scholarly journals The Capacity of Periodontal Gel to Occupy the Spaces Inside the Periodontal Pockets Using Computational Fluid Dynamic

2019 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Luca Levrini ◽  
Luigi Paracchini ◽  
Maria Giulia Nosotti
Keyword(s):  
Rheological Properties ◽  
Computational Fluid Dynamic ◽  
Type I Collagen ◽  
Saline Solution ◽  
Fluid Dynamic ◽  
The Other ◽  
Periodontal Pocket ◽  
Type I ◽  
Cat Scan ◽  
Different Types

The aim of the current work is to demonstrate the capacity of a new periodontal gel to occupy the spaces inside the periodontal pockets through Computational Fluid Dynamic (CFD). The test gel consists of two resorbable medical grade polymers (PEO, Poly Ethylen Oxide and HPMC, Hydroxy Propyl Metyl Cellulose), Type I Collagen, SAP (Vitamin C), and PBS (Saline Solution), while the control gel is 14% doxyclin controlled release gel, which is used for treating periodontal pockets with probing ≥5 mm after scaling and root plaining. The study examined the fluid dynamic analysis (Computational Fluid Dynamic—CFD) of two different gels, used in dentistry to treat periodontitis, in relation to both the geometry of the periodontal pocket and the function of two different types of needles that are used to distribute the preparation. The periodontal pocket was determined by reading DICOM images taken from the patient’s CAT scan. The results show that the H42® gel comes out uniformly compared to the other gel. Moreover, it is possible to observe how the rheological properties of the gel allow the fluid to spread evenly within the periodontal pocket in relation to the geometry of the needle. In particular, H42® gel exits in a constant way both from the first and the second exit. In fact, it was observed that by changing the geometry of the needle or the type of periodontal gel, the distribution of the gel inside the pocket was no longer homogeneous. Thus, having the correct rheological properties and correct needle geometries both speeds up the gel and optimizes the pressure distribution. Currently, the literature is still lacking, therefore further studies will be needed to confirm these results.

Type I Collagen Biosynthesis by Skin Fibroblasts from Patients with Idiopathic Juvenile Osteoporosis

1995 ◽  
Vol 89 (1) ◽  
pp. 69-73 ◽  
Author(s):  
Andrew E. Pocock ◽  
Martin J. O. Francis ◽  
Roger Smith
Keyword(s):  
Osteogenesis Imperfecta ◽  
Type I Collagen ◽  
The Other ◽  
Type I ◽  
Osteogenesis Imperfecta Type ◽  
Unrelated Control ◽  
Type Iii ◽  
Collagen Peptides ◽  
Idiopathic Juvenile Osteoporosis ◽  
Osteogenesis Imperfecta Type I

1. Skin fibroblast lines were cultured from nine patients who had the features of idiopathic juvenile osteoporosis, six relatives, five unrelated control subjects and three unrelated patients with osteogenesis imperfecta type I. Some patients with idiopathic juvenile osteoporosis were adults whose previous osteoporosis was in remission. Two patients with idiopathic juvenile osteoporosis were siblings and one patient with idiopathic juvenile osteoporosis had a daughter with severe osteogenesis imperfecta (type III). 2. The ratio of type III to type I collagen, synthesized by fibroblasts, was increased in two of the patients with osteogenesis imperfecta type I and in the daughter with osteogenesis imperfecta type III, but was normal in all the other patients with idiopathic juvenile osteoporosis and the other relatives. 3. Radiolabelled collagen was digested by cyanogen bromide and separated on SDS-PAGE. Unreduced collagen peptides migrated normally, except those from both the two siblings with idiopathic juvenile osteoporosis. In these two lines, abnormal migration suggested the presence of collagen I mutations. 4. The secretion of synthesized collagen by these two idiopathic juvenile osteoporosis lines and two others was reduced to only 43–45% as compared with a line from a 13-year-old control subject, which was defined as 100%. The three osteogenesis imperfecta type I lines secreted 18–37%, the other five idiopathic juvenile osteoporosis lines secreted 57–75%, the relatives (including the daughter with severe osteogenesis imperfecta) secreted 49–115% and the controls secreted 69–102%. 5. We conclude that qualitative abnormalities of type I collagen associated with a reduction in total secreted collagen synthesis may occur in a minority of patients with idiopathic juvenile osteoporosis; these patients could represent a subset of patients with this disorder.

Comparative Analysis of the Proteomic Profile of Cattle Hides that Produce Loose and Tight Leather using In-Gel Tryptic Digestion followed by LC-MS/MS

2020 ◽  
Vol 115 (11) ◽  
pp. 399-408
Author(s):  
Catherine Maidment ◽  
Meekyung Ahn ◽  
Rafea Naffa ◽  
Trevor Loo ◽  
Gillian Norris
Keyword(s):  
Type I Collagen ◽  
Raw Material ◽  
Type I ◽  
Collagen Structure ◽  
Proteomic Profile ◽  
Collagen Network ◽  
Collagen Concentration ◽  
Different Types ◽  
Molecular Components ◽  
First Time

Looseness is a defect found in leather that reduces its quality by causing a wrinkly appearance in the finished product, resulting in a reduction in its value. Earlier studies on loose leather using microscopy and Raman spectroscopy reported a change in the collagen structure of loose leather. In this study, proteomics was used to investigate the possible molecular causes of looseness in the raw material, the first time such a study has been carried out. Proteins extracted from two regions of raw hide using two different methods were analysed; those taken from the distal axilla, an area prone to looseness, and those taken from the backbone which is less prone to looseness. Analyses using 1DE-LC-MS/MS showed that although the overall collagen concentration was similar in both areas of the hide, the distribution of the different types of collagen differed.  Specifically, concentrations of type I collagen, and the collagen-associated proteoglycan decorin were lower in samples taken from the distal axilla, symptomatic of a collagen network with excess space seen for these samples using confocal microscopy. This study suggests a possible link between the molecular components of raw cattle hide and looseness and more importantly between the molecular components of skin and skin defects. There is therefore potential to develop biomarkers for looseness which will enable early preventative action.

Pharmacological inhibitors to identify roles of cathepsin K in cell-based studies: a comparison of available tools

2009 ◽  
Vol 390 (9) ◽  
Author(s):  
Sylvie Desmarais ◽  
Frédéric Massé ◽  
M. David Percival
Keyword(s):  
Human Cell ◽  
Type I Collagen ◽  
Cathepsin K ◽  
The Other ◽  
Enzyme Assays ◽  
Type I ◽  
Treatment Of Osteoporosis ◽  
Cysteine Cathepsins ◽  
Rodent Cell ◽  
Enzyme Selectivity

Abstract Cathepsin K (Cat K) degrades bone type I collagen and is a target for the pharmacological treatment of osteoporosis. Further roles for Cat K have been recently described, some of which are supported by the use of purportedly selective Cat K inhibitors in human and rodent cell-based assays. Twelve commercial and non-commercial Cat K inhibitors were profiled against a panel of purified human, rat, and mouse cysteine cathepsins and in two cell-based enzyme occupancy assays for activity against Cat K, B, and L. Ten inhibitors, including the carbohydrazide Cat K inhibitor II (Boc-Phe-Leu-NHNH-CO-NHNH-Leu-Z), the non-covalent K4b, and the epoxide NC-2300, have either little Cat K selectivity, or appear poorly cell penetrant. The amino-acetonitrile-containing inhibitors L-873724 and odanacatib show greater than 100-fold human Cat K enzyme selectivity and have similar IC50 values against each cathepsin in cell-based and enzyme assays. The basic inhibitor balicatib has greater cellular potencies than expected on the basis of purified enzyme assays. The accumulation of [14C]-balicatib in fibroblasts is blocked by prior treatment of the cells with NH4Cl, consistent with balicatib having lysosomotropic properties. These results support the use of L-873724 and odanacatib as tools to identify novel roles for Cat K using human cell-based systems, but suggest using caution in the interpretation of studies employing the other compounds.

Mechanical Stress-Induced Orientation and Ultrastructural Change of Smooth Muscle Cells Cultured in Three-Dimensional Collagen Lattices

1994 ◽  
Vol 3 (6) ◽  
pp. 481-492 ◽  
Author(s):  
Keiichi Kanda ◽  
Takehisa Matsuda
Keyword(s):  
Smooth Muscle ◽  
Tensile Stress ◽  
Smooth Muscle Cells ◽  
Type I Collagen ◽  
Dynamic Stress ◽  
Three Dimensional ◽  
Muscle Cells ◽  
The Other ◽  
Type I ◽  
Oriented Parallel

The effect of tensile stress on the orientation and phenotype of arterial smooth muscle cells (SMCs) cultured in three-dimensional (3D) type I collagen gels was morphologically investigated. Ring-shaped hybrid tissues were prepared by thermal gelation of a cold mixed solution of type I collagen and SMCs derived from bovine aorta. The tissues were subjected to three different modes of tensile stress. They were floated (isotonic control), stretched isometrically (static stress) and periodically stretched and recoiled by 5% above and below the resting tissue length at 60 RPM frequency (dynamic stress). After incubation for up to four wk, the tissues were investigated under a light microscope (LM) and a transmission electron microscope (TEM). Hematoxylin and eosinstained LM samples revealed that, irrespective of static or dynamic stress loading, SMCs in stress-loaded tissues exhibited elongated bipolar spindle shape and were regularly oriented parallel to the direction of the strain, whereas those in isotonic control tissues were polygonal or spherical and had no preferential orientation. In Azan-stained samples, collagen fiber bundles in isotonic control tissues were somewhat retracted around the polygonal SMCs to form a random network. On the other hand, those in statically and dynamically stressed tissues were accumulated and prominently oriented parallel to the stretch direction. Ultrastructural investigation using a TEM showed that SMCs in control and statically stressed tissues were almost totally filled with synthetic organelles such as rough endoplasmic reticulums, free ribosomes, Golgi complexes and mitochondria, indicating that the cells remained in the synthetic phenotype. On the other hand, SMCs in dynamically stressed tissues had increased fractions of contractile apparatus, such as myofilaments, dense bodies and extracellular filamentous materials equivalent to basement membranes, that progressed with incubation time. These results indicate that periodic stretch, in concert with 3-D extracellular collagen matrices, play a significant role in the phenotypic modulation of SMCs from the synthetic to the contractile state, as well as cellular and biomolecular orientation.

scholarly journals Abnormal type I collagen metabolism by cultured fibroblasts in lethal perinatal osteogenesis imperfecta

1984 ◽  
Vol 217 (1) ◽  
pp. 103-115 ◽  
Author(s):  
J F Bateman ◽  
T Mascara ◽  
D Chan ◽  
W G Cole
Keyword(s):  
Osteogenesis Imperfecta ◽  
Cell Lines ◽  
Type I Collagen ◽  
The Other ◽  
Collagen Metabolism ◽  
Structural Defects ◽  
Collagen Molecule ◽  
Type I ◽  
Cultured Fibroblasts ◽  
Post Translational Modifications

Cultured skin fibroblasts from seven consecutive cases of lethal perinatal osteogenesis imperfecta (OI) expressed defects of type I collagen metabolism. The secretion of [14C]proline-labelled collagen by the OI cells was specifically reduced (51-79% of control), and collagen degradation was increased to twice that of control cells in five cases and increased by approx. 30% in the other two cases. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis revealed that four of the OI cell lines produced two forms of type I collagen consisting of both normally and slowly migrating forms of the alpha 1(I)- and alpha 2(I)-chains. In the other three OI cell lines only the ‘slow’ alpha (I)′- and alpha 2(I)′-chains were detected. In both groups inhibition of the post-translational modifications of proline and lysine resulted in the production of a single species of type I collagen with normal electrophoretic migration. Proline hydroxylation was normal, but the hydroxylysine contents of alpha 1(I)′- and alpha 2(I)′-chains purified by h.p.l.c. were greater than in control alpha-chains. The glucosylgalactosylhydroxylysine content was increased approx. 3-fold while the galactosylhydroxylysine content was only slightly increased in the alpha 1(I)′-chains relative to control alpha 1(I)-chains. Peptide mapping of the CNBr-cleavage peptides provided evidence that the increased post-translational modifications were distributed throughout the alpha 1(I)′- and alpha 2(I)′-chains. It is postulated that the greater modification of these chains was due to structural defects of the alpha-chains leading to delayed helix formation. The abnormal charge heterogeneity observed in the alpha 1 CB8 peptide of one patient may reflect such a structural defect in the type I collagen molecule.

Improved Prediction of Indoor Contaminant Distribution for Entire Buildings

2002 ◽  
Author(s):  
Jinchao Yuan ◽  
Jelena Srebric
Keyword(s):  
Computational Fluid Dynamic ◽  
Fluid Dynamic ◽  
The Other ◽  
Zone Model ◽  
Cfd Model ◽  
Combined Model ◽  
Contaminant Distribution

This paper presents a study on improvements of multi-zone models for predicting building contaminant distribution by combining a multi-zone model with a Computational Fluid Dynamic (CFD) model. The motivation is to avoid the long computations in the CFD model that are required for predicting concentrations in entire buildings. Two cases are investigated using the combined model and the results are compared to reliable experimental or CFD data. The comparisons show that the combined model provides better results than the multi-zone model alone in one of the cases, while in the other no major improvements were observed. Further investigation and development of the combined model is needed.

Influence of Mechanical Load on the Degradation of Corneal Collagen

2008 ◽  
Author(s):  
Ramin Zareian ◽  
Kelli P. Church ◽  
Jeffrey W. Ruberti
Keyword(s):  
Self Assembly ◽  
Type I Collagen ◽  
Mechanical Load ◽  
Structural Performance ◽  
Type I ◽  
Connective Tissues ◽  
Bacterial Collagenase ◽  
Collagen Triple Helix ◽  
Different Types ◽  
Corneal Collagen

Collagen is one of the most important structural proteins in vertebrate animals. Over 25 different types of collagen have been identified, but type I collagen is the most abundant fibril forming collagen and contributes to the structural performance numerous connective tissues including ligaments, tendons and cornea [1]. In addition to collagen self-assembly, collagen degradation is an important step in the development, remodeling, homeostasis and pathology of load-bearing ECM. Matrix Metalloproteinase (MMP) types I and VIII, bacterial collagenase and cathepsin are the best known enzymes capable of directly degrading the collagen triple helix [2, 3]. Several researchers have hypothesized that straining collagen fibrils makes them less susceptible to enzymatic degradation [4, 5]. This concept, which we refer to as “strain-stabilization” has important implications for our understanding of collagen as an engineering material.

THE STRUCTURE OF PLATELET-REACTIVE SITES IN COLLAGENS

1987 ◽  
Author(s):  
M J Barnes ◽  
C M Fitzsimmons ◽  
L F Morton
Keyword(s):  
Platelet Aggregation ◽  
Type I Collagen ◽  
Quaternary Structure ◽  
The Other ◽  
Type I ◽  
Amino Acid Residues ◽  
Reactive Site ◽  
Parent Molecule ◽  
Type Iii ◽  
Helical Configuration

Collagen-induced platelet aggregation is an essential step in haemostasis and may be important in thrombosis, particularly that associated with the atherosclerotic plaque. We have located platelet-binding sites in collagen by fragmentation of the molecule with cyanogen bromide (CB) and measurement of the platelet aggregatory activity of the fragments following their renaturation to restore triple-helical configuration and polymerisation to introduce quaternary structure. We have found a high1y-reactive site in collagen type III located in the peptide α1(III)CB4 which was active at a concentration of less than 0.5μg/ml. The equivalent peptide from type I collagen α1(I)CB3 occurring in precisely the same location in the respective parent molecule (residues 403-551) and exhibiting a structure highly homologous to that of α1(III)CB4 was active only at concentrations higher than 200μg/ml. α1(I)CB7, the most active of the type I peptides, was able to cause platelet aggregation at around 5μg/ml whilst the equivalent type III peptide μ1(III)CB5 was inactive. Modification of specific amino acid residues indicated the importance of lysine in the activity of μ1(III)CB4 and of arginine in that of α1(I)CB7. Comparison of the structure of these peptides leads us to conclude that a reactive site comprises two basic residues, a specific distance apart, the conformation of one to the other dictated by collagen triple-helical configuration. One residue occurs in the sequence GlyPro(orHyp)LYS(orARG)GlyGlu, the other in GlyLYS(orARG)Pro(orHyp)GlyGlu. The lower reactivity of α1(I)CB7 relative to α1(III)CB4 can be attributed to the presence of two arginyl rather than lysyl residues and because the spacing of the two in CB4(G1y-LYS-Y-G1y-X-Y-G1y-X-LYS) represents a more favourable one than in CB7(Gly-X-ARG-Gly-X-Y-Gly-X-Y-Gly-ARG-Y).

scholarly journals Valve Geometry and Flow Optimization through an Automated DOE Approach

Fluids ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 17 ◽  
Author(s):  
Micaela Olivetti ◽  
Federico Giulio Monterosso ◽  
Gianluca Marinaro ◽  
Emma Frosina ◽  
Pietro Mazzei
Keyword(s):  
Design Of Experiments ◽  
Computational Fluid Dynamic ◽  
Fluid Dynamic ◽  
The Other ◽  
Standard Approach ◽  
Optimization Approach ◽  
Flow Optimization ◽  
Time To Market ◽  
Other Hand

The objective of this paper is to show how a completely virtual optimization approach is useful to design new geometries in order to improve the performance of industrial components, like valves. The standard approach for optimization of an industrial component, as a valve, is mainly performed with trials and errors and is based on the experience and knowledge of the engineer involved in the study. Unfortunately, this approach is time consuming and often not affordable for the industrial time-to-market. The introduction of computational fluid dynamic (CFD) tools significantly helped reducing time to market; on the other hand, the process to identify the best configuration still depends on the personal sensitivity of the engineer. Here a more general, faster and reliable approach is described, which uses a CFD code directly linked to an optimization tool. CAESES® associated with SimericsMP+® allows us to easily study many different geometrical variants and work out a design of experiments (DOE) sequence that gives evidence of the most impactful aspects of a design. Moreover, the result can be further optimized to obtain the best possible solution in terms of the constraints defined.

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