Early Assessment of Radiation Treatment at Clinical Field Strength by D2O Administration and Deuterium MRI

PURPOSE/OBJECTIVE(S)

An accurate and non-invasive assessment of tumor response following treatment is essential. Traditional anatomical imaging techniques are insufficient before a significant morphological change can be observed. Metabolic imaging of molecular processes in the living body is also used. In recent years, deuterium magnetic resonance spectroscopic (MRS) imaging has been demonstrated as an alternative for cancer metabolic imaging by high-field (4-11T) MRI using deuterium-labeled molecules as a contrast agent. The study aim was to evaluate the feasibility of using deuterium MRI 1.5T for tumor visualization and early assessment of the efficacy of three anticancer treatment strategies (radiation and anticancer drugs) in pancreatic cancer model mice given heavy water (D2O) to induce deuterium (2H)-tissue labeling.

MATERIALS/METHODS

A MIA PaCa-2 pancreatic cancer model of six BALB/c-nu mice was prepared, and repeated deuterium MRI was performed during the first 10 days after starting free drinking of 30% D2O. We also evaluated 2H accumulation in the tumor after irradiation, bevacizumab administration, or gemcitabine administration of other 20 mice. Additional confirmatory proton MRI, ex vivo metabolic hyperpolarization 13C-MRS and histopathology were performed.

RESULTS

The mouse's whole-body distribution of 2H was visible 1 day after drinking, and the signal intensity increased daily. Although the tumor size did not change 1 and 3 days after irradiation, the amount of 2H in the tumor decreased significantly. The 2H image intensity of the tumor also significantly decreased after the administration of bevacizumab or gemcitabine. Metabolic hyperpolarization 13C-MRS, proton MRI and 2H-NMR spectroscopy confirmed the efficacy of the anticancer treatments.

CONCLUSION

Deuterium MRI at 1.5T proved feasibility to track 2H distribution throughout mouse tissues during D2O administration and revealed a higher 2H accumulation in the tumor xenografts. This research demonstrated a promising successful method for early assessment of radiotherapy and chemotherapy of pancreatic cancer.

The New Quantum Image by Dynamic Nuclear Polarized MRI for the Assessment of Cardiac Radioablation to the Cavotricuspid Isthmus

PURPOSE/OBJECTIVE(S)

Cardiac arrhythmias are usually treated with invasive, time consuming catheter ablation techniques. While recently stereotactic body radiotherapy (SBRT) is an emerging non-invasive treatment in the management of cardiac arrhythmias. To identify and assess the cardiac radioablation by MR examination, including diffusion-weighted MRI, dynamic Gd-enhanced MRI, MR spectroscopy, and T2-weighted MRI early after SBRT is very difficult. We have been developing the free radical imaging methods using Dynamic Nuclear Polarization (DNP)-MRI with nitroxyl radicals as a redox probe (e.g., 4-Methacryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempo methacrylate; TempoMC)). In this study, we examined the possibility of in vivo spatiotemporal visualization of SBRT for cardiac radioablation to the cavotricuspid isthmus (CTI) based on redox reaction by in vivo DNP-MRI.

MATERIALS/METHODS

All animal procedures were approved by institutional animal care and use committee and performed in full compliance with its guidelines. This study was conducted with two approaches. First, four mini pigs underwent electrophysiology assessment using electroanatomic mapping (EAM) before and 3 months after SBRT with single-fraction doses of 25 Gy. The target of CTI was defined by cardiologist. We defined the planning target volume (PTV): the internal margin (IM) + set up margin (SM) = SI 15 mm, AP 10mm, LR 10 mm were added to the target. Radiotherapy plans were created by the software used in daily clinical practice. Second, free radical imaging by low filed type of DNP-MRI was performed on the four mice before and after 25 Gy and 10 Gy irradiation to whole heart. ESR signal measurements were also performed.

RESULTS

A total dose of 25 Gy was successfully delivered to PTV in a single procedure in all mini pigs. EAM visualized the irradiated site and confirmed clockwise conduction block across the CTI. Although routine MRI could not detect the cardiac radiation injury clearly, the four mice of heart were well delineated on MRI and clearly visualized by DNP-MRI. DNP-MRI signal of TempoMC were decreased depending on prescribed irradiation dose.

CONCLUSION

These data demonstrated the safety and feasibility of SBRT for creating conduction block across the CTI in mini pigs. Although to identify and assess the irradiated site by routine MR examination was impossible, the free radical imaging methods using Dynamic Nuclear Polarization (DNP)-MRI with TempoMC could be a promising successful method for the assessment of cardiac radioablation. This new quantum image by DNP-MRI will open the possibility of treating cardiac arrhythmias by SBRT safety and noninvasively.

Usefulness of echocardiographic parameters in predicting the incidence of ischemic stroke in Japanese patients with non-valvular atrial fibrillation

Background

Atrial fibrillation (AF) is a risk factor for ischemic stroke (IS). We developed a novel risk score of IS (HELT-E2S2 score) in non-valvular atrial fibrillation (NVAF) patients from the combined database of 5 major AF registries in Japan. However, this score does not include echocardiographic (Echo) parameters that have been reported to be risk factors of IS, such as left atrial diameter (LAD) enlargement or increased relative wall thickness (RWT) of left ventricle (LV).

Purpose

To investigate the predictive value of Echo parameters in Japanese patients with NVAF.

Methods

After excluding patients without the Echo data, 6,032 NVAF patients were analyzed in the present study. LAD was measured in the parasternal long axis view at the end-ventricular systole. RWT was calculated as (2x posterior wall thickness)/ LV end-diastolic dimension. We compared clinical characteristics and the incidence of IS between NVAF patients divided by LAD level (High/Low LAD group) and RWT level (High/Low RWT group). To balance the follow-up period among the registries, event data from individuals whose follow-up period exceeded 730 days were excluded from the analysis.

Results

The optimal cut-off value of LAD and RWT to predict the incidence of IS with the receiver operating characteristic analysis was 43.3 mm and 0.4167, respectively. Between the High/Low LAD groups (High LAD: n=2,640 vs. Low LAD: n=3,392), age (70.3±12.1 vs. 68.3±12.5 years; p<0.001), CHA2DS2-VASc score (3.02±1.84 vs. 2.57±1.78; p<0.001), HELT-E2S2 score (2.20±1.31 vs. 1.55±1.33; p<0.001), the prescription of oral anticoagulants (OACs) (69.5 vs. 51.5%; p<0.001), LV ejection fraction (60.4±13.4 vs. 64.4±10.7%; p<0.001) and RWT (0.401±0.091 vs. 0.396±0.082; p=0.02) were significantly different. Between the High/Low RWT groups (High RWT: n=2,293 vs. Low RWT: n=3,739), percentage of female (35.6 vs. 27.8%; p<0.001), age (71.2±12.1 vs. 68.0±12.4 years; p<0.001), CHA2DS2-VASc score (3.08±1.82 vs. 2.58±1.79; p<0.001), HELT-E2S2 score (2.10±1.39 vs. 1.67±1.31; p<0.001), the prescription of OACs (62.6 vs. 57.4%; p<0.001), LV ejection fraction (65.5±9.9 vs. 60.9±13.0%; p<0.001) and LAD (43.0±8.1 vs. 42.4±8.3; p=0.004) were significantly different. In Kaplan-Meier analysis, the incidence of IS was different between the groups during the median follow-up period of 730 days (High LAD vs. Low LAD; 1.82 vs. 1.00 per 100 person-years; p<0.001, by log-rank test, High RWT vs. Low RWT; 1.86 vs. 1.06; p<0.001) (Figure). Both High LAD (hazard ratio: 1.65, 95% CI: 1.12–2.46; p=0.01) and High RWT (hazard ratio: 1.43, 95% CI: 1.01–2.04; p=0.045) were independent predictors of the incidence of IS after adjustment by the components of the HELT-E2S2 score and other clinically relevant variables including co-existing diseases, gender, and the prescription of OACs (Table).

Conclusion

Echo parameters, LAD and RWT, were independently associated with the incidence of IS among Japanese patients with NVAF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development

Therapeutic efficacy of intra-arterial docetaxel and nedaplatin infusion concomitant with radiotherapy for T4 maxillary sinus squamous cell carcinoma

The aim of this study was to evaluate the efficacy of intra-arterial chemoradiotherapy with docetaxel and nedaplatin for T4 maxillary sinus squamous cell carcinoma (MSSCC). Data were retrospectively analysed for 22 consecutive patients with T4 MSSCC who underwent intra-arterial chemoradiotherapy. Participants received intensity-modulated radiotherapy (70 Gy in 35 fractions) concomitantly with docetaxel (60 mg/m²) and nedaplatin (80 mg/m²) administered every 4 weeks for a total of three sessions. The median follow-up period was 49 months (range 12-91 months). T4a tumours were found in 16 patients (73%) and T4b tumours in six patients (27%). Cervical metastasis was found in nine patients (41%; five N2b, four N2c). The 5-year loco-regional control, disease-free survival, and overall survival rates for patients with T4a disease were 92.3%, 92.3%, and 90.3%, respectively, compared to 83.3% (P = 0.42), 66.7% (P = 0.07), and 83.3% (P = 0.46), respectively, for those with T4b disease. The 5-year loco-regional control, disease-free survival, and overall survival rates for patients with cervical lymph node metastasis were all 87.5% compared to 92.3% (P = 0.86), 84.6% (P = 0.69), and 92.3% (P = 0.93), respectively, for those without cervical metastasis. Intra-arterial chemoradiotherapy with docetaxel and nedaplatin may provide favourable loco-regional control and increased survival in T4 MSSCC.

Characterizing genetic variants for DAG and IP3 signalling pathways in severe cases of coronary spastic angina

Background

We previously reported that the activity of phospholipase C (PLC), a key molecule for intracellular calcium signaling, was enhanced in patients with coronary spastic angina (CSA). Furthermore, we found PLC-δ1 864 G to A mutation in about 10% of the male CSA patients. However, comprehensive understanding of genetic role in the pathogenesis of CSA remains to be elucidated.

Purpose

We tested the hypothesis that variants in the genes responsible for contraction signaling, especially a Ca2+-dependent mechanism, plays an important role in the pathogenesis of CSA.

Methods and results

Exome sequencing was performed to genotype comprehensively CSA cohort, enabling investigation of 258 gene network for diacylglycerol (DAG) and inositol trisphosphate (IP3) signallings, which are responsible for contraction signaling in the vascular smooth muscle cell (VSMC) by a Ca2+-dependent mechanism.

The study population included 30 Japanese patients with severe cases of CSA (18 men and 12 women with a mean age of 62.2±10.1 years). In 23 patients, ST segment elevation was recorded on the electrocardiogram during a spontaneous attack. In other 3 patients, ventricular fibrillation occurred following CSA attacks. The rests were diagnosed by ECG changes and elevated cardiac enzymes following CSA attacks. Genetic information from these CSA patients were compared with those from 914 healthy controls.

Frequencies of 17 common, functional polymorphisms of DAG and IP3 signallings were statistically similar to those of healthy controls. By high-quality (Call Quality ≥20, Read Depth ≥10), and predicted-deleterious (CADD score ≥20) filterings, the number of the candidate genes were narrowed from 234,445 to 17,738, and by selecting genes for DAG and IP3 signallings, further narrowed to 208 genes. Compared with 914 healthy controls, DAG and IP3 signalling genes revealed 26 variants in 15 genes in CSA cases, and by further filtering for rare (914 healthy control frequency <1%), 21 variants in 12 genes were found. They shared variants in G protein subunit alpha q (GNAQ), phospholipase C beta 3 (PLCB3), inositol 1,4,5-trisphosphate receptor type 3 (ITPR3), glutamate ionotropic receptor NMDA type subunit 2D (GRIN2D) in ≥5 cases. By filtering for high-quality, predicted-deleterious, and rare, genetic variants related with DAG and IP3 signalling were more found in severe CSA patients compared with healthy controls (CSA 4.33/person vs healthy controls 2.60 /person).

Conclusions

These findings indicate genetic heterogeneity in CSA susceptibility and a likely polygenic basis, giving a cumulative effect on DAG and IP3 signalling pathways in a subset of individual CSA patients. Study of larger cohorts is warranted to define genetic risk factors for CSA.

Funding Acknowledgement

Type of funding source: None

An experimental setup for creating and imaging 4He2 * excimer cluster tracers in superfluid helium-4 via neutron-3He absorption reaction

For the purpose of future visualization of the flow field in superfluid helium-4, clusters of the triplet state excimer ⁴He₂ ^* are generated along the micro-scale recoil tracks of the neutron-absorption reaction n + ³He → ³T + p. This reaction is induced by neutron irradiation of the ³He fraction contained in natural isotopic abundance liquid helium with neutron beams either from the Japan Proton Accelerator Research Complex, Materials and Life Science Experimental Facility (JPARC)/Materials and Life Science Experimental Facility or from the Kyoto University Institute for Integrated Radiation and Nuclear Science. These ⁴He₂ ^* clusters are expected to be ideal tracers of the normal-fluid component in superfluid helium with several advantageous properties. Evidence of the excimer generation is inferred by detection of laser induced fluorescence emitted from the ⁴He₂ ^* clusters excited by a purpose-built short pulse gain-switched titanium:sapphire (Ti:sa) laser operating at a wavelength of 905 nm. The setup and performance characteristics of the laser system including the Ti:sa and two continuous wave re-pumping lasers are described. Detection at the fluorescence wavelength of 640 nm is performed by using optical bandpass filtered photomultiplier tubes (PMT). Electrical noise in the PMT acquisition traces could successfully be suppressed by post-processing with a simple algorithm. Despite other laser-related backgrounds, the excimer was clearly identified by its fluorescence decay characteristics. Production of the excimer was found to be proportional to the neutron flux, adjusted via insertion of different collimators into the neutron beam. These observations suggest that the apparatus we constructed does function in the expected manner and, therefore, has the potential for groundbreaking turbulence research with superfluid helium.

P856Incidence and Outcomes of irregular protrusion after stent implantation in patients with acute myocardial infarction: An in in vivo optical coherence tomography study

Background

Irregular protrusion, a protrusion of material with an irregular surface into the lumen of the vessel after stent implantation, can only be identified by optical coherence tomography (OCT). A previous study demonstrated that irregular protrusion after stent implantation was an independent predictor of 1-year major adverse cardiac events (MACE) in CAD patients. However, the true incidence and prognostic significance of irregular protrusion after stenting in patients with ST-segment elevation myocardial infarction (STEMI) have not previously examined.

Aims

The aims of this study were the following: 1) to evaluate the incidence of irregular protrusion detected by OCT in STEMI patients after stenting; and 2) to compare the long-term outcomes between patients with and without irregular protrusion.

Methods and results

A total of 210 STEMI patients who had post-procedure OCT imaging after coronary stenting within 12 hours after symptom onset were studied. We divided them into two groups: those with irregular protrusion (n=159) and those without (n=51) after stenting. There were no significant differences in baseline characteristics between the 2 groups except that peak CK-MB levels were higher in patients with irregular protrusion than those without (289 (137–563) vs. 260 (63–349) U/L, p<0.05). During mean follow-up period of 298 days, the overall incidence of MACE defined as cardiac death, target vessel-related myocardial infarction, and target lesion revascularization was 15.3%. Kaplan-Meier curve showed that the incidence of MACE did not differ between patients with and without irregular protrusion (14.7% vs. 17.7%, p=0.53 by Log-rank).

Conclusions

Irregular protrusion after stent implantation was detected in three-fourth of STEMI patients. Although patients with irregular protrusion had a greater myocardial damage, it did not influence clinical outcomes.

Acknowledgement/Funding

Donation course from Abbott Japan

P3755Left atrial enlargement as an independent risk factor for ischemic stroke in Japanese atrial fibrillation patients: pooled analysis of five major Japanese atrial fibrillation registries

Background

Atrial fibrillation (AF) increases the risk of ischemic stroke. It remains unknown whether left atrial diameter determined by routine trans-thoracic echocardiography is a risk factor for ischemic stroke in non-valvular AF (NVAF) patients.

Purpose

The aim of this study is to investigate the impact of left atrial enlargement (LAE) on the incidence of ischemic stroke in a large-scale cohort of Japanese NVAF patients.

Methods

We combined the data of 5 major AF registries in Japan, J-RHYTHM Registry, Fushimi AF Registry, Shinken Database, Keio interhospital Cardiovascular Studies, and Hokuriku AF Registry. After excluding patients without echocardiographic data, 7,672 NVAF patients were analyzed in the present study (mean age, 69.3±12.3 years; mean CHADS2 score, 1.6±1.3). We compared clinical characteristics and the incidence of ischemic stroke between NVAF patients with LAE (left atrial diameter >45 mm; LAE group) and those without (non-LAE group).

Results

The mean left atrial diameter was 43.1±8.6 mm, and the LAE group accounted for 40.0% (n=3,066) of the entire cohort. Compared with non-LAE group (60.0%, n=4,606), the LAE group was older (LAE vs. non-LAE; 70.3±12.0 vs. 68.0±12.5, p<0.01), more often non-paroxysmal type (73.7% vs. 32.1%, p<0.01), had higher CHADS2 (1.86±1.34 vs. 1.46±1.29, p<0.01) and CHA2DS2-VASc (3.02±1.83 vs. 2.53±1.78, p<0.01) scores, and more frequently received oral anticoagulant (72.9% vs. 55.0%, p<0.01).

During the median follow-up period of 774.5 days (interquartile range: 567–1466 days), ischemic stroke occurred in 241 patients (131 vs. 110 patients; 1.52 vs. 0.82 per 100 person-years). In Kaplan Meier analysis, LAE was associated with a higher incidence of ischemic stroke (unadjusted hazard ratio (HR): 1.83, 95% confidence interval (CI): 1.42–2.36; log rank p<0.01) (Figure). LAE was independently associated with increased risk of ischemic stroke (adjusted HR: 1.63, 95% CI: 1.25–2.11; p<0.01) after adjustment by the components of CHADS2 score and the use of oral anticoagulant, on multivariate Cox proportional hazard analysis.

Conclusion

In this large-scale cohort of Japanese patients with AF, LAE was an independent predictor of ischemic stroke, suggesting that this simple echocardiographic parameter could refine thromboembolic risk stratification of NVAF patients.

Acknowledgement/Funding

Japan Agency for Medical Research and Development, AMED

P2565Decreased cardiac pacemaking and attenuated beta-adrenergic response in tric-a knock-out mice

Background

Trimeric intracellular cation (TRIC) channels are expressed on the surface of the sarcoplasmic reticulum and compensate for calcium release from ryanodine receptors. Tric-a knock-out (KO) mice showed diminished calcium release from ryanodine receptors in vascular smooth muscle cells. The cardiac pacemaker is controlled by the surface membrane and intracellular calcium clocks. In spontaneously firing sinus node action potentials, the membrane and calcium clocks work together via numerous interactions modulated by membrane voltage, intracellular calcium release, and protein phosphorylation. Intracellular calcium changes modulate cardiac pacemaking in the sinus node, but the physiological importance of TRIC channels in cardiac rhythm formation is still obscure.

Purpose

In this study, we aimed to clarify the importance of TRIC channels on cardiac pacemaking using Tric-a KO mice.

Methods

The expression level of mRNA and proteins in the sinus node was examined by RT-PCR and immunoblotting. Systolic blood pressure was measured with tail-cuff method. Heart rate was measured by ECG, and heart rate variability was examined. The atrial contractile force from isolated hearts was measured with a force transducer. Cardiac action potential and spontaneous sinus rate from isolated hearts were measured with a microelectrode. Isoproterenol was used for sympathetic nerve manipulation.

Results

Tric-a KO heart showed increased adrenergic β1-receptor expression in immunoblotting. Although there was no significant difference in basal systolic blood pressure between Tric-a KO and wild type (WT) mice, basal heart rate in Tric-a KO mice was significantly lower than that in WT mice (660±10 and 698±10 bpm, n=15 and 19, Tric-a KO mice and WT mice, respectively, p=0.017). Tric-a KO mice showed limited heart rate changes to isoproterenol (24±6 and 99±15 bpm, n=9 and 10, Tric-a KO mice and WT mice, respectively, p<0.001). In the action potential recordings, Tric-a KO atria showed only limited sinus rate changes to isoproterenol (35±9 and 71±10 bpm, n=8 and 6, Tric-a KO mice and WT mice, respectively, p=0.038). WT mice and Tric-a KO mice atrial contractile force showed dose-dependent changes in response to isoproterenol (10–100 nM), but Tric-a KO mice atria showed limited contractile force changes to isoproterenol (116 and 169%, n=7 and 6, Tric-a KO mice and WT mice, respectively, p<0.01). In heart rate variability, Tric-a KO mice showed unstable RR intervals and longer standard deviation of RR intervals than WT mice.

Conclusion

Tric-a KO mice showed decreased cardiac pacemaking in the sinus node and attenuated responses to beta-adrenergic stimulus, which indicates the involvement of TRIC channels in cardiac rhythm formation and sympathetic nerve regulation.

P1624Blockade of protease activated receptor-1 signaling attenuates cardiac hypertrophy and fibrosis in renin-overexpressing hypertensive mice

Introduction

Recent evidences have demonstrated that coagulation pathway is involved in cardiovascular remodeling induced by renin-angiotensin system (RAS), which finally leads to heart failure. Protease activated receptor-1 (PAR-1) is widely expressed in the vasculature and the heart, and plays important roles in pro-inflammatory process in the cardiovascular system. Recently, we demonstrated that the activity of factor Xa (FXa), which functions not only as a coagulation factor but as an agonist for PAR-1, was enhanced in renin-overexpressing hypertensive mice (Ren-Tg).

Purpose

The purpose of this study was to investigate whether inhibition of PAR-1 signaling has protective effects on the progression of heart failure induced by chronic RAS activation in Ren-Tg.

Methods and results

We treated 12–16 weeks-old male wild type mice (WT) and Ren-Tg with continuous subcutaneous infusion of PAR-1 antagonist SCH79797 (25mg/kg/day) or vehicle for 4 weeks. After treatment period, left ventricular (LV) wall thickness calculated as interventricular septum plus posterior wall thickness measured by echocardiography was greater in Ren-Tg than in WT (0.25±0.003 versus 0.18±0.002 mm), and SCH79797 attenuated the increase to 0.22±0.01 mm in Ren-Tg (both p<0.05, respectively). The ratio of heart weight to body weight was greater in Ren-Tg than in WT (6.1±0.4 versus 4.6±0.7 mg/g), and SCH79797 attenuated the increase to 5.2±0.1 mg/g (both p<0.05). The area of cardiac fibrosis evaluated by Masson-trichrome staining was greater in Ren-Tg than in WT (2.6±0.2 versus 1.4±0.3%), and SCH79797 attenuated it to 1.6±0.3% in Ren-Tg (both p<0.05). Cardiac mRNA expressions of tumor necrosis factor-α, transforming growth factor-β1, and β-myosin heavy chain were all greater in Ren-Tg than in WT, and SCH79797 attenuated the increases in Ren-Tg (all p<0.05).

Conclusions

Inhibition of PAR-1 signaling attenuates cardiac hypertrophy and fibrosis in Ren-Tg via inhibition of inflammatory cytokines production. These results support the involvement of PAR signaling in the development of heart failure induced by RAS, and may provide novel therapeutic insights for the treatment of hypertensive heart failure.

Partial Cystectomy of Paraganglioma of the Urinary Bladder Before Living Kidney Transplantation: Case Report

BACKGROUND

Paraganglioma (extra-adrenal pheochromocytoma) of the bladder is a very rare disease, accounting for 0.06% of all bladder tumors. Optimal management of bladder paraganglioma before kidney transplantation is unknown. We report a case of partial cystectomy for urinary bladder paraganglioma before living kidney transplantation.

CASE PRESENTATION

A 59-year-old man with a 27-year history of hemodialysis was referred to our department for further examination of a bladder tumor detected during pre-transplantation testing. Cystoscopy revealed a submucosal tumor on the right side of the bladder. The patient experienced a hypertensive crisis during transurethral resection of the bladder tumor. Endocrinologic and pathologic examinations confirmed the diagnosis of paraganglioma in the urinary bladder. A partial cystectomy was performed before kidney transplantation. Nine months after partial cystectomy, the patient underwent AB0-incompatible living kidney transplantation from his spouse. No disease recurrence or graft rejection was observed 12 months after the transplantation.

CONCLUSIONS

To our knowledge, this is the 1st report on the management of paraganglioma in the urinary bladder before living kidney transplantation. Kidney transplantation after partial cystectomy is an option that may be considered in patients with paraganglioma of the urinary bladder, with careful observations of bladder function and vesicoureteral reflux to the grafts.

Condyloma Acuminata of the Urethra in a Male Renal Transplant Recipient: A Case Report

BACKGROUND

Condyloma acuminatum (CA) is a common sexually transmitted disease associated with human papilloma virus (HPV). CA occurring in the urethra is rare and has not been reported in male renal transplant recipients. In addition, despite immunosuppressive conditions and increased risk of HPV-related malignant neoplasms in transplant recipients, HPV testing in male transplant recipients has been uncommon. Here we report a case of urethral CA in a male deceased donor renal transplantation recipient and discuss the importance of HPV testing in male transplant recipients.

CASE PRESENTATION

A 33-year-old male deceased donor renal transplant recipient presented with miction pain 5 years after the transplantation. He reported repeated urinary tract infections with no sexual contact since the renal transplantation. Multiple papillary tumors in his penile urethra were detected by cystoscopy, and a biopsy sample was pathologically diagnosed with CA. Transurethral tumor resection was performed, and the tumors were completely resected. Additional HPV risk type screening with a urethral smear sample showed the prevalence of low-risk HPV. Although tacrolimus was switched to everolimus and imiquimod cream was administered, the tumors recurred 6 months after the resection, and a second resection was performed. No further recurrence has been observed for 1 year to date.

CONCLUSION

As the urethral CA was possibly related to immunosuppressive conditions and a risk for HPV-related malignant neoplasm, the case required careful diagnosis, including HPV risk type. The methodology of sampling for HPV testing in men has not been established. This case suggests the necessity for further discussion about HPV testing in male transplant recipients.

5-Hydroxy-2-methylpyridine Isolated from Cigarette Smoke Condensate Aggravates Collagen-Induced Arthritis in Mice

The risk of rheumatoid arthritis (RA) is linked to environmental and genetic factors. Cigarette smoking is an established environmental risk factor for the disease that contributes to its development and severity. Previously, we found that cigarette smoke condensate (CSC), both mainstream and sidestream, aggravates collagen type II-induced arthritis (CIA), which was observed following either intraperitoneal inoculation or nasal exposure. In the present study, we aimed to identify the compound in CSC, which aggravates CIA. By sequential fractionation and analysis, extraction with water/ether in different pH values, silica gel column chromatography, TLC, octadecyl silica (ODS) HPLC, GC/MS, and NMR, the active compound was identified as 5-hydroxy-2-methylpyridine (5H2MP). Its isomer 2-hydroxy-3-methylpyridine, but not 3-hydroxy-2-methylpyridine, was also active. 5H2MP was not mutagenic, and did not exhibit aryl hydrocarbon receptor-dependent activity. Our data help clarify the mechanism underlying the pathogenic effects of cigarette smoking on RA.

Development of fast neutron pinhole camera using nuclear emulsion for neutron emission profile measurement in KSTAR

We have developed a compact fast neutron camera based on a stack of nuclear emulsion plates and a pinhole collimator. The camera was installed at J-port of Korea superconducting tokamak advanced research at National Fusion Research Institute, Republic of Korea. Fast neutron images agreed better with calculated ones based on Monte Carlo neutron simulation using the uniform distribution of Deuterium-Deuterium (DD) neutron source in a torus of 40 cm radius.

Unemployment risk among individuals undergoing medical treatment for chronic diseases

BACKGROUND

Chronic diseases increase the risk of unemployment even in non-disaster settings; therefore, in post-disaster settings, special attention needs to be paid to the employment status of those suffering from chronic diseases.

AIMS

To examine the association between chronic disease and the risk of unemployment in a disaster area.

METHODS

This cross-sectional study was conducted in Shichigahama Town, Miyagi, north-eastern Japan, where had been severely inundated by the 2011 tsunami. Logistic regression analyses were used to evaluate the association between undergoing medical treatment for a combination of chronic diseases (stroke, cancer, myocardial infarction and angina) and unemployment risk. Confounders such as psychological distress and levels of daily life activity were considered.

RESULTS

Among the 2588 individuals studied, there was a statistically significant association between undergoing medical treatment for chronic disease and the risk of unemployment [odds ratio (OR) = 1.7, 95% confidence interval (CI) 1.02-2.7, P < 0.05]. In participants with a lower degree of psychological distress and better levels of daily life activity (n = 1967), no significant associations were observed (OR = 1.1, 95% CI 0.6-2.1). Conversely, in 536 participants with a higher degree of psychological distress and/or poorer levels of daily life activity, statistically significant associations were found (OR = 2.6, 95% CI 1.01-6.6, P < 0.05).

CONCLUSIONS

The association between undergoing medical treatment for chronic disease and unemployment risk was observed only in participants with a higher degree of psychological distress and/or poorer levels of daily life activity.

A study on fast digital discrimination of neutron and gamma-ray for improvement neutron emission profile measurement

Neutron and γ-ray (n-γ) discrimination with a digital signal processing system has been used to measure the neutron emission profile in magnetic confinement fusion devices. However, a sampling rate must be set low to extend the measurement time because the memory storage is limited. Time jitter decreases a discrimination quality due to a low sampling rate. As described in this paper, a new charge comparison method was developed. Furthermore, automatic n-γ discrimination method was examined using a probabilistic approach. Analysis results were investigated using the figure of merit. Results show that the discrimination quality was improved. Automatic discrimination was applied using the EM algorithm and k-means algorithm.

Progress in development of neutron energy spectrometer for deuterium plasma operation in KSTAR

Two types of DD neutron energy spectrometer (NES) are under development for deuterium plasma operation in KSTAR to understand behavior of beam ions in the plasma. One is based on the state-of-the-art nuclear emulsion technique. The other is based on a coincidence detection of a recoiled proton and a scattered neutron caused by an elastic scattering of an incident DD neutron, which is called an associated particle coincidence counting-NES. The prototype NES systems were installed at J-port in KSTAR in 2012. During the 2012 and 2013 experimental campaigns, multiple shots-integrated neutron spectra were preliminarily obtained by the nuclear emulsion-based NES system.

Progress in development of the neutron profile monitor for the large helical device

The neutron profile monitor stably operated at a high-count-rate for deuterium operations in the Large Helical Device has been developed to enhance the research on the fast-ion confinement. It is composed of a multichannel collimator, scintillation-detectors, and a field programmable gate array circuit. The entire neutron detector system was tested using an accelerator-based neutron generator. This system stably acquires the pulse data without any data loss at high-count-rate conditions up to 8 × 10(5) counts per second.

Highly sensitive nanoscale spin-torque diode

Highly sensitive microwave devices that are operational at room temperature are important for high-speed multiplex telecommunications. Quantum devices such as superconducting bolometers possess high performance but work only at low temperature. On the other hand, semiconductor devices, although enabling high-speed operation at room temperature, have poor signal-to-noise ratios. In this regard, the demonstration of a diode based on spin-torque-induced ferromagnetic resonance between nanomagnets represented a promising development, even though the rectification output was too small for applications (1.4 mV mW(-1)). Here we show that by applying d.c. bias currents to nanomagnets while precisely controlling their magnetization-potential profiles, a much greater radiofrequency detection sensitivity of 12,000 mV mW(-1) is achievable at room temperature, exceeding that of semiconductor diode detectors (3,800 mV mW(-1)). Theoretical analysis reveals essential roles for nonlinear ferromagnetic resonance, which enhances the signal-to-noise ratio even at room temperature as the size of the magnets decreases.

Notch signaling pathway regulates proliferation and differentiation of immortalized Müller cells under hypoxic conditions in vitro

Previous studies have indicated that Müller glia in chick and fish retinas can re-enter the cell cycle, express progenitor genes, and regenerate neurons via the Notch signaling pathway in response to retinal damage or growth factors. Here, we investigated the role of Notch signaling and the effect of hypoxia, as a means to induce retinal damage, on the proliferation of an immortalized Müller cell line (rMC-1 cells). Our data showed that rMC-1 cells expressed Müller glia and neural and retinal progenitor markers but did not express neuronal or retinal markers. Hypoxia increased rMC-1 cell proliferation by activating the positive cell-cycle regulators, cyclins A and D1, as well as the neural and retinal progenitor markers, Notch1, Hes1, nestin, Sox2, Msi1, Pax6, and NeuroD1. However, hypoxia did not significantly influence the expression of Müller glial markers GS, CRALBP, and cyclin D3 or the death of the rMC-1 cells. The increase in cell proliferation induced by hypoxia was greatly attenuated by blocking Notch signaling with the inhibitor DAPT, resulting in the reduced expression of positive cell-cycle regulators (cyclins A and D1) and neural and retinal progenitor markers (Notch1, Hes1, Sox2, Pax6, and NeuroD1). Blockade of the Notch signaling pathway by DAPT after hypoxia promoted the differentiation of rMC-1 cells to neurons, as demonstrated by the induction of neural marker (Tuj1), retinal amacrine (Syntaxin1), and retinal ganglion cell (Brn3b) markers, although the expression of the latter marker was low. Taken together, our data indicate that Notch signaling is required for proliferation under hypoxic conditions either by activating the positive cell-cycle regulators or by skewing their de-differentiation towards a neural progenitor lineage. These findings indicate that the Notch signaling pathway regulates hypoxia-induced proliferation and differentiation of Müller glia.

Coupling factor 6-induced activation of ecto-F1F(o) complex induces insulin resistance, mild glucose intolerance and elevated blood pressure in mice

AIMS/HYPOTHESIS

Despite advances in pharmacological treatments, diabetes with hypertension continues to be a major public health problem with high morbidity and mortality rates. We recently identified a circulating peptide coupling factor 6 (CF6), which binds to the plasma membrane ATP synthase (ecto-F(1)F(o) complex), resulting in intracellular acidosis. We investigated whether overexpression of CF6 contributes to diabetes and hypertension by intracellular acidosis.

METHODS

Transgenic mice overexpressing CF6 (also known as ATP5J) were generated, and physiological, biochemical and molecular biology studies were performed.

RESULTS

CF6 overexpression elicited a sustained decrease in intracellular pH in tissues (aorta, kidney, skeletal muscle and liver, with the exception of adipose tissue) that express its receptor, the β-subunit of ecto-F(1)F(o) complex. Consistent with the receptor distribution, phospho-insulin receptor β, phosphoinositide 3-kinase activity and the phospho-Akt1:total Akt1 ratio were all decreased in the skeletal muscle and the liver in transgenic compared with wild-type mice, resulting in a decrease of plasma membrane-bound GLUT4 and an increase in hepatic glucose production. Under a high-sucrose diet, transgenic mice had insulin resistance and mild glucose intolerance; under a high-salt diet, they had elevated blood pressure with increased renal RAS-related C3 botulinum substrate 1 (RAC1)-GTP, which is an activator of mineralocorticoid receptor.

CONCLUSIONS/INTERPRETATION

Through its action on the β-subunit of ecto-F(1)F(o) complex, which results in intracellular acidosis, CF6 plays a crucial role in the development of insulin resistance and hypertension. This finding might advance our understanding of the mechanisms underlying diabetes and hypertension, possibly also providing a novel therapeutic target against cardiovascular disease.

Molecular characterization of erm(B)- and mef(E)-mediated erythromycin-resistant Streptococcus pneumoniae in China and complete DNA sequence of Tn2010

AIMS

To characterize the erm(B)- and mef(E)-mediated erythromycin-resistant Streptococcus pneumoniae clinical isolates obtained from ten hospitals located different cities in China.

METHODS AND RESULTS

Totally 83 S. pneumoniae were collected, and eighteen representative strains of 66 strains that exhibited erythromycin resistance were used for further characterization by antibiograms, serotyping, PFGE, MLST, DNA sequencing of the macrolide-resistance elements and mapping of the elements on the chromosome. Twelve isolates showed a high-level resistance to erythromycin, and six other isolates showed a low-level resistance to erythromycin. Thirteen isolates harboured a Tn2010 transposon (26·4 kbp) encoding the erm(B), tet(M) and mef(E) genes and were classified into three types by Tn2010 structures. The remaining five isolates harboured a Tn6002 transposon (20·9 kbp) encoding the erm(B) and tet(M) genes and were classified into three types by Tn6002 locations on the chromosome. Three of the Tn6002 elements were located within the Tn5252-like element, implying that these composed a large mobile element. The MLST analyses showed that several clones had been disseminated and that the CC271 strains carrying the Tn2010 element expressing the high-level resistance to erythromycin were predominant in China. Four new MLST strains, which were designated as ST3262, ST3263, ST3397 and ST3398 were also identified.

CONCLUSIONS

The erythromycin resistance determinant of S.pneumoniae that had been isolated in China was located in Tn2010 or the Tn6002 element and several clones had been disseminated, and the CC271 strains carrying the Tn2010 element expressing the high-level resistance to erythromycin were predominant in China.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first molecular analysis of erythromycin-resistant Streptococcus pneumoniae clinical isolates in China, and the first report of the complete nucleotide sequence of Tn2010 (26,390 bp).

Fusion product diagnostics planned for Large Helical Device deuterium experiment

Deuterium experiment on the Large Helical Device (LHD) is now being planned at the National Institute for Fusion Science. The fusion product diagnostics systems currently considered for installation on LHD are described in this paper. The systems will include a time-resolved neutron yield monitor based on neutron gas counters, a time-integrated neutron yield monitor based on activation techniques, a multicollimator scintillation detector array for diagnosing spatial distribution of neutron emission rate, 2.5 MeV neutron spectrometer, 14 MeV neutron counter, and prompt γ-ray diagnostics.

Development of neutron spectrometer toward deuterium plasma diagnostics in LHD

Neutron spectrometer based on coincident counting of associated particles has been developed for deuterium plasma diagnostics on Large Helical Device (LHD) at the National Institute for Fusion Science. Efficient detection of 2.5 MeV neutron with high energy resolution would be achievable by coincident detection of a scattered neutron and a recoiled proton associated with an elastic scattering of incident neutron in a plastic scintillator as a radiator. The calculated neutron spectra from deuterium plasma heated by neutral beam injection indicate that the energy resolution of better than 7% is required for the spectrometer to evaluate energetic deuterium confinement. By using a prototype of the proposed spectrometer, the energy resolution of 6.3% and the detection efficiency of 3.3×10(-7) count/neutron were experimentally demonstrated for 2.5 MeV monoenergetic neutron, respectively.

The first molecular analysis of clinical isolates of VanA-type vancomycin-resistant Enterococcus faecium strains in Mainland China

AIMS

The aim of this study was to examine two VanA-type vancomycin-resistant Enterococcus faecium (VRE) strains that had been isolated from patients resident in mainland China. This is the first molecular analysis of clinical VRE strains being isolated in mainland China.

METHODS AND RESULTS

Two VanA-type VRE isolates were isolated from in-patients at hospitals located in the Chinese cities Beijing and Dalian and were designated C264 and I125. The plasmids pC264V (40 kbp) and pI125V (370 kbp) that were isolated from C264 and I125, respectively, carried a Tn1546-like element encoding VanA resistance. The vancomycin-resistant plasmids pC264V and pI125V were transferred by filter mating at frequencies of 10(-7) and 10(-4) respectively. Sequence analysis of pC264V revealed that two IS1216V sequences and an IS1542 sequence were present within the Tn1546-like element. pI125V had two IS1216V insertions in the Tn1546-like element.

CONCLUSIONS

The two VanA-type vancomycin-resistant E. faecium (VRE) strains C264 and I125 were isolated from in-patients in Chinese hospitals. The vancomycin-resistant conjugative plasmids pC264V and pI125V plasmids isolated from these strains carried the Tn1546-like element. The Tn1546-like element was found to contain the insertion sequences IS1216V and IS1542.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first molecular analysis of VanA-type VRE strains from patients resident in mainland China.

Blunt renal trauma: Comparison of contrast-enhanced CT and angiographic findings and the usefulness of transcatheter arterial embolization

Background: The purpose of this study was to evaluate the role of contrast-enhanced CT and the usefulness of superselective embolization therapy in the management of arterial damage in patients with severe blunt renal trauma. Patients and methods: Nine cases of severe renal trauma were evaluated. In all cases, we compared contrast-enhanced CT findings with angiographic findings, and performed transcatheter arterial embolization (TAE) in six of them with microcoils and gelatin sponge particles. Morphological changes in the kidney and site of infarction after TAE were evaluated on follow-up CT. Chronological changes in blood biochemistry findings after injury, degree of anemia and renal function were investigated. Adverse effects or complications such as duration of hematuria, fever, abdominal pain, renovascular hypertension and abscess formation were also evaluated. Results: The CT finding of extravasation was a reliable sign of active bleeding and useful for determining the indication of TAE. In all cases, bleeding was effectively controlled with superselective embolization. There was minimal procedure-related loss of renal tissue. None of the patients developed abscess, hypertension or other complications. Conclusions: In blunt renal injury, contrast-enhanced CT was useful for diagnosing arterial hemorrhage. Arterial bleeding may produce massive hematoma and TAE was a useful treatment for such cases. By using selective TAE for a bleeding artery, it was possible to minimize renal parenchymal damage, with complications of TAE rarely seen.

Mitochondrial-related gene expression changes are sensitive to agonal-pH state: implications for brain disorders

Mitochondrial defects in gene expression have been implicated in the pathophysiology of bipolar disorder and schizophrenia. We have now contrasted control brains with low pH versus high pH and showed that 28% of genes in mitochondrial-related pathways meet criteria for differential expression. A majority of genes in the mitochondrial, chaperone and proteasome pathways of nuclear DNA-encoded gene expression were decreased with decreased brain pH, whereas a majority of genes in the apoptotic and reactive oxygen stress pathways showed an increased gene expression with a decreased brain pH. There was a significant increase in mitochondrial DNA copy number and mitochondrial DNA gene expression with increased agonal duration. To minimize effects of agonal-pH state on mood disorder comparisons, two classic approaches were used, removing all subjects with low pH and agonal factors from analysis, or grouping low and high pH as a separate variable. Three groups of potential candidate genes emerged that may be mood disorder related: (a) genes that showed no sensitivity to pH but were differentially expressed in bipolar disorder or major depressive disorder; (b) genes that were altered by agonal-pH in one direction but altered in mood disorder in the opposite direction to agonal-pH and (c) genes with agonal-pH sensitivity that displayed the same direction of changes in mood disorder. Genes from these categories such as NR4A1 and HSPA2 were confirmed with Q-PCR. The interpretation of postmortem brain studies involving broad mitochondrial gene expression and related pathway alterations must be monitored against the strong effect of agonal-pH state. Genes with the least sensitivity to agonal-pH could present a starting point for candidate gene search in neuropsychiatric disorders.

Enhanced therapeutic efficacy of G207 for the treatment of glioma through Musashi1 promoter retargeting of gamma34.5-mediated virulence

G207 is a conditionally replicating derivative of herpes simplex virus type1 (HSV-1) engineered with deletions of both ICP34.5 loci and a lacZ insertion disabling the ICP6 gene. G207 exhibits an efficient oncolytic activity in vitro and in vivo, yet minimal toxicity in normal tissue, and is now in clinical trial for malignant glioma. According to the results of clinical trials, however, although G207 was proved to be safe, the efficacy was not so impressive. Deletion of the ICP34.5 gene coding for virulence made G207 extremely safe, but it markedly reduced the cytotoxicity mediated by HSV-1. To enhance the therapeutic efficacy of G207 without diminishing its safety, we used a defective vector containing Musashi1 promoter/ICP34.5, with G207 as helper virus. P/musashi1 was functional selectively in human glioma cell lines (U87MG, U251, T98G) in this study and dvM345 showed a much higher therapeutic efficacy both in culture and in the in vivo glioma model, than G207 alone, without diminishing its favorable toxicity profile. These results suggest that transcriptional regulation of ICP34.5 by P/musashi1 can be used to target HSV-1 virulence toward gliomas while maintaining the desirable neuroattenuated phenotype.

Coil Embolization for Ruptured Cerebral Aneurysms of 2x3 mm Diameter

SUMMARY

Small ruptured cerebral aneurysms, such as those of 2x3 mm diameter, are considered to be difficult to embolize by detachable coils because of the risk of procedural perforation of the aneurysms. We have treated these small aneurysms and report the techniques and pitfalls of these embolizations. Twenty-four patients with ruptured cerebral aneurysms of 2x3 mm diameter were intended for treatment by coil embolization. Before coil embolization, three-dimensional digital subtraction angiography was performed, and the simulation of the volume embolization ratio (VER) was performed in all patients, except for the first basilar artery aneurysm patient. The tip of the microcatheter was steam-shaped several times and was placed on the neck of the aneurysm. A balloon neck remodeling technique was used for two aneurysms. GDC 10 softs and soft SRs were used for the first ten aneurysms, and Ultrasofts were used for the last eleven aneurysms. Out of twentyfour aneurysm embolizations, we aborted the procedure in three cases, because of a failure in catheterization; we performed clipping surgery for these cases. For the first case of a basilar tip aneurysm, the aneurysm was perforated, due to the use of too long a coil and the insertion of the tip of the microcatheter into the aneurysmal dome. Minor infarction occurred in one patient. The mean VER was 33.9%, and two aneurysms recanalized, and out of these one needed a second embolization. Six months postoperatively, 81% of patients had made in a good recovery or had a moderate disability.We recommend the following techniques to embolize aneurysms of 2x3 mm diameter: the tip of the microcatheter should be stabilized on the aneurysmal neck by steam shaping of the microcatheter, GDC 10 soft and Ultrasoft should be selected for use, and the simulation of the VER should be performed before embolization to select coils of a suitable length.