BackgroundHigh strength porous titanium implants are widely used for the reconstruction of craniofacial defects because of their similar mechanical properties to those of bone. The recent introduction of electron beam melting (EBM) technique allows a direct digitally enabled fabrication of patient specific porous titanium implants, whereas both their in vitro and in vivo biological performance need further investigation.MethodsIn the present study, we fabricated porous Ti6Al4V implants with controlled porous structure by EBM process, analyzed their mechanical properties, and conducted the surface modification with biomimetic approach. The bioactivities of EBM porous titanium in vitro and in vivo were evaluated between implants with and without biomimetic apatite coating.ResultsThe physical property of the porous implants, containing the compressive strength being 163 - 286 MPa and the Young’s modulus being 14.5–38.5 GPa, is similar to cortical bone. The in vitro culture of osteoblasts on the porous Ti6Al4V implants has shown a favorable circumstance for cell attachment and proliferation as well as cell morphology and spreading, which were comparable with the implants coating with bone-like apatite. In vivo, histological analysis has obtained a rapid ingrowth of bone tissue from calvarial margins toward the center of bone defect in 12 weeks. We observed similar increasing rate of bone ingrowth and percentage of bone formation within coated and uncoated implants, all of which achieved a successful bridging of the defect in 12 weeks after the implantation.ConclusionsThis study demonstrated that the EBM porous Ti6Al4V implant not only reduced the stress-shielding but also exerted appropriate osteoconductive properties, as well as the apatite coated group. The results opened up the possibility of using purely porous titanium alloy scaffolds to reconstruct specific bone defects in the maxillofacial and orthopedic fields.

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<b><i>Background and Objectives:</i></b> Few studies have investigated the bidirectional relationship between disability and multimorbidity, which are common conditions among the older population. Based on the data from the China Health and Retirement Longitudinal Study (CHARLS) and the Survey of Health, Ageing and Retirement in Europe (SHARE), we aimed to investigate the bidirectional relationship between disability and multimorbidity. <b><i>Methods:</i></b> The activities of daily living (ADLs) and the instrumental activities of daily living (IADLs) scales were used to measure disability. In stage I, we used multinomial logistic regression to assess the longitudinal association between ADL/IADL disability and follow-up multimorbidity. In stage II, binary logistic regression was used to evaluate the multimorbidity effect on future disability. <b><i>Results:</i></b> Compared with those free of disability, people with disability possessed ascending risks for developing an increasing number of diseases. For ADL disability, the odds ratio (OR) (95% confidence interval [CI]) values of developing ≥4 diseases were 4.10 (2.58, 6.51) and 6.59 (4.54, 9.56) in CHARLS and SHARE; for IADL disability, the OR (95% CI) values were 2.55 (1.69, 3.84) and 4.85 (3.51, 6.70) in CHARLS and SHARE. Meanwhile, the number of diseases at baseline was associated, in a dose-response manner, with future disability. Compared with those without chronic diseases, participants carrying ≥4 diseases had OR (95% CI) values of 4.82 (3.73, 6.21)/4.66 (3.65, 5.95) in CHARLS and 3.19 (2.59, 3.94)/3.28 (2.71, 3.98) in SHARE for developing ADL/IADL disability. <b><i>Conclusion:</i></b> The consistent findings across 2 national longitudinal studies supported a strong bidirectional association between disability and multimorbidity among middle-aged and elderly adults. Thus, tailored interventions should be taken to prevent the mutual development of disability and multimorbidity.

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Mining and smelting activities engender soil contamination by metals severely. A field survey was conducted to investigate the present situation and health risk of heavy metals (Cd, Pb, Zn, Cu, Cr, As, and Hg) in soils and vegetables in the surrounding area of an 80-year-old zinc smelter in northeastern China. Soil pH, organic matter (SOM), and cation exchange capacity (CEC) were determined, and their relations with heavy metal contents in edible parts of vegetables were analyzed. Results showed that the smelting had led to the significant contamination of the local soils by Cd and Zn, with average concentrations of 3.88 and 403.89 mg kg, respectively. Concentrations of Cd and Zn in greenhouse soils were much lower than those in open farmland soils. Cd concentrations in vegetable edible parts exceeded the permissible limits severely, while other metal concentrations were much lower than the corresponding standards. Leaf and root vegetables had higher concentrations and bioaccumulation factors (BCFs) of Cd than fruit vegetables. Hazard quotient and hazard index showed that cadmium is imposing a health risk to local residents via vegetable consumption. Cd uptake of some vegetables can be predicted by empirical models with the following parameters: soil pH, SOM, CEC, Zn concentrations, and Cd concentrations. Vegetables such as cabbage, Chinese cabbage, tomato, cucumber, and green bean were screened out as being suitable to grow in the studied area.