Comparison of the electrophysiological properties of the pulmonary veins between paroxysmal and persistent atrial fibrillation

Background

The role of the pulmonary veins (PVs) as triggers in atrial fibrillation (AF) is well-known; however, their detailed electrophysiological properties have not been thoroughly examined.

Objective

This study aimed to investigate the electrophysiological properties of the PVs between paroxysmal AF (pAF) and persistent AF (perAF).

Methods

Prior to catheter ablation in patients with pAF (n = 51) and perAF (n = 41), a voltage map of the left atrium and PVs was created under sinus rhythm, and the area of the myocardial sleeves in the PVs and their electrophysiological characteristics, including the pacing threshold and effective refractory period (ERP), were compared between the two groups.

Results

Compared with perAF, the myocardial sleeves of PVs for pAF were significantly larger for all PVs. The ERP for perAF was significantly shorter than that for pAF for all PVs. The pacing threshold for perAF was significantly higher than that for pAF for the right and left superior PVs.

Conclusion

In patients with perAF, a decrease in the normal myocardial sleeves and a shortening of the ERP were observed for all PVs. Those changes in the electrophysiological properties of the PVs might be related to the persistence of AF.

A multi-institutional, observational study of outcomes after catheter placement for peritoneal dialysis in Japan

BACKGROUND

This multi-institutional, observational study examined whether the outcomes after peritoneal dialysis (PD) catheter placement in Japan meet the audit criteria of the International Society for Peritoneal Dialysis (ISPD) guideline and identified factors affecting technique survival and perioperative complications.

METHODS

Adult patients who underwent first PD catheter placement for end-stage kidney disease between April 2019 and March 2021 were followed until PD withdrawal, kidney transplantation, transfer to other facilities, death, 1 year after PD start or March 2022, whichever came first. Primary outcomes were time to catheter patency failure and technique failure, and perioperative infectious complications within 30 days of catheter placement. Secondary outcomes were perioperative complications. Appropriate statistical analyses were performed to identify factors associated with the outcomes of interest.

RESULTS

Of the total 409 patients, 8 who underwent the embedded catheter technique did not have externalised catheters. Of the 401 remaining patients, catheter patency failure occurred in 25 (6.2%). Technical failure at 12 months after PD catheter placement calculated from cumulative incidence function was 15.3%. On Cox proportional hazards model analysis, serum albumin (hazard ratio (HR) 0.44; 95% confidence interval (CI) 0.27-0.70) and straight type catheter (HR 2.14; 95% CI 1.24-3.69) were the independent risk factors for technique failure. On logistic regression analysis, diabetes mellitus was the only independent risk factor for perioperative infectious complications (odds ratio 2.70, 95% CI 1.30-5.58). The occurrence rate of perioperative complications generally met the audit criteria of the ISPD guidelines.

CONCLUSION

PD catheter placement in Japan was proven to be safe and appropriate.

Oral Iron Absorption of Ferric Citrate Hydrate and Hepcidin-25 in Hemodialysis Patients: A Prospective, Multicenter, Observational Riona-Oral Iron Absorption Trial

Oral ferric citrate hydrate (FCH) is effective for iron deficiencies in hemodialysis patients; however, how iron balance in the body affects iron absorption in the intestinal tract remains unclear. This prospective observational study (Riona-Oral Iron Absorption Trial, R-OIAT, UMIN 000031406) was conducted at 42 hemodialysis centers in Japan, wherein 268 hemodialysis patients without inflammation were enrolled and treated with a fixed amount of FCH for 6 months. We assessed the predictive value of hepcidin-25 for iron absorption and iron shift between ferritin (FTN) and red blood cells (RBCs) following FCH therapy. Serum iron changes at 2 h (ΔFe2h) after FCH ingestion were evaluated as iron absorption. The primary outcome was the quantitative delineation of iron variables with respect to ΔFe2h, and the secondary outcome was the description of the predictors of the body's iron balance. Generalized estimating equations (GEEs) were used to identify the determinants of iron absorption during each phase of FCH treatment. ΔFe2h increased when hepcidin-25 and TSAT decreased (-0.459, -0.643 to -0.276, p = 0.000; -0.648, -1.099 to -0.197, p = 0.005, respectively) in GEEs. FTN increased when RBCs decreased (-1.392, -1.749 to -1.035, p = 0.000) and hepcidin-25 increased (0.297, 0.239 to 0.355, p = 0.000). Limiting erythropoiesis to maintain hemoglobin levels induces RBC reduction in hemodialysis patients, resulting in increased hepcidin-25 and FTN levels. Hepcidin-25 production may prompt an iron shift from RBC iron to FTN iron, inhibiting iron absorption even with continued FCH intake.

Focal segmental glomerulosclerosis with a mutation in the mitochondrially encoded NADH dehydrogenase 5 gene: A case report

NADH dehydrogenase 5 (ND5) is one of 44 subunits composed of Complex I in mitochondrial respiratory chain. Therefore, a mitochondrially encoded ND5 (MT-ND5) gene mutation causes mitochondrial oxidative phosphorylation (OXPHOS) disorder, resulting in the development of mitochondrial diseases. Focal segmental glomerulosclerosis (FSGS) which had podocytes filled with abnormal mitochondria is induced by mitochondrial diseases. An MT-ND5 mutation also causes FSGS. We herein report a Japanese woman who was found to have proteinuria and renal dysfunction in an annual health check-up at 29 years old. Because her proteinuria and renal dysfunction were persistent, she had a kidney biopsy at 33 years of age. The renal histology showed FSGS with podocytes filled with abnormal mitochondria. The podocytes also had foot process effacement and cytoplasmic vacuolization. In addition, the renal pathological findings showed granular swollen epithelial cells (GSECs) in tubular cells, age-inappropriately disarranged and irregularly sized vascular smooth muscle cells (AiDIVs), and red-coloured podocytes (ReCPos) by acidic dye. A genetic analysis using peripheral mononuclear blood cells and urine sediment cells detected the m.13513 G > A variant in the MT-ND5 gene. Therefore, this patient was diagnosed with FSGS due to an MT-ND5 gene mutation. Although this is not the first case report to show that an MT-ND5 gene mutation causes FSGS, this is the first to demonstrate podocyte injuries accompanied with accumulation of abnormal mitochondria in the cytoplasm.

Two cases of aseptic internal jugular vein thrombophlebitis associated with hemodialysis catheter, presenting as sore throat: case report and literature review

Background

Non-cuffed hemodialysis (HD) catheters are often used for emergency or temporary vascular access. Its complications include thrombosis and catheter-related bloodstream infection (CRBSI); however, thrombophlebitis can also occur. Thrombophlebitis of the internal jugular vein (IJV) may present with symptoms, such as fever, lateral neck pain, and swelling, regardless of the presence or absence of infection; however, symptoms may be minor and easily overlooked. Sore throat is a well-known symptom of Lemierre's syndrome, but has not been reported in cases of thrombophlebitis without infection. We report two cases of HD catheter-associated IJV thrombophlebitis in patients that were diagnosed with sore throat.

Case presentation

Case 1 included a 58-year-old woman with diabetic nephropathy on HD. She was admitted to our hospital due to the occlusion of an arteriovenous fistula (AVF) for dialysis. A temporary HD catheter was placed in the right IJV until an arteriovenous graft (AVG) was fabricated. After admission, CRBSI was suspected because she developed fever; however, bacteremia was ruled out and a sore throat gradually developed. Contrast-enhanced computed tomography (CT) revealed thrombophlebitis of the right IJV. Anticoagulation therapy was initiated and she was discharged due to an improvement of symptoms. Case 2 included an 83-year-old man with end-stage renal disease due to hypertensive nephrosclerosis. He was admitted to our hospital because of AVF occlusion. A temporary HD catheter was inserted into the right IJV and an AVG was created. He had elevated C-reactive protein levels after catheter placement but was asymptomatic. When removing the catheter, he complained of throat discomfort. Ultrasonography of the neck revealed thrombotic obstruction of the right IJV, and contrast-enhanced CT revealed thrombophlebitis of the right IJV. Blood culture results were negative. He was discharged after anticoagulation therapy was started and symptoms improved.

Conclusions

The presence of sore throat leads to the diagnosis of IJV thrombophlebitis. Pharyngeal symptoms that develop after central venous catheter (CVC) placement should be differentiated from thrombophlebitis using a minimally invasive vascular ultrasound.

Real-world comparison of the last generation balloon-expandable and self-expanding valves in patients undergoing TAVI

Background/Introduction

The balloon expandable (BE) Edwards Sapien-S3/Ultra, and the self-expanding (SE) Medtronic Evolut-Pro represent the main volume of transcatheter aortic valve implantation (TAVI) procedures conducted worldwide.

Purpose

The present study represents the largest real-world comparison of periprocedural and short-term outcome between the aforementioned last generation devices.

Methods

Consecutive patients who had undergone TAVI with either the BE (S3/Ultra) or SE (Evolut-Pro/R-34mm if 34mm valve was required) device, in five centers were retrospectively studied. Periprocedural and short-term outcomes were recorded and compared.

Results

In total, 1341 patients (58.5% male) were treated with contemporary BE and SE valves (574 and 767pts with BE and SE respectively) and followed up for a median of 18.7 (IQR 30) months. Baseline demographics were similar between the two groups apart from severe left ventricle (LV) systolic impairment and extensive aorta calcification, being more prevalent amongst BE and SE groups respectively. Patients treated with the Evolut-Pro/R34mm device had significantly lower peak (16±9mmHg for SE vs 23.9±6mmHg for the BE valves, p=0.001) and mean (8.6±6mmHg SE vs 11.2±5.2mmHg BE, p=0.001) gradients at discharge.

Conversely, the BE group demonstrated significantly lower rates of at least moderate residual aortic regurgitation (AR) post-operatively (0.7% vs 5.2% for BE and SE valves respectively, p<0.001). Interestingly, the rate of new permanent pacemaker (PPM) required after the implantation in initially pacemaker-free patients, was higher for the S3/Ultra cohort compared to the self-expanding valve group (14.4% vs 12.3% respectively, p=0.001). No statistical difference was recorded between valve groups regarding cerebrovascular events (3.4% vs. 2.7% for SE and BE respectively, p=0.466), major vascular complications (4.2% vs. 3.0% for SE and BE respectively, p=0.251) and death to hospital discharge (1.6% vs. 2.9% for SE and BE respectively, p=0.117).

One-year Kaplan-Meier estimated survival was similar between the two groups (88.7% for BE vs. 91.4% for SE valves, plog-rank=0.093). When adjusting for age, extensive calcification of the aorta and baseline LV function all caused mortality hazard ratios were similar between patients treated with BE vs SE valves (HR 1.39; 95% CI 0.97 to 1.98, p=0.07).

Conclusions

Real life comparison of the last generation balloon expandable and self-expanding devices demonstrates superiority of the former in terms of residual PVL, at the expense of higher transvalvular gradients and higher need of new PPM implantation. The latter however may represent differences in center practices with regards to thresholds for permanent pacing. Long-term follow-up and future larger trials are required to establish any potential long-term difference in clinical outcomes and prognosis.

Funding Acknowledgement

Type of funding sources: None.

Real-world comparison of the last generation main balloon-expandable and self-expanding valves in patients undergoing TAVI. Does the type matter?

Background/Introduction

The balloon expandable Edwards Sapien-S3 and Ultra, and the self-expanding Medtronic Evolut-Pro and Evolut-R 34mm represent the main volume of transcatheter aortic valve implantation (TAVI) procedures conducted worldwide.

Purpose

In the present study, we aim to compare the peri-procedural and one-year clinical outcomes between these last generation devices.

Methods

Consecutive patients from the ATLAS (Athens-Tokyo-London Aortic Stenosis) registry, who had undergone TAVI with either the S3/Ultra or Evolut-Pro/R 34mm device, in four centers were retrospectively studied. In-hospital procedural characteristics and outcomes were recorded and compared. Kaplan-Meier estimated 1-year all-cause mortality was compared between groups.

Results

In total, 692 patients (352pts treated with S3/Ultra and 340pts with Evolut-Pro/R34mm device) were included in the analysis. Baseline demographics (age, coronary artery disease risk factors, logistic Euroscore and aortic valve hemodynamics) were similar between the two groups.

In terms of peri-procedural and short-term outcomes, patients treated with the Evolut-Pro/R34mm device had significantly lower peak (25.4±3.6mmHg for S3/Ultra vs 14.9±0.6mmHg for the self-expanding valves, p=0.002) and mean (10.7±0.3mmHg S3/Ultra vs 7.9±0.4mmHg Evolut PRO/R34, p<0.001) gradients at discharge.

Conversely, the S3 demonstrated significantly lower rates of at least moderate residual aortic regurgitation (AR) post-operatively (0.3% vs 4.8% for S3 and Evolut-Pro/R34mm respectively, p=0.001). Interestingly, the rate of new permanent pacemaker (PPM) required after the implantation in pacemaker-free patients on baseline, was higher for the S3/Ultra cohort compared to the self-expanding valve group (17.6% vs 11.7% respectively, p=0.054), however not reaching statistical significance yet. As expected, the need for balloon post dilatation of the implanted prosthesis was less among the S3/Ultra patients (5.5% vs 26.1%, p=0.001).

One-year Kaplan-Meier estimated survival was similar between the two groups (85.9% for S3 vs. 90% for Evolut-Pro/R34mm, plog-rank=0.071). Hazard ratio for all-cause mortality (Pro/R34 vs. S3/Ultra) after adjustment for gender and previous MI was similar between the groups (HR=0.73; 95% CI 0.47 to 1.14, p=0.165).

Conclusions

Real life comparison of the last generation balloon expandable and self-expanding devices demonstrates similar 1-year all-cause mortality. The S3/Ultra platforms, as compared to the Evolut-Pro/R34mm, demonstrate less paravalvular leak, at the expense of higher transvalvular gradients. Long-term follow-up and future larger trials are required to establish any potential long-term difference in clinical outcomes and prognosis.

Funding Acknowledgement

Type of funding source: None

1320Effectiveness of atrial flutter ablation line selection using SOUNDSTAR catheter

Background

Cavotricuspid isthmus (CTI) ablation for atrial flutter (AFL) shows a high success rate and effective for patients. However, operators experience difficulties in CTI ablation in some cases and need additional ablation for repeated recurrence. We investigated whether the SOUNDSTAR® (Biosense. Webster, Diamond Barr, CA, USA) catheter would be effective to select a CTI line of high therapeutic effect.

Methods

We have investigated the anatomy of around CTI by SOUNDSTAR® catheter and decided the CTI line using the anatomical information in AFL ablation (Figure1). We assumed two CTI lines of medial and lateral line. Medial CTI (M-CTI) line was more common and shorter line. Lateral CTI (L-CTI) line was uncommon and slightly longer line. We use 3.5mm tip catheter with NxT steerable introducer. The target Ablation Index (AI) was 400, and the target VisTtag™ interval was 6 mm or less.

Results

A total 30 of AFL ablated cases were investigated retrospectively. We surveyed 15 cases in M-CTI group and 15 cases in L-CTI group. Comparing the length of CTI in all cases, the length of M-CTI line was shorter than L-CTI line (M-CTI 32.1 ± 6.6mm vs. L-CTI 38.4 ± 8.3mm, n = 30, p <0.01). The atrial wall thickness of midsection and tricuspid valve (TV) side were thicker in M-CTI line (Midsection: M-CTI 4.0 ± 1.2mm vs. L-CTI 3.3 ± 0.8mm, n = 30, p <0.05, TV side: M-CTI 5.4 ± 1.4mm vs. L-CTI 4.3 ± 1.1mm, n = 30, p <0.05,). There was no difference in the required number of points to complete initial line (M-CTI 8.4 ± 1.6 vs. L-CTI 8.1 ± 1.7, n = 15, ns). Eustachian ridge in IVC side was thicker and higher in the M-CTI group (3.4 ± 3.3mm vs. 0.9 ± 1.9mm, n =30, p <0.01) and ablation on the Eustachian ridge showed instability of catheter placement. A lot of RF delivery was required on Eustachian ridge in M-CTI (2.6 ± 0.6 vs. 2.1 ± 0.7, n =15, p <0.05) and AI had resulted lower in M-CTI (351 ± 42.8 vs. 381 ± 27.1, n =15, p <0.05). Recurrence is more common in M-CTI group (9/15, 60% vs. 3/15, 20%). Recurrence sites in M-CTI group were distributed ((IVC side 3/9 (33%), midsection 5/9 (56%), TV side 5/9 (56%)) and multiple recurrences occurred in 3/9 (33%). Recurrence sites in L-CTI were only midsection of CTI (3/3, 100%).

Conclusions

CTI ablation at the shorter distance M-CTI, which is commonly selected, resulted in more recurrences due to the unevenness including Eustachian ridge and the myocardium thickness. However, ablation at slightly longer L-CTI line showed lower recurrence and effective for CTI ablation.

Abstract Figure 1

P6530Clinical outcomes of dialysis patients treated with current generation DES for left main distal bifurcation

Objectives

We assessed clinical outcomes after percutaneous coronary intervention (PCI) for unprotected left main (ULM) using current generation drug eluting stents (cDES) in hemodialysis (HD) patients compared to general populations.

Methods

We identified 1269 consecutive patients who underwent PCI for ULM distal bifurcation lesions. Of them, 563 patients were treated with cDES (512 non HD and 51 HD patients). The primary endpoint was target lesion failure (TLF) at 3 years, defined as a composite of cardiac death, target lesion revascularization (TLR) and myocardial infarction (MI).

Results

HD group was more likely to have diabetes mellitus (70.0% vs. 45.8%, p=0.002), peripheral artery disease (56.0% vs. 14.9%, p<0.001), and lower ejection fraction (52.6% vs. 56.3%, p=0.026). The rate of TLF at 3 years was significantly higher in the HD group (adjusted Hazard ratio [HR] 2.59; 95% confidence interval [CI], 1.54–4.37; p<0.001). Cardiac mortality was significantly higher in the HD group (adjusted HR 4.49; 95% CI, 2.07–9.74; p<0.001). The rates of TLR for LM-left anterior descending artery (LAD) and left circumflex ostium (LCXos) were significantly higher in the HD group (LMT-LAD: adjusted HR 3.10; 95% CI, 1.31–7.33; p=0.01, LCXos: adjusted HR 2.56; 95% CI, 1.32–4.94; p=0.005). The rate of MI was similar between the 2 groups.

Conclusions

Hemodialysis was strongly associated with adverse events after PCI for ULM distal bifurcation lesions even with cDES.

A case report of granulomatous polyangiitis complicated by tuberculous lymphadenitis

RATIONAL

Granulomatous polyangiitis (GPA) is a type of vasculitis involving medium and small arteries, typically affecting the upper and lower respiratory tract with coexisting glomerulonephritis. GPA is also characterized by necrotizing granulomatous inflammation and the presence of antineutrophil cytoplasm antibodies (ANCA). So far, various infections have lead to elevation of titers of serum ANCA, making it difficult to diagnose.

PATIENT CONCERNS

We report a 50-year-old woman who was diagnosed as tuberculous lymphadenitis. During the treatment by anti-tuberculosis (TB) drugs, rapidly progressive renal failure and pleurisy had appeared with elevated titer of PR3-ANCA. Renal biopsy revealed crescentic glomerulonephritis.

DIAGNOSIS

Renal biopsy revealed crescentic glomerulonephritis and diagnosis of GPA was made.

INTERVENTIONS

Steroid therapy had been started with continuation of anti-TB drugs.

OUTCOMES

Renal dysfunction had gradually recovered and pleurisy had disappeared with decreasing titer of PR3-ANCA.

LESSONS

This is the first report of GPA complicated by TB infection. When we encounter a case with rapidly progressive renal failure during the TB infection, complication of GPA should be suspected as 1 of the different diagnosis.

Experience of Lymphangiography as a Therapeutic Tool for Lymphatic Leakage After Kidney Transplantation

INTRODUCTION

Lymphatic leakage after kidney transplantation is a relatively frequent complication but sometimes resistant to treatment, and there is no fixed treatment algorithm. The effectiveness of therapeutic lymphangiography for postoperative lymphatic or chyle leakage has been reported, but few reports are available regarding patients who have undergone kidney transplantation. In this study, we report our experience with lymphangiography as a therapeutic tool for lymphatic leakage after kidney transplantation.

PATIENTS AND METHODS

Intranodal lymphangiography for lymphatic leakage was performed in 4 patients (3 male, 1 female; age range, 38 to 70 years old) after living kidney transplantation at the Osaka City University Hospital in Japan. The amount of drainage before lymphangiography was 169 to 361 mL/day. The procedure for intranodal lymphangiography was as follows: the inguinal lymph node was punctured under ultrasound guidance, and the tip of the needle was instilled at the junction between the cortex and the hilum, after which Lipiodol was slowly and manually injected.

RESULTS

Lymphangiography was technically successful in 3 out of the 4 patients. In all successful cases, the amount of drainage decreased and leakage finally stopped without additional therapy such as sclerotherapy or fenestration. In 2 cases, we were able to directly detect the leakage site using lymphangiography. The time between lymphangiography and leakage resolution ranged from 8 to 13 days. There were neither complications of lymphangiography nor recurrence of lymphatic leakage in the successful cases.

CONCLUSIONS

Intranodal lymphangiography may be not only a diagnostic tool but also an effective, minimally-invasive, and safe method for treatment of lymphatic leakage resistant to drainage after kidney transplantation.

Estimation of the following Cardiac Output Using Sympathetic Tone and Hemodynamics for the Control of a Total Artificial Heart

A sympathetic neurogram is potentially useful for the development of a real time total artificial heart (TAH) control system. We used sympathetic tone and hemodynamic derivatives to estimate the following cardiac output in acute animal experiments using adult mongrel dogs. Moving averages of the mean left atrial pressure and mean aortic pressure were used as parameters of the preload and afterload, respectively. Renal sympathetic nerve activity (RSNA) was employed as a parameter of sympathetic tone. Equations for the following cardiac output were calculated using multiple linear regression analysis of the time series data. A significant correlation was observed between the estimated and following measured cardiac output. These results suggest the potential usefulness of the sympathetic neurogram for the real time TAH automatic control system.

Clinical Experience of Late Conversion From Antimetabolites With Standard Exposure Calcineurin Inhibitors to Everolimus With Calcineurin Inhibitor Minimization in Stable Kidney Transplant Recipients With Good Renal Function

INTRODUCTION

This study describes our clinical experience of late conversion from antimetabolites with standard exposure calcineurin inhibitors (CNIs) to everolimus with CNI minimization in stable kidney transplant recipients with good graft function.

PATIENTS AND METHODS

A 1-year retrospective pilot study of 26 kidney recipients converted from antimetabolites with standard exposure CNIs to everolimus with CNI minimization was performed. The recipients enrolled in this study had normal or slightly impaired renal function defined as a serum creatinine value <2.0 mg/dL, and normal or slightly increased albuminuria defined as a urinary albumin excretion rate <100 mg/g creatinine.

RESULTS

The median time from transplant to conversion was 39.5 months posttransplant (range, 3-275). Treatment with everolimus was stopped owing to adverse events in 11 patients (42.3%). In the analysis of the patients in whom everolimus was maintained, the mean estimated glomerular filtration rate (eGFR) significantly increased from 50.7 ± 11.9 mL/min/1.73 m(2) at baseline to 53.6 ± 13.9 mL/min/1.73 m(2) at 1 year after conversion. In the patients in whom everolimus was stopped during the observation period, there was no difference in eGFR between baseline and 1 year after conversion.

CONCLUSIONS

This study demonstrated that, among the patients converted to everolimus at a late stage, there was no deterioration in renal function whether everolimus was maintained or stopped within 1 year after conversion.

Investigation of urinary angiotensinogen in renal transplant recipients

BACKGROUND

Recent studies have indicated that angiotensinogen (AGT) is also locally produced in the kidney and that urinary AGT is a marker of local renal renin-angiotensin system activation. Because urinary AGT levels are significantly higher in patients with chronic kidney disease (CKD) than in patients without CKD and correlate with urinary albumin and other levels, urinary AGT is increasingly recognized as a marker for CKD monitoring, prognosis, and treatment. In this study, we investigated urinary AGT levels in renal transplant recipients.

METHODS

Among the patients who were treated as outpatients at the Department of Urology of Osaka City University Hospital from March 2012 to April 2013, 146 stable renal transplant recipients and 50 donors who gave informed consent were studied. Urinary AGT and creatinine (Cr) levels were measured. The urinary AGT-to-Cr ratio was calculated, and its correlation with clinical parameters was examined.

RESULTS

The urinary AGT-to-Cr ratio of the renal transplant recipients was significantly higher than that of the renal transplant donors (P = .0143). Furthermore, the urinary AGT-to-Cr ratio had a significantly positive correlation with the urinary albumin-to-Cr ratio (ACR; r = 0.39, P < .0001), while on the other hand, it had a significantly negative correlation with estimated glomerular filtration rate (eGFR; r = -0.31, P = .0002). Multiple linear regression analysis of factors associated with eGFR showed that urinary AGT was a significant and independent factor after adjusting for age, sex, and ACR.

CONCLUSIONS

Our results indicated that urinary AGT levels were elevated in renal transplant recipients. In addition, urinary AGT significantly correlated with renal function and degree of albuminuria.

Poor glycemic control and decreased renal function are associated with increased intrarenal RAS activity in Type 2 diabetes mellitus

AIMS

The renin-angiotensin system (RAS) plays an important role in the pathogenesis of diabetic nephropathy. The aim of the present study was to investigate intrarenal RAS activity in patients with type 2 diabetes (T2DM).

METHODS

We measured urinary angiotensinogen, a reliable biomarker of intrarenal RAS activity, in 14 controls without T2DM, 25 T2DM patients without nephropathy, 11 chronic kidney disease (CKD) patients without T2DM and 46 CKD patients with T2DM. Associations between urinary angiotensinogen and clinical parameters were examined.

RESULTS

Compared with the controls, urinary [angiotensinogen:creatinine] were significantly higher in T2DM patients without nephropathy (4.70 ± 2.22 vs. 8.31 ± 5.27 μg/g, p=0.037). Age, hemoglobin A1c (HbA1c) and fasting plasma glucose correlated significantly and positively with the log{urinary [angiotensinogen:creatinine]} (r=0.632, p=0.007; r=0.405, p=0.027; r=0.583, p=0.003, respectively) in T2DM patients without nephropathy. In contrast, the urinary [angiotensinogen:creatinine] were not significantly different between CKD patients with and without T2DM (22.7 ± 27.8 vs. 33.5 ± 40.8 μg/g, p=0.740); although they were significantly higher when compared with non-CKD patients. In the CKD patients with T2DM systolic blood pressure, serum creatinine, estimated glomerular filtration rate and urinary [albumin:creatinine] correlated significantly with the log{urinary [angiotensinogen:creatinine]} (r=0.412, p=0.004; r=0.308, p=0.037; r=-0.382, p=0.001; r=0.648, p<0.001, p<0.001, respectively).

CONCLUSIONS

Our findings indicate that poor glycemic control is significantly associated with intrarenal RAS activity in T2DM patients without nephropathy, and that decreased renal function is significantly associated with intrarenal RAS activity in CKD patients with T2DM.

Which patients could benefit the most from bioresorbable vascular scaffold implant: from clinical trials to clinical practice

Bioresorbable scaffold technology has evol-ved over the last few years with a number of devices either available or under clinical and preclinical investigation. The absence of a permanent metallic segment in the treated vessel wall has the potential of addressing some of the issues still encountered with metallic drug-eluting stents (DES) despite improvements in stent platform, polymer and drug elution. To date however, the use of bioresorbable vascular scaffolds (BVS) has largely been restricted to patients recruited into clinical trials with a relatively small number of "real-world" patients treated with these devices. Here we explore the issue of BVS use in "real-world" patients and try to identify, on the basis of our experience, the subset of patients that could benefit the most.

PEMFC Development at Asahi Glass Co., Ltd

Perfluorinated ion exchange membranes were studied and the membrane technology for PEMFC has been developed. Thermal stability, mechanical strength, water content, AC specific resistance and gas permeability were measured. The influence of membrane thickness on gas permeability and the influence of incorporation of cations on water content and AC specific resistance of Flemion® and Nafion® 117 were estimated. Gas permeation rates of the membranes decreased in inverse proportion to the increase of the membrane thickness and gas permeability coefficients were nearly constant and independent of the thickness. Hydrogen permeation rates of Flemion®S at 70°C were converted to 2.1 mA/cm2 as cunent density. Flemion®R-electrode assembly showed to maintain stable perfonnance for over 3,500hr. Furthermore, it was found that usage of thinner membranes or one with higher ion-exchange capacity gave not only lower intemal cell voltage but also higher iR-free cell voltage. PTFE-yam embedded type membrane (Flemion®Mc and Sc) and PTFE-flbril dispersed type (Flemion®R12) was examined to afford improvement in mechanical strength at moist and high temperature atmosphere. Flemion®Sc (80!am) was examined to give high cell performance of 0.67V at 0.5A/cm2, 80°C, I ata. Flemior®Mc-electrode assembly was examined to keep stable performance during the life test of over 1,500hr.

Haplotype-based case-control study on human apurinic/apyrimidinic endonuclease 1/redox effector factor-1 gene and essential hypertension

BACKGROUND

Oxidative DNA damage is involved in the pathophysiology of essential hypertension (EH), which is a multifactorial disorder. Apurinic/apyrimidinic endonuclease 1/redox effector factor-1 (APE1/REF-1) is an essential endonuclease in the base excision repair pathway of oxidatively damaged DNA, in addition to having reducing properties that promote the binding of redox-sensitive transcription factors. Blood pressure in APE1/REF-1-knockout mice is reported to be significantly higher than in wild-type mice. The aim of this study was to investigate the relationship between EH and the human APE1/REF-1 gene through a haplotype-based case-control study using single-nucleotide polymorphisms (SNPs).

METHODS

We selected five SNPs in the human APE1/REF-1 gene (rs1760944, rs3136814, rs17111967, rs3136817, and rs1130409), and performed case-control studies in 265 EH patients and 266 age-matched normotensive (NT) subjects.

RESULTS

rs17111967 was found to show nonheterogeneity among Japanese subjects. There were no significant differences in the overall distribution of genotypes or alleles for each SNP between EH and NT groups. In the overall distribution of the haplotype-based case-control study constructed based on rs1760944, rs3136817, and rs1130409, the frequency of the G-T-T haplotype was significantly higher in the EH group than in the NT group (2.1% vs. 0.0%, P = 0.001). Multiple logistic regression analysis also revealed significant differences for the G-T-T haplotype, even after adjustment for confounding factors (OR = 8.600, 95% CI: 1.073-68.951, P = 0.043).

CONCLUSIONS

Based on the present results, the G-T-T haplotype appears to be a genetic marker of EH, and the APE1/REF-1 gene appears to be a susceptibility gene for EH.

Haplotype-based case-control study of receptor (calcitonin) activity-modifying protein-1 gene in cerebral infarction

Calcitonin gene-related peptide (CGRP) receptor is a complex molecule that consists of calcitonin receptor-like receptor and receptor activity-modifying protein-1 (RAMP1). It was recently reported that RAMP1-deficient mice (RAMP1(-/-)) showed inflammatory responses with a transiently significant increase in serum CGRP levels and proinflammatory cytokines when compared with RAMP1(+/+) mice. The aim of this study was to investigate the relationship between the human RAMP1 gene and cerebral infarction (CI) using single-nucleotide polymorphisms (SNPs) in a Japanese population. We selected six SNPs in the human RAMP1 gene (rs3754701, rs3769048, rs7557078, rs1584243, rs10199956 and rs7590387) and performed a case-control study using each SNP and haplotype in 171 CI patients and 234 controls. There were no significant differences in overall distribution of genotype and allele frequencies of the SNPs between the CI and control groups. However, there was a significant difference in overall distribution between the CI and control groups (P<0.001) in the haplotype-based case-control study with the combinations of rs3754701-rs3769048-rs7590387. The T-A-C susceptibility haplotype for CI was significantly more frequent than in the control group (P=0.0024). The results suggest that the T-A-C haplotype is a genetic marker for CI, and that RAMP1 or neighbouring genes are associated with increased susceptibility to CI.

Effect of lectins on the transport of food ingredients in Caco-2 cell cultures

We investigated the effect of several lectins, such as soy bean lectin (SBA), concanavalin A (Con A), and wheat germ agglutinin (WGA), on the transport of some food ingredients (isoflavones, quercetin glycosides, carnosine/anserine) across Caco-2 cell monolayers. After incubation of food ingredients (0.03 approximately 2 mmol/L) in the presence or absence of lectins (1 approximately 180 microg/ml) on the apical side, aliquots were taken from the apical and basolateral solution, and were subjected to HPLC analysis. We also examined the effect of lectins on the permeability of the tight junction by measuring the transepithelial electrical resistance (TER) value of the Caco-2 cell monolayer. Isoflavones, which was not transported to the basolateral solution without lectins, could be transported in the presence of lectins, whereas their aglycones were detected at the same levels with or without the lectin treatment. The transport of quercetin glycosides also increased in the presence of lectins, however, that of peptides was not affected by the lectins. Con A and WGA, but SBA, decreased the TER value, indicating that Con A and WGA increased the transport via paracellular pathway, whereas SBA did via a different pathway.

Thymidine phosphorylase levels as a prognostic factor in renal cell carcinoma

OBJECTIVE

To investigate the relationship between thymidine phosphorylase (TP), a vascular growth factor, and established prognostic factors for renal cell carcinoma (RCC), e.g. histological grade or Tumour-Node-Metastasis (TNM) classification.

PATIENTS AND METHODS

TP levels were measured in RCC tissue (tumour TP) and in adjacent non-neoplastic kidney tissue (normal tissue TP), using a sandwich-type enzyme-linked immunosorbent assay. The 59 patients, diagnosed with organ-confined RCC before surgery and who had undergone radical nephrectomy, were divided into two groups according to their prognosis after surgery. Group 1 (nine patients) had a poor prognosis and group 2 (50) had no evidence of disease within a 65-month follow-up. The relationships among TP level, TNM classification, histological subtypes, V factor and prognosis, and of tumour TP to normal tissue TP levels were investigated. Multiple regression analysis was used to determine the importance of factors associated with increased TP levels.

RESULTS

Normal tissue TP levels correlated with histological grade (r = 0.31, P < 0.01); in patients with venous invasion or with a poor prognosis, the levels were significantly higher than in those without (P < 0.05 and < 0.001, respectively). The normal tissue TP levels were also significantly higher in the non-clear cell than in the clear cell subtype. Multiple regression analysis showed that the independent factor associated with elevated normal tissue TP levels was histological grade (R2 = 0.189, P < 0.01). There was no correlation between tumour TP and other factors.

CONCLUSION

Normal tissue TP levels in localized hypervascular RCC were associated with histological grade. These data suggest that normal tissue TP levels could be a prognostic factor.

Biodegradation of triazine herbicides on polyvinylalcohol gel plates by the soil yeast Lipomyces starkeyi

The soil yeast Lipomyces starkeyi was tested for its ability to degrade triazine herbicides. Polyvinylalcohol (PVA) was employed as a solid medium in culture plates instead of agar. The cell sizes of the control (without nitrogen source) on the PVA gel plate were much smaller than those on the agar gel plate. The difference between the diameters of the sample and control colonies on the PVA gel plate were almost twice those of the colonies on the agar gel plate (1.9 and 1.0 mm, respectively). Thus, the PVA gel plate is much better than the agar plate for evaluating the degree of utilization of a sole nitrogen source. The yeast grew well (more than 4 mm in diameter) with 1,3,5-triazine or cyanuric acid as nitrogen source. In addition, melamine and thiocyanuric acid inhibited growth of the yeast, and the sizes of colonies were smaller than those of the control. All triazine herbicides tested (simazine, atrazine, cyanazine, ametryn, and prometryn) could be degraded and assimilated by L. starkeyi.

Viable cytophaga-like bacterium in the 0.2 microm-filtrate seawater

A strain of the Cytophaga-like bacterium (CLB), Nano-1, was isolated from the 0.2 microm-filtrate of natural seawater. Both cellular fatty acid and 16S rDNA sequence analyses indicated that Nano-1 is closely affiliated to the marine gliding CLB genus, Microscilla. Nano-1 was observed to undergo cyclic morphological change typical of the genus Microscilla, and sub-0.2-microm cells were formed in the late stationary phase. The sub-0.2-microm cells were repeatedly revived and subcultured. Formation of the sub-0.2-microm cells seems to be adaptive for oligotrophic growth and starvation survival.

Surgical treatment of pancreatic cancer. Does extended lymphadenectomy provide a better outcome?

The rate of curative resection of pancreatic cancer has increased as a result of extended operations, but this has not led to any significant improvement in postoperative outcome. No definite conclusions were drawn in retrospective studies comparing outcome after standard and extended operations, and there was almost no difference in outcome between the two groups in a recent prospective randomized study. In addition, extended procedures are very stressful operations that, in most instances, impair the patient's quality of life (QOL). As a result, the need for performing extended surgery to treat pancreatic cancer has come into question. The outcome of advanced cancer in patients in whom curative resection cannot be achieved by extended operations is extremely poor, and we believe that, in such patients, priority should be given to QOL, by selecting bypass or limited operations instead. It is hoped that the value of extended surgery will be clarified by a very carefully planned multicenter prospective randomized study in the future.

Change in the diameter of the radial artery transradial intervention using a 6 French system in Japanese patients

We examined the change in the diameter of the radial artery after transradial intervention (TRI) using a 6 French system in 50 Japanese patients in order to investigate whether the radial artery would be preserved after TRI. In all cases, the Allen test was normal and repeated puncture was possible at the TRI site 3 months after TRI. Moreover, the appearance of new stenosis or thinning throughout the radial artery at the TRI site was not seen. The diameter of the radial artery 3 months after TRI tended to be somewhat smaller at both the proximal and distal sites; however, there was not a statistically significant change between the diameter before and 3 months after TRI. Our results show that the radial artery will be preserved after TRI using a 6 French system in selected Japanese patients.