To date, few studies have investigated the feasibility of the loop-mediated isothermal amplification (LAMP) assay for identifying pathogens in tissue samples. This study aimed to investigate the feasibility of LAMP for the rapid detection of methicillin-susceptible or methicillin-resistant Staphylococcus aureus (MSSA or MRSA) in tissue samples, using a bead-beating DNA extraction method. Twenty tissue samples infected with either MSSA (n = 10) or MRSA (n = 10) were obtained from patients who underwent orthopedic surgery for suspected musculoskeletal infection between December 2019 and September 2020. DNA was extracted from the infected tissue samples using the bead-beating method. A multiplex LAMP assay was conducted to identify MSSA and MRSA infections. To recognize the Staphylococcus genus, S. aureus, and methicillin resistance, 3 sets of 6 primers for the 16S ribosomal ribonucleic acid (rRNA) and the femA and mecA genes were used, respectively. The limit of detection and sensitivity (detection rate) of the LAMP assay for diagnosing MSSA and MRSA infection were analyzed. The results of this study suggest that the LAMP assay performed with tissue DNA samples can be a useful diagnostic method for the rapid detection of musculoskeletal infections caused by MSSA and MRSA.
ONFH with large or lateral-located lesion is challenging due to difficulty of regeneration. We introduce novel tissue engineering technique using ex vivo expanded bone marrow stromal cell seeded on calcium metaphosphate (CMP) scaffold to regenerate dead bone for these challenging cases. Ten millilitres of bone marrow was aspirated from iliac crest and mononuclear cells were collected. These cells were expanded and differentiated to osteoblast-lineage cells using osteogenic media and autologous serum for 2–4 weeks ex vivo. Porous bead-form scaffolds were made of CMP and cells were seeded in a density of million/ml³ into 20 to 30 beads for 1 hour. The necrotic area was curetted and the beads were implanted through core tract in 9 hips (Steinberg IIc in 5 hips and IVc in 4 hips which involved greater than 30% of whole head; JIC classification C1 in 4 hips, and C2 in 5 hips which involved weight bearing area). The tract was blocked with a CMP rod. The age of patients ranged from 16 to 37. Associated factors were; steroid in 4, idiopathic in 3, alcoholic in 1 and traumatic in 1 hip, respectively. Kerboul combined necrotic angle was more than 200° in all hips. We compared preoperative and annual radiographs and MRI images to check dome depression of femoral head and signal change of osteonecrotic area. Follow-up period ranged from 8 to 14 years. Two IIc lesions progressed and were converted to THA at two and six years postoperatively. We could get clinical and radiographic success in 7 hips (78%). Follow-up radiographs and MRI showed partial or nearly complete regeneration of necrotic bone, prevention of collapse, and reduction in necrotic lesion. This can be a good strategy for bone regeneration of unmet need as in a human model.
Obovatol inhibits receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclastogenesis and prevents inflammatory bone loss in mice Adult skeletal mass and integrity are maintained by balancing osteoclast-mediated bone resorption and osteoblast-induced bone formation during bone remodeling. Abnormal increases in osteoclastic bone resorption can lead to excessive bone destruction as observed in osteoporosis, rheumatoid arthritis, and metastatic cancers Therefore, Modulation of osteoclast formation and function is a promising strategy for the treatment of bone-destructive diseases. To search for compounds that inhibit osteoclast formation, we tested the effect of obovatol, a natural product isolated from the medicinal plant Summary Statement
Introduction
Cancer-induced bone diseases are often associated with increased bone resorption and pathological fractures. In recent years, osteoprotective agents such as bisphosphonates have been studied extensively and have been shown to inhibit cancer-related bone resorption in experimental and clinical studies. The third-generation bisphosphonate, ibandronate (BM 21.0955), is a potent compound for controlling tumour osteolysis and hypercalcaemia in rats bearing Walker 256 carcinosarcoma. We have studied the effect of ibandronate given as an interventional treatment on bone strength and bone loss after the onset of tumour growth in bone. Our results suggest that it is capable of preserving bone quality in rats bearing Walker 256 carcinosarcoma cells. Since other bisphosphonates have produced comparable results in man after their success in the Walker 256 animal models our findings suggest that ibandronate may be a powerful treatment for maintaining skeletal integrity in patients with metastatic bone disease.
