Aim
To investigate the influence of mineral trioxide aggregate (MTA) on angiogenesis of primary human dental pulp cells (hDPCs) via the MAPK pathway, in particular p38.
Methodology
Human dental pulp ...cells were cultured with MTA to angiogenesis, after which cell viability, ion concentration, osmolality, NO secretion, the von Willebrand factor (vWF) and angiopoietin‐1 (Ang‐1) protein expression were examined. PrestoBlue® was used for evaluating the proliferation of hDPCs. An enzyme‐linked immunosorbent assay was employed to determine vWF and Ang‐1 protein secretion in hDPCs cultured on MTA and the control. Cells cultured on the tissue culture plate without the cement were used as the control. The t‐test was used to evaluate the significance of the differences between the mean values.
Results
Mineral trioxide aggregate elicited a significant (P < 0.05) increased viability compared with the control (15%, 16% and 13% on days 1, 3 and 5 of cell seeding, respectively). MTA consumed calcium and phosphate ions, and released more Si ions in the medium. MTA significantly (P < 0.05) increased the osmolality of the medium to 313, 328 and 341 mOsm kg−1 after 1, 3 and 5 days, respectively. P38 was activated through phosphorylation, and the phosphorylation kinase was investigated in the cell system after being cultured with MTA. Expression levels for Ang‐1 and vWF in hDPCs on MTA were higher than those of the MTA + p38 inhibitor (SB203580) group (P < 0.05) at all of the time‐points.
Conclusions
Mineral trioxide aggregate was able to activate the p38 pathway in hDPCs cultured in vitro. Moreover, Si increased the osmolality required to facilitate the angiogenic differentiation of hDPCs via the p38 signalling pathway. When the p38 pathway was blocked by SB203580, the angiogenic‐dependent protein secretion decreased. These findings verify that the p38 pathway plays a key role in regulating the angiogenic behaviour of hDPCs cultured on MTA.
There is accumulating evidence for the efficacy of nonpharmacological multimodal stimulation interventions in maintaining cognition and improving quality of life in people with mild-to-moderate ...dementia. However, the complex nature of these interventions limits their application in practice and research. We report here the design and development of a culturally appropriate framework, the Six Arts, to guide delivery of multimodal interventions in a Chinese community.
The Six Arts are a core set of Confucian philosophy comprising 6 disciplines of rites, music, archery, charioteering, literacy, and numeracy. They correspond to major mind-body functional domains of social functioning; music and rhythm; visuospatial and fine motor skills; kinesthetic and gross motor skills; language and verbal skills; and executive function. Using Six Arts as a framework, we mapped theoretical principles and evidence-based nonpharmacological interventions of cognitive stimulation, physical exercise, and social activities against the 6 functional domains. From 2011, we field-tested the use of Six Arts in structuring intervention programs in 263 people in a dementia day center in Hong Kong.
The Six Arts was operationalized through the development of an intervention activity database, a scoring system for intensity level, and a service delivery model for application in dementia day centers.
Six Arts can be used as framework for structuring nonpharmacological group intervention programs in dementia day center in a metropolitan Chinese city. Its cultural appropriateness may facilitate communication and shared decision making with families with dementia in communities influenced by Confucian philosophy.
Aim
To examine the effects of mineral trioxide aggregate (MTA)/fibroblast growth factor‐2 (FGF‐2) on material properties and in vitro human dental pulp cell (hDPCs) behaviour.
Methodology
The setting ...time and diametral tensile strength (DTS) of MTA and MTA/FGF‐2 were measured. The structure of specimens before and after soaking in DMEM was examined under a scanning electron microscope. Alamar Blue was used for evaluating hDPCs proliferation. An enzyme‐linked immunosorbent assay was employed to determine ALP and osteocalcin (OC) expression in hDPCs cultured on cements. The effect of small interfering RNA (siRNA) transfection targeting fibroblast growth factor receptor (FGFR) was also evaluated. One‐way analysis of variance was used to evaluate the significance of the differences between the mean values.
Results
Setting time and DTS data were not found to be significant (P > 0.05) between MTA with and without FGF‐2. Cell proliferation and differentiation increased significantly (P < 0.05) with FGF‐2 mixed MTA. After siRNA transfection with FGFR, the proliferation and differentiation behaviour of the hDPCs appreciably decreased when cultured on an MTA/FGF‐2 composite. In contrast, no significant amounts (P > 0.05) of ALP and OC were secreted by hDPCs seeded on MTA.
Conclusions
Mineral trioxide aggregate with FGF‐2 content enhanced the higher expression of hDPCs proliferation and osteogenic differentiation as compared to pure MTA cement.
Shie MY, Chang HC, Ding SJ. Effects of altering the Si/Ca molar ratio of a calcium silicate cement on in vitro cell attachment. International Endodontic Journal, 45, 337–345, 2012.
Aim To examine ...the effects of altering the Si/Ca molar ratio (6 : 4, 5 : 5, and 4 : 6) of a quick‐setting calcium silicate cement on in vitro cell attachment.
Methodology Working time and setting time of three different calcium silicate cements were measured. Alamar Blue was used for real‐time and repeated monitoring of cell attachment and proliferation. The Si and Ca ion concentrations of the cell culture medium in the presence of three different calcium silicate cements seeded with MG63 cells were measured. Kinetic immunofluorescent staining of MG63 cells was performed during cell attachment and spreading. Reverse transcription‐polymerase chain reaction was employed to determine gene expression in MG63 cells cultured on the cements. One‐way analysis of variance was used to evaluate the significance of the differences between the mean values.
Results The working time (4–7 min) and setting time (17–24 min) of the cements were shortened with an increase in the Ca content of the calcium silicate powders after mixing the powder with water. In contrast, the higher the Si content in the cement, the more the MG63 cells attached to the cement at all culture time‐points, accompanying by the formation of more obvious actin stress fibres. Cell proliferation and differentiation increased significantly (P < 0.05) with an increase in the Si content of the calcium silicate cements. Si ion concentration of the culture medium increased significantly (P < 0.05) with increasing cement Si content and culture time‐points.
Conclusions The higher Si content cement enhanced the higher expression of cell attachment, proliferation and differentiation as compared to the lower Si content cement.
Aim To present our experience of the clinical management of spontaneous isolated dissection of superior mesenteric artery (SIDSMA) and analyse the clinical features, imaging findings, and treatment ...outcomes. Materials and methods In this retrospective study, eight consecutive patients with symptomatic SIDSMA were treated in Chang Gung Memorial Hospital between April 2007 and April 2010; among these patients, six underwent endovascular stent placement. The clinical manifestations, imaging findings, endovascular stent placement outcome, and follow-up results of the patients were retrospectively analysed. Results Eight patients were diagnosed with SIDSMA by contrast-enhanced computer tomography. One patient died due to comorbidity before angiography. Six patients underwent percutaneous endovascular stent placement in the superior mesenteric artery (SMA): four patients with bare stents and two with stent grafts. Because it was not appropriate to perform stent implantation in the remaining patient, he received only conservative treatment. All seven patients had an uneventful recovery and the follow-up period was 16 month, ranging from 1 to 35 months. Conclusion For patients with symptomatic SIDSMA, endovascular repair is a feasible treatment choice with a high success rate and good clinical outcome.
Chen CC, Shie MY, Ding SJ. Human dental pulp cell responses to new calcium silicate‐based endodontic materials. International Endodontic Journal, 44, 836–842, 2011.
Aim To evaluate human dental pulp ...cell responses to radiopaque dicalcium silicate cement and white‐coloured mineral trioxide aggregate (WMTA).
Methodology Flow cytometry was employed to quantify the phase percentage of pulp cell cycle. Alamar Blue was used for real‐time and repeated monitoring of cell proliferation. Reverse transcription‐polymerase chain reaction was performed to determine gene expression in pulp cells cultured on the cements.
Results The cells cultured on the radiopaque dicalcium silicate cement had similar S and G2 phases in the cell cycle and proliferation to WMTA at all culture times. In addition, the two materials presented the same evolution with similar values in interleukin‐1, inducible nitric oxide synthase, alkaline phosphatase, osteocalcin and bone sialoprotein gene expression at all culture times.
Conclusions The dental pulp cell responses to radiopaque dicalcium silicate cement were similar to those reported for WMTA in terms of cell cycle, proliferation, immunocompatibility and osteogenic differentiation.
To determine whether patients receiving directly observed treatment (DOT) had lower all-cause mortality than those treated with self-administered treatment (SAT) and to identify factors associated ...with mortality among tuberculosis (TB) patients.
All TB patients in Taipei, Taiwan, diagnosed between 2006 and 2008 were included in a retrospective cohort study.
Among 3624 TB patients, 45.5% received DOT, which was disproportionately offered to older patients and those with more underlying illness and severe TB disease. After controlling for patients' sociodemographic factors, clinical findings and underlying comorbidities, the odds of death were 40% lower (aOR 0.60, 95%CI 0.5-0.8) among patients treated with DOT than those on SAT. After adjusting for DOT, independent predictors of death included non-Taiwan birth, increasing age, male, unemployment, end-stage renal disease requiring dialysis, malignancy, acid-fast bacilli smear positivity and pleural effusion.
DOT was associated with lower all-cause mortality after controlling for confounding factors. DOT should be expanded in Taiwan to improve critical treatment outcomes among TB patients.
Gradient porous materials are gradually developed for some biomedical implants such as mandible and vertebrae to meet the varied Young's modulus due to serious bone density variation and thus to ...avoid serious stress shielding effect. In this study, different designs of gradient porous materials are fabricated by additive manufacturing 3D printing via the electron beam melting (EBM) method, and the mechanical properties are examined. The first attempt is to examine the size variation of porosity gradient region, with gradual transition region from 0 to 8 mm in height from the lower 70% porosity region to the higher 90% porosity region. The gradient transition has pronounced impact on the mechanical response improvement of porous EBM foams. The second attempt is to explore the effect of porosity variation and the interface discontinuity degree, or the degree of strut overlapping. The foam mechanical properties are governed mainly by the mechanical properties of the higher porosity portion and the mismatch on the interface; the latter degree of mismatch (or the degree of strut overlapping) plays a more dominant role. By re-designing to fulfill complete continuity with no mismatch of the struts on the interface, significant improvement of the mechanical properties can be achieved.
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•Gradient and sharp porous samples with different mismatch degrees are designed by CAD.•The additive manufacturing electron beam melting method is adopted.•The detailed mechanical and failure responses are systematically characterized.•The mechanical strength of gradient porous specimens with transition region is dominated by high porosity region.•The degree of interface mismatch plays the dominant role for mechanical response in the sharp porous samples.
Three systematically functionalized pyrrolide ligands were prepared via the coupling of methyl vinyl ketone and the respective carbaldehyde reagents, followed by treatment of the pre‐formed ...dicarbonyl compounds with (NH4)2CO3 in order to generate the required pyrrole fragment. These ligands readily reacted with the boron reagent BPh3 to afford the complexes (pyro)BPh2 (2a), (noro)BPh2 (2b), and (xaro)BPh2 (2c), where (pyro)H, (noro)H, and (xaro)H represents the 2‐pyridyl, 2‐quinolinyl, and 2‐quinoxalinyl pyrrole groups, respectively. Complexes 2a–2c give stable solutions in air, and show strong photoluminescence with emission peak maxima located at 490 nm, 510 nm, and 575 nm, respectively. Calculations based upon time‐dependent density function theory (TDDFT) show that the S1 state in these complexes is attributed to an allowed (π‐symmetry) → π* (π‐symmetry) transition located at the chelating pyrrolide moieties. Electroluminescence (EL) devices based on 2c were fabricated. The EL emission from 2c as the host‐emitter, with the emission peak maximum shifted to 580 nm, was observed when BCP was used as the hole blocking material. This device produces saturated red‐orange light‐emission at an onset voltage of 8 V and a maximum brightness of 5000 cd m–2 at a driving voltage of 15 V; the external quantum yield is estimated to be 0.5 %.
Three highly emissive BPh2 complexes with 2‐pyridyl‐, 2‐quinolinyl‐, and 2‐quinoxalinyl‐pyrrolide chelates have been synthesized. They exhibit distinctive variations of emission color spanning from greenish blue to red orange (see Figure). A rational explanation for these color changes is provided by time‐dependent density functional theory calculations.
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