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Aerostatic porous bearings have been applied widely in precision devices to achieve higher accuracy of motion. Conventional aerostatic porous bearings are made of porous graphite, porous ceramics or sintered metal porous material, having a thickness of several millimetres and a surface-restricted layer. However, during mass production of porous bearings, the time required for the production of the porous materials and the surface restriction treatment leads to an increase in the manufacturing time and cost of the porous bearings. Accordingly, to overcome this problem, an aerostatic porous bearing with a layer thickness of several hundred µm and a support member, manufactured using metal 3D printing technology, is proposed. In this study, the optimum conditions for manufacturing the proposed aerostatic porous bearings with a direct metal laser sintering method 3D printer were investigated, and characteristics of the prototype of the proposed bearings were investigated experimentally.

Friction continues to account for the bulk of energy losses in mechanical systems, with an estimated 23% of the world’s total energy consumption used to overcome friction. Concentrated polymer brushes (CPBs) have recently attracted significant scientific and industrial attention, given their ability to achieve superlubricity (i.e., coefficients of friction below 0.01); however, understanding the mechanistic interactions underlying their wear performance has been largely overlooked. Herein, we employ a custom-built optical test apparatus to investigate the inter-dependencies between CPBs and laser-produced surface texture (LST), assessing for the first time the friction, film thickness, and wear behavior in situ and simultaneously. Recent developments in picosecond laser etching allowed us to graft CPBs atop the finest laser-etched matrix of micron-sized dimples reported in literature to date. At low sliding speeds, combined CPB–LST reduces the coefficient of friction to 0.0006, while increasing the CPB durability by up to 34% through a lateral support mechanism offered by the textured micro-features. Furthermore, the imaging results shed light on CPB failure mechanisms. Both these mechanisms of lateral support and failure propagation impact the wear resistance of CPBs and are important in the development of CPBs for future applications (e.g., in low-speed bearings functioning under controlled abrasive wear conditions).

Extraneural recurrence of a medulloblastoma is rare with dismal prognosis. A 9-year-old girl with medulloblastoma was treated with gross total resection followed by a combination of chemotherapy and radiotherapy. Fourteen months after treatment completion, she developed multifocal bone metastases. Despite chemotherapy combined with irradiation, she died 18 months after recurrence due to progressive disease. Fluorescence in situ hybridization on formalin-fixed paraffin-embedded tissue sections revealed MYCNamplification and TP53loss, consistent with the genetic alterations of a rapidly progressive subgroup of recurrent medulloblastomas. In clinical practice, dismal biologic features can be determined using fluorescence in situ hybridization in defective materials.

The frictional properties of diamond-like carbon (DLC) films under boundary lubrication with a synthetic base oil were investigated. The specimens tested were a-C:H, Cr-a-C:H, Ti-a-C:H, W-a-C:H, WC-a-C:H, Mo-a-C:H, MoS2-a-C:H, and Sn-a-C:H films. The tribological properties of DLC/steel contacts were evaluated using a reciprocating-type cylinder-on-disk tribotester. The DLC films exhibited different frictional properties depending on the type of doping elements and compounds used. Notably, the Sn-a-C film gave the lowest friction. The friction tests and static contact angle analyses revealed that the average friction coefficient decreased with a decrease in the static contact angle of the worn DLC film surface, demonstrating that the DLC films with relatively high surface wettabilities exhibited relatively low friction properties. Therefore, surface wettability plays an important role in determining the frictional properties of DLC films under boundary lubrication with synthetic base oil..

Cytokines play key roles in stimulating periodontal regeneration; however, their exact mechanisms of action remain unclear. Mesenchymal stem cells (MSCs) are multipotent cells that have self‐renewal abilities and can differentiate into periodontal tissues such as bone, cementum, and periodontal ligaments following transplantation, like periodontal progenitor cells. Here, we used MSCs to identify the regulatory genes induced by periodontal regenerative cytokines. Human MSCs (hMSCs) were cultured under conditions of periodontal regenerative cytokine stimulation or silencing of undifferentiated hMSC transcription factors. To characterize the changes associated with periodontal regenerative cytokine‐regulated microRNAs (miRNAs), miRNA, and mRNA expression was evaluated using miRNA arrays and quantitative real‐time polymerase chain reaction, respectively. One of the identified miRNAs, miR‐628‐5p, was then overexpressed or suppressed in hMSCs during osteogenesis; the effect of these changes on osteogenesis was investigated. Cytokine‐stimulated MSCs showed characteristic miRNA profiles and mRNA levels of undifferentiated hMSC transcription factors ETV1, SOX11, and GATA6. Next, we silenced these transcription factors in MSCs and examined the miRNA profiles. The levels of miR‐628‐5p were decreased upon all cytokine treatments and were increased upon silencing of ETV1, SOX11, and GATA6. Overexpression of miR‐628‐5p suppressed osteogenesis; however, its inhibition enhanced OPN, ALP, OC, BMP2, and RUNX2mRNA levels, and bone matrix mineralization, but not OSXmRNA or ALP activity. miR‐628‐5p negatively regulates MSC stemness during periodontal regeneration. Periodontal regenerative cytokines act as miR‐628‐5p suppressors to support periodontal regeneration. Thus, selection of effective cytokines for different MSCs, based on miRNA profiling, is important for advancing regenerative therapies.

Supplemental Digital Content is available in the text.Although thiopurine is a crucial drug for treating acute lymphoblastic leukemia, individual variations in intolerance are observed due to gene polymorphisms. A 3-year-old boy with B-cell precursor acute lymphoblastic leukemia who was administered thiopurine developed mucositis, sepsis, and hemophagocytic lymphohistiocytosis due to prolonged hematologic toxicity, chronic disseminated candidiasis, and infective endocarditis that triggered multiple brain infarctions. The patient was found to harbor 3 gene polymorphisms associated with thiopurine intolerance including homozygous NUDT15R139C, heterozygous ITPAC94A, and homozygous MTHFRC677T and heterozygous RFC1G80A. Thus, the combined effect of intolerance via multiple gene polymorphisms should be considered in case of unexpected adverse reactions.

The role of allogeneic hematopoietic stem cell transplantation (HSCT) for infants with acute lymphoblastic leukemia (ALL) and KMT2A gene rearrangement (KMT2A-r) is controversial in terms of both its efficacy and potential for acute and late toxicities. In Japanese Pediatric Leukemia/Lymphoma Study Group trial MLL-10, by introducing intensive chemotherapy, indication of HSCT was restricted to patients with high-risk (HR) features only (KMT2A-r and either age <180 days or presence of central nervous system leukemia). Of the 56 HR patients, 49 achieved complete remission. Forty-three patients received HSCT in first remission including 38 patients receiving protocol-specified HSCT with conditioning consisting of individualized targeted doses of busulfan, etoposide, and cyclophosphamide. Three-year event-free survival (EFS) of 56.8% (95% confidence interval [CI], 42.4% to 68.8%) and overall survival of 80.2% (95% CI, 67.1% to 88.5%) were accomplished. Univariable analysis showed that Interfant-HR criteria and flow cytometric minimal residual disease (MRD; ≥0.01%), both at the end of induction and at the end of consolidation (EOC), were significantly associated with poorer EFS. In the multivariable analysis, positive MRD at EOC was solely associated with poor EFS (P < .001). Rapid pretransplant MRD clearance and tailored HSCT strategy in the MLL-10 trial resulted in a favorable outcome for infants with HR KMT2A-r ALL. However, considering the high rate of potentially life-threatening toxicities and the risk of late effects, its indication should be further restricted or even eliminated in the future by introducing more effective therapeutic modalities with minimal toxicities. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.

The role of allogeneic hematopoietic stem cell transplantation (HSCT) for infants with acute lymphoblastic leukemia (ALL) and KMT2Agene rearrangement (KMT2A-r) is controversial in terms of both its efficacy and potential for acute and late toxicities. In Japanese Pediatric Leukemia/Lymphoma Study Group trial MLL-10, by introducing intensive chemotherapy, indication of HSCT was restricted to patients with high-risk (HR) features only (KMT2A-r and either age <180 days or presence of central nervous system leukemia). Of the 56 HR patients, 49 achieved complete remission. Forty-three patients received HSCT in first remission including 38 patients receiving protocol-specified HSCT with conditioning consisting of individualized targeted doses of busulfan, etoposide, and cyclophosphamide. Three-year event-free survival (EFS) of 56.8% (95% confidence interval [CI], 42.4% to 68.8%) and overall survival of 80.2% (95% CI, 67.1% to 88.5%) were accomplished. Univariable analysis showed that Interfant-HR criteria and flow cytometric minimal residual disease (MRD; ≥0.01%), both at the end of induction and at the end of consolidation (EOC), were significantly associated with poorer EFS. In the multivariable analysis, positive MRD at EOC was solely associated with poor EFS (P< .001). Rapid pretransplant MRD clearance and tailored HSCT strategy in the MLL-10 trial resulted in a favorable outcome for infants with HR KMT2A-r ALL. However, considering the high rate of potentially life-threatening toxicities and the risk of late effects, its indication should be further restricted or even eliminated in the future by introducing more effective therapeutic modalities with minimal toxicities. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative therapy for the hematologic manifestations of Diamond–Blackfan anemia (DBA). However, data regarding the optimal conditioning regimen for DBA patients are limited. We retrospectively compared the outcomes of DBA patients who underwent HSCT using either myeloablative conditioning (MAC) or reduced-intensity conditioning (RIC) regimens. The patients belonged to a cohort treated at our hospitals between 2000 and 2018. HSCT was performed in 27 of 165 patients (16.4%). The median age at the time of HSCT was 3.6 years. Stem cell sources included bone marrow for 25 patients (HLA-matched sibling donors, n= 5; HLA-mismatched related donors, n= 2; HLA-matched/mismatched unrelated donors, n= 18) or cord blood for 2 patients. MAC or RIC regimens were used in 12 and 15 patients, respectively. Engraftment was successful in all 27 patients who underwent HSCT. Three patients who underwent HSCT using MAC regimens developed sinusoidal obstruction syndrome. The 3-year overall survival (OS) and failure-free survival rates (FFS) post-transplantations were 95.2% and 88.4%, respectively, with no significant differences between MAC and RIC regimens. Our data suggest that HSCTs using RIC regimens are effective and obtain engraftment with excellent OS and FFS for young DBA patients.

The friction characteristics of a shock absorber are very complex because the reciprocating motion is not always identical. In this study a device was developed and used to analyze the dynamic friction characteristics under various reciprocating sliding conditions to determine the sliding materials and hydraulic oils that improve the shock absorber performance. This study describes the influence of hydraulic oil additive on the fine reciprocating friction characteristics of steel and copper alloy. Hydraulic oils were prepared by blending a paraffinic mineral oil with zinc dithiophosphate (ZnDTP) and polyhydric alcohol ester as additives. The results show that the dynamic frictional characteristics vary mainly depending on the additive concentration. A specific additive formulation induces a unique amplitude-dependent friction behavior. In addition, the influence of different additives on the lubrication mechanism is investigated based on the instrumental analysis of the friction surface.

Purpose:To examine with intravascular ultrasound (IVUS) the crossing pathways of the TruePath reentry device during primary antegrade recanalization of infrainguinal chronic total occlusions (CTOs). Methods:Between July 2017 and September 2018, a prospective multicenter study enrolled 143 consecutive patients (mean age 75±9 years; 101 men) with 146 CTOs treated in an antegrade approach using the TruePath reentry device with IVUS assessment of the crossing pathway in successful cases. Outcome measures were complete success (reentry device reached the distal true lumen), assisted success (reentry device use followed by a conventional guidewire to reach the distal true lumen), reentry device crossing route by IVUS assessment, and procedure- and device-related complications. Regression analyses were employed to identify any relevant associations between baseline patient variables and the outcome measures; results are presented as the odds ratio (ORs) and 95% confidence interval (CI). Results:Complete success was achieved in 82 (56.2%) lesions; any success (complete plus assisted) was documented in 117 (80.1%) lesions. Four (3%) perioperative device-related complications were observed. The crossing route was intraplaque for most of the total crossing distance in both complete success cases (95.3%±13.2%) and any success cases (94.8%±14.4%), with relatively short subintimal (3.6%±10.2% and 4.2%±11.2%, respectively) or intramedial (1.2%±5.8% and 1.0%±5.4%, respectively) crossing. CTO length was a significant risk factor for not achieving complete success (OR 1.74, 95% CI 1.13 to 2.68, p=0.012), and a history of failed revascularization was associated with not achieving any success (OR 6.40, 95% CI 1.28 to 28.9, p=0.038). Conclusion:The intraplaque route was the primary pathway taken by the TruePath reentry device as it crossed infrainguinal CTOs. Crossing rates were acceptable, with few device-related complications. However, a longer CTO length and a failed revascularization history negatively affected the success rate.

Purpose: Surgical thromboendarterectomy has been the gold standard treatment for common femoral artery (CFA) disease. However, endovascular therapy (EVT) is conducted in certain patients with CFA lesions because of multiple comorbidities. The interwoven nitinol stent (IWS) has been developed to prevent stent fracture. Thus, this study aimed to evaluate the feasibility of EVT using IWS for CFA lesions in clinical practice.Materials and methods: This retrospective multicenter registry analyzed patients who had symptomatic lower-extremity artery disease due to CFA lesions and underwent EVT using IWS between 2019 and 2021. The primary endpoint was restenosis 2 years after EVT.Results: This study enrolled a total of 177 patients with 196 CFA lesions. The 2-year estimate of freedom from restenosis was 88.0%. The 2-year freedom rates from the target-lesion revascularization, major amputation, and all-cause death were 92.9%, 99.0%, and 75.2%, respectively. The clinical features significantly associated with restenosis risk were the reference vessel diameter (RVD, per 1.0 mm, hazard ratio [HR], 0.24 [0.08–0.70]; p=0.009), external iliac artery (EIA) involvement (HR=4.03 [1.56–10.4]; p=0.004), superficial femoral artery (SFA) involvement (HR=3.05 [1.00–9.25]; p=0.049), body mass index (BMI; per 1.0, HR=0.85 [0.73–0.99]; p=0.032), occlusion of deep femoral arteries (DFAs) at baseline (HR=7.89 [2.04–30.5]; p=0.003), and chronic limb-threatening ischemia (CLTI, HR=2.63 [1.02–6.78]; p=0.045). Their significant association was also confirmed by the random survival forest analysis. During a median follow-up of 12.0 months, guiding sheaths were inserted via CFAs implanted IWSs in 73 cases (37.2%), and no patients had cannulation-related complications, such as failed hemostasis, fracture of IWS, and stent occlusion.Conclusions: Endovascular therapy using IWS in CFA lesions showed acceptable 2-year patency rates at 88.0% and might preserve the arterial access via the ipsilateral CFAs. Small RVD, involving EIA and SFA lesions, emaciation, occluded DFA, and CLTI are associated with poor 2-year patency rates following EVT, thus, IWS implantation in CFA lesions may be an option for patients unsuitable for surgical revascularization.Clinical Impact This retrospective multicenter registry enrolled 177 patients with 199 CFA lesions treated with EVT using interwoven nitinol stents, because surgical thromboendarterectomy was difficult due to their multiple comorbidities. The 2-year estimate of freedom from restenosis was acceptable at 88.0%. The 2-year freedom rate from major amputation was also high at 99.0%. Moreover, during a median follow-up of 12.0 months, guiding sheaths were inserted via CFAs implanted IWSs in 73 cases, and no patients had cannulation-related complications such as failed hemostasis, fracture of IWS, and stent occlusion.

•This study provides an overall picture of driver mutations in ML-DS, including novel and frequent IRX1and ZBTB7Amutations, and RUNX1-PTD.•CDKN2Aand TP53deletions and/or mutations are associated with a poor prognosis in ML-DS.

Recently, brain‐derived neurotrophic factor (BDNF)/high molecular weight hyaluronic acid (HMW‐HA) complex with flap surgery has been shown to promote periodontal tissue regeneration. The objective of this study was to evaluate the effects of local subgingival application of BDNF/HMW‐HA complex adjunctive to scaling and root planning (SRP) on ligature‐induced periodontitis in dogs. The dogs were divided into four treatment groups: no treatment (control), SRP alone, SRP followed by local application of HMW‐HA (SRP+HMW‐HA), and SRP followed by local application of BDNF (500 μg/ml)/ HMW‐HA complex (SRP+BDNF/HMW‐HA). HMW‐HA or BDNF/HMW‐HA complex was topically applied to periodontal pockets using a syringe without surgery. Two weeks after treatment, clinical parameters (gingival index, clinical attachment level, periodontal pocket depth and bleeding on probing) were recorded and specimens were collected from anesthetized animals for histological analysis. The SRP+BDNF/HMW‐HA group showed significant improvement in all clinical parameters compared to other treatment groups. Histologic analysis showed greater suppression of apical migration of epithelial tissue and milder inflammatory cell infiltration in the SRP+BDNF/HMW‐HA group than in the other treatment groups. Furthermore, new cementum and alveolar bone were regenerated, and collagen fibers were inserted into them in the SRP+BDNF/HMW‐HA group. BDNF/HMW‐HA complex as an adjunct to nonsurgical periodontal treatment has the potential to reduce excess inflammation. Further investigation will be needed to clarify periodontal tissue regenerative effects of BDNF/HMW‐HA complex in a nonsurgical setting.

A 3-year-old boy was clinically diagnosed with Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis. We identified EBV-infected CD8-positive T-lymphocytes by cytologic double staining of the peripheral blood for EBV-encoded small RNA and cell surface markers. The patient was subsequently administered immunosuppressive therapy with a reduced dose of etoposide because of previous organ damage. EBV clearance was confirmed by serial quantification of cell-fractionated EBV-DNA, whereas EBV-DNA persisted in the plasma for 18 weeks. Immunochemotherapy with low-dose etoposide combined with serial viral load monitoring is a potential therapeutic option for severe EBV-hemophagocytic lymphohistiocytosis cases with organ damage.

X-linked recessive ectodermal dysplasia with immunodeficiency is a rare primary immunodeficiency caused by hypomorphic mutations of the IKBKGgene encoding the nuclear factor κB essential modulator (NEMO) protein. This condition displays enormous allelic, immunological, and clinical heterogeneity, and therapeutic decisions are difficult because NEMO operates in both hematopoietic and nonhematopoietic cells. Hematopoietic stem cell transplantation (HSCT) is potentially life-saving, but the small number of case reports available suggests it has been reserved for only the most severe cases. Here, we report the health status before HSCT, transplantation outcome, and clinical follow-up for a series of 29 patients from unrelated kindreds from 11 countries. Between them, these patients carry 23 different hypomorphic IKBKGmutations. HSCT was performed from HLA-identical related donors (n = 7), HLA-matched unrelated donors (n = 12), HLA-mismatched unrelated donors (n = 8), and HLA-haploidentical related donors (n = 2). Engraftment was documented in 24 patients, and graft-versus-host disease in 13 patients. Up to 7 patients died 0.2 to 12 months after HSCT. The global survival rate after HSCT among NEMO-deficient children was 74% at a median follow-up after HSCT of 57 months (range, 4-108 months). Preexisting mycobacterial infection and colitis were associated with poor HSCT outcome. The underlying mutation does not appear to have any influence, as patients with the same mutation had different outcomes. Transplantation did not appear to cure colitis, possibly as a result of cell-intrinsic disorders of the epithelial barrier. Overall, HSCT can cure most clinical features of patients with a variety of IKBKGmutations.

X-linked recessive ectodermal dysplasia with immunodeficiency is a rare primary immunodeficiency caused by hypomorphic mutations of the IKBKG gene encoding the nuclear factor κB essential modulator (NEMO) protein. This condition displays enormous allelic, immunological, and clinical heterogeneity, and therapeutic decisions are difficult because NEMO operates in both hematopoietic and nonhematopoietic cells. Hematopoietic stem cell transplantation (HSCT) is potentially life-saving, but the small number of case reports available suggests it has been reserved for only the most severe cases. Here, we report the health status before HSCT, transplantation outcome, and clinical follow-up for a series of 29 patients from unrelated kindreds from 11 countries. Between them, these patients carry 23 different hypomorphic IKBKG mutations. HSCT was performed from HLA-identical related donors (n = 7), HLA-matched unrelated donors (n = 12), HLA-mismatched unrelated donors (n = 8), and HLA-haploidentical related donors (n = 2). Engraftment was documented in 24 patients, and graft-versus-host disease in 13 patients. Up to 7 patients died 0.2 to 12 months after HSCT. The global survival rate after HSCT among NEMO-deficient children was 74% at a median follow-up after HSCT of 57 months (range, 4-108 months). Preexisting mycobacterial infection and colitis were associated with poor HSCT outcome. The underlying mutation does not appear to have any influence, as patients with the same mutation had different outcomes. Transplantation did not appear to cure colitis, possibly as a result of cell-intrinsic disorders of the epithelial barrier. Overall, HSCT can cure most clinical features of patients with a variety of IKBKG mutations.

In this research, we focus on the improvement of frictional performance of piston ring achieved by Laser Surface Texturing. Five kinds of samples (non-texture, dimple 100μm, dimple120μm, groove 45 degrees to sliding direction and groove 90 degrees to sliding direction) were tested under reciprocating sliding condition. The results showed that the sample of groove 90 degrees to sliding condition has the maximum decrease on either average friction coefficient (26%) or friction coefficient at end points of stock (33%). And we think that under boundary lubrication regime, the uniformity of distribution of the texture and flow of oil in contact surface are the key factors which affect the friction coefficient.

Purpose:To investigate the angiographic dissection patterns after balloon angioplasty for superficial femoral artery (SFA) lesions, the clinical outcome associated with each dissection pattern, and the predictive factors for severe dissection. Methods:A retrospective, multicenter analysis examined 621 patients (mean age 72.8±9.5 years; 414 men) with 748 symptomatic de novo SFA lesions treated with endovascular therapy. Vessel dissection after the initial balloon angioplasty procedure was graded into 7 types according to a modified version of the coronary artery classification types A to F. Severe vessel dissection patterns were defined as type C or higher. Nitinol stent implantation was performed in 555 (74.2%) lesions for residual stenosis >30% or flow-limiting dissection; 193 lesions (25.8%) were treated with balloon angioplasty only. To determine the clinical outcomes associated with each dissection pattern and identify predictive factors for severe dissection, 2-year follow-up data for the 193 lesions treated with balloon angioplasty only were analyzed for primary patency and clinically driven target lesion revascularization (TLR). Results:No dissection was found in 16% (120/748) of lesions, and types A and B dissections were seen in 19% (142/748) and 23% (172/748), respectively. Dissection grades above type C were observed in 42% of cases, most frequently type D (180/748, 24%) and less often type C (37/748, 5%), type E (67/748, 9%), and type F (30/748, 4%). The bailout stent implantation rate increased according to dissection severity. At up to 2 years, the severe dissection group (types C–F) showed a significantly lower patency rate (p<0.001) and higher clinically driven TLR (p<0.001) compared to the nonsevere group (no dissection and types A and B dissections). Severe dissection was a significant risk factor for restenosis, which rose progressively from types C to F. Multivariate analysis identified a small reference vessel diameter <5 mm (p=0.001), lesion length >15 cm (p=0.001), and chronic total occlusion (p<0.001) as independent predictors of severe dissection. In subgroup analysis, vessels with a small reference diameter and TASC II C and D lesions had a higher prevalence of severe dissection. Conclusion:Severe dissection was found in 42% of cases after PTA. A small vessel diameter and/or TASC II C/D lesions were related to a high incidence of dissection. Severe dissection during procedures employing balloon angioplasty only could affect long-term patency.

Human gingival epithelial cells (HGECs) function as a mechanical barrier against invasion by pathogenic organisms through epithelial cell–cell junction complexes, which are complex components of integrin. Integrins play an important role in the protective functions of HGECs. Human periodontal ligament (HPL) cells regulate periodontal homeostasis. However, periodontitis results in the loss of HPL cells. Therefore, as replenishment, HPL cells or mesenchymal stem cells (MSCs) can be transplanted. Herein, HPL cells and MSCs were used to elucidate the regulatory mechanisms of HGECs, assuming periodontal tissue homeostasis.

To understand the effects of tribo-film formation derived from ZnDTP (zinc dialkyl ditio phosphate) on friction behavior, friction tests were carried out with varying sliding time. The sliding surfaces were analyzed using Fourier transform infrared spectroscopy (FT-IR) and X-ray Photoelectron Spectroscopy (XPS). On the basis of the surface analytical results of the tribo-film, the absorption bands in the region of 1300-1000 cm-1 assigned as polyphosphate appeared in all IR spectra after the sliding. The friction behavior of ZnDTP was related to the intensity change of the IR spectra peak at 1200 cm-1.

The friction behaviour of grinded and polished surfaces was evaluated by using a reciprocal sliding tester under lubrication with PAO, PAO + ZnDTP and PAO + ZnDTP + MoDTC. Friction coefficients on the smooth surfaces showed higher values compared to those on the rough surfaces. For lubrication incorporating PAO and PAO + ZnDTP + MoDTC, friction coefficients on both the smoothest and the roughest surfaces decreased with sliding time. On the other hand, friction coefficients between these extremes decreased with sliding time. In this paper, the effects of surface roughness on friction behaviour are discussed.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

ADC12 is a eutectic Al–Si die-cast alloy (Al–12Si) widely used instead of cast iron for industrial parts in order to reduce their weight. Here, to improve the wear resistance, SiC and diamond particles were dispersed into the surface of the ADC12 alloy. The tribological properties of the hard-particle-dispersed ADC12 samples under lubrication were evaluated using a vane-on-plate tribometer and compared to those of hypereutectic Al–Si alloy (Al–15Si). Three different kinds of vane materials, carbon steel, die steel and high-speed steel, were used as counter materials. The diamond-dispersed ADC12 alloy showed the most significant wear reduction effect when sliding against die steel and high-speed steel, and the lowest coefficient of friction was obtained when high-speed steel was used as the counter material. The durability tests using a conventional pump and the modified materials confirmed the significant improvement in the wear resistance of hard-particle-dispersed ADC12.

Recently, compact machine tools have witnessed increased demand in the manufacture of small parts with high accuracy. However, miniaturization of these machines poses problems such as decrease in the accuracy and the range of motion. We focused on miniaturizing a parallel link manipulator, which is known to have high rigidity and accuracy. A non-cylindrical link was adopted in the designed manipulator for avoiding collisions among links with an impact drive actuator attached to their side. We confirmed through repeatability measurements that the developed manipulator had sufficient accuracy for handling small electronic parts.

Ionic liquids are expected to be used as new high-performance lubricants because of their low volatility, high thermal stability, and high oxidation stability. It is well known that some ionic liquids exhibit excellent lubricity for metals. On the other hand, there is concern about the corrosiveness of ionic liquids caused by tribo-chemical reactions. In this study, the lubricating properties of seven kinds of commercially available ionic liquids were evaluated under steel-on-steel sliding contacts using an SRV oscillating sliding tester. The worn surfaces were analyzed by optical microscopy, confocal laser scanning microscopy, scanning electron microscopy with energy dispersive X-ray spectrometry, and X-ray photoelectron spectroscopy. The halogen-containing ionic liquids exhibited excellent lubricity for steel compared with the halogen-free ionic liquids. The X-ray photoelectron spectroscopy analytical results showed the formation of iron fluoride on sliding surfaces lubricated with the fluorine-containing ionic liquids. Formation of this iron-fluoride boundary layer reduced friction; however, corrosion occurred on the worn surfaces after the sliding. On the other hand, less corrosive damage was observed on the worn surfaces that slid under the dry-nitrogen atmospheric condition. These results suggested that the hydrofluoric acid, which was produced by the reaction between iron fluoride and contaminated water from the atmosphere, caused the corrosion on the worn surface. The halogen-free ionic liquids showed inferior lubricity compared with the halogen-containing ionic liquids, though they did not cause any remarkable corrosion. The corrosion-inhibition effect of the phosphorus element was shown in the halogen-containing ionic liquids composed of a phosphate anion or phosphonium cation. The friction-reduction effect was, however, inferior to that of the phosphorus-free ionic liquids. The tribo-chemical reaction of the phosphorus contained in the ionic liquids yielded a phosphate boundary layer that prevented the formation of iron halide on the sliding surface and enhanced the wear resistance.

Somatic mosaicism has been described in several primary immunodeficiency diseases and causes modified phenotypes in affected patients. X-linked anhidrotic ectodermal dysplasia with immunodeficiency (XL-EDA-ID) is caused by hypomorphic mutations in the NF-κB essential modulator (NEMO) gene and manifests clinically in various ways. We have previously reported a case of XL-EDA-ID with somatic mosaicism caused by a duplication mutation of the NEMO gene, but the frequency of somatic mosaicism of NEMO and its clinical impact on XL-EDA-ID is not fully understood. In this study, somatic mosaicism of NEMO was evaluated in XL-EDA-ID patients in Japan. Cells expressing wild-type NEMO, most of which were derived from the T-cell lineage, were detected in 9 of 10 XL-EDA-ID patients. These data indicate that the frequency of somatic mosaicism of NEMO is high in XL-ED-ID patients and that the presence of somatic mosaicism of NEMO could have an impact on the diagnosis and treatment of XL-ED-ID patients.

Somatic mosaicism has been described in several primary immunodeficiency diseases and causes modified phenotypes in affected patients. X-linked anhidrotic ectodermal dysplasia with immunodeficiency (XL-EDA-ID) is caused by hypomorphic mutations in the NF-κB essential modulator (NEMO)gene and manifests clinically in various ways. We have previously reported a case of XL-EDA-ID with somatic mosaicism caused by a duplication mutation of the NEMOgene, but the frequency of somatic mosaicism of NEMOand its clinical impact on XL-EDA-ID is not fully understood. In this study, somatic mosaicism of NEMOwas evaluated in XL-EDA-ID patients in Japan. Cells expressing wild-type NEMO, most of which were derived from the T-cell lineage, were detected in 9 of 10 XL-EDA-ID patients. These data indicate that the frequency of somatic mosaicism of NEMOis high in XL-ED-ID patients and that the presence of somatic mosaicism of NEMOcould have an impact on the diagnosis and treatment of XL-ED-ID patients.

ZrO2(Y2O3)-Al2O3-SrSO4 nanocomposites incorporated with and without Ag addition have been fabricated by spark plasma sintering (SPS) to evaluate their friction and wear properties in sliding against alumina ball from room temperature to 600 oC. X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman spectroscopy were used to investigate microstructure and self-lubrication mechanisms of nanocomposites after wear tests at different temperatures. The ZrO2(Y2O3)-Al2O3-SrSO4 nanocomposite exhibits low and stable friction coefficients of 0.2 to 0.3 and wear rates in the order of 10-6 mm3/Nm at high temperatures. With the addition of Ag into the composite, the intermediate temperature lubricating property is greatly improved. Plastic deformation of SrSO4 and sliver during sliding plays an important role in formation of lubricating films on worn surfaces of nanocomposites. These lubricating films reduce the friction and wear of the ZrO2(Y2O3)-Al2O3 matrix composites.

In this study, Zr, Ti and TiC-based cermet specimens were prepared, and their friction and wear properties in various gas atmospheres were examined. The Zr specimens exhibited the lowest friction coefficients and the smallest volume change in the H2 gas atmosphere. This reason would have been due to the formation of the -type Zr hydride, which has a layered crystal structure. The Ti specimens exhibited similar friction and wear properties, although the TiC-based cermet specimens containing small amount of Mo, Ni and W exhibited the lowest friction coefficients in air, not in the H2 gas atmosphere. The low friction coefficients of the cermet specimens in air is likely to have been due to the formation of the low friction Mo oxides and W oxides.

Abstract: The Earth is facing many serious environmental problems. The global warming problem has reached a point at which action cannot be delayed. It is necessary not only to expect novel technological development but also to create realistic solutions by extending conventional technologies. Tribology has supported various technological developments over the years and has also responded promptly to societal demands for decreasing substances from engineering products that would be hazardous to the environment. As societies aim to become sustainable, tribology needs to be involved and contribute to the solution more than ever before. Environmentally friendly tribology, eco-tribology, through progress in surface modification, is seen to be an effective engineering technology that can contribute very much to sustainable societies. Multi-scale surface texturing, which is a new concept of surface modification for tribo-materials, and diamond-like carbon (DLC) coating technology were introduced as the expected future development.

Abstract: Recent engineering products must meet the demand for downsizing and sophistication. Environmentally benign manufacturing has also become a key technology for sustainable development. Striking a balance between product quality and environmental impact in manufacturing processes has become an important issue in the design of eco-friendly products. However, despite this increasing demand from the industry, there is dearth of research on the environmental impact of processing as compared to studies on conventional manufacturing factors such as cost and time. We have tried to clarify the relationship between quality and environmental impact directly from experimental data. The pitting process that we chose as our experimental process is one of the most general and important processes in the industry. In this paper, we discuss a basic concept for selecting optimal processing methods and conditions for the pitting process from the aspect of employing an environmentally benign process. By applying our study to the industry, engineers can easily conduct processes that are not only high in quality but also low in environmental impact.

Background KMT2A-rearranged acute lymphoblastic leukemia (KMT2A-r ALL) is a rare and dismal disease in infants. Despite restriction of the indication of allogeneic hematopoietic stem cell transplantation to the high-risk group (patients aged <180 days with KMT2A-r ALL or central nervous system involvement), adoption of an Interfant-06-based induction therapy with stricter age-related dosing followed by COG AALL0631-based post-remission chemotherapy with additional administration of high-dose cytarabine in the early intensification phase led to rapid clearance of minimal residual disease (MRD) in the Japanese Pediatric Leukemia/Lymphoma Study Group (JPLSG) MLL-10 trial. The MLL-10 trial demonstrated an improved outcome of 66.2% in 3-year event-free survival (EFS) among infants with KMT2A-r ALL (Tomizawa D. Blood 2021). As the Interfant-06 study showed an association between the expression levels of myeloid markers (MM) and poor MRD clearance at end of induction (EOI) and a high relapse rate (Stutterheim J, J Clin Oncol.2021), we analyzed the significance of MM expression in the MLL-10 cohort and its association with prognosis.

No relevant conflicts of interest to declare.

The high-temperature friction and wear characteristics of different ceramics and ceramic matrix composites (CMCs) incorporated with various solid lubricants have been investigated from room temper- ature to 1000oC. The solid lubricants considered in this paper include representative precious metals, hexagonal boron nitride, graphite, fluorides, soft oxides, chromates, sulfates, and combinations of various solid lubricants. General design considerations relevant to solid lubrication were proposed on the basis of friction and wear data of self-lubricating CMCs. The self-lubricating composites incorporated with SrSO4 or/and CaSiO3 exhibits low and stable friction coefficients of 0.2 to 0.3 and small wear rates in the order of 10-6 mm3/Nm from room temperature to 800oC. The optimized composites appear to be promising can- didates for long-duration, extreme environment applications with low friction and small wear rate.

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The friction and wear properties of phosphor bronze discs sliding against SAE52100 steel balls were evaluated using an Optimol SRV reciprocating friction and wear tester under the lubrication of pure poly-alpha-olefin (PAO) and PAO containing commercial phosphite ester, zinc dialkyldithiophosphate (ZDTP) and oleic acid additives. The morphologies of the worn surfaces of the phosphor bronze discs were observed using a scanning electron microscope (SEM). In addition, the elemental compositions and chemical states of several typical elements on the worn surfaces of the phosphor bronze discs were examined by means of X-ray photoelectron spectroscopy (XPS). The findings indicated that the phosphor bronze discs exhibited higher wear resistance under the lubrication of PAO containing phosphite ester than pure PAO, PAO containing ZDTP, and PAO containing oleic acid. Also, the phosphor bronze discs exhibited stable friction coefficients as low as 0.09-0.11 when lubricated with PAO containing phosphite ester. According to the XPS analyses, it was considered that the formation of CuO and phosphate led to lower friction coefficient and high wear resistance of phosphor bronze specimens lubricated with PAO containing phosphite ester. In the case of the phosphor bronze specimens lubricated with PAO containing ZDTP and oleic acid, the formation of organic compounds seemed to lead to lower friction coefficient, but did not seem to affect the wear resistance.

In this study, Fe-2.0Si-4.6C (mass%) gray cast iron disk specimens with three different matrix phases were coated with MoS2 using pressure spraying, and the friction and wear properties of the specimens were investigated against AISI52100 steel and polytetrafluoroethylene balls under the lubrication of oil using an Optimol SRV friction tester. When AISI52100 steel balls were used as the paired material, all of the MoS2-coated gray cast iron specimens showed lower friction coefficients and higher wear resistance than the non-coated disk specimens. On the other hand, MoS2-coated gray cast iron specimens exhibited higher friction coefficients than non-coated disk specimens for the most part, when polytetrafluoroethylene balls were used as the paired material.

The friction and wear characteristics of a cathodic arc ion-plated CrSiN coating in sliding against different counter materials have been investigated under both unlubricated and boundary-lubricated conditions. Under boundary-lubricated conditions, the CrSiN coating exhibits a friction coefficient of 0.12 to 0.20 against a SAE 52100 steel ball and of 0.04 to 0.07 against a CrN-coated steel pin, depending on wear parameters used. The effects of load, temperature and counter materials on friction and wear of the CrSiN coating were discussed. The worn surfaces and wear debris generated under different wear conditions were examined by means of scanning electron microscopy and Raman spectroscopy to identify the tribochemical reaction and phase structures generated during the wear process. Under unlubricated conditions, iron-based oxides formed in sliding against a steel ball, while some chromium oxides were identified on worn surfaces of the CrSiN coating in sliding against an alumina ball in air.

Spark plasma sintering is employed to synthesize a variety of self-lubricating ZrO2(Y2O3)- Al2O3 matrix nanocomposites by tailoring the chemical compositions and by adjusting the sintering parameters. Different additives are incorporated into the nanocrystalline ceramics of ZrO2(Y2O3)- 20wt.% Al2O3 to evaluate their potentials as effective high temperature solid lubricants from room temperature to 800oC by using a high temperature friction and wear tester in sliding against alumina ball in air. The density, microstructure, hardness and tribological properties of the sintered nanocomposites have been investigated, as contrasted with the unmodified ceramics, to obtain a better understanding of lubrication mechanisms over a wide temperature range. The ZrO2(Y2O3)-Al2O3-SrSO4 composite exhibits steady-state friction coefficients of less than 0.2 and wear rates in the order of 10-6 mm3/Nm over a broad temperature range from room temperature to 800oC.

In the present study, Al2O3, (ZrO2-3mol% Y2O3)-39.6mass% Al2O3, Si3N4 and MgO substrates coated with SrSO4 particles were prepared, and their high-temperature tribological properties were investigated. It was clarified that SrSO4 worked as solid lubricant efficiently against Al2O3 and (ZrO2-3mol% Y2O3)-39.6mass% Al2O3 substrates in the temperature range of room temperature to 1073K in air. In addition, thin SrSO4 films were observed on the wear scars formed on the Al2O3 and (ZrO2-3mol% Y2O3)-39.6mass% Al2O3 substrates.

Abstract: Previously we reported that purified Cell Wall Peroxidase-Cationic (CWPO-C) from poplar callus (Populus alba L.) oxidizes sinapyl alcohol and polymeric substrate unlike other plant peroxidases and proposed that this isoenzyme is a conceivable lignification specific peroxidase. In this study, we cloned full-length cDNA of CWPO-C and investigated the transcription of CWPO-C gene in various organs and the localization of CWPO-C protein in the differentiating xylem of poplar stem.Real-time PCR analyses indicated that CWPO-C gene is constitutively expressed in the developing xylem, leaf, and shoot but not affected by many stress treatments. Immunohistochemical analysis showed that CWPO-C locates in the middle lamellae, cell corners, and secondary cell walls of the fiber cells during the lignification. The intensity of the CWPO-C labeling increased gradually from the cell wall thickening stage to mature stage of fiber cells, which is very consistent with the increase of lignin content in the developing xylem. These results strongly support that CWPO-C is responsible for the lignification of the secondary xylem. Interestingly, immuno-labeling of CWPO-C was also observed inside of the ray parenchyma cells instead no signals were detected within the developing fiber cells. This suggests that CWPO-C is biosynthesized in the parenchyma cells and provided to the middle lamellae, the cell corners, and the cell walls to achieve lignin polymerization.

The electrical conduction of self-assembled monolayers (SAMs) made from conjugated molecules was measured using conductive probe atomic force microscopy (CP-AFM), with a focus on the molecular structural effect on conduction. First, the electrical conduction of SAMs made from phenylene oligomer SAMs was measured. The resistances through the monolayers increased exponentially with an increase in molecular length and the decay constants of transconductance ? were about 0.45 to 0.61 Å?1measured at lower bias region. We further investigated the influence of applied load on the resistances. The resistances through terphenyl SAMs increased with an increase in the applied load up to 14 nN. Second, using an insertion technique into insulating alkanethiol SAMs, the electrical conduction of single conjugated terphenyl methanethiol and oligo(para-phenylenevinylene) (OPV) molecules embedded into insulating alkanethiol SAMs were measured. Electrical currents through these single molecules of OPVs were estimated to be larger than those through single terphenyl molecules, suggesting that the OPV structure can increase the electrical conduction of single molecules. Third, apparent negative differential resistance (NDR) was observed at higher bias measurements of SAMs. The appearance of NDR might be related to roughness of SAM surface, because apparent NDR was often observed on rough surfaces. In any case, the tip-molecule contact condition strongly affected carrier transport through metal tipSAMmetal junction.

The transcription factor Bach2, a member of the CNC family of proteins, binds to the Maf recognition element (MARE) by forming homodimers or dimerizing with small Maf transcription factors. Bach2-expressing cells show reduced proliferation and undergo spontaneous cell death. The inhibition of BCR/ABL tyrosine kinase activity by STI571 in chronic myeloid leukemia (CML) cell lines and CD34+cells from patients with CML in lymphoid crisis results in induction of BACH2 expression. We show here that BACH2 modifies the in vitro cytotoxicity of anticancer drugs. The cytotoxic effects of commonly used anticancer agents were studied by overexpression of BACH2 in RAJI lymphoid cells, a cell line that does not express endogenous BACH2. Cell growth inhibition was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Clones overexpressing BACH2 were more sensitive to etoposide, doxorubicin, and cytarabine than control RAJI cells, whereas there were no significant differences in the sensitivity of either cells to methotrexate or vincristine. Interestingly, we found that the former drugs were oxidative stressors that induced the nuclear accumulation of BACH2. In contrast, methotrexate or vincristine did not induce production of intracellular reactive oxygen species (ROS) and nuclear accumulation of BACH2. These results, coupled with our previous data showing that BACH2 promotes oxidative stress-induced cell death, suggest that combination chemotherapy involving STI571 and anticancer drugs that produce ROS may be of benefit in the treatment of Philadelphia chromosome 1 (Ph1)–positive leukemia.

The transcription factor Bach2, a member of the CNC family of proteins, binds to the Maf recognition element (MARE) by forming homodimers or dimerizing with small Maf transcription factors. Bach2-expressing cells show reduced proliferation and undergo spontaneous cell death. The inhibition of BCR/ABL tyrosine kinase activity by STI571 in chronic myeloid leukemia (CML) cell lines and CD34+ cells from patients with CML in lymphoid crisis results in induction of BACH2 expression. We show here that BACH2 modifies the in vitro cytotoxicity of anticancer drugs. The cytotoxic effects of commonly used anticancer agents were studied by overexpression of BACH2 in RAJI lymphoid cells, a cell line that does not express endogenous BACH2. Cell growth inhibition was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Clones overexpressing BACH2 were more sensitive to etoposide, doxorubicin, and cytarabine than control RAJI cells, whereas there were no significant differences in the sensitivity of either cells to methotrexate or vincristine. Interestingly, we found that the former drugs were oxidative stressors that induced the nuclear accumulation of BACH2. In contrast, methotrexate or vincristine did not induce production of intracellular reactive oxygen species (ROS) and nuclear accumulation of BACH2. These results, coupled with our previous data showing that BACH2 promotes oxidative stress-induced cell death, suggest that combination chemotherapy involving STI571 and anticancer drugs that produce ROS may be of benefit in the treatment of Philadelphia chromosome 1 (Ph1)–positive leukemia.

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Two peroxidases, CWPO-A and CWPO-C, were isolated from the cell walls of poplar (Populus albaL.) callus culture. The cationic CWPO-C showed a strong preference for sinapyl alcohol over coniferyl alcohol as substrate. Thus, the monolignol utilization of CWPO-C is unique compared with other peroxidases, including anionic CWPO-A and horseradish peroxidase (HRP). CWPO-C polymerized oligomeric sinapyl alcohol (S-oligo) and sinapyl alcohol, producing a polymer of greater molecular weight. In contrast, HRP, which is specific to coniferyl alcohol, produced sinapyl alcohol dimers, rather than catalyzing polymerization. Adding coniferyl alcohol as a radical mediator in the HRP-mediated reaction did not result in S-oligo polymerization. This report shows that CWPO-C is an isoenzyme specific to sinapyl alcohol that polymerizes oligomeric lignols. Its catalytic activity toward oligomeric lignols may be related to the lignification of angiosperm woody plant cell walls.