed in most laboratories and offers a convenient way by which to differentiate the two species.
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Liu, Yu-Chi; Lim, Chris H. L.; Lwin, Nyein C.; Teo, Ericia P.; Yam, Gary H.; Tan, Donald T.; Mehta, Jodhbir S.
2017-01-01
With any refractive correction, including Small Incision Lenticule Extraction (SMILE), there may be a residual refractive error that requires a retreatment. Here, we investigated the tissue responses following various retreatment procedures in a rabbit model of SMILE. All rabbits underwent a -6.00D correction with SMILE. Two weeks later, they underwent -1.00D enhancement by: (i) VisuMax Circle, followed by excimer ablation (S+C); (ii) secondary SMILE anterior to the primary procedure (S+SE); or (iii) surface ablation (S+P), and were examined for 28 days. S+P induced corneal edema and haze, and more CD11b- (23±6 cells) and TUNEL-positive (36±4 cells) cells in the central stromal superficial layers early post-operatively (p<0.001 compared to other procedures). The corneas appeared normal on day 28 after S+P, but had a lower number of keratocytes near the laser ablated plane compared to other procedures. S+SE and S+C did not induce corneal haze and resulted similar level of fibronectin. However, S+C resulted in more inflammatory (10±2 cells; p = 0.001) and apoptotic cells (25±2 cells; p<0.001) compared to S+SE (7±1 inflammatory cells and 21±3 apoptotic cells) early post-operatively. In conclusion, each SMILE retreatment method resulted in unique tissue responses. S+SE offers advantages, such as minimal inflammation and cell death, as well as maintaining a ‘flap-less’ surgery, over other procedures. However, depending on the degree of enhancement, the lenticule may become too thin to be extracted and the procedure becomes more difficult to perform than S+C and S+P. S+P can maintain corneal integrity by avoiding flap creation and is technically more simple to perform than the others, but the surgery needs to be supplemented with mitomycin-C in order to reduce inflammation and modulate better wound healing. PMID:28708898
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Interaction of capsaicinoids with cell membrane models does not correlate with pungency of peppers
NASA Astrophysics Data System (ADS)
Geraldo, Vananélia P. N.; Ziglio, Analine C.; Gonçalves, Débora; Oliveira, Osvaldo N.
2017-04-01
Mixed monolayers were prepared using phospholipids in order to mimic cell membranes and fractions of capsaicinoids (extracted from Malagueta, Caps-M, and Bhut Jolokia, Caps-B, peppers). According to their surface-pressure isotherms and polarization-modulated infrared reflection absorption spectra (PM-IRRAS), weak molecular-level interactions were observed between Caps and phospholipids. Both Caps-M and Caps-B penetrated into the alkyl tail region of the monolayer, interacted with the phosphate group of the phospholipids and affected hydration of their Cdbnd O groups. Since the physiological activity of Caps is not governed solely by interaction with cell membranes, it should require participation of a neuronal membrane receptor, e.g. vanilloid receptor (TRPV1).
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An efficient method for extraction of astaxanthin from green alga Haematococcus pluvialis.
Sarada, R; Vidhyavathi, R; Usha, D; Ravishankar, G A
2006-10-04
Haematococcus pluvialis is one of the potent organisms for production of astaxanthin, a high value ketocarotenoid. Astaxanthin is accumulated in thick-walled cyst cells of Haematococcus. The thick cell wall is made up of sporopollenin-like material, algaenan, which hinders solvent extraction of astaxanthin. In the present study, an improved method for extraction of astaxanthin without homogenization of cells is reported. Extractability of astaxanthin from cyst cells was evaluated by treating cells with various solvents and pretreating the cells with organic and mineral acids at 70 degrees C followed by acetone extraction. Hydrochloric acid treatment facilitated 86-94% extractability of astaxanthin. Treatment time, temperature, and concentration of the acid were found to be critical factors for maximum extractability. The treatment did not affect the astaxanthin ester profile and the treated cells can be preserved until further use.
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Goda, Shuichiro; Koga, Tomoyuki; Yamashita, Kenichiro; Kuriura, Ryo; Ueda, Toshifumi
2018-04-08
In Archaea and Bacteria, surface layer (S-layer) proteins form the cell envelope and are involved in cell protection. In the present study, a putative S-layer protein was purified from the crude extract of Pyrococcus horikoshii using affinity chromatography. The S-layer gene was cloned and expressed in Escherichia coli. Isothermal titration calorimetry analyses showed that the S-layer protein bound N-acetylglucosamine and induced agglutination of the gram-positive bacterium Micrococcus lysodeikticus. The protein comprised a 21-mer structure, with a molecular mass of 1,340 kDa, as determined using small-angle X-ray scattering. This protein showed high thermal stability, with a midpoint of thermal denaturation of 79 °C in dynamic light scattering experiments. This is the first description of the carbohydrate-binding archaeal S-layer protein and its characteristics.
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Berkovich, Liron; Earon, Gideon; Ron, Ilan; Rimmon, Adam; Vexler, Akiva; Lev-Ari, Shahar
2013-08-19
Fewer than 6% patients with adenocarcinoma of the pancreas live up to five years after diagnosis. Chemotherapy is currently the standard treatment, however, these tumors often develop drug resistance over time. Agents for increasing the cytotoxic effects of chemotherapy or reducing the cancer cells' chemo-resistance to the drugs are required to improve treatment outcome. Nuclear factor kappa B (NF-kB), a pro-inflammatory transcription factor, reportedly plays a significant role in the resistance of pancreatic cancer cells to apoptosis-based chemotherapy. This study investigated the effect of aqueous Moringa Oleifera leaf extract on cultured human pancreatic cancer cells - Panc-1, p34, and COLO 357, and whether it can potentiates the effect of cisplatin chemotherapy on these cells. The effect of Moringa Oleifera leaf extract alone and in combination with cisplatin on the survival of cultured human pancreatic cancer cells was evaluated by XTT-based colorimetric assay. The distribution of Panc-1 cells in the cell cycle following treatment with Moringa leaf extract was evaluated by flow cytometry, and evaluations of protein levels were via immunoblotting. Data of cell survival following combined treatments were analyzed with Calcusyn software. Moringa Oleifera leaf extract inhibited the growth of all pancreatic cell lines tested. This effect was significant in all cells following exposure to ≥0.75 mg/ml of the extract. Exposure of Panc-1 cells to Moringa leaf extract induced an elevation in the sub-G1 cell population of the cell-cycle, and reduced the expression of p65, p-IkBα and IkBα proteins in crude cell extracts. Lastly, Moringa Oleifera leaf extract synergistically enhanced the cytotoxic effect of cisplatin on Panc-1 cells. Moringa Oleifera leaf extract inhibits the growth of pancreatic cancer cells, the cells NF-κB signaling pathway, and increases the efficacy of chemotherapy in human pancreatic cancer cells.
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Han, Jong-Min; Kim, Min-Jung; Baek, Seung-Hwa; An, Sojin; Jin, Yue-Yan; Chung, Hae-Gon; Baek, Nam-In; Choi, Myung-Sook; Lee, Kyung-Tae; Jeong, Tae-Sook
2009-02-25
Antiatherosclerotic effects of ethanolic extracts of Artemisia princeps Pampanini cv. Sajabal (ESJ) were investigated in low-density lipoprotein receptor deficient (LDLR(-/-)) mice. The Western diet-induced high levels of total cholesterol and triglyceride were similar in the ESJ and control groups. However, circulating oxidized LDL was significantly decreased in the ESJ group (p < 0.05). ESJ also markedly decreased aortic expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta), and reduced the aortic lesion formation and macrophage accumulation by 36.7% (p < 0.05) and 43% (p < 0.01) in the control group, respectively. Additionally, ESJ inhibited atherogenic properties with cytokine-induced surface expression of cell adhesion molecules, chemokines, and monocyte adhesion to the human umbilical vein endothelial cells (HUVECs), and simultaneously suppressed nuclear factor-kappaB (NF-kappaB) activation. These results suggest that ethanolic extracts of Artemisia princeps Pampanini cv. Sajabal contributes to the antiatherosclerotic and anti-inflammatory activities in LDLR(-/-) mice.
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Chen, Qingtai; Liu, Dong; Wu, Chongchong; Yao, Kaisheng; Li, Zhiheng; Shi, Nan; Wen, Fushan; Gates, Ian D
2018-05-03
An activity-tunable biocatalyst for Nannochloropsis sp. cell-walls degradation was prepared by co-immobilization of cellulase and lysozyme on the surface of amino-functionalized magnetic nanoparticles (MNPs) employing glutaraldehyde. The competition between cellulase and lysozyme during immobilization was caused by the limited active sites of the MNPs. The maximum recovery of activities (cellulase: 78.9% and lysozyme: 69.6%) were achieved due to synergistic effects during dual-enzyme co-immobilization. The thermal stability in terms of half-life of the co-immobilized enzymes was three times higher than that in free form and had higher catalytic efficiency for hydrolysis of cell walls. Moreover, the co-immobilized enzymes showed greater thermal stability and wider pH tolerance than free enzymes under harsh conditions. Furthermore, the co-immobilized enzymes retained up to 60% of the residual activity after being recycled 6 times. This study provides a feasible approach for the industrialization of enzyme during cell-walls disruption and lipids extraction from Nannochloropsis sp. Copyright © 2018. Published by Elsevier Ltd.
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Live cell refractometry based on non-SPR microparticle sensor.
Liu, Chang; Chen, David D Y; Yu, Lirong; Luo, Yong
2013-06-01
Unlike the nanoparticles with surface plasmon resonance, the optical response of polystyrene microparticles (PSMPs) is insensitive to the chemical components of the surrounding medium under the wavelength-dependent differential interference contrast microscopy. This fact is exploited for the measurement of the refractive index of cytoplasm in this study. PSMPs of 400 nm in diameter were loaded into the cell to contact cytoplasm seamlessly, and the refractive index information of cytoplasm could be extracted by differential interference contrast microscopy operated at 420 nm illumination wavelength through the contrast analysis of PSMPs images. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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C-phycocyanin extraction assisted by pulsed electric field from Artrosphira platensis.
Martínez, Juan Manuel; Luengo, Elisa; Saldaña, Guillermo; Álvarez, Ignacio; Raso, Javier
2017-09-01
This paper assesses the application of pulsed electric fields (PEF) to the fresh biomass of Artrhospira platensis in order to enhance the extraction of C-phycocyanin into aqueous media. Electroporation of A. platensis depended on both electric field strength and treatment duration. The minimum electric field intensity for detecting C-phycocyanin in the extraction medium was 15kV/cm after the application of a treatment time 150μs (50 pulses of 3μs). However higher electric field strength were required when shorter treatment times were applied. Response surface methodology was used in order to investigate the influence of electric field strength (15-25kV/cm), treatment time (60-150μs), and temperature of application of PEF (10-40°C) on C-phycocyanin extraction yield (PEY). The increment of the temperature PEF treatment reduced the electric field strength and the treatment time required to obtain a given PEY and, consequently decreased the total specific energy delivered by the treatment. For example, the increment of temperature from 10°C to 40°C permitted to reduce the electric field strength required to extract 100mg/g d w of C-phycocyanin from 25 to 18kV/cm, and the specific energy input from 106.7 to 67.5kJ/Kg. Results obtained in this investigation demonstrated PEF's potential for selectively extraction C-phycocyanin from fresh A. platensis biomass. The purity of the C-phycocyanin extract obtained from the electroporated cells was higher than that obtained using other techniques based on the cell complete destruction. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Ceschini, Livônios; Campos, Elida Geralda
2006-01-16
We investigated the effect of Cochlospermum regium (Mart & Schrank) Pilger aqueous root extract on Chinese hamster ovarian (CHO)-K1 cells. The extract significantly decreased proliferation of CHO-K1 cells (EC(50)=1.5mg/mL). Apoptosis induction was analysed by fluorescent microscopy. Cell cultures treated with Cochlospermum regium extract for 4h contained 13.6% apoptotic cells after 24h (investigated by fluorescent DNA-microscopy with acridine orange/ethidium bromide staining). Characteristic chromatin condensation and fragmentation, verified by 4',6-diamidino-2-phenylindole (DAPI) staining, was observed in the cells after treatment with Cochlospermum regium extract. The results confirm the toxicity of Cochlospermum regium root extract to immortal, non-tumorigenic mammalian cells in vitro.
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Garcia Campoy, Abraham Heriberto; Perez Gutierrez, Rosa Martha; Manriquez-Alvirde, Gabriela; Muñiz Ramirez, Alethia
2018-01-01
The aim was to explore the efficacy of extract of Eysenhardtia polystachya -loaded silver nanoparticles (EP/AgNPs) on pancreatic β cells, INS-1 cells, and zebrafish as a valuable model for the study of diabetes mellitus. EP/AgNPs were synthesized using methanol/water bark extract of E. polystachya and characterized using various physicochemical techniques. Immersion of adult zebrafish in 111 mM glucose solution resulted in a sustained hyperglycemic, hyperlipidemic state, and serum insulin levels decreased. The synthesized EP/AgNPs showed an absorption peak at 413 nm on ultraviolet-visible spectroscopy, revealing the surface plasmon resonance of the nanoparticles. Transmission electron microscopy indicated that most of the particles were spherical, with a diameter of 10-12 nm, a polydispersity index of 0.197, and a zeta potential of -32.25 mV, suggesting high stability of the nanoparticles. EP/AgNPs promote pancreatic β-cell survival, insulin secretion, enhanced hyperglycemia, and hyperlipidemia in glucose-induced diabetic zebrafish. EP/AgNPs also showed protection of the pancreatic β-cell line INS-1 against hydrogen peroxide-induced oxidative injury. The results indicate that EP/AgNPs have good antidiabetic activity and therefore could be used to prevent the development of diabetes.
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[Inhibition effects of black rice pericarp extracts on cell proliferation of PC-3 cells].
Jiang, Weiwei; Yu, Xudong; Ren, Guofeng
2013-05-01
To observe the inhibitive effects of black rice pericarp extracts on cell proliferation of human prostate cancer cell PC-3 and to explore its effecting mechanism. The black rice pericarp extract was used to treat the PC-3 cells. The inhibitory effect of black rice pericarp extract on cells proliferation of PC-3 was tested by MTT method. Cell apoptosis rates and cell cycle were measured by flow cytometric assay (FCM). Western blot was used to study the protein expression levels of p38, p-p38, JNK, p-JNK. A dose-dependent and time-dependent proliferation inhibition of black rice pericarp extract was demonstrated in PC-3. The most prominent experiment condition was inhibitory concentration with 300microg/ml and treated for 72 h. The experiment result of flow cytometry analysis demonstrates that the apoptosis rate of PC-3 cells increased along with the increasing of black rice pericarp extract concentration, and a G1-S cell cycle arrest was induced in a dose-dependent manner. After PC-3 cell was treated with black rice pericarp extract for 72 h, the expressions of p-p38, p-JNK protein increased. Black rice pericarp extract could inhibit proliferation, change the cell cycle distributions and induce apoptosis in human prostatic cancer cell PC-3. Its inhibitory effect may be through promoting activation of the JNK, p38 signaling pathway. These results suggest that black rice pericarp extract maybe has an inhibitory effect on prostatic cancer.
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A method of extracting impervious surface based on rule algorithm
NASA Astrophysics Data System (ADS)
Peng, Shuangyun; Hong, Liang; Xu, Quanli
2018-02-01
The impervious surface has become an important index to evaluate the urban environmental quality and measure the development level of urbanization. At present, the use of remote sensing technology to extract impervious surface has become the main way. In this paper, a method to extract impervious surface based on rule algorithm is proposed. The main ideas of the method is to use the rule-based algorithm to extract impermeable surface based on the characteristics and the difference which is between the impervious surface and the other three types of objects (water, soil and vegetation) in the seven original bands, NDWI and NDVI. The steps can be divided into three steps: 1) Firstly, the vegetation is extracted according to the principle that the vegetation is higher in the near-infrared band than the other bands; 2) Then, the water is extracted according to the characteristic of the water with the highest NDWI and the lowest NDVI; 3) Finally, the impermeable surface is extracted based on the fact that the impervious surface has a higher NDWI value and the lowest NDVI value than the soil.In order to test the accuracy of the rule algorithm, this paper uses the linear spectral mixed decomposition algorithm, the CART algorithm, the NDII index algorithm for extracting the impervious surface based on six remote sensing image of the Dianchi Lake Basin from 1999 to 2014. Then, the accuracy of the above three methods is compared with the accuracy of the rule algorithm by using the overall classification accuracy method. It is found that the extraction method based on the rule algorithm is obviously higher than the above three methods.
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Salehi, Soheil; Shandiz, Seyed Ataollah Sadat; Ghanbar, Farinaz; Darvish, Mohammad Raouf; Ardestani, Mehdi Shafiee; Mirzaie, Amir; Jafari, Mohsen
2016-01-01
A rapid phytosynthesis of silver nanoparticles (AgNPs) using an extract from the aerial parts of Artemisia marschalliana Sprengel was investigated in this study. The synthesized AgNPs using A. marschalliana extract was analyzed by UV–visible spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy and further characterized by transmission electron microscopy, scanning electron microscopy, zeta potential, and energy-dispersive spectroscopy. Characteristic absorption bands of AgNPs were found near 430 nm in the UV–vis spectrum. Energy-dispersive spectroscopy analysis of AgNPs in the energy range 2–4 keV confirmed the silver signal due to surface plasmon resonance. Scanning electron microscopy and transmission electron microscopy results revealed that the AgNPs were mostly spherical with an average size ranging from 5 nm to 50 nm. The zeta potential value of −31 mV confirmed the stability of the AgNPs. AgNPs produced using the aqueous A. marschalliana extract might serve as a potent in vitro antioxidant, as revealed by 2,2-diphenyl-1-picryl hydrazyl assay. The present study demonstrates the anticancer properties of phytosynthesized AgNPs against human gastric carcinoma AGS cells. AgNPs exerted a dose-dependent inhibitory effect on the viability of cells. Real-time polymerase chain reaction was used for the investigation of Bax and Bcl-2 gene expression in cancer and normal cell lines. Our findings show that the mRNA levels of pro-apoptotic Bax gene expression were significantly upregulated, while the expression of anti-apoptotic Bcl-2 was declined in cells treated with AgNPs compared to normal cells. In addition, flow cytometric analysis showed that the number of early and late apoptotic AGS cells was significantly enhanced following treatment with AgNPs as compared to untreated cells. In addition, the AgNPs showed strong antibacterial properties against tested pathogenic bacteria such as Staphylococcus aureus, Bacillus cereus, Acinetobacter baumannii, and Pseudomonas aeruginosa. Based on the obtained data, we suggest that phytosynthesized AgNPs are good alternatives in the treatment of diseases because of the presence of bioactive agents. PMID:27199558
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Thompson, N L; Hixson, D C; Callanan, H; Panzica, M; Flanagan, D; Faris, R A; Hong, W J; Hartel-Schenk, S; Doyle, D
1991-01-01
Dipeptidyl peptidase IV (DPPIV) is a serine exoproteinase expressed at high levels in epithelial cells of kidney, liver and small intestine. Recently Watanabe, Kohima & Fujimoto [(1987) Experientia 43, 400-401] and Gossrau et al. [(1990) Histochem. J. 22, 172-173] reported that Fischer 344 rats are deficient in this enzyme. We have examined DPPIV expression in Fischer 344 rats available from U.S. and German suppliers and find that livers of the U.S. Fischer rats, in contrast with their German counterparts, express active DPPIV (D+). Northern analysis of liver RNA showed comparable levels of 3.4 kb and 5.6 kb DPPIV transcripts in both D+ rats from the U.S. and German (D-) rats. Monoclonal antibody (MAb) 236.3 to DPPIV immunoprecipitated at 150 kDa enzymically active (105 kDa, denatured) protein from surface-labelled D+ hepatocytes and reacted with canalicular and sinusoidal membranes (as shown by immunofluorescence microscopy). MAb 236.3 failed to immunoprecipitate a labelled peptide from D- cell extract or to stain D- liver sections. Polyclonal antibody (PAb) specific for DPPIV immunoprecipitated an enzymically active peptide from D+ hepatocyte extracts and a smaller, inactive peptide from D- hepatocyte extracts. Peptide maps of DPPIV immunoprecipitated from D+ extracts with MAb 236.3 and PAb were identical, but differed from that of the D- hepatocyte component recognized by PAb. The molecular basis of the DPPIV deficiency in the D- rats thus appears to be the translation of an enzymically inactive protein missing the epitope recognized by MAb 236.3. We have exploited these D- rats as hosts for syngeneic transplantation of liver cells from D+ Fischer rats. DPPIV expression is stable in the transplanted cells and allows them to be readily distinguished from the surrounding D- tissue. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:1705112
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2013-01-01
Background Fewer than 6% patients with adenocarcinoma of the pancreas live up to five years after diagnosis. Chemotherapy is currently the standard treatment, however, these tumors often develop drug resistance over time. Agents for increasing the cytotoxic effects of chemotherapy or reducing the cancer cells’ chemo-resistance to the drugs are required to improve treatment outcome. Nuclear factor kappa B (NF-kB), a pro-inflammatory transcription factor, reportedly plays a significant role in the resistance of pancreatic cancer cells to apoptosis-based chemotherapy. This study investigated the effect of aqueous Moringa Oleifera leaf extract on cultured human pancreatic cancer cells - Panc-1, p34, and COLO 357, and whether it can potentiates the effect of cisplatin chemotherapy on these cells. Methods The effect of Moringa Oleifera leaf extract alone and in combination with cisplatin on the survival of cultured human pancreatic cancer cells was evaluated by XTT-based colorimetric assay. The distribution of Panc-1 cells in the cell cycle following treatment with Moringa leaf extract was evaluated by flow cytometry, and evaluations of protein levels were via immunoblotting. Data of cell survival following combined treatments were analyzed with Calcusyn software. Results Moringa Oleifera leaf extract inhibited the growth of all pancreatic cell lines tested. This effect was significant in all cells following exposure to ≥0.75 mg/ml of the extract. Exposure of Panc-1 cells to Moringa leaf extract induced an elevation in the sub-G1 cell population of the cell-cycle, and reduced the expression of p65, p-IkBα and IkBα proteins in crude cell extracts. Lastly, Moringa Oleifera leaf extract synergistically enhanced the cytotoxic effect of cisplatin on Panc-1 cells. Conclusion Moringa Oleifera leaf extract inhibits the growth of pancreatic cancer cells, the cells NF-κB signaling pathway, and increases the efficacy of chemotherapy in human pancreatic cancer cells. PMID:23957955
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Growth-inhibitory effects of the red alga Gelidium amansii on cultured cells.
Chen, Yue-Hwa; Tu, Ching-Jung; Wu, Hsiao-Ting
2004-02-01
The objective of this study was to investigate the effects of Gelidium amansii, an edible red agar cultivated off the northeast coast of Taiwan, on the growth of two lines of cancer cells, murine hepatoma (Hepa-1) and human leukemia (HL-60) cells, as well as a normal cell line, murine embryo fibroblast cells (NIH-3T3). The potential role of G. amansii on the induction of apoptosis was also examined. The results indicated that all extracts from G. amansii, including phosphate-buffered saline (PBS) and methanol extracts from dried algae as well as the dimethyl sulfoxide (DMSO) extract from freeze-dried G. amansii agar, inhibited the growth of Hepa-1 and NIH-3T3 cells, but not the growth of HL-60 cells. Annexin V-positive cells were observed in methanol and DMSO extract-treated, but not PBS extract-treated Hepa-1 and NIH-3T3 cells, suggesting that the lipid-soluble extracts of G. amansii induced apoptosis. In summary, extracts of G. amansii from various preparations exhibited antiproliferative effects on Hepa-1 and NIH-3T3 cells, and apoptosis may play a role in the methanol and DMSO extract-induced inhibitory effects. However, the antiproliferative effects of PBS extracts was not through apoptosis. Moreover, the growth-inhibitory effects of G. amansii were not specific to cancer cells.
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Trumpaitė-Vanagienė, Rita; Čebatariūnienė, Alina; Tunaitis, Virginijus; Pūrienė, Alina; Pivoriūnas, Augustas
2018-02-01
To compare cytotoxicity of extracts derived from commonly used luting cements: Hoffmann's Zinc Phosphate (ZPC), GC Fuji Plus Resin Modified Glass Ionomer (RMGIC) and 3M ESPE RelyX Unicem Resin Cement (RC) on primary human gingival fibroblasts (HGFs). HGFs were exposed to different concentrations of the ZPC, RMGIC and RC extracts. The cytotoxicity was assessed with the PrestoBlue Cell Viability Reagent and viable cells were counted by a haemocytometer using the trypan blue exclusion test. In order to determine the primary mechanism of the cell death induced by extracts from different luting cements, the real-time monitoring of caspase-3/-7 activity and membrane integrity of cells was employed. The extracts from the RMGIC and ZPC decreased the metabolic activity and numbers of viable cells. Unexpectedly, the extracts from the RC evoked only small effects on the metabolic activity of HGFs with a decreasing number of viable cells in a dose-and time-dependent manner. The live cell imaging revealed that the apoptosis was the primary mechanism of a cell death induced by the extracts derived from the RMGIC, whereas the extracts from the RC and ZPC induced a cell death through a necrotic and caspase-independent pathway. The apoptosis was the primary mechanism of the cell death induced by the extracts derived from the RMGIC, whereas the extracts from the RC and ZPC induced a cell death via a necrotic pathway. We suggest that metabolic assays commonly used to assess the cytotoxicity of luting cements should be validated by alternative methods. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Šikić Pogačar, Maja; Klančnik, Anja; Bucar, Franz; Langerholc, Tomaž; Smole Možina, Sonja
2016-06-01
In order to survive in food-processing environments and cause disease, Campylobacter jejuni requires specific survival mechanisms, such as biofilms, which contribute to its transmission through the food chain to the human host and present a critical form of resistance to a wide variety of antimicrobials. Phytochemical analysis of thyme ethanolic extract (TE), thyme post-hydrodistillation residue (TE-R), and olive leaf extract (OE) using high-performance liquid chromatography with photodiode array indicates that the major compounds in TE and TE-R are flavone glucuronides and rosmarinic acid derivatives, and in OE verbascoside, luteolin 7-O-glucoside and oleuroside. TE and TE-R reduced C. jejuni adhesion to abiotic surfaces by up to 30% at 0.2-12.5 µg mL(-1) , with TE-R showing a greater effect. OE from 3.125 to 200 µg mL(-1) reduced C. jejuni adhesion to polystyrene by 10-23%. On the other hand, C. jejuni adhesion to PSI cl1 cells was inhibited by almost 30% over a large concentration range of these extracts. Our findings suggest that TE, the agro-food waste material TE-R, and the by-product OE represent sources of bioactive phytochemicals that are effective at low concentrations and can be used as therapeutic agents to prevent bacterial adhesion. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
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Cytotoxicity of extracts of spices to cultured cells.
Unnikrishnan, M C; Kuttan, R
1988-01-01
The cytotoxicity of the extracts from eight different spices used in the Indian diet was determined using Dalton's lymphoma ascites tumor cells and human lymphocytes in vitro and Chinese Hamster Ovary cells and Vero cells in tissue culture. Alcoholic extracts of the spices were found to be more cytotoxic to these cells than their aqueous extracts. Alcoholic extracts of several spices inhibited cell growth at concentrations of 0.2-1 mg/ml in vitro and 0.12-0.3 mg/ml in tissue culture. Ginger, pippali (native to India; also called dried catkins), pepper, and garlic showed the highest activity followed by asafetida, mustard, and horse-gram (native to India). These extracts also inhibited the thymidine uptake into DNA.
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The Effect of Sericin from Various Extraction Methods on Cell Viability and Collagen Production
Aramwit, Pornanong; Kanokpanont, Sorada; Nakpheng, Titpawan; Srichana, Teerapol
2010-01-01
Silk sericin (SS) can accelerate cell proliferation and attachment; however, SS can be extracted by various methods, which result in SS exhibiting different physical and biological properties. We found that SS produced from various extraction methods has different molecular weights, zeta potential, particle size and amino acid content. The MTT assay indicated that SS from all extraction methods had no toxicity to mouse fibroblast cells at concentrations up to 40 μg/mL after 24 h incubation, but SS obtained from some extraction methods can be toxic at higher concentrations. Heat-degraded SS was the least toxic to cells and activated the highest collagen production, while urea-extracted SS showed the lowest cell viability and collagen production. SS from urea extraction was severely harmful to cells at concentrations higher than 100 μg/mL. SS from all extraction methods could still promote collagen production in a concentration-dependent manner, even at high concentrations that are toxic to cells. PMID:20559510
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Magnetic propulsion of microspheres at liquid-glass interfaces
NASA Astrophysics Data System (ADS)
Helgesen, Geir
2018-02-01
Bio-coated, magnetic microspheres have many applications in biotechnology and medical technology as a tool to separate and extract cells or molecules in a water solution by applying external strong magnetic field gradients. However, magnetic microspheres with or without attached cargo can also be separated in the liquid solution if they are exposed to alternating or rotating, relatively weak magnetic fields. Microspheres that have a higher density than the liquid will approach the bottom surface of the sample cell, and then a combination of viscous and surface frictional forces can propel the magnetic microspheres along the surface in a direction perpendicular to the axis of field rotation. Experiments demonstrating this type of magnetic propulsion are shown, and the forces active in the process are discussed. The motion of particles inside sample cells that were tilted relative to the horizontal direction was studied, and the variation of propulsion velocity as a function of tilt angle was used to find the values of different viscous and mechanical parameters of motion. Propulsion speeds of up to 5 μm/s were observed and were found to be caused by a partly rolling and partly slipping motion of rotating microspheres with a slipping coefficient near 0.6.
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Nanoscale imaging of photocurrent and efficiency in CdTe solar cells
Leite, Marina S.; National Inst. of Standards and Technology; Abashin, Maxim; ...
2014-10-15
The local collection characteristics of grain interiors and grain boundaries in thin film CdTe polycrystalline solar cells are investigated using scanning photocurrent microscopy. The carriers are locally generated by light injected through a small aperture (50-300 nm) of a near-field scanning optical microscope in an illumination mode. Possible influence of rough surface topography on light coupling is examined and eliminated by sculpting smooth wedges on the granular CdTe surface. By varying the wavelength of light, nanoscale spatial variations in external quantum efficiency are mapped. We find that the grain boundaries (GBs) are better current collectors than the grain interiors (GIs).more » The increased collection efficiency is caused by two distinct effects associated with the material composition of GBs. First, GBs are charged, and the corresponding built-in field facilitates the separation and the extraction of the photogenerated carriers. Second, the GB regions generate more photocurrent at long wavelength corresponding to the band edge, which can be caused by a smaller local band gap. As a result, resolving carrier collection with nanoscale resolution in solar cell materials is crucial for optimizing the polycrystalline device performance through appropriate thermal processing and passivation of defect and surfaces.« less
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Sulaiman, Ghassan Mohammad; Mohammed, Wasnaa Hatif; Marzoog, Thorria Radam; Al-Amiery, Ahmed Abdul Amir; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar
2013-01-01
Objective To synthesize silver nanopaticles from leaves extract of Eucalyptus chapmaniana (E. chapmaniana) and test the antimicrobial of the nanoparticles against different pathogenic bacteria, yeast and its toxicity against human acute promyelocytic leukemia (HL-60) cell line. Methods Ten milliliter of leaves extract was mixed with 90 mL of 0.01 mmol/mL or 0.02 mmol/mL aqueous AgNO3 and exposed to sun light for 1 h. A change from yellowish to reddish brown color was observed. Characterization using UV-vis spectrophotometery and X-ray diffraction analysis were performed. Antimicrobial activity against six microorganisms was tested using well diffusion method and cytoxicity test using 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a yellow tetrazole was obtained on the human leukemia cell line (HL-60). Results UV-vis spectral analysis showed silver surface plasmon resonance band at 413 nm. X-ray diffraction showed that the particles were crystalline in nature with face centered cubic structure of the bulk silver with broad beaks at 38.50° and 44.76°. The synthesized silver nanoparticles efficiently inhibited various pathogenic organisms and reduced viability of the HL-60 cells in a dose-dependent manner. Conclusions It has been demonstrated that the extract of E. chapmaniana leaves are capable of producing silver nanoparticles extracellularly and the Ag nanoparticles are quite stable in solution. Further studies are needed to fully characterize the toxicity and the mechanisms involved with the antimicrobial and anticancer activity of these particles. PMID:23570018
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Urea enhances cell lysis of Schizosaccharomyces pombe ura4 mutants.
Nishino, Kohei; Kushima, Misaki; Kaino, Tomohiro; Matsuo, Yasuhiro; Kawamukai, Makoto
2017-07-01
Cell lysis is induced in Schizosaccharomyces pombe ∆ura4 cells grown in YPD medium, which contains yeast extract, polypeptone, and glucose. To identify the medium components that induce cell lysis, we first tested various kinds of yeast extracts from different suppliers. Cell lysis of ∆ura4 cells on YE medium was observed when yeast extracts from OXOID, BD, Oriental, and Difco were used, but not when using yeast extract from Kyokuto. To determine which compounds induced cell lysis, we subjected yeast extract and polypeptone to GC-MS analysis. Ten kinds of compounds were detected in OXOID and BD yeast extracts, but not in Kyokuto yeast extract. Among them was urea, which was also present in polypeptone, and it clearly induced cell lysis. Deletion of the ure2 gene, which is responsible for utilizing urea, abolished the lytic effect of urea. The effect of urea was suppressed by deletion of pub1, and a similar phenotype was observed in the presence of polypeptone. Thus, urea is an inducer of cell lysis in S. pombe ∆ura4 cells.
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Qureshi, Mohammad A; Khatoon, Fehmeeda; Rizvi, Moshahid A; Zafaryab, Md
2015-01-01
High toxicity and multidrug resistance associated with various standard antimicrobial drugs have necessitated search for safer alternatives in plant-derived materials. In this study, we performed biological examination of chitosan-based hydrogel film loaded with ethyl acetate Salix alba leaves extract against 11 standard laboratory strains. FTIR showed regeneration of saccharide peak in CP1A at 1047 cm(-1) and increased in height of other peaks. DSC exothermic decomposition peaks at 112 °C, 175 °C and 251 °C reveal the effect of extract on hydrogel film. From FESEM images, three-dimensional cross-linking and extract easily seen in the globular form from the surface. MTT assay on HEK 293 cells showed that CP1A was non-toxic. Minimum inhibitory concentration ranges from 4000 μg/ml to 125 μg/ml. Enterococcus faecium, Candida glabrata and Candida tropicalis were the most resistant, while Salmonella typhi and Candida guilliermondii were the most susceptible micro-organisms.
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Jia, Xuejing; Zhang, Chao; Hu, Jie; He, Muxue; Bao, Jiaolin; Wang, Kai; Li, Peng; Chen, Meiwan; Wan, Jianbo; Su, Huanxing; Zhang, Qingwen; He, Chengwei
2015-11-23
Box-Behnken design (BBD), one of the most common response surface methodology (RSM) methods, was used to optimize the experimental conditions for ultrasound-assisted extraction of polysaccharides from Rhynchosia minima root (PRM). The antioxidant abilities and anticancer activity of purified polysaccharide fractions were also measured. The results showed that optimal extraction parameters were as follows: ultrasound exposure time, 21 min; ratio of water to material, 46 mL/g; ultrasound extraction temperature, 63 °C. Under these conditions, the maximum yield of PRM was 16.95%±0.07%. Furthermore, the main monosaccharides of purified fractions were Ara and Gal. PRM3 and PRM5 exhibited remarkable DPPH radical scavenging activities and reducing power in vitro. PRM3 showed strong inhibitory activities on the growth of MCF-7 cells in vitro. The above results indicate that polysaccharides from R. minima root have the potential to be developed as natural antioxidants and anticancer ingredients for the food and pharmaceutical industries.
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Myers, Jeremy N.; Rekhadevi, Perumalla V.; Ramesh, Aramandla
2011-01-01
Lysis and extraction of cells are essential sample processing steps for investigations pertaining to metabolism of xenobiotics in cell culture studies. Of particular importance to these procedures are maintaining high lysis efficiency and analyte integrity as they influence the qualitative and quantitative distribution of drug and toxicant metabolites in the intra- and extracellular milieus. In this study we have compared the efficiency of different procedures viz. homogenization, sonication, bead beating, and molecular grinding resin treatment for disruption of HT-29 colon cells exposed to benzo(a)pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH) compound and a suspected colon carcinogen. Also, we have evaluated the efficiency of various procedures for extracting BaP parent compound/metabolites from colon cells and culture media prior to High Performance Liquid Chromatography (HPLC) analyses. The extraction procedures include solid phase extraction, solid-supported liquid- liquid extraction, liquid-liquid extraction, and homogeneous liquid- liquid extraction. Our findings showed that bead-beating in combination with detergent treatment of cell pellet coupled with liquid-liquid extraction yielded greater concentrations of BaP metabolites compared to the other methods employed. Our method optimization strategy revealed that disruption of HT-29 colon cells by a combination of mechanical and chemical lysis followed by liquid-liquid extraction is efficient and robust enough for analyzing BaP metabolites from cell culture studies. PMID:21865728
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Nanoparticles of Selaginella doederleinii leaf extract inhibit human lung cancer cells A549
NASA Astrophysics Data System (ADS)
Syaefudin; Juniarti, A.; Rosiyana, L.; Setyani, A.; Khodijah, S.
2016-01-01
The aim of the present study is to evaluate cytotoxicity effect of nanoparticles of Selaginella doederleinii (S. doederleinii) leaves extract. S. doederleinii was extracted by maceration method using 70%(v/v) ethanol as solvent. Phytochemical content was analyzed qualitatively by using Harborne and Thin Layer Chromatography (TLC) methods. Nanoparticle extract was prepared by ionic gelation using chitosan as encapsulant agent. Anticancer activity was performed by using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The results showed that S. doederleinii contains of flavonoids. Nanoparticle of S. doederleinii leaves extract greatly inhibited A549 cells growth (cancer cells), with IC50 of 3% or 1020 μg/ml. These nanoparticles extract also inhibited the growth of Chang cells (normal cells), with IC50 of 4% or 1442 μg/ml. The effective concentration of nanoparticles extract which inhibits cancer cells without harming the normal cells is 0.5% or 167 μg/ml. Further studies are needed to obtain the concentration of nanoparticles extract which can selectively suppress cancer cells.
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Application of the Attagene FACTORIAL™ assay to ...
Bioassays can be used to evaluate the integrated effects of complex mixtures from both known and unidentified contaminants present in environmental samples. However, such bio-monitoring approaches have typically focused only on one or a few pathways (e.g. estrogen receptor, androgen receptor) despite the fact that the chemicals in a mixture may exhibit a range of biological activities. High-throughput screening approaches that can rapidly assess samples for a broad diversity of biological activities offer a means to provide a more comprehensive characterization of complex mixtures. The Attagene FactorialTM platform is a high-throughput, cell based assay utilized by US EPA’s ToxCast Program, which provides high-content assessment of over 90 different gene regulatory pathways and all 48 human nuclear receptors (NRs). This assay has previously been used in a preliminary screening of surface water extracts from sites across the Great Lakes. In the current study, surface waters samples from 38 sites were collected, extracted, and screened through the Factorial assay as part of a USGS nationwide stream assessment. All samples were evaluated in a six point, 3-fold dilution series and analyzed using the ToxCast Data Pipeline (TCPL) to generate dose-response curves and corresponding half-maximal activity concentration (AC50) estimates. A total of 27 assay endpoints responded to extracts from one or more sites, with up to 14 assays active for a single extract. The four
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In vitro antitumor actions of extracts from endemic plant Helichrysum zivojinii
2013-01-01
Background The aim of this research was to determine the intensity and mechanisms of the cytotoxic actions of five extracts isolated from the endemic plant species Helichrysum zivojinii Černjavski & Soška (family Asteraceae) against specific cancer cell lines. In order to evaluate the sensitivity of normal immunocompetent cells implicated in the antitumor immune response, the cytotoxicity of extracts was also tested against healthy peripheral blood mononuclear cells (PBMC). Methods The aerial parts of the plants were air-dried, powdered, and successively extracted with solvents of increasing polarity to obtain hexane, dichloromethane, ethyl-acetate, n-butanol and methanol extracts. The cytotoxic activities of the extracts against human cervix adenocarcinoma HeLa, human melanoma Fem-x, human myelogenous leukemia K562, human breast adenocarcinoma MDA-MB-361 cells and PBMC were evaluated by the MTT test. The mode of HeLa cell death was investigated by morphological analysis. Changes in the cell cycle of HeLa cells treated with the extracts were analyzed by flow cytometry. The apoptotic mechanisms induced by the tested extracts were determined using specific caspase inhibitors. Results The investigated Helichrysum zivojinii extracts exerted selective dose-dependent cytotoxic actions against selected cancer cell lines and healthy immunocompetent PBMC stimulated to proliferate, while the cytotoxic actions exerted on unstimulated PBMC were less pronounced. The tested extracts exhibited considerably stronger cytotoxic activities towards HeLa, Fem-x and K562 cells in comparison to resting and stimulated PBMC. It is worth noting that the cytotoxicity of the extracts was weaker against unstimulated PBMC in comparison to stimulated PBMC. Furthermore, each of the five extracts induced apoptosis in HeLa cells, through the activation of both intrinsic and extrinsic signaling pathways. Conclusion Extracts obtained from the endemic plant Helichrysum zivojinii may represent an important source of novel potential antitumor agents due to their pronounced and selective cytotoxic actions towards malignant cells. PMID:23414290
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In vitro antitumor actions of extracts from endemic plant Helichrysum zivojinii.
Matić, Ivana Z; Aljančić, Ivana; Žižak, Željko; Vajs, Vlatka; Jadranin, Milka; Milosavljević, Slobodan; Juranić, Zorica D
2013-02-18
The aim of this research was to determine the intensity and mechanisms of the cytotoxic actions of five extracts isolated from the endemic plant species Helichrysum zivojinii Černjavski & Soška (family Asteraceae) against specific cancer cell lines. In order to evaluate the sensitivity of normal immunocompetent cells implicated in the antitumor immune response, the cytotoxicity of extracts was also tested against healthy peripheral blood mononuclear cells (PBMC). The aerial parts of the plants were air-dried, powdered, and successively extracted with solvents of increasing polarity to obtain hexane, dichloromethane, ethyl-acetate, n-butanol and methanol extracts. The cytotoxic activities of the extracts against human cervix adenocarcinoma HeLa, human melanoma Fem-x, human myelogenous leukemia K562, human breast adenocarcinoma MDA-MB-361 cells and PBMC were evaluated by the MTT test. The mode of HeLa cell death was investigated by morphological analysis. Changes in the cell cycle of HeLa cells treated with the extracts were analyzed by flow cytometry. The apoptotic mechanisms induced by the tested extracts were determined using specific caspase inhibitors. The investigated Helichrysum zivojinii extracts exerted selective dose-dependent cytotoxic actions against selected cancer cell lines and healthy immunocompetent PBMC stimulated to proliferate, while the cytotoxic actions exerted on unstimulated PBMC were less pronounced. The tested extracts exhibited considerably stronger cytotoxic activities towards HeLa, Fem-x and K562 cells in comparison to resting and stimulated PBMC. It is worth noting that the cytotoxicity of the extracts was weaker against unstimulated PBMC in comparison to stimulated PBMC. Furthermore, each of the five extracts induced apoptosis in HeLa cells, through the activation of both intrinsic and extrinsic signaling pathways. Extracts obtained from the endemic plant Helichrysum zivojinii may represent an important source of novel potential antitumor agents due to their pronounced and selective cytotoxic actions towards malignant cells.
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Zhang, Dandan; Wu, Mengting; Guo, Yuxing; Xun, Mingyue; Wang, Wenwen; Wu, Zhen; Pan, Daodong
2017-09-01
Surface-layer proteins (SLP) have been found in the outermost layer of the cell wall in many types of lactobacillus are considered to be an important factor with respect to intestinal immunity. The present study compared the effects of SLP extracted by different concentrations of LiCl and carbamide, and subsequently identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, circular dichroism and differential scanning calorimetry. Furthermore, RAW 264.7 cells were used to evaluate the immunomodulatory effects of SLP. SLP were derived from Lactobacillus acidophilus CICC6074 with a molecular weight of 46 kDa, and consisted of 16.9% α-helix, 42.3% β-sheet, 20.8% β-turns and 22.5% random coils. SLP promoted NO secretion and higher quantities of NO were produced as the SLP concentrations increased. SLP concentrations over 50 µg mL -1 significantly decreased the amount of tumor necrosis factor-α secreted by RAW264.7 cells. SLP can trigger immunomodulatory effects in RAW 264.7 cells. This provides crucial information that will enable the further use of L. acidophilus in food, medicine and other products. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
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Chang, Cunjie; Zhao, Wei; Xie, Bingxian; Deng, Yongming; Han, Tao; Cui, Yangyan; Dai, Yundong; Zhang, Zhen; Gao, Jimin; Guo, Hongqian; Yan, Jun
2014-05-01
Pao extract, derived from bark of Amazonian tree Pao Pereira, is commonly used in South American medicine. A recent study showed that Pao extract repressed androgen-dependent LNCaP prostate cancer cell growth. We hypothesize that Pao extract asserts its anticancer effects on metastatic castration-resistant prostate cancer (CRPC) cells. Pao extract suppressed CRPC PC3 cell growth in a dose- and time-dependent manner, through induction of apoptosis and cell cycle arrest. Pao extract treatment induced cell cycle inhibitors, p21 and p27, and repressed PCNA, Cyclin A and Cyclin D1. Furthermore, Pao extract also induced the upregulation of pro-apoptotic Bax, reduction of anti-apoptotic Bcl-2, Bcl-xL, and XIAP expression, which were associated with the cleavage of PARP protein. Moreover, Pao extract treatment blocked PC3 cell migration and invasion. Mechanistically, Pao extract suppressed phosphorylation levels of AKT and NFκB/p65, NFκB DNA binding activity, and luciferase reporter activity. Pao inhibited TNFα-induced relocation of NFκB/p65 to the nucleus, NFκB/p65 transcription activity, and MMP9 activity as shown by zymography. Consistently, NFκB/p65 downstream targets involved in proliferation (Cyclin D1), survival (Bcl-2, Bcl-xL, and XIAP), and metastasis (VEGFa, MMP9, and GROα/CXCL1) were also downregulated by Pao extract. Finally, forced expression of NFκB/p65 reversed the growth inhibitory effect of Pao extract. Overall, Pao extract induced cell growth arrest, apoptosis, partially through inhibiting NFκB activation in prostate cancer cells. These data suggest that Pao extract may be beneficial for protection against CRPC. © The Author(s) 2013.
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Kwon, Taek Kwan; Kim, Jin-Chul
2014-10-01
The aims of this work are to enhance the in vitro skin permeation of Houttuynia cordata (water-soluble extract of H. cordata; HCWSE) and to boost the efficacy of HCWSE against atopic dermatitis (AD) - like skin lesion in hairless mice using lipid nano-carriers (liposome and cubosome). HCWSE was obtained by a hot water extraction. Monoolein cubosomal suspension containing HCWSE and egg phosphatidylcholine liposomal suspension containing the same was prepared by a sonication and a film hydration method, respectively. The lipid nano-carriers, especially cubosome, enhanced the in vitro skin permeation of HCWSE. The inhibitory effects of HCWSE-containing lipid carrier suspensions on the development of 1-chloro-2,4-dinitrobenzene (DNCB)-induced AD-like skin lesion in hairless mice were investigated by observing appearance of skin surface, serum immunoglobulin E (IgE) level and cytokine expression. HCWSE-containing preparations suppressed IgE production and interleukin 4 expression, whereas they promoted interferon gamma expression. The order of lymphocyte (B-cell, Th1 cell and Th2 cell) modulating effect was HCWSE-containing cubosomal suspension > HCWSE-containing liposomal suspension > HCWSE solution in phosphate buffered saline, indicating that the cubosomal suspension, among the preparations, was the most efficacious in inhibiting the development of DNCB-induced AD-like skin lesion. It is believed that the cubosomal suspension containing HCWSE would be an efficacious preparation for the treatment of AD.
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Yu, Fa-Rong; Yang, Bo; Li, Zuo-Ping; Lian, Xiu-Zhen; Xie, Ming-Ren; Li, Deng-Lou; Zhang, Shi-Shuang
2017-06-08
To investigate the effects of maca extract on the ultrastructures of mitochondria in the spinal nerve cell and exercise endurance. The Wistar rats were randomly divided into 5 groups, including the control group (no swimming), the swimming group (free swimming), and 3 treatment groups treated with the maca extract at the doses of 4.0, 5.3 and 8.0 g/kg body weight. The animals in swimming and treatment groups were then for free swimming in the circulating water flow daily for 15 days. On the 16 th day after swimming endurance, the spinal and muscular tissues were collected from all groups. The mitochondrial ultrastructures of the neurons of the spinal cells were observed with the projection electron microscope, and the levels of the glycogen, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and Ca 2+ in muscle tissues were determined by the RIA method. When rats were treated with maca extract (at 4.0, 5.3, 8.0 g/kg body weight), the total swimming time and the swimming duration before sinking were increased by 19.83%, 60.28%, 77.55%, and 55.34%, 73.91%, 94.47%, respectively, compared with the simple swimming group( P <0.01), while the sinking times were decreased by 34.35%, 51.18% and 57.96%, compared with those of the swimming group. Also, the levels of SOD, GSH-Px, and muscle glycogen in three treatment groups were enhanced by 5.12%, 22.74%, 52.53%, 44.22%, 77.79%, 98.45%( P <0.01), and 35.08%, 47.83%,81.88% ( P <0.01)respectively over the swimming rats without treatment, but the MDA content and the Ca 2+ levels were reduced by 20.10%, 31.49% 38.72%, and 6.42%, 17.58%, 26.35%,compared with the simple swimming group( P <0.01). In addition, compared to the swimming group, the mitochondrial densities of volume (VD), surface (SD) and numbers (ND) of spinal nerve cells in rats treated with maca extract (4.0, 5.3, 8.0 g/kg body weight) were reduced by 7.79%, 18.18%, 31.17%, 16.95%, 27.34%, 43.31% and 13.51%, 23.19%, 43.15%, respectively. Our results demonstrated the protective effects of maca extract on the mitochondria of spinal cell and suggested that maca extract could improve the muscle antioxidant activity by increasing the levels of SOD, GSH-Px, and muscle glycogen.
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Ultrasound Assisted Extraction of Phenolic Compounds from Peaches and Pumpkins
Altemimi, Ammar; Watson, Dennis G.; Choudhary, Ruplal; Dasari, Mallika R.; Lightfoot, David A.
2016-01-01
The ultrasound-assisted extraction (UAE) method was used to optimize the extraction of phenolic compounds from pumpkins and peaches. The response surface methodology (RSM) was used to study the effects of three independent variables each with three treatments. They included extraction temperatures (30, 40 and 50°C), ultrasonic power levels (30, 50 and 70%) and extraction times (10, 20 and 30 min). The optimal conditions for extractions of total phenolics from pumpkins were inferred to be a temperature of 41.45°C, a power of 44.60% and a time of 25.67 min. However, an extraction temperature of 40.99°C, power of 56.01% and time of 25.71 min was optimal for recovery of free radical scavenging activity (measured by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) reduction). The optimal conditions for peach extracts were an extraction temperature of 41.53°C, power of 43.99% and time of 27.86 min for total phenolics. However, an extraction temperature of 41.60°C, power of 44.88% and time of 27.49 min was optimal for free radical scavenging activity (judged by from DPPH reduction). Further, the UAE processes were significantly better than solvent extractions without ultrasound. By electron microscopy it was concluded that ultrasonic processing caused damage in cells for all treated samples (pumpkin, peach). However, the FTIR spectra did not show any significant changes in chemical structures caused by either ultrasonic processing or solvent extraction. PMID:26885655
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NASA Astrophysics Data System (ADS)
Yuan, Ye
TiO2 nanomaterials can carry a multitude of therapeutic and diagnostic agents and the semiconductor properties of TiO2 allow for the production of cytotoxic reactive oxygen species following photoactivation. However, the delivery of these nanomaterials to specific cancer cells and specific subcellular organelles within these cells can have a substantial impact on the efficacy and safety of TiO2 nanoparticle therapeutics. Targeting cell surface receptors that are overexpressed by cancer cells is one strategy to improve the specificity of nanoparticle delivery. Therefore we decided to target the Epidermal Growth Factor Receptor (EGFR) because ligand- binding induces rapid receptor endocytosis and ligand-bound EGFR can translocate to the nucleus of cancer cells. To create NPs that can bind EGFR, we identified a peptide derived from the B-loop of Epidermal Growth Factor (EGF) that has been shown to bind and activate EGFR and conjugated it to the surface of Fe3O4 core-TiO2 shell NPs to produce B-loop NCs. We then devised a pulldown assay to show that B-loop NCs, but not bare NPs or NCs carrying a scrambled B-loop peptide, can bind and extract EGFR from HeLa cell protein extracts. Interestingly, B-loop NCs can also pulldown importin-beta, a protein that can transport EGFR to the nucleus. Furthermore, we used flow cytometry and fluorescently labeled NPs to show that B-loop peptides can significantly improve the internalization of NPs by EGFR-expressing HeLa cells. We determined that B-loop NCs can bind EGFR on the membrane of HeLa cells and that these NCs can be transported to the nucleus, by using a combination of confocal microscopy and X-ray Fluorescence Microscopy (XFM) to indirectly and directly track the subcellular distribution of NCs. Finally, we demonstrate how the Bionanoprobe, a novel high-resolution XFM apparatus that can scan whole-mounted, frozen-hydrated cells at multiple angles can be used to verify the subcellular distribution of B-loop NCs.
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Abdullah, Al-Shwyeh Hussah; Mohammed, Abdulkarim Sabo; Abdullah, Rasedee; Mirghani, Mohamed Elwathig Saeed; Al-Qubaisi, Mothanna
2014-06-25
Waterlily Mango (Mangifera indica L.) is thought to be antioxidant-rich, conferred by its functional phytochemicals. The potential anticancer effects of the ethanolic kernel extract on breast cancer cells (MDA-MB-231 and MCF-7) using MTT, anti-proliferation, neutral red (NR) uptake and lactate dehydrogenase (LDH) release assays were evaluated. Cytological studies on the breast cancer cells were also conducted, and phytochemical analyses of the extract were carried out to determine the likely bioactive compounds responsible for such effects. Results showed the extract induced cytotoxicity in MDA-MB-231 cells and MCF-7 cells with IC50 values of 30 and 15 μg/mL, respectively. The extract showed significant toxicity towards both cell lines, with low toxicity to normal breast cells (MCF-10A). The cytotoxic effects on the cells were further confirmed by the NR uptake, antiproliferative and LDH release assays. Bioactive analyses revealed that many bioactives were present in the extract although butylated hydroxytoluene, a potent antioxidant, was the most abundant with 44.65%. M. indica extract appears to be more cytoxic to both estrogen positive and negative breast cancer cell lines than to normal breast cells. Synergistic effects of its antioxidant bioactives could have contributed to the cytotoxic effects of the extract. The extract of M. indica, therefore, has potential anticancer activity against breast cancer cells. This potential is worth studying further, and could have implications on future studies and eventually management of human breast cancers.
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2014-01-01
Background Waterlily Mango (Mangifera indica L.) is thought to be antioxidant-rich, conferred by its functional phytochemicals. Methods The potential anticancer effects of the ethanolic kernel extract on breast cancer cells (MDA-MB-231 and MCF-7) using MTT, anti-proliferation, neutral red (NR) uptake and lactate dehydrogenase (LDH) release assays were evaluated. Cytological studies on the breast cancer cells were also conducted, and phytochemical analyses of the extract were carried out to determine the likely bioactive compounds responsible for such effects. Results Results showed the extract induced cytotoxicity in MDA-MB-231 cells and MCF-7 cells with IC50 values of 30 and 15 μg/mL, respectively. The extract showed significant toxicity towards both cell lines, with low toxicity to normal breast cells (MCF-10A). The cytotoxic effects on the cells were further confirmed by the NR uptake, antiproliferative and LDH release assays. Bioactive analyses revealed that many bioactives were present in the extract although butylated hydroxytoluene, a potent antioxidant, was the most abundant with 44.65%. Conclusions M. indica extract appears to be more cytoxic to both estrogen positive and negative breast cancer cell lines than to normal breast cells. Synergistic effects of its antioxidant bioactives could have contributed to the cytotoxic effects of the extract. The extract of M. indica, therefore, has potential anticancer activity against breast cancer cells. This potential is worth studying further, and could have implications on future studies and eventually management of human breast cancers. PMID:24962691
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Kim, Jong H.; Chueh, Chu-Chen; Williams, Spencer T.; ...
2015-09-24
Here in this work, we describe a room-temperature, solution-processable organic electron extraction layer (EEL) for high-performance planar heterojunction perovskite solar cells (PHJ PVSCs). This EEL is composed of a bilayered fulleropyrrolidinium iodide (FPI)-polyethyleneimine (PEIE) and PC 61BM, which yields a promising power conversion efficiency (PCE) of 15.7% with insignificant hysteresis. We reveal that PC 61BM can serve as a surface modifier of FPI-PEIE to simultaneously facilitate the crystallization of perovskite and the charge extraction at FPI-PEIE/CH 3NH 3PbI 3 interface. Furthermore, the FPI-PEIE can also tune the work function of ITO and dope PC 61BM to promote the efficient electronmore » transport between ITO and PC 61BM. Based on the advantages of room-temperature processability and decent electrical property of FPI-PEIE/PC 61BM EEL, a high-performance flexible PVSC with a PCE ~10% is eventually demonstrated. Lastly, this study shows the potential of low-temperature processed organic EEL to replace transition metal oxide-based interlayers for highly printing compatible PVSCs with high-performance.« less
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Balalakshmi, Chinnasamy; Gopinath, Kasi; Govindarajan, Marimuthu; Lokesh, Ravi; Arumugam, Ayyakannu; Alharbi, Naiyf S; Kadaikunnan, Shine; Khaled, Jamal M; Benelli, Giovanni
2017-08-01
The impact of green-fabricated gold nanoparticles on plant cells and non-target aquatic species is scarcely studied. In this research, we reported an environment friendly technique for the synthesis of gold nanoparticles (Au NPs) using the Sphaeranthus indicus leaf extract. The formation of the metal NPs was characterized by UV-Visible and FT-IR spectroscopy, XRD, SEM and TEM analyses. The UV-Visible spectra of Au NPs showed a surface plasmon resonance peak at 531nm. FT-IR analysis indicated functional bio-molecules associated with Au NPs formation. The crystalline nature of Au nanoparticles was confirmed by their XRD diffraction pattern. TEM revealed the spherical shape with a mean particle size of 25nm. Au NPs was tested at 0, 1, 3, 5, 7 and 10% doses in mitotic cell division assays, pollen germination experiments, and in vivo toxicity trials against the aquatic crustacean Artemia nauplii. Au NPs did not show any toxic effects on plant cells and aquatic invertebrates. Notably, Au NPs promoted mitotic cell division in Allium cepa root tip cells and germination of Gloriosa superba pollen grains. Au NPs showed no mortality on A. nauplii, all the tested animals showed 100% survivability. Therefore, these Au NPs have potential applications in the development of pollen germination media and plant tissue culture. Copyright © 2017 Elsevier B.V. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Schoenitzer, Veronika; Universitaet Regensburg, Biochemie I, Universitaetsstrasse 31, D-93053 Regensburg; Eichner, Norbert
Highlights: Black-Right-Pointing-Pointer Dictyostelium produces the 264 kDa myosin chitin synthase of bivalve mollusc Atrina. Black-Right-Pointing-Pointer Chitin synthase activity releases chitin, partly associated with the cell surface. Black-Right-Pointing-Pointer Membrane extracts of transgenic slime molds produce radiolabeled chitin in vitro. Black-Right-Pointing-Pointer Chitin producing Dictyostelium cells can be characterized by atomic force microscopy. Black-Right-Pointing-Pointer This model system enables us to study initial processes of chitin biomineralization. -- Abstract: Several mollusc shells contain chitin, which is formed by a transmembrane myosin motor enzyme. This protein could be involved in sensing mechanical and structural changes of the forming, mineralizing extracellular matrix. Here we report themore » heterologous expression of the transmembrane myosin chitin synthase Ar-CS1 of the bivalve mollusc Atrina rigida (2286 amino acid residues, M.W. 264 kDa/monomer) in Dictyostelium discoideum, a model organism for myosin motor proteins. Confocal laser scanning immunofluorescence microscopy (CLSM), chitin binding GFP detection of chitin on cells and released to the cell culture medium, and a radiochemical activity assay of membrane extracts revealed expression and enzymatic activity of the mollusc chitin synthase in transgenic slime mold cells. First high-resolution atomic force microscopy (AFM) images of Ar-CS1 transformed cellulose synthase deficient D. discoideumdcsA{sup -} cell lines are shown.« less
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NASA Astrophysics Data System (ADS)
Hao, Jing-Yu; Xu, Ying; Zhang, Yu-Pei; Chen, Shu-Fen; Li, Xing-Ao; Wang, Lian-Hui; Huang, Wei
2015-04-01
Au nanoparticles (NPs) mixed with a majority of bone-like, rod, and cube shapes and a minority of irregular spheres, which can generate a wide absorption spectrum of 400 nm-1000 nm and three localized surface plasmon resonance peaks, respectively, at 525, 575, and 775 nm, are introduced into the hole extraction layer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) to improve optical-to-electrical conversion performances in polymer photovoltaic cells. With the doping concentration of Au NPs optimized, the cell performance is significantly improved: the short-circuit current density and power conversion efficiency of the poly(3-hexylthiophene): [6,6]-phenyl-C60-butyric acid methyl ester cell are increased by 20.54% and 21.2%, reaching 11.15 mA·cm-2 and 4.23%. The variations of optical, electrical, and morphology with the incorporation of Au NPs in the cells are analyzed in detail, and our results demonstrate that the cell performance improvement can be attributed to a synergistic reaction, including: 1) both the localized surface plasmon resonance- and scattering-induced absorption enhancement of the active layer, 2) Au doping-induced hole transport/extraction ability enhancement, and 3) large interface roughness-induced efficient exciton dissociation and hole collection. Project supported by the National Basic Research Program of China (Grant Nos. 2015CB932202 and 2012CB933301), the National Natural Science Foundation of China (Grant Nos. 61274065, 51173081, 61136003, BZ2010043, 51372119, and 51172110), the Science Fund from the Ministry of Education of China (Grant No. IRT1148), the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20113223110005), the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions (Grant No. YX03001), and the National Synergistic Innovation Center for Advanced Materials and the Synergetic Innovation Center for Organic Electronics and Information Displays, China.
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Shrink-wrapped isosurface from cross sectional images
Choi, Y. K.; Hahn, J. K.
2010-01-01
Summary This paper addresses a new surface reconstruction scheme for approximating the isosurface from a set of tomographic cross sectional images. Differently from the novel Marching Cubes (MC) algorithm, our method does not extract the iso-density surface (isosurface) directly from the voxel data but calculates the iso-density point (isopoint) first. After building a coarse initial mesh approximating the ideal isosurface by the cell-boundary representation, it metamorphoses the mesh into the final isosurface by a relaxation scheme, called shrink-wrapping process. Compared with the MC algorithm, our method is robust and does not make any cracks on surface. Furthermore, since it is possible to utilize lots of additional isopoints during the surface reconstruction process by extending the adjacency definition, theoretically the resulting surface can be better in quality than the MC algorithm. According to experiments, it is proved to be very robust and efficient for isosurface reconstruction from cross sectional images. PMID:20703361
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Quantitative Magnetic Separation of Particles and Cells Using Gradient Magnetic Ratcheting.
Murray, Coleman; Pao, Edward; Tseng, Peter; Aftab, Shayan; Kulkarni, Rajan; Rettig, Matthew; Di Carlo, Dino
2016-04-13
Extraction of rare target cells from biosamples is enabling for life science research. Traditional rare cell separation techniques, such as magnetic activated cell sorting, are robust but perform coarse, qualitative separations based on surface antigen expression. A quantitative magnetic separation technology is reported using high-force magnetic ratcheting over arrays of magnetically soft micropillars with gradient spacing, and the system is used to separate and concentrate magnetic beads based on iron oxide content (IOC) and cells based on surface expression. The system consists of a microchip of permalloy micropillar arrays with increasing lateral pitch and a mechatronic device to generate a cycling magnetic field. Particles with higher IOC separate and equilibrate along the miropillar array at larger pitches. A semi-analytical model is developed that predicts behavior for particles and cells. Using the system, LNCaP cells are separated based on the bound quantity of 1 μm anti-epithelial cell adhesion molecule (EpCAM) particles as a metric for expression. The ratcheting cytometry system is able to resolve a ±13 bound particle differential, successfully distinguishing LNCaP from PC3 populations based on EpCAM expression, correlating with flow cytometry analysis. As a proof-of-concept, EpCAM-labeled cells from patient blood are isolated with 74% purity, demonstrating potential toward a quantitative magnetic separation instrument. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Zhu, Weili; Xue, Xiaoping; Zhang, Zhanjun
2016-10-01
Polygonum multiflorum is a popular Chinese herbal medicine with various pharmacological functions. In this study, the ultrasonic-assisted extraction condition, structural characterization and antitumor activity of a polysaccharide from roots of P. multiflorum were investigated. The ultrasonic-assisted extraction condition was optimized by single-factor experiments and response surface methodology. Results showed that the maximum extraction yield (5.49%) was obtained at ultrasonic power 158W, extraction temperature 62°C, extraction time 80min and ratio of water to material 20mL/g. The obtained crude polysaccharides were further purified to afford a neutral and an acidic fraction. The structure of the main neutral polysaccharide (named PPS with molecular weight of 3.26×10(5)Da) was characterized as a linear (1→6)-α-d-glucan by gas chromatography, Fourier transform-infrared spectroscopy, methylation analysis, 1D and 2D nuclear magnetic resonance. At the concentration of 400μg/mL, the inhibitory ratios of PPS on HepG-2 and BGC-823 cells were 53.35% and 38.58%, respectively. Results suggested this polysaccharide could be a potential natural antitumor agent. Copyright © 2016 Elsevier B.V. All rights reserved.
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Transparent electrodes in silicon heterojunction solar cells: Influence on contact passivation
Tomasi, Andrea; Sahli, Florent; Seif, Johannes Peter; ...
2015-10-26
Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally capped by an n-type transparent conductive oxide, which is primarily needed for carrier extraction. Earlier, it has been demonstrated that the mere presence of such oxides can affect the carrier recombination in the crystalline silicon absorber. Here, we present a detailed investigation of the impact of this phenomenon on both the electron and hole collecting sides, including its consequences for the operating voltages of silicon heterojunction solarmore » cells. As a result, we define guiding principles for improved passivating contact design for high-efficiency silicon solar cells.« less
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Transparent electrodes in silicon heterojunction solar cells: Influence on contact passivation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tomasi, Andrea; Sahli, Florent; Seif, Johannes Peter
Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally capped by an n-type transparent conductive oxide, which is primarily needed for carrier extraction. Earlier, it has been demonstrated that the mere presence of such oxides can affect the carrier recombination in the crystalline silicon absorber. Here, we present a detailed investigation of the impact of this phenomenon on both the electron and hole collecting sides, including its consequences for the operating voltages of silicon heterojunction solarmore » cells. As a result, we define guiding principles for improved passivating contact design for high-efficiency silicon solar cells.« less
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Lipid extraction from isolated single nerve cells
NASA Technical Reports Server (NTRS)
Krasnov, I. V.
1977-01-01
A method of extracting lipids from single neurons isolated from lyophilized tissue is described. The method permits the simultaneous extraction of lipids from 30-40 nerve cells and for each cell provides equal conditions of solvent removal at the conclusion of extraction.
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NASA Astrophysics Data System (ADS)
Wei, Ming-Tzo; Hua, Kuo-Feng; Hsu, Jowey; Karmenyan, Artashes; Hsu, Hsien-Yeh; Chiou, Arthur
2006-08-01
Lipopolysaccharide (LPS) is one of the cell wall components of Gram-positive bacteria recognized by and interacted with receptor proteins such as CD14 on macrophage cells. Such a process plays an important role in our innate immune system. In this paper, we report the application of optical tweezers (λ = 1064nm Gaussian beam focused by a water-immersed objective lens with N.A. = 1.0) to the study of the dynamics of the binding of a LPS-coated polystyrene particle (diameter = 1.5μm) onto the plasma membrane of a macrophage cell. We demonstrated that the binding rate increased significantly when the macrophage cell was pre-treated with the extract of Reishi polysaccharides (EORP) which has been shown to enhance the cell surface expression of CD14 (receptor of LPS) on macrophage cells.
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NASA Astrophysics Data System (ADS)
Choi, Yong Hyun; Min, Junhong; Cho, Sungbo
2015-06-01
Analysis on the interaction between proteins and cells is required for understanding the cellular behaviour and response. In this article, we characterized the adhesion and growth of 293/GFP cells on fetal bovine serum (FBS) coated indium tin oxide (ITO) electrode. Using optical and electrochemical measurement, it was able to detect the adsorption of the protein on the surface of the ITO electrode dependent on the concentration of the protein in the immersing solution or the immersing time. An increase in the amount of the adsorbed serum protein resulted in a decrease in anodic peak current and an increase in the charge transfer resistance extracted from the equivalent circuit fitting analysis. More cells adhered and proliferated on the ITO electrode which was pre-immersed in FBS medium rather than bare electrode. The effect of the FBS on cell behaviors was reflected in the impedance monitoring of cells at 21.5 kHz.
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Pollio, Antonino; Zarrelli, Armando; Romanucci, Valeria; Di Mauro, Alfredo; Barra, Federica; Pinto, Gabriele; Crescenzi, Elvira; Roscetto, Emanuela; Palumbo, Giuseppe
2016-03-23
The methanol extracts of the aerial part of four ethnomedicinal plants of Mediterranean region, two non-seed vascular plants, Equisetum hyemale L. and Phyllitis scolopendrium (L.) Newman, and two Spermatophyta, Juniperus communis L. (J. communis) and Cotinus coggygria Scop. (C. coggygria), were screened against four human cells lines (A549, MCF7, TK6 and U937). Only the extracts of J. communis and C. coggygria showed marked cytotoxic effects, affecting both cell morphology and growth. A dose-dependent effect of these two extracts was also observed on the cell cycle distribution. Incubation of all the cell lines in a medium containing J. communis extract determined a remarkable accumulation of cells in the G2/M phase, whereas the C. coggygria extract induced a significant increase in the percentage of G1 cells. The novelty of our findings stands on the observation that the two extracts, consistently, elicited coherent effects on the cell cycle in four cell lines, independently from their phenotype, as two of them have epithelial origin and grow adherent and two are lymphoblastoid and grow in suspension. Even the expression profiles of several proteins regulating cell cycle progression and cell death were affected by both extracts. LC-MS investigation of methanol extract of C. coggygria led to the identification of twelve flavonoids (compounds 1-11, 19) and eight polyphenols derivatives (12-18, 20), while in J. communis extract, eight flavonoids (21-28), a α-ionone glycoside (29) and a lignin (30) were found. Although many of these compounds have interesting individual biological activities, their natural blends seem to exert specific effects on the proliferation of cell lines either growing adherent or in suspension, suggesting potential use in fighting cancer.
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Shahraki, Samira; Khajavirad, Abolfazl; Shafei, Mohammad Naser; Mahmoudi, Mahmoud; Tabasi, Nafisa Sadat
2016-01-01
Medicinal plants are noted for their many advantages including the ability to treat diseases such as cancer. In this study, we examined the antitumor effect of the medicinal plant Nigella sativa on the morphology, survival, and apoptosis of ACHN (human renal adenocarcinoma) and GP-293 (normal renal epithelial) cell lines. From a hydroalcoholic extract of N. sativa, n-hexane and ethyl acetate fractions were extracted. Cells were treated with various concentrations of total hydroalcholic extract and n-hexane and ethyl acetate fractions; cell viability, morphological changes, and apoptosis were then determined. Results were presented as mean ± standard error of the mean (SEM). One-way analysis of variance (ANOVA) was applied for the statistical analysis of the data. The total extract and the fractions in a dose- and time-dependent manner reduced the cell viability in ACHN with no effect on the GP-293 cell line. In addition, the total extract resulted in more morphological changes in the ACHN cells compared to the GP-293 cells. The effect of the total extract in inducing apoptosis after 48 hours in the ACHN cell line was greater than in GP-293. In addition, the effect of the two fractions was lower than the total extract at all used concentrations. Therefore, the effect of total extract and n-hexane and ethyl acetate fractions of N. sativa on cell viability and apoptosis in the ACHN cell line is greater than in the GP-293 cell line. However, the effect of the total extract is higher than either of the two fractions on their own.
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Differentiation of human adipose tissue stem cells using extracts of rat cardiomyocytes.
Gaustad, Kristine G; Boquest, Andrew C; Anderson, Brent E; Gerdes, A Martin; Collas, Philippe
2004-02-06
We report the differentiation of human adipose tissue stem cells (ATSCs) to take on cardiomyocyte properties following transient exposure to a rat cardiomyocyte extract. Reversibly permeabilized ATSCs were incubated for 1h in a nuclear and cytoplasmic extract of rat cardiomyocytes, resealed with CaCl(2), and cultured. Three weeks after exposure to extract, ATSCs expressed several cardiomyocyte markers including sarcomeric alpha-actinin, desmin, and cardiac troponin I, and displayed targeted expression of the gap junction protein connexin 43. Formation of binucleated and striated cells, and spontaneous beating in culture were also observed. A low proportion of intact ATSCs exposed to the extract also showed signs of alpha-actinin and connexin 43 expression. Additional evidence of differentiation was provided by induction of expression of nuclear lamin A/C, a marker of terminally differentiated cells, and a remarkable increase in cell cycle length. Together with our previous data, this study suggests that alteration of cell fate using cellular extracts may be applied to multiple cell types. Cell extracts may also prove useful for investigating the molecular mechanisms of stem cell differentiation.
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Erenler, Ramazan; Pabuccu, Koksal; Yaglioglu, Ayse Sahin; Demirtas, Ibrahim; Gul, Fatih
2016-03-01
In this study, the effect of Mougeotia nummuloides and Spirulina major on Vero cells (African green monkey kidney), C6 cells (rat brain tumor cells) and HeLa cells (human uterus carcinoma) was investigated in vitro. The antiproliferative effect of the methanol extract of M. nummuloides and S. major compared with 5-fluorourasil (5-FU) and cisplatin was tested at various concentrations using the BrdU Cell Proliferation ELISA. Both M. nummuloides and S. major extracts significantly inhibited the proliferation of Vero, HeLa and C6 cancer cell lines with IC50 and IC75 values. The M. nummuloides extract exhibited higher activity than 5-FU and cisplatin on Vero and C6 cells at high concentrations. The S. major extract revealed better antifproliferative activity than standards against Vero cells at 500 μg/mL. The compounds of methanol extracts were determined by GC-MS after the silylation process. Trehalose, monostearin and 1-monopalmitin were detected as major products in the M. nummuloides extract where as in the S. major extract; monostearin, 1-monopalmitin and hexyl alcohol were the main constituents.
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Magnetic capture of polydopamine-encapsulated Hela cells for the analysis of cell surface proteins.
Liu, Yiying; Yan, Guoquan; Gao, Mingxia; Zhang, Xiangmin
2018-02-10
A novel method to characterize cell surface proteins and complexes has been developed. Polydopamine (PDA)-encapsulated Hela cells were prepared for plasma membrane proteome research. Since the PDA protection, the encapsulated cells could be maintained for more than two weeks. Amino groups functionalized magnetic nanoparticles were also used for cell capture by the reaction with the PDA coatings. Plasma membrane fragments were isolated and enriched with assistance of an external magnetic field after disruption of the coated cells by ultrasonic treatment. Plasma membrane proteins (PMPs) and complexes were well preserved on the fragments and identified by shot-gun proteomic analytical strategy. 385 PMPs and 1411 non-PMPs were identified using the method. 85.2% of these PMPs were lipid-raft associated proteins. Ingenuity Pathway Analysis was employed for bio-information extraction from the identified proteins. It was found that 653 non-PMPs had interactions with 140 PMPs. Among them, epidermal growth factor receptor and its complexes, and a series of important pathways including STAT3 pathway were observed. All these results demonstrated that the new approach is of great importance in applying to the research of physiological function and mechanism of the plasma membrane proteins. This work developed a novel strategy for the proteomic analysis of cell surface proteins. According to the results, 73.3% of total identified proteins were lipid-raft associated proteins, which imply that the proposed method is of great potential in the identification of lipid-raft associated proteins. In addition, a series of protein-protein interactions and pathways related to Hela cells were pointed out. All these results demonstrated that our proposed approach is of great importance and could well be applied to the physiological function and mechanism research of plasma membrane proteins. Copyright © 2017 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Kumar, S.; Panigrahi, D.; Dhar, A.
2018-03-01
Interfacial issues can significantly restrict the performance of photovoltaic devices by exacerbating the charge recombination channels, macroscopic phase separation, and providing a non-ideal contact for selective extraction of charges particularly in photovoltaic devices using organic and inorganic materials together. Organic interfacial modifiers (IMs) are often used to mitigate these issues by modifying the organic-inorganic interface. In order to extricate the role of these IMs on the photovoltaic performance we have made a comprehensive study on the application of perylene-based and fullerene small molecules having different molecular origin as organic IMs on ZnO electron extracting layers in inverted BHJs photovoltaic devices. We report an elaborate study on the electronic and surface altering properties of these IMs and correlated their effect on the different PV performance parameters of the inverted BHJ solar cells employing P3HT: PCBM photoactive layer. Our investigations demonstrate the role of these organic IMs in reducing the ZnO cathode work function and increasing its electron transportation property along with the passivation of superficial traps states present on ZnO which helps in selective extraction of charge carriers from the devices and minimize the recombination losses. These different aspects of IMs compete and their balanced effect decides the final outcome. As a result, we obtain a substantial improvement in the device performance with power conversion efficiency (PCE) of 3.0% for the C70/ZnO cathode device which shows over 60% improvement in contrast to the devices without any ZnO surface modification. The present investigation intents to exhibit the feasibility of vacuum sublimated organic small molecules in performance improvement in BHJ solar cells utilizing the ZnO ETLs and contrast their efficacy for the purpose rather than setting any benchmark device performance although the efficiencies obtained are typical for the active layer used in the study.
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The Effect of Detergents on the Morphology and Immunomodulatory Activity of Malassezia furfur
Kim, Su-Han; Ko, Hyun-Chang; Kwon, Kyung-Sool; Oh, Chang-Keun
2009-01-01
Background Several workers have found that Malassezia are capable of suppressing cytokine release and downregulating the phagocytic function of monocytes. But lipid-depleted Malassezia furfur (M. furfur) extracts have also been shown to induce increased production of TNF-α, IL-6 and IL-1β in monocytes. We thought that the detergents in shampoos or soaps could change the composition of the lipid in the M. furfur cell wall. Objective We studied whether detergents affect the morphology of M. furfur and if the inflammatory cytokine profiles change in the monocytes treated with detergent-treated M. furfur. Methods Commonly used detergents such as sodium lauryl sulfate, ammonium lauryl sulfate and tween-80 were respectively added to the modified Leeming-Notman's media. M. furfur was cultivated in each media (detergent-added or untreated). Thereafter, the surface morphology of the yeast was evaluated by scanning and transmission electron microscopy. The cytokine profiles of monocytes, which were treated by M. furfur with or without detergents, were also evaluated. Results The detergent-treated M. furfur were similar to the lipid-extracted form of M. furfur on the electron microscopic study, with a recessed, withered surface and with thinner and rather electron transparent cell walls than the detergent-untreated M. furfur. The levels of TNF-α were higher in monocytes treated with detergent-treated Malassezia than that in the monocytes treated with the detergent-untreated Malassezia (p<0.05). Conclusion According to the findings in this study, it could be inferred that the detergents in shampoos or soaps affect the lipid layers of the Malassezia cell wall and these lipid-extracted Malassezia induce or aggravate some inflammatory conditions. But to correlate the relationship between detergents and Malassezia-associated diseases, in vivo experiments that will focus on short-term contact with detergents in real life conditions should be done. PMID:20523770
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Comín, Romina; Cid, Mariana P; Grinschpun, Luciano; Oldani, Carlos; Salvatierra, Nancy A
2017-04-26
In clinical orthopedics, a critical problem is the bone tissue loss produced by a disease or injury. The use of composites from titanium and hydroxyapatite for biomedical applications has increased due to the resulting advantageous combination of hydroxyapatite bioactivity and favorable mechanical properties of titanium. Powder metallurgy is a simple and lower-cost method that uses powder from titanium and hydroxyapatite to obtain composites having hydroxyapatite phases in a metallic matrix. However, this method has certain limitations arising from thermal decomposition of hydroxyapatite in the titanium-hydroxyapatite system above 800°C. We obtained a composite from titanium and bovine hydroxyapatite powders sintered at 800°C and evaluated its bioactivity and cytocompatibility according to the ISO 10993 standard. Surface analysis and bioactivity of the composite was evaluated by X-ray diffraction and SEM. MTT assay was carried out to assess cytotoxicity on Vero and NIH3T3 cells. Cell morphology and cell adhesion on the composite surface were analyzed using fluorescence and SEM. We obtained a porous composite with hydroxyapatite particles well integrated in titanium matrix which presented excellent bioactivity. Our data did not reveal any toxicity of titanium-hydroxyapatite composite on Vero or NIH3T3 cells. Moreover, extracts from composite did not affect cell morphology or density. Finally, NIH3T3 cells were capable of adhering to and proliferating on the composite surface. The composite obtained displayed promising biomedical applications through the simple method of powder metallurgy. Additionally, these findings provide an in vitro proof for adequate biocompatibility of titanium-hydroxyapatite composite sintered at 800°C.
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Giaouris, Efstathios; Samoilis, Georgios; Chorianopoulos, Nikos; Ercolini, Danilo; Nychas, George-John
2013-03-01
In the present study, the proteome of a strain of S. enterica serovar Enteritidis PT4, grown either as biofilm on stainless steel surface or as free-floating (planktonic) in Brain Heart (BH) broth, was investigated in order to detect the strong differences in whole-cell protein expression patterns between the two growth styles. The proteins extracted from both types of cells were subjected to 2-D PAGE, followed by in-gel tryptic digestion, extraction, subsequent MALDI-TOF mass spectrometry (MS) analysis and finally database searches for protein identification. Using this approach, 30 proteins were identified as differentially expressed between the two growth modes on an "on-off" basis, that is, proteins that were detected in one case but not in the other. In particular, 20 and 10 proteins were identified in biofilm and planktonic-grown cells, respectively. The group of proteins whose expression was visible only during biofilm growth included proteins involved in global regulation and stress response (ArcA, BtuE, Dps, OsmY, SspA, TrxA, YbbN and YhbO), nutrient transport (Crr, DppA, Fur and SufC), degradation and energy metabolism (GcvT, GpmA, RibB), detoxification (SseA and YibF), DNA metabolism (SSB), curli production (CsgF), and murein synthesis (MipA). To summarize, this study demonstrates that biofilm growth of S. Enteritidis causes distinct changes in protein expression and offers valuable new data regarding some of the proteins presumably involved in this process. The putative role of these proteins in the maintenance of a biofilm community in Salmonella and other bacteria is discussed. Copyright © 2012 Elsevier B.V. All rights reserved.
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Wong, Kaitlyn E; Mora, Maria C; Sultana, Nazneen; Moriarty, Kevin P; Arenas, Richard B; Yadava, Nagendra; Schneider, Sallie S; Tirabassi, Michael V
2018-06-01
Outcomes of children with high grade neuroblastoma remain poor despite multi-agent chemotherapy regimens. Rhodiola crenulata extracts display anti-neoplastic properties against several cancers including breast cancer, melanoma, and glioblastoma. In this study, we evaluated the anti-neoplastic potential of Rhodiola crenulata extracts on human neuroblastoma cells. Through this work, cell viability and proliferation were evaluated following treatments with ethanol (vehicle control) or Rhodiola crenulata extract in neuroblastoma, NB-1691 or SK-N-AS cells, in vitro. HIF-1 transcriptional activity was evaluated using a dual luciferase assay. Quantitative real-time polymerase chain reaction was utilized to assess the expression of HIF-1 targets. Selected metabolic intermediates were evaluated for their ability to rescue cells from Rhodiola crenulata extract-induced death. Lactate dehydrogenase, pyruvate kinase, and pyruvate dehydrogenase activities and NAD + /NADH levels were assayed in vehicle and Rhodiola crenulata extract-treated cells. The effects of Rhodiola crenulata extracts on metabolism were assessed by respirometry and metabolic phenotyping/fingerprinting. Our results revealed striking cytotoxic effects upon Rhodiola crenulata extract treatment, especially prominent in NB-1691 cells. As a greater response was observed in NB-1691 cells therefore it was used for remaining experiments. Upon Rhodiola crenulata extract treatment, HIF-1 transcriptional activity was increased. This increase in activity correlated with changes in HIF-1 targets involved in cellular metabolism. Serendipitously, we observed that addition of pyruvate protected against the cytotoxic effects of Rhodiola crenulata extracts. Therefore, we focused on the metabolic effects of Rhodiola crenulata extracts on NB-1691 cells. We observed that while the activities of pyruvate kinase and pyruvate dehydrogenase activities were increased, the activity of lactate dehydrogenase activity was decreased upon Rhodiola crenulata extract treatment. We also noted a decline in the total NAD pool following Rhodiola crenulata extract treatment. This correlated with decreased cellular respiration and suppressed utilization of carbon substrates. Through this work, we observed significant cytotoxic effects of Rhodiola crenulata extract treatment upon treatment on NB-1691 cells, a human neuroblastoma cell line with MYCN amplification. Our studies suggest that these cytotoxic effects could be secondary to metabolic effect induced by treatment with Rhodiola crenulata extract.
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Development of green extraction processes for Nannochloropsis gaditana biomass valorization.
Sánchez-Camargo, Andrea Del Pilar; Pleite, Natalia; Mendiola, José Antonio; Cifuentes, Alejandro; Herrero, Miguel; Gilbert-López, Bienvenida; Ibáñez, Elena
2018-04-23
In the present work, the valorization of Nannochloropsis gaditana biomass is proposed within the concept of biorefinery. To this aim, high-pressure homogenization (HPH) was used to break down the strong cell wall and supercritical fluid extraction (SFE) with pure CO 2 was applied as a first step to extract valuable compounds (such as non-polar lipids and pigments). Extraction of the remaining residue for the recovery of bioactive compounds was studied by means of an experimental design based on response surface methodology (RSM) employing pressurized liquid extraction (PLE) with green solvents such as water and ethanol. Optimum extract was achieved with pure ethanol at 170°C for 20 min, providing an important antioxidant capacity (0.72 ± 0.03 mmol trolox eq g -1 extract). Complete chemical characterization of the optimum extract was carried out by using different chromatographic methods such as reverse-phase high-performance liquid chromatography with diode array detection (RP-HPLC-DAD), normal-phase HPLC with evaporative light scattering detection (NP-HPLC-ELSD) and gas chromatography coupled to mass spectrometry detection (GC-MS); carotenoids (e.g. violaxanthin), chlorophylls and polar lipids were the main compounds observed while palmitoleic, palmitic, myristic acids and the polyunsaturated eicosapentanoic (EPA) acid were the predominant fatty acids in all PLE extracts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Cao, Yan; Li, Ying-Hua; Lv, Di-Ya; Chen, Xiao-Fei; Chen, Lang-Dong; Zhu, Zhen-Yu; Chai, Yi-Feng; Zhang, Jun-Ping
2016-07-01
Identification of bioactive compounds directly from complex herbal extracts is a key issue in the study of Chinese herbs. The present study describes the establishment and application of a sensitive, efficient, and convenient method based on surface plasmon resonance (SPR) biosensors for screening active ingredients targeting tumor necrosis factor receptor type 1 (TNF-R1) from Chinese herbs. Concentration-adjusted herbal extracts were subjected to SPR binding assay, and a remarkable response signal was observed in Rheum officinale extract. Then, the TNF-R1-bound ingredients were recovered, enriched, and analyzed by UPLC-QTOF/MS. As a result, physcion-8-O-β-D-monoglucoside (PMG) was identified as a bioactive compound, and the affinity constant of PMG to TNF-R1 was determined by SPR affinity analysis (K D = 376 nM). Pharmacological assays revealed that PMG inhibited TNF-α-induced cytotoxicity and apoptosis in L929 cells via TNF-R1. Although PMG was a trace component in the chemical constituents of the R. officinale extract, it had considerable anti-inflammatory activities. It was found for the first time that PMG was a ligand for TNF receptor from herbal medicines. The proposed SPR-based screening method may prove to be an effective solution to analyzing bioactive components of Chinese herbs and other complex drug systems. Graphical abstract Scheme of the method based on SPR biosensor for screening and recovering active ingredients from complex herbal extracts and UPLC-MS for identifying them. Scheme of the method based on SPR biosensor for screening and recovering active ingredients from complex herbal extracts and UPLC-MS for identifying them.
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Carboxylic and dicarboxylic acids extracted from crushed magnesium oxide single crystals
NASA Technical Reports Server (NTRS)
Freund, F.; Gupta, A. D.; Kumar, D.
1999-01-01
Carboxylic and dicarboxylic acids (glycolic, oxalic, malonic and succinic) have been extracted with tetrahydrofuran (THF) and H2O from large synthetic MgO crystals, crushed to a medium fine powder. The extracts were characterized by infrared spectroscopy and 1H-NMR. The THF extracts were derivatized with tert-butyldimethylsilyl (t-BDMS) for GC-MS analysis. A single crystal separated from the extract was used for an x-ray structure analysis, giving the monoclinic unit cell, space group P21/c with ao = 5.543 A, bo = 8.845 A, co = 5.086 A, and beta = 91.9 degrees, consistent with beta-succinic acid, HOOC(CH2)COOH. The amount of extracted acids is estimated to be of the order of 0.1 to 0.5 mg g-1 MgO. The MgO crystals from which these organic acids were extracted grew from the 2860 degrees C hot melt, saturated with CO/CO2 and H2O, thereby incorporating small amounts of the gaseous components to form a solid solution (ss) with MgO. Upon cooling, the ss becomes supersaturated, causing solute carbon and other solute species to segregate not only to the surface but also internally, to dislocations and subgrain boundaries. The organic acids extracted from the MgO crystals after crushing appear to derive from these segregated solutes that formed C-C, C-H and C-O bonds along dislocations and other defects in the MgO structure, leading to entities that can generically be described as (HxCyOz)n-. The processes underlying the formation of these precursors are fundamental in nature and expected to be operational in any minerals, preferentially those with dense structures, that crystallized in H2O-CO2-laden environments. This opens the possibility that common magmatic and metamorphic rocks when weathering at the surface of a tectonically active planet like Earth may be an important source of abiogenically formed complex organic compounds.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansson, J.; Keyse, S.M.; Lindahl, T.
Whole cell extracts from human lymphoid cell lines can perform in vitro DNA repair synthesis in plasmids damaged by agents including UV or cis-diamminedichloroplatinum(II) (cis-DDP). Extracts from xeroderma pigmentosum (XP) cells are defective in repair synthesis. We have now studied in vitro DNA repair synthesis using extracts from lymphoblastoid cell lines representing four human hereditary syndromes with increased sensitivity to DNA-damaging agents. Extracts of cell lines from individuals with the sunlight-sensitive disorders dysplastic nevus syndrome or Cockayne's syndrome (complementation groups A and B) showed normal DNA repair synthesis in plasmids with UV photoproducts. This is consistent with in vivo measurementsmore » of the overall DNA repair capacity in such cell lines. A number of extracts were prepared from two cell lines representing the variant form of XP (XP-V). Half of the extracts prepared showed normal levels of in vitro DNA repair synthesis in plasmids containing UV lesions, but the remainder of the extracts from the same cell lines showed deficient repair synthesis, suggesting the possibility of an unusually labile excision repair protein in XP-V. Fanconi's anemia (FA) cells show cellular hypersensitivity to cross-linking agents including cis-DDP. Extracts from cell lines belonging to two different complementation groups of FA showed normal DNA repair synthesis in plasmids containing cis-DDP or UV adducts. Thus, there does not appear to be an overall excision repair defect in FA, but the data do not exclude a defect in the repair of interstrand DNA cross-links.« less
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Seok, Jin Kyung; Suh, Hwa-Jin
2014-01-01
Ultraviolet radiation (UV) is a major cause of photoaging, which also involves inflammatory cytokines and matrix metalloproteinases (MMP). The present study was undertaken to examine the UVB-protecting effects of yellow-colored plant extracts in cell-based assays. HaCaT keratinocytes were exposed to UVB in the absence or presence of plant extracts, and resulting changes in cell viability and inflammatory cytokine expression were measured. Of the plant extracts tested, Gardenia jasminoides extract showed the lowest cytotoxicity and dose-dependently enhanced the viabilities of UVB-exposed cells. Gardenia jasminoides extract also attenuated the mRNA expressions of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in HaCaT cells stimulated by UVB. Conditioned medium from UVB-exposed HaCaT cells was observed to stimulate MMP-1 protein expression in human dermal fibroblasts, and this effect was much smaller for the conditioned medium of HaCaT cells exposed to UVB in the presence of Gardenia jasminoides extract. Gardenia jasminoides extract also exhibited antioxidative and antiapoptotic effects in HaCaT cells exposed to UVB. These results indicated that UVB-induced injury and inflammatory responses of skin cells can be attenuated by yellow-colored plant extracts, such as Gardenia jasminoides extract. PMID:24711853
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DEGRADATION OF ERGOTHIONEINE BY CELL-FREE EXTRACTS OF ALCALIGENES FAECALIS II.
Booth, James S.; Appleman, Milo D.
1963-01-01
Booth, James S. (University of Southern California, Los Angeles) and Milo D. Appleman. Degradation of ergothioneine by cell-free extracts of Alcaligenes faecalis. II. Production of glutamic acid. J. Bacteriol. 85:654–657. 1963.—On the basis of oxidation and paper chromatographic procedures, glutamic acid was identified as the end product of ergothioneine degradation by cell-free extracts of Alcaligenes faecalis. Hydrogen sulfide and ammonia yields were determined. Several differences between the metabolism of whole cells and cell-free extracts were noted. Cleavage of the imidazole ring by cell-free extracts appeared to be hydrolytic rather than oxidative. PMID:14042946
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Harhaji, Lj; Mijatović, S; Maksimović-Ivanić, D; Stojanović, I; Momcilović, M; Maksimović, V; Tufegdzić, S; Marjanović, Z; Mostarica-Stojković, M; Vucinić, Z; Stosić-Grujicić, S
2008-05-01
Numerous studies have shown immunostimulatory and anti-tumor effects of water and standardized aqueous ethanol extracts derived from the medicinal mushroom, Coriolus versicolor, but the biological activity of methanol extracts has not been examined so far. In the present study we investigated the anti-tumor effect of C. versicolor methanol extract (which contains terpenoids and polyphenols) on B16 mouse melanoma cells both in vitro and in vivo. In vitro treatment of the cells with the methanol extract (25-1600 microg/ml) reduced melanoma cell viability in a dose-dependent manner. Furthermore, in the presence of the methanol extract (200 microg/ml, concentration IC(50)) the proliferation of B16 cells was arrested in the G(0)/G(1) phase of the cell cycle, followed by both apoptotic and secondary necrotic cell death. In vivo methanol extract treatment (i.p. 50 mg/kg, for 14 days) inhibited tumor growth in C57BL/6 mice inoculated with syngeneic B16 tumor cells. Moreover, peritoneal macrophages collected 21 days after tumor implantation from methanol extract-treated animals exerted stronger tumoristatic activity ex vivo than macrophages from control melanoma-bearing mice. Taken together, our results demonstrate that C. versicolor methanol extract exerts pronounced anti-melanoma activity, both directly through antiproliferative and cytotoxic effects on tumor cells and indirectly through promotion of macrophage anti-tumor activity.
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The role of amniotic membrane extract eye drop (AMEED) in in vivo cultivation of limbal stem cells.
Baradaran-Rafii, Alireza; Asl, Niloufar Shayan; Ebrahimi, Marzieh; Jabbehdari, Sayena; Bamdad, Shahram; Roshandel, Danial; Eslani, Medi; Momeni, Maryam
2018-01-01
Limbal stem cell transplantation (LSCT) is the definitive treatment for total limbal stem cell deficiency (LSCD). This study evaluates the anatomical and visual outcomes of a surgical technique supplemented by amniotic membrane extract eye drop (AMEED) for in vivo cultivation of limbal stem cells (LSCs). One small limbal block (2 × 1 mm) harvested from the contralateral healthy eye was transferred to the diseased eye, which had been already covered by cryopreserved amniotic membrane (N = 20). The patients were categorized into case and control groups. AMEED was administered postoperatively only for patients in the case group (N = 14). Sequential penetrating keratoplasty (PKP) was performed in 4 eyes of the case group for optical clarity. Visual acuity, epithelial healing, corneal clarity and regression of conjunctivalization/vascularization were evaluated after surgery. The corneal buttons of post-PKP eyes were evaluated for LSC markers. In the case group, the mean corrected distance visual acuity (CDVA) was 20/400 before surgery, which improved to 20/40 and 20/50 at the last follow-up in eyes with and without PKP, respectively. Epithelial defects healed in all eyes of the case group during 2 weeks after surgery. Corneal conjunctivalization/vascularization regressed dramatically in all patients of the case group 2-3 months after surgery. In PKP cases, all transplanted corneas were clear at the last follow-up. LSC markers were expressed on the surface of all trephined corneal buttons. All eyes in the control group developed persistent epithelial defect. This study suggests that amniotic membrane extract may be helpful for in vivo cultivation of limbal stem cells. Copyright © 2017 Elsevier Inc. All rights reserved.
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Mittal, Amit Kumar; Tripathy, Debabrata; Choudhary, Alka; Aili, Pavan Kumar; Chatterjee, Anupam; Singh, Inder Pal; Banerjee, Uttam Chand
2015-08-01
The present study aims to develop an easy and eco-friendly method for the synthesis of silver nanoparticles using extracts from the medicinal plant, Potentilla fulgens and evaluation of its anticancer and antimicrobial properties. The various parts of P. fulgens were screened and the root extract was found to have the highest potential for the synthesis of nanoparticles. The root extracts were able to quickly reduce Ag(+) to Ag(0) and stabilized the nanoparticles. The synthesis of nanoparticles was confirmed by UV-Visible spectrophotometry and further characterized using Zeta sizer, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). Electron microscopic study showed that the size of the nanoparticle was in the range of 10 to 15 nm and spherical in shape. The studies of phytochemical analysis of nanoparticles indicated that the adsorbed components on the surface of nanoparticles were mainly flavonoid in nature. Furthermore, nanoparticles were evaluated as cytotoxic against various cancer cell lines and 0.2 to 12 μg/mL nanoparticles showed good toxicity. The IC50 value of nanoparticles was found to be 4.91 and 8.23 μg/mL against MCF-7 and U-87 cell lines, respectively. Additionally, the apoptotic effect of synthesized nanoparticles on normal and cancer cells was studied using trypan blue assay and flow-cytometric analysis. The results indicate the synthesized nanoparticle ability to kill cancer cells compared to normal cells. The nanoparticles also exhibited comparable antimicrobial activity against both Gram-positive and Gram-negative bacteria. Copyright © 2015 Elsevier B.V. All rights reserved.
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Skandrani, Ines; Boubaker, Jihed; Bhouri, Wissem; Limem, Ilef; Kilani, Soumaya; Ben Sghaier, Mohamed; Neffati, Aicha; Bouhlel, Ines; Ghedira, Kamel; Chekir-Ghedira, Leila
2010-01-01
The in vitro antiproliferative, apoptotic, and antioxidant activities from leaf extracts of Moricandia arvensis, which are used in traditional cooking and medicines, were investigated. The MTT assay revealed that only TOF (total oligomer flavonoids), ethyl acetate (EA), chloroform (Chl), and petroleum ether (PE) extracts inhibited the proliferation of K562 cells. Apoptosis plays a very important role in the treatment of cancer by promoting the apoptosis of cancer cells and limiting the concurrent death of normal cells. Thus, the possible effects of M. arvensis extracts on the induction of apoptosis in human leukemic cells (K562 cells) were investigated. The electrophoretic analysis of DNA fragmentation confirms that TOF, Chl, PE, and EA extracts provoke DNA fragmentation. Using the lipid peroxidation inhibitory assay, the antioxidant capacity of M. arvensis extracts was evaluated by the ability of each extract to inhibit malondialdehyde formation. It was revealed that EA and TOF extracts are the most active in scavenging the hydroxyl radicals.
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A mathematical model of antibody-dependent cellular cytotoxicity (ADCC).
Hoffman, F; Gavaghan, D; Osborne, J; Barrett, I P; You, T; Ghadially, H; Sainson, R; Wilkinson, R W; Byrne, H M
2018-01-07
Immunotherapies exploit the immune system to target and kill cancer cells, while sparing healthy tissue. Antibody therapies, an important class of immunotherapies, involve the binding to specific antigens on the surface of the tumour cells of antibodies that activate natural killer (NK) cells to kill the tumour cells. Preclinical assessment of molecules that may cause antibody-dependent cellular cytotoxicity (ADCC) involves co-culturing cancer cells, NK cells and antibody in vitro for several hours and measuring subsequent levels of tumour cell lysis. Here we develop a mathematical model of such an in vitro ADCC assay, formulated as a system of time-dependent ordinary differential equations and in which NK cells kill cancer cells at a rate which depends on the amount of antibody bound to each cancer cell. Numerical simulations generated using experimentally-based parameter estimates reveal that the system evolves on two timescales: a fast timescale on which antibodies bind to receptors on the surface of the tumour cells, and NK cells form complexes with the cancer cells, and a longer time-scale on which the NK cells kill the cancer cells. We construct approximate model solutions on each timescale, and show that they are in good agreement with numerical simulations of the full system. Our results show how the processes involved in ADCC change as the initial concentration of antibody and NK-cancer cell ratio are varied. We use these results to explain what information about the tumour cell kill rate can be extracted from the cytotoxicity assays. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Jiang, Zheng; Wang, Hong; Wu, Qi-nan
2015-06-01
To optimize the processing of polysaccharide extraction from Spirodela polyrrhiza. Five factors related to extraction rate of polysaccharide were optimized by the Plackett-Burman design. Based on this study, three factors, including alcohol volume fraction, extraction temperature and ratio of material to liquid, were regarded as investigation factors by Box-Behnken response surface methodology. The effect order of three factors on the extraction rate of polysaccharide from Spirodela polyrrhiza were as follows: extraction temperature, alcohol volume fraction,ratio of material to liquid. According to Box-Behnken response, the best extraction conditions were: alcohol volume fraction of 81%, ratio of material to liquid of 1:42, extraction temperature of 100 degrees C, extraction time of 60 min for four times. Plackett-Burman design and Box-Behnken response surface methodology used to optimize the extraction process for the polysaccharide in this study is effective and stable.
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Keshava, Rohini; Muniyappa, Nagesh; Gope, Rajalakshmi; Ramaswamaiah, Ananthanarayana Saligrama
2016-01-01
Imperata cylindrica, a tall tufted grass which has multiple pharmacological applications is one of the key ingredients in various traditional medicinal formula used in India. Previous reports have shown that I. cylindrica plant extract inhibited cell proliferation and induced apoptosis in various cancer cell lines. To our knowledge, no studies have been published on the effect of I. cylindrica leaf extract on human oral cancers. The present study was undertaken in order to evaluate the anticancer properties of the leaf extract of I. cylindrica using an oral squamous cell carcinoma cell line SCC-9 as an in vitro model system. A methanol extract from dried leaves of I. cylindrica (ICL) was prepared by standard procedures. Effects of the ICL extract on the morphology of SCC-9 cells was visualized by microscopy. Cytotoxicity was determined by MTT assay. Effects of the ICL extract on colony forming ability of SCC-9 cells was evaluated using clonogenic assay. Cell cycle analysis was performed by flow cytometry and induction of apoptosis was determined by DNA fragmentation assay. The ICL extract treatment caused cytotoxicity and induced cell death in vitro in SCC-9 cells in a dose-dependent manner. This treatment also significantly reduced the clonogenic potential and inhibited cell proliferation by arresting the cell cycle in the G2/M phase. Furthermore, DNA fragmentation assays showed that the observed cell death was caused by apoptosis. This is the first report showing the anticancer activity of the methanol extracts from the leaves of I. cylindrica in human oral cancer cell line. Our data indicates that ICL extract could be considered as one of the lead compounds for the formulation of anticancer therapeutic agents to treat/manage human oral cancers. The natural abundance of I. cylindrica and its wide geographic distribution could render it one of the primary resource materials for preparation of anticancer therapeutic agents.
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Evaluation of medicinal plant hepatotoxicity in co-cultures of hepatocytes and monocytes.
Saad, Bashar; Dakwar, Suha; Said, Omar; Abu-Hijleh, Ghassan; Al Battah, Feras; Kmeel, Abedelsalam; Aziazeh, Hassan
2006-03-01
Non-parenchymal cells might play an important role in the modulation of xenobiotic metabolism in liver and its pharmacological and toxicological consequences. Therefore, the role of cell-to-cell interactions in herbal induced liver toxicity was investigated in monocultures of cells from the human hepatocyte cell line (HepG2) and in co-cultures of cells from the HepG2 cell line and cells from the human monocyte cell line (THP1). Cells were treated with various concentrations (1-500 microg ml(-1)) of extracts of Pistacia palaestina, Juglans regia and Quercus ithaburensis for 24 h. Extracts from Cleome droserifolia, a known toxic plant, were taken as positive control. In the co-culture system, toxic effects were observed after exposure to extracts of Pistacia palestina and C. droserifolia. These two extracts significantly reduced by cell viability as measured the MTT test and the LDH assay. Whereas in hepatocyte cultures, only extracts of C. droserifolia were found to affect the cell viability. The production levels of albumin from hepatocytes were not affected by treatment with plant extracts in both culture systems. It seems that the observed reduction in cell viability after exposure to extracts of P. palestina in co-cultures but not in monocultures is a result of monocyte-derived factors. The use of liver cell co-cultures is therefore a useful approach to investigate the influence of intercellular communication on xenobiotic metabolism in liver.
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Ye, Danyan; Jiang, Zebin; Zheng, Fuchun; Wang, Hongmei; Zhang, Yanmei; Gao, Fenfei; Chen, Peihong; Chen, Yicun; Shi, Ganggang
2015-09-16
Polysaccharides from Grateloupia livida (Harv.) Yamada (GL) were extracted by a heating circumfluence method. Single-factor experiments were performed for the three parameters: extraction time (X₁), extraction temperature (X₂) and the ratio of water to raw material (X₃) and their test range. From preliminary experimental results, one type of the response surface methodology, the Box-Behnken design was applied for the optimizing polysaccharide extraction conditions. The experimental data obtained were fitted to a second-order polynomial equation. The optimal conditions were extraction time 5 h, extraction temperature 100 °C and ratio of water to raw material 70 mL/g. Under these conditions, the experimental yield was 39.22% ± 0.09%, which well matched the predicted value (39.25%), with 0.9774 coefficient of determination (R²). GL polysaccharides had scavenging activities for DPPH and hydroxyl radicals in vitro. The scavenging rates for both radicals peaked at 20 mg/mL GL concentration. However, the positive standard, VC (ascorbic acid), possessed stronger antioxidant activities than GL polysaccharides. Furthermore, the anticancer activity of GL polysaccharides on HepG2 cell proliferation increased dose- and time-dependently, but the positive standard, 5-fluorouracil (5-fu) showed more significant anticancer activity in this study. Overall, GL polysaccharides may have potential applications in the medical and food industries.
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Anuar, Nordiyanah; Mohd Adnan, Ahmad Faris; Saat, Naziz; Aziz, Norkasmani; Mat Taha, Rosna
2013-01-01
Anthocyanins not just have various benefits in food industry but also have been used as natural colourants in cosmetic, coating products and as potential natural photosensitizers in solar cell. Thus, the main purpose of this study was to obtain information on the maximum yield of anthocyanin that can be recovered from Melastoma malabathricum fruit. Factors such as extraction temperature, extraction time, and solid to liquid ratio were identified to be significantly affecting anthocyanin extraction efficiency. By using three-level three-factor Box-Behnken design, the optimized conditions for anthocyanin extraction by acidified methanol (R (2) = 0.972) were temperature of 60°C, time of 86.82 min, and 0.5 : 35 (g/mL) solid to liquid ratio while the optimum extraction conditions by acidified ethanol (R (2) = 0.954) were temperature of 60°C, time of 120 min, and 0.5 : 23.06 (g/mL) solid to liquid ratio. The crude anthocyanin extract was further purified by using Amberlite XAD-7 and Sephadex LH-20 column chromatography. Identification of anthocyanins revealed the presence of cyanidin dihexoside, cyanidin hexoside, and delphinidin hexoside as the main anthocyanins in M. malabathricum fruit.
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Ren, Xuezhi; Guo, Xingzhi; Chen, Li; Guo, Minxia; Peng, Ning; Li, Rui
2014-08-01
Excessive activation of the microglia in the brain is involved in the development of several neurodegenerative diseases. Previous studies have indicated that (-)-epigallocatechin gallate (EGCG), a major active constituent of green tea, exhibits potent suppressive effects on the activation of microglia. As the 67 kDa laminin receptor (67LR) is a key element in cellular activation and migration, we investigated the effect of EGCG on cell migration and 67LR in lipopolysaccharide (LPS)-activated macrophagic RAW264.7 cells. The presence of EGCG (1-25 μM) markedly attenuated LPS-induced cell migration in a dose-dependent manner. However, the total amount of 67LR protein in the RAW264.7 cells was unaffected by EGCG, as revealed by Western blot analysis. In addition, confocal immunofluorescence microscopy indicated that EGCG caused a marked membrane translocation of 67LR from the membrane surface towards the cytoplasm. Cell-surface biotinylation analysis confirmed that EGCG induced a significant internalization of 67LR by 24-68% in a dose-dependent manner. This study helps to explain the pharmacological action of EGCG on 67LR, suggesting its potential use in the treatment of diseases associated with macrophage/microglia activation, such as neurodegenerative diseases and cancer.
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Lin, Yue; Yang, Linlin; Yue, Guiyin; Chen, Lifen; Qiu, Bin; Guo, Longhua; Lin, Zhenyu; Chen, Guonan
2016-10-01
Telomerase is one of the most common markers of human malignant tumors, such as uterine, stomach, esophageal, breast, colorectal, laryngeal squamous cell, thyroid, bladder, and so on. It is necessary to develop some sensitive but convenient detection methods for telomerase activity determination. In this study, a label-free and ultrasensitive electrochemiluminescence (ECL) biosensor has been fabricated to detect the activity of telomerase extracted from HeLa cells. Thiolated telomerase substrate (TS) primer was immobilized on the gold electrode surface through gold-sulfur (Au-S) interaction and then elongated by telomerase specifically. Then, it was hybridized with complementary DNA to form double-stranded DNA (dsDNA) fragments on the electrode surface, and Ru(phen)3 (2+) has been intercalated into the dsDNA grooves to act as the ECL probe. The enhanced ECL intensity has a linear relationship with the number of HeLa cells in the range of 5∼5000 and with a detection limit of 2 HeLa cells. The proposed ECL biosensor has high specificity to telomerase in the presence of common interferents. The relative standard deviations (RSDs) were <5 % at 100 HeLa cells. The proposed method provides a convenient approach for telomerase-related cancer screening or diagnosis.
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Tulsawani, Rajkumar; Gupta, Rashmi; Misra, Kshipra
2013-01-01
To investigate the protective efficacy of aqueous extract of Hippophae rhamnoides against chronic hypoxic injury using primary rat hepatocytes. The extract was prepared using maceration method and characterized by its phenolic and flavonoid content and chemical antioxidant capacity using ferric reducing antioxidant power assay. Hepatocytes were maintained in hypoxia chamber (3% and 1% oxygen) for 72 h. The cells kept under normoxic condition served as control. The cells were treated with the extract and flavonoids; isorhamentin, kaempferol or qurecetin-3-galactoside. After the end of exposure period; cell survival, reactive oxygen species (ROS), leakage of lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST), reduced glutathione (GSH), glutathione peroxidase (GPx), and superoxide dismutase (SOD) levels were measured. The extract showed presence of high phenolic and flavonoid content with significant antioxidant activity in chemical assay. The cell exposed to hypoxia showed concentration dependent cell death and harbored higher reactive oxygen species. In addition, these cells showed significant leakage of intracellular LDH, ALT, and AST accompanied by the diminished levels/activities of GSH, GPx, and SOD. The treatment of cells with aqueous extract of H. rhamnoides reduced hypoxia-induced cell death and prevented increase in ROS levels and leakage of intracellular LDH, ALT, and AST from cells. Moreover, these cells maintained better levels/activities of GSH, GPx, and SOD in comparison to the respective controls. The major flavonoids present in aqueous extract of H. rhamnoides; quercetin-3-galactoside, kaempferol, and isorhamentin also prevented hypoxia induced cell injury individually or in combination, however, the protection offered by these compounds taken together could not match to that of the extract. Overall the findings reveal significance of aqueous extract of H. rhamnoides in controlling ROS-meditated hypoxic injury in cells and can be useful in many hepatic complications.
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NASA Astrophysics Data System (ADS)
Sánchez-Guerrero, Guillermo E.; Viera-González, Perla M.; Ceballos-Herrera, Daniel E.; Martínez-Guerra, Edgar
2016-09-01
Extraction light in light-pipes with different specular surfaces was analyzed. In the analysis, the impact of the surface shape in all properties of the extracted light in order to obtain an efficient extraction and a uniform illumination using a LED as light source. Also, several parameters of the specular surface to obtain spatial uniformity inside the light-pipe are considered. In this case, the simulation was made for a rectangular lightpipe. One objective of this work is to compare how the front face shape of the specular surface can affect the extraction of light in the lateral face of the light-pipe, only straight and elliptical front faces were used in this work and the comparison between them at different tilts and lengths were made. The main purpose of the front face was extract the light uniformly at the lateral face and this was done by studying simulations on OpticStudio Zemax. The results show how the extraction length is lower in the elliptical front but its total power performs better than the line front.
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Impact of cranberry on Escherichia coli cellular surface characteristics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, Brandy J.; Lin Baochuan; Dinderman, Michael A.
2008-12-19
The anti-adhesive effects of cranberry have been attributed to both interactions of its components with the surface of bacterial cells and to inhibition of p-fimbriae expression. Previous reports also suggested that the presence of cranberry juice changed the Gram stain characteristics of Escherichia coli. Here, we show that the morphology of E. coli is changed when grown in the presence of juice or extract from Vaccinium macrocarpon (cranberry). Gene expression analysis indicates the down regulation of flagellar basal body rod and motor proteins. Consistent with this finding and previous reports, the SEM images indicate a decrease in the visible p-fimbriae.more » The iodine used in Gram-staining protocols was found to interact differently with the bacterial membrane when cells were cultured in spiked media. Slight alterations in the Gram stain protocol demonstrated that culturing in the presence of cranberry juice does not change the Gram stain characteristics contradicting other reports.« less
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Method for estimating protein binding capacity of polymeric systems.
Sharma, Vaibhav; Blackwood, Keith A; Haddow, David; Hook, Lilian; Mason, Chris; Dye, Julian F; García-Gareta, Elena
2015-01-01
Composite biomaterials made from synthetic and protein-based polymers are extensively researched in tissue engineering. To successfully fabricate a protein-polymer composite, it is critical to understand how strongly the protein binds to the synthetic polymer, which occurs through protein adsorption. Currently, there is no cost-effective and simple method for characterizing this interfacial binding. To characterize this interfacial binding, we introduce a simple three-step method that involves: 1) synthetic polymer surface characterisation, 2) a quick, inexpensive and robust novel immuno-based assay that uses protein extraction compounds to characterize protein binding strength followed by 3) an in vitro 2D model of cell culture to confirm the results of the immuno-based assay. Fibrinogen, precursor of fibrin, was adsorbed (test protein) on three different polymeric surfaces: silicone, poly(acrylic acid)-coated silicone and poly(allylamine)-coated silicone. Polystyrene surface was used as a reference. Characterisation of the different surfaces revealed different chemistry and roughness. The novel immuno-based assay showed significantly stronger binding of fibrinogen to both poly(acrylic acid) and poly(allylamine) coated silicone. Finally, cell studies showed that the strength of the interaction between the protein and the polymer had an effect on cell growth. This novel immuno-based assay is a valuable tool in developing composite biomaterials of synthetic and protein-based polymers with the potential to be applied in other fields of research where protein adsorption onto surfaces plays an important role.
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Microchip-based cell lysis and DNA extraction from sperm cells for application to forensic analysis.
Bienvenue, Joan M; Duncalf, Natalie; Marchiarullo, Daniel; Ferrance, Jerome P; Landers, James P
2006-03-01
The current backlog of casework is among the most significant challenges facing crime laboratories at this time. While the development of next-generation microchip-based technology for expedited forensic casework analysis offers one solution to this problem, this will require the adaptation of manual, large-volume, benchtop chemistry to small volume microfluidic devices. Analysis of evidentiary materials from rape kits where semen or sperm cells are commonly found represents a unique set of challenges for on-chip cell lysis and DNA extraction that must be addressed for successful application. The work presented here details the development of a microdevice capable of DNA extraction directly from sperm cells for application to the analysis of sexual assault evidence. A variety of chemical lysing agents are assessed for inclusion in the extraction protocol and a method for DNA purification from sperm cells is described. Suitability of the extracted DNA for short tandem repeat (STR) analysis is assessed and genetic profiles shown. Finally, on-chip cell lysis methods are evaluated, with results from fluorescence visualization of cell rupture and DNA extraction from an integrated cell lysis and purification with subsequent STR amplification presented. A method for on-chip cell lysis and DNA purification is described, with considerations toward inclusion in an integrated microdevice capable of both differential cell sorting and DNA extraction. The results of this work demonstrate the feasibility of incorporating microchip-based cell lysis and DNA extraction into forensic casework analysis.
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Gürbüzer, Bahadir; Pikdöken, Levent; Tunali, Mustafa; Urhan, Muammer; Küçükodaci, Zafer; Ercan, Feriha
2010-05-01
To evaluate the effect of platelet-rich fibrin (PRF) on the early bone healing process with bone scintigraphy based on technetium-99m methylene diphosphonate uptake in third molar extraction sockets. Fourteen patients with bilaterally soft tissue impacted third mandibular molars were included in the study. The right and left impacted third molars were surgically extracted in the same session. PRF was randomly administered into one of the extraction sockets, whereas the contralateral sockets were left without treatment. Four weeks after surgery, scintigrams were obtained to evaluate scintigraphic differences between PRF-treated and non-PRF-treated sockets. After completion of the clinical study, PRF samples were evaluated by light and scanning electron microscopy. The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 4 weeks postoperatively (P > .05). Abundant fibrin and inflammatory cells were observed by light microscopic examination of PRF samples. Scanning electron microscopic analysis of PRF revealed the existence of platelet aggregates in a fibrin network and crystalline particles on the outer surface of PRF. PRF might not lead to enhanced bone healing in soft tissue impacted mandibular third molar extraction sockets 4 weeks after surgery. PRF exhibits the potential characteristics of an autologous fibrin matrix. However, whether the presence of crystal-like particles on the outer surface of PRF alters bone healing should be investigated further. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
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Factors affecting skin tannin extractability in ripening grapes.
Bindon, Keren A; Madani, S Hadi; Pendleton, Phillip; Smith, Paul A; Kennedy, James A
2014-02-05
The acetone-extractable (70% v/v) skin tannin content of Vitis vinifera L. cv. Cabernet Sauvignon grapes was found to increase during late-stage ripening. Conversely, skin tannin content determined following ethanol extraction (10, 20, and 50% v/v) did not consistently reflect this trend. The results indicated that a fraction of tannin became less extractable in aqueous ethanol during ripening. Skin cell walls were observed to become more porous during ripening, which may facilitate the sequestering of tannin as an adsorbed fraction within cell walls. For ethanol extracts, tannin molecular mass increased with advancing ripeness, even when extractable tannin content was constant, but this effect was negligible in acetone extracts. Reconstitution experiments with isolated skin tannin and cell wall material indicated that the selectivity of tannin adsorption by cell walls changed as tannin concentration increased. Tannin concentration, tannin molecular mass, and cell wall porosity are discussed as factors that may influence skin tannin extractability.
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Luo, Lihua; Gong, Wenrong; Zhou, Yi; Yang, Lin; Li, Daokun; Huselstein, Celine; Wang, Xiong; He, Xiaohua; Li, Yinping; Chen, Yun
2015-01-01
To evaluate the in vitro cytocompatibility of cellulose/soy protein isolate composite membranes (CSM) with Schwann cells and in vivo toxicity to animals. A series of cellulose/soy protein isolate composite membranes (CSM) were prepared by blending, solution casting and coagulation process. The cytocompatibility of the CSM to Schwann cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and by direct cells culture of Schwann cells on the surfaces of the CSM, respectively. The in vivo toxicity of the CSM to animals were also evaluated by acute toxicity testing, skin sensitization testing, pyrogen testing and intracutaneous stimulation testing, respectively, according to the ISO 10993 standard. The MTT assay showed that the cell viability of Schwann cells cultured in extracts from the CSM was higher than that from the neat cellulose membrane without containing SPI component. The direct cells culture indicated that the Schwann cells could attach and grow well on the surface of the CSM and the incorporation of SPI into cellulose contributed to improvement of cell adhesion and proliferation. The evaluations of in vivo biological safety suggested that the CSM showed no acute toxicity, no skin sensitization and no intracutaneous stimulation to the experimental animals. The CSM had in vitro cytocompatibility with Schwann cells and biological safety to animals, suggesting potential for the applications as nerve conduit for the repair of nerve defect.
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Channel catfish response to ultraviolet-B radiation
Ewing, M.S.; Blazer, V.S.; Fabacher, D.L.; Little, E.E.; Kocan, K.M.
1999-01-01
Fingerling channel catfish Ictalurus punctatus exposed to simulated ultraviolet-B radiation at an average daily dose of 2.9 J/cm2 were quite sensitive to the radiation. After a 24-h exposure, thinning of the most dorsal epidermis frequently was accompanied by edema. Compared with epidermis of unexposed fish, mucous cells in exposed fish were less superficial and club cells were less numerous both dorsally and high on the lateral surface of the body. Sunburn cells with pyknotic nuclei were evident in the epidermis of exposed fish. Among fish exposed for 48 h, focal necrosis and sloughing of the outer epidermal layer were widespread. A methanol-extractable skin substance that is associated with resistance to sunburn in other fish species was not detected in channel catfish.
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Neutrophilic leukocyte membrane proteins. I. Isolation.
Hawkins, D; Sauvé, M
1978-03-01
Rabbit exudate-derived PMN were homogenized and the cell membranes isolated on a two-phase aqueous system. Glycoproteins were extracted from cell membranes with lithium diiodosalicylate. SDS polyacrylamide gel electrophoretic analysis showed a consistent pattern of three major glycoprotein entities. Cells radioiodinated supravitally showed most of the radioactivity associated with larger glycoprotein entities whereas PMN membranes radiolabeled after isolation yielded a single major peak of radioactivity associated with a much smaller protein entity. Heterologous antisera against rabbit PMN, PMN membranes, and membrane glycoproteins were all cytotoxic for PMN in the presence of complement, and all bound to the PMN surface as demonstrated with immunocolloidal gold on electron microscopy. The data suggest that one or more glycoprotein entities are membrane-associated ectoglycoproteins which can be radiolabeled supravitally.
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[Validation of Differential Extraction Kit in forensic sexual assault cases].
Wu, Dan; Cao, Yu; Xu, Yan; He, Bai-Fang; Bi, Gang; Zhou, Huai-Gu
2009-12-01
To evaluate the validity of Differential Extraction Kit in isolating spermatozoa and epithelial cell DNA from mixture samples. Selective lysis of spermatid and epithelial cells combined with paramagnetic particle method were applied to extract the DNA from the mock samples under controlled conditions and forensic case samples, and template DNA were analyzed by STR genotype method. This Differential Extraction Kit is efficient to obtain high quality spermatid and epithelial cell DNA from the mixture samples with different proportion of sperm to epithelial cell. The Differential Extraction Kit can be applied in DNA extraction for mixed stain from forensic sexual assault samples.
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Anand, K; Tiloke, C; Phulukdaree, A; Ranjan, B; Chuturgoon, A; Singh, S; Gengan, R M
2016-12-01
The biosynthesis of nanostructured biopalladium nanoparticles (PdNPs) from an aqueous solution of crystalline palladium acetate is reported. For the synthesised PdNPs in solution, an agroforest biomass waste petal of Moringa oleifera derived bis-phthalate was used as natural reducing and biocapping agents. Continuous absorption in the UV region and subsequent brown colour change confirmed the formation of PdNPs. A strong surface plasmon peak for PdNPs occurred at 460nm. PdNPs were characterized by SEM with EDX, FTIR, TEM and DLS. The chemical composition of the aqueous extract was determined by GC-MS coupled with FTIR and 1 NMR. The catalytic degradation effect by PdNPs on industrial organic toxic effluents p-nitrophenol (PNP) and methylene blue dye was monitored by UV Spectroscopy. On the other hand PdNPs catalysed the base mediated suzuki coupling reaction for biphenyl synthesis, in water. Moreover, PdNPs were found to be reusable catalysts. Toxicity studies of PdNPs showed that the death of brine shrimp to be <50%. Therefore, PdNPs displayed potential for further anticancer studies via tumour cell lines. The in vitro cytotoxicity evaluation of the extract capped nanoparticles was carried out using human lung carcinoma cells (A549) and peripheral lymphocytes normal cells by MTT cell viability assay. Also, PdNPs showed antibacterial activity against Enterococcus faecalis among the different tested strains, including Bacillus cereus, Staphylococcus aureus, Esherichia coli and Candida albicans, Candida utilis. Copyright © 2016 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Sarkar, Sonia; Kotteeswaran, Venkatesan
2018-06-01
Plants contain different important phytochemicals that can be used as a potential treatment for various ailments including cancer. The green synthesis of silver nanoparticles from the extract of different plant parts has gained a wide range of engrossment among the researchers due to its unique optical and structural property. The aim of this study is green synthesis of silver nanoparticles from the aqueous leaf extract of pomegranate (Punica granatum) and to investigate its anticancer activity on human cervical cancer cells (HeLa). The synthesis of silver nanoparticle was depicted by the colour change from golden yellowish to dark brownish, UV-visible spectral analysis gave a characteristic surface plasmon absorption peak at . Further morphological characterization was done by Zeta potential where the size analysis was depicted to be 46.1 nm and zeta potential as . Fourier transform infrared spectroscopy (FTIR) inferred 3 intense sharp peaks at , , , confirmed the presence of flavonoids and polyphenols. The scanning electron microscopy (SEM) analysis with energy diffraction spectroscopy (EDS) confirmed the presence of silver nanoparticles with size ranged from to . X-ray diffraction (XRD) confirmed the crystallographic nature of silver. The cell proliferation activity of nanoparticles was tested by 3, ‑4, 5 dimethylthiazol-2,5 diphenyl tetrazolium bromide (MTT) assay where the inhibitory concentration () was found at inhibiting of HeLa cell line. The anticancer activity of nanoparticles was determined by lactate dehydrogenase (LDH) assay where showed of cytotoxicity. Furthermore, the anticancer property of nanoparticles was confirmed by the DNA fragmentation assay.
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Moura, Daniel R; Silveira, Maria L; O'Connor, George A; Wise, William R
2011-09-01
Rapid infiltration basins (RIBs) are effective tools for wastewater treatment and groundwater recharge, but continuous application of wastewater can increase soil P concentrations and subsequently impact groundwater quality. The objectives of this study were to (1) investigate the effects of reclaimed water infiltration rate and "age" of RIBs on soil P concentrations at various depths, and (2) estimate the degree (percentage) of sorption equilibrium reached between effluent P and soil attained during reclaimed water application to different RIBs. The study was conducted in four contrasting cells of a RIB system with up to a 25 year history of secondary wastewater application. Soil samples were collected from 0 to 300 cm depth at 30 cm intervals and analyzed for water extractable phosphorus (WEP) and oxalate extractable P, Al, and Fe concentrations. Water extractable P and P saturation ratio (PSR) values were generally greater in the cells receiving reclaimed water compared to control soils, suggesting that reclaimed water P application can increase soil P concentrations and the risk of P movement to greater depths. Differences between treatment and control samples were more evident in cells with longer histories of reclaimed water application due to greater P loading. Data also indicated considerable spatial variability in WEP concentrations and PSR values, especially within cells from RIBs characterized by fast infiltration rates. This occurs because wastewater-P flows through surface soils much faster than the minimum time required for sorption equilibrium to occur. Studies should be conducted to investigate soil P saturation at deeper depths to assess possible groundwater contamination.
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Jiménez-Medina, Eva; Garcia-Lora, Angel; Paco, Laura; Algarra, Ignacio; Collado, Antonia; Garrido, Federico
2006-01-01
Background Phytopharmacological studies of different Calendula extracts have shown anti-inflamatory, anti-viral and anti-genotoxic properties of therapeutic interest. In this study, we evaluated the in vitro cytotoxic anti-tumor and immunomodulatory activities and in vivo anti-tumor effect of Laser Activated Calendula Extract (LACE), a novel extract of the plant Calendula Officinalis (Asteraceae). Methods An aqueous extract of Calendula Officinalis was obtained by a novel extraction method in order to measure its anti-tumor and immunomodulatory activities in vitro. Tumor cell lines derived from leukemias, melanomas, fibrosarcomas and cancers of breast, prostate, cervix, lung, pancreas and colorectal were used and tumor cell proliferation in vitro was measured by BrdU incorporation and viable cell count. Effect of LACE on human peripheral blood lymphocyte (PBL) proliferation in vitro was also analyzed. Studies of cell cycle and apoptosis were performed in LACE-treated cells. In vivo anti-tumor activity was evaluated in nude mice bearing subcutaneously human Ando-2 melanoma cells. Results The LACE extract showed a potent in vitro inhibition of tumor cell proliferation when tested on a wide variety of human and murine tumor cell lines. The inhibition ranged from 70 to 100%. Mechanisms of inhibition were identified as cell cycle arrest in G0/G1 phase and Caspase-3-induced apoptosis. Interestingly, the same extract showed an opposite effect when tested on PBLs and NKL cell line, in which in vitro induction of proliferation and activation of these cells was observed. The intraperitoneal injection or oral administration of LACE extract in nude mice inhibits in vivo tumor growth of Ando-2 melanoma cells and prolongs the survival day of the mice. Conclusion These results indicate that LACE aqueous extract has two complementary activities in vitro with potential anti-tumor therapeutic effect: cytotoxic tumor cell activity and lymphocyte activation. The LACE extract presented in vivo anti-tumoral activity in nude mice against tumor growth of Ando-2 melanoma cells. PMID:16677386
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Huyan, Ting; Li, Qi; Wang, Yi-Lin; Li, Jing; Zhang, Jian-Yang; Liu, Ya-Xiong; Shahid, Muhammad Riaz; Yang, Hui; Li, Huan-Qing
2016-06-05
Sonchus oleraceus (L.) L (SO) and Juniperus sabina L (JS) are traditional medicinal plants in China. And the aqueous extracts of them have been used to treat tumor, inflammatory diseases, infection and so on in Chinese folk culture. However, the underlying mechanisms of their anti-tumor activities have not been illustrated yet. This study aims to evaluate the inhibitory effects of aqueous extracts from SO and JS on tumor cells. The prepared aqueous extracts of SO and JS were used to treat HepG-2 and K562 tumor cells, while the human peripheral blood mononuclear cells (PBMCs) were set as normal control. The viabilities, cell cycle and apoptosis of tumor cells after extracts treatment were assessed, in addition the expression of apoptosis-related genes (FasL, caspase 3, 6, 7, 8, 9, and 10) were analyzed. Meanwhile, the adherence and migration of HepG-2 were tested, and the expression levels of MMPs and ICAM-1 were analyzed. On top of that, the pSTAT in the two cells were also analyzed and suggested the related signaling pathway that the extracts acted on with in these tumor cells. Results showed that aqueous extracts of SO and JS have inhibitory effects on HepG-2 and K562 cells by decreasing cell viability and inducing apoptosis via up-regulation of the expression of the apoptosis-related genes FasL, caspase 3 and caspase 9. The extracts had different IC50 on tumor cells and PBMCs, which could block the tumor cell cycle at the G(0)/G(1) stage and significantly inhibit the adherence of HepG-2 cells. The extracts inhibited migration of these cells by inhibiting the expression of ICAM-1, MMP-2 and MMP-9. Further study indicated that the inhibition of pSTAT1 and 3 might be responsible for the inhibitory effects of the extracts on tumor cells. The results of this study indicated that SO and JS extracts had the anti-tumor effects, which may be developed as novel anti-tumor drugs and used in cancer therapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
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Withania somnifera Root Extract Has Potent Cytotoxic Effect against Human Malignant Melanoma Cells
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
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Toxicity of extracts from disposable chopsticks, toothpicks, and paper cups on L-929 cells.
Li, Juntao; Chen, Sifan; Li, Wenxue; Yang, Guangyu; Zhu, Wei
2015-04-01
To evaluate the toxicity of extracts from disposable chopsticks, toothpicks, and paper cups on L-929 cells. We followed national standards to prepare the extracts from disposable chopsticks, toothpicks, and paper cups used for the cell culture media, and the morphology of L-929 cells was observed with an optical microscope. The loss rate for adherent cells was evaluated with the trypan blue exclusion method, and cell proliferation was determined using the WST-1 assay. Compared with the control group, the cells cultured in media containing the extracts showed signs of apoptosis and necrosis after culturing for 4 or 7 days, and the loss rate for adherent cells was significantly increased (P < 0.05). An obvious decrease in cell viability was also observed (P < 0.05). The extracts from disposable chopsticks, toothpicks, and paper cups can affect the growth and proliferation of L-929 cells and are potentially toxic to humans.
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Cinnamon extract suppresses experimental colitis through modulation of antigen-presenting cells.
Kwon, Ho-Keun; Hwang, Ji-Sun; Lee, Choong-Gu; So, Jae-Seon; Sahoo, Anupama; Im, Chang-Rok; Jeon, Won Kyung; Ko, Byoung Seob; Lee, Sung Haeng; Park, Zee Yong; Im, Sin-Hyeog
2011-02-28
To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells. Cinnamon extract was used to treat murine macrophage cell line (Raw 264.7), mouse primary antigen-presenting cells (APCs, MHCII(+)) and CD11c(+) dendritic cells to analyze the effects of cinnamon extract on APC function. The mechanisms of action of cinnamon extract on APCs were investigated by analyzing cytokine production, and expression of MHC antigens and co-stimulatory molecules by quantitative real-time PCR and flow cytometry. In addition, the effect of cinnamon extract on antigen presentation capacity and APC-dependent T-cell differentiation were analyzed by [H(3)]-thymidine incorporation and cytokine analysis, respectively. To confirm the anti-inflammatory effects of cinnamon extract in vivo, cinnamon or PBS was orally administered to mice for 20 d followed by induction of experimental colitis with 2,4,6 trinitrobenzenesulfonic acid. The protective effects of cinnamon extract against experimental colitis were measured by checking clinical symptoms, histological analysis and cytokine expression profiles in inflamed tissue. Treatment with cinnamon extract inhibited maturation of MHCII(+) APCs or CD11c(+) dendritic cells (DCs) by suppressing expression of co-stimulatory molecules (B7.1, B7.2, ICOS-L), MHCII and cyclooxygenase (COX)-2. Cinnamon extract induced regulatory DCs (rDCs) that produce low levels of pro-inflammatory cytokines [interleukin (IL)-1β, IL-6, IL-12, interferon (IFN)-γ and tumor necrosis factor (TNF)-α] while expressing high levels of immunoregulatory cytokines (IL-10 and transforming growth factor-β). In addition, rDCs generated by cinnamon extract inhibited APC-dependent T-cell proliferation, and converted CD4(+) T cells into IL-10(high) CD4(+) T cells. Furthermore, oral administration of cinnamon extract inhibited development and progression of intestinal colitis by inhibiting expression of COX-2 and pro-inflammatory cytokines (IL-1β, IFN-γ and TNF-α), while enhancing IL-10 levels. Our study suggests the potential of cinnamon extract as an anti-inflammatory agent by targeting the generation of regulatory APCs and IL-10(+) regulatory T cells.
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Hypoxia affects cellular responses to plant extracts.
Liew, Sien-Yei; Stanbridge, Eric J; Yusoff, Khatijah; Shafee, Norazizah
2012-11-21
Microenvironmental conditions contribute towards varying cellular responses to plant extract treatments. Hypoxic cancer cells are known to be resistant to radio- and chemo-therapy. New therapeutic strategies specifically targeting these cells are needed. Plant extracts used in Traditional Chinese Medicine (TCM) can offer promising candidates. Despite their widespread usage, information on their effects in hypoxic conditions is still lacking. In this study, we examined the cytotoxicity of a series of known TCM plant extracts under normoxic versus hypoxic conditions. Pereskia grandifolia, Orthosiphon aristatus, Melastoma malabathricum, Carica papaya, Strobilanthes crispus, Gynura procumbens, Hydrocotyle sibthorpioides, Pereskia bleo and Clinacanthus nutans leaves were dried, blended into powder form, extracted in methanol and evaporated to produce crude extracts. Human Saos-2 osteosarcoma cells were treated with various concentrations of the plant extracts under normoxia or hypoxia (0.5% oxygen). 24h after treatment, an MTT assay was performed and the IC(50) values were calculated. Effect of the extracts on hypoxia inducible factor (HIF) activity was evaluated using a hypoxia-driven firefly luciferase reporter assay. The relative cytotoxicity of each plant extract on Saos-2 cells was different in hypoxic versus normoxic conditions. Hypoxia increased the IC(50) values for Pereskia grandifola and Orthosiphon aristatus extracts, but decreased the IC(50) values for Melastoma malabathricum and Carica papaya extracts. Extracts of Strobilanthes crispus, Gynura procumbens, Hydrocotyle sibthorpioides had equivalent cytotoxic effects under both conditions. Pereskia bleo and Clinacanthus nutans extracts were not toxic to cells within the concentration ranges tested. The most interesting result was noted for the Carica papaya extract, where its IC(50) in hypoxia was reduced by 3-fold when compared to the normoxic condition. This reduction was found to be associated with HIF inhibition. Hypoxia variably alters the cytotoxic effects of TCM plant extracts on cancer cells. Carica papaya showed enhanced cytotoxic effect on hypoxic cancer cells by inhibiting HIF activities. These findings provide a plausible approach to killing hypoxic cancer cells in solid tumors. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
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Farshori, Nida Nayyar; Al-Sheddi, Ebtsam S; Al-Oqail, Mai M; Hassan, Wafaa H B; Al-Khedhairy, Abdulaziz A; Musarrat, Javed; Siddiqui, Maqsood A
2015-08-01
The present investigations were carried out to study the protective potential of four extracts (namely petroleum ether extract (LCR), chloroform extract (LCM), ethyl acetate extract (LCE), and alcoholic extract (LCL)) of Lavandula coronopifolia on oxidative stress-mediated cell death induced by ethanol, a known hepatotoxin in human hapatocellular carcinoma (HepG2) cells. Cells were pretreated with LCR, LCM, LCE, and LCL extracts (10-50 μg/ml) of L. coronopifolia for 24 h and then ethanol was added and incubated further for 24 h. After the exposure, cell viability using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and neutral red uptake assays and morphological changes in HepG2 cells were studied. Pretreatment with various extracts of L. coronpifolia was found to be significantly effective in countering the cytotoxic responses of ethanol. Antioxidant properties of these L. coronopifolia extracts against reactive oxygen species (ROS) generation, lipid peroxidation (LPO), and glutathione (GSH) levels induced by ethanol were investigated. Results show that pretreatment with these extracts for 24 h significantly inhibited ROS generation and LPO induced and increased the GSH levels reduced by ethanol. The data from the study suggests that LCR, LCM, LCE, and LCL extracts of L. coronopifolia showed hepatoprotective activity against ethanol-induced damage in HepG2 cells. However, a comparative study revealed that the LCE extract was found to be the most effective and LCL the least effective. The hepatoprotective effects observed in the study could be associated with the antioxidant properties of these extracts of L. coronopifolia. © The Author(s) 2013.
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NASA Astrophysics Data System (ADS)
Ramar, Manikandan; Manikandan, Beulaja; Marimuthu, Prabhu Narayanan; Raman, Thiagarajan; Mahalingam, Anjugam; Subramanian, Palanisamy; Karthick, Saravanan; Munusamy, Arumugam
2015-04-01
In the present study, we have synthesized silver nanoparticles by a simple and eco-friendly method using unripe fruits of Solanum trilobatum. The aqueous silver ions when exposed to unripe fruits extract were reduced and stabilized over long time resulting in biosynthesis of surface functionalized silver nanoparticles. The bio-reduced silver nanoparticles were characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX) and X-ray diffraction (XRD). These biologically synthesized silver nanoparticles were tested for its antibacterial activity against few human pathogenic bacteria including Gram-positive (Streptococcus mutans, Enterococcus faecalis) and Gram-negative (Escherichia coli, Klebsiella pneumoniae) bacteria. In addition, we also demonstrated anticancer activity of these nanoparticles in vitro against human breast cancer cell line (MCF 7) using MTT, nuclear morphology assay, Western blot and RT-PCR expression. These results taken together show the potential applications of biosynthesized silver nanoparticles using S. trilobatum fruits.
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Slow cooling and highly efficient extraction of hot carriers in colloidal perovskite nanocrystals.
Li, Mingjie; Bhaumik, Saikat; Goh, Teck Wee; Kumar, Muduli Subas; Yantara, Natalia; Grätzel, Michael; Mhaisalkar, Subodh; Mathews, Nripan; Sum, Tze Chien
2017-02-08
Hot-carrier solar cells can overcome the Schottky-Queisser limit by harvesting excess energy from hot carriers. Inorganic semiconductor nanocrystals are considered prime candidates. However, hot-carrier harvesting is compromised by competitive relaxation pathways (for example, intraband Auger process and defects) that overwhelm their phonon bottlenecks. Here we show colloidal halide perovskite nanocrystals transcend these limitations and exhibit around two orders slower hot-carrier cooling times and around four times larger hot-carrier temperatures than their bulk-film counterparts. Under low pump excitation, hot-carrier cooling mediated by a phonon bottleneck is surprisingly slower in smaller nanocrystals (contrasting with conventional nanocrystals). At high pump fluence, Auger heating dominates hot-carrier cooling, which is slower in larger nanocrystals (hitherto unobserved in conventional nanocrystals). Importantly, we demonstrate efficient room temperature hot-electrons extraction (up to ∼83%) by an energy-selective electron acceptor layer within 1 ps from surface-treated perovskite NCs thin films. These insights enable fresh approaches for extremely thin absorber and concentrator-type hot-carrier solar cells.
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NASA Astrophysics Data System (ADS)
Roshila, M. L.; Hashim, U.; Azizah, N.; Nadzirah, Sh.; Arshad, M. K. Md; Ruslinda, A. R.; Gopinath, Subash C. B.
2017-03-01
This paper principally delineates to the detection process of Human Papillomavirus (HPV) DNA test. HPV is an extremely common virus infection that infected to human by the progressions cell in the cervix cell. The types of HPV that give a most exceedingly awful infected with cervical cancer is 16 and 18 other than 31 and 45. The HPV DNA probe is immobilized with a different concentration to stabilize the sensitivity. A technique of rapid and sensitive for the HPV identification was proposed by coordinating basic DNA extraction with a quality of DNA. The extraction of the quality of DNA will make a proficiency of the discovery procedure. It will rely on the sequence of the capture probes and the way to support their attached. The fabrication, surface modification, immobilization and hybridization procedures are described by current-voltage (I-V) estimation by utilizing KEITHLEY 6487. This procedure will play out a decent affectability and selectivity of HPV discovery.
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A Chronic Autoimmune Dry Eye Rat Model with Increase in Effector Memory T Cells in Eyeball Tissue.
Hou, Aihua; Bose, Tanima; Chandy, K George; Tong, Louis
2017-06-07
Dry eye disease is a very common condition that causes morbidity and healthcare burden and decreases the quality of life. There is a need for a suitable dry eye animal model to test novel therapeutics to treat autoimmune dry eye conditions. This protocol describes a chronic autoimmune dry eye rat model. Lewis rats were immunized with an emulsion containing lacrimal gland extract, ovalbumin, and complete Freund's adjuvant. A second immunization with the same antigens in incomplete Freund's adjuvant was administered two weeks later. These immunizations were administered subcutaneously at the base of the tail. To boost the immune response at the ocular surface and lacrimal glands, lacrimal gland extract and ovalbumin were injected into the forniceal subconjunctiva and lacrimal glands 6 weeks after the first immunization. The rats developed dry eye features, including reduced tear production, decreased tear stability, and increased corneal damage. Immune profiling by flow cytometry showed a preponderance of CD3 + effector memory T cells in the eyeball.
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A Chronic Autoimmune Dry Eye Rat Model with Increase in Effector Memory T Cells in Eyeball Tissue
Hou, Aihua; Bose, Tanima; Chandy, K. George; Tong, Louis
2017-01-01
Dry eye disease is a very common condition that causes morbidity and healthcare burden and decreases the quality of life. There is a need for a suitable dry eye animal model to test novel therapeutics to treat autoimmune dry eye conditions. This protocol describes a chronic autoimmune dry eye rat model. Lewis rats were immunized with an emulsion containing lacrimal gland extract, ovalbumin, and complete Freund's adjuvant. A second immunization with the same antigens in incomplete Freund's adjuvant was administered two weeks later. These immunizations were administered subcutaneously at the base of the tail. To boost the immune response at the ocular surface and lacrimal glands, lacrimal gland extract and ovalbumin were injected into the forniceal subconjunctiva and lacrimal glands 6 weeks after the first immunization. The rats developed dry eye features, including reduced tear production, decreased tear stability, and increased corneal damage. Immune profiling by flow cytometry showed a preponderance of CD3+ effector memory T cells in the eyeball. PMID:28654074
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Cunci, Lisandro; Vargas, Marina Martinez; Cunci, Roman; Gomez-Moreno, Ramon; Perez, Ivan; Baerga-Ortiz, Abel; Gonzalez, Carlos I; Cabrera, Carlos R
2014-10-15
The enzyme telomerase is present in about 85% of human cancers which makes it not only a good target for cancer treatment but also an excellent marker for cancer detection. Using a single stranded DNA probe specific for telomerase binding and reverse transcription tethered to an interdigital gold electrode array surface, the chromosome protection provided by the telomerase was replicated and followed by Electrochemical Impedance Spectroscopy as an unlabeled biosensor. Using this system designed in-house, easy and affordable, impedance measurements were taken while incubating at 37 °C and promoting the probe elongation. This resulted in up to 14-fold increase in the charge transfer resistance when testing a telomerase-positive nuclear extract from Jurkat cells compared to the heat-inactivated telomerase-negative nuclear extract. The electron transfer process at the Au electrodes was studied before the elongation, at different times after the elongation, and after desorption of non-specific binding.
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Cytotoxicity and antiviral activity of methanol extract from Polygonum minus
NASA Astrophysics Data System (ADS)
Wahab, Noor Zarina Abd; Bunawan, Hamidun; Ibrahim, Nazlina
2015-09-01
A study was carried out to test the cytotoxicity and antiviral effects of methanolic extracts from the leaves and stem of Polygonum minus or kesum. Cytotoxicity tests were performed on Vero cells indicates the LC50 value for leaf extract towards the Vero cells was 875 mg/L and the LC50 value for stem extract was 95 mg/L. The LC50 values indidcate the non-cytotoxic effect of the extracts and worth for further testing. Antiviral test were carried out towards herpes simplex virus infected Vero cells using three concentration of extract which were equivalent to 1.0 LC50, 0.1 LC50 and 0.01 LC50. Three different treatments to detect antiviral activity were used. Mild antiviral activity of the stem extract was detected when cells were treated for 24 hours with plant extract before viral infection. This demonstrates the capability of the test compound to protect the cells from viral attachment and of the possible prophylactic effect of the P. minus stem methanol extract.
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Alguacil, L F; Galán de Mera, A; Gómez, J; Llinares, F; Morales, L; Muñoz-Mingarro, M D; Pozuelo, J M; Vicente Orellana, J A
2000-06-01
Aqueous and alcoholic extracts of pods and flowers of Tecoma sambucifolia H.B.K. (Bignoniaceae) ('huarumo') were analysed to determine their anti-inflammatory activity (carrageenan-induced edema test), antinociceptive activity (acetic acid writhing test) and 'in vitro' toxicity in Chinese hamster ovary cells, human hepatome cells and human larynx epidermal carcinoma cells. The cytotoxic effects of both extracts were evaluated by two endpoint systems: neutral red uptake assay and tetrazolium assay. The results showed that all extracts have anti-inflammatory and antinociceptive activity, but the highest potency is that of the alcoholic extracts. There were significant differences in cytotoxicity between extracts and among the response of cells to them. The highest cytotoxicity was noted with the alcoholic extract, and the human hepatome cell line was the most sensitive, especially to the alcoholic extract of flowers. The aqueous pod extract appeared to have the best pharmaco-toxicological profile, since it provided a significant reduction of both pain and inflammation together with the lowest cytotoxicity.
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No, Jin-Gu; Choi, Mi-Kyung; Kwon, Dae-Jin; Yoo, Jae Gyu; Yang, Byoung-Chul; Park, Jin-Ki; Kim, Dong-Hoon
2015-01-01
Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The Chariot(TM) reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3 lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear skin fibroblasts and cloned embryos.
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Yadav, Mukesh Kumar; Choi, June; Song, Jae-Jun
2014-03-01
Gentamicin (GM) is a commonly used aminoglycoside antibiotic that generates free oxygen radicals within the inner ear, which can cause vestibulo-cochlear toxicity and permanent damage to the sensory hair cells and neurons. Piper longum L. (PL) is a well-known spice and traditional medicine in Asia and Pacific islands, which has been reported to exhibit a wide spectrum of activity, including antioxidant activity. In this study, we evaluated the effect of hexane:ethanol (2:8) PL extract (subfraction of PL [SPL] extract) on GM-induced hair cell loss in basal, middle and apical regions in a neonatal cochlea cultures. The protective effects of SPL extract were measured by phalloidin staining of cultures from postnatal day 2-3 mice with GM-induced hair cell loss. The anti-apoptosis activity of SPL extract was measured using double labeling by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and myosin-7a staining. The radical-scavenging activity of SPL extract was assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. SPL extract at a concentration of 1 µg/mL significantly inhibited GM-induced hair cell loss at basal and middle region of cochlea, while 5 µg/mL was effective against apical region hair cell loss. The protective effect of SPL extract was concentration dependent and hair cells retained their stereocilia in explants treated with SPL extract prior to treatment with 0.3 mM GM. SPL extract decreased GM-induced apoptosis of hair cells as assessed by TUNEL staining. The outer hair and inner hair counts were not decreased in SPL extract treated groups in compare to GM treated explants. Additionally, SPL extract showed concentration dependent radical scavenging activity in a DPPH assay. An anti-apoptosis effect and potent radical scavenger activity of SPL extract protects from GM-induced hair cell loss at basal, middle and apical regions in neonatal cochlea cultures.
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Interferon-γ-Mediated Natural Killer Cell Activation by an Aqueous Panax ginseng Extract
Takeda, Kazuyoshi; Okumura, Ko
2015-01-01
Panax ginseng extracts are used in traditional herbal medicines, particularly in eastern Asia, but their effect on natural killer (NK) cell activity is not completely understood. This study aimed to examine the effects of P. ginseng extracts on the cytotoxic activity of NK cells. We orally administered P. ginseng extracts or ginsenosides to wild-type (WT) C57BL/6 (B6) and BALB/c mice and to B6 mice deficient in either recombination activating gene 2 (RAG-2) or interferon-γ (IFN-γ). We then tested the cytotoxic activity of NK cells (of spleen and liver mononuclear cells) against NK-sensitive YAC-1 cells. Oral administration of P. ginseng aqueous extract augmented the cytotoxicity of NK cells in WT B6 and BALB/c mice and in RAG-2-deficient B6 mice, but not in IFN-γ-deficient B6 mice. This effect was only observed with the aqueous extract of P. ginseng. Interestingly, the ginsenosides Rb1 and Rg1 did not augment NK cell cytotoxicity. These results demonstrated that the aqueous P. ginseng extract augmented NK cell activation in vivo via an IFN-γ-dependent pathway. PMID:26649061
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Vahedi Larijani, Laleh; Ghasemi, Maryam; AbedianKenari, Saeid; Naghshvar, Farshad
2014-01-01
Most patients with gastrointestinal cancers refer to the health centers at advanced stages of the disease and conventional treatments are not significantly effective for these patients. Therefore, using modern therapeutic approaches with lower toxicity bring higher chance for successful treatment and reduced adverse effects in such patients. The aim of this study is to evaluate the effect of avocado fruit extracts on inhibition of the growth of cancer cells in comparison with normal cells. In an experimental study, ethanol, chloroform, ethyl acetate, and petroleum extracts of avocado (Persea americana) fruit were prepared. Then, the effects if the extracts on the growth of esophageal squamous cell carcinoma and colon adenocarcinoma cell lines were evaluated in comparison with the control group using the MTT test in the cell culture medium. Effects of the four extracts of avocado fruit on three cells lines of peripheral blood mononuclear cells, esophageal squamous cell carcinoma, and colon adenocarcinoma were tested. The results showed that avocado fruit extract is effective in inhibition of cancer cell growth in comparison with normal cells (P<0.05). Avocado fruit is rich in phytochemicals, which play an important role in inhibition of growth of cancer cells. The current study for the first time demonstrates the anti-cancer effect of avocado fruit extracts on two cancers common in Iran. Therefore, it is suggested that the fruit extracts can be considered as appropriate complementary treatments in treatment of esophageal and colon cancers.
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Aguiñiga-Sánchez, Itzen; Soto-Hernández, Marcos; Cadena-Iñiguez, Jorge; Ruíz-Posadas, Lucero del Mar; Cadena-Zamudio, Jorge David; González-Ugarte, Ana Karen; Steider, Benny Weiss; Santiago-Osorio, Edelmiro
2015-01-01
The antiproliferative potential of a crude extract from the chayote hybrid H-837-07-GISeM® and its potential for apoptosis induction were assessed in leukaemic cell lines and normal mouse bone marrow mononuclear cells (BM-MNCs). The extract strongly inhibited the proliferation of the P388, J774, and WEHI-3 cell lines (with an IC50 below 1.3 μg·mL(-1)), reduced cell viability, and induced apoptotic body production, phosphatidylserine translocation, and DNA fragmentation. However, the extract had no effect on BM-MNCs. We postulate that these properties make the extract a good candidate for an anti-tumour agent for clinical use.
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Tuning B cell responses to antigens by cell polarity and membrane trafficking.
Del Valle Batalla, Felipe; Lennon-Dumenil, Ana-María; Yuseff, María-Isabel
2018-06-20
The capacity of B lymphocytes to produce specific antibodies, particularly broadly neutralizing antibodies that provide immunity to viral pathogens has positioned them as valuable therapeutic targets for immunomodulation. To become competent as antibody secreting cells, B cells undergo a series of activation steps, which are triggered by the recognition of antigens frequently displayed on the surface of other presenting cells. Such antigens elicit the formation of an immune synapse (IS), where local cytoskeleton rearrangements coupled to mechanical forces and membrane trafficking orchestrate the extraction and processing of antigens in B cells. In this review, we discuss the molecular mechanisms that regulate polarized membrane trafficking and mechanical properties of the immune synapse, as well as the potential extracellular cues from the environment, which may impact the ability of B cells to sense and acquire antigens at the immune synapse. An integrated view of the diverse cellular mechanisms that shape the immune synapse will provide a better understanding on how B cells are efficiently activated. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Design and optimization of a semicontinuous hot-cold extraction of polyphenols from grape pomace.
Monrad, Jeana K; Srinivas, Keerthi; Howard, Luke R; King, Jerry W
2012-06-06
Grape pomace contains appreciable amounts of polyphenolic compounds such as anthocyanins and procyanidins which can be recovered for use as food supplements. The extraction of these polyphenols from the pomace is usually accomplished at slightly elevated temperatures, frequently employing hydroethanolic solvents. Due to governmental regulations and the cost involved in using ethanol as a solvent, as well as the loss in polyphenolics due to thermal degradation, improved extraction techniques are required. In this study, a semicontinuous extraction apparatus employing only water was developed to maximize the recovery of anthocyanins and procyanidins from red grape pomace (Vitis vinifera). Water is preheated prior to its entry to the extraction cell containing the grape pomace sample, where it is allowed to then flow continuously through the unheated extraction vessel prior to its collection at ambient conditions. Extraction variables that impacted the polyphenolic recovery included pomace moisture content (crude or dried), sample mass, water flow rate, and extraction temperature. A response surface method was used to analyze the results from the extraction, and the optimal conditions were found to be 140 °C and 9 mL/min water flow rate. These conditions can produce an extract containing 130 mg/100 g DW of anthocyanins and 2077 mg/100 g DW of procyanidins. Higher yields of polyphenolics were observed using crude (wet) rather than dried pomace, hence avoiding the need to dry the pomace prior to extraction. The described semicontinuous extraction method using only water as the extraction solvent under subcritical conditions allowed the efficient extraction of polyphenols from red grape pomace without the attendant loss of polyphenolic content due to having to heat the extraction vessel prior to commencement of extraction.
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Urry, Zoe L; Richards, David F; Black, Cheryl; Morales, Maria; Carnés, Jerónimo; Hawrylowicz, Catherine M; Robinson, Douglas S
2014-05-29
Allergen immunotherapy (SIT) is the only treatment for allergic disease capable of modifying disease long term. To reduce the risk of anaphylaxis from SIT, allergen-extracts have been modified by polymerisation with glutaraldehyde to reduce IgE binding. It is suggested that these allergoid extracts also have reduced T cell activity, which could compromise clinical efficacy. Effective SIT is thought to act through regulatory T cells (Tregs) rather than activation of effector T cells. There is no published data on the activity of modified extracts on Tregs. We compared the capacity of modified (depigmented-polymerised) versus unmodified (native) allergen extracts of grass pollen and house dust mite to stimulate proliferation/cytokine production and to modulate Treg/effector T cell frequency in cultures of peripheral blood mononuclear cells (PBMC), from volunteers sensitised to both allergens in vitro. Depigmented-polymerised allergen extracts stimulated less proliferation of PBMC, and reduced effector cell numbers after 7 days in culture than did native extracts. However, the frequency of Foxp3+ Tregs in cultures were similar to those seen with native extract so that ratios of regulatory to effector T cells were significantly increased in cultures stimulated with depigmented-polymerised extracts. Addition of 1α, 25-dihydroxyvitamin D3 further favoured Treg, and reduced effector cytokine production, but not interleukin-10. Depigmented-polymerised allergen extracts appear to favour Treg expansion over activation of effector T cells and this may relate to their demonstrated efficacy and safety in SIT. 1α, 25-dihydroxyvitamin D3 further reduces effector T cell activation by allergen extracts and may be a useful adjuvant for SIT.
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2014-01-01
Background Allergen immunotherapy (SIT) is the only treatment for allergic disease capable of modifying disease long term. To reduce the risk of anaphylaxis from SIT, allergen-extracts have been modified by polymerisation with glutaraldehyde to reduce IgE binding. It is suggested that these allergoid extracts also have reduced T cell activity, which could compromise clinical efficacy. Effective SIT is thought to act through regulatory T cells (Tregs) rather than activation of effector T cells. There is no published data on the activity of modified extracts on Tregs. Results We compared the capacity of modified (depigmented-polymerised) versus unmodified (native) allergen extracts of grass pollen and house dust mite to stimulate proliferation/cytokine production and to modulate Treg/effector T cell frequency in cultures of peripheral blood mononuclear cells (PBMC), from volunteers sensitised to both allergens in vitro. Depigmented-polymerised allergen extracts stimulated less proliferation of PBMC, and reduced effector cell numbers after 7 days in culture than did native extracts. However, the frequency of Foxp3+ Tregs in cultures were similar to those seen with native extract so that ratios of regulatory to effector T cells were significantly increased in cultures stimulated with depigmented-polymerised extracts. Addition of 1α, 25-dihydroxyvitamin D3 further favoured Treg, and reduced effector cytokine production, but not interleukin-10. Conclusions Depigmented-polymerised allergen extracts appear to favour Treg expansion over activation of effector T cells and this may relate to their demonstrated efficacy and safety in SIT. 1α, 25-dihydroxyvitamin D3 further reduces effector T cell activation by allergen extracts and may be a useful adjuvant for SIT. PMID:24884430
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This SOP summarizes the method for extracting and preparing a hard floor surface wipe or food preparation surface wipe sample for analysis of neutral persistent organic. It covers the extraction and concentration of samples that are to be analyzed by gas chromatography/mass spect...
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Strzemski, Maciej; Wojnicki, Kamil; Sowa, Ireneusz; Wojas-Krawczyk, Kamila; Krawczyk, Paweł; Kocjan, Ryszard; Such, Justyna; Latalski, Michał; Wnorowski, Artur; Wójciak-Kosior, Magdalena
2017-01-01
Various species of the Carlina genus have been used in traditional medicine in many countries to treat numerous skin disorders, including cancer. The objective of this work was to assess the anticancer properties of root and leaf extracts from Carlina acaulis subsp. caulescens and C. acanthifolia subsp. utzka. Anti-tumor properties of the extracts were explored using a tetrazolium-based cell viability assay and flow cytometric apoptosis analysis, followed by immunodetection of phosphoactive ERK1/2 in UACC-903, C32, and UACC-647 human melanoma cell lines. Normal human fibroblasts were used as a control. Leaf extracts inhibited the viability of all tested melanoma cell lines in a dose-dependent fashion while the fibroblasts were less sensitive to such extract. The root extracts inhibited the proliferation of UACC-903 and UACC-647 cells only at the highest doses (300 μg/mL). However, the C32 and fibroblast cells exhibited an increase in the cellular proliferation rate and no caspase activity was observed in response to the root extracts (100 μg/mL). An increase in caspase activity was observed in melanoma cells treated with the leaf extracts of both Carlina species. Leaf extracts from C. acaulis subsp. caulescens (100 μg/mL) inhibited proliferatory ERK1/2 in UACC-903 and C32 cells, as demonstrated by the decrease in ERK1/2 phosphorylation. No reduction in phospho-ERK1/2 was observed in the tested cell lines treated with the root extracts, apart from UACC-647 after incubation with the C. acanthifolia subsp. utzka root extract (100 μg/mL). There was no change in ERK1/2 phosphorylation in the fibroblasts. The extracts from the leaves and roots were analyzed by HPLC and the analysis showed the presence of triterpenes and phenolic acids as the main extract components. The research demonstrated that the extracts from the leaves of the plants were cytotoxic against the human melanoma line and induced apoptosis of the cells. The triterpene fraction present in the tested extracts may be responsible for this activity. PMID:28659804
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Marvibaigi, Mohsen; Amini, Neda; Supriyanto, Eko; Abdul Majid, Fadzilah Adibah; Kumar Jaganathan, Saravana; Jamil, Shajarahtunnur; Hamzehalipour Almaki, Javad; Nasiri, Rozita
2016-01-01
Scurrula ferruginea (Jack) Danser is one of the mistletoe species belonging to Loranthaceae family, which grows on the branches of many deciduous trees in tropical countries. This study evaluated the antioxidant activities of S. ferruginea extracts. The cytotoxic activity of the selected extracts, which showed potent antioxidant activities, and high phenolic and flavonoid contents, were investigated in human breast cancer cell line (MDA-MB-231) and non-cancer human skin fibroblast cells (HSF-1184). The activities and characteristics varied depending on the different parts of S. ferruginea, solvent polarity, and concentrations of extracts. The stem methanol extract showed the highest amount of both phenolic (273.51 ± 4.84 mg gallic acid/g extract) and flavonoid contents (163.41 ± 4.62 mg catechin/g extract) and strong DPPH• radical scavenging (IC50 = 27.81 μg/mL) and metal chelation activity (IC50 = 80.20 μg/mL). The stem aqueous extract showed the highest ABTS•+ scavenging ability. The stem methanol and aqueous extracts exhibited dose-dependent cytotoxic activity against MDA-MB-231 cells with IC50 of 19.27 and 50.35 μg/mL, respectively. Furthermore, the extracts inhibited the migration and colony formation of MDA-MB-231 cells in a concentration-dependent manner. Morphological observations revealed hallmark properties of apoptosis in treated cells. The methanol extract induced an increase in ROS generation and mitochondrial depolarization in MDA-MB-231 cells, suggesting its potent apoptotic activity. The present study demonstrated that the S. ferruginea methanol extract mediated MDA-MB-231 cell growth inhibition via induction of apoptosis which was confirmed by Western blot analysis. It may be a potential anticancer agent; however, its in vivo anticancer activity needs to be investigated. PMID:27410459
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Khacha-Ananda, Supakit; Tragoolpua, Khajornsak; Chantawannakul, Panuwan; Tragoolpua, Yingmanee
2016-12-01
The continual increase in mortality rates and number of cancer cases is a matter of serious concern in developing countries. The incorporation of natural products into classical cancer treatment approaches is a promising direction. The mechanisms of A549 and HeLa cancer cell death induction by ethanolic extracts of propolis samples from Phayao, Chiang Mai, and Nan provinces in northern Thailand were investigated in this study. The propolis extract from Chiang Mai showed the highest antioxidant activity and the greatest total phenolic content. The propolis extract from Nan also exhibited the highest total flavonoid content. The proliferation of A549 and HeLa cells grown in the presence of the propolis extracts was suppressed in a dose- and time-dependent manner. Moreover, treatment of both cancer cells with the propolis extracts showed DNA fragmentation and significantly increased the number of the apoptotic cells. On A549 cells, the extrinsic and intrinsic pathways of caspase enzymes were activated by the propolis extracts from Phayao and Chiang Mai. In the case of the propolis extract from Nan, the mechanisms involved apoptosis on the A549 cells were caspase-independent pathway. The extrinsic pathway of the caspase enzyme was triggered by all of the propolis extracts on HeLa cells. Finally, oral administration of the propolis granule produced from the propolis extract from Nan resulted in extended survival of tumour-bearing mice. Therefore, propolis extracts from the northern region of Thailand demonstrated pharmacological properties, both antioxidant and anticancer activities. From these findings, it is evident that propolis extracts can be considered as a naturally obtained agent extremely useful in cancer treatment.
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Remus, Daniela M.; Bongers, Roger S.; Meijerink, Marjolein; Fusetti, Fabrizia; Poolman, Bert; de Vos, Paul; Wells, Jerry M.; Bron, Peter A.
2013-01-01
Sortases are transpeptidases that couple surface proteins to the peptidoglycan of Gram-positive bacteria, and several sortase-dependent proteins (SDPs) have been demonstrated to be crucial for the interactions of pathogenic and nonpathogenic bacteria with their hosts. Here, we studied the role of sortase A (SrtA) in Lactobacillus plantarum WCFS1, a model Lactobacillus for probiotic organisms. An isogenic srtA deletion derivative was constructed which did not show residual SrtA activity. DNA microarray-based transcriptome analysis revealed that the srtA deletion had only minor impact on the full-genome transcriptome of L. plantarum, while the expression of SDP-encoding genes remained completely unaffected. Mass spectrometry analysis of the bacterial cell surface proteome, which was assessed by trypsinization of intact bacterial cells and by LiCl protein extraction, revealed that SrtA is required for the appropriate subcellular location of specific SDPs and for their covalent coupling to the cell envelope, respectively. We further found that SrtA deficiency did not affect the persistence and/or survival of L. plantarum in the gastrointestinal tract of mice. In addition, an in vitro immature dendritic cell (iDC) assay revealed that the removal of surface proteins by LiCl strongly affected the proinflammatory signaling properties of the SrtA-deficient strain but not of the wild type, which suggests a role of SDPs in host immune response modulation. PMID:23175652
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Endophytic bacteria take the challenge to improve Cu phytoextraction by sunflower.
Kolbas, Aliaksandr; Kidd, Petra; Guinberteau, Jacques; Jaunatre, Renaud; Herzig, Rolf; Mench, Michel
2015-04-01
Endophytic bacteria from roots and crude seed extracts of a Cu-tolerant population of Agrostis capillaris were inoculated to a sunflower metal-tolerant mutant line, and their influence on Cu tolerance and phytoextraction was assessed using a Cu-contaminated soil series. Ten endophytic bacterial strains isolated from surface-sterilized A. capillaris roots were mixed to prepare the root endophyte inoculant (RE). In parallel, surface-sterilized seeds of A. capillaris were crushed in MgSO4 to prepare a crude seed extract containing seed endophytes (SE). An aliquot of this seed extract was filtered at 0.2 μm to obtain a bacterial cell-free seed extract (SEF). After surface sterilization, germinated sunflower seeds were separately treated with one of five modalities: no treatment (C), immersion in MgSO4 (CMg) or SEF solutions and inoculation with RE or SE. All plants were cultivated on a Cu-contaminated soil series (13-1020 mg Cu kg(-1)). Cultivable RE strains were mostly members of the Pseudomonas genera, and one strain was closely related to Labrys sp. The cultivable SE strains belonged mainly to the Bacillus genera and some members of the Rhodococcus genera. The treatment effects depended on the soil Cu concentration. Both SE and SEF plants had a higher Cu tolerance in the 13-517 mg Cu kg(-1) soil range as reflected by increased shoot and root DW yields compared to control plants. This was accompanied by a slight decrease in shoot Cu concentration and increase in root Cu concentration. Shoot and root DW yields were more promoted by SE than SEF in the 13-114 mg Cu kg(-1) soil range, which could reflect the influence of seed-located bacterial endophytes. At intermediate soil Cu (416-818 mg Cu kg(-1) soil), the RE and CMg plants had lower shoot Cu concentrations than the control, SE and SEF plants. At high total soil Cu (617-1020 mg Cu kg(-1)), root DW yield of RE plants slightly increased and their root Cu concentration rose by up to 1.9-fold. In terms of phytoextraction efficiency, shoot Cu removal was increased for sunflower plants inoculated with crude and bacterial cell-free seed extracts by 1.3- to 2.2-fold in the 13-416 mg Cu kg(-1) soil range. Such increase was mainly driven by an enhanced shoot DW yield. The number and distribution of endophytic bacteria in the harvested sunflower tissues must be further examined.
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JUNG, IL LAE; LEE, JU HYE; KANG, SE CHAN
2015-01-01
It has previously been reported that cold water-extracts of Moringa oleifera leaf have anticancer activity against various human cancer cell lines, including non-small cell lung cancer. In the present study, the anticancer activity of M. oleifera leaf extracts was investigated in human hepatocellular carcinoma HepG2 cells. By the analysis of apoptotic signals, including the induction of caspase or poly(ADP-ribose) polymerase cleavage, and the Annexin V and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assays, it was demonstrated that M. oleifera leaf extracts induce the apoptosis of HepG2 cells. In the hollow fiber assay, oral administration of the leaf extracts significantly reduced (44–52%) the proliferation of the HepG2 cells and A549 non-small cell lung cancer cells. These results support the potential of soluble extracts of M. oleifera leaf as orally administered therapeutics for the treatment of human liver and lung cancers. PMID:26622717
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Tayarani-Najaran, Zahra; Sareban, Mahla; Gholami, Atefeh; Emami, Seyed Ahmad; Mojarrab, Mahdi
2013-01-01
Artemisia is an important genus of Iranian flora. Cytotoxic activities for some species of the genus have already been reported. In this study, we have investigated the cytotoxic effects of n-hexane, CH2Cl2, EtOAc, EtOH, and EtOH/H2O (1 : 1) extracts of A. turanica Krasch. on two human leukemic cancer cell lines (K562 and HL-60) and J774 as normal cells using alamarBlue (resazurin) assay. PI staining of the fragmented DNA and western blot analysis were used to evaluate the possible apoptotic effect of the extract. The CH2Cl2 extract of A. turanica showed the most antiproliferative effect on cancer cells among all tested extracts with IC50 values of 69 and 104 μg/mL on K562 and HL-60 cells, respectively, whereas the normal cells were not affected significantly by this extract. Sub-G1 peak in the flow cytometry histogram of the cells treated with CH2Cl2 extract of A. turanica and cleavage of PARP protein confirmed the induction of apoptosis with CH2Cl2 extract. Taken together, the findings of the present work suggest the anticancer potential of CH2Cl2 extract of A. turanica on human leukemic cancer cell lines. PMID:24288497
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Li, Weiling; Li, Ye; Zhao, Yuwan; Yuan, Jieli; Mao, Weifeng
2014-01-01
To observe the inhibition effects of the Buthus matensii Karsch (BmK) scorpion venom extracts on the growth of human breast cancer MCF-7 cells, and to explore its mechanisms. Two common tumor cells (SMMC7721, MCF-7) were examined for the one which wasmore sensitivity to scorpion venom by MTT method. Cell cycle was determined by flow cytometry. Immunocytochemistry was applied to detect apoptosis-related protein Caspase-3 and Bcl-2 levels, while the expression of cell cycle-related protein Cyclin D1 was shown by Western blotting. Our data indicated that MCF-7 was the more sensitive cell line to scorpion venom. The extracts of scorpion venom could inhibit the growth and proliferation of MCF-7 cells. Furthermore, the extract of scorpion venom induced apoptosis through Caspase-3 up-regulation while Bcl-2 down-regulation in MCF-7 cells. In addition, the extracts of scorpion venom blocked the cells from G0/G1 phase to S phase and decreased cell cycle-related protein Cyclin D1 level after drug intervention compared with the negative control group. These results showed that the BmK scorpion venom extracts could inhibit the growth of MCF-7 cells by inducing apoptosis and blocking cell cycle in G0/G1 phase. The BmK scorpion venom extracts will be very valuable for the treatment of breast cancer.
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Dinicola, Simona; Cucina, Alessandra; Pasqualato, Alessia; D'Anselmi, Fabrizio; Proietti, Sara; Lisi, Elisabetta; Pasqua, Gabriella; Antonacci, Donato; Bizzarri, Mariano
2012-01-01
Grape seed extract has been proven to exert anticancer effects on different tumors. These effects are mainly ascribed to catechin and procyanidin content. Analytical studies demonstrated that grape seed extract composition is complex and it is likely other components could exert biological activities. Using cell count and flow cytometry assays, we evaluated the cytostatic and apoptotic effects produced by three different grape seed extracts from Italia, Palieri and Red Globe cultivars, on Caco2 and HCT-8 colon cancer cells. These effects were compared to those induced by epigallocatechin and procyanidins, alone or in association, on the same cell lines. All the extracts induced growth inhibition and apoptosis in Caco2 and HCT-8 cells, along the intrinsic apoptotic pathway. On both cell lines, growth inhibition induced by Italia and Palieri grape seed extracts was significantly higher than that it has been recorded with epigallocatechin, procyanidins and their association. In Caco2 cells, the extract from Red Globe cultivar was less effective in inducing growth inhibition than procyanidins alone and in association with epigallocatechin, whereas, in HCT-8 cells, only the association of epigallocatechin and procyanidins triggers a significant proliferation decrease. On both cell lines, apoptosis induced by Italia, Palieri and Red Globe grape seed extracts was considerably higher than has been recorded with epigallocatechin, procyanidins and their association. These data support the hypothesis by which other compounds, present in the grape seed extracts, are likely to enhance the anticancer effects.
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Dinicola, Simona; Cucina, Alessandra; Pasqualato, Alessia; D’Anselmi, Fabrizio; Proietti, Sara; Lisi, Elisabetta; Pasqua, Gabriella; Antonacci, Donato; Bizzarri, Mariano
2012-01-01
Grape seed extract has been proven to exert anticancer effects on different tumors. These effects are mainly ascribed to catechin and procyanidin content. Analytical studies demonstrated that grape seed extract composition is complex and it is likely other components could exert biological activities. Using cell count and flow cytometry assays, we evaluated the cytostatic and apoptotic effects produced by three different grape seed extracts from Italia, Palieri and Red Globe cultivars, on Caco2 and HCT-8 colon cancer cells. These effects were compared to those induced by epigallocatechin and procyanidins, alone or in association, on the same cell lines. All the extracts induced growth inhibition and apoptosis in Caco2 and HCT-8 cells, along the intrinsic apoptotic pathway. On both cell lines, growth inhibition induced by Italia and Palieri grape seed extracts was significantly higher than that it has been recorded with epigallocatechin, procyanidins and their association. In Caco2 cells, the extract from Red Globe cultivar was less effective in inducing growth inhibition than procyanidins alone and in association with epigallocatechin, whereas, in HCT-8 cells, only the association of epigallocatechin and procyanidins triggers a significant proliferation decrease. On both cell lines, apoptosis induced by Italia, Palieri and Red Globe grape seed extracts was considerably higher than has been recorded with epigallocatechin, procyanidins and their association. These data support the hypothesis by which other compounds, present in the grape seed extracts, are likely to enhance the anticancer effects. PMID:22312277
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Optimized in vitro procedure for assessing the cytocompatibility of magnesium-based biomaterials.
Jung, Ole; Smeets, Ralf; Porchetta, Dario; Kopp, Alexander; Ptock, Christoph; Müller, Ute; Heiland, Max; Schwade, Max; Behr, Björn; Kröger, Nadja; Kluwe, Lan; Hanken, Henning; Hartjen, Philip
2015-09-01
Magnesium (Mg) is a promising biomaterial for degradable implant applications that has been extensively studied in vitro and in vivo in recent years. In this study, we developed a procedure that allows an optimized and uniform in vitro assessment of the cytocompatibility of Mg-based materials while respecting the standard protocol DIN EN ISO 10993-5:2009. The mouse fibroblast line L-929 was chosen as the preferred assay cell line and MEM supplemented with 10% FCS, penicillin/streptomycin and 4mM l-glutamine as the favored assay medium. The procedure consists of (1) an indirect assessment of effects of soluble Mg corrosion products in material extracts and (2) a direct assessment of the surface compatibility in terms of cell attachment and cytotoxicity originating from active corrosion processes. The indirect assessment allows the quantification of cell-proliferation (BrdU-assay), viability (XTT-assay) as well as cytotoxicity (LDH-assay) of the mouse fibroblasts incubated with material extracts. Direct assessment visualizes cells attached to the test materials by means of live-dead staining. The colorimetric assays and the visual evaluation complement each other and the combination of both provides an optimized and simple procedure for assessing the cytocompatibility of Mg-based biomaterials in vitro. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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Zhang, Erlin; Chen, Haiyan; Shen, Feng
2010-07-01
Biocorrosion properties and blood- and cell compatibility of pure iron were studied in comparison with 316L stainless steel and Mg-Mn-Zn magnesium alloy to reveal the possibility of pure iron as a biodegradable biomaterial. Both electrochemical and weight loss tests showed that pure iron showed a relatively high corrosion rate at the first several days and then decreased to a low level during the following immersion due to the formation of phosphates on the surface. However, the corrosion of pure iron did not cause significant increase in pH value to the solution. In comparison with 316L and Mg-Mn-Zn alloy, the pure iron exhibited biodegradable property in a moderate corrosion rate. Pure iron possessed similar dynamic blood clotting time, prothrombin time and plasma recalcification time to 316L and Mg-Mn-Zn alloy, but a lower hemolysis ratio and a significant lower number density of adhered platelets. MTT results revealed that the extract except the one with 25% 24 h extract actually displayed toxicity to cells and the toxicity increased with the increasing of the iron ion concentration and the incubation time. It was thought there should be an iron ion concentration threshold in the effect of iron ion on the cell toxicity.