Influences of Metal Sprayed Coating Artificial Dental Root on the Vital Tissue

1998 ◽  
Author(s):  
M. Magome ◽  
K. Hara ◽  
K. Sano ◽  
Y. Ueda
Keyword(s):  
Plasma Spraying ◽  
Atmospheric Plasma Spraying ◽  
Aluminum Coating ◽  
The Other ◽  
Atmospheric Plasma ◽  
In Vitro Experiments ◽  
Wire Frame ◽  
Sprayed Coating

Abstract Artificial dental root material has been very important among all bio-materials. In this study, two different ways of aluminum coating are used. One is wire frame spraying, and the other is atmospheric plasma spraying. The affinity, stability, and connectivity of aluminum toxins with sprayed coating are used and the possibility for applying ways are examined. Acute toxic tests are performed clinically. Both in-vivo and in-vitro experiments are performed on a dog, and the results showed that aluminum sprayed coating is good as an artificial dental root material.

scholarly journals Induction of the Galactose Enzymes in Escherichia coli Is Independent of the C-1-Hydroxyl Optical Configuration of the Inducer d-Galactose

2008 ◽  
Vol 190 (24) ◽  
pp. 7932-7938 ◽  
Author(s):  
Sang Jun Lee ◽  
Dale E. A. Lewis ◽  
Sankar Adhya
Keyword(s):  
Escherichia Coli ◽  
Cell Wall ◽  
Carbon Source ◽  
The Other ◽  
Biosynthetic Pathways ◽  
In Vitro Experiments ◽  
Metabolizing Enzymes ◽  
Optical Configuration

ABSTRACT The two optical forms of aldohexose galactose differing at the C-1 position, α-d-galactose and β-d-galactose, are widespread in nature. The two anomers also occur in di- and polysaccharides, as well as in glycoconjugates. The anomeric form of d-galactose, when present in complex carbohydrates, e.g., cell wall, glycoproteins, and glycolipids, is specific. Their interconversion occurs as monomers and is effected by the enzyme mutarotase (aldose-1-epimerase). Mutarotase and other d-galactose-metabolizing enzymes are coded by genes that constitute an operon in Escherichia coli. The operon is repressed by the repressor GalR and induced by d-galactose. Since, depending on the carbon source during growth, the cell can make only one of the two anomers of d-galactose, the cell must also convert one anomer to the other for use in specific biosynthetic pathways. Thus, it is imperative that induction of the gal operon, specifically the mutarotase, be achievable by either anomer of d-galactose. Here we report in vivo and in vitro experiments showing that both α-d-galactose and β-d-galactose are capable of inducing transcription of the gal operon with equal efficiency and kinetics. Whereas all substitutions at the C-1 position in the α configuration inactivate the induction capacity of the sugar, the effect of substitutions in the β configuration varies depending upon the nature of the substitution; methyl and phenyl derivatives induce weakly, but the glucosyl derivative does not.

In vitro and in vivo effects of increased concentrations of free fatty acids on free thyroxin measurements as determined by five assays

1990 ◽  
Vol 36 (4) ◽  
pp. 611-613 ◽  
Author(s):  
R Sapin ◽  
J L Schlienger ◽  
F Grunenberger ◽  
F Gasser ◽  
J Chambron
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
The Other ◽  
In Vitro Experiments ◽  
Fat Emulsion ◽  
Before And After ◽  
High Concentrations ◽  
In Vivo Effects

Abstract To compare in vitro and in vivo effects of increased concentrations of free fatty acids (FFA) on free thyroxin (FT4) values, we measured FT4 in three pooled sera supplemented with oleate and in serum from 18 euthyroid patients before and after an infusion of fat emulsion (Intralipid). We used five FT4 RIA kits: two two-step methods [Gammacoat, Baxter (GC); Ria-gnost, Behring (RG)], two analog RIAs [Amerlex-M, Amersham (AM); Coat-Ria, BioMérieux (CR)], and one kit with labeled antibodies [Amerlex-MAB*, Amersham (AA)]. In vitro, at the maximum oleate addition of 5 mmol/L, FT4 increased when measured by the GC and RG kits, decreased by the AM kit, and showed no significant change by the CR and AA kits. In vivo, post-Intralipid, FFA concentrations rose significantly and the FT4 changes agreed with the results of the in vitro experiments, except for the RG kit, for which FT4 increased in only nine patients. We conclude that in vitro oleate addition is useful to predict the in vivo effect of increased FFA on FT4 values; moreover, in serum from euthyroid subjects with high concentrations of FFA, FT4 analyzed with the CR or AA kits should better agree with normal results for thyrotropin than FT4 values measured with the other kits.

scholarly journals GENERAL NONCHEMOTACTIC MUTANTS OF CAULOBACTER CRESCENTUS

Genetics ◽  
1986 ◽  
Vol 114 (3) ◽  
pp. 717-730
Author(s):  
Bert Ely ◽  
Connie J Gerardot ◽  
Donna L Fleming ◽  
Suely L Gomes ◽  
Peter Frederikse ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Gene Cluster ◽  
Caulobacter Crescentus ◽  
Chemotactic Response ◽  
The Other ◽  
In Vitro Experiments ◽  
Methyltransferase Activity ◽  
Chemotaxis Proteins

ABSTRACT We have examined 35 mutants that have defects in general chemotaxis. Genetic analysis of these mutants resulted in the identification of at least eight che genes located at six different positions on the Caulobacter crescentus chromosome. The cheR, cheB and cheT genes appeared to be located in a three-gene cluster. Mutations in these three genes resulted in the inability of the flagellum to reverse the direction of rotation. Defects in the cheR gene resulted in a loss of the ability to methylate the methyl-accepting chemotaxis proteins. In vitro experiments showed that the lack of in vivo methylation in cheR mutants was due to the absence of methyltransferase activity. Defects in the cheB gene resulted in greatly reduced chemotaxis-associated methylation in vivo and a loss of methylesterase activity in vitro. The specific defects responsible for the lack of a chemotactic response have not been determined for the other identified che genes.

scholarly journals Nanoindentation Study of Phase-pure Highly Crystalline Hydroxyapatite Coatings Deposited by Microplasma Spraying

2015 ◽  
Vol 9 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Arjun Dey ◽  
Anoop Kumar Mukhopadhyay
Keyword(s):  
Plasma Spraying ◽  
Cost Effective ◽  
Atmospheric Plasma ◽  
Present Contribution ◽  
Implant Surface ◽  
Hip Joint Replacement ◽  
Pmma Bone Cement ◽  
Spraying Method

The present contribution has originated from a critical biomedical engineering issue e.g., loosening of metallic prostheses fixed with poly(methylmethylacrylate) (PMMA) bone cement especially in the case of hip joint replacement which ultimately forces the patient to undergo a revision surgery. Subsequently surgeons invented a cementless fixation technology introducing a bioactive hydroxyapatite (HAp) coating to the metallic implant surface. A wide variety of different coating methods have been developed to make the HAp coating on metallic implants more reliable; of which ultimately the plasma spraying method has been commercially accepted. However, the story was not yet finished at all, as many questions were raised regarding coating adherence, stability and bio-functionality in bothin vitroandin vivoenvironments. Moreover, it has been now realized that the conventional high power plasma spraying (i.e. conventional atmospheric plasma spraying, CAPS) coating method creates many disadvantages in terms of phase impurity; reduced porosity limiting osseointegration and residual stresses which ultimately lead to inadequate mechanical properties and delamination of the coating. Further, poor crystallinity of HAp deposited by CAPS accelerates the rate of bioresorption, which may cause poor adhesion due to quick mass loss of HAp coatings. Therefore, in the present work a very recently developed method e.g., low power microplasma spraying method was utilized to coat HAp on SS316L substrates to minimize the aforementioned problems associated with commercial CAPS HAp coatings. Surgical grade SS316L has been chosen as the substrate material because it is more cost effective than Ti6Al4V and CoCrMo alloys.

Microstructural Study of Nanostructured ZrO2 Based Thermal Barrier Coatings Fabricated by High Efficiency Supersonic Plasma Spraying

2011 ◽  
Vol 189-193 ◽  
pp. 80-87 ◽  
Author(s):  
Yu Bai ◽  
Zhi Hai Han ◽  
Hong Qiang Li ◽  
Chao Xu ◽  
Yan Li Xu ◽  
...  
Keyword(s):  
Plasma Spraying ◽  
Bonding Strength ◽  
High Efficiency ◽  
Bimodal Distribution ◽  
Atmospheric Plasma Spraying ◽  
Atmospheric Plasma ◽  
Line System ◽  
Supersonic Plasma ◽  
Ysz Coating ◽  
Sprayed Coating

In this paper, the microstructure of nanostructured zirconia (ZrO2) based coating fabricated by newly developed process, high efficiency supersonic atmospheric plasma spraying (SAPS), is studied. The velocity and surface temperature of in-flight particles during spraying were monitored by on-line system and the microstructure and phase composition of the as-sprayed coating was characterized with SEM, TEM and XRD. Meanwhile, the bonding strength between the top coating and bond coating was measured. The results showed the average in-flight velocity of YSZ particles in SAPS was about 430m/s, which was much higher than that of conventional atmospheric plasma spraying (APS). The as-sprayed coating was composed of well-adhered fine lamellar structures with thickness of 1-4μm. The desirable structure was attributed to higher impact velocity of in-flight particles during SAPS process, resulting in the improvement of flattening degree of molten particles. Meanwhile, the SAPS-YSZ coating exhibited a bimodal distribution with small grains (30-50nm) and large grains (60-110nm), the latter was the main microstructure of the coating. In addition, it was found that the monoclinic zirconia existing in the original powders transformed into tetragonal phase after plasma spraying and the bonding strength of as-sprayed coating was as high as 46±3MPa. The high efficiency supersonic plasma spray, which offers some unique advantages over the conventional plasma spraying process, is expected to be potentially used to deposit a wide variety of nanostructured coatings at lower cost.

scholarly journals Nucleus-associated phosphorylation of Ins(1,4,5)P3 to InsP6 in Dictyostelium

1995 ◽  
Vol 312 (3) ◽  
pp. 911-917 ◽  
Author(s):  
J Van der Kaay ◽  
J Wesseling ◽  
P J M Van Haastert
Keyword(s):  
Hplc Analysis ◽  
The Other ◽  
In Vitro Experiments ◽  
Specific Sequence ◽  
Metabolic Route ◽  
And Function ◽  
Mutant Cells ◽  
Potential Substrate

Although many cells contain large amounts of InsP6, its metabolism and function is still largely unknown. In Dictyostelium lysates, the formation of InsP6 by sequential phosphorylation of inositol via Ins(3,4,6)P3 has been described [Stevens and Irvine (1990) Nature (London) 346, 580-583]; the second messenger Ins(1,4,5)P3 was excluded as a potential substrate or intermediate for InsP6 formation. However, we observed that mutant cells labelled in vivo with [3H]inositol showed altered labelling of both [3H]Ins(1,4,5)P3 and [3H]InsP6. In this report we demonstrate that Ins(1,4,5)P3 is converted into InsP6 in vitro by nucleus-associated enzymes, in addition to the previously described stepwise phosphorylation of inositol to InsP6 that occurs in the cytosol. HPLC analysis indicates that Ins(1,4,5)P3 is converted into InsP6 via sequential phosphorylation at the 3-, 6- and 2-positions. Ins[32P]P6, isolated from cells briefly labelled with [32P]Pi, was analysed using Paramecium phytase, which removes the phosphates of InsP6 in a specific sequence. The 6-position contained significantly more 32P radioactivity than the 4- or 5-positions, indicating that the 6-position is phosphorylated after the other two positions. The results from these in vivo and in vitro experiments demonstrate a metabolic route involving the phosphorylation of Ins(1,4,5)P3 via Ins(1,3,4,5)P4 and Ins(1,3,4,5,6)P5 to InsP6 in a nucleus-associated fraction of Dictyostelium cells.

scholarly journals In vitro study of bioactive glass coatings obtained by atmospheric plasma spraying

2020 ◽  
Author(s):  
Eugeni Cañas ◽  
Alina Grünewald ◽  
Rainer Detsch ◽  
María José Orts ◽  
Enrique Sánchez ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Plasma Spraying ◽  
In Vitro Study ◽  
Atmospheric Plasma Spraying ◽  
Vitro Study ◽  
Atmospheric Plasma
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