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Elucidate the role of the addition of calcium sulfate compound (CS) in experimentally manufactured dental calcium silicate cement (CSC) with the variation of hydration type of CS. Experimental CSC was synthesized by solid state reaction at 1,450℃. After treating the obtained clinker (mainly C3S with LSF 98.19) by ball milling, vibration milling, and finally jet milling, fine particles (mean 2.92 um, D90= 4.82 um) were obtained. After adding radiopacifying element (20 wt% ZrO2), different kinds of CS compounds (orthorhombic anhydrite, hemihydrate, dihydrate) were additionally added to the powder to control the setting and handling behaviors. For addition percentage of CS, 5 wt% adding condition was selected. Flow (ISO and LVDT method), Gilmore setting time, and penetration resistance were tested to evaluate the rheological properties during the setting reaction and compressive strength, were measured. For the wash-out resistance test, samples (400 rpm spinning) set for 150 s were exposed to water jet (60 mL/min, 18 G needle, 30 mm distance), and the eroded sample surfaces were 3D scanned, and the eroded sample volumes calculated with Catia V5 program. MTT cell viability and antibacterial activity were evaluated. The mean and S.D. values of physical properties are shown in Table 1. The type of CS significantly affected the setting time and degree of flowability (p0.05) compared to Control (without extract). The CV at 50% dilution satisfied the ISO requirement of above 70%. However, CV in extract with no dilution were lower than 70% for all the tested groups. Addition of CS in CSC increased antibacterial activity against E. coli. Inhibition zone could not be observed for all groups against E. faecalis. Selectively using different types of CS in CSC could be an efficient manufacturing tactic to satisfy the different property requirements in various clinical cases of sealing, pulpotomy, perforation, or retrograde filling, etc. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to examine the relationships between subjective taste sensations and electrogustometry (EGM) findings in patients with taste disturbances according to the presence of burning mouth (BM) symptoms. Forty-six patients were included and asked to complete a questionnaire that contained questions on subjective taste sensations for the four basic taste qualities and the pattern of taste disorders such as ageusia, hypogeusia and dysgeusia. EGM was performed to measure detection thresholds. To examine the influence of BM symptoms, patients were divided into two groups: patients with and without BM symptoms. The patients consisted of 11 men and 35 women. The group without BM symptoms (n = 26) had significantly lower degrees of subjective taste sensations for all taste qualities and higher correlation levels between subjective taste sensations and EGM thresholds than the group with BM symptoms (n = 20). The patterns of taste disorders also showed more significant associations with the levels of subjective taste sensations in the patients without BM symptoms compared with those with BM symptoms. In conclusion, patients with taste disorders without BM symptoms had more severe taste disturbances than those with BM symptoms. The pathophysiology of taste disturbances differs according to the presence or absence of BM symptoms. [ABSTRACT FROM AUTHOR]

Evaluate the effects of addition of ascorbic acid (AscA) to experimentally fabricated calcium silicate cement on setting time, flowability, and wash-out resistance properties. Experimental calcium silicate (CS) cement clinkers were synthesized via a solid state reaction at 1,450 ℃ for 15 min followed by quenching at 1,250 ℃, and the clinkers were pulverized by vibration milling and jet milling, The starting materials for calcium silicate clinker were CaCO 3 , SiO 2 , Al 2 O 3 , MgO, K 2 CO 3 , Na 2 CO 3 (LSF: 88.98, 98.19, and 108.43). After characterizing the obtained product using XRD/XRF/SEM/TEM/FT-IR, we chose the composition having a high percentage of tricalcium silicate phase and low free CaO content (LSH 98.19) as the main composition. Addition of ZrO 2 (20 wt%) to the jet-milled CS powder, and second addition of CaSO 4 ·½H 2 O (5 wt%) were done. AscA was incorporated into the mixing solution in various concentrations. The Gilmore setting time, flow test (ISO and LVDT method), penetration resistance, compressive strength, and wash-out resistance ('water jet' through 18 G needle for 5 s to 400 rpm-spinning 150 second-set CS cement sample with a flow rate of 60 mL/min, '3D scanning', and 'eroded volume calculation' with Catia V5 Program) were evaluated. MTT assay and antimicrobial tests were performed. AscA incorporation into experimentally fabricated CS cement reduces the setting time (p<0.01, r = -0.935), and affected the flowability, wash-out resistance, and compressive strength depending on the concentration (Table 1, Figure 1). AscA addition in experimental CS cement showed a statistically insignificant increase in cell viability (CV) at 25% extract concentration compared to the without addition group (p=0.064). However, at the higher extract concentration, there was no significant difference in CV between test groups. Antibacterial activity against E. Coli. and E. faecalis showed no meaningful difference between with-AscA (0.05 wt%) and without-AscA groups. The AscA incorporation in dental CS cement could be a promising method to improve the setting, physical, handling, and biological properties. [ABSTRACT FROM AUTHOR]

Objective To evaluate treatment outcomes of in situ abdominal aortic reconstruction with cryopreserved arterial allograft (CAA) for patients with abdominal aortic infection. Materials and methods A retrospective review of prospectively collected data was conducted of patients who underwent in situ aortic reconstruction using CAA for primary, secondary, or prosthetic infection of the abdominal aorta between May 2006 and July 2015, at a single institution. Clinical presentation, indications for treatment, procedural details, early post-operative mortality and morbidity, late death, and graft related complications during the follow up period were investigated. Patient survival and event free survival (any death or re-operation) were calculated using the Kaplan-Meier method. Results Twenty-five patients (male, n = 20, 80%; mean age, 70.2 ± 8.7 years) underwent in situ abdominal aortic reconstruction (48% aortic, 52% aorto-bi-iliac) with vessel size and ABO matched CAA for treatment of abdominal aortic infection caused by infected abdominal aortic aneurysm ( n = 15), aortic prosthesis infection ( n = 7), aortic reconstruction with concomitant colon resection ( n = 2), and primary suppurative aortitis ( n = 1). The median follow up was 19.1 months (range 1–73 months). There were seven post-operative deaths including two (8%) early (<30 days) and five (20%) late deaths There were three (12%) graft related complications including thrombotic occlusion of the CAA, aneurysmal dilatation, and aorto-enteric fistula. Three years after CAA implantation, patient survival was 74% and the event free survival was 58%. Conclusions It is believed that in situ abdominal aortic reconstruction with CAA is a useful option for treating primary, secondary, or prosthetic infection of the abdominal aorta. [ABSTRACT FROM AUTHOR]

Hydrologic modeling requires the handling of a wide range of highly nonlinear processes from the scale of a hill slope to the continental scale, and thus the computational efficiency of the model becomes a critical issue for water resource management. This work is aimed at implementing and evaluating a flexible parallel computing framework for hydrologic simulations by applying OpenMP in the HydroGeoSphere (HGS) model. HGS is a 3D control-volume finite element model that solves the nonlinear coupled equations describing surface–subsurface water flow, solute migration and energy transport. The computing efficiency of HGS is improved by three parallel computing schemes: 1) parallelization of Jacobian matrix assembly, 2) multi-block node reordering for performing LU solve efficiently, and 3) parameter privatization for reducing memory access latency. Regarding to the accuracy and consistency of the simulation solutions obtained with parallel computing, differences in the solutions are entirely due to use of a finite linear solver iteration tolerance, which produces slightly different solutions which satisfy the convergence tolerance. The maximum difference in the head solution between the serial and parallel simulations is less than 10 −3 m, using typical convergence tolerances. Using the parallel schemes developed in this work, three key achievements can be summarized: (1) parallelization of a physically-based hydrologic simulator can be performed in a manner that allows the same code to be executed on various shared memory platforms with minimal maintenance; (2) a general, flexible and robust parallel iterative sparse-matrix solver can be implemented in a wide range of numerical models employing either structured or unstructured mesh; and (3) the methodology is flexible, especially for the efficient construction of the coefficient and Jacobian matrices, compared to other parallelized hydrologic models which use parallel library packages. [ABSTRACT FROM AUTHOR]

Highlights: [•] A numerical model for NAPL-involved Compound Specific Isotope Analysis is presented. [•] The model was verified against various conditions necessary for Compound Specific Isotope Analysis. [•] The model is capable of simulating various types of NAPL-involved isotope models with complex conditions. [•] Isotope signatures can be significantly different when considering multiphase flow within the contaminant source zone. [ABSTRACT FROM AUTHOR]

Abstract: The salinity of groundwater increases with depth in the Canadian Shield (up to 1.3kg/L of density). The existence of brine can be critically important for the safe geologic disposal of radioactive wastes, as dense brine can significantly retard the upward migration of radionuclides released from repositories. Static and flushing conditions of the deep brine are analyzed using a U-tube analogy model. Velocity reduction due to the presence of dense brine is derived under flushing conditions. A set of illustrative numerical simulations in a two-dimensional cross section is presented to demonstrate that dense brine can significantly influence regional groundwater flow patterns in a shield environment. It is implied from the results that (1) the existence of Shield brine can be an indicator of a hydrogeologically stable environment, (2) activities near ground surface may not perturb the stable groundwater environment in the deep brine region, and thus, (3) the deep brine region can be considered as a candidate geologic site for the safe disposal of waste. In addition to brine, other issues associated with long-term waste disposal, such as geological, glacial and seismic events, may need to be considered for the safe storage of spent nuclear fuel in a shield environment. [Copyright &y& Elsevier]

Abstract: In general, the accuracy of numerical simulations is determined by spatial and temporal discretization levels. In fractured porous media, the time step size is a key factor in controlling the solution accuracy for a given spatial discretization. If the time step size is restricted by the relatively rapid responses in the fracture domain to maintain an acceptable level of accuracy in the entire simulation domain, the matrix tends to be temporally over-discretized. Implicit sub-time stepping applies smaller sub-time steps only to the sub-domain where the accuracy requirements are less tolerant and is most suitable for problems where the response is high in only a small portion of the domain, such as within and near the fractures in fractured porous media. It is demonstrated with illustrative examples that implicit sub-time stepping can significantly improve the simulation efficiency with minimal loss in accuracy when simulating flow and transport in fractured porous media. The methodology is successfully applied to density-dependent flow and transport simulations in a Canadian Shield environment, where the flow and transport is dominated by discrete, highly conductive fracture zones. [Copyright &y& Elsevier]

Abstract: The association between an abdominal aortic aneurysm (AAA) and tuberous sclerosis (TS) is rare. An 8-month-old girl presented with a seizure, and the clinical evaluation revealed TS. An abdominal evaluation showed a 3-cm infrarenal AAA. A normal diameter of infrarenal aorta for an 8-month-old girl is about 6mm. The patient underwent an open repair with a polytetrafluoroethylene (PTFE) prosthesis. The pathology showed a loss of elastin fibres in the media of the aorta. The graft was patent on computed tomography (CT) angiography, performed 4 months after the operation. However, the patient died of complications related to seizures 5 years after the surgery. The graft remained patent until the time of death. [Copyright &y& Elsevier]

This study evaluated the accuracy of cefotetan susceptibility determination using the MicroScan WalkAway system for AmpC-producing Klebsiella pneumoniae. In total, 57 K. pneumoniae isolates that showed a D-shape flattening in a double-disk synergy test were studied. Cefotetan MICs were determined by the agar dilution method. The blaDHA gene was detected in all 57 isolates, one of which co-harboured blaCMY-1. According to the MicroScan system, 28 isolates were susceptible, 18 were intermediately-resistant, and 11 were resistant to cefotetan. Compared with the agar dilution method, very major, minor and major error rates were 28.1% (16/57), 47.4% (27/57) and 1.8% (1/57), respectively. [ABSTRACT FROM AUTHOR]

Abstract: This study systemically investigates the retardation of electrical-stress-induced degradation in Ge2Sb2Te5 (GST) by modifying its material properties through doping. The effects of doping on the electromigration and void formation in molten GST are explored by studying the model of a large and symmetric line-shaped GST cell doped with nitrogen, oxygen and bismuth, using high-amplitude electrical pulse stress. The electromigration rate, which is represented by the product of the diffusion coefficient and effective charge number (DZ *), and the amount of void formation in doped GST are quantified and compared with undoped GST. The DZ * and void area in Bi-doped GST increased by ∼10% compared with those in undoped GST; these values decreased by 30% and 45% in the O- and N-doped GST, respectively. The results suggest that the interstitial-type dopant could suppress the electromigration rate and void formation by decreasing the free volume; however, the substitutional-type dopant could not. The change in the free volume of molten GST due to dopants led to the change in the electromigration rate and the area of void formation. Understanding how the atomic-bonding type of dopants affects the degradation phenomena helps in designing phase-change material that is more stable against device failures. [Copyright &y& Elsevier]

Abstract: Mycophenolic acid (MPA) is an immunosuppressive agent that is widely used in clinical therapy, including pancreas and islet transplantation. Previously, we showed that MPA induces significant apoptosis of insulin-secreting cells by downregulating RhoGDI-α and increasing JNK expression. In this study, we investigated Rac1 directly associated with RhoGDI-α during MPA-induced apoptosis in INS-1E cells (an insulin-secreting cell line). Cells were treated with MPA for 24 and 36 hours. Immunoprecipitation was used to examine physical interactions between RhoGDI-α and Rac1. Activation and immunoprecipitation assays showed expressions of Rac1 and RhoGDI-α to be directly correlated. Rac1 binding to RhoGDI-α decreased after MPA treatment, and Rac1 was induced and subsequently activated by MPA. We concluded that this novel RhoGDI-α/Rac1/JNK pathway induced apoptosis of transplanted islet cells after MPA treatment. [Copyright &y& Elsevier]

Abstract: Optimal immunosuppression after pancreas islet transplantation has not yet been established to achieve long-term graft survival. Mycophenolic acid (MPA) is widely used as an immunosuppressive drug after transplantation including among recipients of pancreas islet cells. Previously, we reported MPA-induced islet apoptosis in the HIT-T15 cell line. In this study, we confirmed the effects of MPA on cell death and its potential implications on the mitogen-activated protein kinase (MAPK) family expression levels in primary isolated rat islets. Lewis islets isolated by collagenase digestion were purified by the density gradient method. Cell death was analyzed by methylthiazoletetrazolium assay. Activation of MAPK kinase 4 (MKK4), c-jun N-terminal protein kinase (JNK), p38 MAPK, and caspase-3 cleavage was examined by Western blot analyses. MPA treatments (>25 μmol/L) increased cell death significantly at 24 hours and in a dose-dependent manner activated MKK4, JNK, and p38 MAPK at 20 hours. Caspase-3 cleavage was also increased by MPA treatment. These results suggested that MPA induced significant cell death among primary isolated rat islets by activation of MKK4, JNK, and p38 MAPK, as well as caspase-3 cleavage. [Copyright &y& Elsevier]

Abstract: Background: Urinary tract infections (UTIs) are the most common infectious complication in kidney transplant recipients (KTRs). The aim of this study to investigate the risk factors for and causative organisms of UTI as well as to evaluate the impact these diseases on allograft function in KTRs. Methods: We analyzed patients who underwent kidney transplantation (KT) between January 2000 and December 2010. Among a total of 344 KTRs, 50 (14.5%) patients experienced 106 UTI episodes during a mean follow-up of 35.9 ± 26.0 months. Twenty three patients experiencing recurrent UTI were compared with 27 nonrecurrent UTI patients and with 50 non-UTI patients matched for age, gender, and transplantation date. Results: The number of patients with renal calculi, diabetes, or prior dialysis was significantly greater among the UTI group compared with control subjects. In addition, the number of patients with renal calculi was significantly higher among the recurrent compared with the nonrecurrent cohort (43.5 vs 7.4%; P = .003). The most common causative organism was Escherichia coli (64.1%), followed by Enterococcus species (20.5%). Higher rates of antibiotic resistance, especially Extended Spectrum Beta-Lactamasc (ESBL) production, were observed among the recurrent compared with the nonrecurrent group (53.1 vs 0%; P = .013). The rate of decline of estimated glomerular filtration rate was significantly faster in the UTI than the non-UTI group, whereas it did not differ between the recurrent and nonrecurrent group. Conclusions: Adequate treatment of an initial UTI to prevent as recurrent infection and prolong graft longevity is especially reasonable for KTRs with renal calculi or in cases of antibiotic-resistant microorganisms. [Copyright &y& Elsevier]

Abstract: In islet transplantation, encapsulation of immunoisolated islets may provide a way to protect the graft from immune attacks with no immunosuppression. To develop an immunodelusive immunoisolated bioartificial pancreas (BAP), chondrocyte sheets were prepared by cell sheet engineering. We made an immunoisolated BAP encapsulated with rodent-derived chondrocyte sheets and then evaluated its function. Sprague-Dawley rats were used as the source of auricular cartilage and chondrocytes were maintained and expanded by passages. Lewis rats were prepared for islet isolation. A 3-dimensional chondrocyte sheeting immunodelusive immunoisolated BAP (CSI-BAP) was created by multi-layering and unifying the chondrocyte sheets. Subsequently, islets were embedded between each multi-layer sheet. To evaluate the function of the CSI-BAP, a glucose challenge test was performed and secretion of insulin in the culture medium was measured by an enzyme-linked immunosorbent assay. When observed by phase-contrast microscopy, the CSI-BAP maintained close connections between chondrocyte sheets. Islets in the CSI-BAP maintained viability at day 10 and showed good insulin secretion, as revealed by a prompt reaction to increased concentrations of glucose at days 5 and 10. In long-term culture, the CSI-BAP maintained its ability to secrete insulin for 8 weeks. This BAP technology could be an important tool for successful islet transplantation without immunosuppressive drugs. [Copyright &y& Elsevier]

Abstract: Porcine-specific obstacles in islet isolation frequently result from the low purity or contamination with exocrine tissues. We implemented a new technique involving as capsulation of islets with excess exocrine tissue as a beneficial material to address those difficulties. Pig islets were hand-picked as high purity (HI) or low purity (LO) islets containing significant amounts of exocrine tissue. We performed static (ST) or shaking (SK) cultures of HI and LO islets. Islet function was examined after 24 hours by a glucose challenge test. Insulin secretion into the culture media was continuously measured using ELISA during a 6-day culture period. Islet function after 24 hours exhibited better maintenance under SK than ST culture as assessed by a stimulation index. The ideal islet morphology was seen in LO islets at 3 days of SK culture with typical islet shapes of a smooth surface and a spherical configuration. In contrast, typical islet morphology was not observed in HI islets under SK culture; maintenance of typical spherical appearances was difficult. Insulin secretion from LO islets under SK culture was higher than under other conditions during the 6-day period. Under SK culture conditions, exocrine-encapsulated LO islets showed enhanced islet function by condensing loose islet aggregates into firm spheroids with native exocrine tissues as a natural scaffold. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to identify whether the serum interferon-gamma (IFNγ), a Th1 cytokine, or soluble CD30 (sCD30), a marker for activation of Th2 cytokine-producing T cells, predict acute cellular rejection episodes among liver graft patients. Pretransplant and posttransplant sera from 32 living donor liver transplant recipients obtained on days 1, 3, and 7 after surgery were tested for serum IFNγ and sCD30 concentrations using commercial enzyme-linked immunosorbent assay kits. Recipients with an acute rejection episode (ARE) (n = 14) displayed significantly higher IFNγ concentrations pretransplant than did the patients with no ARE (n = 18) (P < .05). The pretransplant serum levels of sCD30 were not different between the non-ARE and ARE groups. However, in comparison with the non-ARE group, who showed steadily decreasing serum sCD30 levels after transplantation, 12 among the 14 patients in the ARE group showed increasing sCD30 levels from day 1 to day 3 after transplantation (P < .05). These results suggest that the sCD30 increment during the early period after liver transplantation affects the immune response of rejection. This observation emphasizes the clinical relevance of serum sCD30, in addition to serum IFNγ, as predictive markers for acute liver graft rejection. [Copyright &y& Elsevier]