Effects of combined therapy of alendronate and low-intensity pulsed ultrasound on metaphyseal bone repair after osteotomy in the proximal tibia of glucocorticoid-induced osteopenia rats

OBJECTIVES: Glucocorticoid (GC) treatment inhibits activation of runt-related transcription factor 2 (Runx2), which is essential for osteoblast differentiation from stem cells. As a result, GC treatment results in bone loss, GC-induced osteoporosis (GIO), elevated fracture risk, and delayed bone healing. Bisphosphonates such as alendronate (ALN) are recommended for treating or preventing GIO, and lowintensity pulsed ultrasound (LIPUS) facilitates fracture healing and maturation of regenerated bone. Combined therapy with ALN and LIPUS may stimulate cancellous bone healing in GIO rats. Here, we examined the effect of ALN and LIPUS on cancellous bone osteotomy repair in the proximal tibia of GIO rats. METHODS: Prednisolone (10 mg/kg body weight/day) was administered for 4 weeks to induce GIO in 6-month-old female Sprague-Dawley rats. Tibial osteotomy was then performed and daily subcutaneous injection of ALN (1-µg/kg body weight) was subsequently administered alone or in combination with LIPUS (20 min/day) for 2 or 4 weeks. RESULTS: ALN significantly increased bone mineral density (BMD) at 2 and 4 weeks, and ALN + LIPUS significantly increased BMD at 4 weeks. Bone union rates were significantly increased after 2 and 4 weeks ALN and ALN + LIPUS treatment. Lastly, ALN and ALN + LIPUS significantly increased the proportion of Runx2 positive cells at 4 weeks. CONCLUSIONS: ALN monotherapy and combined ALN and LUPUS treatment augmented BMD and stimulated cancellous bone repair with increased Runx2 expression at the osteotomy site in GIO rats. However, the combined treatment had no additional effect on cancellous bone healing compared to ALN monotherapy.

Body mass index correlated with forced expiratory volume in 1 second/forced vital capacity in a population with a relatively low prevalence of obesity / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Obesity is the most common metabolic disease in the world. However, the relationship between obesity and lung function is not fully understood. Although several longitudinal studies have shown that increases in body weight can lead to reductions in pulmonary function, whether this is the case with the Japanese population and whether high body mass index (BMI) status alone represents an appropriate predictor of obstructive lung dysfunction remains unclear. The purpose of present study was to estimate the effect of BMI on lung function measured by spirometry of Japanese patients in general clinics. We measured BMI and performed spirometry on screening patients who had consulted general clinics.</p><p><b>METHODS</b>Subjects comprised 1231 patients ≥ 40 years of age (mean age (65.0 ± 12.0) years, 525 men, 706 women) who had consulted clinics in Nagasaki Prefecture, Japan, for non-respiratory disease. BMI was calculated and lung function was measured by spirometry.</p><p><b>RESULTS</b>BMI was found to be positively correlated with forced expiratory volume in 1 second (FEV(1))/forced vital capacity (FVC) in men and with maximum mid-expiratory flow (MMF) in all subjects. Following adjustment for relevant factors, a significant positive correlation between BMI and FEV(1)/FVC was identified for all subjects. Comparison between subjects with normal BMI (18.5 - 25.0) and higher BMI (25.1 - 30.0) also demonstrated that FEV(1)/FVC and percentage of predicted maximum mid-expiratory flow (%MMF) were significantly higher in the latter subjects.</p><p><b>CONCLUSIONS</b>In a population without marked respiratory disease, higher BMI subjects showed less obstructive pulmonary dysfunction compared to normal BMI subjects. High BMI status alone may be inappropriate as a predictor of obstructive lung dysfunction, particularly in populations with a low prevalence of obesity.</p>