A correlative in vitro study of osteoblast-like cells on titanium using SEM and TEM

1994 ◽  
Vol 52 ◽  
pp. 184-185
Author(s):  
K. E. Krizan ◽  
J. C. Keller ◽  
R. Zaharias ◽  
C. M. Stanford
Keyword(s):  
Uv Light ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Uranyl Acetate ◽  
Ruthenium Red ◽  
En Bloc ◽  
Sem And Tem ◽  
Biological Responses ◽  
Plastic Resin

The objective of this study was to evaluate cell morphology in response to an implant model surface using SEM and TEM. Through our efforts to understand these biological responses at the ultrastructure level we hope to better define surface characteristics that encourage optimal cell surface interaction. Osteoblast-like cells were derived from rat calvaria (RCOB), plated (5 X 104 cells/10 μl micromass) on cp Titanium (Ti) discs (7.5 X 3.5 mm) and grown twelve days in CMRL media +10% FSB, 5% /3-glycerophosphate, using 5% CO2 in air. Discs were prepared by polishing with 600 grit SiC paper, cleaned, washed, passivated and UV light sterilized. At 12 days, specimens for TEM were fixed with 3% formaldehyde/ glutaraldehyde, in 0.2M cacodylate buffer, pH 7.2 and post fixed in 1% Osmium, using 1 mg/ml Ruthenium Red. Cells were en bloc stained with 2% uranyl acetate, dehydrated and routinely embedded in Spurr plastic resin. These embedded cells were separated from their Ti discs using a cryofacture technique, reembedded and sectioned with diamond knife for TEM. Cells for SEM were fixed, post fixed, dehydrated, critical point dried and coated with Carbon.

Ultrastructure of E. coli: An in vitro study of cells cultured in the presence of four gastrointestinal (GI) hormones

1990 ◽  
Vol 48 (3) ◽  
pp. 628-629
Author(s):  
Leo J. Henz ◽  
Frank E. Johnson
Keyword(s):  
Morphological Changes ◽  
In Vitro Study ◽  
Uranyl Acetate ◽  
Culture Collection ◽  
En Bloc ◽  
Thin Sections ◽  
E Coli ◽  
Cacodylate Buffer ◽  
Synthetic Hormones

Hormones are found in exocrine secretions entering the gut. They alter the morphology of many eukaryotic cells; whether they affect the morphology of enteric flora is unknown. In this study, we examined the ultrastructure of E. coli, a common bacterium in the mammalian gut, for morphological changes resulting from exposure to GI hormones.E. coli (#11775 from American Type Culture Collection) were grown in protease-free trypticase soy broth (TSB) at 37°C for 18 hr to a concentration of 2 x 107 cells/ml. Pure synthetic hormones were used: sulfated C-terminal cholecystokinin octapeptide (CCK), pentagastrin (PG), cyclic somatostatin tetradecapeptide (SS), or the porcine form of secretin (SEC). These were individually added to. bacterial cultures in TSB to make 1 x 107 organisms/ml and 0.0, 0.5, 2.5, or 5.0 μg of hormone/ml, then incubated for 30 min at 37°C. The cultures were rapidly chilled and added to equal volumes of cold 6% glutaraldehyde in 0.2 M cacodylate buffer. After 30 min, the bacteria were concentrated by centrifugation (15 min at 4000 RPM) and the pellets suspended in cold 3% glutaraldehyde for an additional 15 min, followed by centrifugation. The pellets were resuspended in cold cacodylate buffer and stored at 2°C for 1-7 d. The cells were again centrifuged and the pellets were blotted with a strip of filter paper to remove excess fluid, then mixed with a drop of warm 2% agar. The agar suspensions were pipetted into cold saline. The resulting solidified extrusions were cut by hand into 2 mm segments for further processing in 1% OsO4 (with or without en bloc staining in 2% uranyl acetate (UA) in ethanol). Following dehydration in ethanol, rinsing in propylene oxide, and encapsulation in Epon-Araldite, thin sections were examined and photographed with a JEOL-100C microscope.

SEM and TEM evaluation of bacterial adhesion morphology to breast prosthetic biomaterials

1990 ◽  
Vol 48 (3) ◽  
pp. 844-845
Author(s):  
Theresa A. Fassel ◽  
James E. Van Over ◽  
Christopher C. Hauser ◽  
Charles E. Edminston ◽  
James R. Sanger
Keyword(s):  
Late Onset ◽  
Bacterial Species ◽  
Uranyl Acetate ◽  
Ruthenium Red ◽  
Prosthetic Material ◽  
Coagulase Negative Staphylococci ◽  
En Bloc ◽  
Sem And Tem ◽  
Critical Point Drying ◽  
Test Organisms

Coagulase-negative Staphylococci have been implicated in late onset infection of breast prosthetic biomaterials used for augmentation and reconstruction. These prosthesis consist of either gel- or saline-filled smooth silicone rubber or textured polyurethane foam. The morphology of adhesion of staphylococci to the prosthesis is important in understanding their potential role in latent infection. Staphylococcus epidermidis rp62, a polysaccaride mucin producing strain, and Staphylococcus aureus strain 25923 are test organisms. A variety of fixative procedures employing en bloc reagents are compared in both SEM and TEM. Ruthenium red and alcian blue , uranyl acetate and ruthenium red with lysine have been used to preserve extracellular capsular/slime material in several bacterial species.Specimens of prosthetic material are incubated with cells for 18 hrs at 35°C in tryptic soy broth. For SEM, specimens are fixed in 2.5% glutaraldehyde (GA) for 2 hrs and post-fixed in 1% OsO4 for 2.5 hrs. This is followed by a graded ethanol series, critical point drying with CO2 and coating with gold/palladium.

Three-dimensional stiffness in a thoracolumbar en-bloc spondylectomy model: A biomechanical in vitro study

2007 ◽  
Vol 22 (9) ◽  
pp. 957-964 ◽  
Author(s):  
A.C. Disch ◽  
A. Luzzati ◽  
I. Melcher ◽  
K.D. Schaser ◽  
F. Feraboli ◽  
...  
Keyword(s):  
Three Dimensional ◽  
In Vitro Study ◽  
Vitro Study ◽  
En Bloc ◽  
En Bloc Spondylectomy ◽  
Bloc Spondylectomy

scholarly journals Comparative Evaluation of Dimensional Accuracy, Surface Characteristics, and Load Deflection Attributes of 0.019" × 0.025" Stainless Steel Wires Sourced from Six Different Commercial Houses: An In Vitro Study

2020 ◽  
Vol 54 (4) ◽  
pp. 311-320
Author(s):  
Neeraj E Kolge ◽  
Vivek J Patni ◽  
Girish Karandikar ◽  
Ravindranath VK ◽  
Prateek Daga ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Frictional Resistance ◽  
Dimensional Accuracy ◽  
Surface Characteristics ◽  
Steel Wires ◽  
Group 5 ◽  
Group 2 ◽  
Deflection Rate ◽  
Group 1

Aims & Objectives: The aim of the study was to evaluate and compare dimensional accuracy, surface characteristics and load deflection attributes of SS wires sourced from six different commercial houses. Materials & Methods: 0.019” x 0.025” SS wire samples were divided into 6 groups and evaluated and compared for the aforementioned properties. Dimensional accuracy, surface roughness, frictional resistance, load deflection rate and ultimate tensile strength were evaluated and compared. Results: Dimensional accuracy did not vary significantly. Surface Profilometry proved 3M Unitek (Group 1) to be the wire with least irregularities. According to SEM, Modern Orthodontics (Group 6) and 3M Unitek (Group 1) in terms of ‘Sa’ and ‘Sq’ respectively had the smoothest surface finish. SS wires sourced from G&H Orthodontics (Group 2) exhibited least frictional resistance. Load deflection rates varied for all the groups for all three parameters under the study. UTS was best for SS wires sourced from Rabbit Force Orthodontics (Group 5). Conclusion: No wire from a single commercial house excels in all the parameters that were evaluated, each one having its aces and minuses.

scholarly journals Surface Characteristics of Milled and 3D Printed Denture Base Materials Following Polishing and Coating: An In-Vitro Study

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3305
Author(s):  
Pablo Kraemer Fernandez ◽  
Alexey Unkovskiy ◽  
Viola Benkendorff ◽  
Andrea Klink ◽  
Sebastian Spintzyk
Keyword(s):  
Surface Roughness ◽  
3D Printing ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Denture Base ◽  
Liquid Resin ◽  
Base Materials ◽  
Superior Surface ◽  
3D Printed

(1) Background: To date, no information on the polishability of milled and 3D-printed complete denture bases has been provided, which is relevant in terms of plaque accumulation. (2) Methods: three groups (n = 30) were manufactured using the cold-polymerization polymethilmethacrilate, milling (SM) and 3D printing (AM). 10 specimens of each group were left untreated (reference). 10 more specimens were pre-polished (intermediate polishing) and 10 final specimens were highgloss polished. An additional 20 specimens were 3D printed and coated with the liquid resin (coated), 10 of which were additionally polished (coated + polished). For each group Ra and Rz values, gloss value and REM images were obtained. (3). The “highgloss-polished” specimens showed statistically lower Ra and Rz values in the SM, followed by AM and conventional groups. In the AM group statistically lower surfaces roughness was revealed for highgloss-polished, “coated + polished”, and “coated” specimens, respectively. (4) Conclusions: The milled specimens demonstrated superiors surface characteristics than 3D printed and conventionally produced after polishing. The polished specimens demonstrated superior surface characteristics over coated specimens. However, the surface roughness by both polished and coated specimens was within the clinically relevant threshold of 0.2 µm.

scholarly journals Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization – An in vitro Study

2016 ◽  
Vol 17 (4) ◽  
pp. 300-305 ◽  
Author(s):  
JM Gross ◽  
GG Nascimento ◽  
VC Araújo ◽  
MJS Bönecker ◽  
C Furuse
Keyword(s):  
Surface Analysis ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Cleaning Process ◽  
Artificial Bone ◽  
Orthodontic Anchorage ◽  
Synthetic Bone ◽  
Mini Implants ◽  
The Mean

ABSTRACT Objective This study aimed to investigate, in vitro, possible alterations on mini-implants surface after retrieval and if the cleaning process and sterilization can predispose damages. Materials and methods Two commercial mini-implants were tested for deformations after drilling and removing in artificial bone four times. Samples were analyzed by scanning electron microscopy, and surface alterations verified through thread and pitches deformation. To alterations caused by insertion/removal and the cleaning process and sterilization were verified in different procedures: Insertions and sterilization, only insertions, and only sterilization. Photomicrographs were analyzed in order to compare the surface characteristics. Head deformation was verified qualitatively. For a quantitative analysis, distances between threads were measured across the active part of the mini-implants. Results No deformation was observed in both groups. The cleaning and sterilization processes did not provoke alteration in both groups. Nevertheless, the presence of synthetic bone was noted in some samples. The mean distances between implant threads were similar after all steps in all regions in both groups. Conclusion The results suggest that the tested mini-implants can be retrieved without damage of its surface after four cycles of insertion, removal, and sterilization. Clinical significance Mini-implants can be retrieved without damage to its surface after four cycles of insertion, removal, and sterilization in the same patient without representing a biological concern. How to cite this article Gross JM, Nascimento GG, Araújo VC, Bönecker MJS, Furuse C. Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization – An in vitro Study. J Contemp Dent Pract 2016;17(4):300-305.

Effect of different grinding protocols on surface characteristics and fatigue behavior of yttria-stabilized zirconia polycrystalline: An in vitro study

2020 ◽  
Vol 124 (4) ◽  
pp. 486.e1-486.e8 ◽  
Author(s):  
Lívia Fiorin ◽  
Izabela C.M. Moris ◽  
Adriana C.L. Faria ◽  
Ricardo F. Ribeiro ◽  
Renata C.S. Rodrigues
Keyword(s):  
Fatigue Behavior ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Yttria Stabilized Zirconia ◽  
Vitro Study ◽  
Stabilized Zirconia

Effect of an osmotic gradient on antidiuretic hormone-induced endocytosis and hydroosmosis in the toad urinary bladder

1984 ◽  
Vol 247 (2) ◽  
pp. F370-F379
Author(s):  
S. K. Masur ◽  
S. Cooper ◽  
M. S. Rubin
Keyword(s):  
Antidiuretic Hormone ◽  
Apical Membrane ◽  
Surface Characteristics ◽  
Active Role ◽  
Ruthenium Red ◽  
Toad Urinary Bladder ◽  
Osmotic Gradient ◽  
Apical Surface ◽  
Osmotic Permeability

The luminal (apical) border of the epithelium of the bladder in the well-hydrated toad is relatively impermeable, so the bladder usually stores hyposmotic urine. When antidiuretic hormone (ADH) increases apical membrane osmotic permeability dramatically, water is resorbed from hyposmotic mucosal solution; in the presence of hyposmotic or isosmotic mucosal solutions, ADH concomitantly induces exocytosis at the apical border of granule-rich (G) cells. Then ADH induces endocytosis at this border. We describe how an osmotic gradient affects ADH-induced endocytosis and hydroosmosis in vitro. We can assess ADH-induced endocytosis in gradient and no-gradient bladders by applying a double-marker technique that distinguishes among endocytosis, completed internalization of previously surface-attached membrane, and surface invagination by comparing the number of horseradish peroxidase (HRP) uptake bodies (endocytosis) with the number of ruthenium red (RR)-delineated bodies (surface invaginations). With this approach we find that gradient bladders have approximately six times more ADH-induced endocytosis than no-gradient bladders during 45-60 min of ADH stimulation. Furthermore, at 60 min approximately 50% of the HRP-containing structures in no-gradient bladders remain surface connected compared with approximately 1% in gradient bladders. In parallel physiological studies, no-gradient bladders reach and maintain higher induced osmotic permeabilities than gradient bladders. These findings support the hypothesis that endocytosis plays an active role in reestablishing impermeable apical surface characteristics in toad bladder.

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