Effect of l-Arginine treatment on the in vitro stability of electrospun aligned chitosan nanofiber mats

2020 ◽  
Vol 91 ◽  
pp. 106758 ◽  
Author(s):  
Paola Nitti ◽  
Nunzia Gallo ◽  
Barbara Palazzo ◽  
Alessandro Sannino ◽  
Alessandro Polini ◽  
...  
Keyword(s):  
Chitosan Nanofiber ◽  
Nanofiber Mats ◽  
In Vitro Stability

scholarly journals Electrospun Biomaterials from Chitosan Blends Applied as Scaffold for Tissue Regeneration

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1037
Author(s):  
Christian Enrique Garcia Garcia ◽  
Frédéric Bossard ◽  
Marguerite Rinaudo
Keyword(s):  
Tissue Engineering ◽  
Chitosan Film ◽  
Electrospinning Technique ◽  
Force Microscopy ◽  
Atomic Force ◽  
Chitosan Nanofiber ◽  
Chitosan Blends ◽  
Nanofiber Mats ◽  
Cell Force

Our objective in this work was to summarize the main results obtained in processing pure chitosan and chitosan/hyaluronan complex in view of biomedical applications, taking advantage of their original properties. In addition, an electrospinning technique was selected to prepare nanofiber mats well adapted for tissue engineering in relation to the large porosity of the materials, allowing an exchange with the environment. The optimum conditions for preparation of purified and stable nanofibers in aqueous solution and phosphate buffer pH = 7.4 are described. Their mechanical properties and degree of swelling are given. Then, the prepared biomaterials are investigated to test their advantage for chondrocyte development after comparison of nanofiber mats and uniform films. For that purpose, the adhesion of cells is studied by atomic force microscopy (AFM) using single-cell force spectroscopy, showing the good adhesion of chondrocytes on chitosan. At the end, adhesion and proliferation of chondrocytes in vitro are examined and clearly show the interest of chitosan nanofiber mats compared to chitosan film for potential application in tissue engineering.

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

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
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.

Rhenium-188 Labeled Hydroxyapatite and Rhenium-188 Sulfur Colloid

1997 ◽  
Vol 36 (02) ◽  
pp. 71-75 ◽  
Author(s):  
S. Glatz ◽  
S. N. Reske ◽  
K. G. Grillenberger
Keyword(s):  
Synovial Fluid ◽  
Ph Value ◽  
Surgical Removal ◽  
Radiation Synovectomy ◽  
Sulfur Colloid ◽  
Target Organs ◽  
Aseptic Conditions ◽  
In Vitro Stability ◽  
Potential Use

Summary Aim: One therapeutic approach to rheumatoid arthritis and other inflammatory arthropathies besides surgical removal of inflamed synovium is radiation synovectomy using beta-emitting radionuclides to destroy the affected synovial tissue. Up to now the major problem associated with the use of labeled particles or colloids has been considerable leakage of radionuclides from the injected joint coupled with high radiation doses to liver and other non target organs. In this study we compared 188Re labeled hydroxyapatite particles and 188Re rhenium sulfur colloid for their potential use in radiation synovectomy. Methods: To this end we varied the labeling conditions (concentrations, pH-value, heating procedure) and analyzed the labeling yield, radiochemical purity, and in vitro stability of the resulting radiopharmaceutical. Results: After optimizing labeling conditions we achieved a labeling yield of more than 80% for 188Re hydroxyapatite and more than 90% for the rhenium sulfur colloid. Both of the radiopharmaceuticals can be prepared under aseptic conditions using an autoclav for heating without loss of activity. In vitro stability studies using various challenge solutions (water, normal saline, diluted synovial fluid) showed that 188Re labeled hydroxyapatite particles lost about 80% of their activity within 5 d in synovial fluid. Rhenium sulfur colloid on the other hand proved to be very stable with a remaining activity of more than 93% after 5 d in diluted synovial fluid. Conclusion: These in vitro results suggest that 188Re labeled rhenium sulfur colloid expects to be more suitable for therapeutic use in radiation synovectomy than the labeled hydroxyapatite particles.

Leukocyte labeling with 99mTc-HMPAO. The role of the in vitro stability of HMPAO on the labeling efficacy and image quality

1994 ◽  
Vol 21 (6) ◽  
pp. 893-895 ◽  
Author(s):  
Miklós Papós ◽  
Jenő Láng ◽  
Mária Rajtár ◽  
László Csernay
Keyword(s):  
Image Quality ◽  
Leukocyte Labeling ◽  
In Vitro Stability ◽  
99Mtc Hmpao

In Vivo Testing of Sericin-Polyurethane Nanofiber Mats for Wound Healing in Rats

2017 ◽  
Vol 751 ◽  
pp. 581-585 ◽  
Author(s):  
Piyaporn Kampeerapappun ◽  
Pornpen Siridamrong
Keyword(s):  
Wound Healing ◽  
Healing Process ◽  
Active Agent ◽  
L929 Cell ◽  
Wound Healing Process ◽  
Original Size ◽  
Nanofiber Mats ◽  
Dressing Materials

The objective of this study was to investigate sericin-polyurethane nanofiber cover (SUC) for wound dressing materials in a rat skin. Sericin-polyurethane blended nanofibers were fabricated by using electrospinning. The composition of 3%w/v polyurethane in ethanol and 19% w/v sericin were blended and electrospun at 15 kV, 20 cm from tip to collector with a feed rate of 6.2 ml/hr. The mats, approximately 1.5 mm thick, were sterile by gamma irradiation with a radiation dose of 15 kGy. The samples of in vitro and in vivo testing were separated into three groups; gauze, polyurethane nanofiber cover (UC), and SUC. In vitro cultured L929 cell lines were investigated with inverted microscope. It was found that cells migrated to SCU. For in vivo tests, the remaining wound in rats was measured on day 2-14 after excision. Compared to original size of wound samples, the size of the wound remained 24% for SUC, 33% for gauze, and 34% for UC at day 8. The sericin, an active agent, contained in SUC mats was about 5 µl at 1.5 ×1.5 cm. It can be concluded that sericin is non-toxic to cells and can promote wound healing process in rats.

Studies of two temperature-sensitive mutants of Mengo virus

1979 ◽  
Vol 57 (6) ◽  
pp. 902-913 ◽  
Author(s):  
Patrick W. K. Lee ◽  
John S. Colter
Keyword(s):  
Rna Synthesis ◽  
Viral Rna ◽  
Temperature Sensitive ◽  
Supporting Evidence ◽  
Structural Polypeptide ◽  
Infected Cells ◽  
Mengo Virus ◽  
In Vitro Stability

Studies of the synthesis of viral ribonucleates and polypeptides in cells infected with two RNA−ts mutants of Mengo virus (ts 135 and ts 520) have shown that when ts 135 infected cells are shifted from the permissive (33 °C) to the nonpermissive (39 °C) temperature: (i) the synthesis of all three species of viral RNA (single stranded, replicative form, and replicative intermediate) is inhibited to about the same extent, and (ii) the posttranslational cleavage of structural polypeptide precursors A and B is partially blocked. Investigations of the in vivo and in vitro stability of the viral RNA replicase suggest that the RNA− phentotype reflects a temperature-sensitive defect in the enzyme. The second defect does not appear to result from the inhibition of viral RNA synthesis at 39 °C, since normal cleavage of polypeptides A and B occurs in wt Mengo-infected cells in which viral RNA synthesis is blocked by cordycepin, and at the nonpermissive temperature in ts 520 infected cells. Considered in toto, the evidence suggests that ts 135 is a double mutant.Subviral (53 S) particles have been shown to accumulate in ts 520 (but not ts 135) infected cells when cultures are shifted from 33 to 39 °C. This observation provides supporting evidence for the proposal that this recently discovered particle is an intermediate in the assembly pathway of Mengo virions.

Assessment of in vitro stability: a call for harmonization across studies

2018 ◽  
Vol 56 (5) ◽  
pp. e121-e124 ◽  
Author(s):  
Pierre Bastin ◽  
Julien Favresse ◽  
Corentin Streel ◽  
Diane Maisin ◽  
Catherine Fillée ◽  
...  
Keyword(s):  
In Vitro Stability

Nitrate removal from liquid effluents using microalgae immobilized on chitosan nanofiber mats

2012 ◽  
Vol 14 (10) ◽  
pp. 2682 ◽  
Author(s):  
Ela Eroglu ◽  
Vipul Agarwal ◽  
Michael Bradshaw ◽  
Xianjue Chen ◽  
Steven M. Smith ◽  
...  
Keyword(s):  
Nitrate Removal ◽  
Chitosan Nanofiber ◽  
Nanofiber Mats

Synthesis, Proteolytic Stability, and In vitro Evaluation of DOTA Conjugated p160 Peptide Based Radioconjugates: [177Lu]Lu-DOTA-p160

2021 ◽  
Author(s):  
Jasleen Kaur ◽  
Karim Arroub ◽  
Alexander Drzezga ◽  
Klaus Schomaecker ◽  
Sanjay Mathur
Keyword(s):  
Biological Evaluation ◽  
In Vitro Evaluation ◽  
Enzymatic Stability ◽  
Proteolytic Stability ◽  
In Vitro Stability

In this work, we describe the synthesis, in-vitro stability, and preliminary biological evaluation of [177Lu]Lu-DOTA-p160 peptide-based radiopharmaceuticals. Our findings highlight that all DOTA-p160-peptide radioconjugates exhibit favorable proteolytic and enzymatic stability...

Sign in / Sign up

Export Citation Format

Share Document