RESUMO
Recently, smaller-size electron-beam (EB) accelerators have offered EB irradiation in laboratory systems. Therefore, polymer surface treatments with low-energy EB have been developed in the past years. For high adhesion strength, low-energy EB treatment is also a promising method in comparison to plasma surface treatment. In the plasma treatment, the mechanism of the effect on the adhesion properties has been proved and the excess treatments led to the formation of a weak boundary layer and reduction of adhesion strength. In contrast, the low-energy EB possesses high penetration ability. In this work, we focused on the surface treatments of isotactic polypropylene (it.PP) with low-energy EB irradiation for adhesion. The dependence of adhesion strength on the absorbed dose of electron beam was evaluated, and the mechanism of electron beam on the adhesion properties was investigated from various perspectives of surface properties and morphology. Compared to that of plasma-treated it.PP, the adhesion strength of it.PP with electron-beam irradiation increased drastically. We proved that the radical was generated in the substrates after electron-beam treatments and would form covalent bonds between adhesives and substrates, which achieved higher adhesion than plasma treatments. In addition, the electron beam reached effectively a deep region from the top surface of the substrates and provided larger adhesion strength.
RESUMO
We previously reported a high incidence of kerato-conjunctivitis in patients receiving high-dose cytarabine following total body irradiation (TBI) as a conditioning for hematopoietic stem cell transplantation (HSCT) even on prophylaxis with topical corticosteroid. This study aimed to evaluate whether addition of eye rinse, which was designed to remove cytarabine from ocular surface, further reduces the incidence of kerato-conjunctivitis in the same setting. Seventy-six patients receiving cytarabine at a dose of 3 g/m(2) every 12 h for 4 days after receiving TBI (12 Gy) as conditioning for HSCT were evaluated. All patients received betamethasone sodium phosphate eye drops. Twenty-three patients were further instructed to rinse their eyes with sterile saline every 10-15 min during and for two additional hours after the completion of each cytarabine infusion. Among 23 patients with eye rinse, Grades 2-3 and 1-3 kerato-conjunctivitis were observed in 4 (17.4%) and 5 patients (21.7%), respectively. These incidences were significantly lower than those [35 (66.0%) and 41 (77.4%)] observed in 53 patients without eye rinse (P < 0.001 and P < 0.00001, respectively). These results strongly suggest that eye rinse effectively reduces the incidence and severity of cytarabine-induced kerato-conjunctivitis in HSCT recipients who receive high-dose cytarabine following TBI.
