orabase and Hemolysis

Inspired by antimicrobial peptides (AMP) which could alleviate drug resistance pressure, antimicrobial peptide mimics (AMPMs) were designed timely. Here, carboxymethyl cellulose (CMC) -based AMPMs were constructed by introducing different diamines on CMC effectively. Firstly, CMC was degraded to be oligomers with different molecular weights, followed by amination reactions with different diamines respectively. After protonation, a series of AMPMs with different structures were synthesized successfully. Their antibacterial effect has been evaluated by dynamic growth curves and microdilution method. The images snapped by the confocal laser scanning microscope and transmission electron microscope have fully proved its great lethality. And the antibacterial mechanism measured by flow cytometry analysis and zeta potential detection demonstrated that the destruction of membrane potential leads to bacteria death. The excellent blood compatibility and negligible drug resistance has also been confirmed. In addition, the synthesis method is simple and environmental-friendly.

Topics: Anti-Bacterial Agents; Anti-Infective Agents; Carboxymethylcellulose Sodium; Hemolysis; Humans; Materials Testing; Microbial Sensitivity Tests; Molecular Mimicry; Pore Forming Cytotoxic Proteins; Staphylococcus aureus

Topics: Anti-Bacterial Agents; Apoptosis; Bandages; Carboxymethylcellulose Sodium; Chitosan; Drug Carriers; Drug Liberation; Fluorouracil; Hemolysis; Hep G2 Cells; Humans; Hydrogels; Mechanical Phenomena; Rheology; Wound Healing

We present the use of a natural derivative, dialdehyde carboxymethyl cellulose (DCMC) as the cross-linker for the preparation of spongy collagen cryogels by freezing-thawing method. The DCMC has been characterized by laser light scattering (LLS), showing the molecular weight of 2.38 × 10(5)g/mol. FT-IR studies demonstrate that the cross-linking reaction and the cryogenic treatment do not destroy the triple helix of collagen. SEM images indicate that the cryogel has a heterophase structure with interconnecting macropores. DSC measurements reveal that the incorporation of a very small amount of DCMC can significantly improve the thermal stability of collagen. Moreover, the cryogels exhibit fast swelling rate, and their equilibrium swelling ratio is related to DCMC content and pH-dependent. The in vitro blood-compatibility tests prove that the introduction of DCMC does not cause the reducing performance in hemolysis and blood clotting compared with pure collagen. Hence, the low-cost and non-toxic nature of DCMC confers the cryogel great potential in tissue engineering and other biomedical applications.

Topics: Animals; Blood Coagulation; Calorimetry, Differential Scanning; Carboxymethylcellulose Sodium; Cattle; Collagen; Cross-Linking Reagents; Cryogels; Hemolysis; Hydrogen-Ion Concentration; Kinetics; Lasers; Rabbits; Scattering, Radiation; Spectroscopy, Fourier Transform Infrared; Temperature

Ophthalmic delivery systems such as ocular inserts are useful strategies to improve the ocular bioavailability of topically administered drugs. In the present study polyvinyl alcohol and sodium carboxymethylcellulose based ocular inserts were prepared by solution casting for sustained drug delivery of ciprofloxacin for treatment of topical infections. The polymers were esterified and the formation of ester bonds was confirmed by Fourier transform infrared spectroscopy. The inserts had a smooth structure with a surface roughness of 7.3 nm. Inserts were found to be wettable by simulated tear fluid with contact angle <45 degrees . Mechanical testing results indicated that the tensile strength of polyvinyl alcohol-sodium carboxymethylcellulose (10:2 wt.%) inserts was up to 8.9 + or - 1.9 MPa, which is adequate to resist the pressure likely to be exerted during application. In vitro drug release kinetics showed sustained release of ciprofloxacin for up to 48 h from the inserts. Sodium fluorescein-loaded inserts showed higher penetration of the dye in the posterior segment tissues of explanted goat eye balls as compared with an eye drop solution of sodium fluorescein. The inserts were non-toxic to corneal epithelial cells and showed no signs of acute ocular toxicity in in vivo studies in albino rabbits.

Topics: Animals; Anti-Bacterial Agents; Biocompatible Materials; Carboxymethylcellulose Sodium; Cell Line; Ciprofloxacin; Drug Delivery Systems; Escherichia coli; Eye; Goats; Hemolysis; Humans; Mechanical Phenomena; Membranes, Artificial; Microbial Sensitivity Tests; Microscopy, Atomic Force; Microscopy, Electron, Scanning; Mucins; Polyvinyl Alcohol; Spectroscopy, Fourier Transform Infrared; Staphylococcus aureus; Toxicity Tests, Acute; Wettability

The fate of highly purified properdin (P) upon introduction into normal human serum or properdin-depleted serum (RP) was investigated. It was observed that, concomitant with the activation of the alternate pathway components, properdin underwent immunochemical alterations characterized by a shift in mobility from gamma2 to beta2 position and by an increase in the sedimentation rate from 5.1S to between 6.8 and 9.3S. The immunoelectrophoretic behavior of C3 was also altered with the appearance of a beta2 arc in addition to the beta1C arc. The immunochemical properties of altered P resemble those of "native" properdin in fresh serum. The principle in serum (designated factor F) mediating these changes is a euglobulin with an approximate sedimentation rate and molecular weight of 9.0S and 250,000 daltons, respectively. The alteration in the immunochemical properties of P may be due to aggregation of P molecules or a complex formation between P and a serum euglobulin (probably C3) mediated by factor F and it is associated with loss of ability of P in initiate the alternate pathway of complement activation upon interaction with serum.

Topics: Animals; Carboxymethylcellulose Sodium; Centrifugation, Density Gradient; Chromatography; Chromatography, Gel; Complement System Proteins; Dextrans; Electrophoresis, Disc; Fibrinolysin; Hemolysis; Humans; Immune Sera; Immunochemistry; Immunoelectrophoresis; Iodine Radioisotopes; Isoflurophate; Molecular Weight; Properdin; Rabbits; Serum Globulins; Trypsin; Trypsin Inhibitors; Ultracentrifugation; Zymosan

Mg++, Mn++ and Co++ activate the C system as judged by the reduction in cobra venom factor indeed hemolysis, and cleavage of properdin factor B and C3. The maximum effect requires the addition of 5 to 10 mM of these cations to dialyzed sera respond in similar fashion indicating that these divalent cations can trigger the alternative pathway without the addition other activating agents.

Topics: Animals; Blood Coagulation Factors; Calcium; Carboxymethylcellulose Sodium; Cations, Divalent; Chromatography, Affinity; Chromatography, DEAE-Cellulose; Cobalt; Complement C3; Complement System Proteins; Dextrans; Edetic Acid; Egtazic Acid; Guinea Pigs; Hemolysis; Humans; Immune Sera; Immunoelectrophoresis; Magnesium; Manganese; Properdin; Rabbits; Rats; Serum Globulins; Snakes; Venoms

The hemolytic activity of fibrous asbestos varieties and of fibrous or granular silica dust can be markedly reduced by adsorption of polymers. Polyanions exert a specific action on asbestos, particularly chrysotile, whereas silica is inactivated by nonionic polymers. A high degree of reduction of the lytic action by comparatively small amounts of the antagonistic polymers can be demonstrated after short exposure to concentrations of 0.1-0.4 mg/ml of appropriate polymers. Inactivation is based on stable adsorption. Repeated washings of inactivated mineral sediments or exposure to elevated temperatures (80-120 degrees C) produced no essential loss of the reduction of lytic potency. In one example, inactivation of chrysotile by sodium alginate, depolymerization by ascorbic acid was also ineffective.

Topics: Adsorption; Alginates; Asbestos; Ascorbic Acid; Carboxymethylcellulose Sodium; Chondroitin Sulfates; Hemolysis; Hot Temperature; Povidone; Silicon Dioxide; Surface Properties; Time Factors