Fabrication of submicron alumina ceramics by pulse electric current sintering using M(2+) (M = Mg, Ca, Ni)-doped alumina nanopowders

Dense submicron-grained alumina ceramics were fabricated by pulse electric current sintering (PECS) using M(2+)(M: Mg, Ca, Ni)-doped alumina nanopowders at 1250 degrees C under a uniaxial pressure of 80 MPa. The M(2+)-doped alumina nanopowders (0-0.10 mass%) were prepared through a new sol-gel route using high-purity polyhydroxoaluminum (PHA) and MCl(2) solutions as starting materials. The composite gels obtained were calcined at 900 degrees C and ground by planetary ball milling. The powders were re-calcined at 900 degrees C to increase the content of a-alumina particles, which act as seeding for low-temperature densification. Densification and microstructural development depend on the M(2+) dopant species. Dense alumina ceramics (relative density >= 99.0%) thus obtained had a uniform microstructure composed of fine grains, where the average grain size developed for non-doped, Ni-doped, Mg-doped and Ca-doped samples was 0.67, 0.67, 0.47 and 0.30 mu m, respectively, showing that Ca-doping is the most promising method for tailoring of nanocrystalline alumina ceramics. (c) 2008 Elsevier Ltd and Techna Group S.r.l. All rights reserved.ArticleCERAMICS INTERNATIONAL. 35(5):1845-1850 (2009)journal articl

Densification of rare-earth (Lu, Gd, Nd)-doped alumina nanopowders obtained by a sol-gel route under seeding

Rare-earth (RE: Lu, Gd, Nd, 0.10 mol%)-doped alumina nanopowders were prepared by a new sol-gel route using polyhydroxoaluminum (PHA) and RECl(3) Solutions under alpha-alumina (similar to 75 nm) seeding. Among the rare-earth dopants studied, Lu yields the most suitable nanopowders for low-temperature densification. The 0.10 mol% Lu-doped nanopowders, which were obtained at a calcination temperature of 900 degrees C under 5 mass % alpha-alumina seeding, consisted of similar to 80-nm alpha-alumina particles and gamma-alumina nanoparticles. Using these Lu-doped alumina nanopowders, fully densified alumina ceramics with a uniform microstructure composed of fine grains with an average size of 0.61 mu m could be obtained at 1400 degrees C by pressureless sintering. Clearly, the Lu-doped nanopowders obtained here represent a viable option for fabricating dense, finer-grained alumina ceramics because an undoped sample with 5 mass% seeds gave a microstructure with an average grain size of 1.78 mu m at 1400 degrees C. (C) 2009 Elsevier B.V. All rights reserved.ArticlePOWDER TECHNOLOGY. 193(1):26-31 (2009)journal articl

Prenatal Vitamin E Treatment Improves Lung Growth in Fetal Rats with Congenital Diaphragmatic Hernia

The aim of this study was to test the effects of vitamin E on fetal lung growth in rats with congenital diaphragmatic hernia (CDH). Experimental congenital diaphragmatic hernia (CDH) was induced in rat fetuses by maternal administration of 100 mg nitrofen by gastric gavage on day 9.5 of gestation. Vitamin E was provided at days 16-20 of gestation, at 30 IU/day. Cesarean section was performed at day 21 of gestation. Immunohistochemistry was performed using anti-surfactant protein A (SP-A) and anti-SP-B polyclonal antibodies. RT-PCR evaluated SP-A and SP-B mRNA expressions. The lung weight/body weight ratio in rats with CDH was lower than the control (p<0.01). The number of type II pneumocytes positive for SP-A in untreated CDH rats (n=20) was lower than the control (n=20). The relative amounts of SP-A and SP-B were significantly higher in vitamin Etreated CDH rats (n=20) than untreated CDH rats (p<0.05). Our results suggest that antenatal vitamin E treatment increases the production of surfactant proteins in hypoplastic lung of rats with the CDH

Improvements in liver transplant outcomes in patients with HCV/HIV coinfection after the introduction of direct-acting antiviral therapies

BACKGROUND: In recipients with HCV/HIV coinfection, the impact that the wider use of direct-acting antivirals (DAAs) has had on post-liver transplant (LT) outcomes has not been evaluated. We investigated the impact of DAAs introduction on post-LT outcome in patients with HCV/HIV coinfection. METHODS: Using Organ Procurement and Transplant Network/United Network for Organ Sharing data, we compared post-LT outcomes in patients with HCV and/or HIV pre- and post-DAAs introduction. We categorized these patients into two eras: pre-DAA (2008-2012 [pre-DAA era]) and post-DAA (2014-2019 [post-DAA era]). To study the impact of DAAs introduction, inverse probability of treatment weighting was used to adjust patient characteristics. RESULTS: A total of 17 215 LT recipients were eligible for this study (HCV/HIV [n = 160]; HIV mono-infection [n = 188]; HCV mono-infection [n = 16 867]). HCV/HIV coinfection and HCV mono-infection had a significantly lower hazard of 1- and 3-year graft loss post-DAA, compared pre-DAA (1-year: adjusted hazard ratio [aHR] 0.29, 95% confidence interval (CI) 0.16-0.53 in HIV/HCV, aHR 0.58, 95% CI 0.54-0.63, respectively; 3-year: aHR 0.30, 95% CI 0.14-0.61, aHR 0.64, 95% CI 0.58-0.70, respectively). The hazards of 1- and 3-year graft loss post-DAA in HIV mono-infection were comparable to those in pre-DAA. HCV/HIV coinfection had significantly lower patient mortality post-DAA, compared to pre-DAA (1-year: aHR 0.30, 95% CI 0.17-0.55; 3-year: aHR 0.31, 95% CI 0.15-0.63). CONCLUSIONS: Post-LT outcomes in patients with coinfection significantly improved and became comparable to those with HCV mono-infection after introducing DAA therapy. The introduction of DAAs supports the use of LT in the setting of HCV/HIV coinfection

Short recipient warm ischemia time improves outcomes in deceased donor liver transplantation

While adverse effects of prolonged recipient warm ischemia time (rWIT) in liver transplantation (LT) have been well investigated, few studies have focused on possible positive prognostic effects of short rWIT. We aim to investigate if shortening rWIT can further improve outcomes in donation after brain death liver transplant (DBD-LT). Primary DBD-LT between 2000 and 2019 were retrospectively reviewed. Patients were divided according to rWIT (≤30, 31-40, 41-50, and \u3e50 min). The requirement of intraoperative transfusion, early allograft dysfunction (EAD), and graft survival were compared between the rWIT groups. A total of 1,256 patients of DBD-LTs were eligible. rWIT was ≤30min in 203 patients (15.7%), 31-40min in 465 patients (37.3%), 41-50min in 353 patients (28.1%), and \u3e50min in 240 patients (19.1%). There were significant increasing trends of transfusion requirement (P \u3c 0.001) and increased estimated blood loss (EBL, P \u3c 0.001), and higher lactate level (P \u3c 0.001) with prolongation of rWIT. Multivariable logistic regression demonstrated the lowest risk of EAD in the WIT ≤30min group. After risk adjustment, patients with rWIT ≤30 min showed a significantly lower risk of graft loss at 1 and 5-years, compared to other groups. The positive prognostic impact of rWIT ≤30min was more prominent when cold ischemia time exceeded 6 h. In conclusion, shorter rWIT in DBD-LT provided significantly better post-transplant outcomes

An in vitro system to characterize prostate cancer progression identified signaling required for self-renewal

Mutations in RB and PTEN are linked to castration resistance and poor prognosis in prostate cancer. Identification of genes that are regulated by these tumor suppressors in a context that recapitulates cancer progression may be beneficial for discovering novel therapeutic targets. Although various genetically engineered mice thus far provided tumor models with various pathological stages, they are not ideal for detecting dynamic changes in gene transcription. Additionally, it is difficult to achieve an effect specific to tumor progression via gain of functions of these genes. In this study, we developed an in vitro model to help identify RB- and PTEN-loss signatures during the malignant progression of prostate cancers. Trp53−/−; Rbf/f, Trp53−/−; Ptenf/f, and Trp53−/−; Rbf/f; Ptenf/f prostate epithelial cells were infected with AD-LacZ or AD-Cre. We found that deletion of Rb, Pten or both stimulated prostasphere formation and tumor development in immune-compromised mice. The GO analysis of genes affected by the deletion of Rb or Pten in Trp53−/− prostate epithelial cells identified a number of genes encoding cytokines, chemokines and extracellular matrix remodeling factors, but only few genes related to cell cycle progression. Two genes (Il-6 and Lox) were further analyzed. Blockade of Il-6 signaling and depletion of Lox significantly attenuated prostasphere formation in 3D culture, and in the case of IL-6, strongly suppressed tumor growth in vivo. These findings suggest that our in vitro model may be instrumental in identifying novel therapeutic targets of prostate cancer progression, and further underscore IL-6 and LOX as promising therapeutic targets. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.Embargo Period 12 month

Larval rearing without aeration: a case study of the seven-band grouper Epinephelus septemfasciatus using a wave maker

マハタ種苗生産の初期減耗を軽減する飼育技法開発の基礎知見を得るために，通気による従来の飼育方法（容量1 kL，φ130 ㎝，水深70 ㎝：通気量200 mL/分）と，直径5 ㎝の球を水面で上下させて（1 Hz）水面に波を発生させる造波装置を用いた飼育方法で仔魚の生残を比較した。21 日間の飼育実験での造波装置の生残率は55.5％（n=1）で，対照区のそれ（11.6±14.3％, n=3）よりも顕著に高い値を示した。造波装置による水槽垂直断面の流れを計測したところ，波が水深とともに減衰していくのが確かめられた