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Inner Surface (inner + surface)
Selected AbstractsFS09.2 Contact allergy to a commercial alcohol prep swabCONTACT DERMATITIS, Issue 3 2004James S Taylor Allergic contact dermatitis to prepackaged disposable alcohol prep swabs is infrequently reported. A 60-year-old woman developed repeated episodes of dermatitis at sites of injections and venipunctures. History and patch testing revealed contact allergy to Kendall Webcol alchol prep swabs. There were negative patch test results to isopropyl alcohol (IPA), but positive reactions to the Webcol swab, to the inner surface of the packaging foil, to two other brands of alcohol swabs, and to bacitracin. UV absorbance profile analysis revealed the presence of UV absorbing materials at peaks of 221 and 280 nm within commercial IPA samples, including one from Kendall, which were absent from reagent grade IPA. Reports of similar cases identified IPA, propylene oxide, or both as the allergens; when swab ingredients were negative, compound allergy was proposed. A recent report from Korea identified dodecyldiaminoethylglycine and IPA as the allergens in the commercial disinfectant swab. Although the exact allergen is undetermined in our case, it may represent a chemical compound or contaminant that is used or acquired during the manufacturing of the swabs or foils. [source] Further studies on knockout mice lacking a functional dynein heavy chain (MDHC7).CYTOSKELETON, Issue 2 2005Abstract Male mice had been previously generated in which the inner dynein arm heavy chain 7 gene (MDHC7) was disrupted. MDHC7,/, animals show asthenozoospermia and are sterile. Very few of their spermatozoa can achieve forward progression, but for those that can, we add here the information (1) that the three-dimensional aspects of their movement are normal; (2) that their maximum velocity is less than that of wild-type controls; and (3) that they are entirely unable to penetrate media of raised viscosity (25,4,000 cP). However, the large majority of the spermatozoa can achieve only a low amplitude vibration. In these sperm we find, using electron microscopy, that the outer dense fibres retain attachments to the inner surface of the mitochondria. Such attachments are present in normal epididymal mouse spermatozoa but are broken down as soon as the sperm become motile on release from the epididymis. The attachments are presumed to be essential during midpiece development and, afterwards, to require a threshold level of force to loosen them and so permit the sliding displacements necessary for normal bending. We presume that the disruption of the inner dynein arm heavy chain gene, MDHC7, means that there is insufficient force to overcome the attachments, for all but a few spermatozoa. Cell Motil. Cytoskeleton 61:74,82, 2005. © 2005 Wiley-Liss, Inc. [source] Epidermoid cyst of the intrapancreatic accessory spleen producing CA19-9DIGESTIVE ENDOSCOPY, Issue 3 2004Hiroyuki Watanabe We report a rare case of an epidermoid cyst in an accessory spleen at the pancreatic tail with producing CA19-9. A 55-year-old female was admitted to our hospital, Cancer Research Institute, Kanazawa University, for close examination of a cystic lesion at the pancreatic tail and a high serum CA19-9-value (176 U/mL). There were almost no abdominal symptoms related to the cystic lesion. A cystic tumor approximately 3 cm in diameter and composed of multilocular cysts without a protruding portion of the inner surface was found at the pancreatic tail by ultrasound sonography, computed tomography, and magnetic resonance imaging. Endoscopic retrograde pancreatography revealed that the main pancreatic duct shifted at the pancreatic tail and there was no communication between the main pancreatic duct and cystic lesion. Based on a preoperative diagnosis of mucinous cystic tumor, distal pancreatectomy with splenectomy was performed. Histological ,ndings suggested an epidermoid cyst (3.5 × 3.0 cm) originating from an intrapancreatic accessory spleen. Immunohistochemical analysis of CA19-9 in the epidermoid cyst showed clear staining of the inner epithelium of the cyst and amorphous or hyalinous cystic contents. The serum CA19-9 value was con,rmed to decline to normal 2 months after resection. Physicians should not forget this disease during differential diagnosis related to pancreatic cystic lesions with elevated levels of serum tumor markers, such as CA19-9 or carcinoembryonic antigen, although this disease is extremely rare. [source] CE coupled to MALDI with novel covalently coated capillariesELECTROPHORESIS, Issue 4 2010Stefan Bachmann Abstract CE offers the advantage of flexibility and method development options. It excels in the area of separation of ions, chiral, polar and biological compounds (especially proteins and peptides). Masking the active sites on the inner surface of a bare fused silica capillary wall is often necessary for CE separations of basic compounds, proteins and peptides. The use of capillary surface coating is one of the approaches to prevent the adsorption phenomena and improve the repeatability of migration times and peak areas of these analytes. In this study, new capillary coatings consisting of (i) derivatized polystyrene nanoparticles and (ii) derivatized fullerenes were investigated for the analysis of peptides and protein digest by CE. The coated capillaries showed excellent run-to-run and batch-to-batch reproducibility (RSD of migration time ,0.5% for run-to-run and ,9.5% for batch-to-batch experiments). Furthermore, the capillaries offer high stability from pH 2.0 to 10.0. The actual potential of the coated capillaries was tested by combining CE with MALDI-MS for analysing complex samples, such as peptides, whereas the overall performance of the CE-MALDI-MS system was investigated by analysing a five-protein digest mixture. Subsequently, the peak list (peptide mass fingerprint) generated from the mass spectra of each fraction was entered into the Swiss-Prot database in order to search for matching tryptic fragments using the MASCOT software. The sequence coverage of analysed proteins was between 36 and 68%. The established technology benefits from the synergism of high separation efficiency and the structure selective identification via MS. [source] Co-electroosmotic capillary electrophoresis of basic proteins with 1-alkyl-3-methylimidazolium tetrafluoroborate ionic liquids as non-covalent coating agents of the fused-silica capillary and additives of the electrolyte solutionELECTROPHORESIS, Issue 11 2009Danilo Corradini Abstract The paper reports the results of a study carried out to evaluate the use of three 1-alkyl-3-methylimidazolium-based ionic liquids as non-covalent coating agents for bare fused-silica capillaries and additives of the electrolyte solutions (BGE) for CE of basic proteins in the co-EOF separation mode. The three ionic liquids are differentiated from each other by the length of the alkyl group on the imidazolium cation, consisting of either an ethyl, butyl or octyl substituent, whereas tetrafluoroborate is the common anionic component of the ionic liquids. Coating the capillary with the ionic liquid resulted in improved peak shape and protein separation, while the EOF was maintained cathodic. This indicates that each ionic liquid is effective at masking the protein interaction sites on the inner surface of the capillary, also when its adsorption onto the capillary wall has not completely neutralized all the negative charges arising from the ionization of the silanol groups and the ionic liquid is not incorporated into the BGE employed for separation. Using the coated capillaries with BGE containing the ionic liquid employed for the coating, at concentration low enough to maintaining the EOF cathodic, both peak shape and protein separation varied to different extents, based on the particular ionic liquid used and its concentration. Fast and efficient separation of the model basic protein mixture in co-electroosmotic CE is obtained with the 1-butyl-3-methylimidazolium tetrafluoroborate coated capillary and 100,mM acetate buffer (pH 4.0) containing 4.4,mM 1-butyl-3-methylimidazolium tetrafluoroborate as the BGE. [source] Preparation and characterization of temperature-responsive capillary electrochromatographic column using poly(N -isopropylacrylamide)ELECTROPHORESIS, Issue 4 2009Rongji Dai Abstract Poly(N -isopropylacrylamide) is a temperature-responsive polymer, which is hydrophilic at low temperature but hydrophobic at high temperature. Using this characteristic, the polymer was bonded to the inner surface of fused-silica capillary to prepare a temperature-responsive column to study the separation behavior in electrochromatography. [source] Carboxylic multi-walled carbon nanotubes as immobilized stationary phase in capillary electrochromatography,ELECTROPHORESIS, Issue 18 2008Lorena Sombra Abstract Carboxylic multi-walled carbon nanotubes (c-MWNT) have been immobilized into a fused-silica capillary for capillary electrochromatography. The c-MWNT were successfully incorporated after the silanization and coupling with glutaraldehyde on the inner surface of the capillary. The electrochromatographic features of the c-MWNT immobilized stationary phase have been evaluated for the analysis of different compounds of pharmaceutical interest. The results indicated high electrochromatographic resolution, good capillary efficiency and retention factors. In addition, highly reproducible results between runs, days and capillaries were obtained. [source] Open-tubular capillary electrochromatography using a capillary coated with octadecylamine-capped gold nanoparticlesELECTROPHORESIS, Issue 4 2008Qishu Qu Dr. Abstract Octadecylamine-capped gold nanoparticles (ODA-Au-NPs) were prepared and characterized by using UV,Vis adsorption spectrum, transmission electron chromatography (TEM), SEM, and FT-IR. A simple but robust hydrophobic coating was easily developed by flushing a capillary with a solution of ODA-Au-NPs, because the positive charges were carried by the nanoparticles which strongly adsorb to the negatively charged inner surface of a fused-silica capillary via electrostatic and hydrophobic interactions. The chromatographic characteristics of the coated capillary was investigated by varying the experimental parameters such as buffer pH, buffer concentration, and percentage of organic modifier in the mobile phase. The results show that (i) resolution between thiourea and naphthalene is almost the same when comparing the electrochromatograms obtained using pH,7 buffer as mobile phase after and before the capillary column was operated using pH,11 and 3 mobile phase; (ii) no significant changes in retention time and deterioration in peak efficiency were found after 60,runs of test aromatic mixtures; and (iii) column efficiency up to 189,000 theoretical plates/meter for testosterone was obtained. All of the results indicated that the coating could act as a stable stationary phase for open tubular CEC as well as for bioanalysis. [source] Separation of cationic polymer particles and characterization of avidin-immobilized particles by capillary electrophoresisELECTROPHORESIS, Issue 5-6 2006Yukihiro Okamoto Abstract Cationic polymer microparticles have received much attention especially in the field of biotechnology, such that their analysis and separation have become important. So far, the separation of cationic polymer particles with different size using CE has not been achieved and the cationic particles migrated as if they are negatively charged, probably due to electrostatic interaction between capillary wall and cationic polymer particles. In this paper, the separation of cationic polymer microparticles by CE was investigated in detail. The separation of cationic particles with different size was achieved in CE by taking into account the interaction between sample particles and the inner surface of capillaries. By employing a poly(vinyl alcohol)-coated capillary, a better size separation of amine-modified latex particles was obtained compared to a Polybrene-coated capillary. It was elucidated that the composition, concentration, and pH of the background solution were also important factors in the separation of colloidal particles to avoid the surface adsorption and the characteristic aggregation of polymer particles. Furthermore, the CE analysis was applied to the characterization of cationic protein-immobilized particles. [source] Nanowires for surface enlargement of narrow-bore fused-silica tubingELECTROPHORESIS, Issue 21-22 2004Andreas Woldegiorgis Abstract A method for preparation of silica nanowires with dimensions of d = 10,100 nm, l = 5,500 nm, is described. The nanostructured material is an integral part of the inner surface of narrow bore fused-silica capillary tubing. The wire preparation method is based on a decomposition of 2-chloro-1,1,2-trifluoroethyl methyl ether at elevated temperature and pressure. The silica bulk material is rearranged via a sustained silica-hydrogen fluoride chemistry, and reaction mechanisms for this process are proposed. The method is suitable for preparing long lengths of tubing with the modified surface. It is our belief that the texture of the capillary wall with its increased surface area is useful for applications such as microreactions, catalysis, and high-resolution pressure and/or electrodriven open-tubular liquid chromatography. [source] Advances in sol-gel based columns for capillary electrochromatography: Sol-gel open-tubular columnsELECTROPHORESIS, Issue 22-23 2002Abdul Malik Abstract The development of sol-gel open-tubular column technology in capillary electrochromatography (CEC) is reviewed. Sol-gel column technology offers a versatile means of creating organic-inorganic hybrid stationary phases. Sol-gel column technology provides a general approach to column fabrication for microseparation techniques including CEC, and is amenable to both open-tubular and monolithic columns. Direct chemical bonding of the stationary phase to the capillary inner walls provides enhanced thermal and solvent stability to sol-gel columns. Sol-gel stationary phases inherently possess higher surface area, and thus provide an effective one-step alternative to conventional open-tubular column technology. Sol-gel column technology is applicable to both silica-based and transition metal oxide-based hybrid stationary phases, and thus, provides a great opportunity to utilize advanced material properties of a wide range of nontraditional stationary phases to achieve enhanced selectivity in analytical microseparations. A wide variety of stationary phase ligands can be chemically immobilized on the capillary inner surface using a single-step sol-gel procedure. Sol-gel chemistry can be applied to design stationary phases with desired chromatographic characteristics, including the possibility of creating columns with either a positive or a negative charge on the stationary phase surface. This provides a new tool to control electroosmotic flow (EOF) in the column. Column efficiencies on the order of half a million theoretical plates per meter have been reported for sol-gel open-tubular CEC columns. The selectivity of sol-gel stationary phases can be easily fine-tuned by adjusting the composition of the coating sol solution. Open-tubular columns have significant advantages over their packed counterparts because of the simplicity in column making and hassle-free fritless operation. Open-tubular CEC columns possess low sample capacity and low detection sensitivity. Full utilization of the analytical potential of sol-gel open-tubular columns will require a concomitant development in the area of high-sensitivity detection technology. [source] Hydrophobically Directed Aldol Reactions: Polystyrene-Supported L -Proline as a Recyclable Catalyst for Direct Asymmetric Aldol Reactions in the Presence of Water,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 28 2007Michelangelo Gruttadauria Abstract A simple synthetic methodology for the preparation of a polystyrene-supported L -proline material is reported, and this material has been used as catalyst in direct asymmetric aldol reactions between several ketones and arylaldehydes to furnish aldol products in high yields and stereoselectivities. Screening of solvents showed that these reactions take place only in the presence of water or methanol, at lower levels of conversion in the latter case. This solvent effect, coupled with the observed high stereoselectivities, has been explained in terms of the formation of a hydrophobic core in the inner surface of the resin, whereas the hydrophilic proline moiety lies at the resin/water interface. Such a microenvironment both promotes the aldol reaction and increases the stereoselectivity. Recycling investigations have shown that this material can be reused, without loss in levels of conversion and stereoselectivity, for at least five cycles. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Synchrotron-Based Micro-CT and Refraction-Enhanced Micro-CT for Non-Destructive Materials Characterisation,ADVANCED ENGINEERING MATERIALS, Issue 6 2009Bernd R. Müller Abstract X-ray computed tomography is an important tool for non-destructively evaluating the 3-D microstructure of modern materials. To resolve material structures in the micrometer range and below, high brilliance synchrotron radiation has to be used. The Federal Institute for Materials Research and Testing (BAM) has built up an imaging setup for micro-tomography and -radiography (BAMline) at the Berliner storage ring for synchrotron radiation (BESSY). In computed tomography, the contrast at interfaces within heterogeneous materials can be strongly amplified by effects related to X-ray refraction. Such effects are especially useful for materials of low absorption or mixed phases showing similar X-ray absorption properties that produce low contrast. The technique is based on ultra-small-angle scattering by microstructural elements causing phase-related effects, such as refraction and total reflection. The extraordinary contrast of inner surfaces is far beyond absorption effects. Crack orientation and fibre/matrix debonding in plastics, polymers, ceramics and metal-matrix-composites after cyclic loading and hydro-thermal aging can be visualized. In most cases, the investigated inner surface and interface structures correlate to mechanical properties. The technique is an alternative to other attempts on raising the spatial resolution of CT machines. [source] Closed-form thermal stress intensity factors for an internal circumferential crack in a thick-walled cylinderFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 8 2010R. GHAJAR ABSTRACT In this paper the method of weight functions is employed to calculate the stress intensity factors for an internal circumferential crack in a thick-walled cylinder. The pressurized cylinder is also subjected to convection cooling on the inner surface. Finite element method is used to determine an accurate weight function for the crack and a closed-form thermal stress intensity factor with the aid of the weight function method is extracted. The influence of crack parameter and the heat transfer coefficient on the stress intensity factors are determined. Comparison of the results in the special cases with those cited in the literature and the finite element data shows that the results are in very good agreement. [source] Nacre in Mollusk Shells as a Multilayered Structure with Strain GradientADVANCED FUNCTIONAL MATERIALS, Issue 7 2009Boaz Pokroy Abstract How do living organisms attain the complicated shapes of grown bio-composites? This question is answered when studying the mechanics of the nacre layer in the bivalve mollusk shells. In this study, the internal strains/stresses across the shell thickness are profiled as a function of depth by strain gauge measurements during controlled etching in the selected areas. Measurements of stress release under etching provide clear evidence that the investigated shells, in fact, are strained multilayered structures, which are elastically bent due to the forces evolving at the organic/inorganic interfaces. The stresses are mostly concentrated in the "fresh" nacre sub-layers near the inner surface of the shell adjacent to the mollusk mantle. This analysis unexpectedly shows that the elastic bending of the nacre layer is due to strain gradients which are originated in the gradual in-depth changes of the thickness of ceramic lamellae. The changes mentioned were directly observed by scanning electron microscopy. By this sophisticated design of the ultra-structure of the nacre layer, the bowed shape of the bivalve shells is apparently achieved. [source] Middle Meningeal Artery Dilatation in MigraineHEADACHE, Issue 10 2009Dip MFOS, Elliot Shevel BDS, MB BCh Objective., To show that migraine pain is not related to dilatation of the dural meningeal arteries. Background., The origin of the pain in migraine has not yet been adequately explained and remains the subject of vigorous debate. Current theories implicate changes in the trigeminovascular system, which is defined as comprising the large intracranial vessels, and in particular, the dural meningeal vessels, the dura mater, and their neural connections. Methods., The anatomical relationships of the dural meningeal arteries to the dura mater and the inner surface of the calvarium are described. Results., The dural meningeal arteries lie in grooves in the inner table of the calvarium, are encased in the unyielding fibrous dura mater, and are consequently unable to dilate. Conclusion., The pain of migraine is not related to dilatation of the dural meningeal arteries. [source] Hyaluronan synthase-3 is upregulated in metastatic colon carcinoma cells and manipulation of expression alters matrix retention and cellular growthINTERNATIONAL JOURNAL OF CANCER, Issue 5 2003Kelli M. Bullard Abstract HA is a glycosaminoglycan that is synthesized on the inner surface of the plasma membrane and secreted into the pericellular matrix. HA and its biosynthetic enzymes (HAS1, HAS2 and HAS3) are thought to participate in tumor growth and cancer progression. In our study, colon carcinoma cells isolated from a lymph node metastasis (SW620) produced more pericellular HA and expressed higher levels of HAS3 mRNA compared to cells isolated from a primary colon carcinoma (SW480). To assess functionality, HAS3 expression in SW620 cells was inhibited by transfection with an asHAS3 construct. Decreased HA secretion and cell-surface retention by asHAS3 transfectants were confirmed using competitive binding and particle exclusion assays. Anchorage-independent growth, a correlate of tumor growth in vivo, was assessed by colony formation in soft agar. SW620 cells stably transfected with asHAS3 demonstrated significant growth inhibition, as evidenced by fewer colonies and smaller colony area than either SW620 cells or cells transfected with vector alone. Addition of exogenous HA restored growth in asHAS3 transfectants. Thus, we demonstrate that pericellular HA secretion and retention and HAS3 expression are increased in metastatic colon carcinoma cells relative to cells derived from a primary tumor. Inhibition of HAS3 expression in these cells decreased the pericellular HA matrix and inhibited anchorage-independent growth. These data suggest that HA and HAS3 function in the growth and progression of colon carcinoma. © 2003 Wiley-Liss, Inc. [source] Rules-of-thumb of implementing short electric band heaters (length to diameter ratio <1.5) for external heating of pipe flowsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2002X. D. Chen Abstract Short electric band heaters (L/Di<1.5) are constructed for the ease of implementation in small scale heating applications. They are usually mounted side-by-side in series along the external wall of a pipe for heating the fluid within the pipe. There are no rules-of-thumb available about designing such a system to achieve good uniformity of the temperature profile at the pipe inner surface beforehand. Non-uniformity can cause preferential fouling at hotter spots. This study focuses on the axial uniformity of heating along a pipe inside which the heated fluid if flowing. The situation has been simplified a great deal in mathematical terms from the corresponding conventional conjugate problem considered previously due to the small temperature rise in the fluid flow through one section of the pipe which is heated by one band heater. Similarity parameter sets have been deduced and verified by numerical simulations. The worst scenario of non-uniformity for such short band heaters, that is when L/Di=1.5, is presented in this paper. This may be used for designing a system to minimize the non-uniformity in terms of choosing the right pipe material, percentage of heater wire coverage in the band heater, etc. Copyright © 2002 John Wiley & Sons, Ltd. [source] An interaction between opticin and heparan sulfate may provide the molecular basis for vitreoretinal adhesionINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2004V. John Hindson Introduction Opticin is a member of the extracellular matrix small leucine-rich repeat (SLRP) proteoglycan/protein family, which was originally identified in the eye associated with the collagen fibrils of the vitreous humour. A putative heparin/heparan sulfate (HS) binding motif (RKERKRR) was identified at the N-terminus of human opticin, but this is absent in the bovine form. Furthermore, the strength of attachment between the vitreous and the retina was observed to be species-dependent and related to the presence or absence of this motif. We hypothesized that opticin cross-links the collagen fibrils of the vitreous to HS proteoglycans in the inner limiting lamina (a basement membrane on the inner surface of the retina), contributing towards vitreoretinal adhesion. Materials and methods Recombinant human and bovine opticin were expressed in 293-EBNA cells and purified to apparent homogeneity. Solid phase assays and surface plasmon resonance studies were used to characterize interactions between immobilized heparin/HS and opticin. Results Solid phase and BIAcore data revealed that human opticin binds heparin/HS and binds to heparin with a dissociation constant of approximately 20 nm. By contrast bovine opticin, which lacks the basic cluster, bound severalfold less tightly. Competition studies with heparin oligosaccharides indicated that the heparin/HS binding site is greater than 6 monosaccharides in length. Heparin, HS, chondroitin sulfate A (CS-A), dermatan sulfate and hyaluronan all competed with heparin for binding to human opticin but CS-C did not. Discussion Work to date suggests that the N-terminal sequence RKERKRR contributes significantly to the binding of opticin to heparin/HS. Vitreoretinal adhesion plays a key role in a number of eye diseases and inhibitors of the opticin,HS interaction could be of therapeutic value. [source] Optimum design of electromagnetic shielding rooms with minimum usage of absorbing materialsINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 1 2010S. M. J. Razavi Abstract In this article, a novel method has been proposed to optimize the electromagnetic shielding rooms. This method is based on using minimum electromagnetic absorbing materials on the inner surface of the rooms. The positions of the absorbing materials are found optimally to produce a "best" performance for the shielding rooms. The ray-tracing method is used to predict the shielding effectiveness (SE) of the electromagnetic shielding rooms with apertures. The performance of the proposed method is verified by a comprehensive example. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE 2010. [source] Dorsal onlay augmentation urethroplasty with small intestinal submucosa: Modified Barbagli technique for strictures of the bulbar urethraINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2006IVO I DONKOV Aim: To present the results from one clinic's experience of using small intestinal submucosa (SIS) in augmentation urethroplasty for management of strictures of the bulbar urethra. Methods: Urethral surgery was performed in nine men with strictures 4,6 cm. All of the patients were evaluated by history, physical examination, retrograde urethrogram, and uroflowmetry. Four layers of SIS were soaked in saline or Ringer's solution for 15 minutes at 37°C, and the inner surface of the patch was gently fenestrated with a thin scalpel. The patch was spread-fixed onto the tunica albuginea. The mucosa was sutured to the submucosal graft first at 2,3 mm inwards from the SIS margins, then the spongiosum tissue was attached to the margins with interrupted absorbable sutures. Results: Of the nine patients who underwent augmentation urethroplasty using SIS, only one had re-stricture at 6 months due to urethral infection. At 18 months after the surgery the uroflowmetry of the other eight patients was 20,21 mL/s. In terms of complications, six patients reported having post-micturition dribbling, and seven patients reported lack of morning erections for 35,69 days after surgery. Conclusions: Using SIS is a safe procedure; however, long-term follow-up is needed to substantiate the good short-term results. [source] Synthesis of Rhodium Colloidal Nano-Coating Grafted Mesoporous Silica Composite and its Application as Efficient Environmentally Benign Catalyst for Heck-Type Reaction of Arylboronic AcidsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 5 2008Liang Li Abstract The synthesis and characterization of rhodium colloidal layer grafted mesoporous SBA-15 material, designated as SBA-Rh, are presented. In the preparation of this new catalyst, SBA-15 mesoporous material was used as support without any pretreatment. The SiH functional groups were introduced onto the surface which resulted in highly dispersed metal colloid layer both on the outer and inner surface of the supporting material. The material was investigated for Heck-type coupling reactions of alkenes with ayboronic in organic/water solvent. The ultrahigh specific area, large pore opening, and highly dispersed catalyst species in SBA-Rh material created one of the most active heterogeneous catalysts for such reactions. Rhodium element was not detected in the final mixture by ICP after reaction. The catalyst species showed very high stability against leaching from the matrix and can be recycled for repeated use. [source] Triphase Hydrogenation Reactions Utilizing Palladium-Immobilized Capillary Column Reactors and a Demonstration of Suitability for Large Scale SynthesisADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 15 2005Juta Kobayashi Abstract We have developed a practical and highly productive system for hydrogenation reactions utilizing capillary column reactors, which occupy less space than ordinary batch systems, are low cost and easy to handle, and show feasibility toward large-scale chemical synthesis. Palladium-containing micelles were immobilized onto the inner surface of the capillaries. Nine palladium-immobilized capillaries were assembled and connected to a T-shaped connector, and hydrogen and a substrate solution were fed to capillaries via the connector. Hydrogenation of 1-phenyl-1-cyclohexene (1) proceeded smoothly to give phenylcyclohexane in quantitative yield. The capillaries themselves occupy only ca. 0.4,mL and a high space-time yield has been achieved (124.3,mg/17,min/0.4,mL). In addition, leaching of palladium was not detected by ICP analysis after reactions. [source] Formation of the Fertilization Pore during Oogenesis of the Fern Ceratopteris thalictroidesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 6 2010Jian-Guo Cao The development of the fertilization pore during oogenesis of the fern Ceratopteris thalictroides was followed using transmission electron microscopy. The newly formed egg is appressed closely to the adjacent cells. There are well-developed plasmodesmata between the egg and the ventral canal cell, but none between the egg and the jacket cells of the archegonium. During maturation, a separation cavity is formed around the egg. However, a pore region persistently connects the egg and the ventral canal cell. The extra egg membrane is formed by deposition of sheets of endoplasmic reticulum (ER), but no ER is deposited on the inner surface of the pore region. Thus, a fertilization pore, covered by a layer of plasmalemma, is formed. The ventral canal cell undoubtedly participates the formation of the fertilization pore, probably by absorbing the sheets of ER beneath the pore region. The functional significance of the ventral canal cell in formation of the fertilization pore is discussed. The features of the mature egg include that abundant concentric membranes and osmiophilic vesicles occur in the cytoplasm of the mature egg. The initial, round nucleus of the egg eventually becomes cup-shaped. This investigation gives some new insights about the cells participating oogenesis in ferns. [source] Catheter-Based Transendocardial Myocardial Gene TransferJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2002CHRISTER SYLVÉNM.D. Ph.D. Background and Aim: Local modulation of myocardial function by gene transfer or cell depositions constitutes a potential method of cardiac treatment. This study tested the morphology of myocardial plasmid gene transfer by catheter-based transendocardial injection (NOGA). Methods: Left ventricular morphology and electrical and mechanical characteristics were mapped in three dimensions. In two pigs, 0.10 mL oftoluidine blue was injected at ten sites. In seven pigs, seven to ten injections of 0.10 mL saline containing 0.10 mg pCMV-LacZ expressing the enzyme ,-galactosidase and 0.10 mg phVEGF-A165 were given. The pigs were sacrificed after 3 days and gene expression was determined. Results: Macroscopically on the endocardial surface, all identified spots were located in the target area. However, along the transmyocardial axis, injections with color and plasmid were located randomly throughout the left ventricular wall from the endocardium to the epicardium. In each detected spot, gene expression of ,-galactosidase was observed in an approximate myocardial volume of 5 × 5 × 5 mm. Microscopically, the transfected cells were located typically at the tip of the injection scar. As a rule, 10 to 20 transfected cells were located at the end of the injection scar. In sections where expression of both transcripts was observed, 42% of the cells expressed both ,-galactosidase and vascular endothelial growth factors (VEGF), 32% only ,-galactosidase, and 26% only VEGF. Conclusions: Myocardial gene transfer following magnetic guidance can be located precisely on the left ventricular inner surface. Within the myocardium, gene expression is local around the distal tip of the injection scar and is located randomly at every level of depth of the left ventricular wall. [source] Automatic model-based evaluation of magnetic resonance-guided radio frequency ablation lesions with histological correlationJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2004Roee S. Lazebnik PhD Abstract Purpose To develop a model-based method for automatic evaluation of radio frequency (RF) ablation treatment using magnetic resonance (MR) images. Materials and Methods RF current lesions were generated in a rabbit thigh model using MR imaging (MRI) guidance. We created a 12-parameter, three-dimensional, globally deformable model with quadric surfaces that delineates lesion boundaries and is automatically fitted to MR grayscale data. We applied this method to in vivo T2 - and contrast-enhanced (CE) T1 -weighted MR images acquired immediately post-ablation and four days later. We then compared results to manually segmented MR and three-dimensional registered corresponding histological boundaries of cellular damage. Results Resulting lesions featured a two-boundary appearance with an inner region and an outer hyperintense margin on MR images. For automated vs. manual MR boundaries, the mean errors over all specimens were 0.19 ± 0.51 mm and 0.27 ± 0.52 mm for the inner surface, and ,0.29 ± 0.40 mm and ,0.12 ± 0.17 mm for the outer surface, for T2 - and CE T1 -weighted images, respectively. For automated vs. histological boundaries, mean errors over all specimens were 0.07 ± 0.64 mm and 0.33 ± 0.71 mm for the inner surface, and ,0.27 ± 0.69 mm and 0.02 ± 0.43 mm for the outer surface, for T2 - and CE T1 -weighted images, respectively. All boundary errors compared favorably to MR voxel dimensions, which were 0.7 mm in-plane and 3.0 mm thick. Conclusion The method is accurate both in describing MR-apparent boundaries and in predicting histological response and has applications in lesion visualization, volume estimation, and treatment evaluation. J. Magn. Reson. Imaging 2004;19:245,254. © 2004 Wiley-Liss, Inc. [source] A novel inorganic hollow fiber membrane reactor for catalytic dehydrogenation of propaneAICHE JOURNAL, Issue 9 2009Zhentao Wu Abstract A novel inorganic hollow fiber membrane reactor (iHFMR) has been developed and applied to the catalytic dehydrogenation of propane to propene. Alumina hollow fiber substrates, prepared by a phase inversion/sintering method, possess a unique asymmetric structure that can be characterized by a very porous inner surface from which finger-like voids extend across ,80% of the fiber cross-section with the remaining 20% consisting of a denser sponge-like outer layer. In contrast to other existing Pd/Ag composite membranes, where an intermediate ,-Al2O3 layer is often used to bridge the Pd/Ag layer and the substrate, the Pd/Ag composite membrane prepared in this study was achieved by coating the Pd/Ag layer directly onto the outer surface of the asymmetric substrate. After depositing submicron-sized Pt (0.5 wt %)/,-alumina catalysts in the finger-like voids of the substrates, a highly compact multifunctional iHFMR was developed. Propane conversion as high as 42% was achieved at the initial stage of the reaction at 723 K. In addition, the space-time yields of the iHFMR were ,60 times higher than that of a fixed bed reactor, demonstrating advantages of using iHFMR for dehydrogenation reactions. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Separation of fatty alcohol ethoxylates by capillary zone electrophoresis and micellar electrokinetic chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 3 2009Ryo Koike Abstract Separation methods based on capillary zone electrophoresis and micellar electrokinetic chromatography were developed to characterize the distribution of ethylene oxide (EO) homologues in the fatty alcohol ethoxylates (FAEs). Prior to the separation, the FAEs were derivatized with 2-fluoro-1-methylpyridinium p -toluenesulfonate (FMPTS) to allow CZE separation and UV detection. To prevent adsorption of cationic analytes onto the inner surface of the capillary and formation of micelles in CZE analysis, a lower pH background solution (BGS) containing a high concentration of acetonitrile was employed. Under optimal conditions, FMPTS-derivatized FAEs with an average EO number of 6 were completely separated within 11 min. For MEKC analysis of the FAEs, dodecyltrimethylammonium chloride (DTAC) was added to the BGS. In the presence of 30 mM DTAC in 10 mM phosphate buffer (pH 2.5) containing 20% (v/v) acetonitrile, superior oligomer separation of the FAEs containing up to 50 EO groups was achieved within 30 min with good analytical reproducibilities. Furthermore, the developed method was applied to the analysis of the FAEs in commercial products such as laundry detergent and fabric softener. [source] Analysis of an antibody pharmaceutical, tocilizumab, by capillary electrophoresis using a carboxylated capillaryJOURNAL OF SEPARATION SCIENCE, JSS, Issue 5 2008Atsushi Taga Abstract Antibody pharmaceuticals are becoming more and more prevalent due to their excellent effectiveness in clinical medications, and are expected to allow tailor-made medical treatment for rheumatic diseases, immunosuppression in cardiac transplantation, and cancer. Antibody-type pharmaceuticals of immunoglobulin G (IgG) commonly have N -glycosylated carbohydrate chains attached to heavy chains. The carbohydrate chains play important roles in the effectiveness of antibodies. Therefore evaluation of a glycosylated species is important in the first step of quality control of antibody pharmaceuticals. In the present work, we examined capillary electrophoresis with a newly developed, chemically modified capillary, the inner surface of which is modified with carboxyl groups, for evaluation of IgG molecular species which have carbohydrate chains; tocilizumab was used as a model. The analytical system developed in the present study is useful for determining the content of non-glycosylated peptides. In the analysis of tocilizumab, the ratio of non-glycosylated peptide was estimated to be 1.23% with a relative standard deviation of 3.05%. The method affords high reproducibility with simple operation, and analysis can be completed within 6 min. [source] Peak shape improvement of basic analytes in capillary liquid chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 3 2005Anja Prüß Abstract The analysis of bases is of special interest in pharmaceutical research because numerous active substances contain basic functional groups. Capillary and conventional size LC separations of drug substances spiked with potential impurities were compared. In the case of the nonpolar drug levonorgestrel equal separation efficiency was readily attained by both techniques. The peaks of basic substances, however, showed extensive tailing when separated by capillary LC. The peak deformation was attributable to interactions of the basic substances with the polar inner surface of the fused silica capillaries employed in capillary LC and does not appear with the steel tubing generally used in conventional size LC. This drawback of capillary LC was overcome by use of deactivated fused silica capillaries for column hardware and transfer lines. [source] | |||||||||||||||||||||||||