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This study aims to explore the psychological needs and satisfaction of Chinese, Japanese, and Korean tourists across three phases (i.e. before, during and perceived aftermath) of the COVID-19 pande...

Bisphosphonates are widely used for the treatment of bone diseases, including hypercalcemia and osteoporosis. However, the bioavailability (BA) of orally administered bisphosphonates is low, at approximately 0.9%–1.8%. In addition, the oral administration of bisphosphonates is associated with mucosal damage, including gastritis, gastric ulcer, and erosive esophagitis. Here, to develop a new delivery system for bisphosphonates that improve their BA and safety, we developed polyethylene glycol (PEG)-conjugated alendronate, a novel nitrogen-containing bisphosphonate derivative. We evaluated the absorption and safety of PEG–alendronate in rats following intrapulmonary administration. The BA of PEG–alendronate after intrapulmonary administration was approximately 44 ± 10% in rats, which was similar to that of alendronate (54 ± 3.9%). Alendronate significantly increased total protein concentration and lactate dehydrogenase activity in bronchoalveolar lavage fluid, suggesting that pulmonary epithelium was locally damaged by intrapulmonary administration of alendronate. In marked contrast, PEG–alendronate did not significantly increase the markers following intrapulmonary administration. In an osteoporosis model in rats, intrapulmonary administration of PEG–alendronate effectively inhibited decreases in the width of the growth plate to a level similar to that achieved by intrapulmonary administration of alendronate. These results indicate that pulmonary delivery of PEG–alendronate is a promising approach for the treatment of bone diseases. © 2011 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:3783–3792, 2011

Alendronate, a nitrogen-containing bisphosphonate, has been used as a first-choice drug for the treatment of hypercalcemia and osteoporosis. In the present study, we examined the absorption and safety of alendronate after intrapulmonary administration in rats. The bioavailability (BA) of alendronate after intrapulmonary administration was 47% at a dose of 5 mg/kg, while the BA after oral administration was only 2.9% at a dose of 50 mg/kg in rats. Plasma calcium level, an index of the pharmacological effect of alendronate, was effectively reduced after intrapulmonary administration of alendronate. Furthermore, alendronate continuously reduced the increase in plasma calcium levels for 9 days after a single intrapulmonary administration in rats with 1α-hydroxyvitamin-D(3)-induced hypercalcemia. Intrapulmonary administration of alendronate also effectively suppressed the decrease in bone mass in a rat model of osteoporosis. Alendronate significantly increased the activity of lactate dehydrogenase (LDH) in bronchoalveolar lavage fluid (BALF), indicating that pulmonary mucosal damage was induced by intrapulmonary administration of alendronate. However, co-administration of superoxide dismutase (SOD) with alendronate completely suppressed the alendronate-induced increase in LDH activity in BALF, while maintaining sufficient pulmonary absorption and therapeutic effects of alendronate in rats with 1α-hydroxyvitamin-D(3)-induced hypercalcemia. These findings indicated that the lung is a promising, noninvasive alternative route for the delivery of alendronate in the treatment of bone diseases.

Calcineurin inhibitors are used as immunosuppressive agents for graft-versus-host disease (GVHD) prophylaxis in hematopoietic stem cell transplantation.Since azole antifungals are frequently used for prophylaxis and treatment of infection under immunosuppressive therapy,it is highly possible that azole antifungals will affect blood concentrations of calcineurin inhibitors by inhibiting the drug metabolizing enzyme cytochrome P450 (CYP) 3A4.However,dosage adjustment with individual azole antifungals when administered by different routes has yet to be fully examined.In this study,we examined the effect of azole antifungals on blood concentrations of tacrolimus administered by intravenous constant infusion and cyclosporine administered orally in hematopoietic stem cell transplant patients.Oral voriconazole increased the blood concentration/dose (C/D) ratio of tacrolimus 2.7-fold,a significant increase.Oral itraconazole and intravenous voriconazole increased the C/D ratio 2.4-fold and 2-fold,respectively,but these changes were not statistically significant.The effects of oral and intravenous fluconazole were less potent than those of voriconazole and itraconazole,and tended to increase the C/D ratio of tacrolimus by 1.5-fold.The potencies of interactions between these azole anitifungals and oral cyclosporine blood concentrations were similar to those for intravenous tacrolimus.In consideration of these results,the dosages of calcineurin inhibitors should be reduced by 50-65% when concomitantly administered with voriconazole or itraconazole,and by around 35% in the case of fluconazole.However,dosage adjustment for these drugs should also be based on therapeutic drug monitoring because of the large inter-individual variability of pharmacokinetic interactions.