Development of novel projection-type imaging mass spectrometer.

We developed a novel imaging mass spectrometer based on our accumulating technology for projection-type imaging mass spectrometry, the simulation of an accurate ion trajectory, and the theory for ion optics. The newly developed apparatus yields high spatial resolution with a substantially shorter image-acquisition time compared with conventional scanning-type imaging mass spectrometers. In order to maintain a high mass resolution, a multi-turn time-of-flight mass spectrometer is combined with post-extraction differential acceleration methods. Consequently, a mass resolution of m/Δm ∼ 10 000 and a spatial resolution of 1 µm were achieved simultaneously in this study. Application of our newly established apparatus to biological samples accomplished successful imaging mass spectrometry by exhibiting an organ-specific distribution of endogenous ions as well as a localized distribution of exogenously applied ions with an ultra-high spatial resolution image in the size of 18.5 megapixels.

Effect of tumor burden and growth rate on treatment outcomes of nivolumab in head and neck cancer.

BACKGROUND: Nivolumab improves overall survival (OS) in patients with platinum-refractory recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). In one study, however, Kaplan-Meier OS and progression-free survival (PFS) curves for the nivolumab and cytotoxic agent arms crossed at 3-6 months, suggesting that patients with initial resistance to immunotherapy might have better outcomes with cytotoxic treatment. Here, we explored the conditions and candidates which are predictive of nivolumab outcomes in R/M HNSCC. METHODS: We retrospectively reviewed the clinical records of 27 consecutive R/M HNSCC patients treated with nivolumab from 2014 to 2018. Tumor size was evaluated by RECIST ver.1.1. Tumor growth rate (Gr) was defined as 3log(D0/Dpre)/t, where D0 and Dpre are the sum of the diameters of the target lesions (SumTLs) at baseline and pre-baseline, and t is time, with 1t defined as 4 weeks. RESULTS: Twenty-five patients were enrolled. Survival was significantly worse in patients with disease progression within 3 months. Outcomes appeared poorer in patients with higher pre-treatment Gr and bigger SumTLs at baseline. We therefore explored the association between prognosis, Gr and SumTLs. Recursive partitioning analysis showed that the characteristics of patients with disease progression after 3 months were Gr < 0.76 and SumTLs < 31.0 mm. Further, Gr < 0.76 and SumTLs < 31.0 mm was associated with significantly longer PFS (p = 0.01) and OS (p < 0.01). CONCLUSIONS: These results suggest that Gr and SumTLs at baseline are significantly associated with OS and PFS in R/M HNSCC patients treated with nivolumab.

Assessment of Tocilizumab (Anti-Interleukin-6 Receptor Monoclonal) as a Potential Treatment for Chronic Antibody-Mediated Rejection and Transplant Glomerulopathy in HLA-Sensitized Renal Allograft Recipients.

Extending the functional integrity of renal allografts is the primary goal of transplant medicine. The development of donor-specific antibodies (DSAs) posttransplantation leads to chronic active antibody-mediated rejection (cAMR) and transplant glomerulopathy (TG), resulting in the majority of graft losses that occur in the United States. This reduces the quality and length of life for patients and increases cost. There are no approved treatments for cAMR. Evidence suggests the proinflammatory cytokine interleukin 6 (IL-6) may play an important role in DSA generation and cAMR. We identified 36 renal transplant patients with cAMR plus DSAs and TG who failed standard of care treatment with IVIg plus rituximab with or without plasma exchange. Patients were offered rescue therapy with the anti-IL-6 receptor monoclonal tocilizumab with monthly infusions and monitored for DSAs and long-term outcomes. Tocilizumab-treated patients demonstrated graft survival and patient survival rates of 80% and 91% at 6 years, respectively. Significant reductions in DSAs and stabilization of renal function were seen at 2 years. No significant adverse events or severe adverse events were seen. Tocilizumab provides good long-term outcomes for patients with cAMR and TG, especially compared with historical published treatments. Inhibition of the IL-6-IL-6 receptor pathway may represent a novel approach to stabilize allograft function and extend patient lives.

Magnetodielectric detection of magnetic quadrupole order in Ba(TiO)Cu4(PO4)4 with Cu4O12 square cupolas.

In vortex-like spin arrangements, multiple spins can combine into emergent multipole moments. Such multipole moments have broken space-inversion and time-reversal symmetries, and can therefore exhibit linear magnetoelectric (ME) activity. Three types of such multipole moments are known: toroidal; monopole; and quadrupole moments. So far, however, the ME activity of these multipole moments has only been established experimentally for the toroidal moment. Here we propose a magnetic square cupola cluster, in which four corner-sharing square-coordinated metal-ligand fragments form a noncoplanar buckled structure, as a promising structural unit that carries an ME-active multipole moment. We substantiate this idea by observing clear magnetodielectric signals associated with an antiferroic ME-active magnetic quadrupole order in the real material Ba(TiO)Cu4(PO4)4. The present result serves as a useful guide for exploring and designing new ME-active materials based on vortex-like spin arrangements.

High molecular weight organic compounds (HMW-OCs) in severe winter haze: Direct observation and insights on the formation mechanism.

High molecular weight organic compounds (HMW-OCs), formed as secondary organic aerosols (SOA), have been reported in many laboratory studies. However, little evidence of HMW-OCs formation, in particular during winter season in the real atmosphere, has been reported. In January 2013, Beijing faced historically severe haze pollution, in which the hourly PM2.5 concentration reached as high as 974 µg m-3. Four typical haze events (HE1 to HE4) were identified, and HE2 (Jan. 9-16) was the most serious of these. Based on the hourly observed chemical composition of PM2.5 and the daily organic composition analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), we found that abundant ion peaks in m/z 200-850 appeared on heavy haze days, whereas these were negligible on a clear day, indicating the existence of HMW-OCs in the wintertime haze. A negative nonlinear correlation between HMW-OCs and O3 suggested that gas oxidation was not likely to be the dominant mechanism for HMW-OCs formation. During the heavy haze events, the relative humidity and mass ratio of H2O/PM2.5 reached as high as 80% and 0.2, respectively. The high water content and its good positive correlation with HMW-OCs indicated that an aqueous-phase process may be a significant pathway in wintertime. The evidence that acidity was much higher during HE2 (0.37 µg m-3) than on other days, as well as its strong correlation with HMW-OCs, indicated that acid-catalyzed reactions likely resulted in HMW-OCs formation during the heavy winter haze in Beijing.

Expression of ER stress markers (GRP78/BiP and PERK) in patients with tongue cancer.

The glucose-regulated protein (GRP78/BiP) and PKR-like endoplasmic reticulum kinase (PERK) plays a crucial role in the endoplasmic reticulum (ER) stress response. GRP78/BiP is highly elevated in various human cancers. Our study is to examine the clinicopathological significance of GRP78/BiP and PERK expression in patients with tongue cancer. A total of 85 tongue cancer patients were analyzed, and tumor specimens were stained by immunohistochemistry for GRP78/BiP, PERK, GLUT1, Ki-67 and microvessel density (MVD) determined by CD34.GRP78/BiP and PERK were highly expressed in 47% and 35% of all patients, respectively. GRP78/BiP disclosed a significant relationship with PERK expression, lymphatic permeation, vascular invasion, glucose metabolism and cell proliferation. The expression of GRP78/BiP was significantly higher in metastatic sites than in primary sites (79% vs. 47%, p=0.003). We found that the high expression of GRP78/BiP was proven to be an independent prognostic factor for predicting poor outcome in patients with tongue cancer. In the analysis of PFS, PERK was identified as an independent predictor. The increased GRP78/BiP expression was clarified as an independent prognostic marker for predicting worse outcome. Our study suggests that the expression of GRP78/BiP as ER stress marker is important in the pathogenesis and development of tongue cancer.

Supplemental Analysis for N-linked Sugars in Adult Pig Islets.

The pig pancreas is considered to be one of the most suitable sources of islets for clinical xenotransplantation. However, after producing α1-3galactosyltransferase knockout pigs, most of the organs of these pigs showed less antigenicity to the human body. Wild-type adult pig islets (APIs) that originally produced negligible levels of α-Gal, different from neonatal porcine islet-like cell clusters, showed a clear antigenicity to human serum. Concerning the so-called non-Gal epitopes, many studies related to glycoproteins and glycolipids are ongoing in efforts to identify them. However, our knowledge of non-Gal glycoantigens remains incomplete. In our previous study, N-glycans were isolated from APIs, and the structures of 28 of the N-glycans were detected. In this study, to identify additional structures, further analyses were performed by liquid chromatography-mass spectrometry (LC-MS). N-glycans were isolated from APIs by the method described by O'Neil et al with minor modifications and LC-MS-based structural analyses were then performed. The detected N-glycan peaks in the LC-MS spectra were selected using the FLexAnalysis software program and the structures of the glycans were predicted using the GlyocoMod Tool. The API preparation contained 11 peaks and 16 structures were then nominated as containing N-linked sugars. Among them, 5 sulfated glycans were estimated, confirming the existence of sulfate structures in N-glycans in API. In addition, these data may supplement several N-glycan structures that contain two deoxyhexose units, such as fucose, to our previous report. The data herein will be helpful for future studies of antigenicity associated with API.

Prognostic significance of GRP78/BiP expression in patients with Stage III/IV hypopharyngeal squamous cell carcinoma.

The immunoglobulin heavy chain binding protein (BiP)/glucose-regulated protein 78 (GRP78) plays an essential role in the endoplasmic reticulum (ER) stress, and GRP78/BiP is known to be highly expressed in various human neoplasms. The clinicopathological features of GRP78/BiP expression in patients with advanced hypopharyngeal squamous cell carcinoma (HSCC) remain unclear. The aim of this study is to elucidate the prognostic significance of GRP78/BiP for HSCC.A total of 68 patients with advanced HSCC (stage III/IV) were analyzed, and tumor specimens were stained with immunohistochemistry for GRP78/BiP, Ki-67, and microvessel density (MVD), as determined through CD34 and p53 levels. GRP78/BiP was highly expressed in 80.8% (55/68) of all patients. The expression level of GRP78/BiP disclosed no significant relationship with any variables. Multivariate analysis confirmed that low expression of GRP78/BiP was an independent prognostic factor for predicting poor overall survival and progression-free survival in patients with advanced HSCC. The decreasing expression of GRP78/BiP was identified as a significant predictor related to shorter survival duration after surgery for advanced HSCC. Our study suggests that the reduced expression of GRP78/BiP contributes to worse survival for patients with advanced head and neck cancer.

Liver Transplantation in a Patient With CD40 Ligand Deficiency and Hyper-IgM Syndrome: Clinical and Immunological Assessments.

Monoclonal antibodies that disrupt CD40-CD40 ligand (CD40L) interactions are likely to have use in human transplantation. However, the extent of the immunosuppressive effects of CD40-CD40L blockade in humans is unknown. Hyper-IgM syndrome (HIGM) is a rare primary immunodeficiency syndrome characterized by defects in the CD40-CD40L pathway, severe immune deficiency (IgG), and high or normal IgM levels. However, the effects of CD40L deficiency on T- and natural killer (NK)-cell function is not established. Here, we present a patient with HIGM syndrome who underwent liver transplantation for hepatitis C virus infection. Posttransplantation, NK-cell antibody-dependent cytokine release (γ-interferon) to alloantigens and T cell responses to viral antigens and mitogens were assessed and showed normal CD4+ , CD8+ , and NK-cell responses. We also examined antibody-dependent cellular cytotoxicity against a CD40+ and HLA-expressing cell line. These experiments confirmed that the patient's NK cells were equivalent to those of normal subjects in mediating antibody-dependent cellular cytotoxicity despite the absence of CD40-CD40L interactions. Mitogenic stimulation of the patient's peripheral blood mononuclear cells showed no expression of CD40L on T and NK cells compared with increased expression in normal subjects. Taken together, these data suggest that absence of CD40L expression is responsible for aberrant B cell immunity but had little impact on NK- and T cell immune responses in vitro.

JC polyomavirus viremia and progressive multifocal leukoencephalopathy in human leukocyte antigen-sensitized kidney transplant recipients desensitized with intravenous immunoglobulin and rituximab.

BACKGROUND: Desensitization (DES) with intravenous immunoglobulin (IVIG) + rituximab is effective, safe, and increases the transplantation rate in human leukocyte antigen-sensitized patients. However, reports of progressive multifocal leukoencephalopathy (PML) caused by JC polyomavirus (JCPyV) in autoimmune patients treated with rituximab is concerning. Here, we report on the JCPyV viremia and PML status in kidney transplant patients with/without DES (non-DES). METHODS: In total 1195 and 699 DNA samples from plasma in 117 DES (78% lymphocyte-depleting [LyD] induction) and 100 non-DES patients (45% LyD), respectively, were submitted for JCPyV-polymerase chain reaction. Results were compared in both groups. RESULTS: No patients in either DES or non-DES developed PML or presented with any neurological symptoms. The JCPyV viremia rate was similar in DES and non-DES patients (3/117 vs. 9/100, P = 0.07). The JCPyV levels were low (median peak levels, 1025 copies/mL) and JCPyV viremia was observed only once during the study period in most patients. All 3 DES patients with JCPyV(+) received 1 dose rituximab and no DES patients with >1 dose rituximab showed JCPyV(+). All 3 JCPyV(+) DES patients received LyD induction, while only 2 of 9 JCPyV(+) non-DES patients did so, and the remaining 7 received non-LyD or no induction. JCPyV in leukocyte was mostly negative in DES and non-DES patients. Immunosuppression in patients with or without JCPyV(+) was similar. BK polyomavirus viremia was observed more commonly in patients with JCPyV(+) than in those without (P < 0.02). CONCLUSIONS: Patients with IVIG + rituximab DES followed by transplantation with LyD induction and additional rituximab rarely show JCPyV viremia and appear at low risk for PML.

Prediction of low-frequency structure-borne sound in concrete structures using the finite-difference time-domain method.

Due to limitations of computers, prediction of structure-borne sound remains difficult for large-scale problems. Herein a prediction method for low-frequency structure-borne sound transmissions on concrete structures using the finite-difference time-domain scheme is proposed. The target structure is modeled as a composition of multiple plate elements to reduce the dimensions of the simulated vibration field from three-dimensional discretization by solid elements to two-dimensional discretization. This scheme reduces both the calculation time and the amount of required memory. To validate the proposed method, the vibration characteristics using the numerical results of the proposed scheme are compared to those measured for a two-level concrete structure. Comparison of the measured and simulated results suggests that the proposed method can be used to simulate real-scale structures.

Prognostic significance of amino-acid transporter expression (LAT1, ASCT2, and xCT) in surgically resected tongue cancer.

BACKGROUND: Amino-acid transporters are necessary for the tumour cell growth and survival, and have a crucial role in the development and invasiveness of cancer cells. But, it remains unclear about the prognostic significance of L-type amino-acid transporter 1 (LAT1), system ASC amino-acid transporter-2 (ASCT2), and xCT expression in patients with tongue cancer. We conducted the clinicopathological study to investigate the protein expression of these amino-acid transporters in tongue cancer. METHODS: Eighty-five patients with surgically resected tongue cancer were evaluated. Tumour sections were stained by immunohistochemistry for LAT1, ASCT2, xCT, 4F2hc/CD98hc (4F2hc), Ki-67, and microvessel density (MVD) determined by CD34, and p53. RESULTS: L-type amino-acid transporter 1 and 4F2hc were highly expressed in 61% (52 out of 85) and 45% (38 out of 47), respectively. ASC amino-acid transporter-2 and xCT were positively expressed in 59% (50 out of 85) and 21% (18 out of 85), respectively. The expression of both LAT1 and ASCT2 was significantly associated with disease staging, lymph-node metastasis, lymphatic permeation, 4F2hc expression and cell proliferation (Ki-67). xCT expression indicated a significant association with advanced stage and tumour factor. By univariate analysis, disease staging, lymphatic permeation, vascular invasion, LAT1, ASCT2, 4F2hc, and Ki-67 had a significant relationship with overall survival. Multivariate analysis confirmed that LAT1 was an independent prognostic factor for predicting poor prognosis. CONCLUSIONS: L-type amino-acid transporter 1 and ASCT2 can serve as a significant prognostic factor for predicting worse outcome after surgical treatment and may have an important role in the development and aggressiveness of tongue cancer.

Long-term safety of living kidney donors aged 60 and older.

In Japan, kidney transplantation procedures are usually dependent upon live donors. As the recipient ages have been increasing, so has there been a corollary increase in the age of the live donors. Despite this being controversial, the use of older donors is becoming increasingly common. The purpose of our study was to evaluate the long-term safety of accepting older living kidney donors and graft survival rates. We retrospectively analyzed long-term donor outcomes for consecutive patients at our institution between January 1990 and December 2011. Older live kidney donors were defined as ≥ 60 years and younger live kidney donors were defined as <60 years old. Thirty-three were ≥ 60 years and 55 donors were <60 years. The mean follow-up term was 7 years and 4 months. Predonation, older donors had a lower estimated glomerular filtration rate (eGFR) level (77.1 ± 9.5 mL/min/1.73 m(2)) than younger donors (85.8 ± 14.6 mL/min/1.73 m(2); P < .01). More older donors had a history of hypertension (42.4% vs 9.1%; P < .01). In both groups, eGFR levels decreased about 40% immediately after nephrectomy. Residual renal function though was stable on long-term follow-up. The incidence of de novo hypertension and proteinuria after nephrectomy was not different between the 2 groups. In older donors, there were no perioperative complications that required extended hospital stays. Graft survival over a period of 10 years was similar in both groups. In our study, donor age had no influence on the deterioration of renal function after nephrectomy. Regardless of age, careful evaluation and follow-up are important for the donor's long-term safety after donation.

Gender difference in tooth autotransplantation with complete root formation: a retrospective survey.

Gender-related risk factors in the survival of transplanted teeth with complete root formation have not yet been identified. The purpose of this study was to investigate gender differences in tooth autotransplantation at dental clinics. We asked participating dentists to provide information on transplantations they had undertaken from 1 January 1990 to 1931 December 2010. The data were screened to exclude patients who underwent more than one transplantation, smokers or those whose smoking habits were unknown, patients under 30 or who were 70 years old and over, cases where the transplanted teeth had incomplete root formation or multiple roots and those with fewer than 20 present teeth post-operation. We analysed 73 teeth of 73 males (mean age, 47.2 years) and 106 teeth of 106 females (mean age, 45.3 years) in this study. The cumulative survival rate and mean survival time were calculated using the Kaplan-Meier method. The cumulative survival rate for males was 88.3% at the 5-year mark, 64.8% at 10 years and 48.6% at 15 years; for females, it was 97.2% at the 5-year mark, 85.9% at 10 years and 85.9% at 15 years. A log-rank test indicated the difference between males and females to be significant (P = 0.011). There was also a significant difference in the main causes for the loss of transplanted teeth: males lost more transplanted teeth due to attachment loss than females (P < 0.05). These results indicate that males require more attention during the autotransplantation process, particularly at the stage of pre-operation evaluation and that of follow-up maintenance.

Influence of age on tooth autotransplantation with complete root formation.

The aim of this study was to investigate risk factors with age in the long-term prognosis of autotransplantation of teeth with complete root formation at dental clinics. Participating dentists were asked to provide information on transplantations they had undertaken from 1 January 1990 to 31 December 2010. Data on a total of 708 teeth from 637 patients were collected. The data were screened to exclude patients who were under 25 or 70 years of age and over, those who were smokers or whose smoking habits were unknown, those whose transplanted teeth had incomplete root formation or multiple roots and those with fewer than 25 present teeth post-operation. The participants in this study were 71 men (74 teeth) and 100 women (107 teeth) ranging from 25 to 69 years of age. Third molars were used as donor teeth in 89·0% of the cases. The participants were divided into three age groups of 25-39, 40-54 and 55-69. Survival analysis was conducted using the Kaplan-Meier method, and a log-rank test revealed that there were no significant differences in age groups for men or women. Cox regression analysis indicated that the survival of transplanted teeth was not influenced by age. However, although not statistically significant, the clinical success rate was lower in the 55-69-year-old group than that in the younger groups. These results indicate that if suitable donor teeth are available and the conditions are right, autotransplantation is a viable treatment for missing teeth regardless of the age of the patient.

Comparison of prognosis of separated and non-separated tooth autotransplantation.

The aim of this study was to compare the prognosis of separated and non-separated tooth autotransplantation of the upper first and second molars with complete root formation undertaken at dental clinics. The participating dentists were requested to provide information on transplantations they had undertaken from 1 January 1990 to 31 December 2010. Data on a total of 708 teeth from 637 patients were collected. This study analysed 35 separated teeth and 22 non-separated teeth of 47 participants ranging from 27 to 76 years of age (mean age: 55·0 years) after data screening and elimination. The cumulative post-transplantation survival rate at 10 years was 77·1% for separated teeth and 63·6% for non-separated teeth as calculated with the Kaplan-Meier method. There were no significant differences between separated teeth and non-separated teeth in a log rank test (P = 0·687). Separated-tooth autotransplantation can help fill narrow recipient sites and increase occlusal supporting zones, but the clinical success rate was only 48·6%. Although transplantation of teeth with complete root formation has limited prognosis, transplantation of upper first and second molars, whether separated or non-separated, is a viable option to replace missing teeth.

Risk factors affecting third molar autotransplantation in males: a retrospective survey in dental clinics.

The aim of this study was to investigate the risk factors affecting long-term prognosis of autotransplantation of third molars with complete root formation in males at dental clinics. Participating dentists were requested to provide information on transplantations they had undertaken from 1 January 1990 to 31 December 2010. Data on a total of 708 teeth from 637 patients were collected. After data screening and elimination, participants of this study consisted of 183 teeth of 171 males ranging from 20 to 72 years of age (mean age, 44·8 years). The cumulative survival rate was 86·0% at the 5-year mark, 59·1% at 10 years and 28·0% at 15 years. The mean survival time was 134·5 months, as calculated by the Kaplan-Meier method. Single factor analysis using the log-rank test showed that the following factors had significant influence (P < 0·05) on survival of transplanted teeth: periodontal disease as the reason for recipient site tooth extraction, fewer than 25 present teeth and Eichner index Groups B1 to C. Cox regression analysis examined five factors: age, smoking habit, recipient site extraction caused by periodontal disease, fewer than 25 present teeth and Eichner index. This analysis showed that two of these factors were significant: fewer than 25 present teeth was 2·63 (95% CI, 1·03-6·69) and recipient site extraction caused by periodontal disease was 3·80 (95% CI, 1·61-9·01). The results of this study suggest that long-term survival of transplanted teeth in males is influenced not only by oral bacterium but also by occlusal status.

IFNγ production by NK cells from HLA-sensitized patients after in vitro exposure to allo-antigens.

Using a novel cytokine flow cytometry test (allo-CFC), we have previously shown that incubation of allogeneic cells with peripheral blood from highly-HLA sensitized (HS) patients results in reproducible gamma-interferon (IFNγ production in CD3(-) cells, and high (+) allo-CFC levels correlated with risk for antibody-mediated rejection (AMR). Here we report on identification of the cells and mechanisms responsible. The allo-CFC with/without modification was performed using blood from HS or normal individuals. IFNγ producing cells were CD3(-)/CD19(-), but CD3(-)/CD56(+). In vitro and in vivo B cell-depletion did not affect IFNγ production, demonstrating NK cells as the cells responsible for IFNγ production. NK cells from allo-CFC(+) or (-) individuals released significant amounts of IFNγ against target cells treated with serum from allo-CFC(+) individuals, but not allo-CFC(-) individuals. IFNγ release was abrogated by protein A/G treatment of the pretreated target cells, suggesting mediation by antibodies via FcγRIIIa (CD16). In conclusion, NK cell IFNγ release after allo-antigen exposure is mediated primarily through antibody-dependent cellular cytotoxicity (ADCC)-like mechanisms, suggesting that NK cells may be partially responsible for graft injury during AMR including C4d(-) AMR via ADCC, and could be a potential target for modification of this process.

A retrospective survey of autotransplantation of teeth in dental clinics.

The aim of this study was to investigate the usage of tooth autotransplantation in dental clinics which offer the treatment and evaluate its practicality. Participating dentists were requested to provide information on transplantations they had undertaken from 1 January 1990 to 31 December 2010. A total of 614 teeth from 552 patients (37 dentists) ranging in age from 17 to 79 (mean age: 44·1) were examined. Cumulative survival rate and mean survival time were calculated using the Kaplan-Meier method, and log rank test was used for analysis of factors. The mean number of autotransplantation patients per clinic per year was 1·4. Upper third molars constituted 36·8% of donor teeth, while 37·1% were lower third molars. The lower first molar region was the most common recipient site at 32·6%, followed by the lower second molar region (28·0%). Prosthodontic treatment of transplanted teeth involved coverage with a single crown (72·5%) and abutment of bridge (18·9%). A total of 102 transplanted teeth were lost owing to complications such as attachment loss (54·9%) and root resorption (25·7%). The cumulative survival rate in cases where donor teeth had complete root formation was 90·1% at 5 years, 70·5% at 10 years and 55·6% at 15 years. The mean survival time was 165·6 months. Older age was a significant risk factor (P < 0·05) for survival. In cases where suitable donor teeth are available, autotransplantation of teeth may be a plausible treatment option for dealing with missing teeth in dental clinics.