A Novel Approach to Synthesize Helix Wave Hollow Fiber Membranes for Separation Applications

Helix wave hollow fiber membranes are promising candidate to mitigate fouling and polarization effects in membrane operations. Current study describes a novel but simple approach to synthesize hollow fiber membranes with helix wave configuration. Poly(ether sulfone) (PES) based helix-waved hollow fiber membranes have been fabricated by dry-wet phase inversion process by using asymmetric coagulation conditions. Frequencies of the wave cycle have been observed approximately 20 and the wave length 7.1-7.6mm under the specifically required operating conditions defined by dope solution extrudate rate of 1g/min through 4cm of air-gap heights with 8.6m/min of winding speeds. On the other hand, simple hollow fibers are formed when the elongation force exerted by the winder is much higher than the surface tension of the external coagulant. The process can be useful for making polymer fibers for other applications as well

CO₂ Fixation by Membrane Separated NaCl Electrolysis

Atmospheric concentrations of carbon dioxide (CO2), a major cause of global warming, have been rising due to industrial development. Carbon capture and storage (CCS), which is regarded as the most effective way to reduce such atmospheric CO2 concentrations, has several environmental and technical disadvantages. Carbon capture and utilization (CCU), which has been introduced to cover such disadvantages, makes it possible to capture CO2, recycling byproducts as resources. However, CCU also requires large amounts of energy in order to induce reactions. Among existing CCU technologies, the process for converting CO2 into CaCO3 requires high temperature and high pressure as reaction conditions. This study proposes a method to fixate CaCO3 stably by using relatively less energy than existing methods. After forming NaOH absorbent solution through electrolysis of NaCl in seawater, CaCO3 was precipitated at room temperature and pressure. Following the experiment, the resulting product CaCO3 was analyzed with Fourier transform infrared spectroscopy (FT-IR); field emission scanning electron microscopy (FE-SEM) image and X-ray diffraction (XRD) patterns were also analyzed. The results showed that the CaCO3 crystal product was high-purity calcite. The study shows a successful method for fixating CO2 by reducing carbon dioxide released into the atmosphere while forming high-purity CaCO3

GarlicESTdb: an online database and mining tool for garlic EST sequences

<p>Abstract</p> <p>Background</p> <p><it>Allium sativum</it>., commonly known as garlic, is a species in the onion genus (<it>Allium</it>), which is a large and diverse one containing over 1,250 species. Its close relatives include chives, onion, leek and shallot. Garlic has been used throughout recorded history for culinary, medicinal use and health benefits. Currently, the interest in garlic is highly increasing due to nutritional and pharmaceutical value including high blood pressure and cholesterol, atherosclerosis and cancer. For all that, there are no comprehensive databases available for Expressed Sequence Tags(EST) of garlic for gene discovery and future efforts of genome annotation. That is why we developed a new garlic database and applications to enable comprehensive analysis of garlic gene expression.</p> <p>Description</p> <p>GarlicESTdb is an integrated database and mining tool for large-scale garlic (<it>Allium sativum</it>) EST sequencing. A total of 21,595 ESTs collected from an in-house cDNA library were used to construct the database. The analysis pipeline is an automated system written in JAVA and consists of the following components: automatic preprocessing of EST reads, assembly of raw sequences, annotation of the assembled sequences, storage of the analyzed information into MySQL databases, and graphic display of all processed data. A web application was implemented with the latest J2EE (Java 2 Platform Enterprise Edition) software technology (JSP/EJB/JavaServlet) for browsing and querying the database, for creation of dynamic web pages on the client side, and for mapping annotated enzymes to KEGG pathways, the AJAX framework was also used partially. The online resources, such as putative annotation, single nucleotide polymorphisms (SNP) and tandem repeat data sets, can be searched by text, explored on the website, searched using BLAST, and downloaded. To archive more significant BLAST results, a curation system was introduced with which biologists can easily edit best-hit annotation information for others to view. The GarlicESTdb web application is freely available at <url>http://garlicdb.kribb.re.kr</url>.</p> <p>Conclusion</p> <p>GarlicESTdb is the first incorporated online information database of EST sequences isolated from garlic that can be freely accessed and downloaded. It has many useful features for interactive mining of EST contigs and datasets from each library, including curation of annotated information, expression profiling, information retrieval, and summary of statistics of functional annotation. Consequently, the development of GarlicESTdb will provide a crucial contribution to biologists for data-mining and more efficient experimental studies.</p

Cardioprotective Effect of the SDF-1α/CXCR4 Axis in Ischemic Postconditioning in Isolated Rat Hearts

Background and Objectives: Information about the role of the stromal cell-derived factor1a (SDF-1 alpha)/chemokine receptor type 4 (CXCR4) axis in ischemic postconditioning (IPOC) is currently limited. We hypothesized that the SDF-1 alpha/CXCR4 signaling pathway is directly involved in the cardioprotective effect of IPOC. Methods: Isolated rat hearts were divided into four groups. The control group was subjected to 30-min of regional ischemia and 2-hour of reperfusion (n=12). The IPOC group was induced with 6 cycles of 10-second reperfusion and 10-second global ischemia (n=8) in each cycle. The CXCR4 antagonist, AMD3100, was applied before reperfusion in the IPOC group (AMD+IPOC group, n=11) and control group (AMD group, n=9). Hemodynamic changes with electrocardiography were monitored and infarct size was measured. The SDF-1 alpha, lactate dehydrogenase (LDH) and creatine kinase (CK) concentrations in perfusate were measured. We also analyzed extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt phosphorylation state expression. Results: IPOC significantly reduced infarct size, but AMD3100 attenuated the infarct reducing effect of IPOC. IPOC significantly decreased LDH and CK, but these effects were reversed by AMD3100. ERK1/2 and Akt phosphorylation increased with IPOC and these effects were blocked by AMD3100. Conclusion: Based on the results of this study, SDF-1 alpha/CXCR4 signaling may be involved in IPOC cardioprotection and this signaling pathway couples to the ERK1/2 and Akt pathways.111Ysciescopuskc

Cardioprotective Effect of the SDF-1α/CXCR4 Axis in Ischemic Postconditioning in Isolated Rat Hearts

Information about the role of the stromal cell-derived factor-1α (SDF-1α)/chemokine receptor type 4 (CXCR4) axis in ischemic postconditioning (IPOC) is currently limited. We hypothesized that the SDF-1α/CXCR4 signaling pathway is directly involved in the cardioprotective effect of IPOC

Evaluation of 28 Human Embryonic Stem Cell Lines for Use as Unrelated Donors in Stem Cell Therapy: Implications of HLA and ABO Genotypes

For human embryonic stem cells (hESCs) to be used clinically, it is imperative that immune responses evoked by hESCs and their derivates after transplantation should be prevented. Human leukocyte antigens (HLA) and ABO blood group antigens are important histocompatibility factors in graft rejection. HLA matching between recipient and unrelated donors, in particular, is important in improving outcomes in hematopoietic cell transplantation (HCT). We have established and successfully maintained 29 hESC lines and analyzed the HLA and ABO genotypes of these lines. HLA-A, -B, -C and -DR (DRB1) genotyping was performed by polymerase chain reaction (PCR) sequence-based typing and ABO genotyping was carried out by PCR restriction fragment length polymorphism methods. To determine what proportion of the Korean population would be covered by these cell lines in organ transplantation, 27 cell lines with HLA-A, -B, and -DR data were evaluated for HCT (cord blood) donors and 28 cell lines with HLA-DR and ABO data were evaluated for solid organ (kidney) transplantation donors, and then compared the data with those from 6,740 donated cord bloods. When <= 2 HLA mismatches are allowed for HCT, as currently accepted for cord blood transplantation, it was estimated that about 16% and 25% of the possible recipients can find one or more donor cell lines with mismatches at A, B, DRB1 allele level and at A, B antigen/DRB1 allele level, respectively. When HLA-DR antigen level matching and ABO compatibility was considered for solid organ (kidney) transplantation, it was estimated that about 29% and 96% of the possible recipients can find one or more ABO-compatible donor cell lines with 0 and 1 DR mismatches, respectively. We provided the first report on the HLA and ABO genotypes of hESC lines, and estimated the degree of HLA and ABO matching in organ transplantation for the Korean population.Yu JY, 2009, SCIENCE, V324, P797, DOI 10.1126/science.1172482Kaji K, 2009, NATURE, V458, P771, DOI 10.1038/nature07864Lee JY, 2010, FERTIL STERIL, V93, P976, DOI 10.1016/j.fertnstert.2008.10.017Holdsworth R, 2009, TISSUE ANTIGENS, V73, P95, DOI 10.1111/j.1399-0039.2008.01183.xLehec SC, 2009, CELL TRANSPLANT, V18, P941, DOI 10.3727/096368909X471323Oishi K, 2009, CELL TRANSPLANT, V18, P581Molne J, 2008, TRANSPLANTATION, V86, P1407, DOI 10.1097/TP.0b013e31818a6805Fernandes AM, 2010, CELL TRANSPLANT, V19, P509, DOI 10.3727/096368909X485067Stadtfeld M, 2008, SCIENCE, V322, P945, DOI 10.1126/science.1162494Wang GW, 2005, BIOCHEM BIOPH RES CO, V330, P934, DOI 10.1016/j.bbrc.2005.03.058Hoffman LM, 2005, NAT BIOTECHNOL, V23, P699, DOI 10.1038/nbt1102Li Y, 2005, BIOTECHNOL BIOENG, V91, P688, DOI 10.1002/bit.20536Vallier L, 2005, J CELL SCI, V118, P4495, DOI 10.1242/jcs.02553Taylor CJ, 2005, LANCET, V366, P2019Boyd AS, 2005, ADV DRUG DELIVER REV, V57, P1944, DOI 10.1016/j.addr.2005.08.004Ludwig TE, 2006, NAT BIOTECHNOL, V24, P185, DOI 10.1038/nbt1177Drukker M, 2006, STEM CELLS, V24, P221, DOI 10.1634/stemcells.2005-0188Priddle H, 2006, STEM CELLS, V24, P815, DOI 10.1634/stemcells.2005-0356Reubinoff BE, 2000, NAT BIOTECHNOL, V18, P399Amit M, 2000, DEV BIOL, V227, P271Xu CH, 2001, NAT BIOTECHNOL, V19, P971Drukker M, 2002, P NATL ACAD SCI USA, V99, P9864, DOI 10.1073/pnas.142298299Richards M, 2002, NAT BIOTECHNOL, V20, P933, DOI 10.1038/nbt726Bradley JA, 2002, NAT REV IMMUNOL, V2, P859, DOI 10.1038/nri934Amit M, 2003, BIOL REPROD, V68, P2150, DOI 10.1095/biolreprod.102.012583Li L, 2004, STEM CELLS, V22, P448Drukker M, 2004, TRENDS BIOTECHNOL, V22, P136, DOI 10.1016/j.tibtech.2004.01.003Thomson JA, 1998, SCIENCE, V282, P1145Petersdorf EW, 1999, CURR OPIN IMMUNOL, V11, P521Bodnar MS, 2004, STEM CELLS DEV, V13, P243Koivisto H, 2004, REPROD BIOMED ONLINE, V9, P330Rocha V, 2004, NEW ENGL J MED, V351, P2276Laughlin MJ, 2004, NEW ENGL J MED, V351, P2265Lee JB, 2005, BIOL REPROD, V72, P42, DOI 10.1095/biolrepod.104.033480Xu RH, 2005, NAT METHODS, V2, P185, DOI 10.1038/NMETH744Beattie GM, 2005, STEM CELLS, V23, P489, DOI 10.1634/stemcells.2004-0279Genbacev O, 2005, FERTIL STERIL, V83, P1517, DOI 10.1016/j.fertnstert.2005.01.086Oh SKW, 2006, CLIN EXP PHARMACOL P, V33, P489Skottman H, 2006, FEBS LETT, V580, P2875, DOI 10.1016/j.febslet.2006.03.083Xiao L, 2006, STEM CELLS, V24, P1476, DOI 10.1634/stemcells.2005-0299Stussi G, 2006, TRANSFUS APHER SCI, V35, P59, DOI 10.1016/j.transci.2006.05.009Takahashi K, 2006, CELL, V126, P663Guhr A, 2006, STEM CELLS, V24, P2187, DOI 10.1634/stemcells.2006-0053Klumpp TR, 2006, BONE MARROW TRANSPL, V38, P615, DOI 10.1038/sj.bmt.1705496Nakajima F, 2007, STEM CELLS, V25, P983, DOI 10.1634/stemcells.2006-0566Huangfu DW, 2008, NAT BIOTECHNOL, V26, P1269, DOI 10.1038/nbt.1502Petersdorf EW, 2008, CURR OPIN IMMUNOL, V20, P588, DOI 10.1016/j.coi.2008.06.014Chen YT, 2008, STEM CELLS DEV, V17, P853, DOI 10.1089/scd.2007.0226Park IH, 2008, CELL, V134, P877, DOI 10.1016/j.cell.2008.07.041Swijnenburg RJ, 2008, P NATL ACAD SCI USA, V105, P12991, DOI 10.1073/pnas.0805802105Unger C, 2008, HUM MOL GENET, V17, pR48, DOI 10.1093/hmg/ddn079Drukker M, 2008, SEMIN IMMUNOL, V20, P123, DOI 10.1016/j.smim.2007.11.002Revazova ES, 2008, CLONING STEM CELLS, V10, P11, DOI 10.1089/clo.2007.0063Mountford JC, 2008, TRANSFUSION MED, V18, P1, DOI 10.1111/j.1365-3148.2007.00807.xPark IH, 2008, NATURE, V451, P141, DOI 10.1038/nature06534Nakagawa M, 2008, NAT BIOTECHNOL, V26, P101, DOI 10.1038/nbt1374Buzzeo MP, 2008, CELL TRANSPLANT, V17, P489Kamani N, 2008, BIOL BLOOD MARROW TR, V14, P1, DOI 10.1016/j.bbmt.2007.11.003Saric T, 2008, CELLS TISSUES ORGANS, V188, P78, DOI 10.1159/000118784Navarro-Alvarez N, 2008, CELL TRANSPLANT, V17, P27KASTENBERG ZJ, 2008, TRANSPLANT REV ORLAN, V22, P215Lee SJ, 2007, BLOOD, V110, P4576, DOI 10.1182/blood-2007-06-097386Shaw BE, 2007, BLOOD, V110, P4560, DOI 10.1182/blood-2007-06-095265Strom S, 2007, HUM REPROD, V22, P3051, DOI 10.1093/humep/dem35Lin G, 2007, CELL RES, V17, P999, DOI 10.1038/cr.2007.97Crook JM, 2007, CELL STEM CELL, V1, P490Helming AM, 2007, PEDIATR BLOOD CANCER, V49, P313, DOI 10.1002/pbc.21025Cabrera CM, 2007, CELL BIOL INT, V31, P1072, DOI 10.1016/j.cellbi.2007.03.015Lei T, 2007, CELL RES, V17, P682, DOI 10.1038/cr.2007.61Okita K, 2007, NATURE, V448, P313, DOI 10.1038/nature05934Wernig M, 2007, NATURE, V448, P318, DOI 10.1038/nature05944Maherali N, 2007, CELL STEM CELL, V1, P55, DOI 10.1016/j.stem.2007.05.014Eapen M, 2007, LANCET, V369, P1947

Oxygen-deficient triple perovskites as highly active and durable bifunctional electrocatalysts for oxygen electrode reactions

Highly active and durable bifunctional oxygen electrocatalysts have been of pivotal importance for renewable energy conversion and storage devices, such as unitized regenerative fuel cells and metal-air batteries. Perovskite-based oxygen electrocatalysts have emerged as promising nonprecious metal bifunctional electrocatalysts, yet their catalytic activity and stability still remain to be improved. We report a high-performance oxygen electrocatalyst based on a triple perovskite, Nd1.5Ba1.5CoFeMnO9-delta (NBCFM), which shows superior activity and durability for oxygen electrode reactions to single and double perovskites. When hybridized with nitrogen-doped reduced graphene oxide (N-rGO), the resulting NBCFM/N-rGO catalyst shows further boosted bifunctional oxygen electrode activity (0.698 V), which surpasses that of Pt/C (0.801 V) and Ir/C (0.769 V) catalysts and which, among the perovskite-based electrocatalysts, is the best activity reported to date. The superior catalytic performances of NBCFM could be correlated to its oxygen defect rich structure, lower charge transfer resistance, and smaller hybridization strength between O 2p and Co 3d orbitals