Indoxyl sulphate-TNFα axis mediates uremic encephalopathy in rodent acute kidney injury.

Acute kidney injury (AKI) is often accompanied by uremic encephalopathy resulting from accumulation of uremic toxins in brain possibly due to impaired blood-brain barrier (BBB) function. Anionic uremic toxins are substrates or inhibitors of organic anionic transporters (OATs). In this study we investigated the CNS behaviors and expression/function of BBB OAT3 in AKI rats and mice, which received intraperitoneal injection of cisplatin 8 and 20 mg/kg, respectively. We showed that cisplatin treatment significantly inhibited the expressions of OAT3, synaptophysin and microtubule-associated protein 2 (MAP2), impaired locomotor and exploration activities, and increased accumulation of uremic toxins in the brain of AKI rats and mice. In vitro studies showed that uremic toxins neither alter OAT3 expression in human cerebral microvascular endothelial cells, nor synaptophysin and MAP2 expressions in human neuroblastoma (SH-SY5Y) cells. In contrast, tumour necrosis factor alpha (TNFα) and the conditioned medium (CM) from RAW264.7 cells treated with indoxyl sulfate (IS) significantly impaired OAT3 expression. TNFα and CM from IS-treated BV-2 cells also inhibited synaptophysin and MAP2 expressions in SH-SY5Y cells. The alterations caused by TNFα and CMs in vitro, and by AKI and TNFα in vivo were abolished by infliximab, a monoclonal antibody designed to intercept and neutralize TNFα, suggesting that AKI impaired the expressions of OAT3, synaptophysin and MAP2 in the brain via IS-induced TNFα release from macrophages or microglia (termed as IS-TNFα axis). Treatment of mice with TNFα (0.5 mg·kg-1·d-1, i.p. for 3 days) significantly increased p-p65 expression and reduced the expressions of Nrf2 and HO-1. Inhibiting NF-κB pathway, silencing p65, or activating Nrf2 and HO-1 obviously attenuated TNFα-induced downregulation of OAT3, synaptophysin and MAP2 expressions. Significantly increased p-p65 and decreased Nrf2 and HO-1 protein levels were also detected in brain of AKI mice and rats. We conclude that AKI inhibits the expressions of OAT3, synaptophysin and MAP2 due to IS-induced TNFα release from macrophages or microglia. TNFα impairs the expressions of OAT3, synaptophysin and MAP2 partly via activating NF-κB pathway and inhibiting Nrf2-HO-1 pathway.

[Comparison of the shear bond strength by using nano silica sol to zirconia basement and veneer porcelain].

PURPOSE: To investigate the feasibility of using sol gel technique to produce thin layer nano silicon dioxide on zirconia ceramic surface and the effect of improving shear bond strength between zirconia and veneer porcelain. METHODS: The presintered zirconia specimen was cut into a rectangle block piece (15 mm×10 mm×2.5 mm), a total of 40 pieces were obtained and divided into 4 groups, each group had 10 pieces. Four different treatments were used in each group respectively. Pieces in group A (control group) were only sintered at 1450°C to crystallization; pieces in group B underwent 30% nano silica sol infiltration first and then were sintered at 1450°C to crystallization; piece in group C underwent crystallization first at 1450°C, then 30% nano silica sol infiltration and were sintered at 1450°C again; pieces in group D was coated by nano silica sol and then sintered at 1450°C to crystallization; ten rectangle block pieces (12 mm×8 mm×2 mm) in group E were made. Cylinder veneers 5 mm in diameter and 4 mm in height were produced in each group and the shear bond strength was tested. Data were statistically analyzed by SPSS 19.0 software package. RESULTS: The shear bond strength of the 5 group specimens were: (28.12±2.95) MPa in group A, (31.09±3.94) MPa in group B, (25.60±2.45) MPa in group C, (31.75±4.90) MPa in group D, (28.67±3.95) MPa in group E, respectively. Significant differences existed between the 5 groups, and group C had significant difference compared with group B and D. CONCLUSIONS：① Use of nano silicon sol gel on presintered zirconia surface to make thin layer of nano silicon dioxide can improve the shear bond strength between zirconia and veneer; ②Using nano silicon sol gel on crystallization zirconia surface to make thin layer of nano silicon dioxide will decrease the shear bond strength between zirconia and veneer; ③ Zirconia veneer bilayer ceramic has the same shear bond strength with porcelain fused to Ni Cr alloy; ④Use of sol gel technique to produce thin layer nano silicon dioxide on zirconia ceramic surface is feasible and can improve shear bond strength between zirconia and veneer porcelain.

Association of proton pump inhibitors with the occurrence of gut-derived bacteraemia in patients with haematological malignancy after chemotherapy.

BACKGROUND: Gut-derived bacteraemia is a major complication in patients with haematological malignancy after chemotherapy. OBJECTIVE: Our study aimed to investigate the role of proton pump inhibitors (PPIs) in the occurrence of gut-derived bacteraemia. METHODS: We compared data from 92 hospitalized haematological malignancy patients after chemotherapy with gut-derived bacteraemia, collected from January 2009 to July 2015, with those of 92 contemporaneous, hospitalized haematological malignancy patients without bacteraemia. We evaluated PPIs use and analysed the effects of covariates. RESULTS: Patients with gut-derived bacteraemia had a significantly higher incidence of PPIs use (69.6%) than that of controls (47.8%). Of the patients with gut-derived bacteraemia, only 44.6% had a documented indication for PPIs therapy. The antibacterial prophylaxis rate was 38.0% in the bacteraemia group and 58.7% in the non-antibacterial group. Based on multivariable logistic regression analysis, only PPIs use (P = 0.00, odds ratio (OR) = 0.546) was found to be associated with the risk of bacteraemia whereas antibacterial prophylaxis (P = 0.00, OR = 0.652) was protective. There were no significant differences in demographics, malignancy status, length of neutropenia, complications, or steroid use between the gut-derived bacteraemia and control group. CONCLUSIONS: This study suggests a potential association between PPIs use and development of gut-derived bacteraemia in haematological malignancy patients after chemotherapy.

Hyperbranched polycoumarates with photofunctional multiple shape memory.

In good shape: The films of hyperbranched polycoumarate derivatives can undergo a reversible [2+2] cycloaddition under irradiation of UV light and behave like photomechanical elastomers. From a predetermined original shape A the photonically and thermally memorized shapes B and C were obtained. The original shape was recovered by photoirradiation (see picture; Tg =glass transition temperature).

[Protective effects of sodium nitrite preconditioning against alcohol-induced acute liver injury in mice].

The purpose of the present study was to investigate the effect of sodium nitrite (SN) on alcohol-induced acute liver injury in mice. Forty male C57bL/6 mice were randomly divided into 4 groups. Acute alcohol-induced liver injury group were injected intraperitoneal (ip) with alcohol (4.5 g/kg); SN preconditioning group were pretreated with SN (16 mg/kg, ip) for 12 h, and received alcohol (4.5 g/kg, ip) injection; Control and SN groups were treated with saline and SN, respectively. After the treatments, liver index (liver/body weight ratio) was determined. Colorimetric technique was performed to measure the serum alanine transaminase (ALT), aspartate transaminase (AST), liver superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) activities, as well as malondialdehyde (MDA) content. The pathological index of liver tissue was assayed by HE and TUNEL fluorometric staining. Using Western blot and immunohistochemistry staining, the expression of hypoxia-inducible factor-1α (HIF-1α) protein was detected. The results showed that, compared with acute alcohol-induced liver injury group, pretreatment with low doses of SN decreased liver index and serum levels of ALT and AST, weakened acute alcohol-induced hepatocyte necrosis, improved pathological changes in liver tissue, increased live tissue SOD, GSH-Px and CAT activities, reduced MDA content and apoptosis index of hepatocytes, and up-regulated HIF-1α protein level in liver tissue. These results suggest that the pretreatment of SN can protect hepatocytes against alcohol-induced acute injury, and the protective mechanism involves inhibition of oxidative stress and up-regulation of HIF-1α protein level.

[Sodium nitrite improves epithelial-mesenchymal transition of hepatoma cells in mice bearing H22].

This study is to report the determination of the effect of sodium nitrite induced oxygen species (ROS) on the epithelial-mesenchymal transition in hepatoma cells in mice bearing H22 and investigation of its role in hypoxia-inducible factor 1alpha (HIF-1alpha) in this process. Mice hepatocarcinoma cell line H22 was inoculated subcutaneously into right axillary of sixty male Kunming mice and then randomly divided into four groups: control group; low-dose sodium nitrite group (10 mg x kg(-1)), medium-dose sodium nitrite group (20 mg x kg(-1)) and high-dose sodium nitrite group (30 mg x kg(-1)). Sodium nitrite group was given (ig) sodium nitrite with 10-30 mg x kg(-1) x d(-1) for 21 days. Compared with control group, there was no obvious difference between the two groups in the volume or weight of xenografts, but in sodium nitrite treatment group, the activity of SOD and CAT decreased and contents of MDA or nitrite increased in tumor tissue of mice bearing H22; epithelial-mesenchymal transition (EMT) of hepatoma cells was induced, the EMT-phenotype tumors displayed a greater degree of local aggressiveness, with dissection through adjacent fascia and skeletal muscle. The increased expression of HIF-la and vimentin and declination of E-cadherin were confirmed by immunohistochemistry and Western blotting. These data indicate sodium nitrite treatment could improve the epithelial-mesenchymal transition of xenografts in mice bearing H22, which might relate to the fact that ROS mediated signal pathway increased the expression of HIF-1alpha.

Effects of background, direction and intensity of ambient light, measuring position, and adjacent teeth, on anterior tooth colour measurement in vitro.

OBJECTIVE: to investigate the effects of different background colours (black, white or pink), direction and intensity of ambient light, measuring position, and the adjacent teeth, on the in vitro colour measurement of maxillary anterior teeth, using the Minolta CR-321 colorimeter. METHODS: ten extracted human maxillary central incisors were selected. A fibre-optic light MI-150 was used as the ambient illuminant. Teeth were irradiated from a 3- or 12-o'clock direction. L*a*b* values of seven sites on the labial surfaces were obtained by means of the Minolta CR-321 colorimeter, using three background colours, with or without the adjacent teeth. The recorded data were analysed with two-tailed Student t tests and analysis of variance (α = 0.05). RESULTS: the ambient light did not affect the colour measurement of anterior teeth, regardless of the presence or absence of the adjacent teeth. There were no statistically significant differences in L*a*b* values at the same position under different background colours, except ΔE12 (colour difference between site 1 and site 2) between black and white backgrounds. ΔE12 (under black background), ΔE13 and ΔE15 were greater than 1.5, while the others were lower than 1.5. CONCLUSION: the background, ambient light and the presence of adjacent teeth did not affect the colour measurement of anterior teeth using the Minolta CR-321 colorimeter in vitro. The inherent disadvantages of using the naked eye during clinical visual shade assessment may be overcome by the colorimeter.

[Influence of MgO and TiO2 on mechanical properties of zirconia toughened alumina ceramics formed by gel-casting technique].

OBJECTIVE: The objective of this study is to investigate the influence of mechanical properties and sintering performance by adding 5% weight percentage aids to nano-compound zirconia toughened alumina (ZTA) ceramics. METHODS: Micrometer Al2O3 and nanometer ZrO2 (quality ratio 4:1) were used to get 55% volume percentage slurry. Magnesium oxide and titanium oxide were taken as aids which were 5% weight percentage of the Al2O3 and ZrO2 powder. Five groups (number 0, 1, 2, 3, 4 group) were divided according to different proportion of aids. After gel-casting, the porcelain pieces were sintered at 1150, 1200, 1300, 1400, 1450, 1500, 1600 degrees C for 2 hours. Static three-point flexure strength, line shrinkage, relative density were measured and scanning electron microscopy (SEM) was used to observe section. RESULTS: Number 1 (MgO 1%, TiO2 4%) group had the highest bending strength. It was (401.78+/-19.50) MPa after sintering at 1600 degrees C for 2 hours and was higher than 0 group (380.64+/-44.50) MPa. Bending strength became lower than 0 group when MgO was more than 2% or more than that weight percentage of ZTA powder. When MgO content was higher than 2% or more than that weight percentage, there was no difference in relative density raising rate between each sintering assistants groups. When the sintering temperature was higher than 1200 degrees C, all groups showed obvious line-shrinkage and the groups which contained sintering assistants were all was higher than 0 group. CONCLUSION: Adding MgO and TiO2 aids from 1% to 4% weight percentage of ZTA will promote fritting and increase ZTA nano-compound ceramics mechanical properties. Adding 2% MgO aids or more than that weight percent will has no obvious help to increase the relative density raising rate of ZTA nano-compound ceramics and will degrade the mechanical properties of ZTA nano-compound ceramics.

[Influence of ambient light and adjacent tooth in anterior tooth color measurement].

OBJECTIVE: To investigate the influence of different intensity and directions of ambient light and adjacent tooth in anterior tooth color measurement by using colorimeter. METHODS: Fiber lite MI-150 was used as ambient illuminant and it irradiated from three or twelve o'clock direction through 45 degrees angle above. The light magnitude 0, 50, 75, 100, 125, 150 W were applied in this experiment. The values of CIE L* a* b* were measured by Minolta Chroma meter CR-321 colorimeter on the center labial surface of ten extracted human maxillary central incisors with or without adjacent teeth, then those data were analyzed statistically by using SPSS 11.5. RESULTS: Neither different intensities nor different directions of ambient light could influence the results of color measurement by using Minolta Chroma meter CR-321 colorimeter, so did the adjacent teeth whether those were exist or not. CONCLUSION: There is no influence of ambient light and adjacent teeth in the color measurement of anterior teeth under this experiment condition, and Minolta Chroma meter CR-321 colorimeter can be used to measure the color directly aside the chair with light.

Hydrogen-bonded chains in 2,2,2-trichloro-N,N'-bis(4-methoxyphenyl)ethane-1,1-diamine and a three-dimensional hydrogen-bonded framework in 2,2,2-trichloro-N,N'-bis(4-chlorophenyl)ethane-1,1-diamine.

In 2,2,2-trichloro-N,N'-bis(4-methoxyphenyl)ethane-1,1-diamine, C(16)H(17)Cl(3)N(2)O(2), molecules are linked into helical chains by N-H...O hydrogen bonds. Molecules of 2,2,2-trichloro-N,N'-bis(4-chlorophenyl)ethane-1,1-diamine, C(14)H(11)Cl(5)N(2), are connected into a three-dimensional framework by two independent Cl...Cl interactions and one C-H...Cl hydrogen bond.

Two substituted 2-pyrrolin-5-ones: chains built from a single N-H...O hydrogen bond.

In each of methyl 2-methyl-5-oxo-2-pyrroline-3-carboxylate, C(7)H(9)NO(3), and 3-acetyl-2-methyl-2-pyrrolin-5-one, C(7)H(9)NO(2), the pyrrolinone ring is planar. In each structure, molecules are linked into simple chains by way of a single N-H...O hydrogen bond.

[Study on the surface roughness of three dental alloys soaked in artificial saliva].

PURPOSE: The aim of this study was to investigate the corrosion behavior of three metal materials for dental use (Co-Cr alloy, Ni-Cr alloy, titanium) by measurement of their surface roughness after soaked in artificial saliva with two different pH values. METHODS: Standard samples were casted respectively from 3 different alloys and grided into the same roughness .Then the samples were exposed to artificial saliva with two different pH values. After three months,the surface roughness of the samples was tested, and the microstructure of surfaces was studied by metalloscope. The data were analyzed with SPSS11.0 software package for one-way ANOVA and t test. RESULTS: There was significant difference in surface roughness of three alloys after exposed to artificial saliva with pH5.6. The surface roughness values of three alloys were listed as follows: Ni-Cr alloy>Co-Cr alloy >titanium(P<0.01). When exposed to artificial saliva with pH7.0, Ni-Cr alloy was found rougher than Co-Cr alloy and titanium(P<0.01), while there was no significant difference in roughness between Co-Cr alloy and titanium(P>0.05).Ni-Cr alloy and Co-Cr alloy soaked in artificial saliva with pH5.6 were found rougher than the same material in artificial saliva with pH7.0(P<0.01).The microstructure of the samples' surface verified the results. CONCLUSION: Titanium was stable not only in neutral environment but also in acid environment. The corrosion resistance of Co-Cr alloy and Ni-Cr alloy was superior in neutral environment than in acid environment. The corrosion resistance of the three alloys was: Titanium >Co-Cr alloy >Ni-Cr alloy.