Silicon Dissolution from Microporous Silicon Substituted Hydroxyapatite and its Effect on Osteoblast Behaviour

2006 ◽  
Vol 309-311 ◽  
pp. 117-120 ◽  
Author(s):  
Katharina Guth ◽  
Tom Buckland ◽  
Karen A. Hing
Keyword(s):  
Significant Variation ◽  
Direct Contact ◽  
Culture Medium ◽  
Initial Level ◽  
Culture Conditions ◽  
Dynamic Conditions ◽  
Medium Change ◽  
Static Conditions ◽  
Silicon Dissolution ◽  
Apatite Lattice

In this study silicon release from SiHA into tissue culture medium was investigated under static and semi-dynamic conditions. The effect of silicon release under semi-dynamic conditions on alkaline phosphatase activity (ALP) and collagen I (CICP) expression by osteoblast like cells (HOS TE85) was also examined. Under static conditions a low level of silicon was released within 24 hours, this initial level dropped over 3-7 days but subsequently increased again by 10-14 days. Under semi-dynamic conditions silicon was released within 24 hours and was subsequently reduced with each medium change until equilibrating at close to 0 after 10 days. ALP and CICP showed significant variation in expression between culture conditions. In direct contact with SiHA ALP peaked at day 10 and CICP was constantly elevated. Cells grown in the presence of but not on SiHA expressed progressively decreasing levels of ALP from 7-14 days, with CICP peaking at day 10. On thermanox (TMX) ALP constantly increased and CICP peaked at day 10. The results indicate that silicon leaches out of the lattice of the SiHA crystal structure but may also be reprecipitated onto the substrate. We have also demonstrated that Si influences osteoblast metabolism and differentiation whether it is available as free silicon or 'bound' in the apatite lattice.

scholarly journals Mimicking of Blood Flow Results in a Distinct Functional Phenotype in Human Non-Adherent Classical Monocytes

Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 748
Author(s):  
Elisa Wirthgen ◽  
Melanie Hornschuh ◽  
Ida Maria Wrobel ◽  
Christian Manteuffel ◽  
Jan Däbritz
Keyword(s):  
Blood Flow ◽  
Shear Flow ◽  
Ex Vivo ◽  
Culture Conditions ◽  
Inflammatory Signaling ◽  
Gm Csf ◽  
Beneficial Effects ◽  
Migratory Capacity ◽  
Ex Vivo Culture ◽  
Static Conditions

Ex vivo culture conditions during the manufacturing process impact the therapeutic effect of cell-based products. Mimicking blood flow during ex vivo culture of monocytes has beneficial effects by preserving their migratory ability. However, the effects of shear flow on the inflammatory response have not been studied so far. Hence, the present study investigates the effects of shear flow on both blood-derived naïve and activated monocytes. The activation of monocytes was experimentally induced by granulocyte-macrophage colony-stimulating factor (GM-CSF), which acts as a pro-survival and growth factor on monocytes with a potential role in inflammation. Monocytes were cultured under dynamic (=shear flow) or static conditions while preventing monocytes' adherence by using cell-repellent surfaces to avoid adhesion-induced differentiation. After cultivation (40 h), cell size, viability, and cytokine secretion were evaluated, and the cells were further applied to functional tests on their migratory capacity, adherence, and metabolic activity. Our results demonstrate that the application of shear flow resulted in a decreased pro-inflammatory signaling concurrent with increased secretion of the anti-inflammatory cytokine IL-10 and increased migratory capacity. These features may improve the efficacy of monocyte-based therapeutic products as both the unwanted inflammatory signaling in blood circulation and the loss of migratory ability will be prevented.

Study on Optimization of Fermentation Condition for Nitrilase-Producer Escherichia Coli BL21 (DE3)/pET-Nit

2011 ◽  
Vol 175-176 ◽  
pp. 192-196 ◽  
Author(s):  
Li Li Feng ◽  
Jian Fei Zhang ◽  
Hui Luo ◽  
Zheng Li ◽  
Hong Jie Zhang
Keyword(s):  
Escherichia Coli ◽  
Recombinant Strain ◽  
Culture Medium ◽  
Culture Conditions ◽  
Fermentation Condition ◽  
Hydrogen Phosphate ◽  
Strain Bl21 ◽  
Initial Ph ◽  
Potassium Hydrogen ◽  
Optimization Of Fermentation

The paper concentrated on the optimization of the recombinant strain BL21 (DE3)-PE7-Nit. The component of culture medium and the culture conditions were optimized. The optimized medium was: yeast extract 10 g/l, L-glutamate sodium 8 g/l, MgSO4.7H2O 0.7 g/l, Isopropyl-β-D-thiogalactopyranoside 0.3 mmol/L, potassium hydrogen phosphate 0.5 g / L, phosphate Potassium 0.5 g / L and the culture condition was: initial pH 7.0, inoculum 2%. The result showed that the activity of nitrilase prepared with these conditions increased by 130.37 % through optimization.

scholarly journals Sensitive and Selective Culture Medium for Detection of Environmental Clostridium difficile Isolates without Requirement for Anaerobic Culture Conditions

2014 ◽  
Vol 52 (9) ◽  
pp. 3259-3263 ◽  
Author(s):  
Jennifer L. Cadnum ◽  
Kelly N. Hurless ◽  
Abhishek Deshpande ◽  
Michelle M. Nerandzic ◽  
Sirisha Kundrapu ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Culture Medium ◽  
Culture Conditions ◽  
Anaerobic Culture ◽  
Selective Culture Medium

scholarly journals The Effect of Various Hydroxide and Salt Additives on the Reduction of Fluoride Ion Mobility in Industrial Waste

2021 ◽  
Vol 13 (3) ◽  
pp. 1554
Author(s):  
Tadas Dambrauskas ◽  
Kestutis Baltakys ◽  
Agne Grineviciene ◽  
Valdas Rudelis
Keyword(s):  
Liquid Medium ◽  
Silica Gel ◽  
Ion Mobility ◽  
Fluoride Removal ◽  
Dynamic Conditions ◽  
Treatment Conditions ◽  
Medium Flow ◽  
Silica Gel Waste ◽  
Fluorine Ions ◽  
Static Conditions

In this work, the influence of various hydroxide and salt additives on the removal of F− ions from silica gel waste, which is obtained during the production of AlF3, was examined. The leaching of the mentioned ions from silica gel waste to the liquid medium was achieved by the application of different techniques: (1) leaching under static conditions; (2) leaching under dynamic conditions by the use of continuous liquid medium flow; and (3) leaching in cycles under dynamic conditions. It was determined that the efficiency of the fluoride removal from this waste depends on the w/s ratio, the leaching conditions, and the additives used. It was proven that it is possible to reduce the concentration of fluorine ions from 10% to <5% by changing the treatment conditions and by adding alkaline compounds. The silica gel obtained after the leaching is a promising silicon dioxide source.

A New Technical Standard Procedure to Measure Stimulation and Gravel-pack Fluid Leak-off under Dynamic Conditions

2015 ◽  
Author(s):  
Mahmoud Asadi ◽  
Brain Ainley ◽  
David Archacki ◽  
Eric Aubry ◽  
Harold Brannon ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Standard Procedure ◽  
Oil And Gas Industry ◽  
Testing Procedure ◽  
Technical Standard ◽  
Gas Wells ◽  
Dynamic Conditions ◽  
Oil And Gas Wells ◽  
Static Conditions ◽  
Gravel Pack

Abstract Historically, leak-off analyses of stimulation fluids have been performed using in-house laboratory procedures. The lack of industry standard procedures to perform leak-off and wall building coefficient analyses of stimulation fluids has introduced inconsistency in both results and reporting for many years. A technical standard adopted in 2006 by both API and ISO for static conditions has provided the oil and gas industry with the first standardized procedure to measure and report leak-off1. However, the more complex testing under dynamic conditions was not addressed. As a result, a group of industry experts have compiled their years of experiences in developing a new technical standard to measure the leak-off characteristics of stimulation and gravel-pack fluids under dynamic flow conditions. Stimulation and gravel-pack fluids are defined, for the purpose of this technical standard, as fluids used to enhance production from oil and gas wells by fracturing and fluids used to place filtration media to control formation sand production from oil and gas wells. Leak-off is the amount of fluid lost to porous media during these operations. The leak-off procedure was developed through the colaberation of several industry companies by evaluating numerous in-house laboratory techniques and conducting round robin testing to ensure that any modifications to these procedures were reliable and repeatable. The new standard provides a step-by-step procedure that includes fluid preparation, experimental equipment design, testing procedure and data analyses for fluids exhibiting viscosity controlled leak-off or wall building characteristics. Example calculations are reviewed within this paper.

Effect of yolk-sac antibody on rat embryos grown in culture

Development ◽  
1972 ◽  
Vol 27 (3) ◽  
pp. 543-553
Author(s):  
D. A. T. New ◽  
R. L. Brent
Keyword(s):  
Direct Contact ◽  
Culture Medium ◽  
Gamma Globulin ◽  
Yolk Sac ◽  
Amniotic Cavity ◽  
Pregnant Rats ◽  
Rat Embryos ◽  
Visceral Yolk Sac ◽  
Primary Action

Rat embryos, explanted with their embryonic membranes during the early stages of organogenesis ( days gestation), were grown in culture in roller tubes. Yolk-sac antibody (sheep anti rat yolk-sac gamma globulin), known to be teratogenic when injected into pregnant rats, was added to the culture medium. At concentrations of 0·1 mg/ml or more the antibody caused gross retardation of growth and differentiation. Injection of antibody into the amniotic cavity so that it had direct contact with the embryo, or between the amnion and yolk sac so that it was in contact with the mesodermal surface of the yolk sac, had little or no effect on development of the embryo or its membranes. These in vitro experiments indicate that yolk-sac antibody has an effect on development independent of any immunological reaction of the mother, and the primary action is probably on the visceral yolk-sac endoderm.

Inhibition of proliferative growth in glioma cells by calmodulin antagonists

1986 ◽  
Vol 65 (1) ◽  
pp. 74-79 ◽  
Author(s):  
Nobuyuki Suzuki ◽  
Tetsuo Kanno ◽  
Yutaka Nagata ◽  
Taiji Kato
Keyword(s):  
Culture Medium ◽  
Deoxyribonucleic Acid ◽  
Control Level ◽  
Glioma Cells ◽  
Culture Conditions ◽  
Calmodulin Antagonists ◽  
High Concentration ◽  
Content Type ◽  
Chemically Induced ◽  
Proliferative Growth

✓ The effects of several calmodulin antagonists, such as N-(6-aminohexyl)-5-chloro-1-naphthalene-sulfonamide hydrochloride (W-7) and its dechlorinated structural analogue (W-5), on the growth and proliferation of cultured and transplanted glioma (GA-1, chemically induced from rat glioblasts) were evaluated. Under culture conditions, the concentration of W-7 necessary to exert 50% inhibition of GA-1 glioma cell growth was 50 µM. However, W-5, with a lower binding affinity to calmodulin than W-7, caused no definite inhibition of the proliferation of GA-1 cells in culture. When a low concentration of W-7 (12.5 µM) was added to the culture medium, deoxyribonucleic acid (DNA) synthesis in the GA-1 glioma cells was not markedly affected, whereas both ribonucleic acid (RNA) and protein syntheses were strongly suppressed on incubation for 24 hours. When a high concentration of W-7 (25.0 to 75.0 µM) was applied to the medium, synthesis of DNA, RNA, and protein was distinctly inhibited. When W-7 (50.0 µM) was added to the incubation medium, the calmodulin concentration in the cultured GA-1 was reduced to as much as half the control level within 2 hours, and thereafter remained at this level. Whereas control rats intraperitoneally transplanted with GA-1 cells could survive for 14 to 21 days, daily intraperitoneal injections of W-7 at concentrations of 1.0, 3.0, and 10.0 mg/kg body weight prolonged the survival span to between 21 and 26 days; this corresponded to an increased life span of about 40% compared to the controls.

scholarly journals Static and Dynamic Performance of Vector Control on Induction Motor with PID Controller: An Investigation on LabVIEW

2021 ◽  
Vol 4 (2) ◽  
pp. 83-96
Author(s):  
Abdillah Aziz Muntashir ◽  
Era Purwanto ◽  
Bambang Sumantri ◽  
Hanif Hasyier FAkhruddin ◽  
Raden Akbar Nur Apriyanto
Keyword(s):  
Vector Control ◽  
Induction Motor ◽  
Pid Controller ◽  
High Reliability ◽  
Load Torque ◽  
Set Point ◽  
Dynamic Conditions ◽  
Low Speed ◽  
Three Phase ◽  
Static Conditions

A three-phase induction motor is often used in everyday life because of its high reliability. However, it is associated with some disadvantages, including difficulties in maintaining constant speed during load changes and speed regulation due to the decoupled system. Therefore, this study aims to adjust the three-phase induction motor control to become a separate amplifier DC motor by setting the vector control using the IFOC method, which changes the coupled to the decoupled system. The speed settings are equipped with a PID controller where its parameters, which are obtained using Ziegler Nichols, produce speed output with fast research time and small steady-state errors. This research was conducted to observe and analyze the performance of a controller based on the IFOC approach with a PID controller at speed differences, with static and dynamic conditions in the entire speed working area. In the first stage of the research, simulation is carried out with static conditions, namely changes in speed variations throughout the work area (low speed to high speed), the next stage is a simulation with dynamic conditions, which is to provide changes in the value of the load torque when the system is operating. The simulation result carried out with LabVIEW shows a response time of 1.13 ms, a settling time of 9.9 ms, and a steady error of 0.4% at the 500 Rpm set point. It also indicated dynamic characteristics with a recovery time of 4.9 ms at the 300 Rpm set point. When operated at low speed, IFOC with PID controller has a stable response. But In dynamic conditions, the use of a PID controller is considered unsuitable. This is because the PID controller is less fast and less robust in responding to the system when conditions change in the value of the load torque.

scholarly journals On some pre-Cambrian metadolerites from the central Ivigtut region SW Greenland

1965 ◽  
Vol 52 ◽  
pp. 1-42
Author(s):  
E Bondesen ◽  
N Henriksen
Keyword(s):  
Shear Zones ◽  
Metamorphic Grade ◽  
Amphibolite Facies ◽  
Dynamic Conditions ◽  
Static Conditions

After their consolidation, the Ketilidian gneisses were transversed by several generations of tensional, doleritic dykes-the Kuánitic dykes. During a later episode (the Sánerutian) these dykes were metamorphosed to varying degrees of alteration which increase in the described area from west to east. Along a specific metadolerite, which can be traced approx. 40 km, the metamorphic grade changes from greenschist to amphibolite facies. In the western parts static conditions and in the eastern parts dynamic conditions, prevailed during the alteration. Sánerutian shear zones in the eastern parts depict the dynamic conditions found here.

scholarly journals Screening of Amazonian bacillus strains for lipase production using glycerol as substrate

ScientiaTec ◽  
2020 ◽  
Vol 7 (03) ◽  
Author(s):  
Giandra Volpato ◽  
Victória Furtado Migliavacca ◽  
Bruna Coelho de Andrade ◽  
Júlio Xandro Heck ◽  
Marco Antônio Záchia Ayub
Keyword(s):  
Organic Synthesis ◽  
Culture Medium ◽  
Lipolytic Activity ◽  
Gum Arabic ◽  
Lipase Production ◽  
Culture Conditions ◽  
Search And Selection ◽  
Triton X ◽  
Potential Use ◽  
Selection Of

The industrial application of lipolytic enzymes has been studied mainly due to the ability of these enzymes in catalyze reactions of synthesis and their stability in various organic solvents. One possibility is the use of lipase the organic synthesis, taking advantage as the generation of waste and difficult recovery of sub bioproducts. In this work, we carried out a selection of eighty-four isolates of Bacillus amazonian for lipase production, of which 30 strains showed lipolytic activity. The study of the culture conditions was performed through a Plackett-Burman experimental design using the strain that presented the highest lipolytic activity in a culture medium using glycerol as substrate.  The studied conditions were: concentration of soybean oil, olive oil, triton X-100, gum arabic, glycerol, and (NH4)2SO4, pH, temperature and concentration of inoculums. The best result obtained were 27 U/L in 48 h of cultivation by Bacillus circulans BL53. This work shows that the search and selection of microorganism with lipolytic activities can facilitate the discovery of new lipases, with potential use as by-product surplus.

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