Influence of the Crystallization Firing Process on Marginal and Internal Adaptation of Silicate-based Glass-ceramic Inlays Fabricated With a CAD/CAM Chairside System.

OBJECTIVE: Computer-aided design/computer-aided manufacturing (CAD/CAM) systems are widely used in dental treatment. Clinicians can use chairside CAD/CAM technology, which has the advantage of being able to fabricate inlays on the same day. We aimed to evaluate the effects of crystallization firing processes, fabrication methods (one-step and two-step), and materials on marginal and internal adaptations of silicate-based glass-ceramic all-ceramic inlays fabricated with CAD/CAM chairside systems. METHODS: Ten artificial mandibular left first molars were prepared with standardized ceramic class II mesialocclusal (MO) inlay cavities. Optical impressions were obtained using CEREC Omnicam Ban. IPS e-max CAD (IE), (Ivoclar Vivadent, Schaan, Liechtenstein), Initial LiSi Block (LS) (Hongo, Bunkyoku, Tokyo, Japan), VITA Suprinity (SP), (Vita Zahnfabrick, Bad Säckingen, Germany), and Celtra Duo (CD) (Ivoclar Vivadent, Schaan, Liechtenstein) (n=10) were milled using CEREC MC XL (Bensheim, Germany). IE and SP were crystallization-fired using CEREC Speed Fire. The silicone replica technique was used for the measurement of internal (axial and pulpal walls) and marginal (cervical and occlusal edge) adaptations. The adaptations were measured using a thin layer of light-body polyvinyl siloxane impression material placed between the master tooth inlay preparation and restoration. Marginal and internal adaptations of IE, LS, SP, and CD were measured using a stereomicroscope (500×). For IE and SP, marginal and internal adaptations were measured before and after the crystallization firing process. Data analyses were conducted using one-way ANOVA and the Tukey test. For IE and SP, marginal and internal adaptations before and after the crystallization firing process were analyzed using the t-test. The significance level was set at α=0.05. RESULTS: One-way ANOVA revealed statistically significant differences in occlusal and cervical edge marginal adaptations among the material groups (p<0.001). The Tukey HSD test revealed a significant difference in marginal occlusal and cervical edge adaptations between LS and CD groups and IE and SP groups (p≤0.05). For IE and SP inlays, the t-test revealed a significant difference between occlusal and cervical edge adaptations before the crystallization firing process and those after the crystallization firing process, with the latter group showing a more significant discrepancy in adaptation than the former group (p≤0.05). CONCLUSIONS: Fabrication methods (one- and two-step) affected the marginal adaptation compatibility but not internal compatibility of MO inlays. The crystallization firing process affected the marginal adaptation of inlays using lithium silicate or lithium disilicate glass-ceramics. However, adaptation to the cavity was considered clinically acceptable for all materials.

Interaction between NUDT15 and ABCC4 variants enhances intolerability of 6-mercaptopurine in Japanese patients with childhood acute lymphoblastic leukemia.

6-Mercaptopurine (6-MP) is a main component of childhood acute lymphoblastic leukemia (ALL) treatment. Some candidate gene variants are associated with its toxicities, but the major variants and effects of combined variants remain unclear. We used Cox regression analysis to evaluate the time-dependent association between candidate variants and the cumulative incidence of 6-MP intolerability in 95 Japanese patients. The major risk factors for severe leukopenia were ABCC4 rs3765534, NUDT15 rs116855232 and rs186364861 in multi-covariate analysis (P<0.05). NUDT15 intermediate activity variant, that is, heterozygous rs116855232 or rs186364861 variant, and the ABCC4 rs3765534 variant showed leukopenia more frequently than either variant alone. All patients with both the intermediate activity NUDT15 variant and the ABCC4 rs3765534 variant suffered from leukopenia, and 57.1% patients required 50% protocol dose by day 168. These data indicate that NUDT15 and ABCC4 are major factors for 6-MP intolerability and that the interaction between these variants enhances intolerability to 6-MP.

Long-term outcome of 6-month maintenance chemotherapy for acute lymphoblastic leukemia in children.

In the treatment of childhood acute lymphoblastic leukemia (ALL), excess shortening of maintenance therapy resulted in high relapse rate, as shown by our previous trial, TCCSG L92-13, in which maintenance therapy was terminated at 1 year from initiation of treatment. In this study, we aimed to confirm the long-term outcome of L92-13, and to identify who can or cannot be cured by shorter duration of maintenance therapy. To obtain sentinel cytogenetics information that had been missed before, we performed genetic analysis with genomic microarray and target intron-capture sequencing from diagnostic bone marrow smear. Disease-free survival (DFS) at 10 years from the end of therapy was 66.0±2.8%. Females (n=138) had better DFS (74.6±3.7%) than males (n=142, 57.5±4.2%, P=0.002). Patients with TCF3-PBX1 (n=11) and ETV6-RUNX1 (n=16) had excellent DFS (90.9±8.7% and 93.8±6.1%, respectively), whereas high hyperdiploidy (n=23) was the most unfavorable subgroup, with 56.6±10.3% of DFS. Short duration of therapy can cure more than half of pediatric ALL, especially females, TCF3-PBX1 and ETV6-RUNX1. Our retrospective observations suggest a gender/karyotype inhomogeneity on the impact of brief therapy.

Characterization of pediatric Philadelphia-negative B-cell precursor acute lymphoblastic leukemia with kinase fusions in Japan.

Recent studies revealed that a substantial proportion of patients with high-risk B-cell precursor acute lymphoblastic leukemia (BCP-ALL) harbor fusions involving tyrosine kinase and cytokine receptors, such as ABL1, PDGFRB, JAK2 and CRLF2, which are targeted by tyrosine kinase inhibitors (TKIs). In the present study, transcriptome analysis or multiplex reverse transcriptase-PCR analysis of 373 BCP-ALL patients without recurrent genetic abnormalities identified 29 patients with kinase fusions. Clinically, male predominance (male/female: 22/7), older age at onset (mean age at onset: 8.8 years) and a high white blood cell count at diagnosis (mean: 94 200/µl) reflected the predominance of National Cancer Institute high-risk (NCI-HR) patients (NCI-standard risk/HR: 8/21). Genetic analysis identified three patients with ABL1 rearrangements, eight with PDGFRB rearrangements, two with JAK2 rearrangements, three with IgH-EPOR and one with NCOR1-LYN. Of the 14 patients with CRLF2 rearrangements, two harbored IgH-EPOR and PDGFRB rearrangements. IKZF1 deletion was present in 16 of the 22 patients. The 5-year event-free and overall survival rates were 48.6±9.7% and 73.5±8.6%, respectively. The outcome was not satisfactory without sophisticated minimal residual disease-based stratification. Furthermore, the efficacy of TKIs combined with conventional chemotherapy without allogeneic hematopoietic stem cell transplantation in this cohort should be determined.

Cytotoxic Effects of Hydrogen Peroxide on Human Gingival Fibroblasts In Vitro.

In-office bleaching is a popular treatment in modern esthetic dentistry. However, bleaching agents sometimes accidentally adhere to the gingiva and peripheral tissues, even when applied by well-trained dentists. This can lead to transient pain and whitish changes in the gingiva. Although these symptoms disappear within several hours, the effects of bleaching agents on gingiva have not been well described in the literature. The present study aimed to elucidate the cytotoxic effects of a bleaching agent on cultured human gingival fibroblasts (HGFs). We performed a comprehensive analysis of the toxic effects of in-office bleaching agents on gingiva using cultured HGFs and DNA microarray. Survival rates of HGFs decreased with increases in the concentration of hydrogen peroxide, which became significant at concentrations of 1.5 × 10(-3)% or higher at every time point. Concentrations lower than 1.5 × 10(-3)% did not affect survival rates of HGFs. Cytotoxicity of hydrogen peroxide was significantly weakened by the addition of vitamin E. Stimulation by in-office bleaching agents triggered the proinflammatory cytokine tumor necrosis factor (TNF)-α cascade in gingival fibroblasts. As the TNF-α cascade can be inhibited by vitamin E additives, treatment with vitamin E may protect gingival fibroblasts against the toxic effects of an in-office bleaching agent. The present results suggest that local administration of vitamin E to gingiva before in-office bleaching may be useful for preventing gingival irritation due to accidental adhesion of a bleaching agent.

Multidrug resistance protein 4 (MRP4) polymorphisms impact the 6-mercaptopurine dose tolerance during maintenance therapy in Japanese childhood acute lymphoblastic leukemia.

Multidrug resistance protein 4 (MRP4) is involved in the efflux of nucleoside derivatives and has a role in the determination of drug sensitivity. We investigated the relationship between MRP4 genetic polymorphisms and doses of the 6-mercaptopurine (6-MP) and methotrexate. Further, we evaluated the frequency of therapeutic interruption during maintenance therapy in Japanese children with acute lymphoblastic leukemia (ALL). Ninety-four patients received an initial 6-MP dose in the range of 30-50 mg m(-2) in this analysis. Patients with homozygous variant allele in any of MRP4 G2269A, C912A and G559T required high frequency of 6-MP dose reduction compared with non-homozygous individuals. Average 6-MP dose for patients with homozygous variant allele on either MRP4 or inosine triphosphate pyrophosphatase was significantly lower than that for patients with non-homozygous variant allele during maintenance therapy (30.5 versus 40.0 mg m(-2), P=0.024). Therefore, MRP4 genotyping may be useful for personalizing the therapeutic dose of 6-MP during the ALL maintenance therapy in Japanese.

Malignant female adnexal tumor of Wolffian origin (FATWO) positive for CD56: a possible diagnostic role for the biomarker.

Female adnexal tumors of Wolffian origin (FATWOs) are rare tumors that arise in the broad ligament from the remnants of the mesonephric duct. Most FATWOs behave in a benign fashion, and there are only 14 case reports worldwide describing malignant FATWOs. The authors report herein the case of a 69-year-old woman with a malignant FATWO, positive for CD56. The mass was composed mainly of solid neoplastic epithelial cells, closely packed, branching, and anastomosing in slender tubules. There was an eosinophilic secretion within the lumens of some of the cysts and tubules. The number of mitoses was somewhat high in the active areas, numbering five to seven per ten high-power fields. The tumor cells were strongly positive for glutathione S-transferase π, and positive for cal- retinin, vimentin, c-Kit, CD99, and CD56; neuron-specific enolase was also partially expressed. The tumor cells were negative for inhibin α, estrogen receptors, progesterone receptors, B-cell lymphoma 2, and S100. Taken together, these immunohistochemical and pathological findings gave the diagnosis of malignant FATWO. The patient experienced a recurrence one year after her initial surgery. CD56 immunostaining was negative in two benign FATWO cases at the present institution. These findings suggest that CD56-positivity may be a diagnostic biomarker to differentiate malignant FATWOs from benign lesions.

Magnetic resonance imaging appearance of primary spinal extradural Ewing's sarcoma: case report and literature review.

PURPOSE: Primary spinal extradural Ewing's sarcoma (PSEES) or primitive neuroectodermal tumor (PNET) is uncommon. The present study summarizes the magnetic resonance (MR) imaging appearance of PSEES. METHODS: Literature search from 1994 to 2012 with our representative case presentation. RESULTS: Twenty-one patients, 12 males and 9 females, aged 3 weeks to 44 years, were identified. The thoracic spine was most frequently affected, followed by the cervical, cervicothoracic, and thoracolumbar spine. Superior-inferior extension of lesions was three vertebral levels in 7, two in 7, five in 4, four in 1, one in 1 and unknown in 1. PSEESs appeared isointense in 9 cases, hypointense in 2, hyperintense in 1, and no description in 9 on T1-weighted imaging, while hyperintense in 6, hypointense in 3, heterogeneous in 1, and no description in 11 on T2-weighted imaging. Varying enhancement was noted in 13 cases (62 %), with no description of contrast study in the other 8 cases. Dumbbell-shaped configuration of PSEES was found in 5 cases, foraminal widening in 4, and erosions or scalloping of the adjacent vertebral bodies in 4. CONCLUSION: The MR imaging appearance of PSEESs is indistinguishable from other tumors. PSEES should be assumed as the differential diagnosis of spinal extradural tumors in pediatric, adolescent, and young adult patients, and prompt surgical exploration should be performed.

Long-term results of Tokyo Children's Cancer Study Group trials for childhood acute lymphoblastic leukemia, 1984-1999.

We report the long-term results of Tokyo Children's Cancer Study Group's studies L84-11, L89-12, L92-13, and L95-14 for 1846 children with acute lymphoblastic leukemia, which were conducted between 1984 and 1999. The value of event-free survival (EFS)+/-s.e. was 67.2+/-2.2% at 10 years in L84-11, which was not improved in the following two studies, and eventually improved to 75.0+/-1.8% at 10 years in L95-14 study. The lower EFS of the L89-12 reflected a high rate of induction failure because of infection and delayed remission in very high-risk patients. The L92-13 study was characterized by short maintenance therapy; it resulted in poor EFS, particularly in the standard-risk (SR) group and boys. Females did significantly better than males in EFS in the early three studies. The gender difference was not significant in overall survival, partly because >60% of the males survived after the testicular relapse. Randomized studies in the former three protocols revealed that intermediate- or high-dose methotrexate therapy significantly reduced the testicular relapse rate. In the L95-14 study, gender difference disappeared in EFS. Contrary to the results of larger-scale studies, the randomized control study in the L95-14 reconfirmed with updated data that dexamethasone 8 mg/m(2) had no advantage over prednisolone 60 mg/m(2) in the SR and intermediate-risk groups. Prophylactic cranial irradiation was assigned to 100, 80, 44, and 44% of the patients in the studies, respectively. Isolated central nervous system relapse rates decreased to <2% in the last two trials. Secondary brain tumors developed in 12 patients at 8-22 years after cranial irradiation. Improvement of the remission induction rates and the complete omission of irradiation are currently main objectives in our studies.

Cooperation of phosphate monomer and silica modification on zirconia.

Ceramic restorations with resin-based adhesive systems have been the focus of recent attention in clinical dentistry. Yttrium-oxide-partially-stabilized zirconia (YPSZ) ceramics have optimized physical properties and exhibit favorable fracture toughness, though their bonding properties are problematic. Although functional phosphate monomers and silica-coating by tribochemical modification were expected to improve the bonding properties between YPSZ ceramics and resin-based adhesives, these two methods remain controversial. This study evaluated the efficiency of silica-coating by tribochemical modification of YPSZ ceramics. The application of phosphate monomer and a silane coupling agent on silica-coated YPSZ was also investigated. The silica-coating of YPSZ ceramics by tribochemical modification was not efficient, given the higher mechanical toughness of the densely sintered ceramics. Stable shear bond strength was achieved on silica-coated YPSZ ceramics with the cooperative interaction of phosphate monomer and silane coupling.

Therapy-related myelodysplastic syndrome in childhood: a retrospective study of 36 patients in Japan.

We report here a retrospective analysis of 36 children with therapy-related myelodysplastic syndrome (t-MDS) diagnosed between 1990 and 1999 in Japan. Their median age was 7.7 years and the median latency period for the development of t-MDS was 38.5 months. The primary tumors were hematologic in 15 of the cases and nonhematologic in 21. Chromosomal abnormalities were detected in 32/34(94%) patients: abnormalities of chromosomes 5and/or 7 in 41% and notably, 11q23 abnormalities in 31%. The prognosis of children with t-MDS was very poor as compared to children with primary MDS (5 year survival: 16% versus 54%, p<0.0001).

Bonding efficacy and side effects of the high purity glyceryl mono-methacrylate.

The purpose of this study was to examine the efficacy of experimentally developed high purity glyceryl mono-methacrylate (GM) as a dentine primer and to evaluate the possibility of allergic reaction. The efficacy of experimental dentine primers was evaluated by measuring the polymerization contraction gap width and the tensile bond strength. Allergic reaction was evaluated by the guinea-pig maximization test. The skin reaction was evaluated according to the criteria of the International Contact Dermatitis Research Group. Contraction gap formation was completely prevented and the tensile bond strength was not significantly affected by priming with GM on high-purity GM. The allergic response decreased when high-purity GM was employed as the challenger. It was concluded that the clinical use of the high-purity GM is beneficial as the delayed allergic reaction could be avoided with no detrimental effect on the dentine bonding.

MxA expression in patients with viral infection after allogeneic stem cell transplantation.

Many patients suffer febrile diseases soon after allogeneic stem cell transplantation (SCT). Some of the symptoms of viral infections and acute GVHD are often difficult to distinguish. However, an accurate diagnosis is important since the treatments for these conditions are different. It is known that MxA protein is specifically induced in patients with several viral infections. We investigated the cytoplasmic expression of MxA in the peripheral blood mononuclear cells (PBMCs) of patients with fever after allogeneic SCT using a newly generated monoclonal antibody (KM1135) and flow cytometry. The level of MxA expression was significantly higher in patients diagnosed with viral infections (n=6, cytomegalovirus in three, Epstein-Barr virus in one, human herpesvirus-6 in one, adenovirus in one) than control individuals (n=9) (P<0.05, Mann-Whitney test). The level of MxA in patients with aGVHD (n=7) was identical to that in controls. The level of MxA correlated well with the amount of the cytomegalovirus antigen-positive cells in the presence of acute GVHD in two patients. The measurement of MxA is simple and useful in distinguishing viral disease from acute GVHD after allogeneic SCT.

Successful treatment of natural killer (NK) cell leukemia following a long-standing chronic active Epstein-Barr virus (CAEBV) infection with allogeneic bone marrow transplantation.

The optimal treatment for natural killer (NK) cell leukemia after chronic active Epstein-Barr virus (CAEBV) infection has not been determined. A 15-year-old boy presented with NK cell leukemia following CAEBV infection for 5 years. The peripheral blood and BM had an increased number of CD3(-)CD56(+) large granular lymphocytes and a monoclonal integration of the EBV genome was detected. Chemotherapy was not sufficiently effective to control the disease. Allogeneic BMT from an HLA-identical sister was performed using a conditioning regimen consisting of total body irradiation, cyclophosphamide and thiotepa. The patient is disease-free with a perfect performance status 24 months after BMT. This is the first report to show that allogeneic BMT is potentially able to cure NK cell leukemia after CAEBV infection.

Growth of human T cell acute lymphoblastic leukemia lymphoblasts in NOD/SCID mouse fetal thymus organ culture.

The in vitro proliferation of T cell acute lymphoblastic leukemia (T-ALL) cells in its entirety has not been well delineated because of a lack of an appropriate culture system that mimics the growth pattern in a living body. We applied a NOD/SCID mouse fetal thymus organ culture (FTOC) for leukemic cells from fresh (one case) and frozen (seven cases) bone marrow (BM) samples of children with T-ALL. Cell growth was observed in all seven samples in the culture, reaching a proliferational peak at 4 weeks, and it was calculated that the proliferation potential was 212-to 319-fold. The FTOC-derived T-ALL cells showed similarity to the original cells morphologically and immunophenotypically, still possessed clonalities and were able to regenerate overt leukemia in NOD/SCID mice. These FTOC-derived T-ALL cells differed from ordinary cell lines because they always need FTOC support. Thus, we established a new in vitro culture for T-ALL cells. A comparison of the original and FTOC-derived T-ALL cells revealed that the proportion of cells expressing IL-7R increased in all seven cases. Sorting and re-seeding of FTOC-derived IL-7R+ and IL-7R- cells into secondary FTOC resulted in a predominant generation of IL-7R+ cells from both fractions, while IL-7R- cells proliferated more potently than did IL-7R+ cells, suggesting that a pathway for the conversion of IL-7R- to IL-7R+ exists during the proliferation of T-ALL lymphoblasts. Addition of exogenous IL-7 or neutralization with anti-IL-7 antibody did not influence the growth pattern of T-ALL cells in FTOC. The current study provides a unique assay system for the exploration of the hierarchy within human T-lymphoid leukemic cells, and should facilitate the establishment of novel therapeutic modalities.

Successful treatment of relapsed blastic natural killer cell lymphoma with unrelated cord blood transplantation.

The prognosis for blastic natural killer (NK) cell lymphoma is generally dismal. We report a patient who was successfully treated with unrelated cord blood transplantation (UCBT). A 15-year-old boy was diagnosed as having blastic NK cell lymphoma in the cervical lymph nodes. Autologous peripheral blood stem cell transplantation was performed on achieving a complete remission. However, the disease recurred in the bone marrow 6 months later. Chemotherapy induced a second remission and the patient received UCBT with a conditioning regimen consisting of total body irradiation, thiotepa and cyclophosphamide. Chronic GVHD of the lung occurred, but it was well controlled with steroids. At the time of writing, he remains in remission 18 months after UCBT with an excellent performance status. UCBT may be an option for patients with blastic NK cell lymphoma.

Effect of multiple application of dentin bonding agent on marginal integrity of resin composite.

The purpose of the present study was to examine the effect of multiple application of dentin bonding agent to the adhesive surface on the marginal integrity of resin composite. The effect of multiple applications was evaluated by measuring the wall-to-wall polymerization contraction gap and by SEM observation. Multiple application of dentin bonding agent was found to prevent formation of the contraction gap. Although monomer penetration into the enlarged collagen network has been widely discussed as the possible mechanism of the dentin bonding agent and dentin primer, the true detailed mechanism of the dentinal bonding agent and dentin primer should be consistently explained by the prevention of monomer diffusion into the dentin and water contamination of the adhesive interface.

Allogeneic hematopoietic stem cell transplantation for 27 children with juvenile myelomonocytic leukemia diagnosed based on the criteria of the International JMML Working Group.

Prognostic factors of juvenile myelomonocytic leukemia (JMML) have not been clarified because of its very low incidence and inaccuracy in the diagnosis. The purpose of this study was to evaluate children with JMML given an allogeneic hematopoietic stem cell transplantation (SCT) and the role of different variables potentially influencing outcome in a nationwide survey in Japan based on the newly proposed criteria by the International JMML Working Group. The study patients were 27 children who underwent SCT among 55 JMML patients retrospectively collected in the survey. The source of grafts was HLA-identical siblings in 12 cases, HLA-matched unrelated individuals in 10 and others in five. Total body irradiation was used in 18 cases. Event-free and overall survival (OS) at 4 years after SCT were 54.2 +/- 11.2% (s.e.) and 57.9 +/- 11.0% (s.e.), respectively. Six patients died of relapse and three of complications. Patients with abnormal karyotypes showed a significantly lower OS than those with normal karyotypes (P < 0.001). Patients below 1 year of age showed a significantly higher OS than those of 1 year of age or more (P = 0.02). Patients with grade 0-1 acute graft-versus-host disease (GVHD) or chronic GVHD had a more favorable OS than those without them, although they were not statistically significant (P > 0.05). Other variables studied were not associated with OS. A multivariate analysis of these factors yielded the abnormal karyotype as the only significant risk factor for lower OS (risk ratio: 11.0; 95% CI: 2.7-45.1).

Allogeneic bone marrow transplantation in first remission rescues children with Philadelphia chromosome-positive acute lymphoblastic leukemia: Tokyo Children's Cancer Study Group (TCCSG) studies L89-12 and L92-13.

BACKGROUND: The prognosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) is generally poor and reports from large studies are scarce. We evaluated the efficacy of allogeneic bone marrow transplantation (allo-BMT) for children with this type of leukemia. PROCEDURE: The chemotherapy regimens consisted of an induction phase and very intensive consolidation followed by a reinduction phase and late intensification treatment. The selection of treatment modalities such as chemotherapy, allo-BMT, or autologous transplantation was made by each institute. The principal endpoint was the outcome of children with Ph(+) ALL according to the treatment options. RESULTS: Thirty-two patients (4.3%) were diagnosed as Ph(+) ALL out of the 741 cases of ALL consecutively enrolled in two protocols of the Tokyo Children's Cancer Study Group (TCCSG) from 1989 to 1994. Thirty patients (93.8%) were induced into complete remission (CR). Of these 30 patients, eight children electively received allo-BMT in the first CR. Six of these patients are in continuous remission at a median follow-up of 58 (range 48-105) months after the diagnosis. One patient died following recurrence and another patient died of graft vs. host disease. Three patients treated with autologous BMT or peripheral blood stem cell transplantation in the first CR experienced a subsequent relapse. In the remaining 19 patients, 13 patients were treated with very high-risk chemotherapy alone and all relapsed within 28 months. One patient was excluded from the analysis because he was treated with standard-risk chemotherapy until relapse. The other five patients were also excluded from the analysis because Philadelphia chromosome was not detected until they relapsed. None of the relapsed patients survived in spite of treatment including allo-BMT. In multivariate analysis, only allo-BMT remained as an independent factor for good prognosis. CONCLUSIONS: The only way to cure children with Ph(+) ALL was allo-BMT in this study and its outcome seemed promising.