Communication: long-lived neutral H2 in hydrogen migration within methanol dication

The ejection of triatomic hydrogen molecular ions HD2(+) and D3(+) from CD3OH(2+) is investigated by first-principle molecular dynamics simulation. Two C-D chemical bonds are found to be broken to form a neutral D2 moiety that vibrates, rotates, and moves for a relatively long period of time (20-330 fs) towards a transition state leading to the ejection of HD2(+) or D3(+). The formation of such a long-lived neutral D2 moiety within a hydrocarbon molecule interprets well the recent experimental findings of the long lifetime of doubly charged energized hydrocarbon molecules prior to the ejection of H3(+).

Propagation Characteristics of Seismic Waves Taking Stratigraphic Composition into Consideration

In this paper, soil-water coupled dynamic analyses are carried out to investigate the influence of stratigraphic composition on the propagation properties of the seismic waves. SYS Cam-clay model is used as the constitutive model which can describe the different state of clayey and sandy soils. Two cases are considered for the composition of ground: one is the sandy ground with diluvial sand, alluvial sand and reclaimed sand; the other one is the clayey layer at the ground surface. It is found that for the sandy ground even though there is certain amplification of the input acceleration wave during the dense sand layer the subsequent seismic waves through the loose sand layers are attenuated significantly due to the occurrence of the liquefaction. While for the clayey ground, even though there is no risk of liquefaction damages at the ground surface the acceleration amplitude is greatly amplified and there is a risk that the structure itself would fail in the strength.

Anticoagulant and antiplatelet therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention

The prevalence, intensity, safety, and efficacy of oral anticoagulation (OAC) in addition to dual antiplatelet therapy (DAPT) in "real-world" patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) have not yet been fully evaluated. In the Coronary REvascularization Demonstrating Outcome Study in Kyoto registry cohort-2, a total of 1,057 patients with AF (8.3%) were identified among 12,716 patients undergoing first PCI. Cumulative 5-year incidence of stroke was higher in patients with AF than in no-AF patients (12.8% vs 5.8%, p <0.0001). Although most patients with AF had CHADS2 score ≥2 (75.2%), only 506 patients (47.9%) received OAC with warfarin at hospital discharge. Cumulative 5-year incidence of stroke in the OAC group was not different from that in the no-OAC group (13.8% vs 11.8%, p = 0.49). Time in therapeutic range (TTR) was only 52.6% with an international normalized ratio of 1.6 to 2.6, and only 154 of 409 patients (37.7%) with international normalized ratio data had TTR ≥65%. Cumulative 5-year incidence of stroke in patients with TTR ≥65% was markedly lower than that in patients with TTR <65% (6.9% vs 15.1%, p = 0.01). In a 4-month landmark analysis in the OAC group, there was a trend for higher cumulative incidences of stroke and major bleeding in the on-DAPT (n = 286) than in the off-DAPT (n = 173) groups (15.1% vs 6.7%, p = 0.052 and 14.7% vs 8.7%, p = 0.10, respectively). In conclusion, OAC was underused and its intensity was mostly suboptimal in real-world patients with AF undergoing PCI, which lead to inadequate stroke prevention. Long-term DAPT in patients receiving OAC did not reduce stroke incidence.

Pretreatment with buthionine sulfoximine enhanced uptake and retention of BSH in brain tumor

To determine the influence of buthionine sulfoximine (BSO) on boron biodistribution after sulfhydryl borane (BSH) administration for boron neutron capture therapy, the effectiveness of the combination of BSO with sulfhydril- (BSH) and non-sulfhydril (B12H12 and BNH3) boron compounds, and the interval between BSO and BSH administration, the retention of boron in tissues have been evaluated using a 9L rat tumor model. Simultaneous administration of BSH and BSO showed significantly higher boron accumulation compared to that without BSO, however there was no difference in tissue boron level between B12H12 and BNH3 administration with BSO or without BSO. The longer interval (6h) between BSH and BSO administration related to the highest boron concentration in the brain and subcutaneous tumors compared to shorter intervals (0.5, 3h). Boron concentration in subcutaneous and brain tumors was maintained for 6 and 12h after the administration of BSH following BSO pretreatment.

Vitamin D activates the Nrf2-Keap1 antioxidant pathway and ameliorates nephropathy in diabetic rats

BACKGROUND

Diabetic nephropathy is a major risk of end-stage kidney disease. Many complex factors relate to the progression of diabetic nephropathy. Using nonobese type 2 diabetes model rats, we confirmed that oxidative stress was a crucial factor. Because recent studies suggest that vitamin D could suppress oxidative stress, we explored whether the active vitamin D analog, maxacalcitol, could also attenuate oxidative stress and prevent the progression of diabetic nephropathy.

METHODS

Diabetic rats aged 20 weeks were divided into 3 groups and treated with insulin, maxacalcitol, and vehicle. At age 30 weeks, blood and urine analyses, renal histology, immunohistochemistry, real-time polymerase chain reaction, and western blot were performed.

RESULTS

Although maxacalcitol reduced albuminuria and mesangial matrix expansion, no significant differences were observed in blood pressure and creatinine clearance among the 3 treatment groups. Systemic and intrarenal oxidative stress was reduced by maxacalcitol therapy. Expressions of nuclear factor-κB and nicotinamide adenine dinucleotide phosphate oxidase in the kidney also decreased in the insulin-treated and maxacalcitol-treated groups but increased in the vehicle-alone group. In addition, the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) decreased and Kelch-like erythroid cell-derived protein with CNC homology (ECH)-associated protein 1 (Keap1) increased in the vehicle-treated group; however, these expressions were restored in the maxacalcitol- and insulin-treated groups.

CONCLUSIONS

It is suggested that maxacalcitol attenuates the progression of diabetic nephropathy by suppression of oxidative stress and amelioration of the Nrf2-Keap1 pathway in nonobese type 2 diabetes without significant changes in blood pressure and glomerular filtration rate.

Renin-Angiotensin system inhibitors reduce serum asymmetric dimethylarginine levels and oxidative stress in normotensive patients with chronic kidney disease

Background/Aims

The purpose of our study was to elucidate the relationship between asymmetric dimethylarginine (ADMA) and intrarenal lesions and to determine the effect of renin-angiotensin system inhibitors (RAS-Is) on serum ADMA levels, nitric oxide (NO) synthesis and oxidative stress in normotensive patients with chronic kidney disease (CKD).

Methods

This study included 23 normotensive patients with chronic glomerulonephritis and normal or mildly impaired renal function who underwent renal biopsy. We evaluated the relationship between serum ADMA levels and intrarenal lesions, and examined renal function, urinary protein excretion, ADMA levels, NO synthesis, oxidative stress and blood pressure (BP) before and 3 months after starting the treatment with RAS-Is.

Results

Serum ADMA levels were correlated only with arterial intimal fibroplastic thickness. Despite comparable renal function and BP, serum ADMA levels and excretion of urinary protein excretion significantly decreased, and urinary NO metabolite excretion significantly increased after starting the treatment with RAS-Is. Oxidative stress markers also tended to be reduced by the treatment.

Conclusion

These findings suggest that RAS-Is improve the NO system and decrease oxidative stress in normotensive patients with CKD. In addition, ADMA may be associated with intrarenal lesions and can be a useful marker for the effects of treatment in the early stages of CKD.

Marked elevation of serum hyaluronan levels in collagenofibrotic glomerulopathy

Collagenofibrotic glomerulopathy is a rare glomerular disease characterized by the massive deposition of type III collagen in mesangial and subendothelial spaces. We observed markedly increased serum hyaluronan levels in patients with collagenofibrotic glomerulopathy; levels in three patients were more than 1,000-times greater than the normal upper limit. However, one kidney transplant patient had normal serum hyaluronan levels. We found that serum levels and activities of the enzyme hyaluronidase were normal, and hyaluronan was not markedly deposited in the mesangial or subendothelial spaces. Our findings suggest that serum hyaluronan levels may be a specific diagnostic marker of collagenofibrotic glomerulopathy, and kidney transplantation may alleviate marked increases in serum hyaluronan.

Postoperative Clostridium difficile infection with PCR ribotype 078 strain identified at necropsy in five Thoroughbred racehorses

Clostridium difficile is an important cause of acute enterocolitis in horses. We describe five cases of C difficile infection occurring postoperatively in Thoroughbred racehorses. Following diarrhoea or colic accompanied by a marked increase in packed cell volume (to ≥60 per cent) and leucopenia (≤4000 cells/μl) within two to four days after surgery in all five horses, four of them died or were euthanased because of colitis or severe diarrhoea. In these four horses, necrotising entero-typhlo-colitis was revealed by postmortem examination, and C difficile was recovered from the contents of the small and/or large intestine. The remaining horse was euthanased because of marked decline in general condition and the presence of a lung abscess, from which C difficile was isolated. The horse had had severe postoperative diarrhoea before the onset of respiratory disorder; laboratory tests for C difficile were not performed on the faeces. All C difficile isolates were toxin-A-positive, toxin-B-positive and actin-specific ADP-ribosyltransferase (CDT)-positive. The isolates were indistinguishable by pulsed field gel electrophoresis analysis, PCR ribotyping, and slpA sequence typing, and the slpA sequences and PCR ribotype patterns were identical to those of known PCR type 078. This case sequence might have been healthcare-associated infection, although there was about a four-month interval between each disease onset.

A simplified pull-through angioplasty technique without a snare device. A technical note

The pull-through angioplasty technique allows stable wire tension and stabilization of the device during the procedure. In this technique, a guide wire is passed from one sheath to another, usually with the aid of a snare device. We describe the treatment of occlusive subclavian artery disease and lesion at the origin of the vertebral artery employing a brachiofemoral pull-through technique without using a snare device. In this technique, the guide wire is advanced from the femoral artery to the brachial artery. The guide wire is directly inserted into the sheath placed at the brachial artery. The brachial artery is compressed proximal to the point of sheath insertion to prevent bleeding. The sheath is extracted temporally and the guide wire is caught outside of the body. The sheath is then introduced again through the guide wire. We used the pull-through technique without a snare device in seven cases, and we were able to build the pull-through system in six of these cases without a snare device. This pull-through technique without a snare device is not difficult to use, and may reduce the time and cost of angioplasty procedures.

Anti-oxidative effect of vitamin D analog on incipient vascular lesion in non-obese type 2 diabetic rats

BACKGROUND/AIMS

Vascular disease is one of the critical complications of diabetes. A growing body of evidence suggests that oxidative stress plays a key role for vascular disease progression. Recent studies have demonstrated a strong link between vitamin D and cardiovascular disease.

METHODS

We investigated the anti-oxidative effects of a vitamin D analog, 22-oxacalcitriol (maxacalcitol), on vascular lesions in type 2 diabetic rats. We used Spontaneously Diabetic Torii (SDT) rats, a model of non-obese type 2 diabetes. At 20 weeks of age, SDT rats were randomly divided into three groups: diabetes mellitus (DM, n = 10), DM + maxacalcitol (DM + D, n = 10), and DM + insulin (DM + I, n = 10). The rats were sacrificed at 30 weeks for the evaluation of blood and urine samples as well as histopathology and mRNA expression in the aorta.

RESULTS

Urinary 8-hydroxydeoxyguanosine (8-OHdG) excretion and the number of 8-OHdG-positive cells were significantly lower in the DM + I and DM + D groups than in the DM group. Real-time polymerase chain reaction analysis demonstrated that NADPH p22 phox and NADPH p47 phox mRNA levels were markedly decreased in the DM + I and DM + D groups compared with the DM group. Furthermore, the mRNA expression of MCP-1, ICAM-1 and VCAM-1 was significantly reduced in the DM + I and DM + D groups compared with the DM group.

CONCLUSION

Our results suggest that the vasoprotective effects of vitamin D are mediated by reducing oxidative stress.

Parathyroid enlargement at dialysis initiation in patients with chronic kidney diseases

The kidney chiefly maintains homeostasis of water, electrolytes, and other solutions. When kidney function is reduced, mineral metabolism is disrupted. Mineral and bone disorder in patients with chronic kidney disease associates with increased cardiovascular risk and mortality; however, management of chronic kidney disease-mineral and bone disorder in predialysis patients remains controversial. This study investigates the association between parathyroid enlargement at dialysis initiation and hyperparathyroidism management in dialysis patients. We enrolled 72 patients at dialysis initiation in this study. Using parathyroid sonography, we categorized patients based on presence (detected group; N = 18) or absence (undetected group; N = 54) of enlarged parathyroid glands and assessed the clinical characteristics and laboratory findings. A literature review of ultrasound evaluations of secondary hyperparathyroidism was conducted. Ultrasonography revealed enlarged parathyroid glands in 18 patients (25%). Serum intact parathyroid hormone levels were high in patients with enlarged parathyroid glands; however, of the 29 patients with intact parathyroid hormone levels <240 pg/mL, four had enlarged parathyroid glands. Eight of the 29 patients with serum phosphorus and calcium levels within the optimal range had enlarged parathyroid glands. Twenty of these 29 patients were followed up at 38 ± 17 months (at least 3 months): enlarged parathyroid glands were detected in 6. During follow-up, serum intact parathyroid hormone levels were significantly higher in the detected group compared with the undetected. In conclusion, enlarged parathyroid glands are frequently detected at dialysis initiation, potentially predicting the persistence of secondary hyperparathyroidism and the need for strict management.

Association between AST-120 and abdominal aortic calcification in predialysis patients with chronic kidney disease

BACKGROUND

Vascular calcification is associated with mortality and cardiovascular events in patients with chronic kidney disease. AST-120, which adsorbs uremic toxins, is reported to reduce the risk of cardiovascular disease and death in chronic kidney disease patients. The aim of the current study was to investigate the association between abdominal aortic calcification and the use of AST-120 in predialysis chronic kidney disease patients.

METHODS

A retrospective analysis was conducted including 199 predialysis chronic kidney disease patients (stages 4 and 5) who underwent abdominal plain computed tomography in our institution between 2005 and 2010. Abdominal aortic calcification was assessed by aortic calcification index (ACI). Patients were divided into two groups based on whether or not AST-120 was administered for at least six months, and ACI was compared between the two groups.

RESULTS

The aortic calcification index was significantly lower in patients taking AST-120 [12.2 (2.5-30.3) vs. 25.7 (13.4-45.3) %, P < 0.001]. According to multivariate linear regression analysis, the use of AST-120 was independently and significantly correlated with ACI after adjusting for confounding factors.

CONCLUSIONS

The use of AST-120 was independently associated with less aortic calcification in predialysis chronic kidney disease patients.

Effect of enzyme replacement therapy on serum asymmetric dimethylarginine levels, coronary flow reserve and left ventricular hypertrophy in patients with Fabry disease

Background

Fabry disease (FD) is a rare disorder and one of the causes of progressive renal and cardiac dysfunction. FD results from an X-linked recessive lysosomal storage disorder caused by a defect in the gene encoding lysosomal α-galactosidase A. Although accumulation of globotriaosylceramide leads to renal and cardiac manifestations, the precise mechanisms remain unclear. Coronary microvascular dysfunction may be one of the causes of cardiac complications in FD. We aimed to assess coronary flow reserve (CFR) and the effect of enzyme replacement therapy (ERT) on coronary microvascular dysfunction.

Methods

Four FD patients who had never received ERT were included. The serum asymmetric dimethylarginine (ADMA) level, as a marker of endothelial dysfunction, was measured. Two-dimensional guided M-mode echocardiography was performed to measure left ventricular wall mass. Adenosine-triphosphate stress transthoracic Doppler echocardiography was used to measure CFR before starting ERT and at 3, 6 and 12 months.

Results

All the patients tolerated ERT without any side effects. At the baseline, two patients had impaired CFR, increased left ventricular mass index (LVMI) and elevated serum ADMA levels. Twelve months after starting ERT, CFR was increased in all patients, and LVMI and serum ADMA levels decreased in two patients. Furthermore, serum ADMA levels significantly correlated with CFR (r = −0.576, P < 0.05) and LVMI (r = 0.874, P < 0.0001).

Conclusions

The results suggest that ERT prevented the progression of cardiac abnormalities, possibly by improving coronary microvascular dysfunction. ADMA may be a useful surrogate marker in FD.

Multiple cerebral aneurysms with persistent primitive trigeminal artery

We report a patient with a persistent primitive trigeminal artery (PPTA) detected incidentally during cerebral angiography for the ruptured aneurysm. Cerebral angiography revealed a PPTA and eight anterior circulation cerebral aneurysms. Although cerebrovascular fragility, hemodynamic stress and hypertension are well known as etiologic factors for development of cerebral aneurysms, there is a known association of aneurysms with a PPTA, fetal carotid-basilar anastomosis. Furthermore, this case is rare from the viewpoint of aneurysm multiplicity.