Epidemiological study of intraosseous lesions of the stomatognathic or maxillomandibular complex diagnosed by a Reference Centre in Brazil from 2006–2017

This epidemiological study was designed to find out the incidence and factors associated with the occurrence of intraosseous lesions diagnosed at a Reference Centre in Brazil. We included all patients diagnosed with intraosseous lesions (cyst, tumour, bone-associated lesion, and periapical disease) during the period 2006–2017, and analysed the association between some sociodemographic and clinical variables and the types of lesion. There was a total of 290 intraosseous lesions, the most common being odontogenic cysts. There was a significant association between age and odontogenic tumours (p = 0.001). In relation to the histopathological diagnosis, root cysts were the most common (n = 57), followed by dentigerous cysts (n = 26). The lesions studied were seen most often in women between the second and fourth decades of life, odontogenic cysts being the most common type found. We know of few publications of similar epidemiological work, either in Brazil or in the rest of the world, so we suggest that more such studies are made.     

驱动基因在肺癌骨转移中的研究进展

骨是肺癌常见的血行转移部位之一，其发生率为30%~40%，好发于脊柱和躯干近端，包括脊柱、股骨、肋骨和胸骨等。肺癌骨转移患者中位生存期为6~10月，治疗后1年生存率为40%~50%。骨转移分子机制的研究对治疗具有重要的指导意义。研究显示肺癌原发灶和骨转移灶驱动基因表达存在异质性，然而肺癌驱动基因在肺癌骨转移中的作用以及对骨微环境的的影响机制尚不明确。本文就肺癌骨转移分子机制研究进展进行综述，着重对常见肺癌驱动基因在肺癌骨转移中的作用及对骨微环境的影响进行阐述。     

Calcium and vitamin D supplementation and loss of bone mineral density in women undergoing breast cancer therapy

An unintended consequence of breast cancer therapies is an increased risk of osteoporosis due to accelerated bone loss. We conducted a systematic review of calcium and/or vitamin D (Ca ± D) supplementation trials for maintaining bone mineral density (BMD) in women with breast cancer using the “before–after” data from the Ca ± D supplemented comparison group of trials evaluating the effect of drugs such as bisphosphonates on BMD. Whether Ca ± D supplements increase BMD in women undergoing breast cancer therapy has never been tested against an unsupplemented control group. However, results from 16 trials indicate that the Ca ± D doses tested (500–1500 mg calcium; 200–1000 IU vitamin D) were inadequate to prevent BMD loss in these women. Cardiovascular disease is the main cause of mortality in women with breast cancer. Because calcium supplements may increase cardiovascular disease risk, future trials should evaluate the safety and efficacy of Ca ± D supplementation in women undergoing breast cancer therapy.     

Investigating the Effects of Motion Streaks on pQCT-Derived Leg Muscle Density and Its Association With Fractures

Lower peripheral quantitative computed tomography (pQCT)-derived leg muscle density has been associated with fragility fractures in postmenopausal women. Limb movement during image acquisition may result in motion streaks in muscle that could dilute this relationship. This cross-sectional study examined a subset of women from the Canadian Multicentre Osteoporosis Study. pQCT leg scans were qualitatively graded (1–5) for motion severity. Muscle and motion streak were segmented using semi-automated (watershed) and fully automated (threshold-based) methods, computing area, and density. Binary logistic regression evaluated odds ratios (ORs) for fragility or all-cause fractures related to each of these measures with covariate adjustment. Among the 223 women examined (mean age: 72.7?±?7.1 years, body mass index: 26.30?±?4.97?kg/m²), muscle density was significantly lower after removing motion (p?<?0.001) for both methods. Motion streak areas segmented using the semi-automated method correlated better with visual motion grades (rho?=?0.90, p?<?0.01) compared to the fully automated method (rho?=?0.65, p?<?0.01). Although the analysis-reanalysis precision of motion streak area segmentation using the semi-automated method is above 5% error (6.44%), motion-corrected muscle density measures remained well within 2% analytical error. The effect of motion-correction on strengthening the association between muscle density and fragility fractures was significant when motion grade was?≥3 (p interaction <0.05). This observation was most dramatic for the semi-automated algorithm (OR: 1.62 [0.82,3.17] before to 2.19 [1.05,4.59] after correction). Although muscle density showed an overall association with all-cause fractures (OR: 1.49 [1.05,2.12]), the effect of motion-correction was again, most impactful within individuals with scans showing grade 3 or above motion. Correcting for motion in pQCT leg scans strengthened the relationship between muscle density and fragility fractures, particularly in scans with motion grades of 3 or above. Motion streaks are not confounders to the relationship between pQCT-derived leg muscle density and fractures, but may introduce heterogeneity in muscle density measurements, rendering associations with fractures to be weaker.     

In vitro cultivation of rat bone marrow mesenchymal stem cells and establishment of pEGFP/Ang-1 transfection method

ObjectiveTo obtain the bone marrow mesenchymal stem cells (BMSCs), complete phenotypic identification and successfully transfect rat BMSCs by recombinant plasmid pEGFP/Ang-1.MethodsBMSCs were isolated from bone marrow using density gradient centrifugation method and adherence screening method, and purified. Then the recombinant plasmid pEGFP/Ang-1 was used to transfect BMSCs and the positive clones were obtained by the screen of G418 and observed under light microscopy inversely. Green fluorescent exhibited by protein was enhanced to measure the change time of the expression amount of Ang-1.ResultsBMSCs cell lines were obtained successfully by adherence screening method and density gradient centrifugation. Ang-1 recombinant plasmid was transfected smoothly into rat BMSCs, which can express Ang-1 for 3 d and decreased after 7 d.ConclusionsAdherence screening method and density gradient centrifugation can be effective methods to obtain BMSCs with high purity and rapid proliferation. Besides, the expression of transfected recombinant plasmid pEGFP/Ang-1 in rat BMSCs is satisfactory.