It has been well known that fluorinated polyurethanes exhibit unique low surface energy, biocompatibility, biostability and nonsticking behavior. Consequently, these polymers have attracted considerable interest. In this study, the effect of various concentrations of fluorinated polyurethanes in the polyurethanes on the surface structures of the blends and their hemocompatibility were investigated by XPS, AFM, contact angle and platelet adhesion. It was found that the high concentration fluorine on the outer surfaces of the blends obtained with the low concentration of fluorinated polyurethanes (F: 0.342 wt%) in the blends was the same as that of the fluorinated poly(ether urethane)s, and all of the blends and the fluorinated poly(ether urethane)s had good hemocompatibility, compared with poly(ether urethane)s. The polymer blends and fluorinated poly(ether urethane)s suppressed platelet adhesion due to their high hydrophobicity and low surface tension. The XPS, AMF and contact angle results indicated that the high hydrophobicity of outer surface of the polyurethane blends is independent of the fluorinated polyurethanes content in the polymer blends but related to the concentration of the CF3 groups because the lower critical surface tensions and higher contact angle of many fluorinated surfaces reflect the concentration of CF3 groups.
Coated Materials, Biocompatible ; chemistry ; Ethers ; Fluorine ; Humans ; Platelet Adhesiveness ; Polyurethanes ; chemistry ; pharmacology ; Prostheses and Implants ; Surface Properties

OBJECTIVETo study the interaction of fluorine (F), calcium (Ca) and iodine (I) on body weight of rats.

METHODSOne-month-old Wistar rats were randomly divided into 8 groups: moderate concentrations of F, Ca, I (group 1); moderate concentrations of F, I and high concentration of Ca (group 2); moderate concentrations of Ca, I and high concentration of F (group 3); moderate concentration of I and high concentrations of F, Ca (group 4); moderate concentrations of F, Ca and low concentration of I (group 5); moderate concentration of F,high concentration of Ca and low concentration of I (group 6); moderate concentration of Ca, high concentration of F and low concentration of I (group 7); high concentrations of F, Ca and low concentration of I (group 8) based on 2 x 2 x 2 factorial design. The moderate concentration of F was 90 microg/d and the high concentration of F was 2700 microg/d. The moderate Ca concentration was 13 mg/d and the high Ca concentration was 260 mg/d. The moderate concentration of I was 3.5 microg/d and the low concentration of I was 0.23 microg/d. After twenty weeks, body weight was measured.

RESULTSAccording to the results of factorial ANOVA, significant interaction effects of F with Ca were found (F = 5.933, P = 0.017). The empty body weight was measured at the end of the fifth month. When both iodine and fluorine were at the optimal level, the weight of group 2 [(262.5 +/- 47.1) g] and group 1 [(307.9 +/- 55.0) g] showed significant difference (t = 4.24, P < 0.05). When both iodine and fluorine were at low level, the weight of group 6 [(248.8 +/- 30.0) g] and group 5 [(293.3 +/- 19.7) g] showed significant difference (t = 4.16, P < 0.05). Animals with optimal iodine and calcium [(269.3 +/- 27.3) g] showed significant difference compared to the weight of low level iodine and optimal fluorine [(307.9 +/- 55.0) g]. When the low level iodine and optimal calcium were applied, weight of group 7 [(261.9 +/- 31.3) g] and group 5 [(293.3 +/- 19.7) g] showed significant difference. (t = 2.94, P < 0.05).

CONCLUSIONInteraction effects of F with Ca were found on body weight in rats.

Animals ; Body Weight ; drug effects ; Calcium, Dietary ; pharmacology ; Drug Interactions ; Female ; Fluorides ; Fluorine ; pharmacology ; Iodine ; pharmacology ; Male ; Rats ; Rats, Wistar

We investigated the mechanism of Cl- secretion by fluoroaluminate(AlF4-) and sodium orthovanadate(vanadate) using the human colonic T84 cell line. T84 cell monolayers grown on collagen-coated filters were mounted in Ussing chambers to measure short circuit current(ISC). Serosal addition of AlF4- or vanadate to T84 monolayers produced a sustained increase in ISC. Removal of Ca2+ from the serosal bathing solution partially inhibited AlF4-(-)and vanadate-induced ISC, and readministration of Ca2+ restored AlF4-(-)and vanadate-induced ISC. Carbachol application in the presence of forskolin, AlF4- or vanadate induced a synergistic increase of ISC. Forskolin and vanadate significantly increased cellular cAMP level, while carbachol and AlF4- did not. Carbachol, AlF4- and vanadate significantly increased [Ca2+]i. After Na+ in mucosal bathing solution was replaced with K+, and the mucosal membrane of T84 cell was permeabilized with amphotericin B, AlF4-, vanadate, and carbachol increased K+ conductance, but forskolin did not. After sodium chloride in serosal bathing solution was replaced with sodium gluconate and the serosal membrane was permeabilized with nystatin, forskolin, AlF4-, and vanadate increased Cl- conductance, but carbachol did not. AlF4-(-)induced ISC was remarkably inhibited by the pretreatment of pertussis toxin(2 micrograms/ml) for 2 hours. These results indicate that AlF4- and vanadate can increase Cl- secretion via simultaneous stimulation of Cl- channel and K+ channel in T84 cells. However, the AlF4- action is mostly attributed to stimulation of pertussis toxin-sensitive G-proteins, whereas the vanadate action mostly results from G protein-independent mechanisms.
Aluminum/*pharmacology ; Amphotericin B/pharmacology ; Carbachol/pharmacology ; Cell Polarity ; Cells, Cultured/drug effects ; Chloride Channels/drug effects/*physiology ; Chlorides/*physiology ; Colon ; Electrophysiology ; Fluorine/*pharmacology ; Forskolin/pharmacology ; GTP-Binding Proteins/physiology ; Human ; Pertussis Toxin ; Potassium/pharmacology ; Potassium Channels/drug effects/physiology ; Second Messenger Systems ; Signal Transduction ; Support, Non-U.S. Gov't ; Vanadates/*pharmacology ; Virulence Factors, Bordetella/pharmacology