Molecular mechanism of formation and destruction of a pseudo‑capsule in clear cell renal cell carcinoma

The process and molecular mechanisms underlying the formation and destruction of a pseudo-capsule (PC) in clear cell renal cell carcinoma (ccRCC) are poorly understood. In the present study, the PCs of surgical specimens from primary tumors and metastatic lesions in 169 patients with ccRCC, and carcinogen-induced ccRCC rat models were semi-quantified using the invasion of PC (i-Cap) score system. This was based on the relationship among the tumor, PC and adjacent normal tissue (NT) as follows: i-Cap 0, tumor has no PC and does not invade NT; i-Cap 1, tumor has a complete PC and does not invade into the PC; i-Cap 2, tumor with focal absences in the PC, which partially invades the PC but not completely through the PC; i-Cap 3, tumor crosses the PC and invades the NT; i-Cap 4, tumor directly invades the NT without a PC. The study suggested that PC formation was not observed without physical compression, and also revealed that tumor invasion into the PC was a prognostic factor for postoperative oncological outcomes. Higher i-Cap, Fuhrman grade and tumor size were independent poor prognostic factors for postoperative disease-free survival. mRNA expression arrays generated from carcinogen-induced ccRCC rat models were used to explore genes potentially associated with the formation and destruction of a PC. Subsequently, human ccRCC specimens were validated for four genes identified via expression array; the results revealed that collagen type 4A2, matrix metalloproteinase-7 and l-selectin were upregulated alongside the progression of i-Cap score. Conversely, endoglin was downregulated. In conclusion, the present study provides insights into the formation and destruction of a PC, and the results may aid the treatment and management of patients with ccRCC.

A landscape of complex tandem repeats within individual human genomes

Markedly expanded tandem repeats (TRs) have been correlated with ~60 diseases. TR diversity has been considered a clue toward understanding missing heritability. However, haplotype-resolved long TRs remain mostly hidden or blacked out because their complex structures (TRs composed of various units and minisatellites containing >10-bp units) make them difficult to determine accurately with existing methods. Here, using a high-precision algorithm to determine complex TR structures from long, accurate reads of PacBio HiFi, an investigation of 270 Japanese control samples yields several genome-wide findings. Approximately 322,000 TRs are difficult to impute from the surrounding single-nucleotide variants. Greater genetic divergence of TR loci is significantly correlated with more events of younger replication slippage. Complex TRs are more abundant than single-unit TRs, and a tendency for complex TRs to consist of <10-bp units and single-unit TRs to be minisatellites is statistically significant at loci with ≥500-bp TRs. Of note, 8909 loci with extended TRs (>100b longer than the mode) contain several known disease-associated TRs and are considered candidates for association with disorders. Overall, complex TRs and minisatellites are found to be abundant and diverse, even in genetically small Japanese populations, yielding insights into the landscape of long TRs.

Phase-separated nuclear bodies of nucleoporin fusions promote condensation of MLL1/CRM1 and rearrangement of 3D genome structure

NUP98 and NUP214 form chimeric fusion proteins that assemble into phase-separated nuclear bodies containing CRM1, a nuclear export receptor. However, these nuclear bodies' function in controlling gene expression remains elusive. Here, we demonstrate that the nuclear bodies of NUP98::HOXA9 and SET::NUP214 promote the condensation of mixed lineage leukemia 1 (MLL1), a histone methyltransferase essential for the maintenance of HOX gene expression. These nuclear bodies are robustly associated with MLL1/CRM1 and co-localized on chromatin. Furthermore, whole-genome chromatin-conformation capture analysis reveals that NUP98::HOXA9 induces a drastic alteration in high-order genome structure at target regions concomitant with the generation of chromatin loops and/or rearrangement of topologically associating domains in a phase-separation-dependent manner. Collectively, these results show that the phase-separated nuclear bodies of nucleoporin fusion proteins can enhance the activation of target genes by promoting the condensation of MLL1/CRM1 and rearrangement of the 3D genome structure.

The arginine transporter Can1 acts as a transceptor for regulation of proline utilization in the yeast Saccharomyces cerevisiae

Proline is the most abundant amino acid in wine and beer, because the yeast Saccharomyces cerevisiae hardly assimilates proline during fermentation processes. Our previous studies showed that arginine induces endocytosis of the proline transporter Put4, resulting in inhibition of proline utilization. We here report a possible role of arginine sensing in the inhibition of proline utilization. We first found that two basic amino acids, ornithine, and lysine, inhibit proline utilization by inducing Put4 endocytosis in a manner similar to arginine, but citrulline does not. Our genetic screening revealed that the arginine transporter Can1 is involved in the inhibition of proline utilization by arginine. Intriguingly, the arginine uptake activity of Can1 was not required for the arginine-dependent inhibition of proline utilization, suggesting that Can1 has a function beyond its commonly known function of transporting arginine. More importantly, our biochemical analyses revealed that Can1 activates signaling cascades of protein kinase A in response to extracellular arginine. Hence, we proposed that Can1 regulates proline utilization by functioning as a transceptor possessing the activity of both a transporter and receptor of arginine.

The Cdc25/Ras/cAMP-dependent protein kinase A signaling pathway regulates proline utilization in wine yeast Saccharomyces cerevisiae under a wine fermentation model

Proline is a predominant amino acid in grape must, but it is poorly utilized by the yeast Saccharomyces cerevisiae in wine-making processes. This sometimes leads to a nitrogen deficiency during fermentation and proline accumulation in wine. In this study, we clarified that a glucose response is involved in an inhibitory mechanism of proline utilization in yeast. Our genetic screen showed that strains with a loss-of-function mutation on the CDC25 gene can utilize proline even under fermentation conditions. Cdc25 is a regulator of the glucose response consisting of the Ras/cAMP-dependent protein kinase A (PKA) pathway. Moreover, we found that activation of the Ras/PKA pathway is necessary for the inhibitory mechanism of proline utilization. The present data revealed that crosstalk exists between the carbon and proline metabolisms. Our study could hold promise for the development of wine yeast strains that can efficiently assimilate proline during the fermentation processes.

MNX1-HNF1B Axis Is Indispensable for Intraductal Papillary Mucinous Neoplasm Lineages

BACKGROUND & AIMS

Chromatin architecture governs cell lineages by regulating the specific gene expression; however, its role in the diversity of cancer development remains unknown. Among pancreatic cancers, pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasms (IPMN) with an associated invasive carcinoma (IPMNinv) arise from 2 distinct precursors, and their fundamental differences remain obscure. Here, we aimed to assess the difference of chromatin architecture regulating the transcriptional signatures or biological features in pancreatic cancers.

METHODS

We established 28 human organoids from distinct subtypes of pancreatic tumors, including IPMN, IPMNinv, and PDAC. We performed exome sequencing (seq), RNA-seq, assay for transposase-accessible chromatin-seq, chromatin immunoprecipitation-seq, high-throughput chromosome conformation capture, and phenotypic analyses with short hairpin RNA or clustered regularly interspaced short palindromic repeats interference.

RESULTS

Established organoids successfully reproduced the histology of primary tumors. IPMN and IPMNinv organoids harbored GNAS, RNF43, or KLF4 mutations and showed the distinct expression profiles compared with PDAC. Chromatin accessibility profiles revealed the gain of stomach-specific open regions in IPMN and the pattern of diverse gastrointestinal tissues in IPMNinv. In contrast, PDAC presented an impressive loss of accessible regions compared with normal pancreatic ducts. Transcription factor footprint analysis and functional assays identified that MNX1 and HNF1B were biologically indispensable for IPMN lineages. The upregulation of MNX1 was specifically marked in the human IPMN lineage tissues. The MNX1-HNF1B axis governed a set of genes, including MYC, SOX9, and OLFM4, which are known to be essential for gastrointestinal stem cells. High-throughput chromosome conformation capture analysis suggested the HNF1B target genes to be 3-dimensionally connected in the genome of IPMNinv.

CONCLUSIONS

Our organoid analyses identified the MNX1-HNF1B axis to be biologically significant in IPMN lineages.

Organ-Specific and Mixed Responses to Pembrolizumab in Patients with Unresectable or Metastatic Urothelial Carcinoma: A Multicenter Retrospective Study

To investigate the organ-specific response and clinical outcomes of mixed responses (MRs) to immune checkpoint inhibitors (ICIs) for unresectable or metastatic urothelial carcinoma (ur/mUC), we retrospectively analyzed 136 patients who received pembrolizumab. The total objective response rate (ORR) and organ-specific ORR were determined for each lesion according to the Response Evaluation Criteria in Solid Tumors version 1.1 as follows: (i) complete response (CR), (ii) partial response (PR), (iii) stable disease (SD), and (iv) progressive disease (PD). Most of the organ-specific ORR was 30−40%, but bone metastasis was only 5%. There was a significant difference in overall survival (OS) between responders and non-responders with locally advanced lesions and lymph node, lung, or liver metastases (HR 9.02 (3.63−22.4) p < 0.0001; HR 3.63 (1.97−6.69), p < 0.0001; HR 2.75 (1.35−5.59), p = 0.0053; and HR 3.17 (1.00−10.0), p = 0.049, respectively). MR was defined as occurring when PD happened in one lesion plus either CR or PR occurred in another lesion simultaneously, and 12 cases were applicable. MR was significantly associated with a poorer prognosis than that of the responder group (CR or PR; HR 0.09 (0.02−0.35), p = 0.004). Patients with bone metastases benefitted less. Care may be needed to treat patients with MR as well as patients with pure PD. Further studies should be conducted in the future.

[A Case of Refractory Intermittent Hematuria that Occurred during Paclitaxel/Ramucirumab Combination Therapy for Metastatic Gastric Cancer]

A 76-year-old male patient developed right hydronephrosis due to peritoneal and retroperitoneal dissemination after surgery for gastric cancer. A ureteral stent was inserted, and systemic chemotherapy was introduced for metastatic gastric cancer. Disease progression was observed, and paclitaxel/ramucirumab combination therapy was started as the second-line treatment. After seven courses, severe gross hematuria appeared intermittently, and refractory epistaxis was observed concurrently. No hemorrhagic lesion was found in the imaging test and urethrocystoscopy. The patient received conservative treatment, such as blood transfusion, and further examination was planned. However, hematuria and epistaxis resolved spontaneously during the course of treatment. From the clinical course, it was thought to be a hemorrhagic adverse event due to ramucirumab, and the patient's treatment was therefore changed to another drug. The patient recovered without recurrence of gross hematuria.

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.

Trends in risk classification at diagnosis and choice of primary therapy for prostate cancer: An analysis of 10 839 patients from the Nara Urological Research and Treatment Group registry between 2004 and 2015

OBJECTIVE

To evaluate trends in risk classification at diagnosis and choice of primary therapy in patients diagnosed with prostate cancer.

METHODS

This retrospective study included 10 839 patients who were newly diagnosed with prostate cancer between 2004 and 2015 at 23 Japanese institutions. Risk classification and primary therapies between 2004 and 2015 were evaluated. The trends in risk classification and primary therapy were evaluated using chi-squared tests for trend during four periods (2004-2006; 2007-2009; 2010-2012; and 2013-2015). Binary logistic analysis was used to evaluate the extent to which factors such as age, risk classification, and institution influenced primary therapy choice in the 2013-2015 cohort.

RESULTS

The number of patients with very-low or low-risk classification (P < 0.001) and metastasis (P = 0.04) decreased and the number with intermediate-risk classification (P < 0.001) increased during the four periods. A tendency to choose radical prostatectomy as primary therapy for prostate cancer was not observed during the four periods (P = 0.90). The number of patients who chose radiation therapy (P < 0.001) and active surveillance/watchful waiting (P < 0.001) as primary therapies increased during the four periods and the number of patients who chose androgen deprivation therapy (P < 0.001) decreased. Age, institution, and risk classification significantly influenced primary therapy choice.

CONCLUSIONS

We have shown the trends in risk classification of prostate cancer and primary therapy choices between 2004 and 2015 in Japan. Age, institution, and risk classification significantly influenced the decision on primary therapy for prostate cancer.

Longevity Regulation by Proline Oxidation in Yeast

Proline is a pivotal and multifunctional amino acid that is used not only as a nitrogen source but also as a stress protectant and energy source. Therefore, proline metabolism is known to be important in maintaining cellular homeostasis. Here, we discovered that proline oxidation, catalyzed by the proline oxidase Put1, a mitochondrial flavin-dependent enzyme converting proline into ∆¹-pyrroline-5-carboxylate, controls the chronological lifespan of the yeast Saccharomyces cerevisiae. Intriguingly, the yeast strain with PUT1 deletion showed a reduced chronological lifespan compared with the wild-type strain. The addition of proline to the culture medium significantly increased the longevity of wild-type cells but not that of PUT1-deleted cells. We next found that induction of the transcriptional factor Put3-dependent PUT1 and degradation of proline occur during the aging of yeast cells. Additionally, the lifespan of the PUT3-deleted strain, which is deficient in PUT1 induction, was shorter than that of the wild-type strain. More importantly, the oxidation of proline by Put1 helped maintain the mitochondrial membrane potential and ATP production through the aging period. These results indicate that mitochondrial energy metabolism is maintained through oxidative degradation of proline and that this process is important in regulating the longevity of yeast cells.

Finding long tandem repeats in long noisy reads

Motivation

Long tandem repeat expansions of more than 1000 nt have been suggested to be associated with diseases, but remain largely unexplored in individual human genomes because read lengths have been too short. However, new long-read sequencing technologies can produce single reads of 10 000 nt or more that can span such repeat expansions, although these long reads have high error rates, of 10–20%, which complicates the detection of repetitive elements. Moreover, most traditional algorithms for finding tandem repeats are designed to find short tandem repeats (<1000 nt) and cannot effectively handle the high error rate of long reads in a reasonable amount of time.

Results

Here, we report an efficient algorithm for solving this problem that takes advantage of the length of the repeat. Namely, a long tandem repeat has hundreds or thousands of approximate copies of the repeated unit, so despite the error rate, many short k-mers will be error-free in many copies of the unit. We exploited this characteristic to develop a method for first estimating regions that could contain a tandem repeat, by analyzing the k-mer frequency distributions of fixed-size windows across the target read, followed by an algorithm that assembles the k-mers of a putative region into the consensus repeat unit by greedily traversing a de Bruijn graph. Experimental results indicated that the proposed algorithm largely outperformed Tandem Repeats Finder, a widely used program for finding tandem repeats, in terms of sensitivity.

Availability and implementation

https://github.com/morisUtokyo/mTR.

A new diagnostic indication device of a biomarker growth differentiation factor 15 for mitochondrial diseases: From laboratory to automated inspection

Mitochondrial diseases (MDs) are occasionally difficult to diagnose. Growth differentiation factor 15 (GDF15) has been reported as a biomarker useful for not only diagnosing MDs, but also evaluating disease severity and therapeutic efficacy. To enable the measurement of serum GDF15 concentrations at medical institutions, we developed a new latex-enhanced turbidimetric immunoassay (LTIA) as an automated diagnostic indication test for MDs. We also examined the equivalency of specificity and sensitivity in measuring serum GDF15 concentrations between a commercially available enzyme-linked immunosorbent assay (ELISA) kit and a novel LTIA device in patients with MDs, disease controls, and healthy controls. A clinical performance study used a newly developed LTIA device and an existing ELISA kit to measure the concentrations of GDF15 in 35 MD patients, 111 disease controls, and 86 healthy controls. The median (first quartile-third quartile) of serum GDF15 concentrations measured with the LTIA device was significantly higher (P < .001) in MD patients (1389.0 U/mL [869.5-1776.0 U/mL]) than in healthy controls (380.5 U/mL [330.2-471.8 U/mL]); the interquartile ranges did not overlap between MD patients and healthy controls. The areas under the curve in disease and healthy controls were 0.812 (95% confidence interval [CI]: 0.734-0.886) and 0.951 (95% CI: 0.910-0.992), respectively. The automated, high-throughput technology-based LTIA device has definite advantages over the ELISA kit in shorter processing time and lower estimated cost per sample measurement. The LTIA device of GDF15 may be a sufficiently reliable, frontline, diagnostic indicator of individuals with suspected MDs in the general population.

Appropriate Number of Docetaxel Cycles in Castration-Resistant Prostate Cancer Patients Considering Peripheral Neuropathy and Oncological Control

BACKGROUND

The number of cycles of docetaxel required for castration-resistant prostate cancer (CRPC) is unclear. This study estimated peripheral neuropathy (PN) incidence and the optimal number of treatment cycles in patients receiving docetaxel for CRPC.

PATIENTS AND METHODS

The study retrospectively reviewed 82 patients receiving docetaxel for CRPC at an institution between January 2005 and January 2017. Docetaxel (70 or 75 mg/m2) was administered every 3 weeks, and prednisone 5 mg or dexamethasone 0.5 mg was administered twice a day.

RESULTS

PN (grade ≥2) was noted in 32 (39.0%) patients. The median cumulative dose of docetaxel associated with PN was 675 mg/m2. No factor significantly predicted the occurrence of PN. The prostate-specific antigen progression rate, prostate cancer-specific survival, and overall survival were significantly better with ≥8 cycles of docetaxel than with <8 cycles (p < 0.05).

CONCLUSION

The incidence of PN is high, and 8 treatment cycles are optimal for patients receiving docetaxel for CRPC.

Triglyceride to HDL-cholesterol ratio is a predictor of future coronary events: a possible role of high-risk coronary plaques detected by coronary CT angiography

Background

For the prevention of future cardiovascular events, control of residual risks such as triglyceride rich lipoproteins and HDL-cholesterol is an emerging problem beyond LDL-cholesterol. Triglyceride to HDL-cholesterol ratio (TG/HDL ratio) has been reported to be useful for risk classification of cardiovascular diseases. Meanwhile, several studies showed that high-risk plaque characteristics evaluated with coronary CT angiography (cCTA) was associated with the incidence of acute coronary syndrome. However, the relationship of TG/HDL ratio with coronary plaque characteristics and its impact of this association on future coronary events have not been fully elucidated.

Purpose

The aim of this study was to evaluate the association between TG/HDL ratio and high-risk plaque detected by cCTA and its impact on future coronary events.

Methods

A total of 944 patients suspected stable coronary artery disease who underwent cCTA at our institution were analyzed (mean 64-year-old, 55% male). Patients were divided into two groups by the median value of TG/HDL ratio (higher TG/HDL: TG/HDL ratio ≥2.0, lower TG/HDL: TG/HDL ratio &lt;2.0). Coronary high-risk plaques were defined as a plaque with all three components; low attenuation plaque (&lt;50H.U.), positive remodeling (remodeling index &gt;1.1) and spotty calcification. Cardiovascular event was defined as cardiovascular death, acute coronary syndrome, and late coronary revascularization after 30 days of CT acquisition.

Results

The higher TG/HDL ratio was significantly associated with male gender (63% vs. 48%, P&lt;0.001), body mass index (24.8±3.8 vs. 22.9±4.0, p&lt;0.001), the prevalence of hypertension (65% vs. 54%, P&lt;0.001), dyslipidemia (60% vs. 42%, P&lt;0.001), diabetes mellitus (38% vs. 27%, P=0.001) and current smoking (26% vs. 10%, p&lt;0.001). Regarding cCTA findings, the prevalence of significant stenosis, calcified plaque, non-calcified plaque, coronary plaques with low attenuation plaque, positive remodeling and spotty calcification in the higher TG/HDL group were greater than those in the lower group (Figure 1A). Of note, the difference in high-risk plaque between two groups was significant. (18% vs. 11%, p=0.004). Multivariate logistic analysis revealed that the TG/HDL ratio was an independent risk factor for high-risk plaque even after adjustment (OR, 1.35; 95% CI, 1.01–1.81; p=0.049). Regarding coronary events (median follow-up duration; 48 months), Kaplan-Meier curve showed poor event-free rate in the higher TG/HDL group (Figure 1B). At Cox proportional hazard analysis, higher TG/HDL ratio (HR, 1.94; 95% CI, 1.01–3.70; p=0.046) and CT-verified high-risk plaque (HR, 2.36; 95% CI, 1.27–4.38; p=0.006) were independent predictive factors for coronary events even after adjustment.

Conclusion

TG/HDL ratio is involved in the vulnerability of CT-verified coronary plaque characteristics. This association may play an important role in the prognostic impact of TG/HDL ratio on future cardiovascular events.

Funding Acknowledgement

Type of funding source: None

Clinical Impact of Sarcopenia and Inflammatory/Nutritional Markers in Patients with Unresectable Metastatic Urothelial Carcinoma Treated with Pembrolizumab

Sarcopenia is a muscle loss syndrome known as a risk factor of various carcinomas. The impact of sarcopenia and sarcopenia-related inflammatory/nutritional markers in metastatic urothelial carcinoma (mUC) treated with pembrolizumab was unknown, so this retrospective study of 27 patients was performed. Psoas muscle mass index (PMI) was calculated by bilateral psoas major muscle area at the L3 with computed tomography. The cut-off PMI value for sarcopenia was defined as ≤6.36 cm²/m² for men and ≤3.92 cm²/m² for women. Neutrophil-to-lymphocyte ratio (NLR) ≥ 4.0 and sarcopenia correlated with significantly shorter progression-free survival (PFS) (hazard ratio (HR) 3.81, p = 0.020; and HR 2.99, p = 0.027, respectively). Multivariate analyses identified NLR ≥ 4.0 and sarcopenia as independent predictors for PFS (HR 2.89, p = 0.025; and HR 2.79, p = 0.030, respectively). Prognostic nutrition index < 45, NLR ≥ 4.0 and sarcopenia were correlated with significantly worse for overall survival (OS) (HR 3.44, p = 0.046; HR 4.26, p = 0.024; and HR 3.92, p = 0.012, respectively). Multivariate analyses identified sarcopenia as an independent predictor for OS (HR 4.00, p = 0.026). Furthermore, a decrease in PMI ≥ 5% in a month was an independent predictor of PFS and OS (HR 12.8, p = 0.008; and HR 6.21, p = 0.036, respectively). Evaluation of sarcopenia and inflammatory/nutritional markers may help in the management of mUC with pembrolizumab.

Unexpected presentation and surgical salvage of transplant renal artery dissection caused by vascular clamping: a case report

Background

Transplant renal artery dissection is a rare and serious event that can cause allograft dysfunction and activation of the renin–mediated renovascular hypertension. Most cases are induced by percutaneous transluminal angioplasty, arteriosclerotic disease, or fibromuscular dysplasia. We observed a case of transplant renal artery dissection induced by unusual causes during kidney transplantation.

Case presentation

A 35-year-old woman, whose mother donated a kidney to her, underwent ABO-incompatible living kidney transplantation. The allograft had one renal artery and vein that were anastomosed to the internal iliac artery and external iliac vein, respectively. Although careful handling was performed in all procedures including vascular clamping, Doppler ultrasonography (US) immediately after reperfusion showed an increase in the systolic blood velocity and urine output was not observed. Arterial anastomotic stenosis was suspected, but upon exploration, a renal artery dissection was detected in the middle portion of the donor artery. The part of the transplant renal artery was resected, and cold reflux was started again. At the resected part of transplant renal artery, dissection was identified. After re-anastomosis, Doppler US revealed that the blood flow of the renal artery was adequate without an increase in the systolic blood velocity, and sufficient blood flow was observed throughout the allograft. Urine output was also observed as soon as blood flow returned, and serum creatinine level decreased to 0.95 mg/dL after surgery. The cause of injury might have been vascular clamping in order to drain the air and check bleeding at the anastomosis.

Conclusions

Our case reaffirmed that careful handling is needed in all procedures, including donor nephrectomy, cannulation for transplant perfusion, vascular clamping, and anastomosis, even without any evidence of arteriosclerosis. Kidney transplant recipients commonly have atherosclerosis and hypertension, which are risk factors for arterial dissection. Early diagnosis and intervention can lead to the prevention of allograft dysfunction. Therefore, close monitoring of allograft blood flow by Doppler US during surgery should be considered.

Determination of contrast medium dose for hepatic CT enhancement with improved body size dependency using a non-linear analysis based on pharmacokinetic principles

AIM

To propose a pharmacokinetic non-linear analysis method to determine contrast medium (CM) dose for computed tomography (CT) hepatic enhancement to improve body size dependency and validate the proposed CM dose determination method through a clinical study.

MATERIALS AND METHODS

Enhancement data of 105 patients who underwent hepatic dynamic CT with a fixed CM dose were analysed. From the analysis results, CM doses as a function of each of four body size indices (body weight [BW], lean body weight [LBW], blood volume [BV], and body surface area [BSA]) for achieving improved body size dependency were determined (proposed method), and the body size dependencies were simulated using the enhancement data from 105 patients. The proposed method was validated with a two-arm clinical study on BW. Body size dependency was evaluated using p-value of correlation coefficient between Body size indices and enhancements (p<0.05: significant dependency) and mean absolute error (MAE).

RESULTS

The simulation showed that significant body size dependencies not considered by the conventional method can be improved by the proposed method. MAEs of BW, LBW, and BV were also significantly reduced (p<0.05). The clinical study with BW demonstrated a similar improvement to that in the simulation result. MAE was also significantly reduced (p<0.001).

CONCLUSION

The proposed method demonstrated more improved BW, LBW, and BV dependence compared to the conventional method. Through the two-arm clinical study, the proposed method using BW only, without height information, is a suitable index for improving body size dependency.

P3632Prognostic impact of aortic valve stenosis in patients with acute myocardial infarction

Background

Aortic valve stenosis (AS) is associated with the presence and severity of coronary artery disease independently of clinical risk factors, which leads to increased cardiovascular mortality. However, the prevalence of AS and its prognostic value among patients with acute myocardial infarction (AMI) remain unknown.

Purpose

The purpose of this study was to investigate the prevalence and prognostic impact of AS in AMI patients.

Methods

We studied 2,803 AMI patients using data from Mie ACS registry, a prospective and multicenter registry. Patients were divided into subgroups according to the presence and severity of AS based on maximal aortic flow rate by Doppler echocardiography before hospital discharge: non-AS <2.0 m/s, 2.0 m/s≤mild AS <3.0 m/s, 3.0 m/s≤moderate AS <4.0m/s and severe AS≥4.0 m/s. The primary outcome was defined as 2-year all-cause mortality.

Results

AS was detected in 79 patients (2.8%) including 49 mild AS, 23 moderate AS and 6 severe AS. AS patients were significantly older (79.9±9.8 versus 68.3±12.6 years), and higher killip classification than non-AS patients (P<0.01, respectively). However, left ventricular ejection fraction, and prevalence of primary PCI was similar between the 2 groups. During the follow-up periods (median 725 days), 333 (11.9%) patients experienced all-cause death. AS patients demonstrated the higher all-cause mortality rate compared to that of non-AS patients during follow up (47.3% versus 11.3%, P<0.0001, chi square). Kaplan-Meier curves showed that the probability of all-cause mortality was significantly higher among AS patients than non-AS patients, and was highest among moderate and severe AS (See figure A and B). Cox regression analyses for all-cause mortality demonstrated that the severity of AS was the strongest and independent poor prognostic factor (HR 1.71, 95% CI 1.30–2.24, P<0.001, See table).

Cox hazard regression analysis Hazard ratio 95% Confidential interval P-value Severity of aortic valve stenosis 1.71 1.30–2.24 <0.001 Killip classification 1.63 1.46–1.82 <0.001 Age 1.07 1.06–1.09 <0.001 Serum creatinine level 1.05 1.03–1.08 <0.001 Max CPK level 1.00 1.00–1.01 <0.001 Left ventricular ejection fraction 0.96 0.95–0.97 <0.001 Primary percutaneous coronary intervention 0.67 0.47–0.96 0.03 CPK suggests creatinine phosphokinase.

All cause mortality

Conclusions

The presence of AS of any severity contributes to worsening of patients' prognosis following AMI independently of other known risk factors.

Acknowledgement/Funding

None

P1956Geriatric nutritional risk index as predictor for long-term survival and cardiovascular or limb events in peripheral arterial disease patients

Background

The geriatric nutritional risk index (GNRI) is a simple tool to assess the nutritional risk and associated with mortality. However, there are no reports focusing GNRI in peripheral artery disease (PAD) patients.

Purpose

The purpose of this study was to examine the effects of GNRI for long-term survival, cardiovascular and limb events in PAD patients.

Methods

A prospective cohort study was performed in 1219 PAD patients. Baseline GNRI was calculated from serum albumin level and body-mass-index. The patients were divided into four groups by GNRI level (G1: >98; G2: 92–98; G3: 82–91; G4: <82). The endpoints were overall survival (OS) and freedom from major adverse cardiovascular and limb events (MACE and MACLE).

Results

The median follow-up was 73 months. There were 626 deaths (51.4%) during follow-up. The rate of cardiovascular death among dead was 51.3%. The OS rates markedly depended on GNRI level (p<0.01). The 5-year OS rates were G1: 80.8%, G2: 62.0%, G3: 40.0%, G4: 23.3%, respectively. In multivariate analyses, GNRI, age, low ankle brachial pressure index (ABI), low estimated glomerular filtration rate (eGFR), and high C-reactive protein (CRP) levels were independent factors associated with OS (<0.05). GNRI, age, low ABI, diabetes mellitus, coronary artery disease, lower eGFR and higher CRP levels were associated with MACE and MACLE (p<0.05, respectively). Besides, statins improved OS, MACE, and MACLE (<0.01, respectively).

Conclusions

GNRI was an independent predictor for OS, MACE, and MACLE in PAD patients. Furthermore,statins improved OS, MACE and MACLE in patients with PAD.

P692Chemoradiation therapy to patients with lung cancer exacerbates thoracic aortic calcification

Introduction

Development of chemoradiation therapy (CRT) has improved mortality in patients with cancer. Whereas, it is emerging problem that cancer-survivors suffer from cardiovascular diseases, and the association between modern CRT and the increase in future cardiovascular events is suggested. Meanwhile, previous studies showed that thoracic aortic calcification (TAC) detected by computed tomography (CT), a marker of atherosclerosis, was associated with all-cause mortality and cardiovascular events. However, the influence of CRT on TAC progression remains unclear.

Purpose

The purpose of this study was to evaluate whether CRT would exacerbate TAC.

Methods

A total of 68 patients who treated lung cancer at our hospital between 2011 and 2015 were retrospectively analyzed (mean 62 year-old, male 78%): 35 patients underwent surgical treatment after induction CRT (CRT group) and 33 patients underwent surgical treatment alone (control group), extracted by propensity score matching by age, sex, smoking status, and diseased side. The volume of TAC between 2nd and 12th thoracic vertebrae was quantitatively measured with CT imaging, at baseline and at 1 year follow-up. The annual percent change in TAC was compared between the CRT and the control group. Moreover, the independent relationship between implementation of CRT and the progression of TAC was assessed by multivariate logistic regression analysis, adjusting for age, gender, conventional atherosclerotic risk factors and baseline aortic calcification volume.

Results

Patients in the CRT group received radiation (mean 47.3±4.0 Gy) and chemotherapy: 2 courses of cisplatin with docetaxel (34 cases) or vinorelbine (1 case). The prevalence of dyslipidemia, taking statins and diabetes drugs were significantly higher in the control groups (17% vs. 39%; p=0.041, 11% vs. 33%; p=0.029, 3% vs. 18%; p=0.044, respectively). Baseline C-reactive protein level was significantly higher in the CRT group (0.255 vs. 0.115; p=0.034). In univariate analysis, the annual percent change in TAC volume was significantly increased in the CRT group compared with the control group (37.6% vs. 23.3%; p=0.006). Multivariate logistic regression analysis demonstrated that CRT was an independent factor associated with the progression of TAC volume, even after adjustment for baseline calcification volume and coronary risk factors (OR, 3.90; 95% CI, 1.32–11.47; p=0.014).

Conclusion

CRT to patients with lung cancer exacerbates thoracic aortic calcification, which may result in future cardiovascular events.

Clinical Significance of Postoperative Nutritional Status as a Prognostic Factor in Kidney Transplant Recipients

BACKGROUND

Despite advancements in the management of kidney transplantation (KT), kidney transplant recipients (KTRs) have a higher risk of mortality than the age-matched general population. Improvement of long-term graft and patient survival is a significant issue. Therefore we investigated the effects of postoperative nutritional status on graft and patient survival and explored the predictive factors involved in nutritional status.

METHODS

Our retrospective study included 118 KTRs who underwent KT at our hospital. Clinical and laboratory data were obtained from medical charts. The prognostic nutritional index (PNI) was used to assess nutritional status. Changes in nutritional status after KT were monitored and the effect of nutritional status on graft and patient survival was investigated. The variables involved in nutritional status were also explored.

RESULTS

The KTRs in this cohort comprised 66 men and 52 women with a median age of 47 years at KT. There were 16, 32, and 22 cases of cadaveric, preemptive, and ABO-incompatible KTs, respectively. Postoperative PNI gradually improved and was stable from 6 months after KT. Although graft survival was regulated by ABO-compatibility, independent predictors for patient survival were history of dialysis, PNI, and serum-corrected calcium levels. Preemptive KT and inflammatory status contributed to PNI.

CONCLUSIONS

Nutritional status of KTRs improved over time after KT and could contribute to patient survival. Optimal nutritional educational programs and interventions can lead to better outcomes in KTRs. Further studies are needed to validate our results and develop appropriate nutritional educational programs, interventions, and exercise programs.

Recompleting the Caenorhabditis elegans genome

Caenorhabditis elegans was the first multicellular eukaryotic genome sequenced to apparent completion. Although this assembly employed a standard C. elegans strain (N2), it used sequence data from several laboratories, with DNA propagated in bacteria and yeast. Thus, the N2 assembly has many differences from any C. elegans available today. To provide a more accurate C. elegans genome, we performed long-read assembly of VC2010, a modern strain derived from N2. Our VC2010 assembly has 99.98% identity to N2 but with an additional 1.8 Mb including tandem repeat expansions and genome duplications. For 116 structural discrepancies between N2 and VC2010, 97 structures matching VC2010 (84%) were also found in two outgroup strains, implying deficiencies in N2. Over 98% of N2 genes encoded unchanged products in VC2010; moreover, we predicted ≥53 new genes in VC2010. The recompleted genome of C. elegans should be a valuable resource for genetics, genomics, and systems biology.

Successful salvage of allograft dysfunction triggered by transplant renal vein thrombosis immediately after kidney transplantation: a case report

Background

Transplant renal vein thrombosis (TRVT) is a severe vascular complication and is caused by various factors, including recipient factors, donor factors, immunosuppression regimens, and surgical techniques. Despite adequate interventions, including thrombolytic therapy or surgical thrombectomy, successful salvage of the allograft is often difficult. We observed a case of TRVT induced by compression of the renal vein immediately after intraoperative abdominal closure.

Case presentation

A 41-year-old male underwent ABO-compatible living kidney transplantation. The donor was his 45-year-old sister, and her right kidney was donated. The allograft had a single artery and vein. One of the preoperative recipient problems was obesity (body mass index, 33.4 kg/m²). Intraoperative Doppler ultrasonography (US) revealed sufficient blood flow throughout the allograft, and urine output was also observed. After surgery, hematuria was observed; the urine output decreased and serum creatinine levels increased to 7.0 mg/dL. Doppler US showed a decrease in diastolic flow and an elevated resistive index, which were similar findings to those noted in acute rejection. Although steroid pulse therapy was initiated, allograft dysfunction was worsening. On postoperative day 4, surgical exploration revealed TRVT; consequently, thrombectomy was performed. The urine output increased, and serum creatinine levels decreased to 1.8 mg/dL. The cause of TRVT development may be that the transplant renal vein was relatively short, due to the right kidney being compressed by surrounding tissues after abdominal closure, and that TRVT was gradually developing due to stagnant blood flow.

Conclusion

Although TRVT is induced by multiple factors, an accurate diagnosis is often difficult. Understanding these factors, including obesity, and considering TRVT as a cause of allograft dysfunction are important during the pre-, peri-, and postoperative periods. Knowledge of TRVT can lead to early and accurate diagnosis and intervention, resulting in better outcomes for the patients with allograft dysfunction.

Plasma Collection Using Nafamostat Mesilate and Dipyridamole as an Anticoagulant

Nafamostat mesilate (FUT-175) is a strong protease inhibitor and is used as an anticoagulant in extracorporeal circulation. In the present study, we administered FUT and dipyridamole as anticoagulants during donor plasmapheresis, and the additional effect of dipyridamole was examined. In dogs weighing about 15 Kg, donor plasmapheresis was performed using a cellulose triacetate membrane plasmaseparator (PEX-15, Nipro), and 300 ml of filtrated plasma was obtained within 30 minutes. These dogs were divided into two groups, 50 mg/h of FUT alone was infused (group A, n=10), and the same dose of FUT and 25 mg/h of dipyridamole were infused (group B, n=5) during plasmapheresis. Changes of the coagulation system, blood cell counts and complement system were investigated. In clinical cases, an artificial liver support therapy using FUT as an anticoagulant was performed on 8 patients with acute liver failure, and blood compatibility was examined.

In dogs, RBC counts and hematocrits were almost stable, but WBC counts were decreased to about 70% of the previous value. Platelets counts were about 60% and 80% of the previous value, in group A and group B, respectively, at the end of the plasmapheresis (P<0.01). Clotting factor VIII was diminished to about 20% and 35% of the previous value in group A and B, respectively. In clinical cases, all patients received the plasma exchange combined with hemodialysis using FUT as an anticoagulant, and no distinct side effect was observed during plasma exchange.

Spectroscopy of Pionic Atoms in ^{122}Sn(d,^{3}He) Reaction and Angular Dependence of the Formation Cross Sections

We observed the atomic 1s and 2p states of π^{-} bound to ^{121}Sn nuclei as distinct peak structures in the missing mass spectra of the ^{122}Sn(d,^{3}He) nuclear reaction. A very intense deuteron beam and a spectrometer with a large angular acceptance let us achieve a potential of discovery, which includes the capability of determining the angle-dependent cross sections with high statistics. The 2p state in a Sn nucleus was observed for the first time. The binding energies and widths of the pionic states are determined and found to be consistent with previous experimental results of other Sn isotopes. The spectrum is measured at finite reaction angles for the first time. The formation cross sections at the reaction angles between 0° and 2° are determined. The observed reaction-angle dependence of each state is reproduced by theoretical calculations. However, the quantitative comparison with our high-precision data reveals a significant discrepancy between the measured and calculated formation cross sections of the pionic 1s state.

A Framework Supporting the Development of a Grid Portal for Analysis Based on ROI

Objectives: In our research on brain function analysis, users require two different simultaneous types of processing: interactive processing to a specific part of data and high-performance batch processing to an entire dataset. The difference between these two types of processing is in whether or not the analysis is for data in the region of interest (ROI). In this study, we propose a Grid portal that has a mechanism to freely assign computing resources to the users on a Grid environment according to the users’ two different types of processing requirements.

Methods: We constructed a Grid portal which integrates interactive processing and batch processing by the following two mechanisms. First, a job steering mechanism controls job execution based on user-tagged priority among organizations with heterogeneous computing resources. Interactive jobs are processed in preference to batch jobs by this mechanism. Second, a priority-based result delivery mechanism that administrates a rank of data significance.

Results: The portal ensures a turn-around time of interactive processing by the priority-based job controlling mechanism, and provides the users with quality of services (QoS) for interactive processing. The users can access the analysis results of interactive jobs in preference to the analysis results of batch jobs. The Grid portal has also achieved high-performance computation of MEG analysis with batch processing on the Grid environment.

Conclusion: The priority-based job controlling mechanism has been realized to freely assign computing resources to the users’ requirements. Furthermore the achievement of high-performance computation contributes greatly to the overall progress of brain science. The portal has thus made it possible for the users to flexibly include the large computational power in what they want to analyze.

Centromere evolution and CpG methylation during vertebrate speciation

Centromeres and large-scale structural variants evolve and contribute to genome diversity during vertebrate speciation. Here, we perform de novo long-read genome assembly of three inbred medaka strains that are derived from geographically isolated subpopulations and undergo speciation. Using single-molecule real-time (SMRT) sequencing, we obtain three chromosome-mapped genomes of length ~734, ~678, and ~744Mbp with a resource of twenty-two centromeric regions of length 20-345kbp. Centromeres are positionally conserved among the three strains and even between four pairs of chromosomes that were duplicated by the teleost-specific whole-genome duplication 320-350 million years ago. The centromeres do not all evolve at a similar pace; rather, centromeric monomers in non-acrocentric chromosomes evolve significantly faster than those in acrocentric chromosomes. Using methylation sensitive SMRT reads, we uncover centromeres are mostly hypermethylated but have hypomethylated sub-regions that acquire unique sequence compositions independently. These findings reveal the potential of non-acrocentric centromere evolution to contribute to speciation.

Anti-β2-glycoprotein I antibodies

The relationship between presence of anti-β2-glycoprotein I autoantibodies (aβ2-GPI) and history of thrombosis is now widely known. However, differences in the methodology of aβ2-GPI detection have made the comparison of data from different laboratories extremely difficult. We discuss the significance of aβ2-GPI of the IgG, IgM and IgA isotypes, and our approach to developing an easier and more reproducible method for the detection of this autoantibody. In addition, we present data that shows that commercially available enzyme immunoassay plates differ regarding detectability of aβ2-GPI. Since the clinical significance of this heterogeneity is presently unclear, the set-up of the detection systems and interpretation of data need great care.

Human monoclonal antibodies against the complex of phosphatidylserine and prothrombin from patients with the antiphospholipid antibodies

The presence of antibodies against the complex of prothrombin and phosphatidylserine (aPS/PT) more significantly correlates with manifestations of antiphospholipid syndrome (APS) and with the presence of lupus anticoagulants (LA) than antibodies against prothrombin bound to oxygenated polystyrene (aPT-A). To investigate immunological specificities and functional activities of aPS/PT, four monoclonal aPS/PT, designated as HG-4, KE-6, KF-5 and KF-6, from two patients with antiphospholipid antibodies (aPL) were established and characterized. Three of these antibodies (HG-4, KF-5 and KF-6) recognized the complex of phosphatidylserine and prothrombin, but did not react to prothrombin directly coated on oxygenated plates. KE-6 bound not only to the complex of phosphatidylserine and prothrombin but also to prothrombin on oxygenated plates. None of them showed the binding activity to prothrombin directly coated on non-oxygenated plates. HG-4, KE-6 and KF-5 had LA-like activity. The findings support the hypothesis that autoimmune aPS/PT recognize the cryptic epitopes or neoepitopes exposed upon interaction between prothrombin and phosphatidylserine, and that aPS/PT are, at least in part, responsible for LA activity. Lupus (2007) 16, 509—516.

MR Imaging of Hippocampal Sulcus Remnant: Age-Related Differences

The hippocampal sulcus remnant (HSR) is often observed at the medial temporal lobe on MR images. In the present study, we made a retrospective assessment of the frequency and age-related differences in HSR in routine brain MR examinations of 1000 patients, 494 females and 506 males. Cases with one or several spots that were hypointense on T1-weighted and FLAIR images and hyperintense on T2-weighted images were defined as positive for HSR. Abnormal spots with the same intensity as cerebrospinal fluid were observed in 210 out of 506 males and in 193 out of 494 females. No significant sex-related differences were observed in the frequency of HSR. The HSR was seen more frequently with age in both males and females. Patients with hypertension had a significantly higher frequency of HSR.

AgIn: measuring the landscape of CpG methylation of individual repetitive elements

Motivation: Determining the methylation state of regions with high copy numbers is challenging for second-generation sequencing, because the read length is insufficient to map reads uniquely, especially when repetitive regions are long and nearly identical to each other. Single-molecule real-time (SMRT) sequencing is a promising method for observing such regions, because it is not vulnerable to GC bias, it produces long read lengths, and its kinetic information is sensitive to DNA modifications.

Results: We propose a novel linear-time algorithm that combines the kinetic information for neighboring CpG sites and increases the confidence in identifying the methylation states of those sites. Using a practical read coverage of ∼30-fold from an inbred strain medaka (Oryzias latipes), we observed that both the sensitivity and precision of our method on individual CpG sites were ∼93.7%. We also observed a high correlation coefficient (R = 0.884) between our method and bisulfite sequencing, and for 92.0% of CpG sites, methylation levels ranging over [0,1] were in concordance within an acceptable difference 0.25. Using this method, we characterized the landscape of the methylation status of repetitive elements, such as LINEs, in the human genome, thereby revealing the strong correlation between CpG density and hypomethylation and detecting hypomethylation hot spots of LTRs and LINEs. We uncovered the methylation states for nearly identical active transposons, two novel LINE insertions of identity ∼99% and length 6050 base pairs (bp) in the human genome, and 16 Tol2 elements of identity >99.8% and length 4682 bp in the medaka genome.

Availability and Implementation: AgIn (Aggregate on Intervals) is available at: https://github.com/hacone/AgIn

Contact:ysuzuki@cb.k.u-tokyo.ac.jp or moris@cb.k.u-tokyo.ac.jp

Supplementary information:Supplementary data are available at Bioinformatics online.

A linear time algorithm for detecting long genomic regions enriched with a specific combination of epigenetic states

Background

Epigenetic modifications are essential for controlling gene expression. Recent studies have shown that not only single epigenetic modifications but also combinations of multiple epigenetic modifications play vital roles in gene regulation. A striking example is the long hypomethylated regions enriched with modified H3K27me3 (called, "K27HMD" regions), which are exposed to suppress the expression of key developmental genes relevant to cellular development and differentiation during embryonic stages in vertebrates. It is thus a biologically important issue to develop an effective optimization algorithm for detecting long DNA regions (e.g., >4 kbp in size) that harbor a specific combination of epigenetic modifications (e.g., K27HMD regions). However, to date, optimization algorithms for these purposes have received little attention, and available methods are still heuristic and ad hoc.

Results

In this paper, we propose a linear time algorithm for calculating a set of non-overlapping regions that maximizes the sum of similarities between the vector of focal epigenetic states and the vectors of raw epigenetic states at DNA positions in the set of regions. The average elapsed time to process the epigenetic data of any of human chromosomes was less than 2 seconds on an Intel Xeon CPU. To demonstrate the effectiveness of the algorithm, we estimated large K27HMD regions in the medaka and human genomes using our method, ChromHMM, and a heuristic method.

Conclusions

We confirmed that the advantages of our method over those of the two other methods. Our method is flexible enough to handle other types of epigenetic combinations. The program that implements the method is called "CSMinfinder" and is made available at: http://mlab.cb.k.u-tokyo.ac.jp/~ichikawa/Segmentation/

[Diffusion studies of redox-sensitive nitroxyl spin probes through bilayer lipid membranes using 300 MHz electron spin resonance spectrometer]

Electron spin resonance (ESR) studies were carried out for 14N-labeled deuterated 3-methoxy-carbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (MC-PROXYL) and 3-carboxy-2,2,5,5-tetramethyl-1-pyrrolidin-1-oxyl (carboxy-PROXYL) in pure water and various concentrations of liposomal solutions by using 300 MHz ESR spectrometer. The ESR parameters such as the line width, hyperfine coupling constant, rotational correlation time, g-factor, partition parameter and permeability were reported for the samples. The line width broadening was observed for MC-PROXYL and carboxy-PROXYL in liposomal solution. The hyperfine coupling constant was observed for both nitroxyl spin probes. The permeable and impermeable nature of nitroxyl spin probes was demonstrated. The rotational correlation time increases with increasing concentration of liposome. The partition parameter increases with increasing concentration of liposome for MC-PROXYL, which indicates that the nitroxyl spin probes diffuse into lipid membrane. The permeability value decreases with increasing concentration of liposome, which reveals an increase in membrane permeability. The peaks corresponding to the lipid phase were observed for MC-PROXYL in liposomal solution, but not resolved for carboxy-PROXYL. These results confirm the permeable and impermeable nature of nitroxyl spin probes.