Preparation and Characterization of a Porous Scaffold Based on Poly(D,L-Lactide) and N-Hydroxyapatite by Phase Separation

In this study, a series of porous scaffolds were prepared from poly(D,L-lactide) (PLA) and nanohydroxyapatite (HA) using the phase separation method. HA/PLA composite membranes and PLA membranes with a microporous structure (pore size around 10–20 μm) were observed by scanning electron microscopy and these micropores were well distributed throughout the PLA membranes. The surface morphology of HA/PLA composite membranes was significantly improved compared to pure PLA membrane. Also, the mechanical property and contact angle of composite membranes were different from that of pure PLA films. The immortalized rat osteoblastic ROS 17/2.8 cell line was used in this research to study the cell adhesion and proliferation behavior, and the results indicated that composite membranes had great cell affinity and good biocompatibility.     

Molecularly imprinted bioartificial membranes for the selective recognition of biological molecules. Part 2: release of components and thermal analysis

Molecularly imprinted membranes imprinted for a large-molecular-weight protein were realised using a blend of natural and synthetic polymers. Bioartificial membranes of synthetic (poly(ethylene-co-vinyl alcohol)–EVAL, Clarene^®) and biological (Dextran) polymers, molecularly imprinted with α-amylase as the template, were prepared and investigated. Dimethyl sulfoxide (DMSO) solutions of the α-amylase template, Clarene and Dextran were mixed under stirring in the desired proportions and dipped in DMSO (solvent)/water (non solvent) mixture, to obtain the phase separation. The release of Clarene, Dextran and α-amylase in the inversion baths was quantified by spectrophotometric methods and final composition of membranes was established. To study the interactions between the polymer components and between polymeric materials and the template, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were carried out. Results indicated that stable and continuous bioartificial membranes of Clarene and Dextran can be obtained, whereby calorimetric analysis suggested the presence of high interaction between α-amylase and the Clarene component.     

Monocytes and γδ T cells control the acute‐phase response to intravenous zoledronate: Insights from a phase IV safety trial

Aminobisphosphonates (NBPs) are used widely against excessive bone resorption in osteoporosis and Paget's disease as well as in metastatic bone disease and multiple myeloma. Intravenous NBP administration often causes mild to severe acute‐phase responses (APRs) that may require intervention with analgesics and antipyretics and lead to treatment noncompliance and nonadherence. We here undertook a phase IV safety trial in patients with osteoporosis to investigate the APR of otherwise healthy individuals to first‐time intravenous treatment with the NBP zoledronate. This study provides unique insight into sterile acute inflammatory responses in vivo, in the absence of confounding factors such as infection or cancer. Our data show that both peripheral γδ T cells and monocytes become rapidly activated after treatment with zoledronate, which ultimately determines the clinical severity of the APR. Our study highlights a key role for IFN‐γ in the zoledronate‐induced APR and identifies pretreatment levels of monocytes and central/memory Vγ9/Vδ2 T cells as well as their responsiveness to zoledronate in vitro as predictive risk factors for the occurrence of subclinical and clinical symptoms. These findings have diagnostic and prognostic implications for patients with and without malignancy and are relevant for Vγ9/Vδ2 T‐cell–based immunotherapy approaches. © 2012 American Society for Bone and Mineral Research. © 2013 American Society for Bone and Mineral Research.     

Focusing on β-amyloid: Report of the 35th Annual Meeting of the Society for Neuroscience

Newly described human serum amyloid A4 (SAA₄) was measured in serum by an enzyme-linked immunosorbent assay using anti-SAA4 monoclonal antibody and recombinant human SAA₄ as the assay standard. Interference by elevated acute phase SAA (aSAA) was abolished by the addition of rabbit anti-human aSAA antiserum prior to the addition ofanti-SAA₄ to the test samples. Normal levels of SAA₄ ranged between 80–140 mg/L, substantially higher than those ofaSAA. No statistically significant difference in SAA₄ levels between normal subjects and patients with Mycoplasma pneumonia was seen, indicating that SAA4 does not behave as an acute phase reactant. Low SAA₄ levels were found in some patients with high aSAA, although no significant relationship between SAA₄ and aSAA was apparent. The constitutive presence of SAA₄ in serum suggests a physiologic function different from that ofaSAA.     

人参提取液、药渣压滤液、药渣中人参皂苷含量对比研究

【目的】对比观察人参提取液、药渣压滤液、药渣中人参皂苷Rg1、Rb1和Re的含量。【方法】采用高效液相色谱(HPLC)法检测5批次人参提取液(按2005版中国药典所述方法进行提取)、药渣压滤液和药渣中人参皂苷Rg1、Rb1和Re的含量。【结果】人参药渣压滤液中人参皂苷Rg1、Rb1和Re含量与人参提取液比较差异均无统计学意义(P>0.05),但药渣中人参皂苷含量较人参提取液和人参药渣压滤液均显著减少(P<0.01),人参药渣中残留有较多的人参皂苷等有效成分,占提取的20%以上。【结论】药渣压滤液和药渣中均含有较高的人参皂苷Rg1、Rb1和Re等有效组分,药渣压滤液应与提取液混合入药,人参提取后药渣应加以开发利用。     

Novel bifunctional polymer with reactivity and temperature sensitivity

To introduce reactive groups into temperature-responsive polymeric chains of poly(N-isopropylacrylamide) (PIPAAm), IPAAm is copolymerized with other monomer such as acrylic acid (AAc). IPAAm homopolymer exhibited temperature-responsive properties and phase transition at 32°C, however, the lower critical solution temperature (LCST) of the IPAAm-AAc copolymer shifts to a higher temperature and the phase transition becomes insensitive with increasing AAc content. To achieve a useful bifunctional copolymer containing both reactivity and temperature-sensitivity, we assumed that the homopolymer-like structure in the polymer chain would be required to maintain a sensitive temperature response with functional groups. Therefore, we designed a reactive monomer, 2-carboxyisopropylacrylamide (CIPAAm), and investigated its copolymerization with IPAAm. The important characteristic of the poly(IPAAm-co-CIPAAm) structure is that it was composed of the same polymer backbone and isopropylamide groups and some additional carboxyl groups. The transmittance measurement of the polymer aqueous solution revealed that phase transition of IPAAm-co-CIPAAm random copolymer occurred within a very narrow temperature range in pH 6.4, 7.4, and also even 9.0 phosphate buffered solution. These profiles were almost same as that of IPAAm homopolymer. While, under the same conditions, phase transition properties of poly(IPAAm-co-AAc)s solution were considerably influenced by small AAc content. We succeeded with the preparation of bifunctional polymer that possessed reactive functional groups and very sensitive response to temperature change.     

Leptin as an acute phase reactant after non-adjustable laparoscopic gastric banding

Background: Leptin is a hormone that regulates food intake; its concentrations are elevated in the majority of obese individuals. During inflammation, plasma leptin is usually increased and may contribute to the anorexia and cachexia of infection.The purpose of this study was to characterize the dynamics of circulating leptin in the early postoperative period in relation to the acute phase response in extremely obese patients undergoing laparoscopic non-adjustable gastric banding (LNAGB). We compared plasma leptin changes with 4 proinflammatory cytokines and BMI. Methods:The prospective study was performed on 18 patients with 3rd degree obesity. Plasma concentration of leptin, tumor necrosis factor-α (TNF-α), interleukin (IL)-1, soluble IL-2 receptor (sIL-2R), and IL-6 were estimated before operation and 24, 48, and 72 h after NALGB. Results: We demonstrate statistically significant elevation of plasma leptin concentration (32.2±10.2 μg/l) 24 h after operation compared with preoperative status (18.4±5.2 μg/l, p<0.05). There was diminished correlation of plasma leptin and BMI in this period. Leptin levels +48 and +72 h after banding quickly returned to preoperative levels. The regression coefficient was the highest for leptin and TNFalpha 24 h after surgery (r = 0.40, p < 0.05), and for leptin and IL-6 24 h after surgery (r = 0.29, p < 0.05). There was no significant correlation between leptin and IL-1 and between leptin and sIL-2R respectively. Conclusions: During the non-infectious stress response (as with abdominal surgery), leptin shows itself as an acute phase reactant. Proinflammatory cytokines can be the main regulatory factors of leptin in this period.Significant correlation between leptin and TNF-alpha (similarly demonstrated by other authors in models of bacterial inflammation) indicates that TNF-alpha can be a crucial regulator of leptin generation in the early postoperative period.