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Objective: This study aimed to improve the utilization value of scallop processing by-products, by analyzing the antioxidant activity of its protein hydrolysates. Methods: The processing by-products of Argopecten irradians were used as raw materials, and the proteins were extracted by alkali extraction and acid precipitation, alkali extraction and ammonium sulfate precipitation and low temperature ethanol denaturation precipitation. Then the proteins were analyzed by SDS-PAGE. Pepsin, flavourzyme, dispase and alcalase were used to hydrolyze the protein, and the antioxidant activities of the hydrolysate products were analyzed. The molecular weight distribution, amino acid composition and hydroxyproline content of dispase hydrolysates were further analyzed. Results: The purity of protein obtained by alkaline ammonium sulfate precipitation method was the highest, reaching 91.16%, with the optima electrophoretic results. All the four hydrolysates had DPPH, ABTS, hydroxyl radical scavenging ability and reducing ability, and the dispase hydrolysate showed the highest antioxidant ability, especially hydroxyl radical scavenging rate, which reached （77.24±1.87）%. The hydrolysate of dispase contained 15 kinds of amino acids such as aspartic acid, with a total content of 84 g/100 g, and the content of hydroxyproline reached （11.82±0.09）%. Conclusion: The protein obtained from the by-products of scallop processing by alkaline extraction and ammonium sulfate precipitation, and its dispase hydrolysates have optimal antioxidant activity and high nutritional value, which can be further developed as antioxidant functional food.

Carbon capture, utilization and storage (CCUS) technology is an effective way to mitigate the greenhouse effect. Using solid adsorbents to capture CO2 is considered to be one of reliable ways of reducing CO2 emissions. MgO-based adsorbents have attracted much attention due to their wide source, low regeneration temperature and high theoretical adsorption capacity in various solid adsorbents. However, the formed MgO-based adsorbents still face the problems of low mechanical strength, poor stability and easy to escape from the reactor, so they are difficult to be widely used in industry. The effects of different granulation methods and granulation process conditions on the CO2 adsorption performance of MgO-based adsorbents were summarized. In the granulation process, the MgO-based adsorbents with smaller particle sizes have faster carbonation rates and lower wear rates. The chemical properties and mechanical strength of adsorbent particles can be improved by adding proper amount of granulation additives and steam. However, higher calcination temperatures can exacerbate sintering and wear of absorbent particles. In the future, the research should focus on developing simplified processes, low costs and good cycle stability, and prepare absorbent particles with both excellent CO2 adsorption performance and mechanical properties for industrial-scale CO2 capture. [ABSTRACT FROM AUTHOR]

To improve the adsorption capacity of wheat biochar (BC) for arsenic (As), wheat stalks were selected as biomass to generate nano-sized goethite modified biochar (Goethite@BC) by co-precipitation. The adsorption capacities of BC, Goethite, and Goethite@BC for As(Ⅲ) were compared. The samples were analyzed by scanning electron microscopy (SEM) along with energy dispersive spectrometry (EDS), Brunauer-Emmett-Teller (BET), Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) techniques. The results showed that the nano-goethite coating was uniformly attached to the surface of the BC and improved the surface area and total pore volume of the biochar. The adsorption of As(Ⅲ) by the three adsorbents was proved to fit well with the pseudo-second-order kinetic model and the Langmuir model. Compared to BC, the Goethite@BC increased the adsorption rate of As(Ⅲ) by 62.10 times, and the maximum adsorption capacity of Goethite@BC was 65.20 mg·g -1 . The adsorption mechanism of Goethite@BC included non-specific adsorption (electrostatic attraction) and specific adsorption (coordination, complexation, ion exchange, etc.), and nano-goethite particles on the Goethite@BC surface played an important role in the adsorption of As. Goethite@BC has a good application prospects in the field of environmental remediation.

Objective: To establish a novel method to isolate endothelial progenitor cells（EPC） from cryopreserved umbilical cord blood (cryoUCB), to investigate the biological characteristics of EPC and to improve the rate of EPC obtained from cryoUCB., Methods: Twelve cryoUCB samples during 2000 to 2001 years were collected from allogeneic cord blood bank, cryoUCB was thawed rapidly in a water bath at 37 ℃, total nucleated cells (TNCs) were washed by phosphate-buffered saline (PBS). TNCs were seeded onto fibronectin-coated dishes to isolate EPC. Flow cytometry and immunofluorescence were used to identify EPC. The function of EPC was identified in vitro, such as the incorporation of Dil-Ac-LDL and FITC-UEA-I, the formation of capillary-like structure in matrigel, and the release of VEGF by ELISA., Results: One to five cluster of cobble stone-like cells appeared at 2-3 weeks after seeding. Flow cytometric analysis showed that positive rates of CD31, CD34, CD144, and VEGFR (CD309) were（92.91±5.20）%, （30.0±23.27）%, （88.55±3.83）% and （67.21±12.12）% in passage 1 to passage 3 of EPC. EPC could uptake Dil-Ac-LDL and FITC-UEA-I, form capillary-like network on Matriget and release VEGF., Conclusion: EPC had been successfully isolated from cryopreserved umbilical cord blood by this method with high stability and reproducibility. EPC can be obtained in 85% frozen umbilical cord blood. This method may lay a foundation to supply abundant EPC for clinical application.

Toad venom (Chansu) is prepared from the dried secretion of Bufo bufo gargarizans or B. melanostictus. It is not only one of the famous and expensive traditional Chinese medicines(TCMs) from animal origin, but also one of 28 kinds of toxic TCMs to be required for special management issued by the State Council of the People's Republic of China. Chansu contains the rich bufadienolides and indole alkaloids, and displays various bioactivity including cardiotonic, anti-tumor, analgesia, and local anesthesia. Based on the published references in the recent years, the advance on the identification of adulterants and quality evaluation as well as the influence factors on the quality of toad venom was summarized to improve the quality standards and promote the level of quality control of toad venom and its preparations., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

The study established the 1H NMR-based fingerprinting and analyzed 8 batches of Huangqi injection solution.1H NMR-based fingerprinting of both primary and secondary metabolites of Huangqi injection were established, and the 1H-1H chemical shift correlation spectroscopy (COSY) and 1H-13C chemical shift correlation spectroscopy (HSQC) were used to identify the chemical components in Huangqi injection solution. Coupled with similarity analysis and relative content determination,8 batches of Huangqi injection solution were analyzed. Twenty-five metabolites (both primary and secondary) were identified, and the significant differences were found in the chemical composition among these Huangqi samples. The content and content variation of the primary metabolites were much higher than those of the secondary metabolites, which was the major cause of the uniformity of the Huangqi injections. The results on the quality variations of Huangqi injections in this study will serve as a basis for improving the quality control.

Objective: To study the roles of the increased intracellular calcium induced rapidly by estrogen in the implantation of mouse blastocysts., Methods: The mouse blastocysts were collected from the female mice on the pregnant day 4, divided into 3 groups: control, E2-BSA and BAPTA +E2-BSA. Immunofluorescence staining, confocal microscopy, embryo and endometrial epithenial cells co-culture and embryo transfer were used to investigate the effect of increased intracellular calcium induced by E2-BSA on the expression and localization of integrins in blastocysts and their adhesion to endometrial epithenial calls (EECs) and implantation into the endometrium., Results: The increase of intracellular calcium induced rapidly by estrogen could cause the cluster and relocation of integrin av and beta3, and BAPTA might block this effect, the adhesion rate of blastocysts in contol group was 35.5%, BAPTA +E2-BSA group was 26.7% and significantly lower than 65.6% of E2-BSA group (P<0.05), and the implantation rate in BAPTA+E2-BSA group was 11.8%, which was significantly lower than 52.9% of E2-BSA group (P<0.05)., Conclusion: The rapid increase of intracellular calcium induced by estrogen may cause the relocalization of integrin in blastocysts and their adhesion to ECCs, which is important in the process of implantation.

Objective: To kinds of establish a HPLC method for determining contents of indole alkaloids and bufadienolides contained in toad medicines, and analyze two kinds of components contained in toad venom, toad skin and toad periostracum., Method: As for alkaloids, Nucleosil C18 column was adopted with acetonitrile and water containing 0.5% potassium dihydrogen phosphate (6: 94, adjust pH to 3.2 with phosphate acid) as the mobile phase. The flow rate was 0.8 mL x min(-1), the detection wavelength was 275 nm, and the column temperature was 30 degrees C. As for bufadienolides, Alltima C18 column was adopted with acetonitrile and water containing 0.3% acetic acid (B) as the mobile phase. The gradient process was as follows: a linear gradient from 28% to 54% acetonitrile in the first 15 min, then kept at 54% for additional 20 min. The flow rate was 0.6 mL x min(-1), the detection wavelength was 296 nm, and the column temperature was 30 degrees C., Result: The linear ranges were 0.079 6-0.796 microg for serotonin, 0.097 2-1.945 microg for N-methylserotonin, 0.074 4-0.744 microg for N,N-dimethylserotonin, 0.103-2.05 microg for N,N,N-trimethylserotonin, and 0.067 2-0.672 microg for bufothionine, respectively. The average recoveries of serotonin and N-methylserotonin were 98.6% and 91.3%, respectively. The linear ranges of gamabufotalin, bufotalin, bufalin, cinobufagin and resibufogenin were 0.004 83-0.614, 0.007 9-1.006, 0.007 95-1.016, 0.009 7-1.24 and 0.009 6-1.22 microg, respectively, and their average recoveries were 101.6%, 102.5%, 101.0%, 99.1% and 98.9%, respectively., Conclusion: Toad venom has the highest contents of indole alkaloids and bufadienolides, followed by toad skin, and toad periostracum showed the lowest contents and even no detection result.

Objective: To evaluate the inhibitory effect of total bufadienolides from toad venom against H22 tumor in mice and preliminarily analyze the structures of the metabolites in tissues., Method: HPLC and LC-MS were used for analysis of the chemical composition of TBFs. High, middle and low dosages of TBFs were orally administered or intra-peritoneally injected to H22 tumor-bearing mice for thirteen days. The animals were killed and the tumors were stripped and weighed. The metabolites in the tissues such as heart, liver, spleen, lung and kidney, were analyzed by HPLC and LC-MS., Result: The chemical composition of TBFs were identified by comparison of the retention times with those of reference substances, on-line UV spectra and MS data. Its main components are concerned with gamabufotalin, arenobufagin, bufotalin, resibufagin, cinobufotalin, bufalin, cinobufagin and resibufogenin. TBFs had no obvious influence on body weight of H-22 tumor-bearing mice orally administered and the inhibition rate against tumor were 14.76%, 16.38% and 10.32% for low (5 mg x kg(-1)), middle (10 mg x kg(-1)) and high dosage (20 mg x kg(-1)), respectively. The mice intra-peritoneally injected with middle and high-dose of TBFs gained body weight slower than the control mice on the 5th day and recovered on the 13th day. The inhibition rate against tumor were 17.30%, 19.80% and 40.95% for low (1.5 mg x kg(-1)), middle (3 mg x kg(-1)) and high dose (6 mg x kg(-1)), respectively. The inhibitory effect took on dose-dependent manner. Based on the HPLC analyses on heart, liver, spleen, lung and kidney, bufadienolides were found in the liver tissue and 11 compounds of them were tentatively identified by LC-DAD-MS., Conclusion: TBFs by oral administration had no inhibitory effect against H22 tumor in mice, however, TBFs by intra-peritoneal injection displayed the significantly inhibitory effect, accompanying some toxicity for early duration of the study. The identification of bufadienolides in the liver provides a good basis for the further investigation of the metabolic pathways of TBFs in vivo.

Objective: To identify the aminoglycoside resistance gene in the high-level gentamicin resistant (HLGR) enterococcus and its transmission mechanism., Methods: A HLGR strain, HZ95, of Enterococcus casseliflavus was screened by agar dilution method. The aminoglycoside activation enzyme genes were screened by PCR. The PCR products underwent purification, cloned, and sequenced. Plasmids were extracted and underwent Southern hybridization. Plasmid-mediated aminoglycoside modifying enzymes were cloned. The resistance of the HZ05 strain to different antimicrobial agents was determined by K-B method or agar dilution method., Results: A new aminoglycosides-modifying enzyme, APH (2'')-Ie, leading to HLGR, was found in the plasmid of the HZ95 bacteria. The aph (2'')-Ie gene and partial sequence of a streptomycin adenylyltransferase gene (str) were contained in the 8.7-kb cloned fragment, and the transposase gene (tnpA) was on the upper stream. The aph (2'')-Ie gene was located on the 16-kb plasmid with the amino acid sequence 96.1% homologous with chromosome-mediated APH (2'')-Id aminoglycoside-modifying enzyme., Conclusion: HLGR can be caused by a new plasmid-mediated aminoglycosides-modifying enzyme, APH (2'')-Ie, which can be transmitted among plasmids or chromosome with other resistant genes through transposase.

Objective: To determine the antibiotics resistance, aminoglycoside-modifying enzymes and homology of high-level gentamycin resistant enterococcus in clinical specimens., Methods: The high-level gentamicin resistant (HLGR) isolates were screened by the agar method and the resistance of 14 antimicrobial agents was determined by K-B method. The aminoglycoside-modifying enzyme genes were detected by polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE) was used to analyze the homology of HLGR isolates., Results: The ratio of HLGR was 64.2% (68/106). Among the HLGR,there were no isolates resistant to linezolid, vancomycin and tecoplanin, and Enterococcus faecium was more resistant to beta-lactam antibiotics and quinolone than Enterococcus faecalis. The positive rate of aac(6')-Ie-aph(2')-Ia was 92.6% and 3 isolates had the resistance gene mostly similar to aph(2')-Id. And among 51 HLGR isolates from the hospitalized patients, PFGE grouped 17 E. faecalis isolates into 4 clusters (A-D), and 33 E. faecium isolates into 8 clusters (A-H) with A cluster as predominant., Conclusion: HLGR has become the important antibiotic resistance bacteria which results in nosocomial infection; and aac(6')-Ie-aph(2')-Ia is the main aminoglycoside-modifying enzyme gene which causes HLGR.