Role of renal tubular epithelial cells and macrophages in cisplatin-induced acute renal injury.

Acute kidney injury (AKI) is a clinical syndrome characterized by a sudden and continuous decline in renal function. The drug cisplatin is commonly used as chemotherapy for solid tumors, and cisplatin-induced acute kidney injury (CI-AKI), which is characterized by acute tubular necrosis and inflammation, frequently occurs in tumor patients. Renal tubular epithelial cells (RTECs) are severely damaged early in this process and play an important role in renal tubular injury and the recruitment of immune cells. Macrophages are the most common infiltrating immune cells in the kidney and have a significant impact on CI-AKI and subsequent repair. This article reviews the latest research progress on the effects of RTECs and macrophages on CI-AKI and their interactions in AKI to provide a direction for identifying therapeutic targets for treating AKI.

Role of cyclosporin A in the treatment of kidney disease and nephrotoxicity.

The clinical use of cyclosporin A (CsA) has led to significant advances and achievements in the field of transplantation and immune diseases. However, the nephrotoxicity of CsA is a major concern in current immunosuppression regimens. CsA causes abnormal kidney function while treating kidney disease, causing problems for clinicians and patients. Evidence of CsA nephrotoxicity is almost always present in transplant recipients after long-term CsA administration (up to 10 years), and similar phenomena occur with other calcineurin inhibitors. In this review, we summarize the mechanisms and influencing factors of CsA for the treatment of primary nephrotic syndrome. The mechanisms of CsA nephrotoxicity, clinical-pathological features, diagnosis, prevention strategies, and risk factors are summarized. We discuss the correlates and mechanisms of the switch between kidney disease prevention and nephrotoxicity of CsA to better understand the function of CsA in the kidney and to provide a basis for the prevention and treatment of CsA nephrotoxicity.

OAT3 mediates methotrexate resistance in the treatment of rheumatoid arthritis.

OBJECTIVE: To study whether organic anion transporter 3 (OAT3) is involved in the development of methotrexate (MTX) resistance in the treatment of rheumatoid arthritis. METHODS: The experimental components of the animals were the normal group, collagen-induced arthritis (CIA) model group, and MTX treatment group. MTX-treated rats were divided into the MTX effective group (MTX-E) and the MTX ineffective group (MTX-N). MTX-N receives additional treatment with OAT3 lentivirus injected into the joint cavity. Transient transfection was used to alter the expression of OAT3 in rat fibroblast-like synovial (rat-FLS). RESULTS: The rate of effectiveness of MTX in treating CIA rats was 48.98%. Compared with CIA rats, MTX-E can greatly improve ankle joint synovial hyperplasia and joint damage, but MTX-N has no significant changes. The expression of OAT3 in the synovium of MTX-E was significantly higher than that of MTX-N. The MTX content in the MTX-E synovium was also higher than that in the MTX-N synovium. After injection of OAT3 overexpression lentivirus into the joint cavity of MTX-N, the effective rate of MTX reached 80%. The ankle synovial hyperplasia and joint damage were significantly improved in the overexpression group, and the MTX content was also significantly increased in the synovium. After rat FLS overexpressed OAT3, the inhibitory effect of MTX on rat FLS proliferation activity was significantly enhanced, and the absorption of MTX was also significantly increased, while silencing the expression of rat FLS OAT3 reversed the outcomes. CONCLUSION: OAT3 mediates the formation of MTX resistance and is a potential target for improving MTX resistance.

Lactic Acid Regulation: A Potential Therapeutic Option in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic, persistent autoimmune disease that causes severe joint tissue damage and irreversible disability. Cumulative evidence suggests that patients suffering from RA for long durations are at risk of functional damage to cardiovascular, kidney, lung, and other tissues. This seriously affects the quality of work and life of patients. To date, no clear etiology of RA has been found. Recent studies have revealed that the massive proliferation of synoviocytes and immune cells requires a large amount of energy supply. Rapid energy supply depends on the anaerobic glucose metabolic pathway in both RA animal models and clinical patients. Anaerobic glycolysis can increase intracellular lactic acid (LA) content. LA induces the overexpression of monocarboxylate transporters (MCTs) in cell membranes. MCTs rapidly transport LA from the intracellular to the intercellular or articular cavity. Hence, a relatively high accumulation of LA could be formed in the intercellular and articular cavities of inflammatory joints. Moreover, LA contributes to the migration and activation of immune cells. Immune cells proliferate and secrete interleukins (IL) including IL-1, IL-2, IL-13, IL-17, and other inflammatory factors. These inflammatory factors enhance the immune inflammatory response of the body and aggravate the condition of RA patients. In this paper, the effects of LA on RA pathogenesis will be summarized from the perspective of the production, transport, and metabolism of synoviocytes and immune cells. Additionally, the drugs involved in the production, transport, and metabolism of LA are highlighted.

Effects of paeoniflorin-6'-O-benzene sulfonate on the pharmacokinetics, excretion and tissue distribution of leflunomide in rats.

Paeoniflorin-6'-O-benzene sulfonate (CP-25) is a novel ester derivative of paeoniflorin, which has been shown to have synergistic pharmacodynamic effects with leflunomide (LEF). To determine the effects of CP-25 on the pharmacokinetics of LEF in rats, we developed a ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)-based method for the determination of levels of teriflunomide (TER, an active metabolite of LEF). This method was used to determine TER concentrations in the plasma, urine, faeces and bile; heart, liver, spleen, lung, kidney, intestinal, brain and synovial tissues; and peripheral blood mononuclear cells (PBMCs) of rats in the control (LEF [10 mg/kg]) and combined (CP-25 [50 mg/kg × 7d] plus LEF [10 mg/kg]) groups. TER area under the curve [AUC], Tmax , mean residence time (MRT), t1/2α and t1/2ß were significantly lower, and clearance (CL) was significantly higher in the combined group than in the control group. Oral CP-25 administration in combination with LEF was found to promote TER excretion in urine, faeces and bile and to reduce its contents in most tissues and organs, especially in the liver, which may reduce LEF-induced liver injury. CP-25 also increased TER exposure in the synovium and its absorption by PBMCs, and this could explain the synergistic effects of CP-25 and LEF.

The effects of drug transporters on the efficacy of methotrexate in the treatment of rheumatoid arthritis.

The ATP-binding cassette (ABC) and solute carrier (SLC) transporter families consist of common drug transporters that mediate the efflux and uptake of drugs, respectively, and play an important role in the absorption, distribution, metabolism and excretion of drugs in vivo. Rheumatoid arthritis (RA) is an autoimmune disease characterized by erosive arthritis, and there are many RA patients worldwide. Methotrexate (MTX), the first-choice treatment for RA, can reduce the level of inflammation, prevent joint erosion and functional damage, and greatly reduce pain in RA patients. However, many patients show resistance to MTX, greatly affecting the efficacy of MTX. Many factors, such as irrational drug use and heredity, are associated with drug resistance. Considering the effect of drug transporters on drugs, many studies have compared the expression of drug transporters in drug-resistant and drug-sensitive patients, and abnormal transporter expression and transport activity have been found in patients with MTX resistance. Thus, drug transporters are involved in drug resistance. This article reviews the effects of transporters on the efficacy of MTX in the treatment of RA.

Sedimentary chronology reinterpreted from Changshou Lake of the Three Gorges Reservoir Area reveals natural and anthropogenic controls on sediment production.

Sedimentary archives preserved in geomorphic sinks provide records of historical sediment dynamics and its related natural and anthropogenic controls. This study reinterpreted sedimentary processes in Changshou Lake of the Three Gorges Reservoir Area in China by combining a rainfall erosivity index with multiple tracing proxies, and the impacts of natural and anthropogenic drivers on sediment production were also explored. Erosive rainfalls with low frequency and large magnitude in the rainy season contribute to a substantial proportion of annual total rainfall, which thus can be used to infer erosion and sediment yield events. The sedimentary chronology was determined by comparing rainfall erosivity index with depth distribution of 137Cs and absolute particle size, which revealed annual sedimentation rates ranging from 1.1 to 2.3 cm a-1. The multi-proxy dating index and variation of sedimentation rate divided the sediment profile into three major periods. The reference period (1956-1982) displays low variability of TOC, TN, trace metal concentrations, and mean sedimentation rate. In the stressed period (1982-1998), industrial and sewerage discharge led to input and deposition of TOC, TN, and trace metals (e.g., Cd, Co, Cu, Cr, and Ni). The highest annual sediment accumulation rate of 2.3 cm a-1 may be ascribed to the 1982 big flood event. In the present period (1998-2013), increased TOC, TN and decreased trace metals in the top layers of the sediment core indicated changes in lake ecology. Fish farming promoted algal growth and primary productivity which caused eutrophication until 2004-2005. The reduced mean sedimentation rate of 1.7 cm a-1 between 1998 and 2004, and thereafter, may be attributed to soil and water conservation and reforestation policies implemented in the Longxi catchment. Human activities such as deforestation, cultural and industrial revolution, and lake eutrophication associated with fish farming since 1989, therefore led to appreciable limnological variations. Overall, the dated sedimentary profile from Changshou Lake displays high consistency with archived historical events and reflects the impact of both natural and anthropogenic controls on sediment production.

Linking sedimentary total organic carbon to 210Pbex chronology from Changshou Lake in the Three Gorges Reservoir Region, China.

The influences of total organic carbon (TOC) and total nitrogen (TN) on Lead-210 (210Pb) dating have recently been of increasing concern in lacustrine research. Sediment core from Changshou Lake in the Longxi catchment was investigated for influence of TOC on 210Pb dating. Lead-210 excess (210Pbex), Cesium-137 (137Cs) activities, TOC, TN, and particle size were measured. We proposed a dating index based on 137Cs chronology and particle size distribution of the lake sediment profile and rainfall erosivities calculated from Longxi catchment metrological records. Increasing trends in TOC and TN were specifically caused by commercial cage fish farming after 1989. The statistically significant correlation between 210Pbex activity, TOC (0.61, p = 0.04) and TN (0.51, p = 0.04), respectively explained post-1989 210Pb scavenging. The 210Pbex activity was closely related with coupled peaks of TOC and TN from mass depth 5-10 g cm-2. Higher TOC/TN ratio (8.33) indicated submerged macrophytes and native aquatic algal growth as main source of carbon from enhanced primary productivity because of massive fertilizer use and coherent climate warming. The study supported key hypothesis on vital role of fertilizer usage and algal derived TOC in controlling sedimentary 210Pbex activity at Changshou Lake sediment. 137Cs profile and erosive events as time markers provided reliable and consistent sedimentation rate of (1.6 cm y-1). 210Pbex activity decayed exponentially after peak at mass depth 5.68 g cm-2. Therefore, violation of 210Pb dating primary assumptions made it inappropriate for sediment dating at Changshou Lake. TOC content must be considered while using 210Pb as dating tool for lake sediment profiles.

Highly sensitive and selective dopamine biosensor based on 3,4,9,10-perylene tetracarboxylic acid functionalized graphene sheets/multi-wall carbon nanotubes/ionic liquid composite film modified electrode.

A sensitive and selective electrochemical sensor for determination of dopamine (DA) was fabricated based on 3,4,9,10-perylene tetracarboxylic acid functionalized graphene sheets, multi-wall carbon nanotubes and ionic liquid modified glass carbon electrode and the properties of modified electrode were characterized by scanning electron microscopy, transmission electron microscope and electrochemical impedance spectroscopy. The modified electrode showed excellent electrocatalytic activity toward the oxidation of DA. Meanwhile, a possible reaction mechanism related to the oxidation of DA was proposed. The differential pulse voltammetry was used for the determination of DA in the presence of 500 µM ascorbic acid and 330 µM uric acid under the optimum conditions and a good linear relationship between peak current and the concentration of DA was obtained in the concentration range from 0.03 µM to 3.82 mM with a detection limit of 1.2×10(-9) M (S/N=3). Moreover, the proposed method was successfully applied to determine DA in real sample and satisfactory results were obtained. The results showed that the modified electrode exhibits an excellent catalytic activity, good sensitivity, reproducibility and long-term stability.

A novel and simple strategy for simultaneous determination of dopamine, uric acid and ascorbic acid based on the stacked graphene platelet nanofibers/ionic liquids/chitosan modified electrode.

A promising electrochemical sensor for simultaneous determination of dopamine (DA), uric acid (UA) and ascorbic acid (AA) was fabricated based on the stacked graphene platelet nanofibers (SGNF)/ionic liquid (IL)/chitosan (CS) modified electrode. The SGNF/IL/CS modified electrode possessed excellent electrocatalytic activity towards the oxidation of DA, UA and AA with obvious reduction of over-potential and increased peak current, and the separations of oxidation peak potentials of DA-UA, DA-AA, and UA-AA were of 151, 213 and 364 mV, respectively. Under the optimum conditions, the linear range for the detection of DA, UA and AA were 0.05-240, 0.12-260, and 30-350 µM with the lowest detection limits of 0.05, 0.10 and 14.8 µM for DA, UA and AA, respectively. In addition, the electrochemical sensor showed high sensitivity, excellent selectivity, reproducibility and long-term stability.

A simple and 'green' synthesis of polymer-based silver colloids and their antibacterial properties.

Stable silver colloids were prepared using polyethylene glycol (PEG) as an environment friendly reduction agent and stabilizer, and with H2O as solvent. The Ag colloids were characterized by UV/VIS spectroscopy, transmission electron microscopy (TEM), and atom force microscopy (AFM). TEM and AFM of the sample showed uniform and monodispersive particle distribution in the colloids. The particle size is found to be less than 10 nm. The antibacterial activity of the Ag colloids was also studied. The results showed that the sample had high antibacterial activity toward Gram-positive and Gram-negative bacteria, and fungi.

Kinetic determination of tryptophan by using the B-Z oscillating chemical system.

A simple and rapid method was devised for determination of tryptophan, based on the Belousov-Zhabotinskii (B-Z) oscillating chemical system. Changes in oscillating period and amplitude were linearly proportional to the negative logarithm of L-tryptophan concentration over the range of 6.44 x 10(-7)-2.55 x 10(-4) M, with the regression coefficients of near unity and a lower detection limit of 6.5 x 10(-8) M. D-tryptophan was also examined although it is rarely found in most biological fluids, and perhaps not at all in natural proteins. The change of period against to negative logarithm of D-tryptophan concentration over the range of 4.9 x 10(-5)-8.24 x 10(-4) M is linear. Because the optimum conditions for determination of L- and D-tryptophan are not the same, a little amount of D-tryptophan does not affect the determination of L-tryptophan. Various influences were studied and a possible mechanism of perturbation to the B-Z oscillator by tryptophan was also discussed. Spectrophotometry and fluorescence spectrophotofluorimetry were used for comparison and confirmation of the results.

[Preparation of TiO2 pillared montmorillonite photocatalyst and its photocatalytic activity to degradation reaction of acidic fuchsine by sunlight].

TiO2 pillared montmorillonite composite photocatalyst was synthesized by acid-catalyzed sol method and characterized by IR, UV-Vis, TG/DTA, XRD, SEM etc. Spectral analyses have demonstrated that TiO2 pillared montmorillonite(Ti-MMT) has wider interlayer distance than Na substituted montmorillonite (Na-MMT) and higher optical absorption efficiency than nanoscale anatase TiO2. The photocatalytic degradation reaction of acidic fuchsine by sunlight was employed to evaluate the catalytic activity of the composite catalyst. It was found that, besides easy reclaimation, the photocatalytic activity of the catalyst was much higher than that of the pure nanosized anatase TiO2. When the addition amount of Ti-MMT is 0.2 g x (100 mL)(-1) and pH of acidic fuchsine solution is 3, the dye could be degraded thoroughly in 40 min and the degradation reaction obeys Langmuir- Hinshelwood equation.

[Preparation and catalytic activity for degradation of acidic fuchsine of TiO2 photocatalyst].

In the paper, undoped and Pr2O3 doped TiO2 nanoparticles were prepared by a sol-gel process using Ti(OC4H9)4 as raw material and characterized by means of XRD TG-DTA, AFM, UV-Vis and FTIR. The photocatalytic activity of Pr2O3/TiO2 was evaluated by the photocatalytic degradation of acidic fuchsine. The factors affecting on photocatalytic activity of Pr2O3/TiO2, such as the content of doped Pr2O3, the calcined temperature and added amount of the catalyst etc. were discussed. It was shown that Pr doping hampers the transformation of TiO2 crystal phase from anatase to rutile, and with Pr2O3 doping the particle diameter of Pr2O3/TiO2 samples decreased, the specific surface area increased and the photocatalytic activity improved. When doping amount of Pr is 0.8%, added amount of the catalyst is 0.03 g and the calcination temperature is 500 degrees C, the degradation efficiency of acidic fuchsine reaches 97%. The photocatalytic degradation of acidic fuchsine by Pr2O3/TiO2 is a quasi-first order dynamic reaction.

Determination of 1-naphthylamine by using oscillating chemical reaction.

A simple and rapid analytical method for determining 1-naphthylamine was proposed by perturbation with different amounts of 1-naphthylamine on the classical Belousov-Zhabotinskii (B-Z) oscillating chemical system. The results show that the changes both in oscillating period and amplitude were linearly proportional to the logarithm of the concentration of 1-naphthylamine (logC) very well ranging from 7.08x10(-5) to 7.08x10(-6) molL(-1) and 7.08x10(-5) to 1.0x10(-6) molL(-1), with the corresponding regression coefficient are 0.9957 and 0.9922, respectively. For the later, a lower detection limit of 5.64x10(-9) molL(-1) was obtained. Influence of injection point, temperature and reactant variables on this oscillating system was also investigated in detailed. The results obtained were compared with other determination methods. A possible reaction mechanism was interpreted by using bromide ion selective electrode to inspect the concentration change of Br(-) ion in the oscillating process.

Decoloration of aqueous Brilliant Green by using glow discharge electrolysis.

This paper described a plasma degradation of Brilliant Green (BG) by glow discharge electrolysis. Various influencing factors such as the voltage, the distance between cathode and anode were examined. Ultraviolet (UV) absorption spectra, gas chromatogram-mass spectrum (GC-MS), and chemical oxygen demand (COD) were used to monitor the degradation process and to identify the major oxidation intermediates. It was confirmed that benzoic acid, 1,2,3,4,5,6-cyclohexanehexaol, and carboxylic acids (e.g., oxalic acid, succinic acid and hydroxyacetic acid) were produced in the degradation process. The results showed that BG rapidly underwent degradation and eventually mineralized into CO(2) and H(2)O.

Degradation of 2,4-dichlorophenol by using glow discharge electrolysis.

Degradation of 2,4-dichlorophenol (2,4-DCP) in aqueous by glow discharge electrolysis (GDE) has been investigated. Ultraviolet (UV) absorption spectra, atomic force microscopy (AFM), high performance liquid chromatography (HPLC) and gas chromatogram-mass spectrum (GC/MS) are used to monitor the degradation process and to identify the major oxidation intermediate products. It has been found that 2,4-DCP undergoes a series of intermediate step, which leads to form a number of intermediate products, mainly isomeric chlorophenols and aliphatic acids. These products are further oxidized, eventually, mineralized into CO(2) and Cl(-). A degradation pathway for 2,4-DCP is proposed on the basis of detection of intermediate compounds.

Determination of furfural in an oscillating chemical reaction using an analyte pulse perturbation technique.

A rapid and convenient method for the determination of furfural is presented that is based upon sequential perturbation of the Mn(II)-catalyzed B-Z oscillating system with different amounts of furfural using a continuous-flow stirred tank reactor (CSTR). When the sample was injected, the change in the amplitude and/or period was linearly proportional to the logarithm of the concentration of furfural over the range 3 x 10(-8) approximately 1 x 10(-5) mol L(-1). This method gave a detection limit of 3 x 10(-9) mol L(-1) under optimum conditions. Finally, the possible mechanism of furfural perturbation in the oscillating reaction is discussed. When the furfural was injected into the Mn(II)-catalyzed B-Z oscillating system, the change in the amplitude and/or period was linearly proportional to the logarithm of the concentration of furfural over the range 3 x 10(-8)~1 x 10(-5) mol L(-1), with a detection limit of 3 x 10(-9) mol L(-1) under optimum conditions.

Improved sensitivity for some [corrected] metal ions by use of sulfide in the Belousov-Zhabotinskii oscillating reaction.

A highly sensitive method for the determination of trace amounts of some [corrected] metal ions by use of sulfide in the Belousov-Zhabotinskii (B-Z) oscillating chemical reaction is proposed. The use of sulfide increased strongly the sensitivity of the B-Z reaction for some [corrected] metal ions, such as Ag+, Pb2+, Hg2+, Cd2+, Cu2+, and Bi3+. Results showed that the variational ratio of oscillating period (P(R)) is linearly proportional to the negative logarithm of concentration of metal ions. The detection limit is down to 10(-12) mol L(-1). Various influencing factors on the determination were also examined.