139 research outputs found
Effect of Dy substitution in the giant magnetocaloric properties of HoB
Recently, a massive magnetocaloric effect near the liquefaction temperature
of hydrogen has been reported in the ferromagnetic material HoB. Here we
investigate the effects of Dy substitution in the magnetocaloric properties of
HoDyB alloys ( = 0, 0.3, 0.5, 0.7, 1.0). We
find that the Curie temperature () gradually increases upon
Dy substitution, while the magnitude of the magnetic entropy change || at = decreases from 0.35 to 0.15
J cm K for a field change of 5 T. Due to the presence of two
magnetic transitions in these alloys, despite the change in the peak magnitude
of ||, the refrigerant capacity () and
refrigerant cooling power () remains almost constant in all
doping range, which as large as 5.5 J cm and 7.0 J cm for a field
change of 5 T. These results imply that this series of alloys could be an
exciting candidate for magnetic refrigeration in the temperature range between
10-50 K.Comment: 19 pages, 5 figures, 2 table
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Short-term impact of aged garlic extract on endothelial function in diabetes: A randomized, double-blind, placebo-controlled trial.
Impaired endothelial function portends an increased risk of cardiovascular disease. Vascular oxidative stress and systemic inflammation play a critical role in the pathogenesis and progression of vascular disease. Aged garlic extract (AGE) may improve impaired vascular endothelial function, while decreasing the progression of atherosclerotic plaque. We hypothesized that AGE may improve endothelial function, and in this study, we examined this hypothesis to determine whether this can be achieved over a period of 3 months, measured by the cardio-ankle vascular index (CAVI), by reducing intracellular oxidant stress and stimulating nitric oxide generation in endothelial cells. We conducted a double-blinded placebo controlled, randomized clinical trial to investigate the effects of AGE on CAVI in subjects with type 2 diabetes mellitus. A total of 65 individuals (38 men and 27 women) with a mean age of 58.8±11.1 years were enrolled and randomized to the AGE or placebo group in a double-blind placebo controlled trial. An ANOVA model with treatment as the main effect was used to compare changes in CAVI from baseline to follow-up between groups. The primary objective of this study was reduction in CAVI over a 3-month period. In the AGE group, CAVI was reduced on average by 0.71±1.27 vs. a mean reduction of 0.13±0.94 in the placebo group (P=0.04). On the whole, this study demonstrates that AGE has a positive impact on endothelial function in patients with T2DM and may play a role in the primary prevention of cardiovascular disease
Serum interleukin (IL)-10 and IL-12 levels and IL28B gene polymorphisms: pretreatment prediction of treatment failure in chronic hepatitis C
Background: Both IL28B gene polymorphisms and serum levels of interleukin (IL)-10, IL-12p40 and IL-18 have been reported to affect the outcome of natural and pegylated interferon and ribavirin-treated HCV infection. Methods: To clarify their association and predictive value in treatment outcome of genotype 1 HCV-infected patients, we measured pretreatment serum IL-10, IL-12p40 and IL-18 levels using multiplex assays and determined IL28B gene polymorphisms (rs 8099917) in 52 cases with chronic hepatitis C. Results: High baseline levels of IL-10 (P<0.001) and low levels of IL-12p40 (P<0.001) were significantly associated with a non-virological response (NVR) in our cohort. The IL28B polymorphism was tested and TT, TG or GG genotypes were found in 60%, 38% and 2% of patients, respectively, with corresponding NVR rates of 10%, 60% and 100% (P<0.001). Serum cytokine levels were significantly correlated with IL28B gene polymorphisms. When serum IL-10 levels were stratified at 5.0 pg/ml, NVR rates were 50% versus 0% (P=0.004) for the IT genotype and 87% versus 0% (P=0.001) for the TG or GG genotypes. Similarly, low IL-12p40 levels were associated with an NVR in patients with TG or GG genotypes (P=0.006). In multivariate analysis, high IL-10, low IL-12p40 and IL28B TG or GG genotypes were independently associated with an NVR. Conclusions: Serum IL-10 and IL-12p40 levels in combination with IL28B genotype, especially G-allele carriage, are strong predictive markers of an NVR to HCV treatment with pegylated interferon and ribavirin.ArticleANTIVIRAL THERAPY. 16(7):1073-1080 (2011)journal articl
Serum chemokine levels are associated with the outcome of pegylated interferon and ribavirin therapy in patients with chronic hepatitis C
Aim: Serum chemokine levels and amino acid substitutions in the interferon-sensitivity determining region (ISDR) and core region have been associated with treatment outcome of pegylated interferon and ribavirin therapy in genotype 1 hepatitis C virus (HCV)-infected patients. The present study was conducted to clarify the association between serum chemokines and treatment outcome in patients with chronic HCV-1 infection in a Japanese cohort. Methods: A total of six serum chemokines were quantified before, during and after pegylated interferon and ribavirin treatment in 79 genotype 1 chronic HCV patients using a multiple bead array system. Viral ISDR and core region variants were determined by direct sequencing. Results: The baseline serum levels of eotaxin, IP-10 and RANTES were significantly higher in chronic HCV patients than in controls. High levels of eotaxin and macrophage inflammatory protein (MIP)-1 beta before therapy and more than two mutations in the ISDR were associated with a sustained virological response, and patients with more than two mutations in the ISDR also had significantly higher MIP-1 beta levels. Receiver-operator curve analysis showed a 77% sensitivity and 73% specificity for predicting an SVR using MIP-1 beta values. Conclusion: Serum MIP-1 beta levels may predict the response to HCV treatment with pegylated interferon and ribavirin and are associated with amino acid substitutions in the ISDR.ArticleHEPATOLOGY RESEARCH. 41(6):587-593 (2011)journal articl
Association of Serum Cytokine Levels With Treatment Response to Pegylated Interferon and Ribavirin Therapy in Genotype 1 Chronic Hepatitis C Patients
Methods. We quantified a total of 8 serum cytokines before, during, and after treatment in 79 genotype 1 chronic HCV patients. Viral ISDR and core region variants were determined by direct sequencing. Results. High levels of interleukin (IL)-12 and IL-18 and more than 2 mutations in the ISDR were associated with a sustained virological response (SVR). Conversely, high baseline IL-10 levels and glutamine at amino acid 70 of the HCV core protein (Gln70) were significantly associated with a nonresponse to treatment, and patients with Gln70 had significantly higher IL-10 levels. In multivariate analysis, low IL-10, high IL-12, and high IL-18 levels were independently associated with an SVR. These 3 cytokine levels were decreased from baseline levels 4 weeks into treatment and remained low in patients with an SVR. Conclusion. Serum IL-10, IL-12, and IL-18 levels are predictive of the response to HCV treatment with pegylated interferon and ribavirin and are associated with amino acid substitutions in the ISDR and core region.ArticleJOURNAL OF INFECTIOUS DISEASES. 203(8):1087-1095 (2011)journal articl
Comparison of carbon dioxide and air insufflation use by non-expert endoscopists during endoscopic retrograde cholangiopancreatography
Background: Endoscopic retrograde cholangiopancreatography (ERCP) is subject to several complications that include a lengthy procedure time, technical difficulty, and active bowel movement induced by air insufflation. In ERCP carried out by non-expert endoscopists who are prone to excessive luminal insufflation, insufflation with carbon dioxide (CO2) may provide better and safer outcomes. We aimed to assess the efficacy and safety of CO2 insufflation during ERCP by non-expert endoscopists. Methods: This study included 208 consecutive patients who received ERCP, excluding those in poor general health or with obstructive lung disease. The first operator for each patient was a non-expert endoscopist having done 50 or fewer ERCP procedures. Primary outcomes were the changes in cardiopulmonary state during ERCP. Secondary outcomes were ERCP complications. We designed a single-center, randomized, prospective, double-blind, controlled trial with CO2 and air insufflation during ERCP. Results: CO2 insufflation did not affect overall procedure progression or results. A positive correlation was observed between procedure time and change in maximal systolic blood pressure from baseline among patients in the air insufflation group, but not in the CO2 insufflation group (correlation coefficient 0.408 vs 0.114, change in the maximal systolic blood pressure from baseline +4.2 vs+1.2mmHg/10min). This was consistent with our findings in patients treated by the first operator alone. The occurrence rate of post-ERCP pancreatitis tended to be lower in the CO2 group than the air group (4/102 [3.9%]vs 0/106 [0%], P=0.056). Conclusions: CO2 insufflation during ERCP by non-expert endoscopists is recommended from the standpoints of efficacy and safety.ArticleDIGESTIVE ENDOSCOPY. 25(2):189-196 (2013)journal articl
Risk factors for pancreatic stone formation in autoimmune pancreatitis over a long-term course
Autoimmune pancreatitis (AIP) has the potential to progress to a chronic state that forms pancreatic stones. The aim of this study was to clarify the risk factors underlying pancreatic stone formation in AIP. Sixty-nine patients with AIP who had been followed for at least 3 years were enrolled for evaluation of clinical and laboratory factors as well as computed tomography and endoscopic retrograde cholangiopancreatography findings. During the course of this study, increased or de novo stone formation was seen in 28 patients, who were defined as the stone-forming group. No stones were observed in 32 patients, who were defined as the non-stone-forming group. Nine patients who had stones at diagnosis but showed no change during the course of this study were excluded from our cohort. Univariate analysis revealed no significant differences in clinical or laboratory factors associated with AIP-specific inflammation between the two groups. However, pancreatic head swelling (P = 0.006) and narrowing of both Wirsung's and Santorini's ducts in the pancreatic head region (P = 0.010) were significantly more frequent in the stone-forming group. Furthermore, multivariate analysis identified Wirsung and Santorini duct narrowing at diagnosis as a significant independent risk factor for pancreatic stone formation (OR 4.4, P = 0.019). A primary risk factor for pancreatic stone formation in AIP was narrowing of both Wirsung's and Santorini's ducts, which most presumably led to pancreatic juice stasis and stone development.ArticleJOURNAL OF GASTROENTEROLOGY. 47(5):553-560 (2012)journal articl
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