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Homopolymers of acrylamide and acrylic acid are known to be hydrophilic and soluble in water. Their copolymers are soluble in water at neutral pH but can be turned into polymers possessing an upper critical solution temperature (UCST) behavior when the carboxylic acid groups are protonated (pH < 3). At temperatures below the UCST, the formation of interchain hydrogen bonds between the acid and amide groups makes the copolymers insoluble. These hydrogen bonds are disrupted when the temperature is heated above the critical temperature (Tc), exhibiting a UCST behavior. In this study, linear water-soluble random copolymers of acrylamide and acrylic acid of different compositions and molar masses have been synthesized. The thermoresponsive properties of the copolymers were studied to elucidate the effects of their composition, molar mass, and concentration by measuring their cloud point temperatures (Tcp) in acidic buffer solutions to keep the carboxylic acid groups in the protonated state. The effects of pH and added salts or urea were also studied.

The aim of this study was to identify the effects of melatonin on acute gouty inflammation and to investigate the underlying mechanisms. We found significantly lower serum melatonin levels in gout patients in the acute phase than in those in the remission phase or in normal individuals. The mRNA expression of melatonin receptor 2 (MT2) was also lower in gout patients than in normal individuals. To verify the in-vivorole of melatonin, a gouty arthritis model was established by intraarticular injection of monosodium urate (MSU, 1 mg) crystals into the paws of C57BL/6 mice. Joint inflammation in the mouse model was evaluated by measuring the thickness of the right paw/left paw, and the inflammation index was determined by examining infiltrating neutrophils with haematoxylin and eosin (H&E) staining. Melatonin was found to reduce both paw thickness and the inflammation index in the mouse model, and melatonin also reduced the mRNA levels of interleukin-1 beta (IL-1β), IL-6 and NLR family pyrin domain containing 3 (NLRP3) inflammasome. To mimic gouty inflammation in vitro, mouse peritoneal macrophages were stimulated with lipopolysaccharides (LPS) plus MSU. Melatonin was revealed to reduce IL-1β secretion by stimulated macrophages. The mRNA expression levels of IL-1β and IL-6 were also inhibited by melatonin. Western blot analysis showed that the expression of NLRP3, caspase-1 and pro-IL-1β was also inhibited by melatonin. In conclusion, our study demonstrated that melatonin alleviated gouty inflammation in vivoand in vitro, and the underlying mechanism may involve inhibiting the assembly of the NLRP3 inflammasome.

Silent information regulator T1 (SIRT1) plays several key roles in the regulation of lipid and glucose homoeostasis. In this study, we investigated the potential role of SIRT1 in hyperuricemia and explored possible mechanisms. Significant hyperuricemia was detected in C57BL/6 mice treated with oxonate and yeast polysaccharide. Resveratrol (RSV), a specific SIRT1 activator, was administered to the mice. SIRT1 suppressed the increased serum uric acid level but up-regulated the expression of urate transporter ATP-binding cassette subfamily G member 2 (ABCG2) in the ileum of hyperuricemic mice. In a human colon carcinoma cell line, SIRT1 promoted ABCG2 production through the deacetylation of peroxisome proliferator-activated receptor (PPAR) γ co-activator 1α (PGC-1α), which then activated the effectors of PPARγ. Interestingly, the SIRT1-induced up-regulation of ABCG2 was significantly inhibited when PGC-1α or PPARγ was blocked by siRNA transfection. Our data demonstrated that SIRT1 and its activator, RSV, have clear anti-hyperuricemia functions in this mouse model. One possible mechanism is the activation of ABCG2 in the ileum through the PGC-1α/PPARγ pathway.

Aim:SCT800 is a new third-generation recombinant FVIII agent that is undergoing promising preclinical study. This study aimed to investigate the pharmacokinetic and pharmacodynamic profiles of SCT800 in hemophilia A mice.Methods:After hemophilia A mice were intravenously injected with single dose of SCT800 (80, 180, and 280 IU/kg) or the commercially available product Xyntha (280 IU/kg), pharmacokinetics profiles were evaluated based on measuring plasma FVIII: C. For pharmacodynamics study, dose-response curves of SCT800 and Xyntha (1–200 IU/kg) were constructed using a tail bleeding model monitoring both bleeding time and blood loss.Results:Pharmacokinetics profile analysis showed a dose independency of SCT800 ranging from 80 to 280 IU/kg and comparable pharmacokinetic profiles between SCT800 and Xyntha at the doses tested. Pharmacodynamics study revealed comparable ED50values of SCT800 and Xyntha in the tail bleeding model: 14.78 and 15.81 IU/kg for bleeding time, respectively; 13.50 and 13.58 IU/kg for blood loss, respectively. Moreover, at the doses tested, the accompanying dose-related safety evaluation in the tail bleeding model showed lower hypercoagulable tendency and wider dosage range potential for SCT800 than Xyntha.Conclusion:In hemophilia A mice, SCT800 shows comparable pharmacokinetics and pharmacodynamics to Xyntha at the doses tested, and possibly with better safety properties.

The advanced manufacturing technology (AMT) is the important symbol of the national industrial modernization level. Because of fuzzy and uncertainty of reference information for decision,traditional evaluation methods often determined not accurately and efficiently. According to the evaluation of problem, based on the Fuzzy control technology, this paper firstly put forward a method of fuzzy group multi-criteria decision-making, which applies with the information of either weight coefficient or policymakers weight coefficient incompletely and decision makers having risk attitudes. Then on the basis of constructing the evaluation criterion system of advanced manufacturing technology, an example of some enterprise with AMT selecting project evaluation is given to explain the feasibility and availability of this method for helping decision-makers in determining the optimal conditions of AMT in uncertain environment.

We have found that a soft, hydrophilic shell is necessary in the formation of three‐dimensional colloidal crystals by polymeric microspheres prepared by surfactant‐free emulsion copolymerization. The core‐shell microspheres contain a hard, hydrophobic polystyrene core and a soft, hydrophilic shell made of polyacrylamide or poly(acrylic acid) (PAA). Dilution of the particles induced a red shift of the diffraction peak. We have found a pH switching effect for the formation of colloidal crystals by the microspheres with a PAA shell. When the carboxylic‐acid groups are protonated, the colloidal crystals lose their order. The same effect is observed when a poor solvent is added to the colloidal crystals formed by the microspheres with a polyacrylamide shell.

This article presents a new and promising way to design a temperature sensor, which is based on the micellization or aggregation behavior of binary diblock copolymers of poly(ethylene glycol)‐b‐poly(N‐isopropylacrylamide) (PEG‐b‐PNIPAM) and poly(ethylene glycol)‐b‐poly(4‐vinylpyridine) (PEG‐b‐P(4‐VP)). The temperature sensor presents both a lower critical response temperature (LCRT) and an upper critical response temperature (UCRT), where the thermoreversible aggregating of PEG‐b‐P(4‐VP) and H2SO4 is used to control the LCRT, and the thermoreversible micellization of PEG‐b‐PNIPAM is used to control the UCRT. Furthermore, the LCRT can be altered by changing the H2SO4 concentration, and the UCRT can be adjusted by altering the PEG‐b‐PNIPAM concentration. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3144–3148, 2006

Summary:Suspension polymerization yielded microspheres (40–50 μm) of polyacrolein. Smooth and rugged surfaces can be created by varying the polymerization procedure. We have shown that the polyacrolein resins with a high loading of aldehyde groups serve as effective scavengers for primary amines and may be used to remove compounds bearing amino groups in the combinatorial synthesis of compound libraries. Copolymerization with styrene can help to separate the adjacent aldehyde groups, thus making the functional groups more available in organic reactions. The polyacrolein resins in the aldehyde form or after appropriate chemical modifications may also be useful as support materials in solid‐phase synthesis.

Thermosensitive copolymers of poly(N-isopropyl acrylamide)-co-2-hydroxyethyl methacrylate (NIPA-co-HEMA) macroporous resins were synthesized in the form of beads by inverse suspension polymerization. The copolymerization was carried out in aqueous solutions of the comonomers dispersed by cyclohexane with stabilizers. A series of resins with different molar ratios of NIPA : HEMA, and different crosslinking degrees was obtained. The compositions of the copolymers were determined by elemental analysis. The results showed that the content of HEMA in a copolymer was higher than that of the corresponding feed mixture from which the copolymer was made. IR spectra also confirmed the structure of the copolymers. The porous parameters such as true densities, apparent densities, pore volumes, and porosities of the resins were measured by means of pycnometry. The determination of equilibrium swelling ratios and measurement of differential scanning calibration indicated that the resins exhibited thermosensitivity in aqueous solutions. Finally, the loading of hydroxyl groups was determined by titration. The resins have potential applications as supports in solid-phase synthesis after being functionalized. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1792–1797, 2004

Linear copolymers from N-isopropylacrylamide (NIPA), acrylic acid (AA) and diacetone acrylamide (DAA) have been prepared. The effect of composition, ionic strength and pH on their lower critical solution temperature (LCST) has been investigated.

A novel multiplex analysis technology based on quantum dot (QD) optical encoded beads was studied. Carboxyl functionalized polystyrene beads, about 100 μm in size, were precisely encoded by the various ratios of two types of QDs whose emission wavelengths are 576 and 628 nm, respectively. Then the different encoded beads were covalently immobilized with different probes in the existing of sulfo-NHS and 1-[3-(Dimethylamino) propyl]-3-ethylcarbodiimide methiodide, and the probe density could reach to 3.1 mmol/g. These probe-linked encoded beads were used to detect the target DNA sequences in complex DNA solution by hybridization. Hybridization was visualized using fluorescein isothiocynate–labeled DNA sequences. The results show that the QDs and target signals can be obviously identified from a single-bead-level spectrum. This technology can detect DNA targets effectively with a detection limit of 0.2 μg/mL in complex solution.

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