Surface Changes of Fluoride-Releasing Composites: a Comparison of in Vivo and in Vitro Results

1995 ◽  
Vol 9 (4) ◽  
pp. 348-354 ◽  
Author(s):  
G.E.H.M. Dijkman ◽  
J. De Vries ◽  
W.L. Jongebloed ◽  
J. Arends
Keyword(s):  
Mechanical Properties ◽  
Outer Surface ◽  
Tap Water ◽  
Surface Microhardness ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Over Time ◽  
Surface Changes

Fluoride-releasing composites lose fluoride very slowly over time. An interesting question is the possible change in mechanical properties related to the F release. If this happens, it might be expected that the mechanical properties of the outer surface of a fluoridating composite are affected first. The purpose of this study was to investigate in vivo and in vitro the changes in surface microhardness and surface structure of three fluoride-releasing composites and a non-F-containing control after 28 days. In the in vitro experiment, the composites were stored in tap water at 37°C. The results show that all composites stored in water were significantly softened after 28 days. In vivo, however, a very different picture emerged: The surface microhardness of the fluoride-releasing composites did not change significantly. In vitro, the data indicate that the amount of softening of the fluoridating composites is related to the amount of fluoride released. No relation was found between the amount of F released in one month in vitro and the microhardness changes in vivo. SEM micrographs of fluoridating composites do not reflect the microhardness changes mentioned.

In Vitro Experimental Investigation of the Integrity of the Stem–Cement Interface

2013 ◽  
Vol 647 ◽  
pp. 53-56
Author(s):  
Hong Yu Zhang ◽  
Leigh Fleming ◽  
Liam Blunt
Keyword(s):  
Experimental Investigation ◽  
Fluid Flow ◽  
Hip Replacement ◽  
Hip Prosthesis ◽  
Vitro Experiment ◽  
Cement Interface ◽  
In Vitro Experiment ◽  
Mechanical Bonding

The rationale behind failure of cemented total hip replacement is still far from being well understood in a mechanical and molecular perspective. In the present study, the integrity of the stem–cement interface was investigated through an in vitro experiment monitoring fluid flow along this interface. The results indicated that a good mechanical bonding formed at the stem–cement interface before debonding of this interface was induced by physiological loadings during the in vivo service of the hip prosthesis.

Cadmium Chloride Induces Memory Deficits and Hippocampal Damage by Activating the JNK/p66Shc/NADPH Oxidase Axis

2020 ◽  
Vol 39 (5) ◽  
pp. 477-490
Author(s):  
Attalla Farag El-kott ◽  
Ali S. Alshehri ◽  
Heba S. Khalifa ◽  
Abd-El-karim M. Abd-Lateif ◽  
Mohammad Ali Alshehri ◽  
...  
Keyword(s):  
Nadph Oxidase ◽  
Cadmium Chloride ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Male Rats ◽  
Hippocampal Damage ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
In Vivo Experiment

This study investigated whether the mechanism underlying the neurotoxic effects of cadmium chloride (CdCl2) in rats involves p66Shc. This study comprised an initial in vivo experiment followed by an in vitro experiment. For the in vivo experiment, male rats were orally administered saline (vehicle) or CdCl2 (0.05 mg/kg) for 30 days. Thereafter, spatial and retention memory of rats were tested and their hippocampi were used for biochemical and molecular analyses. For the in vitro experiment, control or p66Shc-deficient hippocampal cells were treated with CdCl2 (25 µM) in the presence or absence of SP600125, a c-Jun N-terminal kinase (JNK) inhibitor. Cadmium chloride impaired the spatial learning and retention memory of rats; depleted levels of glutathione and manganese superoxide dismutase; increased reactive oxygen species (ROS), tumor necrosis factor α, and interleukin 6; and induced nuclear factor kappa B activation. Cadmium chloride also decreased the number of pyramidal cells in the CA1 region and induced severe damage to the mitochondria and endoplasmic reticulum of cells in the hippocampi of rats. Moreover, CdCl2 increased the total unphosphorylated p66Shc, phosphorylated (Ser36) p66Shc, phosphorylated JNK, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, cytochrome c, and cleaved caspase-3. A dose–response increase in cell death, ROS, DNA damage, p66Shc, and NADPH oxidase was also observed in cultured hippocampal cells treated with CdCl2. Of note, all of these biochemical changes were attenuated by silencing p66Shc or inhibiting JNK with SP600125. In conclusion, CdCl2 induces hippocampal ROS generation and apoptosis by promoting the JNK-mediated activation of p66Shc.

scholarly journals Alternative control of post-harvest diseases in Tainung 1 papaya

2018 ◽  
Vol 48 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Andréa Mirne de Macêdo Dantas ◽  
Selma Rogéria de Carvalho Nascimento ◽  
Beatriz Letícia Silva da Cruz ◽  
Fernando Henrique Alves da Silva ◽  
Márcia Michelle de Queiroz Ambrósio ◽  
...  
Keyword(s):  
Essential Oil ◽  
Mycelial Growth ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Post Harvest ◽  
Randomized Design ◽  
Clove Essential Oil

ABSTRACT Controlling post-harvest papaya diseases without using agrochemicals is a challenge for producers. This study aimed at evaluating the effect of clove essential oil, biological fungicide (Trichodermil®), resistance inducer (Cob Sistem®) and chemical fungicide (Imazacure®) on the in vitro control of phytopathogenic fungi isolates from papaya as well as on the post-harvest quality of Tainung 1 papaya. The in vitro experiment was conducted in a complete randomized design, with five fungal species x five treatments and five replications. The in vivo experiment was conducted in a complete randomized design, with five treatments x five storage times, five replications and three fruits per replication. The fruits were stored under refrigeration at 10 ± 2 ºC and 90 ± 5 % of relative humidity and evaluated at 0, 7, 14, 21 and 28 days of storage, plus two shelf life days at 25 ± 2 ºC, to simulate marketing conditions. The inhibition of mycelial growth was evaluated in the in vitro experiment, while the diseases occurrence and post-harvest quality of the fruits were evaluated in the in vivo experiment. The clove essential oil and Trichodermil® were as efficient as Imazacure® in inhibiting the mycelial growth of Alternaria sp., Colletotrichum gloeosporioides and Rhizopus sp. The treatments with clove essential oil, Trichodermil® and Imazacure® were similar in controlling the pathogens up to 21 days of storage. The treatments had no effect on the fruits soluble solid contents.

scholarly journals Study the effect of the mixture of alcoholic extract of Peganum harmala seeds & Pericarp of Punica granutum on viability of protoscolices of Echinococcus granulosus in vitro and in vivo

2013 ◽  
Vol 7 (2) ◽  
pp. 39-46
Author(s):  
Fawzia Ahmed AL-Shanawi ◽  
Noor Nihad Baker
Keyword(s):  
Echinococcus Granulosus ◽  
Infected Group ◽  
Alcoholic Extract ◽  
Peganum Harmala ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Complete Inactivation

This study included the preparation of the mixture of alcoholic extracts of Peganum harmala seeds and Pericarp of Punica granutum at concentration (1+40), (1.5+45), (2+50) mgml. To study the influence of the mixture of alcoholic extracts of P. harmala and P. granutum on viability of the protoscolices of Echinococcus granulosus In vitro (In tubes), and In vivo (In albaino white mice injected intraperitoneal with protoscolices). In vitro experiment revealed complete inactivation of protoscolices (death) with concentration (2+ 50) mg/ ml after 30 minute. In vivo a significant reduction in weight of liver and spleen occurred in treated groups in comparison to control (untreated) infected group.

scholarly journals Study of the deformation of sponge application hemostatic materials

2020 ◽  
Vol 7 (3) ◽  
pp. 21-32
Author(s):  
V. A. Lipatov ◽  
D. A. Severinov ◽  
M.D. Z. Naimzda ◽  
E. L. Puchkova
Keyword(s):  
Mechanical Properties ◽  
Residual Strain ◽  
Glass Substrate ◽  
Residual Deformation ◽  
Lower Surface ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Load Removal ◽  
The Difference

Purpose of the study. To evaluate the dynamics of deformation of spongy application hemostatic materials in an in vitro experiment. Materials and methods. As materials of the study the following samples of hemostatic materials were used: Tachocomb (No. 1), Gelita-Spon Standard (No. 2), Reggicel Fibrillar (No. 3), samples of hemostatic sponges developed jointly with Lintex (St.Petersburg, Russia) on the basis of sodium-Carboxymethyl Cellulose (No. 3): Samples were placed on a glass substrate which was mounted on the rising REM cross-arm 0.2–1 to estimate 50% compression residual strain. A glass substrate rigidly attached to the indenter was mounted so that its lower surface would touch the upper surface of the sample. The crossarm was then lifted at 30 mm/min, compressing the sample until the force reached 50 N, after which the sample was allowed to stand under pressure for 10 seconds. After the load was removed, the sample was removed from the substrate and the compression thickness measured (immediately after compression, after 5, 10 and 30 minutes). Results. The values of the compression residual deformation on the thickness 50% (immediately after the load removal) of the samples of group No. 1 differ statistically significantly from the values of groups No. 2 and No. 3 on 5.92 and 3.51, respectively. The difference between groups No. 1 and No. 4 is 5.61. The ODP values 50% 5 minutes after the load of Group No. 1 samples was removed differ from Groups No. 2 and No. 3 on 5.93 and 3.85, respectively. The difference between groups No. 1 and No. 4 is 6.57. After 30 minutes after compression, the values of the residual deformation of the samples of group No. 1 differ from those of groups No. 2 and No. 3 on 6.9 and 4.3. The difference between groups No. 1 and No. 4 is 6.9. Also, the values of the residual deformation of the samples of group No. 2 exceed the values of the samples of group No. 3 by 1.6 times, and in comparison with group No. 4 is less by 0.03. There are fewer statistical differences with other groups in pilot groups 5–7. Conclusion. The highest values of the indicator "residual deformation at compression by thickness 50%" are noted in group No. 7 (samples based on Na-CMC unpressurized) — 32.34, which causes high mechanical properties of jaws made from this material.

An In-Vitro Experiment to Study Sustained Torque on the Spine

2009 ◽  
Author(s):  
Robert Rizza ◽  
Xue-Cheng Liu ◽  
Mohammad Mahinfalah ◽  
Yu Wang ◽  
John Thometz ◽  
...  
Keyword(s):  
Shear Force ◽  
Bone Growth ◽  
Axial Loading ◽  
Spinal Curvature ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Immature Spine ◽  
Tension Loading

In adolescent scoliosis patients, as the vicious cycle hypothesis proposed by Dr. Stokes suggests [1], a lateral spinal curvature produces asymmetrical loading of the skeletally immature spine, which in turn causes asymmetrical growth and therefore progressive wedging deformity. Numerous studies have been done to evaluate the effect of sustained compression or tension loading on the spinal bone growth [2,3]. However, in scoliosis patients, there is not only the asymmetrical axial loading which will worsen the curve progression, but also constant shear force in the transverse plane that may affect the bone growth. So far, no in vivo experiment has been done to study the effect of shear force on the spine. The goal of this study is to design an in vitro experiment that will provide incessant torques in the calves’ tails, and determine the relationship between the magnitude of the torque and change of stress between tail segments.

Influence of Neuroleptics on Cytotoxic Activity of Rat Natural Killer Cells

1998 ◽  
Vol 11 (2) ◽  
pp. 57-62
Author(s):  
A.J. Madej ◽  
J. Kowalski ◽  
D. Belowski ◽  
Z. S. Herman
Keyword(s):  
Cytotoxic Activity ◽  
Nk Cells ◽  
Nk Cell ◽  
Cell Activity ◽  
Nk Cell Activity ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
In Vivo Experiment

The aim of the study was to evaluate the in vivo and in vitro effects of three neuroleptics (chlorpromazine, haloperidol, and sulpiride) on the activity of rat spleen NK cells. In the in vivo experiment, rats were injected with different intraperitoneal doses of neuroleptics given once, for 14 or 28 days. In the in vitro experiment rat spleen NK cells were cultured in medium containing two different concentrations of neuroleptics for three days. The cytotoxic activity of NK cells was evaluated by measuring 51Cr release from YAC-1 target cells after 4-hour incubation. We also measured, using fluorescein-labelled anti-NK monoclonal antibody, the percentage of NK cells in the splenocyte population before and after single intraperitoneal injections of neuroleptics. In the in vitro experiment, both haloperidol (1×10−5 M and 1×10−6 M) and sulpiride (1.5×10−3 M and 1.5×10−4 M) induced a statistically significant decrease in the cytotoxic activity of NK cells. The lower dose of chlorpromazine (6×10−6 M) decreased the cytotoxic activity of NK cells, while the higher dose (6×10−5 M) did not. In the in vivo experiment, both single and repeated doses of chlorpromazine (2 mg /kg /day), haloperidol (0.5 mg/kg/day) and sulpiride (50 mg/kg/day) increased NK cell activity. That effect reflected an increase in NK cell activity but not in the number of NK cells. The study has shown that the immunomodulatory effect of neuroleptics on NK cell activity depends mainly on drug concentrations and experimental conditions.

scholarly journals Influence of Different Strategies of Volume Replacement on the Activity of Matrix Metalloproteinases

2007 ◽  
Vol 106 (1) ◽  
pp. 85-91 ◽  
Author(s):  
Carlo A. Volta ◽  
Valentina Alvisi ◽  
Matilde Campi ◽  
Elisabetta Marangoni ◽  
Raffaele Alvisi ◽  
...  
Keyword(s):  
Hydroxyethyl Starch ◽  
Plasma Levels ◽  
Tissue Inhibitor Of Metalloproteinases ◽  
Tissue Inhibitor ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
Ringer’S Solution ◽  
Lactated Ringer's Solution

Background Excessive production of matrix metalloproteinase 9 (MMP-9) is linked to tissue damage and anastomotic leakage after large bowel surgery. Hence, the aim of this study was to verify whether different strategies of fluids administration can reduce MMP-9 expression. Methods In the in vitro experiment, the authors tested the hypothesis of a direct inhibition of MMP-9 by the fluids used perioperatively, i.e., lactated Ringer's solution, 3.4% poligeline, and hydroxyethyl starch 130/0.4. In the in vivo experiment, 36 patients undergoing surgery for colon cancer were randomly assigned to three groups to receive lactated Ringer's solution, poligeline, or hydroxyethyl starch. MMP-9 and tissue inhibitor of metalloproteinases were measured from venous blood samples; the MMP-9/tissue inhibitor of metalloproteinases ratio was calculated as an index of equilibrium between the action of MMP-9 and its inhibition. Results In the in vitro experiment, the presence of hydroxyethyl starch 130/0.4 in the MMP-9 assay system showed a strong inhibition of the enzymatic activity compared with lactated Ringer's solution. In the in vivo experiment, MMP-9 and tissue inhibitor of metalloproteinases plasma levels did not differ among the three groups at baseline, whereas those levels increased significantly at the end of surgery. At that time, the MMP-9 plasma levels and the MMP-9/tissue inhibitor of metalloproteinases ratio were significantly higher in the lactated Ringer's solution and poligeline groups than in the hydroxyethyl starch group. These results were confirmed 72 h after surgery. Conclusions This study demonstrates that hydroxyethyl starch 130/04 decreases the circulating levels of MMP-9 in patients undergoing abdominal surgery.

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