Impact of nutrition and inflammation indicators on peritoneal dialysis initiation and management

BACKGROUND

The clinical significance of nutrition and inflammation in dialysis patients is well established. This study aimed to evaluate the association between prognosis and indicators of nutrition and inflammation.

METHODS

A total of 253 consecutive patients who underwent peritoneal dialysis (PD) as primary renal replacement therapy at our institute between 2006 and 2021 were included. We retrospectively reviewed the patient's medical charts and obtained their clinical information. Nine nutritional and two inflammatory indicators were assessed. Patient outcomes were investigated, and predictive factors were explored.

RESULTS

The median age and follow-up period were 65 years and 54 months, respectively. Most nutritional indicators and C-reactive protein (CRP) levels showed a significant correlation with residual renal function. Multivariate analysis revealed that the survival index, nutritional risk index for Japanese hemodialysis patients, and CRP levels were independent indicators of patient survival (P < 0.001, P = 0.034, and P = 0.005, respectively) and cardiovascular disease-free survival (P = 0.009, P = 0.04, and P = 0.017, respectively). Patients with a survival index < 19 and CRP ≥ 0.5 had a high risk of mortality and cardiovascular death (P < 0.0001 and P = 0.0002, respectively).

CONCLUSIONS

Our findings suggest that indicators of nutrition and inflammation play important roles in predicting patient outcomes. Further research is warranted to establish optimal management strategies for patients on PD.

Enfortumab vedotin following platinum-based chemotherapy and immune checkpoint inhibitors for advanced urothelial carcinoma: response, survival and safety analysis from a multicentre real-world Japanese cohort

OBJECTIVE

Real-world evidence regarding enfortumab vedotin for unresectable or metastatic urothelial carcinoma is scarce, particularly in Japan. We investigated real-world data focusing on patient background, previous treatments, response, survival and adverse events in patients receiving enfortumab vedotin.

METHODS

A multicentre database was used to register 556 patients diagnosed with metastatic urothelial carcinoma from 2008 to 2023; 34 patients (6.1%) treated with enfortumab vedotin were included. Best radiographic objective responses were evaluated using the Response Evaluation Criteria in Solid Tumors (v1.1) during treatments. Overall survival and progression-free survival were estimated (Kaplan-Meier method). Toxicities were reported according to the Common Terminology Criteria for Adverse Events, version 5.0. The relative dose intensity, which could impact oncological outcomes, was calculated.

RESULTS

The median number of enfortumab vedotin therapy cycles was 5. The best objective response to enfortumab vedotin was partial response, stable disease and progressive disease in 19 (56%), 5 (15%) and 10 (29%) patients, respectively. The median overall survival and progression-free survival after the first enfortumab vedotin dose were 16 and 9 months, respectively. No significant relationship was observed between survival outcomes after enfortumab vedotin initiation and the enfortumab vedotin relative dose intensity. The median overall survival from first-line platinum-based chemotherapy initiation was 42 months. Twenty-six (76%) patients experienced any grade of enfortumab vedotin-related toxicities; eight (24%) experienced Grades 3-4 toxicities, the most common being skin toxicity (any grade, 47%; Grades 3-4, 12%).

CONCLUSIONS

Here, we report real-world evidence for enfortumab vedotin therapy in Japan. Tumour responses and safety profiles were comparable with those of clinical trials on this novel treatment.

Impact of Complete Surgical Resection of Metastatic Lesions in Patients with Advanced Renal Cell Carcinoma in the Era of Tyrosine Kinase Inhibitors and Immune Checkpoint Inhibitors

Complete metastasectomy (CM) in metastatic renal cell carcinoma (mRCC) has demonstrated efficacy in the cytokine era, but its effectiveness in the era of tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) remains unclear. A multi-institutional database included clinicopathological data of 367 patients with mRCC. Patients were divided into two groups: the CM group and the non-CM group. These two groups were compared before and after propensity score matching (PSM). Cox proportional hazard models were used to detect factors associated with disease-free survival (DFS) and overall survival (OS) from mRCC diagnosis. The CM group showed a significant association with longer overall survival compared to the non-CM group in the PSM-unadjusted cohorts (p < 0.001, hazard ratio 0.49, 95% confidence interval 0.35-0.69), but no superiority was noted in the adjusted cohorts. The median DFS after CM was 24 months, with no significant differences based on relapse timing. Notably, the international metastatic RCC database consortium risk categories and metastatic burden were associated with DFS. This study supports the potential of CM in mRCC management during the TKI/ICI era, although limitations including sample size and selection bias need to be considered.

Direct screening for effective shRNA with a single mismatch in human cells without laborious cloning

We have devised a method for the direct screening of efficient short hairpin (sh)RNA molecules in human cells, eliminating the need for the time-consuming process of cloning in Escherichia coli. Our screening suggested that single mismatches to shRNAs can significantly alter their activity.

[Efficacy of Recombinant Thrombomodulin for Sepsis-Associated Disseminated Intravascular Coagulation Caused by Urinary Tract Infections]

Severe urinary tract infections occasionally cause sepsis and disseminated intravascular coagulation (DIC). We examined the efficacy of recombinant thrombomodulin (rTM) for treating DIC caused by urosepsis. We enrolled 40 patients who were diagnosed with DIC caused by urosepsis at our hospital between April 2018 and May 2022. Twenty-six patients were treated with rTM (rTM group), while 14 patients did not receive rTM (non-rTM group). The DIC score before treatment in the rTM group was significantly higher than that in the non-rTM group (P＜0.01). There was no significant difference in disease-specific survival between the two groups. There was a significant improvement in DIC scores on days 1-3 after administering rTM. However, the duration of DIC in the rTM group was significantly longer than that in the non-rTM group (P＝0.038). The administration of rTM may have benefits in patients with DIC caused by urosepsis.

Clinical impact of catheter insertion for peritoneal dialysis on patient survival and catheter-related complications

OBJECTIVES

The stepwise initiation of peritoneal dialysis (PD) using Moncrief and Popovich's technique (SMAP) for catheter insertion is recommended for the systemic introduction of PD and prevention of catheter-related infections. In this study, we investigated patient outcomes in patients who underwent insertion of a PD catheter with a direct method versus the SMAP method.

METHODS

We enrolled 295 consecutive patients who underwent PD as a primary renal replacement therapy and underwent insertion of a PD catheter at our institute between 2006 and 2021. We retrospectively reviewed their data and investigated patient outcomes, including mortality and PD catheter-related complications.

RESULTS

Median age at PD induction was 65 years in the direct insertion group and 65 years in the SMAP group (P = 0.80). The rate of PD introduction after emergency hemodialysis was significantly higher in the direct insertion group than in the SMAP group (P < 0.001). There was no significant difference in survival between the direct insertion and SMAP groups during the median follow-up period of 54 months (P = 0.12). Additionally, patients who transitioned to hemodialysis or kidney transplantation after PD showed significantly longer survival (P < 0.001). The incidence of PD catheter-related complications was not significantly different between the two groups. A body mass index ≥ 23 kg/m2 was an independent risk factor for peritonitis and exit-site infection (P = 0.006 and P = 0.011, respectively).

CONCLUSIONS

Planned sequential renal replacement therapy including hybrid hemodialysis, complete hemodialysis, and kidney transplantation after PD is important for improving patient outcomes. PD catheter insertion by SMAP may not be mandatory in our clinical practice.

Is the LRINEC score useful for predicting necrotizing fasciitis as a complication of MRONJ?

INTRODUCTION

Necrotizing fasciitis as a complication of medication-related osteonecrosis of the jaw (MRONJ), which we named "ONJ-NF", has been sometimes reported. This study aimed to investigate the usefulness of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score for predicting ONJ-NF.

MATERIALS AND METHODS

We included patients with acute MRONJ who required hospitalization at a single institution from April 2013 to June 2022. They were divided into two groups: patients with ONJ-NF and those with severe cellulitis as a complication of MRONJ, which we named "ONJ-SC." LRINEC scores were compared between the groups and the cut-off value of the score was set by creating a receiver operating characteristic curve.

RESULTS

Eight patients with ONJ-NF and 22 patients with ONJ-SC were included. The LRINEC score was significantly higher in patients with ONJ-NF (median: 8.0 points, range 6-10 points) than in those with ONJ-SC (median: 2.5 points, range 0-6 points). A LRINEC score of ≥ 6 points had a sensitivity of 100.0%, a specificity of 77.3%, and an area under the curve of 0.97. Among 6 parameters of LRINEC score, only C-reactive protein (CRP) and white blood cell count (WBC) had significant differences between two groups. Most of the patients with ONJ-NF were rescued by antibiotic therapy and surgical drainage including debridement of necrotic tissues, but unfortunately, one patient did not survive.

CONCLUSION

Our results suggested that the LRINEC score may be a useful diagnostic tool to predict ONJ-NF but valuating only CRP and WBC may be sufficient particularly in patients with osteoporosis.

[Adrenal Hemangiomatous Endothelial Cyst That was Difficult to Differentiate from Adrenal Malignant Tumor: A Case Report]

A 65-year-old woman was referred to our hospital for fever and diagnosed with pyelonephritis. Abdominal computed tomography showed a right adrenal tumor incidentally, that was 6.5 cm in diameter. We could not rule out malignant disease by magnetic resonance imaging examination and performed resection of the right adrenal tumor. The histopathological examination revealed an adrenal hemangiomatous endothelial cyst, and there was no evidence of malignancy. It was difficult to differentiate between adrenal cyst and adrenal cancer in preoperative diagnostic imaging because the tumor contained hemorrhage and necrotic tissue.

Composite pheochromocytoma associated with neurofibromatosis type 1

Introduction

Composite pheochromocytoma is a rare tumor, occurring in only 3% of pheochromocytomas. We report a case of composite pheochromocytoma with neurofibromatosis type 1.

Case presentation

A 42-year-old man was referred to our department for further evaluation of an incidentally detected right adrenal tumor. He was a patient at another hospital for neurofibromatosis type 1. The serum and urinary catecholamine levels exceeded the normal range. Abdominal computed tomography and magnetic resonance imaging showed a 2.8 cm diameter right adrenal tumor, and 123I-metaiodobenzyguanidine scintigraphy showed radioisotope uptake. He was diagnosed with pheochromocytoma and underwent a right laparoscopic adrenalectomy. Histopathological examination revealed that the tumor consisted of a pheochromocytoma and ganglioneuroma. The final diagnosis was composite pheochromocytoma-ganglioneuroma. Five years after surgery, no recurrence was observed.

Conclusion

Preoperative diagnosis of composite pheochromocytoma-ganglioneuroma is difficult; therefore, histopathological examination is necessary for a definitive diagnosis. Pheochromocytoma management requires lifelong follow-up.

Switch-maintenance avelumab immunotherapy following first-line chemotherapy for patients with advanced, unresectable or metastatic urothelial carcinoma: the first Japanese real-world evidence from a multicenter study

OBJECTIVE

To develop the first Japanese real-world evidence of switch-maintenance avelumab in advanced, unresectable or metastatic urothelial carcinoma (aUC).

METHODS

A multicenter-derived database registered 505 patients diagnosed with aUC between 2008 and 2021. Of these, 204 patients (40%) were selected and stratified according to the type of therapy used: maintenance avelumab group (27 [5.3%]), second-line (2 L) pembrolizumab group (103 [20%]) and 2 L cytotoxic chemotherapy group (74 [15%]). The progression-free survival and overall survival from the initiation of following therapy were compared. Tumor response was evaluated based on the Response Evaluation Criteria in Solid Tumors guideline v1.1 during the treatment period. A detailed analysis was performed in the maintenance avelumab group to investigate possible factors associated with response to avelumab therapy.

RESULTS

The maintenance avelumab group had a longer overall survival, not progression-free survival, compared with the other two treatment groups. The median treatment-free interval between the last dose of first-line (1 L) chemotherapy and the initiation of avelumab therapy was 6 weeks (range, 3-22). Disease control rate of maintenance avelumab therapy in patients with a treatment-free interval of ≤6 weeks was higher than that in patients with a treatment-free interval of >6 weeks (77 vs 40%, P = 0.029). The patients showing objective response to 1 L chemotherapy were less likely to experience tumor relapse (4 of 19) after the initiation of avelumab therapy compared with those showing stable disease (7 of 8).

CONCLUSIONS

Objective response to 1 L chemotherapy and early induction of maintenance avelumab therapy may be associated with increased benefit from maintenance avelumab therapy.

Clinical significance of limited and extended pelvic lymph node dissection during robot-assisted radical prostatectomy for patients with localized prostate cancer: A retrospective, propensity score matching analysis

OBJECTIVES

We investigated the diagnostic and therapeutic benefits of limited or extended pelvic lymph node dissection during a robot-assisted radical prostatectomy for localized prostate cancer.

METHODS

Diagnostic and therapeutic benefits were assessed according to the rates of pN1 and biochemical recurrence, respectively. The primary outcome was the biochemical recurrence-free rate, and secondary outcomes included the diagnostic and therapeutic benefits of pelvic lymph node dissection.

RESULTS

A total of 534 patients were analyzed. Out of the 534 patients, 207 (38.8%) received limited pelvic lymph node dissection while 134 (25.1%) received extended dissection. There were 297 patients with a Briganti index ≥5%. Extended dissections yielded significantly more resected lymph nodes (p < 0.0001), and 72.2% of cases of pN1 were located outside the obturator. The incidence rate of pN1 was 6.1%, and performance of extended lymph node dissection was an independent predictor for pN1 (odds ratio 9.0, 95% confidence interval 2.5-33.1). The rate of biochemical recurrence was 14.9%, and Cox proportional hazards regression analysis of the propensity score matched population revealed that patients with high or very-high risk tended to benefit from limited lymph node dissection (hazard ratio 8.4, 95% confidence interval 0.8-82.3) while the therapeutic benefit of extended dissection was unclear by comparison.

CONCLUSIONS

Extended pelvic lymph node dissection significantly improves diagnostic accuracy; however, the therapeutic benefit of pelvic lymph node dissection was not observed in this study.

Calorie restriction alters the mechanisms of radiation-induced mouse thymic lymphomagenesis

Calorie restriction (CR) suppresses not only spontaneous but also chemical- and radiation-induced carcinogenesis. Our previous study revealed that the cancer-preventive effect of CR is tissue dependent and that CR does not effectively prevent the development of thymic lymphoma (TL). We investigated the association between CR and the genomic alterations of resulting TLs to clarify the underlying resistance mechanism. TLs were obtained from previous and new experiments, in which B6C3F1 mice were exposed to radiation at 1 week of age and fed with a CR or standard (non-CR) diet from 7 weeks throughout their lifetimes. All available TLs were used for analysis of genomic DNA. In contrast to the TLs of the non-CR group, those of the CR group displayed suppression of copy-neutral loss of heterozygosity (LOH) involving relevant tumor suppressor genes (Cdkn2a, Ikzf1, Trp53, Pten), an event regarded as cell division-associated. However, CR did not affect interstitial deletions of those genes, which were observed in both groups. In addition, CR affected the mechanism of Ikzf1 inactivation in TLs: the non-CR group exhibited copy-neutral LOH with duplicated inactive alleles, whereas the CR group showed expression of dominant-negative isoforms accompanying a point mutation or an intragenic deletion. These results suggest that, even though CR reduces cell division-related genomic rearrangements by suppressing cell proliferation, tumors arise via diverse carcinogenic pathways including inactivation of tumor suppressors via interstitial deletions and other mutations. These findings provide a molecular basis for improved prevention strategies that overcome the CR resistance of lymphomagenesis.

Effects on Life Expectancy of Treatment Decisions in Patients With Non-metastatic Prostate Cancer

BACKGROUND/AIM

Life expectancy is considered in treatment decision-making for non-metastatic prostate cancer (PCa). We explored the factors related to overall survival (OS) and investigated the association between OS and life expectancy in patients with non-metastatic PCa according to various treatment modalities.

PATIENTS AND METHODS

This retrospective study included 714 patients with non-metastatic PCa between 2006 and 2010 at our institute. The treatment modalities were classified as follows: radical prostatectomy (RP), androgen deprivation therapy (ADT), brachytherapy (BT) and external beam radiation therapy (EBRT). We defined life expectancy according to an abridged life table published by the Ministry of Health, Labour and Welfare in Japan.

RESULTS

The median age and initial prostate-specific antigen levels at treatment were 71 years and 8.8 ng/mL, respectively. Advanced age, Charlson comorbidity index (CCI) ≥1, cT3a stage and ADT were independent poor prognostic factors for OS. OS and life expectancy did not significantly differ in all patients (p=0.32) and in the National Comprehensive Cancer Network (NCCN) high-risk group (p=0.059). In patients with a life expectancy of <10 years, the OS was significantly shorter than life expectancy (p<0.001).

CONCLUSION

Patients with non-metastatic PCa may live beyond their life expectancy regardless of the type of therapy and NCCN risk classification, and patients with a life expectancy of <10 years may benefit from BT rather than ADT and EBRT.

Relationship between oral health and prognosis in patients with empyema: Single center retrospective study with propensity score matching analysis

BACKGROUND

Empyema is a life-threatening infection often caused by oral microbiota. To the best of our knowledge, no reports have investigated the association between the objective assessment of oral health and prognosis in patients with empyema.

MATERIALS AND METHODS

A total of 63 patients with empyema who required hospitalization at a single institution were included in this retrospective study. We compared non-survivors and survivors to assess risk factors for death at three months, including the Renal, age, pus, infection, diet (RAPID) score, and Oral Health Assessment Tool (OHAT) score. Furthermore, to minimize the background bias of the OHAT high-score and low-score groups determined based on the cut-off value, we also analyzed the association between the OHAT score and death at 3 months using the propensity score matching method.

RESULTS

The 3-month mortality rate was 20.6% (13 patients). Multivariate analysis showed that a RAPID score ≥5 points (odds ratio (OR) 8.74) and an OHAT score ≥7 points (OR 13.91) were significantly associated with death at 3 months. In the propensity score analysis, a significant association was found between a high OHAT score (≥7 points) and death at 3 months (P = 0.019).

CONCLUSION

Our results indicated that oral health assessed using the OHAT score may be a potential independent prognostic factor in patients with empyema. Similar to the RAPID score, the OHAT score may become an important indicator for the treatment of empyema.

Efficacy of pembrolizumab rechallenge for metastatic urothelial carcinoma

Introduction

Before the approval of enfortumab vedotin, no standard treatment was available as the salvage treatment for patients with metastatic urothelial carcinoma who had failed second‐line or later pembrolizumab. Pembrolizumab rechallenge is one of the options for these patients, but there is limited evidence on the effectiveness of pembrolizumab rechallenge. We report three patients with metastatic urothelial carcinoma treated with pembrolizumab rechallenge and discuss rechallenge of immune checkpoint inhibitors in other malignancies.

Case presentation

This study included three cases treated with pembrolizumab rechallenge with the age of 54 (Case 1), 78 (Case 2), and 67 (Case 3) years old. A complete response to the prior pembrolizumab was observed only in Case 1. However, no patients responded to the pembrolizumab rechallenge.

Conclusion

Pembrolizumab rechallenge is not recommended in the current clinical setting of metastatic urothelial carcinoma, even for patients who showed complete response to the prior pembrolizumab.

Post-Irradiation Thymic Regeneration in B6C3F1 Mice Is Age Dependent and Modulated by Activation of the PI3K-AKT-mTOR Pathway

Simple Summary

Because children have a long life expectancy relative to adults and their tissues and organs are growing and developing rapidly, the risk of radiation carcinogenesis for children is considered higher than that for adults. However, the underlying mechanism(s) is unclear. To uncover the mechanism, we previously revealed that principal causative genes in mouse thymic lymphomas arising in irradiated infants or adults as Pten or Ikzf1, respectively, suggesting that cells with mutation in these genes might be the origin of lymphomas arising after irradiation depending on age at exposure. Here, we clarified the age-dependent differences in thymus-cell dynamics in mice during the initial post-irradiation period. Our results demonstrate that the dynamics of thymocytes during the post-irradiation period depends on the age at exposure. For irradiated infants in particular, the number of proliferating cells increase dramatically, and this correlate with activation of the PI3K-AKT-mTOR pathway. Thus, we conclude that the PI3K-AKT-mTOR pathway in infants contributed, at least in part, to thymus-cell dynamics through the modification of cell proliferation and survival after irradiation, which may be associated with the risk of Pten mutation-associated thymic lymphoma.

Abstract

The risk of radiation-induced carcinogenesis depends on age at exposure. We previously reported principal causative genes in lymphomas arising after infant or adult exposure to 4-fractionated irradiation as Pten or Ikzf1, respectively, suggesting that cells with mutation in these genes might be the origin of lymphomas arising after irradiation depending on age at exposure. Here, we clarified the age-dependent differences in thymus-cell dynamics in mice during the initial post-irradiation period. The thymocyte number initially decreased, followed by two regeneration phases. During the first regeneration, the proportion of phosphorylated-AKT-positive (p-AKT⁺) cells in cell-cycle phases S+G2/M of immature CD4⁻CD8⁻ and CD4⁺CD8⁺ thymocytes and in phases G0/G1 of mature CD4⁺CD8⁻ and CD4⁻CD8⁺ thymocytes was significantly greater in irradiated infants than in irradiated adults. During the second regeneration, the proportion of p-AKT⁺ thymocytes in phases G0/G1 increased in each of the three populations other than CD4⁻CD8⁻ thymocytes more so than during the first regeneration. Finally, PI3K-AKT-mTOR signaling in infants contributed, at least in part, to biphasic thymic regeneration through the modification of cell proliferation and survival after irradiation, which may be associated with the risk of Pten mutation-associated thymic lymphoma.

Establishing a ready biodegradability test system using OxiTop® to evaluate chemical fate in a realistic environment

The purpose of this study is to propose the use of OxiTop® for measuring biochemical oxygen demand (BOD) under the Japanese Chemical Substances Control Law in order to properly evaluate chemical fate in a real environment. In our previous study, the biodegradation of test chemicals was accelerated by both adsorbing the chemical to silica gel with chloroform and increasing the medium volume from 300 to 3900 mL in the OECD 301F test using a coulometer. However, the biodegradability of these chemicals could not be evaluated based on BOD due to chloroform residue in the silica gel, or the medium volume could not be increased further due to the oven size of the coulometer. In this study, we established an evaluation system using OxiTop® based on BOD by increasing the medium volume to 9000 mL. Based on triplicate testing, increasing the medium volume accelerated biodegradation and decreased variation in BOD.

The characteristics of oro-cervical necrotizing fasciitis-Comparison with severe cellulitis of oro-cervical region and necrotizing fasciitis of other body regions

Background

Necrotizing fasciitis (NF) is an acute and life-threatening soft-tissue infection however rarely seen in oro-cervical region. Therefore, the details of oro-cervical NF (OCNF) are not well known. The purpose of this study was to investigate the characteristics of OCNF by comparing it with severe cellulitis of oro-cervical region (OCSC) or NF of other body regions (e.g., limb, perineum, and trunk) (BNF), respectively.

Materials and methods

At first, various risk factors for OCNF in oro-cervical severe infection (OCSI; composed of OCNF and OCSC), including neutrophil-to-lymphocyte ratio (NLR) and Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score, were investigated by univariate and multivariate analyses. Next, the differences between OCNF and BNF, including inflammatory markers and mortality, were investigated.

Results

In the present study, 14 out of 231 OCSI patients had OCNF. Multivariate analyses of OCSI patients showed that NLR ≥15.3 and LRINEC score ≥6 points were significantly related to OCNF. During the same period, 17 patients had BNF. The OCNF group had significantly higher inflammatory markers than the BNF group when diagnosis, but significantly lower clinical stages at the time and mortality as outcomes.

Conclusion

We found that compared to BNF, OCNF can be detected at lower clinical stage by using indexes, such as NLR and LRINEC score, besides clinical findings, which may help contributing to patient’s relief.

Response to Pembrolizumab After Dose-Reduced Cisplatin Plus Gemcitabine Chemotherapy Is Inferior to That After Carboplatin Plus Gemcitabine Chemotherapy in Cisplatin-Unfit Patients With Advanced Urothelial Carcinoma

INTRODUCTION

Response to pembrolizumab after first-line chemotherapy is vital to prolonged survival in advanced, unresectable, and/or metastatic urothelial carcinoma (aUC). However, there are sparse clinical data on host-tumor immune modification by first-line platinum-based chemotherapy. This study investigated the association between response to first-line gemcitabine plus cisplatin (GC) or carboplatin (GCarbo) chemotherapy and response to subsequent pembrolizumab treatment.

PATIENTS AND METHODS

A multicenter-derived database registered 454 patients diagnosed with aUC between 2008 and 2020. Of these, 108 patients who received first-line GC or GCarbo followed by second-line or later pembrolizumab were eligible for investigation and were classified into 3 groups: 48 receiving full-dose GC, 21 receiving dose-reduced GC, and 39 receiving GCarbo. Overall survival (OS) was calculated using the Kaplan-Meier method and compared using the log-rank test. Possible factors associated with the response to pembrolizumab were evaluated using binary logistic regression methods.

RESULTS

The rate of patients undergoing surgical removal of the primary organ was higher and creatinine clearance was lower in the dose-reduced GC and GCarbo groups than in the full-dose GC groups. Pembrolizumab responders had significantly better survival benefits than nonresponders. The rate of pembrolizumab responders was much higher in first-line chemotherapy responders than in first-line chemotherapy nonresponders. In contrast to the full-dose GC and GCarbo groups, the pembrolizumab responder rate was lower, and no association was observed between response to first-line chemotherapy and response to pembrolizumab in the dose-reduced GC group.

CONCLUSION

Cisplatin and carboplatin may play an important role in the antitumor immune response, which could impact the outcome of subsequent pembrolizumab treatment. Given that the rate of response to pembrolizumab after dose-reduced GC chemotherapy was relatively low, this regimen is not recommended for cis-unfit patients with aUC. Further studies are required to understand the mechanisms responsible for the cross-reactivity of platinum and immune checkpoint inhibitors.

Usefulness of clinical factors for diagnosing and differentiating types of testicular malposition in boys: A retrospective study

OBJECTIVE

To investigate useful objective variables and factors supporting the diagnosis of retractile testis and cryptorchidism by primary care providers, including urologists.

METHODS

This retrospective study included 512 boys diagnosed with retractile testis or cryptorchidism at our institute. Boys with retractile testis were followed up and underwent orchiopexy once the testis became undescended, while boys with cryptorchidism underwent orchiopexy immediately. We investigated trends in the prevalence of testicular malposition and explored useful diagnostic factors for retractile testis and cryptorchidism.

RESULTS

Of 512 boys, 199 were diagnosed with retractile testis and 313 were diagnosed with cryptorchidism. Comparison of clinical information between retractile testis and cryptorchidism showed that age at diagnosis, laterality, and location of the testis were significantly different between the groups (P < 0.0001, P < 0.0001, and P < 0.0001, respectively). The comparison of surgical information also showed that epididymal abnormality and state of processus vaginalis is patency or closure were significantly different between the groups (P = 0.0088 and P = 0.0003, respectively). Multivariate analysis showed that diagnosis at age 0-1 years, unilaterality, and canalicular testis were predictive factors for cryptorchidism (P = 0.001, P < 0.0001, and P < 0.0001, respectively).

CONCLUSIONS

Age at diagnosis, laterality, and location of the testis could be factors to aid the diagnosis of retractile testis and cryptorchidism.

Investigation of OECD 301F ready biodegradability test to evaluate chemical fate in a realistic environment

The OECD 301F ready biodegradability test has been approved for use under the Japanese Chemical Substances Control Law since 2018. This test uses activated sludge obtained from a sewage treatment plant instead of the standard activated sludge used for the 301C test. In addition, the test is allowed to add an inert support or emulsifying agent, and/or to change the volume of the test medium. In this study, we first confirmed that the standard sludge had lower biodegradation activities than the sludge taken from a sewage treatment plant. Second, we showed that biodegradation percentages were increased by adding suitable amounts of silica gel or Tween 80. Third, we found that the biodegradations were accelerated by only increasing the medium volume under the conditions that concentrations of chemical, silica gel, and sludge were held constant. These findings are expected to contribute to the appropriate evaluation of chemical fate in a realistic environment.

Treatment outcomes of adjunctive teriparatide therapy for medication-related osteonecrosis of the jaw (MRONJ): A multicenter retrospective analysis in Japan

BACKGROUND

Therapeutic strategies for patients with medication-related osteonecrosis of the jaw (MRONJ) remain controversial. The aim of the present study was to clarify the effectiveness and safety of teriparatide therapy in Japanese MRONJ patients based on a large number of case series with a multicenter retrospective analysis.

PATIENTS AND METHODS

Between January 2012 and December 2016, 29 patients who were diagnosed with MRONJ at 10 hospitals were treated with teriparatide. The medical records of these patients were retrospectively reviewed to assess the efficacy and safety of teriparatide therapy for MRONJ patients.

RESULTS

Adverse events occurred in 17.2% of patients (5/29). One patient developed severe arthralgia and discontinued teriparatide therapy after 12 days, while others continued the treatment. Among 29 patients, the median period of administration of teriparatide was 14.0 months (range, 0.3-26 months), and treatment outcomes were evaluated as effective in 75.9% of patients with complete resolution in 65.5%. Among patients treated with oral bisphosphonates (BPs), 83.3% were effectively treated with teriparatide and 40% with intravenous BPs. The oral administration of BPs was associated with successful treatment outcomes with teriparatide (p = 0.062).

CONCLUSIONS

Teriparatide therapy has potential as an effective treatment option for MRONJ.

Can CT predict the development of oroantral fistula in patients undergoing maxillary third molar removal?

PURPOSE

In maxillary wisdom tooth extraction, the necessity of CT is unknown. The purpose of this study was to investigate whether CT adding to orthopantomography is useful for predicting oroantral perforation during maxillary third molar extraction.

METHODS

Various risk factors for oroantral perforation during maxillary third molar extraction were investigated by univariate and multivariate analyses. We analyzed those of all patients and the patients who underwent CT, respectively. The proximity of the roots to the maxillary sinus floor (root-sinus [RS] classification) and Archer classification were assessed using panoramic radiography. The number of roots and vertical relationship were assessed using CT.

RESULTS

A total of 604 out of 3299 patients underwent CT adding to orthopantomography. In all cases, multivariate analyses except for CT findings showed that the RS classification type III/IV and the Archer classification Type B/C/D in panoramic findings were significantly correlated with oroantral perforation as radiological findings. In cases for which CT was performed, multivariate analyses showed that one root (OR 12.87) and the vertical relationship Type D (OR 5.63) in CT findings, besides the RS classification type III/IV (OR 4.47) in panoramic findings, were significantly related to oroantral perforation.

CONCLUSION

The RS classification and the Archer classification in panoramic findings can predict the risk of oroantral perforation. The usefulness of CT adding to orthopantomography is limited. However, when the relationship between the upper wisdom tooth and maxillary sinus floor (RS classification) is unclear, to check whether the number of roots is one and the apex of one root is projecting into the maxillary sinus in CT findings, is useful for the prediction.

Uniform straw-like cell architecture for three-dimensional cell-cell communication assay

We fabricated uniform straw-like cell architecture with central lumen using a suture thread within 1 h. The architecture consisting of cancer cells and mature adipocyte was used for cell-cell communication assay, although mature adipocyte could not form spontaneous multi-cellular spheroids. Using the system, it is possible to investigate three-dimensional cell-cell communication as an alternative to animal experiments.

ABBREVIATIONS

EB: embryoid body; 2D: two-dimension; 3D: three-dimension; PBS: phosphate buffered saline.

Generation of the Rat Monoclonal Antibody Against the Extracellular Domain of Human CD63 by DNA Immunization

Human cluster of differentiation 63 (hCD63) is one of the tetraspanin receptors that is abundant on the surface of exosomes. Exosomes are involved in cell-to-cell communication, including from cancer cells to normal cells. It is very important to detect exosomes as a marker for the diagnosis of various diseases. In this study, we report the generation and characterization of a monoclonal antibody (mAb) against the extracellular domain of hCD63 using DNA immunization. This mAb, clone 1C8-2B11, exhibits high performance for use in immunofluorescence and flow cytometry, and it has 10-fold higher affinity than the control antibody that is commercially available. mAb 1C8-2B11 has great potential to be a tool for research and clinical diagnosis.

The effects of short-term calorie restriction on mutations in the spleen cells of infant-irradiated mice

The risk of cancer due to exposure to ionizing radiation is higher in infants than in adults. In a previous study, the effect of adult-onset calorie restriction (CR) on carcinogenesis in mice after early-life exposure to X-rays was examined (Shang, Y, Kakinuma, S, Yamauchi, K, et al. Cancer prevention by adult-onset calorie restriction after infant exposure to ionizing radiation in B6C3F1 male mice. Int J Cancer. 2014; 135: 1038-47). The results showed that the tumor frequency was reduced in the CR group. However, the mechanism of tumor suppression by CR is not yet clear. In this study, we examined the effects of CR on radiation-induced mutations using gpt delta mice, which are useful to analyze mutations in various tissues throughout the whole body. Infant male mice (1-week old) were exposed to 3.8 Gy X-rays and fed a control (95 kcal/week/mouse) or CR (65 kcal/week/mouse) diet from adult stage (7-weeks old). Mice were sacrificed at the age of 7 weeks, 8 weeks and 100 days, and organs (spleen, liver, lung, thymus) were harvested. Mutations at the gpt gene in the DNA from the spleen were analyzed by using a gpt assay protocol that detects primarily point mutations in the gpt gene. The results showed that mutation frequencies were decreased in CR groups compared with non-CR groups. Sequence analysis of the gpt gene in mutants revealed a reduction in the G:C to T:A transversion in CR groups. Since it is known that 8-oxoguanine could result in this base substitution and that CR has an effect of reducing oxidative stress, these results indicate that the suppression of oxidative stress by CR is the cause of the reduction of this transversion.

Improvement of a miRNA inhibitor by intracellular selection

Sequences surrounding the miRNA binding domain of the miRNA inhibitor LidNA were selected intracellularly. The library was transfected into cells, and then, inhibitors that were associated with argonaute 2 were selected. The potent inhibitors were slowly degraded intracellularly, while the lower-activity inhibitors were rapidly degraded. A combination of the selected sequences surrounding the miRNA binding domain enhanced miRNA inhibitory activity.

ABBREVIATIONS

LidNA: DNA that puts a lid on miRNA function; LNA: locked nucleic acid; Ago2: argonaute 2; LNA: locked nucleic acid.

Structural improvement of LidNA: delta-type LidNA is a potent miRNA inhibitor constructed with unmodified DNA

Many miRNA inhibitors have been developed, including chemically modified oligonucleotides, such as 2'-O-methylated RNA and locked nucleic acid (LNA). Unmodified DNA has not yet been reported as a miRNA inhibitor due to relatively low DNA/miRNA binding affinity. We designed a structured DNA, LidNA, which was constructed with unmodified DNA, consisting of a complementary sequence to the target miRNA flanked by two structured DNA regions, such as double-stranded DNA. LidNA inhibited miRNA activity more potently than 2'-O-methylated RNA or LNA. To optimize LidNA, two double-stranded regions were joined, causing the molecule to assume a delta-like shape, which we termed delta-type LidNA. Delta-type LidNAs were developed to target endogenous and exogenous miRNAs, and exhibited potent miRNA inhibitory effects with a duration of at least 10 days. Delta-type LidNA-21, which targeted miR-21, inhibited the growth of cancer cell lines. This newly developed LidNA could contribute to miRNA studies across multiple fields.Abbreviations: LidNA: DNA that puts a lid on miRNA function; LNA: locked nucleic acid; 3'-UTR: 3'-untranslated regions; RISC: RNA-induced silencing complex; MBL: Molecular beacon-like LidNA; YMBL: Y-type molecular beacon-like LidNA; TDMD: target-directed microRNA degradation.

Improved cancer inhibition by miR-143 with a longer passenger strand than natural miR-143

We improved miR-143, which inhibits the growth of cancer cells, by the replacement of the passenger strand. As a result, new miR-143 variants were developed with a single mismatch at the 4th position from the 3'-terminal of the guide strand and an RNA passenger strand with a G-rich flanking DNA region. A reporter gene assay showed that the 80% inhibitory concentration of the new miR-143, long miR-143, was 69 pM, which was three times lower than that of natural miR-143. Long miR-143 inhibited the growth of two cancer cell lines, HeLa-S3 and MIAPaCa-2, more effectively than natural miR-143. This method could be applied to other miRNA families and should be useful for the development of miRNA drugs.

Uniform spheroid formation on a laboratory-made, low cell attachment surface consisting of a chitin sheet

We utilized the reaction of chitosan with acetic anhydride to form a chitin gel. This gel was then dried, which formed a chitin sheet. The procedure was extremely easy for a biologist unfamiliar with materials engineering. Spheroids derived from HEK293T cells were formed on the chitin sheet, because the spheroids slightly attached and slowly moved on the chitin sheet.

Fluorescein isothiocyanate and blue light irradiation alter cell-adhesiveness of cross-linked albumin films for cell patterning

Cross-linked albumin films, which are non-cell adhesive, were altered to be cell-adhesive by the combination of varied concentrations of fluorescein isothiocyanate and blue light irradiation. In this system, cell patterning was developed with two different cell lines by sequential seeding.Abbreviations: BSA: bovine serum albumin; EGDE: ethylene glycol diglycidyl ether; PBS: Dulbecco's phosphate buffered saline.

Chitin degradation enzyme-responsive system for controlled release of fibroblast growth factor-2

Chitin is widely found in fungal cell walls and arthropod exoskeletons, and is used as a biomedical material. However, chitin is not water-soluble, restricting its use for controlled release materials. We found that water-soluble chitosan can be acetylated to produce a chitin equivalent, or chitin gel. Chitin gel, produced by mixing chitosan solution with acetic anhydride, can be degraded by lysozyme and fetal bovine serum, so could provide an ideal means for controlled release in biological systems. We tested a combination of chitin gel with a chitin binding domain (CBD) fusion protein as a controlled release system regulated by chitin degradation. A fusion protein consisting of fibroblast growth factor 2 (FGF-2) fused to CBD bound the chitin gel, and was released time-dependently rather than as an initial burst during lysozyme degradation, suggesting that this system could provide a means for controlled drug release in biological systems. Contrastingly, the trinitrophenyl residue (TNP-X) covalently bound to chitin gel, and was released by lysozyme degradation with an initial burst. If release of CBD-FGF-2 were simply dependent on lysozyme degradation of the chitin gel, the release behavior of CBD-FGF-2 would be similar to that of TNP-X, with an initial burst. Therefore, we propose that CBD-FGF-2 repeats the cycle of binding, release, and re-binding to the chitin gel during degradation. This system allows for a time-dependent, controlled release of CBD-FGF-2 without an initial burst.

Induction of somatic mutations by low-dose X-rays: the challenge in recognizing radiation-induced events

It is difficult to distinguish radiation-induced events from spontaneous events during induction of stochastic effects, especially in the case of low-dose or low-dose-rate exposures. By using a hypersensitive system for detecting somatic mutations at the HPRT1 locus, we investigated the frequency and spectrum of mutations induced by low-dose X-rays. The mutant frequencies induced by doses of >0.15 Gy were statistically significant when compared with the spontaneous frequency, and a clear dose dependency was also observed for mutant frequencies at doses of >0.15 Gy. In contrast, mutant frequencies at doses of <0.1 Gy occurred at non-significant levels. The mutation spectrum in HPRT-deficient mutants revealed that the type of mutations induced by low-dose exposures was similar to that seen in spontaneous mutants. An apparent change in mutation type was observed for mutants induced by doses of >0.2 Gy. Our observations suggest that there could be a critical dose for mutation induction at between 0.1 Gy and 0.2 Gy, where mutagenic events are induced by multiple DNA double-strand breaks (DSBs). These observations also suggest that low-dose radiation delivered at doses of <0.1 Gy may not result in DSB-induced mutations but may enhance spontaneous mutagenesis events.

Abstract P6-15-05: Randomized controlled trial of neoadjuvant eribulin mesylate versus paclitaxel in women with operable breast cancer (JONIE-3 study)

Background:

Although treatment of eribulin mesylate (E) improved overall survival in metastatic breast cancer (BC) patients, little is known about the efficacy in early BC. The hypothesis of this study is that sequential administration of E followed by FEC would have less toxic, particularly peripheral neuropathy, and also have similar effect compared to paclitaxel (P) followed by FEC as primary systemic therapy (PST) for woman with operable BC.

Methods:

This is a phase II multicenter open label study (UMIN000012817). Patients (pts) were randomly assigned to either E (1.4mg/m2, d1 and d8, q21 days, 4 cycles) + FEC (fluorouracil 500 mg/m2, epirubicin 100 mg/m2, and cyclophosphamide 500 mg/m2) or P (80mg/m2, weekly, 12 cycles) + FEC as PST. HER2+ patients were allowed to receive trastuzumab. Stratification factors were ER, HER2, and menopausal status. Primary endpoint was the incidence of peripheral sensory and motor neuropathy (PSN and PMN) with Grade 1 or higher according to CTCAE ver.4.0. Secondary endpoints were pathological complete response (pCR) rates (ypT0/is/ypN0), clinical response rates (CR+PR), and adverse events. Safety was assessed in all pts who received at least one dose of the study drug.

Results:

Between 12/2013 to 3/2016, 121 pts were randomly assigned equally to E + FEC and P + FEC. Excluding 5 pts from the primary assessment, 116 pts (58 in each group) were included in the full analysis set. The characteristics of the pts were similar in the two arms. At the end of E or P administration, the incidences of PSN were 55.4% and 92.9% in E and P arm, respectively (p&lt;0.001). The incidences of PMN were 25.9% and 44.9% in E and P arm, respectively (p=0.049). At the end of E or P + FEC, PSN accounts for 38.9% in E arm and 85.2% in P arm (p&lt;0.001), and PMN accounts for 20.7% in E arm and 32.8% in P arm (p=0.201). The pCR rates in E and P arm were 20.7% and 29.8% (p=0.092). The clinical response rates in E and P arm were 82.2% and 91.0% (p=0.108). No statistical significant difference was found in efficacy of PST between E and P.

Conclusion:

This randomized phase II study revealed that eribulin had favorable peripheral neuropathy profile with modest efficacy in the neoadjuvant setting, compared with paclitaxel.

Citation Format: Miura D, Hasegawa Y, Ishikawa T, Tachibana A, Horiguchi J, Hayashi M, Miyashita M, Kubota T, Narui K, Suzuki M, Akazawa K, Kohno N. Randomized controlled trial of neoadjuvant eribulin mesylate versus paclitaxel in women with operable breast cancer (JONIE-3 study) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-15-05.

Tissue-specific and time-dependent clonal expansion of ENU-induced mutant cells in gpt delta mice

DNA mutations play a crucial role in the origins of cancer, and the clonal expansion of mutant cells is one of the fundamental steps in multistage carcinogenesis. In this study, we correlated tumor incidence in B6C3F1 mice during the period after exposure to N-ethyl-N-nitrosourea (ENU) with the persistence of ENU-induced mutant clones in transgenic gpt delta B6C3F1 mice. The induced gpt mutations afforded no selective advantage in the mouse cells and could be distinguished by a mutational spectrum that is characteristic of ENU treatment. The gpt mutations were passengers of the mutant cell of origin and its daughter cells and thus could be used as neutral markers of clones that arose and persisted in the tissues. Female B6C3F1 mice exposed for 1 month to 200 ppm ENU in the drinking water developed early thymic lymphomas and late liver and lung tumors. To assay gpt mutations, we sampled the thymus, liver, lung, and small intestine of female gpt delta mice at 3 days, 4 weeks, and 8 weeks after the end of ENU exposure. Our results reveal that, in all four tissues, the ENU-induced gpt mutations persisted for weeks after the end of mutagen exposure. Clonal expansion of mutant cells was observed in the thymus and small intestine, with the thymus showing larger clone sizes. These results indicate that the clearance of mutant cells and the potential for clonal expansion during normal tissue growth depends on tissue type and that these factors may affect the sensitivity of different tissues to carcinogenesis. Environ. Mol. Mutagen. 58:592-606, 2017. © 2017 Wiley Periodicals, Inc.

The risk factors associated with postoperative hemorrhage after tooth extraction: a multi-center retrospective study of patients receiving oral antithrombotic therapy

The purpose of this study was to retrospectively investigate the multivariate relationships between specific risk factors and postoperative hemorrhage after tooth extraction in patients who were prescribed oral antithrombotic therapy. Risk factors for postoperative hemorrhage after tooth extraction were evaluated using univariate and multivariate analyses. Patient characteristics such as age and gender; the presence or absence of known comorbidities such as diabetes mellitus, hypertension, cerebral infarction, and alcohol consumption; and perioperative diarrhea were assessed. The drug used for antithrombotic therapy, preoperative blood test results, the presence or absence of preoperative antibiotics or nonsteroidal anti-inflammatory drug (NSAID) administration, the total number of extracted teeth, and the type of surgical procedures were also evaluated. We found that the preoperative administration of antibiotics (odds ratio (OR) = 2.52), an increased prothrombin time international normalized ratio (PT-INR) value (OR = 1.94), and the extraction of multiple teeth (OR = 2.10) were significantly associated with postoperative hemorrhage. There was no significant association between postoperative hemorrhage and any other demographic factors or comorbidities, including concomitant alcohol use. We demonstrated the multivariate relationship between the risk factors and postoperative hemorrhage after tooth extraction in patients receiving oral antithrombotic therapy. Surgeons should be aware of these risks and monitor the PT-INR of anticoagulated patients.

A multicenter retrospective study of the risk factors associated with medication-related osteonecrosis of the jaw after tooth extraction in patients receiving oral bisphosphonate therapy: can primary wound closure and a drug holiday really prevent MRONJ?

Root amputation, extraction of a single tooth, bone loss or severe tooth mobility, and an unclosed wound were significantly associated with increased risk of developing medication-related osteonecrosis of the jaw (MRONJ). We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates.

INTRODUCTION

Osteonecrosis of the jaws can occur following tooth extraction in patients receiving bisphosphonate drugs. Various strategies for minimizing the risk of MRONJ have been advanced, but no studies have comprehensively analyzed the efficacy of factors such as primary wound closure, demographics, and drug holidays in reducing its incidence. The purpose of this study was to retrospectively investigate the relationships between these various risk factors after tooth extraction in patients receiving oral bisphosphonate therapy.

METHODS

Risk factors for MRONJ after tooth extraction were evaluated using univariate and multivariate analysis. All patients were investigated with regard to demographics; type and duration of oral bisphosphonate use; whether they underwent a discontinuation of oral bisphosphonates before tooth extraction (drug holiday), and the duration of such discontinuation; and whether any additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed.

RESULTS

We found that root amputation (OR = 6.64), extraction of a single tooth (OR = 3.70), bone loss or severe tooth mobility (OR = 3.60), and an unclosed wound (OR = 2.51) were significantly associated with increased risk of developing MRONJ.

CONCLUSIONS

We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates. We find no evidence supporting the efficacy of a pre-extraction short-term drug holiday from oral bisphosphonates in reducing the risk of MRONJ.

Risk factors associated with oroantral perforation during surgical removal of maxillary third molar teeth

PURPOSE

The relationship between radiographic findings and the occurrence of oroantral perforation is controversial. Few studies have quantitatively analyzed the risk factors contributing to oroantral perforation, and no study has reported multivariate analysis of the relationship(s) between these various factors. This retrospective study aims to fill this void.

METHODS

Various risk factors for oroantral perforation during maxillary third molar extraction were investigated by univariate and multivariate analysis. The proximity of the roots to the maxillary sinus floor (root-sinus [RS] classification) was assessed using panoramic radiography and classified as types 1-5. The relationship between the maxillary second and third molars was classified according to a modified version of the Archer classification. The relative depth of the maxillary third molar in the bone was classified as class A-C, and its angulation relative to the long axis of the second molar was also recorded.

RESULTS

Performance of an incision (OR 5.16), mesioangular tooth angulation (OR 6.05), and type 3 RS classification (i.e., significant superimposition of the roots of all posterior maxillary teeth with the sinus floor; OR 10.18) were all identified as risk factors with significant association to an outcome of oroantral perforation.

CONCLUSION

To our knowledge, this is the first multivariate analysis of the risk factors for oroantral perforation during surgical extraction of the maxillary third molar. This RS classification may offer a new predictive parameter for estimating the risk of oroantral perforation.

A multi-centre retrospective study of mandibular fractures: do occlusal support and the mandibular third molar affect mandibular angle and condylar fractures?

This retrospective study was performed to investigate the influence of occlusal support and the presence, state, and position of mandibular third molars on the incidence of mandibular angle and condylar fractures. The following variables were investigated: age, sex, cause of fracture, presence and state (impaction, angulation, and the number of roots) of the mandibular third molars, site of the mandibular fracture, presence of occlusal support, duration of intermaxillary fixation, and postoperative complications. Various risk factors for mandibular angle and condylar fractures were investigated by univariate analysis. The risk of mandibular angle fracture was significantly higher in patients with occlusal support and mandibular third molars. The risk of condylar fracture was significantly higher in patients without occlusal support or mandibular third molars. The position and angulation of the mandibular third molars were not significant risk factors in mandibular angle and condylar fractures. This study demonstrated the influence of occlusal support and the presence of mandibular third molars on the incidence of mandibular angle and condylar fractures. The presence of occlusal support may be a more important factor affecting mandibular angle or condylar fractures than the position of the mandibular third molars.

Changes in Cell Adhesiveness and Physicochemical Properties of Cross-Linked Albumin Films after Ultraviolet Irradiation

We discovered the unique cell adhesive properties of ultraviolet (UV)-irradiated albumin films. Albumin films prepared using a cross-linking reagent with epoxy groups maintained native albumin properties, such as resistance to cell adhesion. Interestingly, the cell adhesive properties of films varied depending upon the UV irradiation time; specifically, cell adhesiveness increased until 2 h of UV irradiation, when the cell number attached to the film was similar to that of culture dishes, and then cell adhesiveness decreased until 20 h of UV irradiation, after which the surface returned to the initial non-adhesive state. To elucidate the molecular mechanisms underlying this phenomenon, we examined the effect of UV irradiation on albumin film properties. The following changes occurred in response to UV irradiation: decreased α-helical structure, cleavage of albumin peptide bonds, and increased hydrophilicity and oxygen content of the albumin film surface. In addition, we found a positive correlation between the degree of cell adhesion and the amount of fibronectin adsorbed on the film. Taken together, UV-induced changes in films highly affect the amount of cell adhesion proteins adsorbed on the films depending upon the irradiation time, which determines cell adhesion behavior.

The effect of age at exposure on the inactivating mechanisms and relative contributions of key tumor suppressor genes in radiation-induced mouse T-cell lymphomas

Children are considered more sensitive to radiation-induced cancer than adults, yet any differences in genomic alterations associated with age-at-exposure and their underlying mechanisms remain unclear. We assessed genome-wide DNA copy number and mutation of key tumor suppressor genes in T-cell lymphomas arising after weekly irradiation of female B6C3F1 mice with 1.2Gy X-rays for 4 consecutive weeks starting during infancy (1 week old), adolescence (4 weeks old) or as young adults (8 weeks old). Although T-cell lymphoma incidence was similar, loss of heterozygosity at Cdkn2a on chromosome 4 and at Ikaros on chromosome 11 was more frequent in the two older groups, while loss at the Pten locus on chromosome 19 was more frequent in the infant-irradiated group. Cdkn2a and Ikaros mutation/loss was a common feature of the young adult-irradiation group, with Ikaros frequently (50%) incurring multiple independent hits (including deletions and mutations) or suffering a single hit predicted to result in a dominant negative protein (such as those lacking exon 4, an isoform we have designated Ik12, which lacks two DNA binding zinc-finger domains). Conversely, Pten mutations were more frequent after early irradiation (60%) than after young adult-irradiation (30%). Homozygous Pten mutations occurred without DNA copy number change after irradiation starting in infancy, suggesting duplication of the mutated allele by chromosome mis-segregation or mitotic recombination. Our findings demonstrate that while deletions on chromosomes 4 and 11 affecting Cdkn2a and Ikaros are a prominent feature of young adult irradiation-induced T-cell lymphoma, tumors arising after irradiation from infancy suffer a second hit in Pten by mis-segregation or recombination. This is the first report showing an influence of age-at-exposure on genomic alterations of tumor suppressor genes and their relative involvement in radiation-induced T-cell lymphoma. These data are important for considering the risks associated with childhood exposure to radiation.