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Aim: To analyse in vitro changes in ion release and biological properties of Endocem‐MTA (Maruchi, Wonju, Korea) and NeoMTA‐Plus (Avalon Biomed Inc, Bradenton, FL, USA) exposed to acidic or neutral environment on human dental periodontal ligament stem cells (hPDLSCs). Methodology: Cell viability and wound healing assays were performed using eluates of each material. Cell death and changes in phenotype induced by the set endodontic sealer eluates were evaluated through flow cytometry. To evaluate cell attachment to the different materials, hPDLSCs were directly seeded onto the material surfaces and analysed by scanning electron microscopy. The chemical composition of the materials was determined by energy‐dispersive X‐ray (EDX), and ion release was evaluated by inductively coupled plasma‐mass spectrometry. Statistical analysis was performed with analysis of variance and a Bonferroni or Tukey post‐test (α < 0.05). Results: The MTT assay revealed non‐cytotoxic effects of NeoMTA‐Plus and Endocem‐MTA at pH 5.2 and 7.4. However, there were minor differences compared with the control, especially at pH 5.2, where both materials were associated with significantly greater cell viability (P < 0.05). In both environments, the materials stimulated hPDLSCs to migrate. hPDLSCs were attached to the bioactive cements, with multiple prolongations proliferated on the surface of the samples. Moreover, there were no changes to cell phenotype or apoptosis/necrosis rates, indicating that the acidic environment did not induce cell death. Prismatic crystalline structures were seen on the surface of the cements exposed to butyric acid and EDX analysis identified a marked peak of Ca2+ from NeoMTA‐Plus and Endocem‐MTA in acidic and physiological environments. Conclusions: An acidic environment favoured the release of Ca2+ ions from both bioactive cements, and the cytotoxicity of these bioactive cements was low in both environments studied. [ABSTRACT FROM AUTHOR]

Aims To investigate the cytotoxicity and bioactivity of several pulpotomy materials: Biodentine (Septodont, Saint-Maur-des-Fosses, France) MTA (Angelus, Londrina, PR, Brazil), Theracal LC (Bisco Inc., Schamburg, IL, USA) and IRM (Dentsply DeTrey GmbH, Konstanz, Germany), after contact with stem cells isolated from human exfoliated primary teeth ( SHEDs). Methodology SHEDs were cultured in the presence of the eluates of various pulpotomy materials for 24, 48 and 72 h. Cell viability was determined by mitochondrial dehydrogenase enzymatic ( MTT) assay. Apoptosis and changes in cell phenotype were evaluated by flow cytometry. Also, an in vitro scratch wound-healing assay was used to determine their effects on cell migration. To assess cell morphology and attachment to the different pulpotomy materials, SHEDs were directly seeded onto the material surfaces and analysed by scanning electron microscopy ( SEM). Finally, the deposition of a calcified matrix in presence of these materials was verified by Alizarin Red staining. Statistical analysis was performed with analysis of variance and Bonferroni or Tukey post-test (α = 0.05). Results Cell viability in the presence of Biodentine eluates was significantly higher to that obtained using complete medium alone (control; P < 0.01) and was also significantly higher than using MTA Angelus from 48 h of incubation ( P < 0.01). However, Theracal LC and IRM were associated with low rates of cell viability ( P < 0.001). Similar results were obtained in an apoptosis assay. In addition, SHEDs maintained their mesenchymal phenotype in all conditions although their capacity to migrate was higher in the presence of Biodentine. SEM studies revealed a suitable proliferation rate, cell spreading and attachment, especially when using Biodentine and MTA Angelus discs. Finally, Biodentine eluates significantly induced calcified matrix deposition from 7 days of culture ( P < 0.01). Conclusions Biodentine exhibited better cytocompatibility and bioactivity than MTA Angelus, Theracal LC and IRM. [ABSTRACT FROM AUTHOR]

Aim To evaluate the biological effects in vitro of MTA-Angelus (MTA-Ang; Angelus, Londrina, PR, Brazil), MTA Repair HP (MTA-HP; Angelus) and NeoMTA Plus (NeoMTA-P; Avalon Biomed Inc, Bradenton, FL, USA) on human dental pulp stem cells ( hDPSCs). Methodology Cell viability and cell migration assays were performed using eluates of each material. To evaluate cell morphology and cell attachment to the different materials, hDPSCs were directly seeded onto the material surfaces and analysed by immunocytofluorescence and scanning electron microscopy, respectively. The chemical composition of the materials was determined by energy-dispersive X-ray (EDX), and eluates were analysed by inductively coupled plasma-mass spectrometry (ICP-MS). Statistical analysis was performed with the analysis of variance and Bonferroni or Tukey post-test (α < 0.05). Results Undiluted MTA-Ang, MTA-HP and NeoMTA-P displayed a significant increase in cell viability greater than that obtained using complete medium alone (control) (* P < 0.05; ** P < 0.01; *** P < 0.001). Moreover, a cell migration assay revealed cell migration rates after incubation with extracts of MTA-Ang, MTA-HP and NeoMTA-P that were similar to levels obtained in the control group. In addition, stretched cytoskeletal F-actin fibres were detected in the cells treated with the three material extracts. SEM studies revealed a high degree of cell proliferation and attachment on all three materials. EDX analysis demonstrated similar weight percentages of C, O and Ca in all three materials, whilst other elements such as Al, Si and S were also found. Conclusions MTA-Ang, MTA-HP and NeoMTA-P were associated with biological effects on hDPSCs in terms of cell proliferation, morphology, migration and attachment. [ABSTRACT FROM AUTHOR]

Aim To investigate in vitro the cytocompatibility of the calcium silicate-containing endodontic sealers MTA Fillapex and TotalFill BC Sealer on human periodontal ligament stem cells ( hPDLSCs) by assaying their biological responses and compare them with that observed when using an epoxy resin-based sealer ( AH Plus). Methodology Specimens from the three different endodontic sealers were eluated with culture medium for 24 h. The cytotoxicity of these eluates was evaluated using the MTT assay. In addition, an in vitro scratch wound healing model was used to determine their effects on cell migration. Cell adhesion to collagen type I after treatment with the different sealer eluates was also measured, whereas cytotoxicity was determined using the DNA-specific fluorochrome Hoechst 33342. Finally, to assess cell morphology and attachment to the different sealers, hPDLSCs were directly seeded onto the material surfaces and analysed by scanning electron microscopy ( SEM). One-way analysis of variance ( anova) followed by a Bonferroni post-test were performed ( P < 0.05). Results hPDLSCs exposed to different dilutions of TotalFill BC Sealer eluates had significantly higher cell proliferation compared with that observed when cells were treated with AH Plus and MTA Fillapex eluates ( P < 0.001). In addition, TotalFill eluates were associated with significantly increased cell adhesion to collagen type I and migration of hPDLSCs in a concentration-dependent manner than displayed after treatment with MTA Fillapex or AH Plus eluates ( P < 0.001). Moreover, TotalFill BC Sealer-induced cytotoxicity was significantly lower than observed using AH Plus and MTA Fillapex eluates ( P < 0.001). Finally, SEM studies revealed suitable proliferation, cell spreading and attachment, especially when using TotalFill BC Sealer discs. Conclusion TotalFill BC Sealer exhibited a higher cytocompatibility than AH Plus and MTA Fillapex. Further investigations using in vivo animal models are required to validate the potential biological responses of TotalFill BC Sealer on hPDLSCs. [ABSTRACT FROM AUTHOR]

Rodríguez-Lozano FJ, Bueno C, Insausti CL, Meseguer L, Ramírez MC, Blanquer M, Marín N, Martínez S, Moraleda JM. Mesenchymal stem cells derived from dental tissues. International Endodontic Journal, 44, 800-806, 2011. Abstract Regeneration of tissues occurs naturally due to the existence of stem cells with the capacity to self-regenerate and differentiate; however, regenerative capacity decreases with age, and in many cases, regeneration is not sufficient to repair the damage produced by degenerative, ischaemic, inflammatory, or tumour-based diseases. In the last decade, advances have been made in the understanding of stem cells, the genes that control the alternative fates of quiescence and differentiation, and the niches that provide specific signals that modulate cell fate decisions. Embryonic stem-cell research is shedding light on the secrets of development. Adult stem cells (AS cells) are available from several sources. Bone marrow and connective tissue have been used in preliminary clinical trials for regenerative therapy. Recently, several types of AS cells have been isolated from teeth, including dental pulp stem cells, stem cells from human exfoliated deciduous teeth, periodontal ligament stem cells, dental follicle progenitor stem cells and stem cells from apical papilla. Preliminary data suggest that these cells have the capacity to differentiate into osteoblasts, adipocytes, chondrocytes and neural cells. If confirmed, these data would support the use of these cells, which are easily obtained from extracted teeth, in dental therapies, including in regenerative endodontics, providing a new therapeutic modality. [ABSTRACT FROM AUTHOR]

Alloimmune incompatibility in allo-geneic stem cell transplantation (ASCT), pregnancy, and blood transfusion might trigger an immune response with clinical consequences. Human PLT antigens (HPAs), which play a significant role in pregnancy or blood transfusion-associated alloimmune thrombocytopenia, are also expressed on the surface of tissues affected by GVHD. Thus, HPA mismatch in HLA-identical ASCT could play a potential role in PLT engraftment and GVHD. We studied the HPA-1, -2, and -5 genotypes in Caucasian donors and patients involved in 77 HLA-identical ASCTs. We evaluated the association of HPA compatibility with clinical outcome, analyzing the relevance of host-versus-donor HPA incompatibility in PLT engraftment and donor-versus-host HPA incompatibility in GVHD. PLT engraftment and transfusion require-ments were similar in HPA-compatible and HPA-incompatible ASCT. Cases with severe thrombocytopenia or significant delayed PLT engraftment did not display host-versus-donor HPA incompatibility. Moreover, the incidence of GVHD did not correlate with HPA compatibility. Our results support no role for these antigens in immune complications of ASCT: PLT engraftment, requirement of PLT transfusions, and GVHD. [ABSTRACT FROM AUTHOR]

The article discusses bone-anchored hearing aid (BAHA) procedure in children. Topics discussed include localization of titanium cover screw, method to locate the screw and ultrasound technique for localization. Other topics such as palpation of the screw through scalp tissue is also discussed. An ultrasound image of BAHA cover screw is presented.

To assess the influence of graft-versus-host disease (GVHD) on the outcome of patients with advanced haematological malignancies (AHM) who received a primary, unmodified allogeneic peripheral blood progenitor cells transplant (allo-PBT) from a human leucocyte antigen (HLA) identical sibling donor, we analysed 136 patients with myeloid neoplasms (n = 70) or lymphoproliferative disorders (n = 66), transplanted at 19 Spanish institutions. Median age was 35 years (range 1-61). The cumulative incidence of relapse for all patients was 34% (95% CI, 26-42%), 41% (95% CI, 33-49) for patients without GVHD and 14% (95% CI, 3-25) (P = 0.001) for patients with acute and chronic GVHD. After a median follow-up of 11 months (range 2-49), 60 (44%) patients remained alive with an actuarial probability of overall survival and disease-free survival (DFS) at 30 months of 31% (95% CI, 21-41%) and 28% (95% CI, 17-39%) respectively. In patients surviving > 100 d, the low incidence of relapse in those with acute and chronic GVHD led to a DFS of 57% (95% CI, 38-76%) compared with a DFS of 34% (95% CI, 17-51%) in the remaining patients (P = 0.03). Our results indicate a reduced incidence of relapse for patients with AHM receiving an unmodified allo-PBT and developing acute and chronic GVHD, which results in an improved DFS.

We have retrospectively analysed 344 multiple myeloma (MM) patients (202 de novo patients) treated in a non-uniform way in whom high-dose therapy and autologous stem cell transplantation (ASCT) response was simultaneously measured by both electrophoresis (EP) and immunofixation (IF). Patients in complete remission (CR) by EP were further subclassified as CR1 when IF was negative and CR2 when it remained positive. Partial responders (PR) were also subclassified as PR1 (very good PR, > 90% reduction in M-component) or PR2 (50-90% reduction). CR1 patients showed a significantly better event-free survival (EFS) [35% at 5 years, 95% confidence interval (CI) 17-53, median 46 months] and overall survival (OS) (72% at 5 years, CI 57-86, median not reached) compared with any other response group (univariate comparison P < 0.00000 to P = 0. 004). In contrast, comparison of CR2 with PR1 and with PR2 did not define different prognostic subgroups (median EFS 30, 30 and 26 months respectively, P = 0.6; median survival 56, 44 and 42 months respectively, P = 0.5). The non-responding patients had the worst outcome (5-year OS 8%, median 7 months). Multivariate analysis confirmed both the absence of differences among CR2, PR1 and PR2 and the highly discriminatory prognostic capacity of a three-category classification: (i) CR1 (ii) CR2 + PR1 + PR2, and (iii) non-response (EFS P < 0.00000; OS P < 0.00000; both Cox models P < 0.00000). In the logistic regression analysis, the factors significantly associated with failure to achieve CR1 were the use of two or more up-front chemotherapy lines, status of non-response pre-ASCT and inclusion of total body irradiation (TBI) in the preparative regimen. Tandem transplants or the use of multiple agents (busulphan and melphalan) in the preparative regimen resulted in a higher CR1 level; none of the biological factors explored influenced the possibility of achieving CR1. These results confirm that, in MM patients undergoing ASCT, achieving a negative IF identifies the patient subset with the best prognosis; accordingly, therapeutic strategies should be specifically designed to achieve negative IF.

High-dose chemoradiotherapy conditioning regimens for autologous stem cell transplantation (ASCT) are generally held to give similar results in multiple myeloma (MM), but no specific comparative study has been published. We addressed this issue by comparing the main high-dose chemoradiotherapy regimens used in the Spanish Registry. Patient cohorts included 315 cases treated with 200 mg/m2 melphalan (MEL200), 127 patients with 140 mg/m2 melphalan plus total body irradiation (MEL140 + TBI) and 121 cases with 12 mg/kg busulphan plus 140 mg/m2 melphalan (BUMEL). After ASCT, granulocyte and platelet recovery time was similar in all conditioning groups. There were no differences in transplant-related mortality. All regimens yielded a similar response in reference to pre-ASCT MM status, although BUMEL produced a slightly better overall response when compared with the other regimens (97% vs. 89% and 92%, P = 0.003). The 5-year overall survival (OS) with BUMEL was 47% [95% confidence interval (CI) 26-68] compared with 43% (CI 31-54) for MEL140 + TBI and 37% (CI: 18-56) for MEL200. The median survival for the BUMEL group was 64 months compared with 45 and 37 months for the MEL200 and MEL140 + TBI groups respectively. These differences were non-significant (P = 0.2). The median event-free survival (EFS) was better for BUMEL (32 months) than for MEL200 (22 months) or for MEL140 + TBI (20 months). The differences in EFS between BUMEL and the other conditioning regimens reached statistical significance (P = 0.01). Nevertheless, the adjusted multivariate analysis for OS and EFS revealed that the conditioning regimens had no independent prognostic value. We concluded that three different conditioning regimens, commonly used for ASCT in MM, have a similar antimyeloma effect. However, the trend for better results observed in our series with BUMEL requires a prospective trial.

A decrease of platelet agglutination induced by ristocetin has been described in cirrhotic patients. In order to investigate the relationship of such phenomenon with a putative defect on platelet membrane glycoprotein Ib, we have studied the quantitative and functional status of Gp Ib in eleven severe alcoholic cirrhotic patients, and the ability of their formalin-fixed platelets to agglutinate in the presence of normal plasma plus ristocetin. Interestingly, we found a significant decrease of immunoreactive GP Ib molecules (9,978 +/- 1,534 vs. 17,064 +/- 404 molecules per platelet) and ristocetin-dependent binding of vWF (9,113 +/- 1,338 vs. 13,992 +/- 1,968 molecules per platelet) (P < 0.01) in comparison to the levels found in a control group of healthy subjects. Immunoblotting analysis of platelet lysates confirmed the reduction of GP Ib level in cirrhotic patients, but showed no modification on the precipitation pattern of this glycoprotein. The ristocetin-induced platelet agglutination (light transmission %) was also significantly lower in patients with cirrhosis (48 +/- 7.6 vs. 92 +/- 3.6, P < 0.01), and correlated with the binding of normal vWF (r = 0.863, P = 0.0013). Patients with bleeding times longer than 7 min and/or clinical history of bleeding episodes showed the lowest values of platelet agglutination and GP Ib level. In conclusion, our present results indicate that liver cirrhosis is associated with a relevant decrease of functional GP Ib molecules on the platelet surface. This reduction might be related to the prolongation of bleeding time and to the bleeding diathesis observed in cirrhotic patients.