The extremely low frequency-electromagnetic field (ELF-EMF) refers to the frequency range of 0-300 Hz. It has been reported that it causes biological effects on cell survival, growth, and function. Structural changes were observed in the cell membranes of bacteria exposed to a certain intensity of ELF-EMF, indicating that exposure of bacteria to ELF-EMF can directly affect the cell membrane and affect the survival and growth of bacteria. The purpose of this study was to investigate the effect of the application of low frequency square wave positive voltages on Aggregatibactor actinomycetemcomitans (A. actinomycetemcomitans), a putative pathogen of periodontal disease. A square wave positive voltage output of 20 V or less at low frequency (0-300 Hz) was applied to A. actinomycetemcomitans in a range of 60 minutes. Changes in the population of bacteria were observed by absorbance measurement, colony forming unit (CFU/ml) evaluation, and high-resolution field-emission scanning electron microscopy (HR FE-SEM). The results show that the most effective offset and frequency in inhibiting bacterial growth are 0.7V and 7.83 Hz (Schumann resonance). As the applied time increased and the voltage increased, it was effective in inhibiting bacterial growth. These results led to the conclusion that bacterial growth can be inhibited even at low frequencies below 10 Hz, and it was experimentally proven that the frequency, voltage setting, and exposure time of ELF-EMF have a significant effect on reducing the growth of A. actinomycetemcomitans.

Purpose: We aimed to investigate the risk factors and patterns of locoregional recurrence (LRR) after radical nephrectomy (RN) in patients with locally advanced renal cell carcinoma (RCC). Materials and Methods: We retrospectively analyzed 245 patients who underwent RN for non-metastatic pT3-4 RCC from January 2006 to January 2016. We analyzed the risk factors associated with poor locoregional control using Cox regression. Anatomical mapping was performed on reference computed tomography scans showing intact kidneys. Results: The median follow-up duration was 56 months (range, 1 to 128 months). Tumor extension to renal vessels or the inferior vena cava (IVC) and Fuhrman’s nuclear grade IV were identified as independent risk factors of LRR. The 5-year actuarial LRR rates in groups with no risk factor, one risk factor, and two risk factors were 2.3%, 19.8%, and 30.8%, respectively (p < 0.001). The locations of LRR were distributed as follows: aortocaval area (n=2), paraaortic area (n=4), retrocaval area (n=5), and tumor bed (n=11). No LRR was observed above the celiac axis (CA) or under the inferior mesenteric artery (IMA). Conclusion Tumor extension to renal vessels or the IVC and Fuhrman’s nuclear grade IV were the independent risk factors associated with LRR after RN for pT3-4 RCC. The locations of LRR after RN for RCC were distributed in the tumor bed and regional lymphatic area from the bifurcation of the CA to that of the IMA.

Background: We aimed to investigate the effect of epidural polydeoxyribonucleotide (PDRN) on mechanical allodynia and motor dysfunction in a rat model of lumbar foraminal stenosis (LFS). Methods: This study was conducted in two stages, using male Sprague-Dawley rats. The rats were randomly divided into eight groups. In the first stage, the groups were as follows: vehicle (V), sham (S), and epidural PDRN at 5 (P5), 8 (P8), and 10 (P10) mg/kg; and in the second stage, they were as follows: intraperitoneal PDRN 8 mg/kg, epidural 3,7-dimethyl-1-propargilxanthine (DMPX) (0.1 mg/kg), and DMPX (0.1 mg/kg). The LFS model was established, except for the S group. After an epidural injection of the test solutions, von Frey and treadmill tests were conducted for 3 weeks. Subsequently, histopathologic examinations were conducted in the V, S, P5, and P10 groups. Results: A total of 65 rats were included. The P8 and P10 groups showed significant recovery from mechanical allodynia and motor dysfunction at all time points after drug administration compared to the V group. These effects were abolished by concomitant administration of DMPX. On histopathological examination, no epineurial inflammation or fibrosis was observed in the epidural PDRN groups. Conclusions Epidural injection of PDRN significantly improves mechanical allodynia and motor dysfunction in a rat model of LFS, which is mediated by the spinal adenosine A2A receptor. The present data support the need for further research to determine the role of epidural PDRN in spinal stenosis treatment.

Background: We aimed to investigate the effect of epidural polydeoxyribonucleotide (PDRN) on mechanical allodynia and motor dysfunction in a rat model of lumbar foraminal stenosis (LFS). Methods: This study was conducted in two stages, using male Sprague-Dawley rats. The rats were randomly divided into eight groups. In the first stage, the groups were as follows: vehicle (V), sham (S), and epidural PDRN at 5 (P5), 8 (P8), and 10 (P10) mg/kg; and in the second stage, they were as follows: intraperitoneal PDRN 8 mg/kg, epidural 3,7-dimethyl-1-propargilxanthine (DMPX) (0.1 mg/kg), and DMPX (0.1 mg/kg). The LFS model was established, except for the S group. After an epidural injection of the test solutions, von Frey and treadmill tests were conducted for 3 weeks. Subsequently, histopathologic examinations were conducted in the V, S, P5, and P10 groups. Results: A total of 65 rats were included. The P8 and P10 groups showed significant recovery from mechanical allodynia and motor dysfunction at all time points after drug administration compared to the V group. These effects were abolished by concomitant administration of DMPX. On histopathological examination, no epineurial inflammation or fibrosis was observed in the epidural PDRN groups. Conclusions Epidural injection of PDRN significantly improves mechanical allodynia and motor dysfunction in a rat model of LFS, which is mediated by the spinal adenosine A2A receptor. The present data support the need for further research to determine the role of epidural PDRN in spinal stenosis treatment.

Background: We recently discovered the presence of specialized nail mesenchyme below the nail matrix and designated it as onychomatricodermis. Objective: We did further research to characterize the histologic, histochemical, immunohistochemical and ultrastructural features of the onychomatricodermis containing onychofibroblasts in the nail unit. Methods: Ten polydactyly nail unit specimens and 8 nail matrix biopsies were included. H&E-stained slides were reviewed. We did Alcian blue staining and Masson Trichrome staining, as well as immunohistochemical staining for type Ⅰ collagen, CD10, CD13 and CD34. In addition, polydactyly nail units were examined by transmission electron microscopy. Results: In H&E staining, the specialized mesenchyme called onychomatricodermis was observed to be slightly distant from the undersurface of the nail matrix and be less eosinophilic area. Onychomatricodermal onychofibroblasts showed light purple abundant cytoplasm.Masson Trichrome staining revealed fewer collagen fibers within the onychomatricodermis. In Alcian blue staining the onychomatricodermis showed mucin deposition within the onychofibroblasts and around them. Immunohistochemically, type Ⅰ collagen was expressed much less in the onychomatricodermis while it was strongly expressed elsewhere in the nail unit. In nail matrix biopsy specimens onychomatricodermal onychofibroblasts expressed CD10 and CD13 strongly, and expressed CD34 as well. Ultrastructurally, collagen fibrils were found sparsely within the onychomatricodermis, whereas collagen fibrils were densely distributed in the dermis of other parts of the nail unit. Conclusion We demonstrated that there was less collagen expression in the onychomatricodermis containing onychofibroblasts. In addition, we found morphological and immunohistochemical features of onychomatricodermal onychofibroblasts (onychofibroblasts of Dongyoun). These findings support the presence of onychomatricodermis containing onychofibroblasts in the nail unit.

Purpose: There remains a lot of unmet need to increase understanding of node-positive (ypN+) muscle invasive bladder cancer (MIBC) after neoadjuvant chemotherapy and radical cystectomy to decide the appropriate therapeutics. Materials and Methods: In a retrospective study using the center cancer chemotherapy registry, we found 113 MIBC patients who were treated with neoadjuvant chemotherapy involving gemcitabine and cisplatin (GP) followed by radical cystectomy between 2010 and 2014. Disease-free survival (DFS) and overall survival (OS) were compared according to the pathologic node positivity (ypN- vs. ypN+). Among a total of 165 patients with MIBC who received neoadjuvant chemotherapy involving GP, 118 underwent radical cystectomy. In 46 patients with ypN+ disease, DFS and OS were evaluated according to administration of adjuvant GP. Results: After neoadjuvant chemotherapy and radical cystectomy, 41% of patients had ypN+ disease, which showed significantly shorter DFS (median, 7.4 months; 95% confidence interval [CI], 5.3–9.6 months) and OS (median, 20.0 months; 95% CI, 13.4–26.6 months) compared to those with ypN- disease. The patients with ypN+ disease had a high risk of recurrence or death, regardless of the administration of adjuvant chemotherapy or adjuvant regimen. Conclusions Within the limitations of this retrospective study, MIBC patients with ypN+ disease despite neoadjuvant chemotherapy and radical cystectomy had a poor prognosis. Further studies involving novel, effective adjuvant treatment including immunotherapy agents are needed to reduce the high risk of recurrence or death in these patients.

Purpose: There remains a lot of unmet need to increase understanding of node-positive (ypN+) muscle invasive bladder cancer (MIBC) after neoadjuvant chemotherapy and radical cystectomy to decide the appropriate therapeutics. Materials and Methods: In a retrospective study using the center cancer chemotherapy registry, we found 113 MIBC patients who were treated with neoadjuvant chemotherapy involving gemcitabine and cisplatin (GP) followed by radical cystectomy between 2010 and 2014. Disease-free survival (DFS) and overall survival (OS) were compared according to the pathologic node positivity (ypN- vs. ypN+). Among a total of 165 patients with MIBC who received neoadjuvant chemotherapy involving GP, 118 underwent radical cystectomy. In 46 patients with ypN+ disease, DFS and OS were evaluated according to administration of adjuvant GP. Results: After neoadjuvant chemotherapy and radical cystectomy, 41% of patients had ypN+ disease, which showed significantly shorter DFS (median, 7.4 months; 95% confidence interval [CI], 5.3–9.6 months) and OS (median, 20.0 months; 95% CI, 13.4–26.6 months) compared to those with ypN- disease. The patients with ypN+ disease had a high risk of recurrence or death, regardless of the administration of adjuvant chemotherapy or adjuvant regimen. Conclusions Within the limitations of this retrospective study, MIBC patients with ypN+ disease despite neoadjuvant chemotherapy and radical cystectomy had a poor prognosis. Further studies involving novel, effective adjuvant treatment including immunotherapy agents are needed to reduce the high risk of recurrence or death in these patients.

Background: Non-HLA antibodies, anti-angiotensin II type 1 receptor antibodies (anti-AT1R) and anti-endothelial cell antibodies (AECA), are known to play a role in allograft rejection. We evaluated the role of both antibodies in predicting post-transplant outcomes in low-risk living donor kidney transplantation (LDKT) recipients. Methods: In 94 consecutive LDKT recipients who were ABO compatible and negative for pre-transplant HLA donor-specific antibodies, we determined the levels of anti-AT1Rs using an enzyme-linked immunosorbent assay and the presence of AECAs using a flow cytometric endothelial cell crossmatch (ECXM) assay with pre-transplant sera. Hazard ratio (HR) was calculated to predict post-transplant outcomes. Results: Pre-transplant anti-AT1Rs (≥11.5 U/mL) and AECAs were observed in 36 (38.3%) and 22 recipients (23.4%), respectively; 11 recipients had both. Pre-transplant anti-AT1Rs were a significant risk factor for the development of acute rejection (AR) (HR 2.09; P=0.018), while a positive AECA status was associated with AR or microvascular inflammation only (HR 2.47; P=0.004) throughout the follow-up period. In particular, AECA (+) recipients with ≥11.5 U/mL anti-AT1Rs exhibited a significant effect on creatinine and estimated glomerular filtration rate (P<0.001; P=0.028), although the risk of AR was not significant. Conclusions Pre-transplant anti-AT1Rs and AECAs have independent negative effects on post-transplant outcomes in low-risk LDKT recipients. Assessment of both antibodies would be helpful in stratifying the pre-transplant immunological risk, even in low-risk LDKT recipients.

PURPOSE: The efficacy of nivolumab in metastatic renal cell carcinoma (mRCC) has been proven. However, the nivolumab experience in Korean patients with mRCC is still poorly reported. We report initial experiences with the efficacy and safety of nivolumab in patients with mRCC. MATERIALS AND METHODS: We retrospectively reviewed records for 25 patients with mRCC who had failed targeted therapy and were treated by nivolumab (2 mg/kg, every 2 weeks) at a single institution. The primary endpoint was objective response rate (ORR), and secondary endpoints were progression-free survival (PFS), safety profiles, and ORR in a programmed cell death receptor ligand 1 (PD-L1) expression subgroup. RESULTS: The median age was 60 years and 16 patients (64%) were male. Objective responses were achieved in 8 patients (32.0%) (complete response, 1; partial response, 7). Median PFS was 3.0 months (95% confidence interval, 1.46–4.53). Treatment-related adverse events (AEs) of any grade were observed in 19 patients (76.0%) with 6 (24.0%) experiencing grade 3 to 4 treatment-related AEs. In subgroups by PD-L1 expression levels classified as 1% or greater and less than 1%, ORR was 50% and 0%, respectively. CONCLUSIONS: This study showed the efficacy and safety of initial experiences with nivolumab in Korean patients with mRCC who had failed targeted therapy. Our results were comparable to recent clinical trials on nivolumab in mRCC.
Antigens, CD274 ; Carcinoma, Renal Cell ; Cell Death ; Disease-Free Survival ; Humans ; Male ; Neoplasm Metastasis ; Retrospective Studies ; Treatment Outcome

PURPOSE: Treatment targeting immune checkpoint with programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors has demonstrated efficacy and tolerability in the treatment of metastatic urothelial carcinoma (mUC). We investigated the efficacy and safety of atezolizumab in mUC patients who failed platinum-based chemotherapy. MATERIALS AND METHODS: A retrospective study using the Samsung Medical Center cancer chemotherapy registry was performed on 50 consecutive patients with mUC treated with atezolizumab, regardless of their PD-L1(SP142) status, as salvage therapy after chemotherapy failure between May 2017 and June 2018. Endpoints included overall response rate (RR), progression-free survival (PFS), and safety. RESULTS: Among 50 patients, men constituted 76% and the median age was 68 years (range, 46 to 82 years). Twenty-three patients (46%) received atezolizumab as second-line therapy. PD-L1 (SP142) status IC0/1 and IC2/3 were found in 21 (42%) and 21 (42%) of patients, respectively; in eight patients (16%), PD-L1 (SP142) expression was not available. Atezolizumab was generally well tolerated, with pruritus and fatigue being the most commonly observed toxicities. As a result, partial response was noted in 20 patients (40%), with 12 (24%) stable diseases. RRwas higherin IC2/3 (62%) than in IC0/1 patients (24%, p=0.013). The median PFS was 7.4 months (95% confidence interval, 3.4 to 11.4 months). As expected, PFS also was significantly longer in IC2/3 patients than in IC0/1 (median, 12.7 vs. 2.1 months; p=0.005). PFS was not significantly influenced by age, sex, performance status, number of previous chemotherapy, site of metastases, or any of the baseline laboratory parameters. CONCLUSION: In this retrospective study, atezolizumab demonstrated clinically efficacy and tolerability in unselected mUC patients who failed platinum-based chemotherapy.
Disease-Free Survival ; Drug Therapy ; Fatigue ; Humans ; Male ; Neoplasm Metastasis ; Pruritus ; Retrospective Studies ; Salvage Therapy