The stability of impacted morsellized bone grafts in a metal cage under dynamic loaded conditions: an in vitro reconstruction of a segmental diaphyseal bone defect

Resonance frequency analysis (RFA) has been applied to detect the stability and boundary condition of the dental implant osseointegration in several investigations. Its clinical relating application was generally accepted. Nevertheless, these studies only presented the overall phenomena of osseointegration around the implant and were unable to diagnose the location of the bone defect. Therefore, the aim of this study refers to an effective detection technique for locating the position of bone defect surrounding the dental implant. Various in-vitro bone defect models composed of a dental implant, a healing abutment and an artificial bone block were used to perform the experimental modal analysis (EMA). The bone defect model was excited by an impacted hammer; induced vibration response was acquired by an accelerometer and processed through a spectrum analyzer. The statistical analysis was used to generalize the relationship between the obtained RF values and various bone defects from experimental results. The finding of this study indicates that RF decreases remarkably when the range and depth of defects increase. Thus, the direction of the defect is decided first by RF variations of the sound and defective side, and the position of the defect is discriminated later by RF differences of various bone defect models. This conclusion assists doctors in diagnosis after surgery.

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Resection of a Periosteal Osteosarcoma and Reconstruction Using the Ilizarov Technique of Segmental Transport

Journal of Hand Surgery (European Volume) ◽

10.1016/0266-7681(93)90092-t ◽

1993 ◽

Vol 18 (2) ◽

pp. 144-146 ◽

Cited By ~ 20

Author(s):

D. STOFFELEN ◽

J. LAMMENS ◽

G. FABRY

Keyword(s):

Internal Fixation ◽

Bone Defect ◽

Bone Grafts ◽

Tumour Resection ◽

Ilizarov Technique ◽

Diaphyseal Bone ◽

Segmental Transport ◽

Periosteal Osteosarcoma ◽

Autologous Bone ◽

Autologous Bone Grafts

The reconstruction of a large diaphyseal bone defect is a surgical challenge. Autologous bone grafts are usually insufficient to bridge the gap and allografts are prone to infection and may pose problems with internal fixation. Another solution is presented for the reconstruction of a large ulnar defect due to tumour resection, using the Ilizarov technique of segmental transport.

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Formation and Structure of Casein Micelles in Lactating Mammary Tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067741 ◽

1970 ◽

Vol 28 ◽

pp. 150-151

Author(s):

Robert J. Carroll ◽

Marvin P. Thompson ◽

Harold M. Farrell

Keyword(s):

Size Distribution ◽

G Protein ◽

Milk Proteins ◽

Mammary Tissue ◽

Colloidal System ◽

Casein Micelles ◽

The Stability

Milk is an unusually stable colloidal system; the stability of this system is due primarily to the formation of micelles by the major milk proteins, the caseins. Numerous models for the structure of casein micelles have been proposed; these models have been formulated on the basis of in vitro studies. Synthetic casein micelles (i.e., those formed by mixing the purified αsl- and k-caseins with Ca2+ in appropriate ratios) are dissimilar to those from freshly-drawn milks in (i) size distribution, (ii) ratio of Ca/P, and (iii) solvation (g. water/g. protein). Evidently, in vivo organization of the caseins into the micellar form occurs in-a manner which is not identical to the in vitro mode of formation.

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Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

Nuklearmedizin ◽

10.1055/s-0037-1620623 ◽

1977 ◽

Vol 16 (04) ◽

pp. 157-162 ◽

Cited By ~ 1

Author(s):

C. Schümichen ◽

B. Mackenbrock ◽

G. Hoffmann

Keyword(s):

Normal Saline ◽

Half Life ◽

Compound A ◽

Short Half Life ◽

Low Concentrations ◽

The Stability ◽

Kinetics Of ◽

In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

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Reverse torque values of abutment screws after dynamic loading: The effects of sealant agents and the taper of conical connections

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-19-00228 ◽

2020 ◽

Author(s):

Arda Ozdiler ◽

suleyman dayan ◽

Burc Gencel ◽

Gulbahar Isık-Ozkol

Keyword(s):

Dynamic Loading ◽

Antibacterial Agent ◽

In Vitro Study ◽

Control Group ◽

Silicone Sealant ◽

Reverse Torque ◽

The Stability ◽

Torque Values ◽

Chlorhexidine Gel

This in vitro study evaluated the influence of taper angles on the internal conical connections of implant systems and of the application of chlorhexidine gel as an antibacterial agent or a polyvinyl siloxane (PVS) sealant on the reverse torque values of abutment screws after dynamic loading. The current study tested four implant systems with different taper angles (5.4°, 12°, 45°, and 60°). Specimens were divided into three groups: control (neither chlorhexidine gel filled nor silicone sealed), 2% chlorhexidine gel-filled or silicone-sealed group, and group subjected to a dynamic load of 50 N at 1 Hz for 500,000 cycles prior to reverse torque measurements. Quantitative positive correlation was observed between the taper angle degree and the percentage of tightening torque loss. However, this correlation was significant only for the 60° connection groups except in the group in which a sealant was applied ( p = 0.013 for the control group, p = 0.007 for the chlorhexidine group). Percentages of decrease in the torque values of the specimens with silicone sealant application were significantly higher compared with both the control and chlorhexidine groups ( p = 0.001, p = 0.002, p = 0.001, and p = 0.002, respectively, according to the increasing taper angles); the percentage of decrease in torque values due to chlorhexidine application was statistically insignificant when compared with the control group. The application of gel-form chlorhexidine as an antibacterial agent does not significantly affect the stability of the implant–abutment connection under dynamic loads. PVS sealants may cause screw loosening under functional loads.

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Using FRET to Measure the Time it Takes for a Cell to Destroy a Virus

10.26434/chemrxiv.10299164.v1 ◽

2019 ◽

Author(s):

Candace E. Benjamin ◽

Zhuo Chen ◽

Olivia Brohlin ◽

Hamilton Lee ◽

Stefanie Boyd ◽

...

Keyword(s):

Cellular Uptake ◽

Rhodamine B ◽

Virus Like Particle ◽

A Cell ◽

Viral Nanoparticles ◽

The Stability ◽

Open Question ◽

Viral Surface ◽

Fret Pair

<div><div><div><p>The emergence of viral nanotechnology over the preceding two decades has created a number of intellectually captivating possible translational applications; however, the in vitro fate of the viral nanoparticles in cells remains an open question. Herein, we investigate the stability and lifetime of virus-like particle (VLP) Qβ - a representative and popular VLP for several applications - following cellular uptake. By exploiting the available functional handles on the viral surface, we have orthogonally installed the known FRET pair, FITC and Rhodamine B, to gain insight of the particle’s behavior in vitro. Based on these data, we believe VLPs undergo aggregation in addition to the anticipated proteolysis within a few hours of cellular uptake.</p></div></div></div>

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Applicability of Instability Index for In vitro Protein Stability Prediction

Protein and Peptide Letters ◽

10.2174/0929866526666190228144219 ◽

2019 ◽

Vol 26 (5) ◽

pp. 339-347 ◽

Cited By ~ 4

Author(s):

Dilani G. Gamage ◽

Ajith Gunaratne ◽

Gopal R. Periyannan ◽

Timothy G. Russell

Keyword(s):

Protein Stability ◽

Caulobacter Crescentus ◽

Effect Of Temperature ◽

Instability Index ◽

Dipeptide Composition ◽

Experimental Conditions ◽

The Stability ◽

Vitro Protein

Background: The dipeptide composition-based Instability Index (II) is one of the protein primary structure-dependent methods available for in vivo protein stability predictions. As per this method, proteins with II value below 40 are stable proteins. Intracellular protein stability principles guided the original development of the II method. However, the use of the II method for in vitro protein stability predictions raises questions about the validity of applying the II method under experimental conditions that are different from the in vivo setting. Objective: The aim of this study is to experimentally test the validity of the use of II as an in vitro protein stability predictor. Methods: A representative protein CCM (CCM - Caulobacter crescentus metalloprotein) that rapidly degrades under in vitro conditions was used to probe the dipeptide sequence-dependent degradation properties of CCM by generating CCM mutants to represent stable and unstable II values. A comparative degradation analysis was carried out under in vitro conditions using wildtype CCM, CCM mutants and two other candidate proteins: metallo-β-lactamase L1 and α -S1- casein representing stable, borderline stable/unstable, and unstable proteins as per the II predictions. The effect of temperature and a protein stabilizing agent on CCM degradation was also tested. Results: Data support the dipeptide composition-dependent protein stability/instability in wt-CCM and mutants as predicted by the II method under in vitro conditions. However, the II failed to accurately represent the stability of other tested proteins. Data indicate the influence of protein environmental factors on the autoproteolysis of proteins. Conclusion: Broader application of the II method for the prediction of protein stability under in vitro conditions is questionable as the stability of the protein may be dependent not only on the intrinsic nature of the protein but also on the conditions of the protein milieu.

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In Silico and in Vitro Evaluation of Deamidation Effects on the Stability of the Fusion Toxin DAB389IL-2

Current Proteomics ◽

10.2174/1570164616666190131150033 ◽

2019 ◽

Vol 16 (4) ◽

pp. 307-313 ◽

Cited By ~ 2

Author(s):

Nasrin Zarkar ◽

Mohammad Ali Nasiri Khalili ◽

Fathollah Ahmadpour ◽

Sirus Khodadadi ◽

Mehdi Zeinoddini

Keyword(s):

In Silico ◽

Catalytic Domain ◽

Md Simulations ◽

Special Importance ◽

Native Form ◽

Vitro Experiment ◽

In Vitro Experiment ◽

Pharmaceutical Protein ◽

The Stability

Background: DAB389IL-2 (Denileukin diftitox) as an immunotoxin is a targeted pharmaceutical protein and is the first immunotoxin approved by FDA. It is used for the treatment of various kinds of cancer such as CTCL lymphoma, melanoma, and Leukemia but among all of these, treatment of CTCL has special importance. DAB389IL-2 consists of two distinct parts; the catalytic domain of Diphtheria Toxin (DT) that genetically fused to the whole IL-2. Deamidation is the most important reaction for chemical instability of proteins occurs during manufacture and storage. Deamidation of asparagine residues occurs at a higher rate than glutamine residues. The structure of proteins, temperature and pH are the most important factors that influence the rate of deamidation. Methods: Since there is not any information about deamidation of DAB389IL-2, we studied in silico deamidation by Molecular Dynamic (MD) simulations using GROMACS software. The 3D model of fusion protein DAB389IL-2 was used as a template for deamidation. Then, the stability of deamidated and native form of the drug was calculated. Results: The results of MD simulations were showed that the deamidated form of DAB389IL-2 is more unstable than the normal form. Also, deamidation was carried by incubating DAB389IL-2, 0.3 mg/ml in ammonium hydrogen carbonate for 24 h at 37o C in order to in vitro experiment. Conclusion: The results of in vitro experiment were confirmed outcomes of in silico study. In silico and in vitro experiments were demonstrated that DAB389IL-2 is unstable in deamidated form.

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Role of the anconeus in the stability of a lateral ligament and common extensor origin–deficient elbow: an in vitro biomechanical study

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2018.11.040 ◽

2019 ◽

Vol 28 (5) ◽

pp. 974-981 ◽

Cited By ~ 1

Author(s):

Armin Badre ◽

David T. Axford ◽

Sara Banayan ◽

James A. Johnson ◽

Graham J.W. King

Keyword(s):

Biomechanical Study ◽

Lateral Ligament ◽

The Stability

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InsP7is a small-molecule regulator of NUDT3-mediated mRNA decapping and processing-body dynamics

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1922284117 ◽

2020 ◽

Vol 117 (32) ◽

pp. 19245-19253 ◽

Cited By ~ 1

Author(s):

Soumyadip Sahu ◽

Zhenzhen Wang ◽

Xinfu Jiao ◽

Chunfang Gu ◽

Nikolaus Jork ◽

...

Keyword(s):

Stress Responses ◽

Messenger Rna ◽

Control Process ◽

Stem Cell Differentiation ◽

Wild Type ◽

Inositol Pyrophosphate ◽

Body Dynamics ◽

Processing Body ◽

The Stability

Regulation of enzymatic 5′ decapping of messenger RNA (mRNA), which normally commits transcripts to their destruction, has the capacity to dynamically reshape the transcriptome. For example, protection from 5′ decapping promotes accumulation of mRNAs into processing (P) bodies—membraneless, biomolecular condensates. Such compartmentalization of mRNAs temporarily removes them from the translatable pool; these repressed transcripts are stabilized and stored until P-body dissolution permits transcript reentry into the cytosol. Here, we describe regulation of mRNA stability and P-body dynamics by the inositol pyrophosphate signaling molecule 5-InsP7(5-diphosphoinositol pentakisphosphate). First, we demonstrate 5-InsP7inhibits decapping by recombinant NUDT3 (Nudix [nucleoside diphosphate linked moiety X]-type hydrolase 3) in vitro. Next, in intact HEK293 and HCT116 cells, we monitored the stability of a cadre of NUDT3 mRNA substrates following CRISPR-Cas9 knockout ofPPIP5Ks(diphosphoinositol pentakisphosphate 5-kinases type 1 and 2, i.e.,PPIP5KKO), which elevates cellular 5-InsP7levels by two- to threefold (i.e., within the physiological rheostatic range). ThePPIP5KKO cells exhibited elevated levels of NUDT3 mRNA substrates and increased P-body abundance. Pharmacological and genetic attenuation of 5-InsP7synthesis in the KO background reverted both NUDT3 mRNA substrate levels and P-body counts to those of wild-type cells. Furthermore, liposomal delivery of a metabolically resistant 5-InsP7analog into wild-type cells elevated levels of NUDT3 mRNA substrates and raised P-body abundance. In the context that cellular 5-InsP7levels normally fluctuate in response to changes in the bioenergetic environment, regulation of mRNA structure by this inositol pyrophosphate represents an epitranscriptomic control process. The associated impact on P-body dynamics has relevance to regulation of stem cell differentiation, stress responses, and, potentially, amelioration of neurodegenerative diseases and aging.

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