Establishing Corneal Cross-Linking With Riboflavin and UV-A in the Mouse Cornea In Vivo: Biomechanical Analysis

2015 ◽  
Vol 56 (11) ◽  
pp. 6581 ◽  
Author(s):  
Arthur Hammer ◽  
Sabine Kling ◽  
Marc-Olivier Boldi ◽  
Olivier Richoz ◽  
David Tabibian ◽  
...  
Keyword(s):  
Biomechanical Analysis ◽  
Cross Linking

scholarly journals Chemically-Boosted Corneal Cross-Linking for the Treatment of Keratoconus through a Riboflavin 0.25% Optimized Solution with High Superoxide Anion Release

2021 ◽  
Vol 10 (6) ◽  
pp. 1324
Author(s):  
Cosimo Mazzotta ◽  
Marco Ferrise ◽  
Guido Gabriele ◽  
Paolo Gennaro ◽  
Alessandro Meduri
Keyword(s):  
Superoxide Anion ◽  
Hydroxypropyl Methylcellulose ◽  
Anterior Segment ◽  
Preclinical Study ◽  
Cross Linking ◽  
Specular Microscopy ◽  
The Novel ◽  
Power Setting ◽  
Contralateral Eye

The purpose of this study was to evaluate the effectiveness and safety of a novel buffered riboflavin solution approved for corneal cross-linking (CXL) in progressive keratoconus and secondary corneal ectasia. Following the in vivo preclinical study performed on New Zealand rabbits comparing the novel 0.25% riboflavin solution (Safecross®) containing 1% hydroxypropyl methylcellulose (HPMC) with a 0.25% riboflavin solution containing 0.10% EDTA, accelerated epithelium-off CXL was performed on 10 patients (10 eyes treated, with the contralateral eye used as control) through UV-A at a power setting of 9 mW/cm2 with a total dose of 5.4 J/cm2. Re-epithelialization was evaluated in the postoperative 7 days by fluorescein dye test at biomicroscopy; endothelial cell count and morphology (ECD) were analyzed by specular microscopy at the 1st and 6th month of follow-up and demarcation line depth (DLD) measured by anterior segment optical coherence tomography (AS-OCT) one month after the treatment. We observed complete re-epithelization in all eyes between 72 and 96 h after surgery (88 h on average). ECD and morphology remained unchanged in all eyes. DLD was detected at a mean depth of 362 ± 50 µm, 20% over solutions with equivalent dosage. SafeCross® riboflavin solution chemically-boosted corneal cross-linking seems to optimize CXL oxidative reaction by higher superoxide anion release, improving DLD by a factor of 20%, without adverse events for corneal endothelium.

Cross-linking of fibrinogen by factor XIII zymogen is not apparent in vivo

2003 ◽  
Vol 89 (05) ◽  
pp. 943-944 ◽  
Author(s):  
Patricia DiBello ◽  
John Shainoff
Keyword(s):  
Factor Xiii ◽  
Cross Linking

scholarly journals In vivo protein complex topologies: Sights through a cross-linking lens

PROTEOMICS ◽  
2012 ◽  
Vol 12 (10) ◽  
pp. 1565-1575 ◽  
Author(s):  
James E. Bruce
Keyword(s):  
Protein Complex ◽  
Cross Linking

Load Response of the Tarsal Bones in Patients with Flatfoot Deformity: In Vivo 3D Study

2011 ◽  
Vol 32 (11) ◽  
pp. 1017-1022 ◽  
Author(s):  
Masamitsu Kido ◽  
Kazuya Ikoma ◽  
Kan Imai ◽  
Masahiro Maki ◽  
Ryota Takatori ◽  
...  
Keyword(s):  
Load Condition ◽  
Clinical Analysis ◽  
Biomechanical Analysis ◽  
Talonavicular Joint ◽  
Level Of Evidence ◽  
Tibiotalar Joint ◽  
Talocalcaneal Joint ◽  
Load Response ◽  
Tarsal Bones

Background: The objective of this study was to evaluate the bone rotation of each joint in the hindfoot and compare the load response in healthy feet with that in flatfeet by analyzing the reconstructive three-dimensional (3D) CT image data during weightbearing. Methods: CT scans of 21 healthy feet and 21 feet with flatfoot deformity were taken in non-load condition followed by full-body weightbearing load condition. The images of the hindfoot bones were reconstructed into 3D models. The volume merge method in three planes was used to calculate the position of the talus relative to the tibia in the tibiotalar joint, the navicular relative to the talus in talonavicular joint, and the calcaneus relative to the talus in the talocalcaneal joint. Results: The talar position difference to the load response relative to the tibia in the tibiotalar joint in a flatfoot was 1.7 degrees more plantarflexed in comparison to that in a healthy foot ( p = 0.031). The navicular position difference to the load response relative to the talus in the talonavicular joint was 2.3 degrees more everted ( p = 0.0034). The calcaneal position difference to the load response relative to the talus in the talocalcaneal joint was 1.1 degrees more dorsiflexed ( p = 0.0060) and 1.7 degrees more everted ( p = 0.0018). Conclusion: Referring to previous cadaver study, regarding not only the cadaveric foot, but also the live foot, joint instability occurred in the hindfoot with load in patients with flatfoot. Clinical Relevance: The method used in this study might be applied to clinical analysis of foot diseases such as the staging of flatfoot and to biomechanical analysis to evaluate the effects of foot surgery in the future. Level of Evidence: III

scholarly journals Signaling via β2 Integrins Triggers Neutrophil-Dependent Alteration in Endothelial Barrier Function

2000 ◽  
Vol 191 (11) ◽  
pp. 1829-1840 ◽  
Author(s):  
Narinder Gautam ◽  
Heiko Herwald ◽  
Per Hedqvist ◽  
Lennart Lindbom
Keyword(s):  
Protein S ◽  
Endothelial Barrier ◽  
Cheek Pouch ◽  
Cross Linking ◽  
Endothelial Lining ◽  
Hamster Cheek Pouch ◽  
Cationic Protein ◽  
Edema Formation ◽  
Β2 Integrins

Activation of polymorphonuclear leukocytes (PMNs) and adhesion to the endothelial lining is a major cause of edema formation. Although known to be dependent on the function of β2 integrins (CD11/CD18), the precise mechanisms by which adherent PMNs may impair endothelial barrier capacity remain unclear. Here, the role of transmembrane signaling by β2 integrins in PMN-induced alterations in tight junctional permeability of cultured endothelial cell (EC) monolayers was investigated. PMN activation, in the absence of proinflammatory stimuli, was accomplished through antibody cross-linking of CD11b/CD18, mimicking adhesion-dependent receptor engagement. CD18 cross-linking in PMNs added to the EC monolayer provoked a prompt increase in EC permeability that coincided with a rise in EC cytosolic free Ca2+ and rearrangement of actin filaments, events similar to those evoked by chemoattractant PMN activation. Cell-free supernatant obtained after CD18 cross-linking in suspended PMNs triggered an EC response indistinguishable from that induced by direct PMN activation, and caused clear-cut venular plasma leakage when added to the hamster cheek pouch in vivo preparation. The PMN-evoked EC response was specific to β2 integrin engagement inasmuch as antibody cross-linking of l-selectin or CD44 was without effect on EC function. Our data demonstrate a causal link between outside-in signaling by β2 integrins and the capacity of PMNs to induce alterations in vascular permeability, and suggest a paracrine mechanism that involves PMN-derived cationic protein(s) in the cellular crosstalk between PMNs and ECs.

scholarly journals Native cross-links in collagen fibrils induce resistance to human synovial collagenase

1979 ◽  
Vol 181 (3) ◽  
pp. 639-645 ◽  
Author(s):  
C A Vater ◽  
E D Harris ◽  
R C Siegel
Keyword(s):  
Lysyl Oxidase ◽  
Collagen Fibrils ◽  
Bone Collagen ◽  
Collagen Molecule ◽  
Cross Linking ◽  
Pathological Conditions ◽  
Insoluble Material ◽  
Induce Resistance ◽  
Cross Links

A model system consisting of highly purified lysyl oxidase and reconstituted lathyritic chick bone collagen fibrils was used to study the effect of collagen cross-linking on collagen degradation by mammalian collagenase. The results indicate that synthesis of approx. 0.1 Schiff-base cross-link per collagen molecule results in a 2–3-fold resistance to human synovial collagenase when compared with un-cross-linked controls or samples incubated in the presence of beta-aminopropionitrile to inhibit cross-linking. These results confirm previous studies utilizing artificially cross-linked collagens, or collagens isolated as insoluble material after cross-linking in vivo, and suggest that increased resistance to collagenase may be one of the earliest effects of cross-linking in vivo. The extent of intermolecular cross-linking among collagen fibrils may provide a mechanism for regulating the rate of collagen catabolism relative to synthesis in normal and pathological conditions.

scholarly journals Additional evidence for a proform to tropoelastin from chick aorta

1979 ◽  
Vol 177 (2) ◽  
pp. 559-567 ◽  
Author(s):  
C S Heng-Khoo ◽  
R B Rucker ◽  
K W Buckingham
Keyword(s):  
Basic Protein ◽  
Cross Linking ◽  
Protein Subunit ◽  
Deficient Diet ◽  
Culture In Vitro ◽  
One Step

Evidence is presented for the presence of precursor to tropoelastin in chick arterial extracts. The precursor is approx. 100 000 daltons in size. It is suggested to be a precursor to tropoelastin (72 000 daltons). This protein may be observed in culture in vitro if appropriate precautions are taken to inhibit proteolysis. Once synthesized, it appears to be converted into tropoelastin within 10–20 min. The protein may also be detected in vivo. When 1-day-old cockerels were fed on a copper-deficient diet (less than 1 p.p.m. to inhibit cross-linking) containing epsilon-aminohexanoic acid (0.2%) to retard proteolysis and then injected wiht [3H]valine, extraction of arterial proteins 12h after injection resulted in detection of two major peaks of [3H]valine-labelled protein with pI values of pH 7.0 and 5.0 respectively. The protein that focused at pH 7.0 was estimated to be about 100 000 daltons in size and could be shown to be converted into a more basic protein with the properties of tropoelastin. It is speculated that the protein with pI 5.0 may be yet another extension peptide. The data appear to be in keeping with similar observations by ourselves and others that a proform of tropoelastin exists, and, in at least one step before conversion into tropoelastin, exists as a 100 000-dalton protein subunit.

scholarly journals Antigenicity of the infected-erythrocyte and merozoite surfaces in Falciparum malaria.

1979 ◽  
Vol 150 (5) ◽  
pp. 1241-1254 ◽  
Author(s):  
S G Langreth ◽  
R T Reese
Keyword(s):  
Plasmodium Falciparum ◽  
Falciparum Malaria ◽  
Infected Erythrocyte ◽  
Falciparum Infection ◽  
Human Erythrocytes ◽  
Cross Linking ◽  
Common Antigens

The antigenicity of altered structures induced by Plasmodium falciparum in the membranes of infected Aotus monkey and human erythrocytes was examined. Antisera were obtained from monkeys made immune to malaria. Bound antibodies were shown to be localized on the knob protrusions of infected erythrocytes of both human and monkey origin and from both in vitro and in vivo infections. Therefore, P. falciparum infection has produced similar antigenic changes in the erythrocyte surfaces of both man and monkey. Uninfected erythrocytes and all knobless-infected erythrocytes bound no antibody from immune sera. Strains of P. falciparum from widely different geographic areas that were cultured in vitro in human erythrocytes induced structures (knobs) which have common antigenicity. Merozoites were agglutinated by cross-linking of their cell coats when incubated with immune sera. The binding of ferritin-labeled antibody was heavy on the coats of both homologous and heterologous strains of the parasite, indicating that the merozoite surfaces of these strains share common antigens.

Sign in / Sign up

Export Citation Format

Share Document