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Sample records for benign aqueous biphasic

  1. Metal separations using aqueous biphasic partitioning systems

    SciTech Connect

    Chaiko, D.J.; Zaslavsky, B.; Rollins, A.N.; Vojta, Y.; Gartelmann, J.; Mego, W.

    1996-05-01

    Aqueous biphasic extraction (ABE) processes offer the potential for low-cost, highly selective separations. This countercurrent extraction technique involves selective partitioning of either dissolved solutes or ultrafine particulates between two immiscible aqueous phases. The extraction systems that the authors have studied are generated by combining an aqueous salt solution with an aqueous polymer solution. They have examined a wide range of applications for ABE, including the treatment of solid and liquid nuclear wastes, decontamination of soils, and processing of mineral ores. They have also conducted fundamental studies of solution microstructure using small angle neutron scattering (SANS). In this report they review the physicochemical fundamentals of aqueous biphase formation and discuss the development and scaleup of ABE processes for environmental remediation.

  2. Soil decontamination using aqueous biphasic separation

    SciTech Connect

    Chaiko, D.J.; Mensah-Biney, R.; Gupta, D.

    1994-02-01

    This paper summarizes efforts to develop a biphasic extraction process for separating ultrafine particulate contaminants from soils having high amounts of silt and clay. This work has thus far dealt with the removal of refractory uranium particles from the soils at Fernald, Ohio. The separation process involves the selective partitioning of ultra-fine particles between two immiscible aqueous phases. The authors have conducted batch extraction studies and are now beginning to scaleup the process for pilot-plant testing at Argonne National Laboratory (ANL). The results of these extraction studies are discussed.

  3. AQUEOUS BIPHASE EXTRACTION FOR PROCESSING OF FINE COAL

    SciTech Connect

    K. Osseo-Asare; X. Zeng

    2002-01-01

    The objective of this research project is to develop an aqueous biphase extraction process for the treatment of fine coals. Aqueous biphase extraction is an advanced separation technology that relies on the ability of an aqueous system consisting of a water-soluble polymer and another component, e.g., another polymer, an inorganic salt, or a nonionic surfactant, to separate into two immiscible aqueous phases. The principle behind the partition of solid particles in aqueous biphase systems is the physicochemical interaction between the solid surface and the surrounding liquid solution. In order to remove sulfur and mineral matter from fine coal with aqueous biphasic extraction, it is necessary to know the partitioning behavior of coal, as well as the inorganic mineral components. Therefore, in this research emphasis was placed on the partitioning behavior of fine coal particles as well as model fine inorganic particles in aqueous biphase systems.

  4. Actinide recovery using aqueous biphasic extraction: Initial developmental studies

    SciTech Connect

    Chaiko, D.J.; Mensah-Biney, R.; Mertz, C.J.; Rollins, A.N.

    1992-08-01

    Aqueous biphasic extraction systems are being developed to treat radioactive wastes. The separation technique involves the selective partitioning of either solutes or colloid-size particles between two scible aqueous phases. Wet grinding of plutonium residues to an average particle size of one micron will be used to liberate the plutonium from the bulk of the particle matrix. The goal is to produce a plutonium concentrate that will integrate with existing and developing chemical recovery processes. Ideally, the process would produce a nonTRU waste stream. Coupling physical beneficiation with chemical processing will result in a substantial reduction in the volume of mixed wastes generated from dissolution recovery processes. As part of this program, we will also explore applications of aqueous biphasic extraction that include the separation and recovery of dissolved species such as metal ions and water-soluble organics. The expertise and data generated in this work will form the basis for developing more cost-effective processes for handling waste streams from environmental restoration and waste management activities within the DOE community. This report summarizes the experimental results obtained during the first year of this effort. Experimental efforts were focused on elucidating the surface and solution chemistry variables which govern partitioning behavior of plutonium and silica in aqueous biphasic extraction systems. Additional efforts were directed toward the development of wet grinding methods for producing ultrafine particles with diameters of one micron or less.

  5. Partition of fine particles in aqueous biphase systems

    NASA Astrophysics Data System (ADS)

    Zeng, Xi

    The objective of this research project is to develop an aqueous biphase extraction process for the treatment of fine coals. Aqueous biphase extraction is an advanced separation technology that relies on the ability of an aqueous system consisting of a water-soluble polymer and another component, e.g., another polymer, an inorganic salt, or a nonionic surfactant, to separate into two immiscible aqueous phases. The principle behind the partition of solid particles in aqueous biphase systems is the physicochemical interaction between the solid surface and the surrounding liquid solution. In order to remove sulfur and mineral matter from fine coal with aqueous biphasic extraction, it is necessary to know the partitioning behavior of coal, as well as the inorganic mineral components. Therefore, in this research emphasis was placed on the partitioning behavior of fine coal particles as well as model fine inorganic particles in aqueous biphase systems. In the polyethylene glycol (PEG)/salt/H2O system, it was found that pyrite partition was highly dependent upon pH conditions: at high pH the particles preferred the salt-rich (bottom) phase, while they moved to the polymer-rich (top) phase at low pH. This behavior is attributable to the different surface oxidation products associated with the pH variations: formation of FeOOH in alkaline solution, and a hydrophobic iron-deficient product (Fe 1-xS2) in acidic environment. The partitioning behavior of oxide particles (e.g., Al2O3, Fe2O 3, SiO2, TiO2) in the PEG/Na2SO 4/H2O system indicated that, in the absence of polymer-solid interaction, the surface hydrophilic/hydrophobic properties determined solid partition; otherwise, the specific polymer-solid interaction dominated the distribution of the solid particles. Aside from the polymer/salt aqueous biphase systems, the partitioning behavior of hematite and silica was also investigated in polymer/polymer (PEG/dextran) and polymer/nonionic surfactant (Triton X-100 (TX100

  6. Thermoreversible (Ionic-Liquid-Based) Aqueous Biphasic Systems

    PubMed Central

    Passos, Helena; Luís, Andreia; Coutinho, João A. P.; Freire, Mara G.

    2016-01-01

    The ability to induce reversible phase transitions between homogeneous solutions and biphasic liquid-liquid systems, at pre-defined and suitable operating temperatures, is of crucial relevance in the design of separation processes. Ionic-liquid-based aqueous biphasic systems (IL-based ABS) have demonstrated superior performance as alternative extraction platforms, and their thermoreversible behaviour is here disclosed by the use of protic ILs. The applicability of the temperature-induced phase switching is further demonstrated with the complete extraction of two value-added proteins, achieved in a single-step. It is shown that these temperature-induced mono(bi)phasic systems are significantly more versatile than classical liquid-liquid systems which are constrained by their critical temperatures. IL-based ABS allow to work in a wide range of temperatures and compositions which can be tailored to fit the requirements of a given separation process. PMID:26843320

  7. Thermoreversible (Ionic-Liquid-Based) Aqueous Biphasic Systems

    NASA Astrophysics Data System (ADS)

    Passos, Helena; Luís, Andreia; Coutinho, João A. P.; Freire, Mara G.

    2016-02-01

    The ability to induce reversible phase transitions between homogeneous solutions and biphasic liquid-liquid systems, at pre-defined and suitable operating temperatures, is of crucial relevance in the design of separation processes. Ionic-liquid-based aqueous biphasic systems (IL-based ABS) have demonstrated superior performance as alternative extraction platforms, and their thermoreversible behaviour is here disclosed by the use of protic ILs. The applicability of the temperature-induced phase switching is further demonstrated with the complete extraction of two value-added proteins, achieved in a single-step. It is shown that these temperature-induced mono(bi)phasic systems are significantly more versatile than classical liquid-liquid systems which are constrained by their critical temperatures. IL-based ABS allow to work in a wide range of temperatures and compositions which can be tailored to fit the requirements of a given separation process.

  8. AQUEOUS BIPHASE EXTRACTION FOR PROCESSING OF FINE COAL

    SciTech Connect

    K. Osseo-Asare; X. Zeng

    2001-06-30

    Ever-stringent environmental constraints dictate that future coal cleaning technologies be compatible with micron-size particles. This research program seeks to develop an advanced coal cleaning technology uniquely suited to micron-size particles, i.e., aqueous biphase extraction. The partitioning behaviors of hematite in the dextran (Dex)/Triton X-100 (TX100) and polyethylene glycol (PEG)/dextran systems were investigated and the effects of some ionic surfactants on solid partition were studied. In both biphase systems, the particles stayed in the bottom dextran-rich phase under all pH conditions. This behavior is attributable to the fact that the hydrophilic oxide particles prefer the more hydrophilic bottom phase. Also, the strong favorable interaction between dextran and ferric oxide facilitates the dispersion of the solids in the polysaccharide-rich phase. In the Dex/TX100 system, addition of sodium dodecylsulfate (SDS) or potassium oleate had no effect on the solid partition; on the other hand, addition of dodecyltrimethylammonium bromide (DTAB) transferred the particles to the top phase or interface at high pH values. In the PEG/Dex system, the preferred location of hematite remained the bottom phase in the presence of either SDS or DTAB. The effects of anionic surfactants on the partition behavior are attributable to the fact that they are not able to replace the strongly adsorbed polysaccharide layer on the ferric oxide surface. The results with the cationic surfactant are due to electrostatic interaction between the cationic surfactant and the charged surface of the solid particles. The difference in solids partitioning in the two systems is the result of the different distribution of DTAB in these systems. In the Dex/TX100 system, DTAB prefers the top surfactant-rich phase, while it concentrates in the bottom phase in the PEG/dextran system.

  9. AQUEOUS BIPHASE EXTRACTION FOR PROCESSING OF FINE COAL

    SciTech Connect

    K. Osseo-Asare

    2000-06-02

    Ever-stringent environmental constraints dictate that future coal cleaning technologies be compatible with micron-size particles. This research program seeks to develop an advanced coal cleaning technology uniquely suited to micron-size particles, i.e., aqueous biphase extraction. The partitioning behavior of fly ash in the PEG-2000 Na{sub 2}SO{sub 4}/H{sub 2}O system was studied and the solid in each fraction was characterized by CHN analysis (carbon content), X-ray diffraction (XRD; crystal component), and inductively coupled plasma spectrophotometry (ICP; elemental composition in the ash). In the pH range from 2 to 5, the particles separated into two different layers, i.e., the polymer-rich (top) and salt-rich (bottom) layers. However, above pH 5, the particles in the polymer-rich phase split into two zones. The percent carbon content of the solids in the upper zone ({approximately}80 wt%) was higher than that in the parent sample (63.2 wt%), while the lower zone in the polymer-rich phase had the same percent ash content as the original sample. The particles in the salt-rich phase were mainly composed of ash (with < 4 wt% carbon content). However, when the solid concentration in the whole system increased from 1 wt% to 2 wt%, this 3-fraction phenomenon only occurred above pH 10. XRD results showed that the main crystal components in the ash included quartz, hematite, and mullite. The ICP results showed that Si, Al, and Fe were the major elements in the fly ash, with minor elements of Na, K, Ca, Mg, and Ba. The composition of the ash in the lower zone of the polymer-rich phase remained almost the same as that in the parent fly ash. The largest amount of product ({approximately}60% yield) with the highest carbon content ({approximately}80 wt% C) was obtained in the range pH 6-9. Based on the experimental results obtained, a flowsheet is proposed for the beneficiation of high-carbon fly ash with the aqueous biphase extraction process.

  10. Aqueous biphasic plutonium oxide extraction process with pH and particle control

    DOEpatents

    Chaiko, D.J.; Mensah-Biney, R.

    1997-04-29

    A method is described for simultaneously partitioning a metal oxide and silica from a material containing silica and the metal oxide, using a biphasic aqueous medium having immiscible salt and polymer phases. 2 figs.

  11. Core-shell nanoreactors for efficient aqueous biphasic catalysis.

    PubMed

    Zhang, Xuewei; Cardozo, Andrés F; Chen, Si; Zhang, Wenjing; Julcour, Carine; Lansalot, Muriel; Blanco, Jean-François; Gayet, Florence; Delmas, Henri; Charleux, Bernadette; Manoury, Eric; D'Agosto, Franck; Poli, Rinaldo

    2014-11-17

    Water-borne phosphine-functionalized core-cross-linked micelles (CCM) consisting of a hydrophobic core and a hydrophilic shell were obtained as stable latexes by reversible addition-fragmentation chain transfer (RAFT) in water in a one-pot, three-step process. Initial homogeneous aqueous-phase copolymerization of methacrylic acid (MAA) and poly(ethylene oxide) methyl ether methacrylate (PEOMA) is followed by copolymerization of styrene (S) and 4-diphenylphosphinostyrene (DPPS), yielding P(MAA-co-PEOMA)-b-P(S-co-DPPS) amphiphilic block copolymer micelles (M) by polymerization-induced self-assembly (PISA), and final micellar cross-linking with a mixture of S and diethylene glycol dimethacrylate. The CCM were characterized by dynamic light scattering and NMR spectroscopy to evaluate size, dispersity, stability, and the swelling ability of various organic substrates. Coordination of [Rh(acac)(CO)2 ] (acac=acetylacetonate) to the core-confined phosphine groups was rapid and quantitative. The CCM and M latexes were then used, in combination with [Rh(acac)(CO)2 ], to catalyze the aqueous biphasic hydroformylation of 1-octene, in which they showed high activity, recyclability, protection of the activated Rh center by the polymer scaffold, and low Rh leaching. The CCM latex gave slightly lower catalytic activity but significantly less Rh leaching than the M latex. A control experiment conducted in the presence of the sulfoxantphos ligand pointed to the action of the CCM as catalytic nanoreactors with substrate and product transport into and out of the polymer core, rather than as a surfactant in interfacial catalysis. PMID:25284685

  12. AQUEOUS BIPHASE EXTRACTION FOR PROCESSING OF FINE COAL

    SciTech Connect

    K. Osseo-Asare; X. Zeng

    2001-06-30

    Ever-stringent environmental constraints dictate that future coal cleaning technologies be compatible with micron-size particles. This research program seeks to develop an advanced coal cleaning technology uniquely suited to micron-size particles, i.e., aqueous biphase extraction. The partitioning behaviors of silica in the polyethylene glycol (PEG)/dextran (Dex) and dextran/Triton X-100 (TX100) systems have been investigated, and the effects of sodium dodecylsulfate (SDS) and dodecyltrimethylammonium bromide (DTAB) on solid partition have been studied. In both biphase systems, silica particles stayed in the top PEG-rich phase at low pH. With increase in pH, the particles moved from the top phase to the interface, then to the bottom phase. At very high pH, the solids preferred the top phase again. These trends are attributable to variations in the polymer/solid and nonionic surfactant/solid interactions. Addition of ionic surfactants into these two systems introduces a weakly charged environment, since ionic surfactants concentrate into one phase, either the top phase or the bottom phase. Therefore, coulombic forces also play a key role in the partition of silica particles because electrostatic attractive or repulsive forces are produced between the solid surface and the ionic-surfactant-concentrated phase. For the PEG/dextran system in the presence of SDS, SiO{sub 2} preferred the bottom dextran-rich phase above its pH{sub PZC}. However, addition of DTAB moved the oxide particles from the top phase to the interface, and then to the bottom phase, with increase in pH. These different behaviors are attributable to the fact that SDS and DTAB concentrated into the opposite phase of the PEG/dextran system. On the other hand, in the dextran/Triton X-100 system, both ionic surfactants concentrated in the top surfactant-rich phase and formed mixed micelles with TX100. Therefore, addition of the anionic surfactant, SDS, moved the silica particles from top phase to the

  13. A method for separating water soluble organics from a process stream by aqueous biphasic extraction

    SciTech Connect

    Chaiko, David J.; Mego, William A.

    1997-12-01

    The present invention relates to a method for separating water-miscible organic species from a process stream by aqueous biphasic extraction. In particular, the method includes extracting the organic species into a polymer-rich phase of an aqueous biphase system in which the process stream comprises the salt-rich phase, and, next, separating the polymer from the extracted organic species by contacting the loaded, polymer-rich phase with a water-immiscible organic phase. Alternatively, the polymer can be separated from the extracted organic species by raising the temperature of the loaded, polymer-rich phase above the cloud point, such that the polymer and the water-soluble organic species separate into two distinct aqueous phases. In either case, a substantially salt-free, concentrated aqueous solution containing the organic species is recovered.

  14. Aqueous biphasic extraction process with pH and particle control

    DOEpatents

    Chaiko, David J.; Mensah-Biney, R.

    1995-01-01

    A process for aqueous biphasic extraction of metallic oxides and the like from substances containing silica. Control of media pH enables efficient and effective partition of mixture components. The inventive method may be employed to remove excess silica from kaolin clay.

  15. Aqueous biphasic extraction process with pH and particle control

    DOEpatents

    Chaiko, D.J.; Mensah-Biney, R.

    1995-05-02

    A process for aqueous biphasic extraction of metallic oxides and the like from substances containing silica. Control of media pH enables efficient and effective partition of mixture components. The inventive method may be employed to remove excess silica from kaolin clay. 2 figs.

  16. Aqueous Biphasic Systems Based on Salting-Out Polyethylene Glycol or Ionic Solutions: Strategies for Actinide or Fission Product Separations

    SciTech Connect

    Rogers, Robin D.; Gutowski, Keith E.; Griffin, Scott T.; Holbrey, John D.

    2004-03-29

    Aqueous biphasic systems can be formed by salting-out (with kosmotropic, waterstructuring salts) water soluble polymers (e.g., polyethylene glycol) or aqueous solutions of a wide range of hydrophilic ionic liquids based on imidazolium, pyridinium, phosphonium and ammonium cations. The use of these novel liquid/liquid biphases for separation of actinides or other fission products associated with nuclear wastes (e.g., pertechnetate salts) has been demonstrated and will be described in this presentation.

  17. Method for separating water soluble organics from a process stream by aqueous biphasic extraction

    DOEpatents

    Chaiko, David J.; Mego, William A.

    1999-01-01

    A method for separating water-miscible organic species from a process stream by aqueous biphasic extraction is provided. An aqueous biphase system is generated by contacting a process stream comprised of water, salt, and organic species with an aqueous polymer solution. The organic species transfer from the salt-rich phase to the polymer-rich phase, and the phases are separated. Next, the polymer is recovered from the loaded polymer phase by selectively extracting the polymer into an organic phase at an elevated temperature, while the organic species remain in a substantially salt-free aqueous solution. Alternatively, the polymer is recovered from the loaded polymer by a temperature induced phase separation (cloud point extraction), whereby the polymer and the organic species separate into two distinct solutions. The method for separating water-miscible organic species is applicable to the treatment of industrial wastewater streams, including the extraction and recovery of complexed metal ions from salt solutions, organic contaminants from mineral processing streams, and colorants from spent dye baths.

  18. Aqueous biphasic systems for metal separations : a microcalorimetric analysis of polymer/salt interactions.

    SciTech Connect

    Chaiko, D. J.; Hatton, T. A.; Zaslavsky, B.

    1999-05-03

    Certain radionuclide ions (e.g., TcO{sub 4}{sup 16}) exhibit unusually strong Affinities toward the polymer-rich phase in aqueous biphase systems generated by combinations of salt solutions with polymers such as poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG). Thus, aqueous polymer phases could potentially be used to selectively extract these ions during pretreatment of radioactive tank wastes at Hanford. To help develop a fundamental understanding of the interactions between various ions and polymers in aqueous solution, interaction enthalpies between sodium perrhenate and a random copolymer of PEG and PPG (UCON-50) were measured by microcalorimetric titration. An entropy compensation effect was observed in this system in which changes in enthalpic interactions were balanced by entropy changes such that the interaction free energy remained constant and approximately equal to zero.

  19. Aqueous biphasic extraction of uranium and thorium from contaminated soils. Final report

    SciTech Connect

    Chaiko, D.J.; Gartelmann, J.; Henriksen, J.L.; Krause, T.R.; Deepak; Vojta, Y.; Thuillet, E.; Mertz, C.J.

    1995-07-01

    The aqueous biphasic extraction (ABE) process for soil decontamination involves the selective partitioning of solutes and fine particulates between two immiscible aqueous phases. The biphase system is generated by the appropriate combination of a water-soluble polymer (e.g., polyethlene glycol) with an inorganic salt (e.g., sodium carbonate). Selective partitioning results in 99 to 99.5% of the soil being recovered in the cleaned-soil fraction, while only 0.5 to 1% is recovered in the contaminant concentrate. The ABE process is best suited to the recovery of ultrafine, refractory material from the silt and clay fractions of soils. During continuous countercurrent extraction tests with soil samples from the Fernald Environmental Management Project site (Fernald, OH), particulate thorium was extracted and concentrated between 6- and 16-fold, while the uranium concentration was reduced from about 500 mg/kg to about 77 mg/kg. Carbonate leaching alone was able to reduce the uranium concentration only to 146 mg/kg. Preliminary estimates for treatment costs are approximately $160 per ton of dry soil. A detailed flowsheet of the ABE process is provided.

  20. Lipase in biphasic alginate beads as a biocatalyst for esterification of butyric acid and butanol in aqueous media.

    PubMed

    Ng, Choong Hey; Yang, Kun-Lin

    2016-01-01

    Esterification of organic acids and alcohols in aqueous media is very inefficient due to thermodynamic constraints. However, fermentation processes used to produce organic acids and alcohols are often conducted in aqueous media. To produce esters in aqueous media, biphasic alginate beads with immobilized lipase are developed for in situ esterification of butanol and butyric acid. The biphasic beads contain a solid matrix of calcium alginate and hexadecane together with 5 mg/mL of lipase as the biocatalyst. Hexadecane in the biphasic beads serves as an organic phase to facilitate the esterification reaction. Under optimized conditions, the beads are able to catalyze the production of 0.16 mmol of butyl butyrate from 0.5 mmol of butyric acid and 1.5 mmol of butanol. In contrast, when monophasic beads (without hexadecane) are used, only trace amount of butyl butyrate is produced. One main application of biphasic beads is in simultaneous fermentation and esterification (SFE) because the organic phase inside the beads is very stable and does not leach out into the culture medium. SFE is successfully conducted with an esterification yield of 6.32% using biphasic beads containing iso-octane even though the solvent is proven toxic to the butanol-producing Clostridium spp. PMID:26672465

  1. Role of the Hofmeister series in the formation of ionic-liquid-based aqueous biphasic systems.

    PubMed

    Shahriari, Shahla; Neves, Catarina M S S; Freire, Mara G; Coutinho, João A P

    2012-06-21

    Among the numerous and interesting features of ionic liquids is their ability to form aqueous biphasic systems (ABSs) when combined with inorganic or organic salts in aqueous media. In this work, a wide range of salts was studied, aiming at gathering a detailed picture on the molecular mechanisms that govern the ability of the salt ions to induce the formation of ionic-liquid-based ABSs. For that purpose, 1-butyl-3-methylimidazolium trifluoromethanesulfonate was chosen due to its facility to undergo liquid-liquid demixing in aqueous media containing conventional salts. The corresponding ternary phase diagrams, tie-lines, and tie-line lengths were determined at 298 K and atmospheric pressure. With the large body of data measured in this work, it was possible to establish a scale on the salt cation and anion abilities to induce the formation of ionic-liquid-based ABSs, which follows the Hofmeister series, and to show that the molar entropy of hydration of the salt ions is the driving force for aqueous two-phase system formation. PMID:22594382

  2. Extraction of Biomolecules Using Phosphonium-Based Ionic Liquids + K3PO4 Aqueous Biphasic Systems

    PubMed Central

    Louros, Cláudia L. S.; Cláudio, Ana Filipa M.; Neves, Catarina M. S. S.; Freire, Mara G.; Marrucho, Isabel M.; Pauly, Jérôme; Coutinho, João A. P.

    2010-01-01

    Aqueous biphasic systems (ABS) provide an alternative and efficient approach for the extraction, recovery and purification of biomolecules through their partitioning between two liquid aqueous phases. In this work, the ability of hydrophilic phosphonium-based ionic liquids (ILs) to form ABS with aqueous K3PO4 solutions was evaluated for the first time. Ternary phase diagrams, and respective tie-lines and tie-lines length, formed by distinct phosphonium-based ILs, water, and K3PO4 at 298 K, were measured and are reported. The studied phosphonium-based ILs have shown to be more effective in promoting ABS compared to the imidazolium-based counterparts with similar anions. Moreover, the extractive capability of such systems was assessed for distinct biomolecules (including amino acids, food colourants and alkaloids). Densities and viscosities of both aqueous phases, at the mass fraction compositions used for the biomolecules extraction, were also determined. The evaluated IL-based ABS have been shown to be prospective extraction media, particularly for hydrophobic biomolecules, with several advantages over conventional polymer-inorganic salt ABS. PMID:20480041

  3. Benign cutaneous biphasic hybrid tumor of perineurioma and cellular neurothekeoma: A case report expanding the clinical and histopathologic features of a recently described entity.

    PubMed

    Linos, Konstantinos; Stuart, Lauren; Goncharuk, Victor; Edgar, Mark

    2015-04-01

    Benign cutaneous plexiform hybrid tumor of perineurioma and cellular neurothekeoma (BCPHTPCN) is a recently described entity that presents as a solitary papule in the perioral area. As implied by its name, BCPHTPCN displays microscopic features of both perineurioma and cellular neurothekeoma arranged in a plexiform pattern. We report a case of nonplexiform benign cutaneous biphasic hybrid tumor of perineurioma and cellular neurothekeoma in a 36-year-old woman, who presented with a 4-year history of a firm, flesh-colored left ankle nodule. Histologically, there was a biphasic, well-circumscribed unencapsulated dermal mesenchymal proliferation with no connection to the epidermis, which exhibited mild acanthosis with slightly pigmented basal keratinocytes and overlying parakeratosis. The proliferation consisted of uniform bland spindle cells with bipolar cytoplasmic processes arranged in whorls with interspersed islands of epithelioid cells. Immunohistochemically, the spindle cell component was positive for CD34, EMA, and GLUT-1, consistent with perineurial differentiation, whereas the epithelioid nests were positive for NKI/C3 and MiTF, as expected in neurothekeoma. Stains for S100 protein, SOX10, desmin, claudin, pan-melanoma markers, and NSE were negative. We believe this case expands the histopathologic spectrum of BCPHTPCN showing that it can be grown in a nonplexiform pattern, and we suggest the term benign cutaneous biphasic hybrid tumor of perineurioma and cellular neurothekeoma as a more precise name. It is also, to the best of our knowledge, the first case reported outside the head and neck area. PMID:25229567

  4. INVESTIGATION OF AQUEOUS BIPHASIC SYSTEMS FOR THE SEPARATIONS OF LIGNINS FROM CELLULOSE IN THE PAPER PULPING PROCESS. (R826732)

    EPA Science Inventory

    In efforts to apply a polymer-based aqueous biphasic system (ABS) extraction to the paper pulping process, the study of the distribution of various lignin and cellulosic fractions in ABS and the effects of temperature on system composition and solute partitioning have been inv...

  5. New technetium-99m generator technologies utilizing polyethylene glycol-based aqueous biphasic systems

    SciTech Connect

    Rogers, R.D.; Bond, A.H.; Zhang, Jianhua; Horwitz, P.

    1995-12-31

    Two new schemes for TcO{sub 4}{sup {minus}}/MoO{sub 4}{sup 2{minus}} separations from OH{sup {minus}} and MoO{sub 4}{sup 2{minus}} media using polyethylene glycol (PEG)-based aqueous biphasic systems (ABS) have been developed. The two most important salt solutions in current {sup 99m}Tc-generator technologies, OH{sup {minus}} and MoO{sub 4}{sup 2{minus}}, also salt out PEG to form ABS. In liquid/liquid PEG- ABS, pertechnetate can be separated from molybdate with separation factors as high as 10,000. Stripping is accomplished by reduction of the TcO{sub 4}{sup {minus}} and back extraction into a salt solution. the strip solution can be the salt of an imaging agent (e.g., Na{sub 4}HEDPA) and thus may, under the appropriate conditions, be injected directly into the human body. {sup 99m}TcO{sub 4}{sup {minus}} can also be concentrated from a dilute load solution of {sup 99}MoO{sub 4}{sup 2{minus}} in NaOH using an aqueous biphasic extraction chromatographic technique (ABEC). A rinse with K{sub 2}CO{sub 3} assures that all {sup 99}MoO{sub 4}{sup 2{minus}} is removed from the column and this is confirmed by a rapid drop in {sup 99}Mo activity by the fourth free column volume (fcv) of rinse. The {sup 99m}TcO{sub 4}{sup {minus}} is then eluted with water. This chromatographic separation affords 94% of the {sup 99m}TcO{sub 4}{sup {minus}} activity in 5 fcv, with the y spectrum showing less than 2 {times} 10{sup {minus}4} of the original {sup 99}Mo activity.

  6. (R)-PAC biosynthesis in [BMIM][PF₆]/aqueous biphasic system using Saccharomyces cerevisiae BY4741 cells.

    PubMed

    Kandar, Smita; Suresh, A K; Noronha, Santosh B

    2015-02-01

    (R)-phenylacetylcarbinol or (R)-PAC is a pharmaceutical precursor of (1R, 2S) ephedrine and (1S, 2S) pseudoephedrine. Biotransformation of benzaldehyde and glucose by pyruvate decarboxylase produces (R)-PAC. This biotransformation suffers from toxicity of the substrate, product [(R)-PAC] and by-product (benzyl alcohol). In the present study, ionic liquid/aqueous biphasic system was employed to enhance (R)-PAC production. Fermented broth was the reaction medium in which Saccharomyces cerevisiae BY4741 was the source of pyruvate decarboxylase. Hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) was the non-aqueous phase in which toxic compounds reside. Biocompatibility of [BMIM][PF6] and adequate distribution coefficients of benzaldehyde, (R)-PAC and benzyl alcohol were determined. A Box-Behnken design and response surface methodology were used for the optimization of biotransformation variables in order to maximize (R)-PAC yield and productivity. The results showed higher (R)-PAC yield and productivity of ∼1.5-fold each in the biphasic biotransformation of phase volume ratio 0.05 as compared to the monophasic (conventional) biotransformation. Moreover, the level of major by-product benzyl alcohol was also 3.5-fold lower in biphasic biotransformation. [BMIM][PF6]/aqueous biphasic system is a new approach which could intensify the (R)-PAC production. PMID:25424285

  7. Improved extraction of fluoroquinolones with recyclable ionic-liquid-based aqueous biphasic systems†

    PubMed Central

    Almeida, Hugo F. D.; Freire, Mara G.; Marrucho, Isabel M.

    2016-01-01

    In the past few years, the improvement of advanced analytical tools allowed to confirm the presence of trace amounts of metabolized and unchanged active pharmaceutical ingredients (APIs) in wastewater treatment plants (WWTPs) as well as in freshwater surfaces. It is known that the continuous contact with APIs, even at very low concentrations (ng L−1–μg L−1), leads to serious human health problems. In this context, this work shows the feasibility of using ionic-liquid-based aqueous biphasic systems (IL-based ABS) in the extraction of quinolones present in aqueous media. In particular, ABS composed of imidazolium- and phosphonium-based ILs and aluminium-based salts (already used in water treatment plants) were evaluated in one-step extractions of six fluoroquinolones (FQs), namely ciprofloxacin, enrofloxacin, moxifloxacin, norfloxacin, ofloxacin and sarafloxacin, and extraction efficiencies up to 98% were obtained. Despite the large interest devoted to IL-based ABS as extractive systems of outstanding performance, their recyclability/reusability has seldomly been studied. An efficient extraction/cleaning process of the IL-rich phase is here proposed by FQs induced precipitation. The recycling of the IL and its further reuse without losses in the ABS extractive performance for FQs were established, as confirmed by the four consecutive removal/extraction cycles evaluated. This novel recycling strategy supports IL-based ABS as sustainable and cost-efficient extraction platforms.

  8. Modulating the Solubilities of Ionic Liquid Components in Aqueous-Ionic Liquid Biphasic Systems: A Q-NMR Investigation.

    PubMed

    Atanassova, Maria; Mazan, Valérie; Billard, Isabelle

    2015-06-01

    Aqueous-ionic liquid (A-IL) biphasic systems have been examined in terms of deuterated water, acid, and IL cation and anion mutual solubilities in the upper (water-rich, in mole fraction) and lower phase of aqueous/IL biphasic systems at ambient temperature. The biphasic mixtures were composed of deuterated acids of various concentrations (mainly DCl, DNO(3), and DClO(4) from 10(-2) to 10(-4)  M) and five ionic liquids of the imidazolium family with a hydrophobic anion (CF(3)SO(2))(2) N(-), that is, [C1 Cn im][Tf(2)N], (n=2, 4, 6, 8 and 10). The analytical techniques applied were (1) H NMR, (19) F NMR, Karl-Fischer titration, pH potentiometry for IL cations and anions, and water and acid determination. The effects of the ionic strength (μ=0.1 M NaCl and NaNO(3) as well as μ=0.1 M, 0.2 M and 0.4 M NaClO(4), according to the investigated acid), the nature of the IL cation, and the nature of the mineral acid on the solubilities of the (D(2)O, D(+), Tf(2)N(-), C1 Cn im(+)) entities in the lower or upper phases were determined. The addition of sodium perchlorate was found to enhance the Tf(2)N(-) solubility while inhibiting the solubility of the ionic liquid cation. Differences in IL cation and anion solubilities of up to 42 mM were evidenced. The consequences for the characterization of the aqueous biphasic system, the solvent extraction process of the metal ions, and the ecological impact of the ILs are discussed. PMID:25787248

  9. Simple, benign, aqueous-based amination of polycarbonate surfaces

    DOE PAGESBeta

    VanDelinder, Virginia; Wheeler, David R.; Small, Leo J.; Brumbach, Michael T.; Spoerke, Erik D.; Henderson, Ian; Bachand, George D.

    2015-03-18

    Here we report a simple, safe, environmentally-friendly aqueous method that uses diamines to functionalize a polycarbonate surface with amino groups. We demonstrate the ability of this facile method to serve as a foundation upon which other functionalities may be attached, including anti-fouling coatings and oriented membrane proteins. The use of water as the solvent for the functionalization ensures that solvent induced swelling does not affect the optical or mechanical properties of the polycarbonate.

  10. Direct transformation of xylan-type hemicelluloses to furfural via SnCl₄ catalysts in aqueous and biphasic systems.

    PubMed

    Wang, Wenju; Ren, Junli; Li, Huiling; Deng, Aojie; Sun, Runcang

    2015-05-01

    Direct catalytic transformation of xylan-type hemicelluloses to furfural in the aqueous system and the biphasic system were comparatively investigated under mild conditions. Screening of several promising chlorides for conversion of beech xylan in the aqueous system revealed the Lewis acid SnCl4 was the most effective catalyst. Comparing to the single aqueous system, the bio-based 2-methyltetrahydrofuran (2-MTHF)/H2O biphasic system was more conducive to the synthesis of furfural, in which the highest furfural yield of 78.1% was achieved by using SnCl4 as catalysts under the optimized reaction conditions (150°C, 120 min). Additionally, the influences of xylan-type hemicelluloses with different chemical and structural features from beech, corncob and bagasse on the furfural production were studied. It was found that furfural yield to some extent was determined by the xylose content in hemicelluloses and also had relationships with the molecular weight of hemicelluloses and the degree of crystallization. PMID:25742750

  11. Cell surface energy, contact angles and phase partition. II. Bacterial cells in biphasic aqueous mixtures.

    PubMed

    Gerson, D F; Akit, J

    1980-11-01

    Partition coefficients in biphasic mixtures of poly(ethylene glycol) and Dextran are compared to cell surface energies obtained from contact angles of each liquid phase on cell layers. Linear relationships are observed between these two independent measurements for a variety of bacterial cells. The results demonstrate the importance of interfacial phenomena and contact angles in the phase-partition process. PMID:6159003

  12. Enhanced extraction of bovine serum albumin with aqueous biphasic systems of phosphonium- and ammonium-based ionic liquids.

    PubMed

    Pereira, Matheus M; Pedro, Sónia N; Quental, Maria V; Lima, Álvaro S; Coutinho, João A P; Freire, Mara G

    2015-07-20

    Novel aqueous biphasic systems (ABS) composed of phosphonium- or ammonium-based ionic liquids (ILs), combined with a buffered aqueous solution of potassium citrate/citric acid (pH=7.0), were investigated for the extraction of proteins. For that purpose, the phase diagrams, tie-lines and tie-line lengths were determined at 25 °C, and the performance of these ABS for the extraction of bovine serum albumin (BSA) was then evaluated. The obtained results reveal that, with the exception of the more hydrophobic ILs, most of the systems investigated allow the complete extraction of BSA for the IL-rich phase in a single-step. These remarkable extraction efficiencies are far superior to those afforded by more conventional extraction systems previously reported. The composition of the biphasic systems, i.e., the amount of phase-forming components, was also investigated aiming at reducing the overall costs of the process without losing efficiency on the protein extraction. It is shown that the extraction efficiencies of BSA are maintained at 100% up to high protein concentrations (at least up to 10 g L(-1)). The recovery of the BSA from the IL-rich phase by dialysis is also shown in addition to the demonstration of the IL recyclability and reusability, at least for 3 times. In the sequential three-step extractions (BSA recovery/IL reusability), the extraction efficiencies of BSA for the IL-rich phase were maintained at 100%. For the improved ABS, the preservation of the protein native conformation was confirmed by Size Exclusion High-Performance Liquid Chromatography (used also as the quantification method) and by Fourier Transform Infra-Red spectroscopy. According to the results herein reported, ABS composed of phosphonium- or ammonium-based ILs and a biodegradable organic salt represent an alternative and remarkable platform for the extraction of BSA and may be extended to other proteins of interest. PMID:25865275

  13. Aqueous biphasic systems composed of ionic liquids and polypropylene glycol: insights into their liquid-liquid demixing mechanisms.

    PubMed

    Neves, Catarina M S S; Shahriari, Shahla; Lemus, Jesus; Pereira, Jorge F B; Freire, Mara G; Coutinho, João A P

    2016-07-27

    Novel ternary phase diagrams of aqueous biphasic systems (ABSs) composed of polypropylene glycol with an average molecular weight of 400 g mol(-1) (PPG-400) and a vast number of ionic liquids (ILs) were determined. The large array of selected ILs allowed us to evaluate their tuneable structural features, namely the effect of the anion nature, cation core and cation alkyl side chain length on the phase behaviour. Additional evidence on the molecular-level mechanisms which rule the phase splitting was obtained by (1)H NMR (Nuclear Magnetic Resonance) spectroscopy and by COSMO-RS (Conductor-like Screening Model for Real Solvents). Some systems, for which the IL-PPG-400 pairs are completely miscible, revealed to be of type "0". All data collected suggest that the formation of PPG-IL-based ABSs is controlled by the interactions established between the IL and PPG, contrarily to previous reports where a "salting-out" phenomenon exerted by the IL over the polymer in aqueous media was proposed as the dominant effect in ABS formation. The influence of temperature on the liquid-liquid demixing was also evaluated. In general, an increase in temperature favours the formation of an ABS in agreement with the lower critical solution temperature (LCST) phase behaviour usually observed in polymer-IL binary mixtures. Partition results of a dye (chloroanilic acid, in its neutral form) further confirm the possibility of tailoring the phases' polarities of IL-PPG-based ABSs. PMID:27405841

  14. Aqueous biphasic systems composed of ionic liquids and sodium carbonate as enhanced routes for the extraction of tetracycline.

    PubMed

    Marques, Carlos F C; Mourão, Teresa; Neves, Catarina M S S; Lima, Alvaro S; Boal-Palheiros, Isabel; Coutinho, João A P; Freire, Mara G

    2013-01-01

    Aqueous biphasic systems (ABS) using ionic liquids (ILs) offer an alternative approach for the extraction, recovery, and purification of biomolecules through their partitioning between two aqueous liquid phases. In this work, the ability of a wide range of ILs to form ABS with aqueous solutions of Na2 CO3 was evaluated. The ABS formed by IL + water + Na2 CO3 were determined at 25°C, and the respective solubility curves, tie-lines, and tie-line lengths are reported. The studied ILs share the common chloride anion, allowing the IL cation core, the cation isomerism, the presence of functionalized groups, and alkyl side chain length effects to be evaluated. An increase in the cation side alkyl chain length leads to a higher ability for liquid-liquid demixing whereas different positional isomers and the presence of an allyl group have no major influence in the phase diagrams behavior. Quaternary phosphonium- and ammonium-based fluids are more able to form an ABS when compared with imidazolium-, pyridinium-, pyrrolidinium-, and piperidium-based ILs. Moreover, the presence of an aromatic cation core has no major contribution to the formation of ABS when compared to the respective nonaromatic counterparts. Finally, to appraise on the systems applicability in downstream processing, selected systems were used for the partitioning of tetracyclines (neutral and salt forms) - a class of antibiotics produced by bacteria fermentation. Single-step extraction efficiencies for the IL-rich phase were always higher than 99% and confirm the great potential of ILs to be applied in the biotechnological field. PMID:23420737

  15. Bioproduction of 2-phenylethanol in a biphasic ionic liquid aqueous system.

    PubMed

    Sendovski, Mor; Nir, Netta; Fishman, Ayelet

    2010-02-24

    2-Phenylethanol (PEA) is a commercial flavor and fragrance compound, with a rose-like odor, used in the cosmetics and food industries. Saccharomyces cerevisiae strains produce PEA in a growth-associated manner but are prone to product inhibition, resulting in low production yields. The aim of this study was to use immiscible ionic liquids (ILs) in a biphasic system to enhance the PEA concentration by means of in situ product removal (ISPR). Nine ILs were tested for their influence on growing yeast cells, and five of them were found to be biocompatible. A correlation between the IL structure and the effect on yeast growth was investigated. [Tf(2)N] anions were found to be the most biocompatible in comparison to [PF(6)] and [BF(4)], and the pyridinium and ammonium cations were slightly preferable than the imidazolium cation. Furthermore, the longer the alkyl side chain on the imidazolium ring, the less it is biocompatible, with major significance above six carbons. The five biocompatible ILs were tested for PEA recovery capability by determining their distribution coefficients (K(D)), with the highest value of 17.6 obtained for BMIM[Tf(2)N]. Finally, ILs were tested for their efficiency as ISPR solvents under stress conditions of a high product concentration. A 3-5-fold increase in the total PEA concentration produced by the cells was obtained with MPPyr[Tf(2)N], OMA[Tf(2)N], and BMIM[Tf(2)N], demonstrating the potential of ILs for enhancing productivity in bioprocesses using growing cells. PMID:20095569

  16. Enhanced extraction of proteins using cholinium-based ionic liquids as phase-forming components of aqueous biphasic systems.

    PubMed

    Quental, Maria V; Caban, Magda; Pereira, Matheus M; Stepnowski, Piotr; Coutinho, João A P; Freire, Mara G

    2015-09-01

    Aqueous biphasic systems (ABS) composed of ionic liquids (ILs) are promising platforms for the extraction and purification of proteins. In this work, a series of alternative and biocompatible ABS composed of cholinium-based ILs and polypropylene glycol were investigated. The respective ternary phase diagrams, tie-lines, tie-line lengths and critical points were determined at 25°C. The extraction performance of these systems for commercial bovine serum albumin (BSA) was then evaluated. The stability of BSA at the IL-rich phase was ascertained by size exclusion high-performance liquid chromatography and Fourier transform infrared spectroscopy. Appropriate ILs lead to the complete extraction of BSA for the IL-rich phase, in a single step, while maintaining the protein's native conformation. Furthermore, to evaluate the performance of these systems when applied to real matrices, the extraction of BSA from bovine serum was additionally carried out, revealing that the complete extraction of BSA was maintained and achieved in a single step. The remarkable extraction efficiencies obtained are far superior to those observed with typical polymer-based ABS. Therefore, the proposed ABS may be envisaged as a more effective and biocompatible approach for the separation and purification of other value-added proteins. PMID:25864445

  17. Recoverable and recyclable water-soluble sulphonated salicylaldimine Rh(I) complexes for 1-octene hydroformylation in aqueous biphasic media.

    PubMed

    Matsinha, Leah C; Mapolie, Selwyn F; Smith, Gregory S

    2015-01-21

    A series of water-soluble Rh(i) mononuclear complexes of general formula: [Rh(sulphsal-X-R)(COD)] [sulphsal = sulphonated salicylaldimine, COD = cyclooctadiene; where R = H, Cl, CH3 and X = H, (t)Bu] have been synthesized. All the compounds were characterised using various spectroscopic and analytical techniques such as nuclear magnetic resonance spectroscopy, infrared spectroscopy, single crystal X-ray diffraction (for complex ) and mass spectrometry. All the compounds display excellent water-solubility at room temperature and were tested as catalyst precursors in the aqueous biphasic hydroformylation of 1-octene. The catalysts could be easily recovered by phase separation and were used up to 5 times without any significant loss in activity and 1-octene conversion. Very high yields of the expected aldehydes were obtained without addition of any phase transfer agents, co-solvents or hydrophobic ligands. Excellent aldehyde chemoselectivity is observed for all the catalysts but this varied each time the catalysts were recycled, with the formation of a small amount of internal olefins. ICP-OES and mercury poisoning experiments show that a combination of homogeneous catalysis and catalysis mediated by nanoparticles is taking place in these systems. PMID:25415263

  18. Ionic liquid-based aqueous biphasic systems as a versatile tool for the recovery of antioxidant compounds.

    PubMed

    Santos, João H; e Silva, Francisca A; Ventura, Sónia P M; Coutinho, João A P; de Souza, Ranyere L; Soares, Cleide M F; Lima, Álvaro S

    2015-01-01

    The comparative evaluation of distinct types of ionic liquid-based aqueous biphasic systems (IL-ABS) and more conventional polymer/salt-based ABS to the extraction of two antioxidants, eugenol and propyl gallate, is focused. In a first approach, IL-ABS composed of ILs and potassium citrate (C6H5K3O7/C6H8O7) buffer at pH 7 were applied to the extraction of two antioxidants, enabling the assessment of the impact of IL cation core on the extraction. The second approach uses ABS composed of polyethylene glycol (PEG) and potassium phosphate (K2HPO4/KH2PO4) buffer at pH 7 with imidazolium-based ILs as adjuvants. Their application to the extraction of the compounds allowed the investigation of the impact of the presence/absence of IL, the PEG molecular weight, and the alkyl side chain length of the imidazolium cation on the partition. It is possible to maximize the extractive performance of both antioxidants up to 100% using both types of IL-ABS. The IL enhances the performance of ABS technology. The data puts in evidence the pivotal role of the appropriate selection of the ABS components and design to develop a successful extractive process, from both environmental and performance points of view. PMID:25311237

  19. One-step extraction and concentration of estrogens for an adequate monitoring of wastewater using ionic-liquid-based aqueous biphasic systems†

    PubMed Central

    Lima, Diana L. D.; Esteves, Valdemar I.; Coutinho, João A. P.; Freire, Mara G.

    2015-01-01

    Ethinylestradiol (EE2) is a synthetic hormone that has been recognized as one of the most prominent endocrine disruptors found in the aqueous environment. Nevertheless, the low content of EE2 in wastewater makes its identification/quantification unfeasible – a major drawback for the evaluation of its persistence and environmental impact. In this context, a novel extraction/concentration method for EE2 from wastewater is proposed here based on aqueous biphasic systems composed of ionic liquids (ILs). Aqueous biphasic systems formed by several hydrophilic ILs and KNaC4H4O6 were initially screened and optimized, with extraction efficiencies of EE2 for the IL-rich phase ranging between 92 and 100%. Remarkable results were obtained with systems that allow the complete extraction of EE2 in a single-step, and without loss of EE2 or the saturation of the extractive phase. Further, the concentration factors of EE2 attainable with these systems were investigated by a suitable manipulation of the composition of the phase-forming components and the corresponding volumes of the coexisting phases. An outstanding concentration of EE2 up to 1000-fold (from ng L−1 to μg L−1) in a single extraction and concentration step was achieved for the first time with IL-based aqueous biphasic systems. These systems are straightforwardly envisaged for the monitoring of wastewater as one-step extraction and concentration routes for a wide array of endocrine disrupting chemicals while allowing an adequate evaluation of their environmental impact. PMID:26379470

  20. Partitioning of amino acids in the aqueous biphasic system containing the water-miscible ionic liquid 1-butyl-3-methylimidazolium bromide and the water-structuring salt potassium citrate.

    PubMed

    Zafarani-Moattar, Mohammed Taghi; Hamzehzadeh, Sholeh

    2011-07-01

    In biotechnology, extraction by means of aqueous biphasic systems (ABS) is known as a promising tool for the recovery and purification of bio-molecules. Over the past decade, the increasing emphasis on cleaner and environmentally benign extraction procedures has led to enhanced interest in the ABS containing ionic liquids (ILs)-a new class of non-volatile alternative solvents. ABS composed of the hydrophilic IL {1-butyl-3-methylimidazolium bromide ([C4 mim]Br)} and potassium citrate-which is easily degraded-represents a clean media to green separation of bio-molecules. In this regard, here, the extraction capability of this ABS was evaluated through its application to the extraction of some amino acids. To gain an insight into the driving forces of amino acid partitioning in the studied IL-based ABS, the distribution of five model amino acids (L-tryptophan, L-phenylalanine, L-tyrosine, L-leucine, and L-valine) at different aqueous medium pH values and different phase compositions was investigated. The studies indicated that hydrophobic interactions were the main driving force, although electrostatic interactions and salting-out effects were also important for the transfer of the amino acids. Moreover, based on the statistical analysis of the driving forces of amino acid partitioning in the studied IL-based ABS, a model was established to describe the partition coefficient of three model amino acids, L-tryptophan, L-phenylalanine, and L-valine, and employed to predict the partition coefficient of two other model amino acids, L-tyrosine and L-leucine. PMID:21509956

  1. Liquid-Phase Synthesis of Ba2V2O7 Phosphor Powders and Films Using Immiscible Biphasic Organic-Aqueous Systems.

    PubMed

    Takahashi, Mami; Hagiwara, Manabu; Fujihara, Shinobu

    2016-08-15

    A liquid-phase synthesis of inorganic phosphor materials at a moderate temperature was proposed by using immiscible liquid-liquid biphasic systems. A self-activated Ba2V2O7 phosphor was actually synthesized from vanadium alkoxide dissolved in an organic solution and barium acetate in an aqueous solution. A mild hydrolysis reaction of the alkoxide started at the organic-inorganic interface, and an intermediate compound, Ba(VO3)2·H2O, was initially formed. Ba2V2O7 powders were then obtained by the conversion from Ba(VO3)2·H2O promoted in the aqueous solution. Ba2V2O7 films were obtained on surface-modified silica glass substrates through the similar chemical reactions. Factors such as the surface state of substrates, the kind of organic solvents, and the volume of aqueous solutions were examined to improve the film deposition behavior. The resultant Ba2V2O7 materials showed broad-band visible photoluminescence upon irradiation with ultraviolet light based on the charge transfer transition in the VO4(3-) units existing as dimers. PMID:27472450

  2. Alternative (Potentially Green) Separations Media: Aqueous Biphasic and Related Systems Extending the Frontier Final Report For Period September 1, 2002 January 31, 2007

    SciTech Connect

    Rogers, Robin D

    2007-06-25

    Through the current DoE-BES funding, we have extended our fundamental understanding of the critical phase separation of aqueous polymer solutions at the molecular level, and have developed a similar understanding of their application as novel solvent systems. Our principal aims included mode of delivery of the aqueous biphasic system (ABS) solvent system and the application of this system to problems of reactive extraction. In the former case we have developed novel solid phase analogues, in the form of cross-linked polyethylene glycol hydrogels, and in the latter case we have examined the role that ABS might play in reaction engineering, with a view to greener, simpler, and safer processes. We have also developed a new salt/salt ABS and have extended our understanding of this system as well. The major outcomes are as follows: (1) Through the use of variable temperature phase diagrams, coupled with differential scanning calorimetry (DSC) measurements of the phases, a better understanding of the thermodynamics of phase formation was obtained. Evidence to the existence and role of an upper critical solution temperature (UCST) or lower critical solution temperature (LCST) (or both) in these systems was gained. With variable temperature solute partitioning, thermodynamic parameters were calculated, and inter-system comparisons were made. Through the use of Abraham's linear solvation energy regression (LSER) the solvent-solute properties of liquid/liquid ABS were examined. We have shown that ABS are indeed very tunable and LSERs have been used as a tool to compare these systems to traditional organic/water and other liquid/liquid systems. (2) We have successfully shown the development of novel reaction media for chemical synthesis and reaction; Aqueous Biphasic Reactive Extraction (ABRE). As a proof of concept, we have shown the synthesis of adipic acid from cyclohexene in an ABS, which represents an important development in the exploitation of this technology. Previous

  3. Optimization of Aqueous Biphasic Tumor Spheroid Microtechnology for Anti-Cancer Drug Testing in 3D Culture

    PubMed Central

    Lemmo, Stephanie; Atefi, Ehsan; Luker, Gary D.; Tavana, Hossein

    2014-01-01

    Tumor spheroids are three-dimensional clusters of cancer cells that exhibit characteristics of poorly perfused tumors and hence present a relevant model for testing the efficacy of anti-cancer compounds. The use of spheroids for drug screening is hindered by technological complexities for high throughput generation of consistent size spheroids individually addressable by drug compounds. Here we present and optimize a simple spheroid technology based on the use of an aqueous two-phase system. Cancer cells confined in a drop of the denser aqueous dextran phase are robotically dispensed into a microwell containing the immersion aqueous polyethylene glycol phase. Cells remain within the drop and form a viable spheroid, without a need for any external stimuli. The size of resulting spheroids is sensitive to volume variations of dispensed drops from the air displacement pipetting head of a commercial liquid handling robot. Therefore, we parametrically optimize the process of dispensing of dextran phase drops. For a given cell density, this optimization reproducibly generates consistent size spheroids in standard 96-well plates. In addition, we evaluate the use of a commercial biochemical assay to examine cellular viability of cancer cell spheroids. Spheroids show a dose-dependent response to cisplatin similar to a monolayer culture. However unlike their two-dimensional counterpart, spheroids exhibit resistance to paclitaxel treatment. This technology, which uses only commercially-available reagents and equipment, can potentially expedite anti-cancer drug discovery. Although the use of robotics makes the ATPS spheroid technology particularly useful for drug screening applications, this approach is compatible with simpler liquid handling techniques such as manual micropipetting and offers a straightforward method of 3D cell culture in research laboratories. PMID:25221631

  4. An Environmentally Benign Protocol for Aqueous Synthesis of Tetrahydrobenzo[b]Pyrans Catalyzed by Cost-Effective Ionic Liquid

    PubMed Central

    Hu, Huanan; Qiu, Fangli; Ying, Anguo; Yang, Jianguo; Meng, Haiping

    2014-01-01

    A mild, efficient, and environmentally benign protocol for the synthesis of tetrahydrobenzo[b]pyran derivatives in the presence of readily accessible, biodegradable, and choline hydroxide based ionic liquid as catalyst has been established. The key features of the reported methodology include good to excellent yields of desired products, simple work-up procedure and good recyclability of catalysts, which may be a practical alternative to the existing conventional processes for the preparation of 4-H pyrans to cater to the requirements of academia as well as industry. PMID:24758931

  5. Accumulation of zirconium phosphate by a Serratia sp.: a benign system for the removal of radionuclides from aqueous flows.

    PubMed

    Mennan, Claire; Paterson-Beedle, Marion; Macaskie, Lynne E

    2010-10-01

    Metal phosphate deposited enzymatically on Serratia sp. has been used successfully for the removal of radionuclides from aqueous flows. Previous studies using biogenic hydrogen uranyl phosphate (HUP) on Serratia sp. biofilm showed removal of 100% of (90)Sr, (137)Cs, and (60)Co via their intercalation into biogenic HUP crystals. Zirconium phosphates (ZrP) offer a potential non-toxic and non-radioactive alternative to HUP for water decontamination. A method was developed for biomanufacturing ZrP. Biogenic ZrP removed ca. 100% of Sr(2+) and Co(2+) (0.5 mM) from solutions to a molar ratio at saturation of ca. 1:0.6 for both Zr:Sr and Zr:Co. The potential for drinking water decontamination via bio-ZrP is discussed with respect to bio-HUP and also other commercially available materials. PMID:20495949

  6. Biphasic catalysis in water/carbon dioxide micellar systems

    DOEpatents

    Jacobson, Gunilla B.; Tumas, William; Johnston, Keith P.

    2002-01-01

    A process is provided for catalyzing an organic reaction to form a reaction product by placing reactants and a catalyst for the organic reaction, the catalyst of a metal complex and at least one ligand soluble within one of the phases of said aqueous biphasic system, within an aqueous biphasic system including a water phase, a dense phase fluid, and a surfactant adapted for forming an emulsion or microemulsion within the aqueous biphasic system, the reactants soluble within one of the phases of the aqueous biphasic system and convertible in the presence of the catalyst to a product having low solubility in the phase in which the catalyst is soluble; and, maintaining the aqueous biphasic system under pressures, at temperatures, and for a period of time sufficient for the organic reaction to occur and form the reaction product and to maintain sufficient density on the dense phase fluid, the reaction product characterized as having low solubility in the phase in which the catalyst is soluble.

  7. Production, Purification, and Identification of Cholest-4-en-3-one Produced by Cholesterol Oxidase from Rhodococcus sp. in Aqueous/Organic Biphasic System

    PubMed Central

    Wu, Ke; Li, Wei; Song, Jianrui; Li, Tao

    2015-01-01

    Cholest-4-en-3-one has positive uses against obesity, liver disease, and keratinization. It can be applied in the synthesis of steroid drugs as well. Most related studies are focused on preparation of cholest-4-en-3-one by using whole cells as catalysts, but production of high-quality cholest-4-en-3-one directly from cholesterol oxidase (COD) using an aqueous/organic two-phase system has been rarely explored. This study set up an enzymatic reaction system to produce cholest-4-en-3-one. We developed and optimized the enzymatic reaction system using COD from COX5-6 (a strain of Rhodococcus) instead of whole-cell biocatalyst. This not only simplifies and accelerates the production but also benefits the subsequent separation and purification process. Through extraction, washing, evaporation, column chromatography, and recrystallization, we got cholest-4-en-3-one with purity of 99.78%, which was identified by nuclear magnetic resonance, mass spectroscopy, and infrared spectroscopy. In addition, this optimized process of cholest-4-en-3-one production and purification can be easily scaled up for industrial production, which can largely decrease the cost and guarantee the purity of the product. PMID:25733914

  8. Oscillatory Motion of a Bi-Phasic Slug in a Teflon Reactor

    NASA Astrophysics Data System (ADS)

    Abolhasani, Milad; Jensen, Klavs

    2015-11-01

    Bi-phasic physical/chemical processes require transfer of solute/reagent molecules across the interface. Continuous multi-phase flow approaches (using gas as the continuous phase), usually fail in providing sufficient interfacial area for transfer of molecules between the aqueous and organic phases. In continuous segmented flow platforms (with a fluorinated polymer-based reactor), the higher surface tension of the aqueous phase compared to the organic phase of a bi-phasic slug, in combination with the low surface energy of the reactor wall result in a more facile motion of the aqueous phase. Thus, upon applying a pressure gradient across the bi-phasic slug, the aqueous phase of the slug moves through the organic phase and leads the bi-phasic slug, thereby limiting the available interfacial area for the bi-phasic mass transfer only to the semi-spherical interface between the two phases. Disrupting the quasi-equilibrium state of the bi-phasic slug through reversing the pressure gradient across the bi-phasic slug causes the aqueous phase to move back through the organic phase. In this work, we experimentally investigate the dynamics of periodic alteration of the pressure gradient across a bi-phasic slug, and characterize the resulting enhanced interfacial area on the bi-phasic mass transfer rate. We demonstrate the enhanced mass transfer rate of the oscillatory flow strategy compared to the continuous multi-phase approach using bi-phasic Pd catalyzed carbon-carbon and carbon-nitrogen cross coupling reactions. NSERC Postdoctoral Fellowship, Novartis Center for Continuous Manufacturing.

  9. Anthemis xylopoda flowers aqueous extract assisted in situ green synthesis of Cu nanoparticles supported on natural Natrolite zeolite for N-formylation of amines at room temperature under environmentally benign reaction conditions.

    PubMed

    Nasrollahzadeh, Mahmoud; Sajadi, S Mohammad; Hatamifard, Arezo

    2015-12-15

    Zeolites, which are nontoxic, abundant, and cheap, are very promising supports for the design and preparation of new and environmentally benign catalysts. In this study, Cu nanoparticles (NPs) were immobilized on the surface of natural Natrolite zeolite by Anthemis xylopoda flowers aqueous extract as a reducing and stabilizing agent. Afterward, the catalytic performance of the prepared catalyst was investigated for N-formylation of amines at room temperature under environmentally benign reaction conditions. The catalyst could be reused at least 5 times without any decrease in activity. The advantages of the present protocol include the use of green catalyst, easy isolation of the products, reusability of catalyst, absence of nontoxic reagents, and excellent yield of the products. PMID:26319331

  10. Asymmetry In Biphase Data Signals

    NASA Technical Reports Server (NTRS)

    Nguyen, Tien M.

    1992-01-01

    Report presents analysis of some effects of asymmetry in Manchester (biphase) binary data signal transmitted by phase modulation of sinusoidal carrier signal. Report extends analysis described in article, "Effects of Asymmetry of NRZ Data Signals on Performance" (NPO-18261), to include case where data biphase-modulated directly on residual carrier.

  11. Mesothelioma - benign-fibrous

    MedlinePlus

    Mesothelioma - benign; Mesothelioma - fibrous; Pleural fibroma; Solitary fibrous tumor of the pleura ... other reasons. Other tests that may show benign mesothelioma include: CT scan of the chest Open lung ...

  12. Biphasic nature of gastric emptying.

    PubMed

    Siegel, J A; Urbain, J L; Adler, L P; Charkes, N D; Maurer, A H; Krevsky, B; Knight, L C; Fisher, R S; Malmud, L S

    1988-01-01

    The existence of a lag phase during the gastric emptying of solid foods is controversial. It has been hypothesised that among other early events, the stomach requires a period of time to process solid food to particles small enough to be handled as a liquid. At present no standardised curve fitting techniques exist for the characterisation and quantification of the lag phase or the emptying rate of solids and liquids. We have evaluated the ability of a modified power exponential function to define the emptying parameters of two different solid meals. Dual labelled meals were administered to 24 normal volunteers. The subjects received meals consisting of either Tc-99m in vivo labelled chicken liver or Tc-99m-egg, which have different densities, and In-111-DTPA in water. The emptying curves were biphasic in nature. For solids, this represented an initial delay in emptying or lag phase followed by an equilibrium emptying phase characterised by a constant rate of emptying. The curves were analysed using a modified power exponential function of the form y(t) = 1-(1-e-kt)beta, where y(t) is the fractional meal retention at time t, k is the gastric emptying rate in min-1, and beta is the extrapolated y-intercept from the terminal portion of the curve. The length of the lag phase and half-emptying time increased with solid food density (31 +/- 8 min and 77.6 +/- 11.2 min for egg and 62 +/- 16 min and 94.1 +/- 14.2 min for chicken liver, respectively). After the lag phase, both solids had similar emptying rates, and these rates were identical to those of the liquids. In vitro experiments indicated that the egg meal disintegrated much more rapidly than the chicken liver under mechanical agitation in gastric juice, lending further support to the hypothesis that the initial lag in emptying of solid food is due to the processing of food into particles small enough to pass the pylorus. We conclude that the modified power exponential model permits characterisation of the biphasic

  13. An effective biphase system accelerates hesperidinase-catalyzed conversion of rutin to isoquercitrin

    PubMed Central

    Wang, Jun; Gong, An; Yang, Cai-Feng; Bao, Qi; Shi, Xin-Yi; Han, Bei-Bei; Wu, Xiang-Yang; Wu, Fu-An

    2015-01-01

    Isoquercitrin is a rare, natural ingredient with several biological activities that is a key precursor for the synthesis of enzymatically modified isoquercitrin (EMIQ). The enzymatic production of isoquercitrin from rutin catalyzed by hesperidinase is feasible; however, the bioprocess is hindered by low substrate concentration and a long reaction time. Thus, a novel biphase system consisting of [Bmim][BF4]:glycine-sodium hydroxide (pH 9) (10:90, v/v) and glyceryl triacetate (1:1, v/v) was initially established for isoquercitrin production. The biotransformation product was identified using liquid chromatography-mass spectrometry, and the bonding mechanism of the enzyme and substrate was inferred using circular dichroism spectra and kinetic parameters. The highest rutin conversion of 99.5% and isoquercitrin yield of 93.9% were obtained after 3 h. The reaction route is environmentally benign and mild, and the biphase system could be reused. The substrate concentration was increased 2.6-fold, the reaction time was reduced to three tenths the original time. The three-dimensional structure of hesperidinase was changed in the biphase system, which α-helix and random content were reduced and β-sheet content was increased. Thus, the developed biphase system can effectively strengthen the hesperidinase-catalyzed synthesis of isoquercitrin with high yield. PMID:25731802

  14. An effective biphase system accelerates hesperidinase-catalyzed conversion of rutin to isoquercitrin.

    PubMed

    Wang, Jun; Gong, An; Yang, Cai-Feng; Bao, Qi; Shi, Xin-Yi; Han, Bei-Bei; Wu, Xiang-Yang; Wu, Fu-An

    2015-01-01

    Isoquercitrin is a rare, natural ingredient with several biological activities that is a key precursor for the synthesis of enzymatically modified isoquercitrin (EMIQ). The enzymatic production of isoquercitrin from rutin catalyzed by hesperidinase is feasible; however, the bioprocess is hindered by low substrate concentration and a long reaction time. Thus, a novel biphase system consisting of [Bmim][BF4]:glycine-sodium hydroxide (pH 9) (10:90, v/v) and glyceryl triacetate (1:1, v/v) was initially established for isoquercitrin production. The biotransformation product was identified using liquid chromatography-mass spectrometry, and the bonding mechanism of the enzyme and substrate was inferred using circular dichroism spectra and kinetic parameters. The highest rutin conversion of 99.5% and isoquercitrin yield of 93.9% were obtained after 3 h. The reaction route is environmentally benign and mild, and the biphase system could be reused. The substrate concentration was increased 2.6-fold, the reaction time was reduced to three tenths the original time. The three-dimensional structure of hesperidinase was changed in the biphase system, which α-helix and random content were reduced and β-sheet content was increased. Thus, the developed biphase system can effectively strengthen the hesperidinase-catalyzed synthesis of isoquercitrin with high yield. PMID:25731802

  15. Biphasic calcium phosphate in periapical surgery

    PubMed Central

    Suneelkumar, Chinni; Datta, Krithika; Srinivasan, Manali R; Kumar, Sampath T

    2008-01-01

    Calcium phosphate ceramics like hydroxyapatite and β -tricalcium phosphate (β -TCP) possess mineral composition that closely resembles that of the bone. They can be good bone substitutes due to their excellent biocompatibility. Biphasic calcium phosphate is a bone substitute which is a mixture of hydroxyapatite and β -tricalcium phosphate in fixed ratios. Studies have demonstrated the osteoconductive potential of this composition. This paper highlights the clinical use of biphasic calcium phosphate as a bone substitute in periapical surgery. PMID:20142892

  16. Acute Biphasic Effects of Ayahuasca

    PubMed Central

    Schenberg, Eduardo Ekman; Alexandre, João Felipe Morel; Filev, Renato; Cravo, Andre Mascioli; Sato, João Ricardo; Muthukumaraswamy, Suresh D.; Yonamine, Maurício; Waguespack, Marian; Lomnicka, Izabela; Barker, Steven A.; da Silveira, Dartiu Xavier

    2015-01-01

    Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca's compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8–13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30–50 and 50–100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca’s chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it's potential therapeutic effects is offered. PMID:26421727

  17. Acute Biphasic Effects of Ayahuasca.

    PubMed

    Schenberg, Eduardo Ekman; Alexandre, João Felipe Morel; Filev, Renato; Cravo, Andre Mascioli; Sato, João Ricardo; Muthukumaraswamy, Suresh D; Yonamine, Maurício; Waguespack, Marian; Lomnicka, Izabela; Barker, Steven A; da Silveira, Dartiu Xavier

    2015-01-01

    Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca's compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8-13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30-50 and 50-100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca's chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it's potential therapeutic effects is offered. PMID:26421727

  18. Anti-prelog reduction of prochiral carbonyl compounds by Oenococcus oeni in a biphasic system.

    PubMed

    Hu, Jian; Xu, Yan

    2006-07-01

    An aqueous-organic biphasic system was established and used with whole cells of Oenococcus oeni to reduce 2-octanone to (R)-2-octanol. The conversion reached 99% when the Tris/borate buffer was increased from 50 mM to 300 mM in the aqueous phase. In addition, the conversion increased as the log P value of the organic solvent changed from 0.5 to 6.6. Under optimized conditions, the conversion of (R)-2-octanol reached 99% from 0.5 M 2-octanone with an optical purity of 99% e.e. The biphasic system allows the anti-Prelog reduction of aliphatic and aromatic ketones to furnish (R)-configurated alcohols in high optical purity as well. PMID:16794770

  19. Exophytic benign prostatic hyperplasia.

    PubMed

    Blaschko, Sarah D; Eisenberg, Michael L

    2011-08-01

    A 60-year-old man had incidental finding of a multilobular 8 × 7 × 7-cm mass identified posterior to the urinary bladder in continuity with the prostate. The man's prostate-specific antigen was 1.87, and he denied any lower urinary tract symptoms. A transrectal ultrasound-guided biopsy demonstrated benign prostatic tissue. A computed tomography-guided needle aspiration demonstrated a benign epithelium-lined cyst, likely prostatic in origin. Benign prostatic hyperplasia is a proliferation of prostatic epithelial and stromal cells. Although prostatic hyperplasia is usually restricted to the prostate gland, hyperplastic nodules occasionally protrude outside the prostate and rarely form exophytic pelvic masses. PMID:20869104

  20. Benign prostate hyperplasia (BPH) - resources

    MedlinePlus

    Resources - benign prostatic hyperplasia (BPH); Prostate enlargement resources; BPH resources ... organizations provide information on benign prostatic hyperplasia ( prostate enlargement ): National Kidney and Urologic Diseases Information Clearinghouse -- www. ...

  1. The Benign Hamburger.

    ERIC Educational Resources Information Center

    Peaslee, Graham; Lantz, Juliette M.; Walczak, Mary M.

    1998-01-01

    Uses a case study of food poisoning from hamburgers at the fictitious Jill-at-the-Grill to teach the nuclear science behind food irradiation. Includes case teaching notes on the benign hamburger. (ASK)

  2. Benign positional vertigo

    MedlinePlus

    ... Clinical practice guideline: Benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg . 2008;139(5 Suppl 4):S47-S81. ... BH, Lund V, et al, eds. Cummings Otolaryngology: Head & Neck Surgery . 6th ed. Philadelphia, PA: Elsevier Mosby; 2015: ...

  3. Benign Essential Blepharospasm

    MedlinePlus

    ... Clinical Trials Organizations Column1 Column2 Benign Essential Blepharospasm Research Foundation 637 North 7th Street Suite 102 P.O. ... 832-0788 Fax: 409-832-0890 Dystonia Medical Research Foundation 1 East Wacker Drive Suite 2810 Chicago, IL ...

  4. Benign bone tumors.

    PubMed

    Gilday, D L; Ash, J M

    1976-01-01

    There is little information in the literature concerning the role of bone scanning in benign bone neoplasms except for sporadic reports. Since the advent of 99mTc-polyphosphate, bone imaging has proven feasible and useful in locating the cause of bone pain, such as in osteoid osteomas, which are not always radiologically apparent, and in evaluating whether or not a radiologic lesion is indeed benign and solitary. Blood-pool images are particularly important in neoplastic disease, since the absence of hyperemia in the immediate postinjection period favors the diagnosis of a benign neoplasm, as does low-grade uptake on the delayed study. The scan, including pinhole magnification images, is especially valuable in diagnosing lesions in the spine and pelvis, which are poorly seen radiologically. We have studied various types of benign bone tumors, including simple and aneurysmal bone cysts, fibrous cortical defects, and nonossifying fibromas, all of which had minimal or no increased uptake of the radiopharmaceutical, unless traumatized. Although osteochondromas and enchondromas showed varied accumulation of activity, the scan was useful in differentiating these from sarcomatous lesions. All osteoid osteomas demonstrated marked activity, and could be accurately located preoperatively, as could the extent of fibrous dysplasia. The bone scan in the reticuloses also showed abnormal accumulation of activity, and aided in arriving at the prognosis and treatment of histiocytic bone lesions. PMID:1082170

  5. Characterizing liquid redistribution in a biphasic vibrating vocal fold using finite element analysis

    PubMed Central

    Kvit, Anton A.; Devine, Erin E.; Vamos, Andrew C.; Tao, Chao; Jiang, Jack J.

    2015-01-01

    OBJECTIVE Vocal fold tissue is biphasic and consists of a solid extracellular matric skeleton swelled with interstitial fluid. Interactions between the liquid and solid impact the material properties and stress response of the tissue. The objective of this study was to model the movement of liquid during vocal fold vibration and estimate the volume of liquid accumulation and stress experienced by the tissue near the anterior-posterior midline, where benign lesions are observed to form. METHODS A three-dimensional biphasic finite element model of a single vocal fold was built to solve for the liquid velocity, pore pressure, and von Mises stress during and just after vibration using the commercial finite element software COMSOL Multiphysics (Version 4.3a, 2013, Structural Mechanics and Subsurface Flow Modules). Vibration was induced by applying direct-load pressures to the subglottal and intraglottal surfaces. Pressure ranges, frequency and material parameters were chosen based on those reported in the literature. Post-processing included liquid velocity, pore pressure and von Mises stress calculations, as well as the frequency-stress and amplitude-stress relationships. RESULTS Resulting time-averaged velocity vectors during vibration indicated liquid movement towards the midline of the fold, as upwards movement in the inferior-superior direction. Pore pressure and von Misses stresses were higher in this region just following vibration. A linear relationship was found between the amplitude and pore pressure, while a nonlinear relationship was found between the frequency and pore pressure. CONCLUSIONS While this study had certain computational simplifications, it is the first biphasic finite element model to employ a realistic geometry and demonstrated the ability to characterize liquid movement due to vibration. Results indicate that there is a significant amount of liquid that accumulates at the midline, however the role of this accumulation still requires

  6. Biomimetic biphasic scaffolds for osteochondral defect repair

    PubMed Central

    Li, Xuezhou; Ding, Jianxun; Wang, Jincheng; Zhuang, Xiuli; Chen, Xuesi

    2015-01-01

    The osteochondral defects caused by vigorous trauma or physical disease are difficult to be managed. Tissue engineering provides a possible option to regenerate the damaged osteochondral tissues. For osteochondral reconstruction, one intact scaffold should be considered to support the regeneration of both cartilage and subchondral bone. Therefore, the biphasic scaffolds with the mimic structures of osteochondral tissues have been developed to close this chasm. A variety of biomimetic bilayer scaffolds fabricated from natural or synthetic polymers, or the ones loading with growth factors, cells, or both of them make great progresses in osteochondral defect repair. In this review, the preparation and in vitro and/or in vivo verification of bioinspired biphasic scaffolds are summarized and discussed, as well as the prospect is predicted. PMID:26816644

  7. Structure and dynamics of biphasic colloidal mixtures.

    PubMed

    Mohraz, Ali; Weeks, Eric R; Lewis, Jennifer A

    2008-06-01

    We investigate the structure and dynamics of biphasic colloidal mixtures composed of coexisting attractive and repulsive microspheres by confocal microscopy. Attractive gels formed in the presence of repulsive microspheres are more spatially homogeneous and, on average, are both more locally tenuous and have fewer large voids than their unary counterparts. The repulsive microspheres within these mixtures display heterogeneous dynamics, with some species exhibiting freely diffusive Brownian motion while others are trapped within the gel network during aggregation. PMID:18643205

  8. Benign familial hyperphosphatasemia

    SciTech Connect

    Siraganian, P.A.; Mulvihill, J.J.; Mulivor, R.A.; Miller, R.W. )

    1989-03-03

    Elevated alkaline phosphatase activity in serum suggests bone or liver disease or a neoplasm but can also indicate pregnancy or another benign condition. A family with benign hyperphosphatasemia was studied to elucidate the genetics and enzyme defect. Serum total alkaline phosphatase activity was greater than the population mean in all six family members, and more than 7 SDs above the mean in two of four offspring. Monoclonal antibodies to three alkaline phosphatase isoenzymes, intestinal, placental, and tissue nonspecific demonstrated markedly increased intestinal alkaline phosphatase levels in all family members and significantly elevated liver/bone/kidney activity in the two offspring. Guanidine hydrochloride denaturation of the liver/bone/kidney component showed high alkaline phosphatase activity from liver in both siblings and from bone in one. The mode of inheritance in this family is obscure, but a complex regulation of the products of two different alkaline phosphatase genes seems likely. Steps toward diagnosis are suggested. Early recognition of this benign biochemical abnormality should help to avoid unnecessary diagnostic tests.

  9. Benign Metastasizing Leiomyoma.

    PubMed

    Pacheco-Rodriguez, Gustavo; Taveira-DaSilva, Angelo M; Moss, Joel

    2016-09-01

    Benign metastasizing leiomyoma (BML) is a rare and poorly characterized disease affecting primarily premenopausal women. Asymptomatic patients are often diagnosed incidentally by radiographs or other lung-imaging procedures performed for other indications, and the diagnosis is eventually confirmed by biopsy. Patients with BML are usually treated pharmacologically with antiestrogen therapies or surgically with oophorectomy or hysterectomy. Antiestrogen therapy is typically efficacious and, in general, most patients have a favorable prognosis. Asymptomatic patients with a confirmed diagnosis of BML, may be followed conservatively without treatment. PMID:27514603

  10. Acceleration of Acid-Catalyzed Hydrolysis in a Biphasic System by Sodium Tetracyanocyclopentadienides.

    PubMed

    Sakai, Takeo; Bito, Mariko; Itakura, Makoto; Sato, Honami; Mori, Yuji

    2016-01-01

    The hydrolysis of tert-butyldimethylsilyl L-menthyl ether (3) in a CH2Cl2-1 M HCl biphasic solvent system was accelerated by the addition of sodium tetracyanocyclopentadienides 1. Particularly, the reaction rate was enhanced using sodium salt 1a-c with a lipophilic substituent on the cyclopentadienide ring. From the results obtained by a triphasic experiment, hydrolysis proceeds via the formation of hydronium ion 2 in the aqueous phase by ion exchange, followed by the transfer of 2 to the CH2Cl2 phase. PMID:27373648

  11. Synthesis and characterization of magnesium substituted biphasic mixtures of controlled hydroxyapatite/{beta}-tricalcium phosphate ratios

    SciTech Connect

    Kannan, S.; Lemos, I.A.F.; Rocha, J.H.G.; Ferreira, J.M.F. . E-mail: jmf@cv.ua.pt

    2005-10-15

    The present paper investigates the preparation of magnesium (Mg) substituted biphasic mixtures of different hydroxyapatite (HAP)/{beta}-tricalcium phosphate ({beta}-TCP) ratios through aqueous precipitation method. The concentrations of added magnesium (Mg) were varied with the calcium in order to obtain constant (Ca+Mg)/P ratios of 1.67 ranging from 1.62+0.05, 1.58+0.09 and 1.54+0.13, respectively. The as prepared powders were calcined at different temperatures to study the phase behaviour and thermal stability. The powders were characterized by the following analytical techniques: TG-DTA, X-ray diffraction and FT-IR. The results have shown that substitution of Mg in the calcium-deficient apatites resulted in the formation of biphasic mixtures of different HAP/{beta}-TCP ratios after heating above 700 deg. C. The ratios of the formation of phase mixtures were dependent on the calcium deficiency in the apatites with the higher deficiency having the strongest impact on the increased formation of {beta}-TCP and the substituted Mg was found to stabilize the {beta}-TCP phase. - Graphical abstract: Role of Mg in the behaviour of calcium-deficient apatites during calcination to form biphasic mixtures.

  12. Benign follicular tumors*

    PubMed Central

    Tellechea, Oscar; Cardoso, José Carlos; Reis, José Pedro; Ramos, Leonor; Gameiro, Ana Rita; Coutinho, Inês; Baptista, António Poiares

    2015-01-01

    Benign follicular tumors comprise a large and heterogeneous group of neoplasms that share a common histogenesis and display morphological features resembling one or several portions of the normal hair follicle, or recapitulate part of its embryological development. Most cases present it as clinically nondescript single lesions and essentially of dermatological relevance. Occasionally, however, these lesions be multiple and represent a cutaneous marker of complex syndromes associated with an increased risk of visceral neoplasms. In this article, the authors present the microscopic structure of the normal hair follicle as a basis to understand the type and level of differentiation of the various follicular tumors. The main clinicopathological features and differential diagnosis of benign follicular tumors are then discussed, including dilated pore of Winer, pilar sheath acanthoma, trichoadenoma, trichilemmoma, infundibuloma, proliferating trichilemmal cyst/tumor, trichoblastoma and its variants, pilomatricoma, trichodiscoma/fibrofolliculoma, neurofollicular hamartoma and trichofolliculoma. In addition, the main syndromes presenting with multiple follicular tumors are also discussed, namely Cowden, Birt-Hogg-Dubé, Rombo and Bazex-Dupré-Christol syndromes, as well as multiple tumors of follicular infundibulum (infundibulomatosis) and multiple trichoepitheliomas. Although the diagnosis of follicular tumors relies on histological examination, we highlight the importance of their knowledge for the clinician, especially when in presence of patients with multiple lesions that may be the cutaneous marker of a cancer-prone syndrome. The dermatologist is therefore in a privileged position to recognize these lesions, which is extremely important to provide further propedeutic, appropriate referral and genetic counseling for these patients. PMID:26734858

  13. Ductal carcinoma in situ in a benign phyllodes tumor of breast: A rare presentation.

    PubMed

    Ghosh, Prithwijit; Saha, Kaushik

    2014-07-01

    Phyllodes tumor (PT) is an uncommon tumor of female breast. The tumor clinically, radiologically, cytologically as well as histologically can mimic fibroadenoma which is a common tumor of fibroepithelial group. Ductal carcinoma in situ (DCIS) in the epithelial component of PT is very rare. We report a rare case of intermediate grade DCIS arising in a benign PT in a 42-year-old lady. The patient presented with a small nodule in right breast along with serosanguineous discharge from nipple. Ultrasonography and cytology failed to distinguish between fibroadenoma and PT. Histopathological examination following wide local excision displayed the biphasic tumor comprising of benign looking cellular stroma and epithelial lining. It also demonstrated the foci of intermediate grade DCIS without any invasive component. Considering the clinicoradiological profile along with histopathological features, the diagnosis of DCIS in a benign PT of breast was made. PMID:25097439

  14. Steroid biotransformations in biphasic systems with Yarrowia lipolytica expressing human liver cytochrome P450 genes

    PubMed Central

    2012-01-01

    Background Yarrowia lipolytica efficiently metabolizes and assimilates hydrophobic compounds such as n-alkanes and fatty acids. Efficient substrate uptake is enabled by naturally secreted emulsifiers and a modified cell surface hydrophobicity and protrusions formed by this yeast. We were examining the potential of recombinant Y. lipolytica as a biocatalyst for the oxidation of hardly soluble hydrophobic steroids. Furthermore, two-liquid biphasic culture systems were evaluated to increase substrate availability. While cells, together with water soluble nutrients, are maintained in the aqueous phase, substrates and most of the products are contained in a second water-immiscible organic solvent phase. Results For the first time we have co-expressed the human cytochromes P450 2D6 and 3A4 genes in Y. lipolytica together with human cytochrome P450 reductase (hCPR) or Y. lipolytica cytochrome P450 reductase (YlCPR). These whole-cell biocatalysts were used for the conversion of poorly soluble steroids in biphasic systems. Employing a biphasic system with the organic solvent and Y. lipolytica carbon source ethyl oleate for the whole-cell bioconversion of progesterone, the initial specific hydroxylation rate in a 1.5 L stirred tank bioreactor was further increased 2-fold. Furthermore, the product formation was significantly prolonged as compared to the aqueous system. Co-expression of the human CPR gene led to a 4-10-fold higher specific activity, compared to the co-overexpression of the native Y. lipolytica CPR gene. Multicopy transformants showed a 50-70-fold increase of activity as compared to single copy strains. Conclusions Alkane-assimilating yeast Y. lipolytica, coupled with the described expression strategies, demonstrated its high potential for biotransformations of hydrophobic substrates in two-liquid biphasic systems. Especially organic solvents which can be efficiently taken up and/or metabolized by the cell might enable more efficient bioconversion as compared

  15. Facile synthesis and photocatalytic activity of bi-phase dispersible Cu-ZnO hybrid nanoparticles

    NASA Astrophysics Data System (ADS)

    Liu, Xiao; Liu, HongLing; Zhang, WenXing; Li, XueMei; Fang, Ning; Wang, XianHong; Wu, JunHua

    2015-04-01

    Bi-phase dispersible Cu-ZnO hybrid nanoparticles were synthesized by one-pot non-aqueous nanoemulsion with the use of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO) as the surfactant. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) show high crystallinity of the Cu-ZnO hybrid nanoparticles and an average particle size of ~19.4 nm. The ultraviolet-visible light absorbance spectrometry (UV-vis) and photoluminescence spectrophotometry (PL) demonstrate well dispersibility and excellent optical performance of Cu-ZnO hybrid nanoparticles both in organic and aqueous solvent. The X-ray photoelectron spectroscopy (XPS) confirms Cu1+ and Cu2+ in ZnO. The observation using Sudan red (III) as probe molecule reveals that the Cu-ZnO hybrid nanoparticles possess enhanced photocatalytic activity and stability which are promising for potential applications in photocatalysis.

  16. [Benign endobronchial tumors].

    PubMed

    Nikhtianov, Kh

    1980-01-01

    Endobronchial localizations of benign neoplasms are met with in 24.5 per cent of the cases. Right lung localizations are more frequent. More than half of them are broadly based (57.5 per cent). In most of the cases it is a matter of nonepithelial tumours of which a greater intensity is displayed by hamartomas /7/, vascular /4/ and neurogenic /3/ neoformations. The size of endobronchial tumours varies from 1 to 10 cm. Cases measuring 1-3 cm are the most numerous. Those of the "iceberg" type appear to be larger. The size per se has a relative importance for the clinical picture. Endobronchial tumours exhibit a clear cut clinical picture, and run a clinical course in three stages, determined by the degree of bronchial obturation and longstanding of the condition. The most common symptoms are coughing /80.7 per cent/, expectoration /50.0 per cent/, rales /57.6 per cent/, dullness /38.4 per cent/ and lacking respiration /38.4 per cent/. The nosological entity by itself is less conclusive for the clinical course. The X-ray data have orientation and by no means decisive significance for the diagnosis. The "crab pincers" sign in the bronchial lumen during bronchography has a definite importance. Bronchoscopy in conjunction with biopsy is a dependable method of preoperative diagnosing. It contributes greatly to the nosological diagnosis. Even nowadays, the diagnosis of endobronchial tumours is difficult. A rather exact diagnosis can be made intraoperatively, whereas the most accurate diagnosis is established only after histological study. The treatment of endobronchial benign neoplasms is operative. The number of medium /lobectomies/ and extensive /pulmonectomies/ pulmonary resections is considerable. In case of early diagnosis and intervention, sparing resection is the naturally indicated size of operation - mainly resection and plasty of the bronchi without lobectomy. The advantages of circular resection are substantial. Reconstructive operations of "clarinet" and

  17. Benign prostatic hyperplasia.

    PubMed

    Chughtai, Bilal; Forde, James C; Thomas, Dominique Dana Marie; Laor, Leanna; Hossack, Tania; Woo, Henry H; Te, Alexis E; Kaplan, Steven A

    2016-01-01

    Benign prostatic hyperplasia (BPH), which causes lower urinary tract symptoms (LUTS), is a common diagnosis among the ageing male population with increasing prevalence. Many risks factors, both modifiable and non-modifiable, can increase the risk of development and progression of BPH and LUTS. The symptoms can be obstructive (resulting in urinary hesitancy, weak stream, straining or prolonged voiding) or irritative (resulting in increased urinary frequency and urgency, nocturia, urge incontinence and reduced voiding volumes), or can affect the patient after micturition (for example, postvoid dribble or incomplete emptying). BPH occurs when both stromal and epithelial cells of the prostate in the transitional zone proliferate by processes that are thought to be influenced by inflammation and sex hormones, causing prostate enlargement. Patients with LUTS undergo several key diagnostic investigations before being diagnosed with BPH. Treatment options for men with BPH start at watchful waiting and progress through medical to surgical interventions. For the majority of patients, the starting point on the treatment pathway will be dictated by their symptoms and degree of bother. PMID:27147135

  18. Benign small bowel tumor.

    PubMed Central

    Wilson, J M; Melvin, D B; Gray, G; Thorbjarnarson, B

    1975-01-01

    The clinical record and histologic sections of 84 cases of benign small bowel tumor are reviewed. Manifestations of systemic diseases, congenital anomalies, and lesions of either the ileocecal valve or periampullary region were excluded. In the same time span there were 96 small bowel malignancies. Clinical presentation, pathologic findings, management and result are compared to the collected published experience of about 2000 cases. There were 36 leiomyomas, 22 lipomas, 9 angiomas, 6 neurofibromas and 4 fibromas. Thirty-six men and 48 women were affected; the majority in their fifth and sixth decade. Seventy-eight were operative and 6 autopsy diagnoses. The most common symptom was obstruction (42%) followed by hemorrhage (34%) and pain (22%), relative frequency differing for the various specific tumors. There were rarely significant physical findings. A diagnosis of small bowel tumor was made radiologically in 30 patients. Because of the nonspecificity of other signs and symptoms, an acute awareness of the possibility of small bowel tumor is mandatory for preoperative anticipation of the diagnosis. Local resection was performed in all with no deaths or significant postoperative complications. PMID:1078626

  19. Baritosis: a benign pneumoconiosis.

    PubMed Central

    Doig, A T

    1976-01-01

    Baritosis is one of the benign pneumoconioses in which inhaled particulate matter lies in the lungs for years without producing symptoms, abnormal physical signs, incapacity for work, interference with lung function, or liability to develop pulmonary or bronchial infections or other thoracic disease. Owing to the high radio-opacity of barium, the discrete shadows in the chest radiograph are extremely dense. Even in the most well-marked cases with extreme profusion of the opacities, massive shadows do not occur. When exposure to barium dust ceases the opacities begin slowly to disappear. Nine cases of baritosis occurring in a small factory in which barytes was crushed, graded, and milled are described. Two of the cases occurred after only 18 and 21 month's exposure, and 9 of the 10 men employed for more than one and a half years had baritosis. Five of the affected men examined at intervals since their exposure to barytes ceased in 1964 showed marked clearing of their radiological abnormalities. Images PMID:1257935

  20. Novel Measurements of Aerosol Particle Interfaces Using Biphasic Microfluidics

    NASA Astrophysics Data System (ADS)

    Metcalf, A. R.; Dutcher, C. S.

    2014-12-01

    Secondary organic aerosol (SOA) particles are nearly ubiquitous in the atmosphere and yet there remains large uncertainties in their formation processes and ambient properties. These particles are complex microenvironments, which can contain multiple interfaces due to internal aqueous-organic phase partitioning and to the external liquid-vapor surface. These aerosol interfaces can profoundly affect the fate of condensable organic compounds emitted into the atmosphere by altering the way in which organic vapors interact with the ambient aerosol. Aerosol interfaces affect particle internal structure, species uptake, equilibrium partitioning, activation to cloud condensation or ice nuclei, and optical properties. For example, organic thin films can shield the core of the aerosol from the ambient environment, which may disrupt equilibrium partitioning and mass transfer. To improve our ability to accurately predict the fate of SOA in the atmosphere, we must improve our knowledge of aerosol interfaces and their interactions with the ambient environment. Few technologies exist to accurately probe aerosol interfaces at atmospherically-relevant conditions. In this talk, a novel method using biphasic microscale flows will be introduced for generating, trapping, and perturbing complex interfaces at atmospherically relevant conditions. These microfluidic experiments utilize high-speed imaging to monitor interfacial phenomena at the microscale and are performed with phase contrast and fluorescence microscopy on a temperature-controlled inverted microscope stage. From these experiments, interfacial thermodynamic properties such as surface tension, rheological properties such as interfacial moduli, and kinetic properties such as mass transfer coefficients can be measured or inferred. Chemical compositions of the liquid phases studied here span a range of viscosities and include electrolyte and water soluble organic acid species often observed in the atmosphere, such as mixtures

  1. IMPROVED DECONTAMINATION: INTERFACIAL, TRANSPORT, AND CHEMICAL PROPERTIES OF AQUEOUS SURFACTANT CLEANERS

    EPA Science Inventory

    This investigation is focused on decontamination using environmentally benign aqueous solutions, specifically the removal of organics and associated radionuclide and heavy metal contaminants by synthetic surfactants. Aqueous-based solutions promise several advantages for deconta...

  2. Biphasic Janus particles with nanoscale anisotropy

    NASA Astrophysics Data System (ADS)

    Roh, Kyung-Ho; Martin, David C.; Lahann, Joerg

    2005-10-01

    Advances in the field of nanotechnology have fuelled the vision of future devices spawned from tiny functional components that are able to assemble according to a master blueprint. In this concept, the controlled distribution of matter or `patchiness' is important for creating anisotropic building blocks and introduces an extra design parameter - beyond size and shape. Although the reliable and efficient fabrication of building blocks with controllable material distributions will be of interest for many applications in research and technology, their synthesis has been addressed only in a few specialized cases. Here we show the design and synthesis of polymer-based particles with two distinct phases. The biphasic geometry of these Janus particles is induced by the simultaneous electrohydrodynamic jetting of parallel polymer solutions under the influence of an electrical field. The individual phases can be independently loaded with biomolecules or selectively modified with model ligands, as confirmed by confocal microscopy and transmission electron microscopy. The fact that the spatial distribution of matter can be controlled at such small length scales will provide access to unknown anisotropic materials. This type of nanocolloid may enable the design of multicomponent carriers for drug delivery, molecular imaging or guided self-assembly.

  3. Cholesterol and benign prostate disease.

    PubMed

    Freeman, Michael R; Solomon, Keith R

    2011-01-01

    The origins of benign prostatic diseases, such as benign prostatic hyperplasia (BPH) and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), are poorly understood. Patients suffering from benign prostatic symptoms report a substantially reduced quality of life, and the relationship between benign prostate conditions and prostate cancer is uncertain. Epidemiologic data for BPH and CP/CPPS are limited, however an apparent association between BPH symptoms and cardiovascular disease (CVD) has been consistently reported. The prostate synthesizes and stores large amounts of cholesterol and prostate tissues may be particularly sensitive to perturbations in cholesterol metabolism. Hypercholesterolemia, a major risk factor for CVD, is also a risk factor for BPH. Animal model and clinical trial findings suggest that agents that inhibit cholesterol absorption from the intestine, such as the class of compounds known as polyene macrolides, can reduce prostate gland size and improve lower urinary tract symptoms (LUTS). Observational studies indicate that cholesterol-lowering drugs reduce the risk of aggressive prostate cancer, while prostate cancer cell growth and survival pathways depend in part on cholesterol-sensitive biochemical mechanisms. Here we review the evidence that cholesterol metabolism plays a role in the incidence of benign prostate disease and we highlight possible therapeutic approaches based on this concept. PMID:21862201

  4. Superabsorbent biphasic system based on poly(lactic acid) and poly(acrylic acid)

    NASA Astrophysics Data System (ADS)

    Sartore, Luciana; Pandini, Stefano; Baldi, Francesco; Bignotti, Fabio

    2016-05-01

    In this research work, biocomposites based on crosslinked particles of poly(acrylic acid), commonly used as superabsorbent polymer (SAP), and poly-L-lactic acid (PLLA) were developed to elucidate the role of the filler (i.e., polymeric crosslinked particles) on the overall physico-mechanical behavior and to obtain superabsorbent thermoplastic products. Samples prepared by melt-blending of components in different ratios showed a biphasic system with a regular distribution of particles, with diameter ranging from 5 to 10 μm, within the PLLA polymeric matrix. The polymeric biphasic system, coded PLASA i.e. superabsorbent poly(lactic acid), showed excellent swelling properties, demonstrating that cross-linked particles retain their superabsorbent ability, as in their free counterparts, even if distributed in a thermoplastic polymeric matrix. The thermal characteristics of the biocomposites evidence enhanced thermal stability in comparison with neat PLLA and also mechanical properties are markedly modified by addition of crosslinked particles which induce regular stiffening effect. Furthermore, in aqueous environments the particles swell and are leached from PLLA matrix generating very high porosity. These new open-pore PLLA foams, produced in absence of organic solvents and chemical foaming agents, with good physico-mechanical properties appear very promising for several applications, for instance in tissue engineering for scaffold production.

  5. Environmentally Benign Stab Detonators

    SciTech Connect

    Gash, A E

    2006-07-07

    The coupling of energetic metallic multilayers (a.k.a. flash metal) with energetic sol-gel synthesis and processing is an entirely new approach to forming energetic devices for several DoD and DOE needs. They are also practical and commercially viable manufacturing techniques. Improved occupational safety and health, performance, reliability, reproducibility, and environmentally acceptable processing can be achieved using these methodologies and materials. The development and fielding of this technology will enhance mission readiness and reduce the costs, environmental risks and the necessity of resolving environmental concerns related to maintaining military readiness while simultaneously enhancing safety and health. Without sacrificing current performance, we will formulate new impact initiated device (IID) compositions to replace materials from the current composition that pose significant environmental, health, and safety problems associated with functions such as synthesis, material receipt, storage, handling, processing into the composition, reaction products from testing, and safe disposal. To do this, we will advance the use of nanocomposite preparation via the use of multilayer flash metal and sol-gel technologies and apply it to new small IIDs. This work will also serve to demonstrate that these technologies and resultant materials are relevant and practical to a variety of energetic needs of DoD and DOE. The goal will be to produce an IID whose composition is acceptable by OSHA, EPA, the Clean Air Act, Clean Water Act, Resource Recovery Act, etc. standards, without sacrificing current performance. The development of environmentally benign stab detonators and igniters will result in the removal of hazardous and toxic components associated with their manufacturing, handling, and use. This will lead to improved worker safety during manufacturing as well as reduced exposure of Service personnel during their storage and or use in operations. The

  6. Stoichiometric implications of a biphasic life cycle.

    PubMed

    Tiegs, Scott D; Berven, Keith A; Carmack, Douglas J; Capps, Krista A

    2016-03-01

    Animals mediate flows of elements and energy in ecosystems through processes such as nutrient sequestration in body tissues, and mineralization through excretion. For taxa with biphasic life cycles, the dramatic shifts in anatomy and physiology that occur during ontogeny are expected to be accompanied by changes in body and excreta stoichiometry, but remain little-explored, especially in vertebrates. Here we tested stoichiometric hypotheses related to the bodies and excreta of the wood frog (Lithobates sylvaticus) across life stages and during larval development. Per-capita rates of nitrogen (N) and phosphorus (P) excretion varied widely during larval ontogeny, followed unimodal patterns, and peaked midway through development (Taylor-Kollros stages XV and XII, respectively). Larval mass did not increase steadily during development but peaked at stage XVII and declined until the termination of the experiment at stage XXII. Mass-specific N and P excretion rates of the larvae decreased exponentially during development. When coupled with population-biomass estimates, population-level excretion rates were greatest at stages VIII-X. Percent carbon (C), N, and C:N of body tissue showed weak trends across major life stages; body P and C:P, however, increased sixfold during development from egg to adult. Our results demonstrate that intraspecific ontogenic changes in nutrient contents of excretion and body tissues can be significant, and that N and P are not always excreted proportionally throughout life cycles. These results highlight the dynamic roles that species play in ecosystems, and how the morphological and physiological changes that accompany ontogeny can influence ecosystem-level processes. PMID:26589522

  7. The rare benign liver tumors.

    PubMed

    Skalicky, T; Treska, V; Liska, V; Sutnar, A; Molacek, J; Mirka, H; Ferda, J; Ohlidalova, K

    2007-01-01

    As opposed to malignant secondary tumors, metastases of the colorectal carcinoma are benign tumors of the liver that are quite rare in the Czech Republic. From the 55 patients operated on since 2000 at our department for benign liver tumors, the most frequent are haemangiomas, focal nodular hyperplasia (FNH) and hepatocelular adenoma. Only 7.3% of them form a different histological type of a tumor than this most frequently occurring trio of tumors. The authors describe three cases of rather rare liver tumors with benign behavior that have the potential of becoming malignant. It concerns mucin producing biliary tumors, which correspond to the pancreatic intraductal papillary mucin tumor, hepatic cystadenoma with ovarian stroma and a liver hamartoma in an adult patient (Ref 13). Full Text (Free, PDF) www.bmj.sk. PMID:17694811

  8. Interaction between hydroxypropyl methylcellulose and biphasic calcium phosphate after steam sterilisation: capillary gas chromatography studies.

    PubMed

    Bourges, X; Schmitt, M; Amouriq, Y; Daculsi, G; Legeay, G; Weiss, P

    2001-01-01

    The purpose of this study was to check the chemical stability of an injectable bone substitute (IBS) composed of a 50/50 w/w mixture of 2.92% hydroxypropyl methylcellulose (HPMC) solution in deionized water containing biphasic calcium phosphate (BCP) granules (60% hydroxyapatite/40% beta-tricalcium phosphate w/w). After separation of the organic and mineral phases, capillary gas chromatography (GC) was used to study the possible modification of HPMC due to the contact with BCP granules following steam sterilisation and 32 days storage at room temperature. HPMC was extracted from IBS in aqueous medium, and a dialytic method was then used to extract calcium phosphate salts from the HPMC. The percentage of HPMC extracted from BCP was 98.5%+/-0.5%, as measured by UV. GC showed no chemical modifications after steam sterilisation and storage. PMID:11556737

  9. Interaction between hydroxypropyl methylcellulose and biphasic calcium phosphate after steam sterilisation: capillary gas chromatography studies

    PubMed Central

    Bourges, Xavier; Schmitt, Michel; Amouriq, Yves; Daculsi, Guy; Legeay, Gilbert; Weiss, Pierre

    2001-01-01

    The purpose of this study was to check the chemical stability of an injectable bone substitute (IBS) composed of a 50/50 w/w mixture of a 2.92% hydroxypropyl methylcellulose (HPMC) solution in deionised water containing biphasic calcium phosphate (BCP) granules (60% hydroxyapatite/40% β-tricalcium phosphate w/w). After separation of the organic and mineral phases, capillary gas chromatography (GC) was used to study the possible modification of HPMC due to the contact with BCP granules following steam sterilisation and 32 days of storage at room temperature. HPMC was extracted from IBS in aqueous medium, and a dialytic method was then use to extract calcium phosphate salts from HPMC. The percentage of HPMC extracted from BCP was 98.5% ± 0.5% as measured by a UV method. GC showed no chemical modifications after steam sterilisation and storage. PMID:11556737

  10. Light controlled reversible inversion of nanophosphor-stabilized Pickering emulsions for biphasic enantioselective biocatalysis.

    PubMed

    Chen, Zhaowei; Zhou, Li; Bing, Wei; Zhang, Zhijun; Li, Zhenhua; Ren, Jinsong; Qu, Xiaogang

    2014-05-21

    In this work, by utilizing photochromic spiropyrans conjugated upconversion nanophosphors, we have successfully prepared NIR/visible light tuned interfacially active nanoparticles for the formulation of Pickering emulsions with reversible inversion properties. By loading a model enantioselective biocatalytic active bacteria Alcaligenes faecalis ATCC 8750 in the aqueous phase, we demonstrated for the first time that the multifunctional Pickering emulsion not only highly enhanced its catalytic performance but also relieved the substrate inhibition effect. In addition, product recovery, and biocatalysts and colloid emulsifiers recycling could be easily realized based on the inversion ability of the Pickering emulsion. Most importantly, the utilization of NIR/visible light to perform the reversible inversion without any chemical auxiliaries or temperature variation showed little damage toward the biocatalysts, which was highlighted by the high catalytic efficiency and high enantioselectivity even after 10 cycles. The NIR/visible light controlled Pickering emulsion showed promising potential as a powerful technique for biocatalysis in biphasic systems. PMID:24784766

  11. Perfluorinated quaternary ammonium salts of polyoxometalate anions: Fluorous biphasic oxidation catalysis with and without fluorous solvents

    SciTech Connect

    Maayan, Galia; Fish, Richard H.; Neumann, Ronny

    2003-05-28

    Perfluorinated quaternary ammonium cations, [CF{sub 3}(CF{sub 2}){sub 7}(CH{sub 2}){sub 3}]{sub 3}CH{sub 3}N{sup +} (RFN{sup +}), were synthesized and used as counter cations for the [WZnM{sub 2}(H{sub 2}O){sub 2}(ZnW{sub 9}O{sub 34}){sub 2}]{sup 12-} (M = Mn(II), Zn(II)), polyoxometalate. The (RFN{sup +}){sub 12}[WZnM{sub 2}(H{sub 2}O){sub 2}(ZnW9O{sub 34}){sub 2}] compounds were fluorous biphasic catalysts for alcohol and alkenol oxidation, and alkene epoxidation with aqueous hydrogen peroxide. Reaction protocols with or without a fluorous solvent were tested. The catalytic activity and selectivity was affected both by the hydrophobicity of the solvent and the substrate.

  12. In situ synthesis of magnesium-substituted biphasic calcium phosphate and in vitro biodegradation

    SciTech Connect

    Kim, Tae-Wan; Lee, Hyeong-Shin; Kim, Dong-Hyun; Jin, Hyeong-Ho; Hwang, Kyu-Hong; Lee, Jong Kook; Park, Hong-Chae; Yoon, Seog-Young

    2012-09-15

    Highlights: ► Mg–BCP were successfully prepared through in situ aqueous co-precipitation method. ► The amount of β-TCP phase was changed with the magnesium substitution level. ► The substitution of magnesium led to a decrease in the unit cell volume. ► Mg–BCP could be able to develop a new apatite phase on the surface faster than BCP. -- Abstract: In situ preparation of magnesium (Mg) substituted biphasic calcium phosphate (BCP) of hydroxyapatite (HAp)/β-tricalcium phosphate (β-TCP) were carried out through aqueous co-precipitation method. The concentrations of added magnesium were varied with the calcium in order to obtain constant (Ca + Mg)/P ratios of 1.602. X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) spectroscopy were used to characterize the structure of synthesized magnesium substituted BCP powders. The results have shown that substitution of magnesium in the calcium deficient apatites revealed the formation of biphasic mixtures of different HAp/β-TCP ratios after heating at 1000 °C. The ratios of the formation of phase mixtures were dependent on the content of magnesium. After immersing in Hanks’ balanced salt solution (HBSS) for 1 week, 1 wt% magnesium substituted BCP powders were degraded and precipitation started to be formed with small granules consisting of number of flake-like crystal onto the surface of synthesized powders. On the other hand, in the case of pure BCP powders, the formation of new precipitates was detected after immersion in HBSS for 2 weeks. On the basis of these results, magnesium substituted BCP could be able to develop a new apatite phase on the surface in contact with physiological fluids faster than BCP does. In addition, the retention time to produce the new apatite phase in implantation operation for the BCP powder could be controlled by the amount of magnesium substitution.

  13. Diagnosing Common Benign Skin Tumors.

    PubMed

    Higgins, James C; Maher, Michael H; Douglas, Mark S

    2015-10-01

    Patients will experience a wide range of skin growths and changes over their lifetime. Family physicians should be able to distinguish potentially malignant from benign skin tumors. Most lesions can be diagnosed on the basis of history and clinical examination. Lesions that are suspicious for malignancy, those with changing characteristics, symptomatic lesions, and those that cause cosmetic problems may warrant medical therapy, a simple office procedure (e.g., excision, cryosurgery, laser ablation), or referral. Acrochordons are extremely common, small, and typically pedunculated benign neoplasms. Simple scissor or shave excision, electrodesiccation, or cryosurgery can be used for treatment. Sebaceous hyperplasia presents as asymptomatic, discrete, soft, pale yellow, shiny bumps on the forehead or cheeks, or near hair follicles. Except for cosmesis, they have no clinical significance. Lipomas are soft, flesh-colored nodules that are easily moveable under the overlying skin. Keratoacanthomas are rapidly growing, squamoproliferative benign tumors that resemble squamous cell carcinomas. Early simple excision is recommended. Pyogenic granuloma is a rapidly growing nodule that bleeds easily. Treatment includes laser ablation or shave excision with electrodesiccation of the base. Dermatofibromas are an idiopathic benign proliferation of fibroblasts. No treatment is required unless there is a change in size or color, bleeding, or irritation from trauma. Epidermal inclusion cysts can be treated by simple excision with removal of the cyst and cyst wall. Seborrheic keratoses and cherry angiomas generally do not require treatment. PMID:26447443

  14. Pathogenesis of benign adrenocortical tumors.

    PubMed

    Vezzosi, Delphine; Bertherat, Jérôme; Groussin, Lionel

    2010-12-01

    Most adrenocortical tumors (ACT) are benign unilateral adrenocortical adenomas, often discovered incidentally. Exceptionally, ACT are bilateral. However bilateral ACT have been very helpful to progress in the pathophysiology of ACT. Although most ACT are of sporadic origin, they may also be part of syndromic and/or hereditary disorders. The identification of the genetics of familial diseases associated with benign ACT has been helpful to define somatic alterations in sporadic ACT: for example, identification of PRKAR1A mutations in Carney complex or alterations of the Wnt/β-catenin pathway in Familial Adenomatous Polyposis Coli. Components of the cAMP signaling pathway-for example, adrenocorticotropic-hormone receptors and other membrane receptors, Gs protein, phosphodiesterases and protein kinase A-can be altered to various degrees in benign cortisol-secreting ACT. These progress have been important for the understanding of the pathogenesis of benign ACT, but already have profound implications for clinical management, for example in unraveling the genetic origin of disease in some patients with ACT. They also have therapeutic consequences, and should help to develop new therapeutic options. PMID:21115158

  15. Biphasic nanoparticles made by electrified jetting

    NASA Astrophysics Data System (ADS)

    Lahann, Joerg

    2005-03-01

    Nano-colloids have recently attracted intense attention due to unique properties that are distinctly different from bulk solid-state materials; including unique magnetic, electronic, optical, chemical, and biological characteristics. The vision that these nano-objects could essentially act as functional components in novel device generations, which ``magically'' assemble following a master blueprint void any human manipulation, has resulted in a new ``gold rush'' in materials science. These concepts have results in the synthesis of a multitude of nano-objects, such as nano-wires, nano-rods, nano-disks, or nano-prisms.^ Recently, nano-particles with anisotropic materials distributions (biphasic nano-particles) moved in the focus of research. Our approach differs fundamentally from the above-mentioned methods in that it takes advantage of electrified polymer jets to create anisotropic materials distributions in nano-objects. jetting is a process to generate liquid jets by use of electrostatic forces. It is well-known that high electrical potentials (typically several thousand volts) applied between the jetting liquids that are fed through a capillary and a collecting substrate will induce jetting of a charged liquid. The differences in the final morphologies from similar processes are mainly determined by the properties of the jetting liquids and the process parameters. transmission electron microscopy, scanning electron microscopy, and scanning laser confocal microscopy, we demonstrate the applicability of the process to control size, shape, and materials distribution at the nanoscale. The resulting anisotropic nanoparticles may have potential applications for targeted drug delivery or as electro-rehological fluids. a) F. M. Van der Kooij, K. Kassapidou and H. N. W. Lekkerkerker, Liquid crystal phase transitions in suspensions of polydisperse plate-like particles, Nature 406, 868 (2000); b) C. A. Mirkin, R. L. Letsinger, R. C. Mucic and J. J. Storhoff, A DNA

  16. Progress on the biphase turbine at Cerro Prieto

    SciTech Connect

    Cerini, D.; Hays, L.; Studhalter, W.

    1997-12-31

    The status of a Biphase turbine power plant being installed at the Cerro Prieto geothermal field is presented. The major modules for the power plant are completed except for a back pressure steam turbine. The power plant will be started in April 1997 with the Biphase turbine alone followed by the addition of the steam turbine module two months later. The current power plant performance level is 2780 kWe due to a decline in the well. An increase in power output to 4060 kWe by adding the flow from another well is planned. The addition of five Biphase power plants with a total power output of 21.2 megawatts is described.

  17. Case Report: Multifocal biphasic squamoid alveolar renal cell carcinoma

    PubMed Central

    Lopez, Jose Ignacio

    2016-01-01

    A multifocal biphasic squamoid alveolar renal cell carcinoma in a 68-year-old man is reported. Four different peripheral tumor nodules were identified on gross examination. A fifth central tumor corresponded to a conventional clear cell renal cell carcinoma. Biphasic squamoid alveolar renal cell carcinoma is a rare tumor that has been very recently characterized as a distinct histotype within the spectrum of papillary renal cell carcinoma. Immunostaining with cyclin D1 seems to be specific of this tumor subtype. This is the first reported case with multifocal presentation. PMID:27158455

  18. Evolution of a mini-scale biphasic dissolution model: Impact of model parameters on partitioning of dissolved API and modelling of in vivo-relevant kinetics.

    PubMed

    Locher, Kathrin; Borghardt, Jens M; Frank, Kerstin J; Kloft, Charlotte; Wagner, Karl G

    2016-08-01

    Biphasic dissolution models are proposed to have good predictive power for the in vivo absorption. The aim of this study was to improve our previously introduced mini-scale dissolution model to mimic in vivo situations more realistically and to increase the robustness of the experimental model. Six dissolved APIs (BCS II) were tested applying the improved mini-scale biphasic dissolution model (miBIdi-pH-II). The influence of experimental model parameters including various excipients, API concentrations, dual paddle and its rotation speed was investigated. The kinetics in the biphasic model was described applying a one- and four-compartment pharmacokinetic (PK) model. The improved biphasic dissolution model was robust related to differing APIs and excipient concentrations. The dual paddle guaranteed homogenous mixing in both phases; the optimal rotation speed was 25 and 75rpm for the aqueous and the octanol phase, respectively. A one-compartment PK model adequately characterised the data of fully dissolved APIs. A four-compartment PK model best quantified dissolution, precipitation, and partitioning also of undissolved amounts due to realistic pH profiles. The improved dissolution model is a powerful tool for investigating the interplay between dissolution, precipitation and partitioning of various poorly soluble APIs (BCS II). In vivo-relevant PK parameters could be estimated applying respective PK models. PMID:27297570

  19. A rare benign ovarian tumour.

    PubMed

    Palmeiro, Marta Morna; Cunha, Teresa Margarida; Loureiro, Ana Luisa; Esteves, Gonçalo

    2016-01-01

    Sclerosing stromal tumour (SST) of the ovary is an extremely rare and benign ovarian neoplasm, accounting for 6% of the sex cord stromal ovarian tumours subtype. Usually, it is found during the second and third decades of life. Patients commonly present with pelvic pain, a palpable pelvic mass or menstrual irregularity. We report a case of a 20-year-old woman reporting of mild pelvic pain, with normal laboratory data. On imaging examinations, a large right adnexal tumour was found, with features suggesting an ovarian sex cord tumour. The patient underwent right salpingo-oophorectomy, diagnosing a SST of the ovary. This paper also reviews the literature, and emphasises the typical pathological and imaging characteristics of these rare benign ovarian lesions, and their impact, in a conservative surgery. PMID:26933186

  20. Benign Pediatric Salivary Gland Lesions.

    PubMed

    Carlson, Eric R; Ord, Robert A

    2016-02-01

    Salivary gland lesions are rare in pediatric patients. In addition, the types of salivary gland tumors are different in their distribution in specific sites in the major and minor salivary glands in children compared with adults. This article reviews benign neoplastic and nonneoplastic salivary gland disorders in pediatric patients to help clinicians to develop an orderly differential diagnosis that will lead to expedient treatment of pediatric patients with salivary gland lesions. PMID:26614702

  1. Process boundaries of irreversible scCO2 -assisted phase separation in biphasic whole-cell biocatalysis.

    PubMed

    Brandenbusch, Christoph; Glonke, Sebastian; Collins, Jonathan; Hoffrogge, Raimund; Grunwald, Klaudia; Bühler, Bruno; Schmid, Andreas; Sadowski, Gabriele

    2015-11-01

    The formation of stable emulsions in biphasic biotransformations catalyzed by microbial cells turned out to be a major hurdle for industrial implementation. Recently, a cost-effective and efficient downstream processing approach, using supercritical carbon dioxide (scCO2 ) for both irreversible emulsion destabilization (enabling complete phase separation within minutes of emulsion treatment) and product purification via extraction has been proposed by Brandenbusch et al. (2010). One of the key factors for a further development and scale-up of the approach is the understanding of the mechanism underlying scCO2 -assisted phase separation. A systematic approach was applied within this work to investigate the various factors influencing phase separation during scCO2 treatment (that is pressure, exposure of the cells to CO2 , and changes of cell surface properties). It was shown that cell toxification and cell disrupture are not responsible for emulsion destabilization. Proteins from the aqueous phase partially adsorb to cells present at the aqueous-organic interface, causing hydrophobic cell surface characteristics, and thus contribute to emulsion stabilization. By investigating the change in cell-surface hydrophobicity of these cells during CO2 treatment, it was found that a combination of catastrophic phase inversion and desorption of proteins from the cell surface is responsible for irreversible scCO2 mediated phase separation. These findings are essential for the definition of process windows for scCO2 -assisted phase separation in biphasic whole-cell biocatalysis. PMID:26012371

  2. Bi-phase transition diagrams of metallic thin multilayers

    SciTech Connect

    Li, J.C.; Liu, W.; Jiang, Q. . E-mail: jiangq@jlu.edu.cn

    2005-02-01

    Phase transitions of metallic multilayers induced by differences in interface energy are considered thermodynamically, based on a thermodynamic model for interface energy and the Goldschmidt premise for lattice contraction. Bi-phase transition diagrams of Co/Cr, Zr/Nb, Ti/Nb and Ti/Al multilayers are constructed, which are in agreement with experimental results.

  3. Intrinsically Stretchable Biphasic (Solid-Liquid) Thin Metal Films.

    PubMed

    Hirsch, Arthur; Michaud, Hadrien O; Gerratt, Aaron P; de Mulatier, Séverine; Lacour, Stéphanie P

    2016-06-01

    Stretchable biphasic conductors are formed by physical vapor deposition of gallium onto an alloying metal film. The properties of the photolithography-compatible thin metal films are highlighted by low sheet resistance (0.5 Ω sq(-1) ) and large stretchability (400%). This novel approach to deposit and pattern liquid metals enables extremely robust, multilayer and soft circuits, sensors, and actuators. PMID:26923313

  4. Process for separating and recovering an anionic dye from an aqueous solution

    DOEpatents

    Rogers, Robin; Horwitz, E. Philip; Bond, Andrew H.

    1998-01-01

    A solid/liquid phase process for the separation and recovery of an anionic dye from an aqueous solution is disclosed. The solid phase comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the anionic dye molecules are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt. After contact between the aqueous solution and separation particles, the anionic dye is bound to the particles. The bound anionic dye molecules are freed from the separation particles by contacting the anionic dye-bound particles with an aqueous solution that does not contain a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt to form an aqueous anionic dye solution whose anionic dye concentration is preferably higher than that of the initial dye-containing solution.

  5. Process for separating and recovering an anionic dye from an aqueous solution

    DOEpatents

    Rogers, R.; Horwitz, E.P.; Bond, A.H.

    1998-01-13

    A solid/liquid phase process for the separation and recovery of an anionic dye from an aqueous solution is disclosed. The solid phase comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the anionic dye molecules are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt. After contact between the aqueous solution and separation particles, the anionic dye is bound to the particles. The bound anionic dye molecules are freed from the separation particles by contacting the anionic dye-bound particles with an aqueous solution that does not contain a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt to form an aqueous anionic dye solution whose anionic dye concentration is preferably higher than that of the initial dye-containing solution. 7 figs.

  6. Biphasic survival analysis of trypanotolerance QTL in mice.

    PubMed

    Koudandé, O D; Thomson, P C; Bovenhuis, H; Iraqi, F; Gibson, J P; van Arendonk, J A M

    2008-04-01

    A marker-assisted introgression (MAI) experiment was conducted to transfer trypanotolerance quantitative trait loci (QTL) from a donor mouse strain, C57BL/6, into a recipient mouse strain, A/J. The objective was to assess the effect of three previously identified chromosomal regions on mouse chromosomes 1 (MMU1), 5 (MMU5) and 17 (MMU17) in different genetic backgrounds on the survival pattern following infection with Trypanosoma congolense. An exploratory data analysis revealed a biphasic pattern of time to death, with highly distinct early and late mortality phases. In this paper, we present survival analysis methods that account for the biphasic mortality pattern and results of reanalyzing the data from the MAI experiment. The analysis with a Weibull mixture model confirmed the biphasic pattern of time to death. Mortality phase, an unobserved variable, appears to be an important factor influencing survival time and is modeled as a binary outcome variable using logistic regression analysis. Accounting for this biphasic pattern in the analysis reveals that a previously observed sex effect on average survival is rather an effect on proportion of mice in the two mortality phases. The C57BL/6 (donor) QTL alleles on MMU1 and MMU17 act dominantly in the late mortality phase while the A/J (recipient) QTL allele on MMU17 acts dominantly in the early mortality phase. From this study, we found clear evidence for a biphasic survival pattern and provided models for its analysis. These models can also be used when studying defense mechanisms against other pathogens. Finally, these approaches provide further information on the nature of gene actions. PMID:18253157

  7. Glucose dehydration to 5-hydroxymethylfurfural in a biphasic system over solid acid foams.

    PubMed

    Ordomsky, Vitaly V; van der Schaaf, John; Schouten, Jaap C; Nijhuis, T Alexander

    2013-09-01

    A solid acid foam-structured catalyst based on a binderless zirconium phosphate (ZrPO) coating on aluminum foam was prepared. The catalyst layer was obtained by performing a multiple washcoating procedure of ZrPO slurry on the anodized aluminum foam. The effect of the pretreatment of ZrPO, the concentration of the slurry, and the amount of coating on the properties of the foam was studied. The catalytic properties of the prepared foams have been evaluated in the dehydration of glucose to 5-hydroxymethylfurfural (HMF) in a biphasic reactor. The catalytic behavior of ZrPO foam-based catalysts was studied in a rotating foam reactor and compared with that of bulk ZrPO. The effect of a silylation procedure on the selectivity of the process was shown over bulk and foam catalysts. This treatment resulted in a higher selectivity due to the deactivation of unselective Lewis acid sites. Addition of methylisobutylketone leads to extraction of HMF from the aqueous phase and stabilization of the selectivity to HMF over bulk ZrPO. A more intensive contact of the foam with the aqueous and organic phases leads to an increase in the selectivity and resistance to deactivation of the foam in comparison with a bulk catalyst. PMID:23616489

  8. A feasible process for furfural production from the pre-hydrolysis liquor of corncob via biochar catalysts in a new biphasic system.

    PubMed

    Deng, Aojie; Lin, Qixuan; Yan, Yuhuan; Li, Huiling; Ren, Junli; Liu, Chuanfu; Sun, Runcang

    2016-09-01

    A feasible approach was developed to produce furfural from the pre-hydrolysis liquor of corncob via biochar catalysts as the solid acid catalyst in a new biphasic system with dichloromethane (DCM) as the organic phase and the concentrated pre-hydrolysis liquor (CPHL) containing NaCl as the aqueous phase. The biochar catalyst possessing many acidity groups (SO3H, COOH and phenolic OH groups) was prepared by the carbonization and sulfonation process of the corncob hydrolyzed residue. The influence of the catalytic condition on furfural yield and selectivity was comparatively studied. It was found that 81.14% furfural yield and 83.0% furfural selectivity were obtained from CPHL containing 5wt% xylose using this biochar catalyst in the CPHL-NaCl/DCM biphasic system at 170°C for 60min. In addition, with the regeneration process, this catalyst displayed the high performance and excellent recyclability. PMID:27295253

  9. Biphasic Response of Ciprofloxacin in Human Fibroblast Cell Cultures

    PubMed Central

    Hincal, Filiz; Gürbay, Aylin; Favier, Alain

    2003-01-01

    To investigate the possibility of the involvement of an oxidative stress induction in the mechanism of the cytotoxic effect of quinolone antibiotics, we examined the viability of human fibroblast cells exposed to ciprofloxacin (CPFX), and measured the levels of lipid peroxidation (LP), glutathione (GSH), and the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX). The data showed that the effect of CPFX on the viability of cells, as determined by neutral red uptake assay, was time-dependent, and the dose-response relation was biphasic. Cytotoxicity was not observed in the concentration range 5–150 mg/l CPFX when the cells were incubated for 24 h. In contrast, lower concentrations (5 and 12.5 mg/l) of CPFX increased the cell growth in all incubation periods tested. Marked decreases in the viability of fibroblasts were observed at concentrations 50 and 75 mg/l, and ≥50 mg/l, following 48 and 72 h exposure, respectively (p < 0.05). However, when the cells were exposed to > 75 mg/l CPFX for 48 h, no cytotoxicity was observed. By exposing fibroblast cultures to 75 mg/l CPFX for 48 h, an induction of LP enhancement and a marked decrease in intracellular GSH were observed. Vitamin E pretreatment of the cells lowered the level of LP, increased the total GSH content, and provided significant protection against CPFX-induced cytotoxicity. The biphasic effect of CPFX possibly resulted from the complex dose-dependent relationships between reactive oxygen species (ROS), cell proliferation, and cell viability. It was previously reported, in fact, for several cell models that ROS exert a biphasic effect on cell growth. Furthermore, cultured fibroblasts release their own free radicals, and the inhibition of endogenous ROS inhibits the fibroblast cell proliferation, whereas the effect of exogenous ROS is biphasic. PMID:19330132

  10. Improved internal defibrillation efficacy with a biphasic waveform.

    PubMed

    Fain, E S; Sweeney, M B; Franz, M R

    1989-02-01

    Clinically available automatic implantable defibrillators use a monophasic truncated exponential waveform shock; after delivery the charge remaining on the device's capacitors is "dumped" internally and wasted. The efficacy of a monophasic and biphasic truncated exponential defibrillation waveform produced by a single capacitor discharge was compared in seven closed-chest, pentobarbital-anesthetized dogs. Defibrillation leads consisted of a new deployable intrapericardial electrode system. The monophasic waveform was positive and 6 msec in duration. The biphasic waveform had a positive phase identical to that of the monophasic waveform and a negative phase of equal duration with its initial voltage equal to 50% of the final voltage of the positive phase. Defibrillation shocks of varying initial voltage were delivered to construct curves of the percentage of successful defibrillation versus initial voltage and delivered energy, and the voltage and energy required for 50% (V50 and E50, respectively) and 80% (V80 and E80, respectively) success were compared. The biphasic waveform had significantly lower initial voltage (V50: 194 +/- 48 volts vs 227 +/- 48 volts, p less than 0.001; V80: 217 +/- 55 volts vs 256 +/- 66 volts, p less than 0.02) and energy (E50: 2.7 +/- 1.3 joules vs 3.4 +/- 1.5 joules, p less than 0.01; E80: 3.4 +/- 1.6 joules vs 4.3 +/- 2.2 joules, p less than 0.05) requirements than the monophasic waveform. It is concluded that a biphasic waveform produced by a single discharge that uses the "free" energy remaining on the capacitors significantly reduces the initial voltage and energy requirements for successful defibrillation and may improve the efficacy of future automatic implantable defibrillators. PMID:2916410

  11. Biphasic Dose Response in Low Level Light Therapy

    PubMed Central

    Huang, Ying-Ying; Chen, Aaron C.-H.; Carroll, James D.; Hamblin, Michael R.

    2009-01-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response. PMID:20011653

  12. The Impact of Compact Layer in Biphasic Scaffold on Osteochondral Tissue Engineering

    PubMed Central

    Cheng, Jian-Hua; Zhou, Wei; Xiong, Zhuo; Mu, Yun-Jing; Liu, Jian

    2013-01-01

    The structure of an osteochondral biphasic scaffold is required to mimic native tissue, which owns a calcified layer associated with mechanical and separation function. The two phases of biphasic scaffold should possess efficient integration to provide chondrocytes and osteocytes with an independent living environment. In this study, a novel biphasic scaffold composed of a bony phase, chondral phase and compact layer was developed. The compact layer-free biphasic scaffold taken as control group was also fabricated. The purpose of current study was to evaluate the impact of the compact layer in the biphasic scaffold. Bony and chondral phases were seeded with autogeneic osteoblast- or chondrocyte-induced bone marrow stromal cells (BMSCs), respectively. The biphasic scaffolds-cells constructs were then implanted into osteochondral defects of rabbits’ knees, and the regenerated osteochondral tissue was evaluated at 3 and 6 months after surgery. Anti-tensile and anti-shear properties of the compact layer-containing biphasic scaffold were significantly higher than those of the compact layer-free biphasic scaffold in vitro. Furthermore, in vivo studies revealed superior macroscopic scores, glycosaminoglycan (GAG) and collagen content, micro tomograph imaging results, and histological properties of regenerated tissue in the compact layer-containing biphasic scaffold compared to the control group. These results indicated that the compact layer could significantly enhance the biomechanical properties of biphasic scaffold in vitro and regeneration of osteochondral tissue in vivo, and thus represented a promising approach to osteochondral tissue engineering. PMID:23382984

  13. Management of Benign Prostatic Hyperplasia.

    PubMed

    Kim, Eric H; Larson, Jeffrey A; Andriole, Gerald L

    2016-01-01

    Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms (LUTS) commonly affect older men. Age-related changes associated with metabolic disturbances, changes in hormone balance, and chronic inflammation may cause BPH development. The diagnosis of BPH hinges on a thorough medical history and focused physical examination, with attention to other conditions that may be causing LUTS. Digital rectal examination and urinalysis should be performed. Other testing may be considered depending on presentation of symptoms, including prostate-specific antigen, serum creatinine, urine cytology, imaging, cystourethroscopy, post-void residual, and pressure-flow studies. Many medical and surgical treatment options exist. Surgery should be reserved for patients who either have failed medical management or have complications from BPH, such as recurrent urinary tract infections, refractory urinary retention, bladder stones, or renal insufficiency as a result of obstructive uropathy. PMID:26331999

  14. [Radiotherapy of benign intracranial tumors].

    PubMed

    Delannes, M; Latorzeff, I; Chand, M E; Huchet, A; Dupin, C; Colin, P

    2016-09-01

    Most of the benign intracranial tumors are meningiomas, vestibular schwannomas, pituitary adenomas, craniopharyngiomas, and glomus tumors. Some of them grow very slowly, and can be observed without specific treatment, especially if they are asymptomatic. Symptomatic or growing tumors are treated by surgery, which is the reference treatment. When surgery is not possible, due to the location of the lesion, or general conditions, radiotherapy can be applied, as it is if there is a postoperative growing residual tumor, or a local relapse. Indications have to be discussed in polydisciplinary meetings, with precise evaluation of the benefit and risks of the treatments. The techniques to be used are the most modern ones, as multimodal imaging and image-guided radiation therapy. Stereotactic treatments, using fractionated or single doses depending on the size or the location of the tumors, are commonly realized, to avoid as much a possible the occurrence of late side effects. PMID:27523417

  15. Preferential occupancy of strontium in the hydroxyapatite lattice in biphasic mixtures formed from non-stoichiometric calcium apatites.

    PubMed

    Nandha Kumar, P; Mishra, Sandeep K; Udhay Kiran, R; Kannan, S

    2015-05-01

    The present study reports the variations in phase content of biphasic mixtures and structural changes induced by different levels of strontium addition in calcium-deficient apatite (Ca/P = 1.60) powders during heat treatment. The synthesis was attempted by an in situ aqueous precipitation technique and X-ray diffraction, Raman spectroscopy and Rietveld refinement of the powder X-ray diffraction data were employed for comprehensive analysis. The results confirm the preferential occupancy of Sr(2+) at two different Ca(2+) sites of the hydroxyapatite [Ca10(PO4)6(OH)2, HAP] lattice, with the Ca(2+) (2) site accommodating more Sr(2+) than the Ca(2+) (1) site. Increasing Sr(2+) addition in calcium-deficient apatite has led to a decline in the phase content of β-tricalcium phosphate [β-Ca3(PO4)2, β-TCP] in biphasic mixtures of HAP and β-TCP. Sr(2+) addition exceeding the critical limit of a (Ca + Sr)/P > 1.75 molar ratio has resulted in the formation of CaO as an additional phase, and this justifies the lack of enough PO4(3-) ions to promote any kind of calcium phosphate precipitation. Sr(2+) accommodation in the lattice sites of HAP has induced an increase in the lattice parameters and has also led to the significant distortion of the PO4 tetrahedron and OH groups, confirmed by Raman and FT-IR spectroscopic techniques. PMID:25851342

  16. Benign Phyllodes Tumor of the Vulva: A Case Report and Literature Review

    PubMed Central

    Denlinger, LeAnn N.; Lokhandwala, Parvez M.

    2015-01-01

    Phyllodes tumor is an uncommon breast lesion with characteristic histologic appearance when examined by hematoxylin and eosin staining: leaf-like fronds projecting into cystic spaces on low-power microscopy, and biphasic (epithelial and stromal) components on high-power microscopy. We report a rare primary case of this tumor arising within the vulva. A 34-year old African American female presented with a 3 cm slow-growing vulvar mass initially thought to be an inclusion cyst. The lesion was excised and histologic examination demonstrated this lesion to be a rare case of benign phyllodes tumor with morphologic features similar to those arising from breast tissue. Patient received no further treatment and did not exhibit any recurrence or metastasis. Nearly two years after excision, the patient died due to an unrelated medical cause. This rare tumor should be considered in the differential diagnosis for women presenting with a slow-growing vulvar mass. PMID:26788277

  17. Benign Phyllodes Tumor of the Vulva: A Case Report and Literature Review.

    PubMed

    Denlinger, LeAnn N; Lokhandwala, Parvez M; Abendroth, Catherine S

    2015-12-29

    Phyllodes tumor is an uncommon breast lesion with characteristic histologic appearance when examined by hematoxylin and eosin staining: leaf-like fronds projecting into cystic spaces on low-power microscopy, and biphasic (epithelial and stromal) components on high-power microscopy. We report a rare primary case of this tumor arising within the vulva. A 34-year old African American female presented with a 3 cm slow-growing vulvar mass initially thought to be an inclusion cyst. The lesion was excised and histologic examination demonstrated this lesion to be a rare case of benign phyllodes tumor with morphologic features similar to those arising from breast tissue. Patient received no further treatment and did not exhibit any recurrence or metastasis. Nearly two years after excision, the patient died due to an unrelated medical cause. This rare tumor should be considered in the differential diagnosis for women presenting with a slow-growing vulvar mass. PMID:26788277

  18. [Benign phylloides tumor of the breast. Considerations on a clinical case].

    PubMed

    Biondi, Antonio; Di Giuntao, Michela; Motta, Salvatore; Privitera, Giuseppe; Fichera, Debora Simona; Ciuni, Roberto; Basile, Francesco

    2009-01-01

    Phyllodes tumors are unusual biphasic fibroepithelial neoplasms of the breast, accounting for < 1% of all breast tumors and raising issues of diagnosis and therapeutic choice. They can grow quickly and when the maximum diameter is greater than 10 cm. We talk about giant phyllodes tumors. Ultrasound, Mammography and FNA are not effective. A potentially useful diagnostic modality is MRI. Core tissue biopsy or incisional biopsy represent the preferred means of pre-operative diagnosis. Conservative treatment can be effective also in giant tumors depending upon the size of the tumor and the breast if a complete excision with an adequate margin of normal breast tissue can be achieved, so avoiding local recurrence often accompanied by worse histopathology. The Authors report the case of a giant benign phyllode tumor of the breast treated with conservative surgery, quadrantectomy and oncoplasty. No local recurrence at 4 years follow-up. PMID:20476682

  19. SOME NOVEL LIQUID PARTITIONING SYSTEMS: WATER-IONIC LIQUIDS AND AQUEOUS BIPHASIC SYSTEMS. (R828257)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  20. Influence of saline solution on hydration behavior of β-dicalcium silicate in comparison with biphasic calcium phosphate/hydroxyapatite bio-ceramics.

    PubMed

    Radwan, M M; Abd El-Hamid, H K; Mohamed, A F

    2015-12-01

    The influence of using saline solution as mixing and curing liquid on some characteristics of β-dicalcium silicate (β-C2S) and biphasic compound tri-calcium phosphate/hydroxyapatite (TCP/HAp) bio-ceramics was investigated. β-C2S (27-30 nm) was prepared by solid state reaction at 1450°C, while biphasic compound TCP/HAp (7-15 nm) was synthesized from an aqueous solution of Ca(NO3)2·4H2O and (NH4)2HPO4·12H2O by chemical precipitation method. Setting times, compressive strength, pH values, X-ray diffraction analysis, infrared spectroscopy, scanning electron microscopy (SEM) were investigated. The evaluation of cytotoxicity of both calcium silicate and biphasic compounds to human gingival fibroblasts was carried out. The use of saline solution as mixing and immersing liquid shortened the setting time for the two bio-cements. TCP/HAp did not show any mechanical strength but β-C2S showed good strength values. Both synthesized compounds showed a moderate cytotoxicity and both materials were effective in a no significant way. PMID:26354276

  1. Biphasic dissolution method for quality control and assurance of drugs containing active substances in the form of weak acid salts.

    PubMed

    Franc, Aleš; Muselłk, Jan; Goněc, Roman; Vetchý, David

    2016-03-01

    Substances in the form of weak acid salts have been found to be problematic for dissolution testing. Their absorption can start only after they are turned into the form of an acid following the gastric passage although they were administered in the form of a salt. Due to poor solubility, they cannot be tested in acidic gastric environment for a biased dissolution profile. The biphasic dissolution method is promising for overcoming this obstacle. Tablets with warfarin clathrate sodium salt in two concentrations and two different particle size distributions were tested as a suitable model for finding the medium and process conditions of dissolution. The dissolution method based on the use of the upper organic layer (1-octanol) and the lower aqueous layer 0.1 mol L(-1) HCl) was found suitable and discriminatory for tablets containing active substances in the form of salts of weak acids. The method also reflects physical differences in the quality of used substances. PMID:26959550

  2. Biphasic Investigation of Tissue Mechanical Response During Freezing Front Propagation

    PubMed Central

    Wright, Jamie; Han, Bumsoo; Chuong, Cheng-Jen

    2012-01-01

    Cryopreservation of engineered tissue (ET) has achieved limited success due to limited understanding of freezing-induced biophysical phenomena in ETs, especially fluid-matrix interaction within ETs. To further our understanding of the freezing-induced fluid-matrix interaction, we have developed a biphasic model formulation that simulates the transient heat transfer and volumetric expansion during freezing, its resulting fluid movement in the ET, elastic deformation of the solid matrix and the corresponding pressure redistribution within. Treated as a biphasic material, the ET consists of a porous solid matrix fully saturated with interstitial fluid. Temperature-dependent material properties were employed and phase change was included by incorporating the latent heat of phase change into an effective specific heat term. Model-predicted temperature distribution, the location of the moving freezing front, and the ET deformation rates through the time course compare reasonably well with experiments reported previously. Results from our theoretical model show that behind the marching freezing front, the ET undergoes expansion due to phase change of its fluid contents. It compresses the region preceding the freezing front leading to its fluid expulsion and reduced regional fluid volume fractions. The expelled fluid is forced forward and upward into the region further ahead of the compression zone causing a secondary expansion zone; which then compresses the region further downstream with much reduced intensity. Overall, it forms an alternating expansion-compression pattern which moves with the marching freezing front. The present biphasic model helps us to gain insights into some facets of the freezing process and cryopreservation treatment that could not be gleaned experimentally. Its resulting understanding will ultimately be useful to design and improve cryopreservation protocols for ETs. PMID:22757502

  3. Biphasic Effects of Alcohol as a Function of Circadian Phase

    PubMed Central

    Van Reen, Eliza; Rupp, Tracy L.; Acebo, Christine; Seifer, Ronald; Carskadon, Mary A.

    2013-01-01

    Study Objectives: To assess how alcohol affects multiple sleep latency tests (MSLT) and subjective measures of stimulation/sedation when alcohol is given at different circadian phases. Participants: Twenty-seven healthy young adults (age 21-26 yr) were studied. Design: Double-blind placebo and alcohol (vodka tonic targeting 0.05 g% concentration) beverages were each administered three times during the 20-h forced desynchrony protocol. Sleep latency tests and Biphasic Effects of Alcohol Scale (BAES) were administered on each forced desynchrony day. The outcome variables for this study include sleep onset latency (SOL) and stimulation and sedation value (from the BAES). Each outcome variable was associated with the ascending or descending limb of the breath alcohol concentration (BrAC) curve and assigned a circadian phase within a 90° bin. Measurements and Results: BrAC confirmed targeted maximal levels. Only outcome variables associated with the ascending and descending limb of the alcohol curve were analyzed for this article. Alcohol administered at a circadian time associated with greatest sleepiness showed longer SOL compared with placebo when measured on the ascending limb of the BrAC curve. We also found longer SOL with alcohol on the ascending limb of the BrAC curve in a circadian bin that favors greatest alertness. We observed shorter SOLs on the descending limb of the BrAC curve, but with no circadian phase interaction. The subjective data were partially consistent with the objective data. Conclusions: The physiologic findings in this study support the biphasic stimulating and sedating properties of alcohol, but limit the effect to specific circadian times. Citation: Van Reen E; Rupp TL; Acebo C; Seifer R; Carskadon MA. Biphasic effects of alcohol as a function of circadian phase. SLEEP 2013;36(1):137-145. PMID:23288980

  4. Management of Benign Biliary Strictures

    SciTech Connect

    Laasch, Hans-Ulrich; Martin, Derrick F.

    2002-12-15

    Benign biliary strictures are most commonly a consequence of injury at laparoscopic cholecystectomy or fibrosis after biliary-enteric anastomosis. These strictures are notoriously difficult to treat and traditionally are managed by resection and fashioning of acholedocho- or hepato-jejunostomy. Promising results are being achieved with newer minimally invasive techniques using endoscopic or percutaneous dilatation and/or stenting and these are likely to play an increasing role in the management. Even low-grade biliary obstruction carries the risks of stone formation, ascending cholangitis and hepatic cirrhosis and it is important to identify and treat this group of patients. There is currently no consensus on which patient should have what type of procedure, and the full range of techniques may not be available in all hospitals. Careful assessment of the risks and likely benefits have to be made on an individual basis. This article reviews the current literature and discusses the options available. The techniques of endoscopic and percutaneous dilatation and stenting are described with evaluation of the likely success and complication rates and compared to the gold standard of biliary-enteric anastomosis.

  5. Benign hereditary chorea: an update.

    PubMed

    Inzelberg, Rivka; Weinberger, Moran; Gak, Eva

    2011-06-01

    Benign hereditary chorea (BHC, MIM 118700) is a rare autosomal dominant disorder manifesting with chorea in conjunction with hypothyroidism and respiratory problems, a triad also named "brain-lung-thyroid syndrome". BHC is characterized by childhood onset with minimal or no progression into adult life and normal cognitive function. The genetic basis of BHC has been partially resolved, when mutations in the TTF1 gene on chromosome 14q13 encoding the thyroid transcription factor-1 have been identified in a number of BHC patients, suggesting that aberration of TTF1 transcriptional function or haploinsufficiency is associated with this disorder. TTF1 (also known as TITF1, TEBP or NKX2-1), belonging to the NKX2 homeodomain transcription factor family, has been implicated in several important molecular pathways essential for brain, thyroid and lung morphogenesis. Clinical evaluation of TTF1 gene mutations carrier patients exposed the involvement of each of the triad's components characterized by heterogeneity between index cases and even within families. This review highlights the current updates on expanded clinical aspects of BHC, imaging and treatment experience, its genetic markers, proposed molecular mechanisms, animal models and link to cancer. PMID:21292530

  6. A simple biphasic route to water soluble dithiocarbamate functionalized quantum dots

    SciTech Connect

    Wang, J.; Xu, J.; Goodman, M.; Chen, Y.; Cai, M.; Shinar, J.; Lin, Z.

    2008-06-11

    Hydrophobic trioctylphosphine oxide-functionalized CdSe quantum dots (CdSe-TOPO QDs) were transferred from organic solvent to aqueous solution via a simple yet novel biphasic ligand exchange process in one step, which involved the in-situ formation of hydrophilic dithiocarbamate moieties and subsequent ligand exchange with TOPO at the chloroform/water interface. The resulting water dispersible, dithiocarbamate functionalized CdSe QDs (i.e., D-CdSe) exhibited an increased photoluminescence (PL) quantum yield as compared to the original CdSe-TOPO QDs, suggesting an effective passivation of dithiocarbamate ligands on the QD surface. The D-CdSe QDs were then mixed with hydroxyl terminated TiO{sub 2} nanoparticles. A decrease in the PL of the mixture was observed, indicating a possible charge transfer from the D-CdSe QDs to the TiO{sub 2} nanoparticles. The reaction of the carboxyl group on the D-CdSe surface with the hydroxyl group on the TiO{sub 2} rendered QDs in direct contact with TiO{sub 2}, thereby facilitating the electronic interaction between them.

  7. Endoscopic management of benign tracheobronchial tumors

    PubMed Central

    Gao, Hui; Ding, Xin; Wei, Dong; Cheng, Peng; Su, Xiaomei; Liu, Huanyi; Zhang, Tao

    2011-01-01

    Even though benign tracheobronchial tumors are quite rare, they still can induce airway obstruction, result in suffocation, and need emergent management to remove the obstructing lesions and make the respiratory tracts unobstructed. Although the preferred therapy is surgery, it is still difficult to deal with the tumors in some cases, and the complications of surgery are common. Therefore, bronchoscopic managements, such as Nd: YAG laser, electrocautery, APC and Cryotherapy, are very important to treat benign tracheobronchial tumors and can cure most of them. The efficacy of therapeutic endoscopy for the treatment of patients with benign airways obstruction has been established. However, in order to maximally eradicate the benign tumors with minimal damage to patients, the success of bronchoscopic managements for the treatment strongly depends on the diligent identification of the various factors, including the location, size, shape of tumor, and the age, status, cardio respiratory function of patients, and full comprehension of the limits and potential of each particular technique. Because the advantages and disadvantages of above mentioned interventional methods, single method can not solve all clinical issues. Therefore, in order to remove benign tracheobronchial tumors completely, and reduce the incidence of recurrence as far as possible, many doctors combine several methods of them to treat complicated benign tracheobronchial tumors. This article reviews the core principles and techniques available to the bronchoscope managing benign tracheobronchial tumors. PMID:22263100

  8. Organic aqueous tunable solvents (OATS): a vehicle for coupling reactions and separations.

    PubMed

    Pollet, Pamela; Hart, Ryan J; Eckert, Charles A; Liotta, Charles L

    2010-09-21

    In laboratory-based chemical synthesis, the choice of the solvent and the means of product purification are rarely determined by cost or environmental impact considerations. When a reaction is scaled up for industrial applications, however, these choices are critical: the separation of product from the solvent, starting materials, and byproduct usually constitutes 60-80% of the overall cost of a process. In response, researchers have developed solvents and solvent-handling methods to optimize both the reaction and the subsequent separation steps on the manufacturing scale. These include "switchable" solvents, which are designed so that their physical properties can be changed abruptly, as well as "tunable" solvents, wherein the solvent's properties change continuously through the application of an external stimulus. In this Account, we describe the organic aqueous tunable solvent (OATS) system, examining two instructive and successful areas of application of OATS as well as its clear potential for further refinement. OATS systems address the limitations of biphasic processes by optimizing reactions and separations simultaneously. The reaction is performed homogeneously in a miscible aqueous-organic solvent mixture, such as water-tetrahydrofuran (THF). The efficient product separation is conducted heterogeneously by the simple addition of modest pressures of CO(2) (50-60 bar) to the system. Under these conditions, the water-THF phase splits into two relatively immiscible phases: the organic THF phase contains the hydrophobic product, and the aqueous phase contains the hydrophilic catalyst. We take advantage of the unique properties of OATS to develop environmentally benign and cost-competitive processes relevant in industrial applications. Specifically, we describe the use of OATS for optimizing the reaction, separation, design, and recycling of (i) Rh-catalyzed hydroformylation of olefins such as 1-octene and (ii) enzyme-catalyzed hydrolysis of 2-phenylacetate. We

  9. Biphasic patterns of diversification and the emergence of modules

    PubMed Central

    Mittenthal, Jay; Caetano-Anollés, Derek; Caetano-Anollés, Gustavo

    2012-01-01

    The intricate molecular and cellular structure of organisms converts energy to work, which builds and maintains structure. Evolving structure implements modules, in which parts are tightly linked. Each module performs characteristic functions. In this work we propose that a module can emerge through two phases of diversification of parts. Early in the first phase of this biphasic pattern, the parts have weak linkage—they interact weakly and associate variously. The parts diversify and compete. Under selection for performance, interactions among the parts increasingly constrain their structure and associations. As many variants are eliminated, parts self-organize into modules with tight linkage. Linkage may increase in response to exogenous stresses as well as endogenous processes. In the second phase of diversification, variants of the module and its functions evolve and become new parts for a new cycle of generation of higher-level modules. This linkage hypothesis can interpret biphasic patterns in the diversification of protein domain structure, RNA and protein shapes, and networks in metabolism, codes, and embryos, and can explain hierarchical levels of structural organization that are widespread in biology. PMID:22891076

  10. Biphasic Analysis of Cartilage Stresses in the Patellofemoral Joint.

    PubMed

    Jones, Brian; Hung, Clark T; Ateshian, Gerard

    2016-02-01

    The objective of this study was to examine the state of stress within the solid matrix of articular cartilage in the patellofemoral joint, using anatomically faithful biphasic models of the articular layers, with the joint subjected to physiologic muscle force magnitudes. Finite element models of five joints were created from human cadaver knees. Biphasic sliding contact analyses were performed using FEBio software to analyze the response of the joint from 30 to 60 degrees of knee flexion. Results demonstrated that the collagen matrix always sustains tensile stresses, despite the fact that the articular layers are loaded in compression. The principal direction of maximum solid stresses was consistent with the known orientation of collagen fibrils in cartilage. The magnitudes of these tensile stresses under muscle forces representative of activities of daily living were well below tensile failure stresses reported in the prior literature. Results also hinted that solid matrix stresses were higher in the patellar versus femoral superficial zone. These anatomically correct finite element models predicted outcomes consistent with our understanding of structure-function relationships in articular cartilage, while also producing solid matrix stress estimates not observable from experiments alone, yet highly relevant to our understanding of tissue degeneration. PMID:26641078

  11. Cell–material interactions on biphasic polyurethane matrix

    PubMed Central

    Dicesare, Patrick; Fox, Wade M.; Hill, Michael J.; Krishnan, G. Rajesh; Yang, Shuying; Sarkar, Debanjan

    2013-01-01

    Cell–matrix interaction is a key regulator for controlling stem cell fate in regenerative tissue engineering. These interactions are induced and controlled by the nanoscale features of extracellular matrix and are mimicked on synthetic matrices to control cell structure and functions. Recent studies have shown that nanostructured matrices can modulate stem cell behavior and exert specific role in tissue regeneration. In this study, we have demonstrated that nanostructured phase morphology of synthetic matrix can control adhesion, proliferation, organization and migration of human mesenchymal stem cells (MSCs). Nanostructured biodegradable polyurethanes (PU) with segmental composition exhibit biphasic morphology at nanoscale dimensions and can control cellular features of MSCs. Biodegradable PU with polyester soft segment and hard segment composed of aliphatic diisocyanates and dipeptide chain extender were designed to examine the effect polyurethane phase morphology. By altering the polyurethane composition, morphological architecture of PU was modulated and its effect was examined on MSC. Results show that MSCs can sense the nanoscale morphology of biphasic polyurethane matrix to exhibit distinct cellular features and, thus, signifies the relevance of matrix phase morphology. The role of nanostructured phases of a synthetic matrix in controlling cell–matrix interaction provides important insights for regulation of cell behavior on synthetic matrix and, therefore, is an important tool for engineering tissue regeneration. PMID:23255285

  12. Development and Characterization of Biphasic Hydroxyapatite/β-TCP Cements

    PubMed Central

    Gallinetti, Sara; Canal, Cristina; Ginebra, Maria-Pau; Ferreira, J

    2014-01-01

    Biphasic calcium phosphate bioceramics composed of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) have relevant properties as synthetic bone grafts, such as tunable resorption, bioactivity, and intrinsic osteoinduction. However, they have some limitations associated to their condition of high-temperature ceramics. In this work self-setting Biphasic Calcium Phosphate Cements (BCPCs) with different HA/β-TCP ratios were obtained from self-setting α-TCP/β-TCP pastes. The strategy used allowed synthesizing BCPCs with modulated composition, compressive strength, and specific surface area. Due to its higher solubility, α-TCP was fully hydrolyzed to a calcium-deficient HA (CDHA), whereas β-TCP remained unreacted and completely embedded in the CDHA matrix. Increasing amounts of the non-reacting β-TCP phase resulted in a linear decrease of the compressive strength, in association to the decreasing amount of precipitated HA crystals, which are responsible for the mechanical consolidation of apatitic cements. Ca2+ release and degradation in acidic medium was similar in all the BCPCs within the timeframe studied, although differences might be expected in longer term studies once β-TCP, the more soluble phase was exposed to the surrounding media. PMID:25866411

  13. Biphasic Ferrogels for Triggered Drug and Cell Delivery

    PubMed Central

    Cezar, Christine A.; Kennedy, Stephen M.; Mehta, Manav; Weaver, James C.; Gu, Luo; Vandenburgh, Herman

    2014-01-01

    Ferrogels are an attractive material for many biomedical applications due to their ability to deliver a wide variety of therapeutic drugs on-demand. However, typical ferrogels have yet to be optimized for use in cell-based therapies, as they possess limited ability to harbor and release viable cells. Previously, we have demonstrated an active porous scaffold that exhibits large deformations under moderate magnetic fields, resulting in enhanced biological agent release. However, at small device sizes optimal for implantation (e.g., 2 mm thickness), these monophasic ferrogels no longer achieve significant deformation due to a reduced body force. In this study, we present a new biphasic ferrogel containing an iron oxide gradient capable of large deformations and triggered release even at small gel dimensions. Biphasic ferrogels demonstrate increased porosity, enhanced mechanical properties, and potentially increased biocompatibility due to their reduced iron oxide content. With their ability to deliver drugs and cells on-demand, it is expected that these ferrogels will have wide utility in the fields of tissue engineering and regenerative medicine. PMID:24862232

  14. Biphasic cardiovascular and respiratory effects induced by β-citronellol.

    PubMed

    Ribeiro-Filho, Helder Veras; de Souza Silva, Camila Meirelles; de Siqueira, Rodrigo JoséBezerra; Lahlou, Saad; dos Santos, Armênio Aguiar; Magalhães, Pedro Jorge Caldas

    2016-03-15

    β-Citronellol is a monoterpene found in the essential oil of various plants with antihypertensive properties. In fact, β-citronellol possesses hypotensive actions due to its vasodilator abilities. Here we aimed to show that β-citronellol recruits airway sensory neural circuitry to evoke cardiorespiratory effects. In anesthetized rats, intravenous injection of β-citronellol caused biphasic hypotension, bradycardia and apnea. Bilateral vagotomy, perivagal capsaicin treatment or injection into the left ventricle abolished first rapid phase (named P1) but not delayed phase P2 of the β-citronellol effects. P1 persisted after pretreatment with capsazepine, ondansetron, HC-030031 or suramin. Suramin abolished P2 of apnea. In awake rats, β-citronellol induced biphasic hypotension and bradycardia being P1 abolished by methylatropine. In vitro, β-citronellol inhibited spontaneous or electrically-evoked contractions of rat isolated right or left atrium, respectively, and fully relaxed sustained contractions of phenylephrine in mesenteric artery rings. In conclusion, chemosensitive pulmonary vagal afferent fibers appear to mediate the cardiovascular and respiratory effects of β-citronellol. The transduction mechanism in P1 seems not to involve the activation of transient receptor potential vanilloid subtype 1 (TRPV1), transient receptor potential ankyrin subtype 1 (TRPA1), purinergic (P2X) or 5-HT3 receptors located on airways sensory nerves. P2 of hypotension and bradycardia seems resulting from a cardioinhibitory and vasodilatory effect of β-citronellol and the apnea from a purinergic signaling. PMID:26872991

  15. Cell-material interactions on biphasic polyurethane matrix.

    PubMed

    Dicesare, Patrick; Fox, Wade M; Hill, Michael J; Krishnan, G Rajesh; Yang, Shuying; Sarkar, Debanjan

    2013-08-01

    Cell-matrix interaction is a key regulator for controlling stem cell fate in regenerative tissue engineering. These interactions are induced and controlled by the nanoscale features of extracellular matrix and are mimicked on synthetic matrices to control cell structure and functions. Recent studies have shown that nanostructured matrices can modulate stem cell behavior and exert specific role in tissue regeneration. In this study, we have demonstrated that nanostructured phase morphology of synthetic matrix can control adhesion, proliferation, organization and migration of human mesenchymal stem cells (MSCs). Nanostructured biodegradable polyurethanes (PU) with segmental composition exhibit biphasic morphology at nanoscale dimensions and can control cellular features of MSCs. Biodegradable PU with polyester soft segment and hard segment composed of aliphatic diisocyanates and dipeptide chain extender were designed to examine the effect polyurethane phase morphology. By altering the polyurethane composition, morphological architecture of PU was modulated and its effect was examined on MSC. Results show that MSCs can sense the nanoscale morphology of biphasic polyurethane matrix to exhibit distinct cellular features and, thus, signifies the relevance of matrix phase morphology. The role of nanostructured phases of a synthetic matrix in controlling cell-matrix interaction provides important insights for regulation of cell behavior on synthetic matrix and, therefore, is an important tool for engineering tissue regeneration. PMID:23255285

  16. Biphasic behavior of energy in a stepped chain

    NASA Astrophysics Data System (ADS)

    Ping-Jian, Wang; Ai-Xiang, He; Zhong-Hai, Lin; Guang-Fen, Wei; Yan-Li, Liu

    2016-06-01

    The impact energy decay in a step-up chain containing two sections is numerically studied. There is a marked biphasic behavior of energy decay in the first section. Two sections close to the interface are in compression state. The degree of compression of the first section first decreases and becomes weakest at “crossing” time of biphasic behavior of energy, then increases. The further calculations provide the dependence of the character time on mass ratio (m 1/m 2), where m 1 and m 2 are the particle mass in the first and second section respectively. The bigger the α (α = [(Ωm 1 – m 2)/(Ωm 1 + m 2)]2 with Ω = 1.345), the bigger the energy ratio is. The multipulse structure restricts the transport of energy. Project supported by the National Natural Science Foundation of China (Grant Nos. 61174007 and 61307041) and the Natural Science Foundation of Shandong Province, China (Grant No. ZR2013AL014).

  17. Process for preparing organoclays for aqueous and polar-organic systems

    DOEpatents

    Chaiko, David J.

    2001-01-01

    A process for preparing organoclays as thixotropic agents to control the rheology of water-based paints and other aqueous and polar-organic systems. The process relates to treating low-grade clay ores to achieve highly purified organoclays and/or to incorporate surface modifying agents onto the clay by adsorption and/or to produce highly dispersed organoclays without excessive grinding or high shear dispersion. The process involves the treatment of impure, or run-of-mine, clay using an aqueous biphasic extraction system to produce a highly dispersed clay, free of mineral impurities and with modified surface properties brought about by adsorption of the water-soluble polymers used in generating the aqueous biphasic extraction system. This invention purifies the clay to greater than 95%.

  18. An augmented Lagrangian finite element formulation for 3D contact of biphasic tissues.

    PubMed

    Guo, Hongqiang; Spilker, Robert L

    2014-01-01

    Biphasic contact analysis is essential to obtain a complete understanding of soft tissue biomechanics, and the importance of physiological structure on the joint biomechanics has long been recognised; however, up to date, there are no successful developments of biphasic finite element contact analysis for three-dimensional (3D) geometries of physiological joints. The aim of this study was to develop a finite element formulation for biphasic contact of 3D physiological joints. The augmented Lagrangian method was used to enforce the continuity of contact traction and fluid pressure across the contact interface. The biphasic contact method was implemented in the commercial software COMSOL Multiphysics 4.2(®) (COMSOL, Inc., Burlington, MA). The accuracy of the implementation was verified using 3D biphasic contact problems, including indentation with a flat-ended indenter and contact of glenohumeral cartilage layers. The ability of the method to model multibody biphasic contact of physiological joints was proved by a 3D knee model. The 3D biphasic finite element contact method developed in this study can be used to study the biphasic behaviours of the physiological joints. PMID:23181617

  19. ENVIRONMENTALLY-BENIGN MULTIPHASE CATALYSIS. (R826034)

    EPA Science Inventory

    Environmental concerns stemming from the use of conventional solvents and from hazardous waste generation have propelled research efforts aimed at developing benign chemical processing techniques that either eliminate or significantly mitigate pollution at the source. This pap...

  20. Synthesis and Characterization of Environmentally Benign Nanoparticles

    EPA Science Inventory

    There has been a growing interest in replacing current non-biodegradable and toxic nanosystems with environmentally benign biopolymer based ones to minimize post-utilization hazards due to uncontrolled accumulation of nanoparticles in the environment. Lignin based nanoparticles (...

  1. Benign idiopathic partial epilepsy and brain lesion.

    PubMed

    Stephani, U; Doose, H

    1999-03-01

    A 14-year-old girl had severe head trauma from a dog bite at the age of 9 days. This resulted in extensive brain damage, tetraplegia, mental retardation, and epilepsy. The seizures were of rolandic type, and the EEG showed multifocal sharp waves. The course was benign. The initial diagnosis of a pure symptomatic epilepsy was revised after demonstrating typical benign focal sharp waves in the EEG of the healthy sister. Thus a phenocopy of a benign partial epilepsy by the brain lesion could be excluded with sufficient certainty. This observation allows the conclusion that the genetic disposition underlying the sharp-wave trait characteristic of benign partial epilepsies can be involved also in the pathogenesis of seemingly pure symptomatic epilepsies. EEG studies on siblings of such patients are needed to exclude possible phenocopies. PMID:10080522

  2. Aqueous production.

    PubMed

    Krupin, T; Wax, M; Moolchandani, J

    1986-01-01

    The formation of aqueous humour by the ciliary body is a complex process. Active transport of solutes by the ciliary process epithelium is an energy-dependent mechanism that selectively transports substances against an electrochemical gradient across the cell membranes. Water passively follows the active solute transport. In addition to these active transport processes, ultrafiltration contributes to the formation of aqueous humour. The ciliary epithelium contains enzyme systems that function in the production of aqueous humour. The enzymes sodium-potassium-activated adenosine triphosphatase [(Na+:K+)ATPase] and carbonic anhydrase participate in the active transport across this epithelium. Inhibition of these enzymes lowers intraocular pressure (IOP) by decreasing aqueous humour production. the ciliary epithelium contains both alpha- and beta-adrenergic receptors. Electrophysiologic studies on the isolated iris-ciliary body (I-CB) preparation provide a means to study direct effects of the adrenergic agents on transepithelial properties of the ciliary epithelium. This paper will discuss the enzymatic and adrenergic properties of the ciliary epithelium as they relate to active transport and thereby aqueous humour production. PMID:3026067

  3. Process for recovering chaotropic anions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, R.; Horwitz, E.P.; Bond, A.H.

    1999-03-30

    A solid/liquid process for the separation and recovery of chaotropic anions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the chaotropic anions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt (lyotrope). A solid/liquid phase admixture of separation particles containing bound chaotropic anions in such an aqueous solution is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture. 19 figs.

  4. Bioplastique: a new biphasic polymer for minimally invasive injection implantation.

    PubMed

    Ersek, R A; Beisang, A A

    1992-01-01

    The search for prosthetic materials that are biocompatible, nontoxic, and permanent led the authors to develop a micronized, inert, biphasic polymer particle for permanent soft tissue augmentation which neither migrates nor is absorbed by the body. Placed in a bioexcretable gel carrier, these textured microparticles are easily implanted using a specially designed blunt-tipped cannula with local anesthesia on an outpatient basis. Research using this implant material, Bioplastique (Bioplasty, St. Paul, MN), in rabbits has shown that when the textured particle size is maintained within a critical range, neither particle migration nor storage disease occurs. The gel carrier is rapidly phagocytized and replaced by fibrin matrix within a few days. Host collagen then gradually forms a fibrotic capsule around each textured particle, making use of the naturally occurring foreign body reaction to create a stable inplant. After being followed for over two years, Bioplastique has proven to be useful in many clinical applications with few complications. PMID:1734632

  5. On optimization of integration properties of biphase coded signals

    NASA Astrophysics Data System (ADS)

    Qiu, Wanzhi; Xiang, Jingcheng

    Within the context of the requirements for agile waveforms with a large compression ratio in biphase coded radars and on the basis of the characteristics of interpulse integration processing of radar signals, the study proposes two sequence optimization criteria which are suitable for radar processing patterns: interpulse waveform agility - pulse compression - FFT, and MTI - pulse compression - noncoherent integration. Applications of these criteria to optimizing sequences of length 127 are carried out. The output peak ratio of mainlobe to sidelobe (RMS) is improved considerably without a weighting network, while the autocorrelation and cross correlation profles of the sequences are very satisfactory. The RMS of coherent integration and noncoherent integration of eight sequences are 34.12 and 28.1 dB, respectively, when the return signals have zero Doppler shift. These values are about 12 and 6 dB higher than the RMS of single signals before integration.

  6. Surface modification of biphasic calcium phosphate bioceramic powders

    NASA Astrophysics Data System (ADS)

    Yang, W. Z.; Zhou, D. L.; Yin, G. F.; Li, G. D.

    2008-11-01

    Biphasic calcium phosphate (BCP)/poly L-lactide (PLLA) biocomposite is proven to be a promising bone graft material or scaffold for bone tissue engineering. To improve the interfacial compatibility of BCP bioceramic with biopolymer-PLLA, BCP powders were surface-modified in different condition to graft polymer groups onto the surface of the BCP powders. L-lactide and L-lactic acid (LA) oligomer were used to modify the BCP surface with stannous octanoate (Sn(Oct) 2) and stannous chloride (SnCl 2) as catalyst, respectively. Results show that the surface modification effect is obvious and the amount of grafted organic group is above 6.5 wt.%. Sn(Oct) 2 and SnCl 2 are the optimal catalysts for the surface grafting reaction of L-lactide and L-LA oligomer, respectively. The surface grafting slightly increase the particle size of BCP powders and reduce the tendency for their agglomeration.

  7. Intervertebral Disk Tissue Engineering Using Biphasic Silk Composite Scaffolds

    PubMed Central

    Park, Sang-Hyug; Gil, Eun Seok; Cho, Hongsik; Mandal, Biman B.; Tien, Lee W.; Min, Byoung-Hyun

    2012-01-01

    Scaffolds composed of synthetic, natural, and hybrid materials have been investigated as options to restore intervertebral disk (IVD) tissue function. These systems fall short of the lamellar features of the native annulus fibrosus (AF) tissue or focus only on the nucleus pulposus (NP) tissue. However, successful regeneration of the entire IVD requires a combination approach to restore functions of both the AF and NP. To address this need, a biphasic biomaterial structure was generated by using silk protein for the AF and fibrin/hyaluronic acid (HA) gels for the NP. Two cell types, porcine AF cells and chondrocytes, were utilized. For the AF tissue, two types of scaffold morphologies, lamellar and porous, were studied with the porous system serving as a control. Toroidal scaffolds formed out of the lamellar, and porous silk materials were used to generate structures with an outer diameter of 8 mm, inner diameter of 3.5 mm, and a height of 3 mm (the interlamellar distance in the lamellar scaffold was 150–250 μm, and the average pore sizes in the porous scaffolds were 100–250 μm). The scaffolds were seeded with porcine AF cells to form AF tissue, whereas porcine chondrocytes were encapsulated in fibrin/HA hydrogels for the NP tissue and embedded in the center of the toroidal disk. Histology, biochemical assays, and gene expression indicated that the lamellar scaffolds supported AF-like tissue over 2 weeks. Porcine chondrocytes formed the NP phenotype within the hydrogel after 4 weeks of culture with the AF tissue that had been previously cultured for 2 weeks, for a total of 6 weeks of cultivation. This biphasic scaffold simulating in combination of both AF and NP tissues was effective in the formation of the total IVD in vitro. PMID:21919790

  8. Biphasic Role of Calcium in Mouse Sperm Capacitation Signaling Pathways

    PubMed Central

    Alvau, Antonio; Escoffier, Jessica; Krapf, Dario; Sánchez-Cárdenas, Claudia; Salicioni, Ana M.; Darszon, Alberto; Visconti, Pablo E.

    2016-01-01

    Mammalian sperm acquire fertilizing ability in the female tract in a process known as capacitation. At the molecular level, capacitation is associated with up-regulation of a cAMP-dependent pathway, changes in intracellular pH, intracellular Ca2+ and an increase in tyrosine phosphorylation. How these signaling systems interact during capacitation is not well understood. Results presented in this study indicate that Ca2+ ions have a biphasic role in the regulation of cAMP-dependent signaling. Media without added Ca2+ salts (nominal zero Ca2+) still contain micromolar concentrations of this ion. Sperm incubated in this medium did not undergo PKA activation or the increase in tyrosine phosphorylation suggesting that these phosphorylation pathways require Ca2+. However, chelation of the extracellular Ca2+ traces by EGTA induced both cAMP-dependent phosphorylation and the increase in tyrosine phosphorylation. The EGTA effect in nominal zero Ca2+ media was mimicked by two calmodulin antagonists, W7 and calmidazolium, and by the calcineurin inhibitor cyclosporine A. These results suggest that Ca2+ ions regulate sperm cAMP and tyrosine phosphorylation pathways in a biphasic manner and that some of its effects are mediated by calmodulin. Interestingly, contrary to wild type mouse sperm, sperm from CatSper1 KO mice underwent PKA activation and an increase in tyrosine phosphorylation upon incubation in nominal zero Ca2+ media. Therefore, sperm lacking Catsper Ca2+ channels behave as wild-type sperm incubated in the presence of EGTA. This latter result suggests that Catsper transports the Ca2+ involved in the regulation of cAMP-dependent and tyrosine phosphorylation pathways required for sperm capacitation. PMID:25597298

  9. Biphasic Presence of Fibrocytes in a Porcine Hypertrophic Scar Model

    PubMed Central

    Travis, Taryn E.; Mino, Matthew J.; Moffatt, Lauren T.; Mauskar, Neil A.; Prindeze, Nicholas J.; Ghassemi, Pejhman; Ramella-Roman, Jessica C.; Jordan, Marion H.; Shupp, Jeffrey W.

    2014-01-01

    Objective The duroc pig has been described as a promising animal model for use in the study of human wound healing and scar formation. However little is known about the presence and chronology of the fibrocyte cell population in the healing process of these animals. Methods Wounds known to form scar were created on red duroc swine (3“ × 3”) with a dermatome to a total depth of either 0.06“ or 0.09”. These wounds were allowed to heal completely and were biopsied at scheduled time points during the healing process. Biopsies were formalin-fixed and paraffin embedded for immunohistochemical analysis. Porcine-reactive antibodies to CD-45 and procollagen-1 and a human-reactive antibody to LSP-1 were used to detect the presence of fibrocytes in immunohistochemistry an immunocytochemistry. Results Initial immunohistochemical studies showed evidence of a biphasic presence of fibrocytes. Pigs with 0.06“ deep wounds showed positive staining for CD-45 and LSP-1 within highly cellular areas at days 2 and 4 after wounding. Additional animals with 0.09” deep wounds showed positive staining within similar areas at days 56, 70, and 113 after wounding. There was no immunohistochemical evidence of fibrocytes in skin biopsies taken at days 14, 28, or 42. Procollagen-1 staining was diffuse in all samples. Cultured cells stained for CD-45, LSP-1, and procollagen-1 by immunocytochemistry. Conclusions These data confirm that fibrocytes are indeed present in this porcine model. We conclude that these cells are present after initial wounding and later during scar formation and remodeling. We believe that this is evidence of a biphasic presence of fibrocytes, first as an acute response to skin wounding followed by later involvement in the remodeling process, prompted by continued inflammation in a deep partial thickness wound. PMID:25051518

  10. Benign Mesenchymal Stromal Cells in Human Sarcomas

    PubMed Central

    Morozov, Alexei; Downey, Robert J.; Healey, John; Moreira, Andre L.; Lou, Emil; Leung, Roland; Edgar, Mark; Singer, Samuel; LaQuaglia, Michael; Maki, Robert G.; Moore, Malcolm A.S.

    2010-01-01

    Purpose Recent evidence suggests that at least some sarcomas arise through aberrant differentiation of mesenchymal stromal cells (MSCs), but MSCs have never been isolated directly from human sarcoma specimens. Experimental Design We examined human sarcoma cell lines and primary adherent cultures derived from human sarcoma surgical samples for features of MSCs. We further characterized primary cultures as either benign or malignant by the presence of tumor-defining genetic lesions and tumor formation in immunocompromised mice. Results We show that a dedifferentiated liposarcoma cell line DDLS8817 demonstrates fat, bone and cartilage trilineage differentiation potential characteristic of MSCs. Primary sarcoma cultures have the morphology, surface immunophenotype and differentiation potential characteristic of MSCs. Surprisingly, many of these cultures are benign as they do not form tumors in mice and lack sarcoma-defining genetic lesions. Consistent with the recently proposed pericyte origin of MSCs in normal human tissues, sarcoma-derived benign MSCs express markers of pericytes and cooperate with endothelial cells in tube formation assays. In human sarcoma specimens, a subset of CD146-positive microvascular pericytes express CD105, an MSC marker, while malignant cells largely do not. In an in vitro co-culture model, sarcoma-derived benign MSCs as well as normal human pericytes markedly stimulate the growth of sarcoma cell lines. Conclusions Sarcoma-derived benign MSCs/pericytes represent a previously undescribed stromal cell type in sarcoma which may contribute to tumor formation. PMID:21138865

  11. Benign metastasizing leiomyoma of the lung

    PubMed Central

    2013-01-01

    Benign leiomyomas of the uterus are uncommonly found in association with benign smooth muscle tumors beyond the confines of the uterus. Benign metastasizing leiomyoma (BML) is a rare disease in which the lung is described to be the most afflicted extrauterine organ. We present a brief review of the literature, along with case reports for four patients who were followed up after resection of a pulmonary lesion or after pathological confirmation by biopsy. The clinical course of BML varies from chronic asymptomatic appearance to rapid progression, leading to respiratory failure and death. Our BML patients did not complain of pulmonary symptoms, such as cough, dyspnea, or chest tightness. Pathology revealed benign leiomyomas with no atypia and mitotic activity <5 per 10 high-power field. Immunohistochemical staining was positive for actin and desmin. A standard treatment for BML has not yet been established. Because of the hormone-sensitive characteristics of BML, treatments are based on hormonal manipulation along with either surgical or medical oophorectomy. Benign metastasizing leiomyoma can be observed in postmenopausal women. We observed four patients who did not receive adjuvant hormonal therapy because they were postmenopausal or perimenopausal. All patients are still healthy and show no evidence of recurrence or progression of the disease. PMID:24134076

  12. Role of calcium in biphasic immunomodulation by gamma-HCH (lindane) in mice.

    PubMed

    Meera, P; Tripathi, O; Kamboj, K K; Rao, P R

    1993-01-01

    gamma-HCH (Lindane) is reported to cause a biphasic immunomodulation-stimulation followed by suppression-after oral administration in mice. Role of calcium in this biphasic immunomodulation was assessed after 4, 12 and 24 wks of gamma-HCH administration. 45Ca-uptake was enhanced during the initial immunostimulation followed by decrease concomitant with immunosuppression. Lymphocyte proliferation was inhibited during both the phases of immune response by verapamil, a calcium channel blocker, and by trifluoperazine, a calmodulin inhibitor. These findings show an impairment of calcium homeostasis in lymphocytes culminating into the biphasic immunomodulatory effects of gamma-HCH. PMID:7680676

  13. Electron transport in zinc-blende wurtzite biphasic gallium nitride nanowires and GaNFETs

    DOE PAGESBeta

    Jacobs, Benjamin W.; Ayres, Virginia M.; Stallcup, Richard E.; Hartman, Alan; Tupta, Mary Ann; Baczewski, Andrew David; Crimp, Martin A.; Halpern, Joshua B.; He, Maoqi; Shaw, Harry C.

    2007-10-19

    Two-point and four-point probe electrical measurements of a biphasic gallium nitride nanowire and current–voltage characteristics of a gallium nitride nanowire based field effect transistor are reported. The biphasic gallium nitride nanowires have a crystalline homostructure consisting of wurtzite and zinc-blende phases that grow simultaneously in the longitudinal direction. There is a sharp transition of one to a few atomic layers between each phase. Here, all measurements showed high current densities. Evidence of single-phase current transport in the biphasic nanowire structure is discussed.

  14. Malignancy and the benign lymphoepithelial lesion.

    PubMed

    Batsakis, J G; Bernacki, E G; Rice, D H; Stebler, M E

    1975-02-01

    The benign lymphoepithelial lesion of salivary glands is now considered the histological hallmark of a variety of clinical and pathological disorders affecting salivary tissues. Malignancy arising in the lesion is uncommon, but may take origin in either the epithelial or lymphoreticular components. Lymphomas and pseudolymphomas associated with salivary gland lymphoepithelial lesions have been predominately extra-salivary and strongly correlated with Sjögren's syndrome. Epithelial malignancy has not been associated with autoimmunity and with few exceptions has been of the anaplastic type. This report presents two patients with intra-salivary lymphomas arising in a benign lymphoepithelial lesion of salivary glands and a patient with anaplastic carcinoma arising in the epithelial islands of the lesion. The fourth patient manifested pseudolymphomatous lymphoreticular hyperplasia in lung and submandibular gland and illustrates the possible multiple organ involvement that may occur in patients with benign lymphoepithelial lesion, even without clinical evidence of concommitant autoimmune disorders. PMID:1172885

  15. Radiofrequency ablation for benign thyroid nodules.

    PubMed

    Bernardi, S; Stacul, F; Zecchin, M; Dobrinja, C; Zanconati, F; Fabris, B

    2016-09-01

    Benign thyroid nodules are an extremely common occurrence. Radiofrequency ablation (RFA) is gaining ground as an effective technique for their treatment, in case they become symptomatic. Here we review what are the current indications to RFA, its outcomes in terms of efficacy, tolerability, and cost, and also how it compares to the other conventional and experimental treatment modalities for benign thyroid nodules. Moreover, we will also address the issue of treating with this technique patients with cardiac pacemakers (PM) or implantable cardioverter-defibrillators (ICD), as it is a rather frequent occurrence that has never been addressed in detail in the literature. PMID:27098804

  16. The Unusual but Benign in Pediatric Surgery

    PubMed Central

    Shandling, Barry

    1985-01-01

    The problem of what is normal and what is not is closely related to whether or not, if something is indeed abnormal, it matters. Anticipating the outcome will affect the management in infants and children of such relatively benign conditions as hydroceles, umbilical hernias, diseases of the male and female breasts, lymphadenopathy and the intact prepuce. Unnecessary investigations such as barium studies which do not affect management are inadvisable. Congenital torticollis and undescended testis, seemingly benign, must be appropriately treated, however, in order to avoid lifelong sequelae. PMID:21274156

  17. Osteoid osteoma and benign osteoblastoma in childhood.

    PubMed Central

    Black, J A; Levick, R K; Sharrard, W J

    1979-01-01

    Three cases of osteoid osteoma and one of benign osteoblastoma in children are described. The main complaint was severe pain which was worse at night; it was relieved by aspirin or other analgesics. The diagnosis was made on clinical and radiological grounds and was confirmed on histological examination of the central nidus removed at operation. The pain was relieved in the patients with osteoid osteoma, and it was very much less after operative removal of the benign osteoblastoma. Both conditions are probably variations of the same disease process, depending on the anatomical site and the type of bone affected. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:475430

  18. Benign Cystic Mesothelioma Misdiagnosed as Peritoneal Carcinomatosis

    PubMed Central

    Shin, Hyun Deok; Kim, Suk Bae

    2016-01-01

    Benign cystic mesothelioma (BCM) is a rare benign disease that forms multicystic masses in the abdomen, pelvis, and retroperitoneum. It occurs predominantly in young to middle-aged women. The majority of cases were associated with a history of abdominal or pelvic operation, a history of endometriosis, and pelvic inflammatory disease. We present a unique case of BCM which is different to the previous cases. The patient was a 52-year-old man showing features of peritoneal carcinomatosis accompanied by ascites on abdominal computed tomography scans. We herein report a case of BCM misdiagnosed with peritoneal carcinomatosis.

  19. Evaluation of a new biphasic culture system for the recovery of mycobacteria.

    PubMed

    Giger, T; Burkardt, H J

    1990-06-01

    A newly developed biphasic culture system (MB-Check) for recovery of mycobacteria was evaluated. The biphasic system consists of a bottle containing selective modified Middlebrook 7H9 broth and a mounted dip slide with chocolate agar and modified Middlebrook 7H11 agar with and without NAP. The system was compared with culture on two egg-based media, Lowenstein medium and a selective Gottsacker medium, using 995 routine specimens and 90 artificially seeded sputa. Mycobacterium tuberculosis was detected in 17 of the 995 routine specimens by the biphasic system and in 14 specimens by the egg-based media together. In the artificially seeded sputa the biphasic system showed higher sensitivity in detection of both tuberculosis complex and non-tuberculous mycobacteria than the egg-based media. The recovery times of the new system were comparable to those of the two conventional culture methods. PMID:2387296

  20. Generation of useful energy from process fluids using the biphase turbine

    NASA Astrophysics Data System (ADS)

    Helgeson, N. L.

    1981-01-01

    The six largest energy consuming industries in the United States were surveyed to determine the energy savings that could result from applying the Biphase turbine to industrial process streams. A national potential energy savings of 58 million barrels of oil per year (technical market) was identified. This energy is recoverable from flashing gas liquid process streams and is separate and distinct from exhaust gas waste heat recovery. The industries surveyed in this program were the petroleum chemical, primary metals, paper and pulp, stone-clay-glass, and food. It was required to determine the applicability of the Biphase turbine to flashing operations connected with process streams, to determine the energy changes associated with these flashes if carried out in a Biphase turbine, and to determine the suitability (technical and economical feasibility) of applying the Biphase turbine to these processes.

  1. Progressive and biphasic cardiac responses during extreme mountain ultramarathon.

    PubMed

    Maufrais, Claire; Millet, Grégoire P; Schuster, Iris; Rupp, Thomas; Nottin, Stéphane

    2016-05-15

    Investigations on the cardiac function consequences of mountain ultramarathon (MUM) >100 h are lacking. The present study assessed the progressive cardiac responses during the world's most challenging MUM (Tor des Géants; Italy; 330 km; 24,000 m of cumulative elevation gain). Resting echocardiographic evaluation of morphology, function, and mechanics of left and right ventricle (LV and RV) including speckle tracking echocardiography was conducted in 15 male participants (46 ± 13 yr) before (pre), during (mid; 148 km), and after (post) the race. Runners completed the race in 126 ± 15 h. From pre to post, the increase in stroke volume (SV) (103 ± 19 vs. 110 ± 23 vs. 116 ± 21 ml; P < 0.001 at pre, mid, and post) was concomitant to the increase in LV early filling (peak E; 72.9 ± 15.7 vs. 74.6 ± 13.1 vs. 82.1 ± 11.5 cm/s; P < 0.05). Left and right atrial end-diastolic areas, RV end-diastolic area, and LV end-diastolic volume were 12-19% higher at post compared with pre (P < 0.05). Resting heart rate and LV systolic strain rates demonstrated a biphasic adaptation with an increase from pre to mid (55 ± 8 vs. 72 ± 11 beats/min, P < 0.001) and a return to baseline values from mid to post (59 ± 8 beats/min). Significant correlations were found between pre-to-post percent changes in peak E and LV end-diastolic volume (r = 0.63, P < 0.05) or RV (r = 0.82, P < 0.001) or atrial end-diastolic areas (r = 0.83, P < 0.001). An extreme MUM induced a biphasic pattern of heart rate in parallel with specific cardiac responses characterized by a progressive increase in diastolic filling, biventricular volumes, and SV. The underlying mechanisms and their clinical implications remain challenging for the future. PMID:26921434

  2. Biphasic influence of dexamethasone exposure on embryonic vertebrate skeleton development

    SciTech Connect

    Cheng, Xin; Chen, Jian-long; Ma, Zheng-lai; Zhang, Zhao-long; Lv, Shun; Mai, Dong-mei; Liu, Jia-jia; Chuai, Manli; Lee, Kenneth Ka Ho; Wan, Chao; Yang, Xuesong

    2014-11-15

    increased in mesenchymal cell mass treated by low concentration of Dex. Mmp-13 expression was obviously up-regulated by Dex in both mesenchymal cells and primary chondrocyte cultures. And Col10a1 expression was also increased by Dex exposure in chondrocyte. In summary, we have revealed that different concentrations of Dex exposure during early gestation could exert a biphasic effect on vertebrate skeletal development. - Highlights: • Chick embryos occurred shortening of the long bone following Dex exposure. • Dex suppressed chondrocytes proliferation and promoted apoptosis. • Dex exposure decreased ALP production and up-regulated Runx-2 and Mmp-13. • Dex exhibited biphasic effects on chondrogenic proliferation and nodule formation. • The hypertrophy and ossification were accelerated by Dex both in vivo and in vitro.

  3. Benign Prostatic Hyperplasia: from Bench to Clinic

    PubMed Central

    Cho, Hee Ju

    2012-01-01

    Benign prostatic hyperplasia (BPH) is a prevalent disease, especially in old men, and often results in lower urinary tract symptoms (LUTS). This chronic disease has important care implications and financial risks to the health care system. LUTS are caused not only by mechanical prostatic obstruction but also by the dynamic component of obstruction. The exact etiology of BPH and its consequences, benign prostatic enlargement and benign prostatic obstruction, are not identified. Various theories concerning the causes of benign prostate enlargement and LUTS, such as metabolic syndrome, inflammation, growth factors, androgen receptor, epithelial-stromal interaction, and lifestyle, are discussed. Incomplete overlap of prostatic enlargement with symptoms and obstruction encourages focus on symptoms rather than prostate enlargement and the shifting from surgery to medicine as the treatment of BPH. Several alpha antagonists, including alfuzosin, doxazosin, tamsulosin, and terazosin, have shown excellent efficacy without severe adverse effects. In addition, new alpha antagonists, silodosin and naftopidil, and phosphodiesterase 5 inhibitors are emerging as BPH treatments. In surgical treatment, laser surgery such as photoselective vaporization of the prostate and holmium laser prostatectomy have been introduced to reduce complications and are used as alternatives to transurethral resection of the prostate (TURP) and open prostatectomy. The status of TURP as the gold standard treatment of BPH is still evolving. We review several preclinical and clinical studies about the etiology of BPH and treatment options. PMID:22468207

  4. CSF imaging in benign intracranial hypertension

    PubMed Central

    James, A. Everette; Harbert, J. C.; Hoffer, P. B.; DeLand, F. H.

    1974-01-01

    The cisternographic images in 10 patients with benign intracranial hypertension were reviewed. Nine were normal. Transfer of labelled tracer from the subarachnoid space was measured in five patients and was found to be abnormal in only two. The relation of these findings to the proposed pathophysiological alterations is discussed. Images

  5. Unusual Benign Tumors of the Breast

    PubMed Central

    Adrada, Beatriz E; Krishnamurthy, Savitri; Carkaci, Selin; Posleman-Monetto, Flavia E; Ewere, Adesuwa; Whitman, Gary J

    2015-01-01

    The purpose of this article is to describe the imaging characteristics of a variety of benign breast tumors that may be encountered in daily practice, in order to formulate an appropriate differential diagnosis and to establish concordance between the imaging and the pathologic findings, and to assist the clinician with appropriate management. PMID:26085959

  6. Facilitatory effect of paired-pulse stimulation by transcranial magnetic stimulation with biphasic wave-form.

    PubMed

    Julkunen, Petro; Järnefelt, Gustaf; Savolainen, Petri; Laine, Jarmo; Karhu, Jari

    2016-08-01

    Transcranial magnetic stimulation (TMS) is used to probe corticospinal excitability by stimulating the motor cortex. Our aim was to enhance the effects of biphasic TMS by coupling a suprathreshold test pulse and a following subthreshold priming pulse to induce short-interval intracortical facilitation (SICF), which is conventionally produced with monophasic TMS. Biphasic TMS could potentially induce the SICF effect with better energy-efficiency and with lower stimulus intensities. This would make the biphasic paired-pulses better applicable in patients with reduced cortical excitability. A prototype stimulator was built to produce biphasic paired-pulses. Resting motor thresholds (rMTs) from the right and left hand abductor pollicis brevis muscles, and the right tibialis anterior muscle of eight healthy volunteers were determined using single-pulse paradigm with neuronavigated TMS. The rMTs and MEPs were measured using single-pulses and three paired-pulse setups (interstimulus interval, ISI of 3, 7 or 15ms). The rMTs were lower and MEPs were higher with biphasic paired-pulses compared to single-pulses. The SICF effect was greatest at 3ms ISI. This suggests that the application of biphasic paired-pulses to enhance stimulation effects is possible. PMID:27215172

  7. Comparison between FEBio and Abaqus for biphasic contact problems.

    PubMed

    Meng, Qingen; Jin, Zhongmin; Fisher, John; Wilcox, Ruth

    2013-09-01

    Articular cartilage plays an important role in the function of diarthrodial joints. Computational methods have been used to study the biphasic mechanics of cartilage, and Abaqus has been one of the most widely used commercial software packages for this purpose. A newly developed open-source finite element solver, FEBio, has been developed specifically for biomechanical applications. The aim of this study was to undertake a direct comparison between FEBio and Abaqus for some practical contact problems involving cartilage. Three model types, representing a porous flat-ended indentation test, a spherical-ended indentation test, and a conceptual natural joint contact model, were compared. In addition, a parameter sensitivity study was also performed for the spherical-ended indentation test to investigate the effects of changes in the input material properties on the model outputs, using both FEBio and Abaqus. Excellent agreement was found between FEBio and Abaqus for all of the model types and across the range of material properties that were investigated. PMID:23804955

  8. A nonlinear biphasic viscohyperelastic model for articular cartilage.

    PubMed

    García, José Jaime; Cortés, Daniel Humberto

    2006-01-01

    Experiments on articular cartilage have shown nonlinear stress-strain curves under finite deformations as well as intrinsic viscous effects of the solid phase. The aim of this study was to propose a nonlinear biphasic viscohyperelastic model that combines the intrinsic viscous effects of the proteoglycan matrix with a nonlinear hyperelastic constitutive equation. The proposed equation satisfies objectivity and reduces for uniaxial loading to a solid type viscous model in which the actions of the springs are represented by the hyperelastic function proposed by Holmes and Mow [1990. J. Biomechanics 23, 1145-1156.]. Results of the model, that were efficiently implemented in an updated Lagrangian algorithm, were compared with experimental infinitesimal data reported by DiSilverstro and Suh [2001. J. Biomechanics 34, 519-525.] and showed acceptable fitting for the axial force (R(2)=0.991) and lateral displacement (R(2)=0.914) curves in unconfined compression as well as a good fitting of the axial indentation force curve (R(2)=0.982). In addition, the model showed an excellent fitting of finite-deformation confined compression stress relaxation data reported by Ateshian et al. [1997. J. Biomechanics 30, 1157-1164.] and Huang et al. [2005. J. Biomechanics 38, 799-809.] (R(2)=0.993 and R(2)=0.995, respectively). The constitutive equation may be used to represent the mechanical behavior of the proteoglycan matrix in a fiber reinforced model of articular cartilage. PMID:16316659

  9. Biphasic Effect of Rifampicin on Bilirubin- A Case Report

    PubMed Central

    Seshadri, Mandalam Subramanian

    2016-01-01

    Drug induced hepatitis is a major problem which a physician encounters in his clinical practice. In view of increasing incidence of tuberculosis in our country a large number of infected individuals are started on Antituberculous (ATT) drugs and rifampicin is invariably part of the regimen. One of the major adverse effects of ATT drugs is drug- induced hepatitis which is characterized by elevation of liver enzymes and bilirubin. Hepatotoxicity is usually idiosyncratic or dose-dependent. Rifampicin causes transient elevation of transaminases in 10-20 percent of individuals and this does not warrant dose adjustments of the drug. Rarely rifampicin can lead to severe hepatitis with hyperbilirubinaemia and marked elevations of SGOT and SGPT and in some patients this can be fatal. The exact mechanism of Rifampicin induced hepatotoxicity is not known but it is postulated to be due to idiosyncratic reaction to rifampicin metabolites which may be directly toxic or induce an immunologically mediated liver injury. Rarely rifampicin may cause hyperbilirubinaemia without enzyme elevation. Here we report a patient with bilateral pulmonary tuberculosis who developed transient severe indirect hyperbilirubinaemia on rifampicin. On review of relevant literature we find that rifampicin can have a biphasic effect on bilirubin, an initial increase in indirect bilirubin and later normalization of bilirubin. We have reported this case because of its rarity in clinical practice. PMID:27190870

  10. Finite element formulation of biphasic poroviscoelastic model for articular cartilage.

    PubMed

    Suh, J K; Bai, S

    1998-04-01

    The purpose of the present study was to develop a computationally efficient finite element model that could be useful for parametric analysis of the biphasic poroviscoelastic (BPVE) behavior of articular cartilage under various loading conditions. The articular cartilage was modeled as the BPVE mixture of a porous, linear viscoelastic, and incompressible solid and an inviscid and incompressible fluid. A finite element (FE) formulation of the BPVE model was developed using two different algorithms, the continuous and discrete spectrum relaxation functions for the viscoelasticity of the solid matrix. These algorithms were applied to the creep and stress relaxation responses to the confined compression of articular cartilage, and a comparison of their performances was made. It was found that the discrete spectrum algorithm significantly saved CPU time and memory, as compared to the continuous spectrum algorithm. The consistency analysis for the present FE formulation was performed in comparison with the IMSL, a commercially available numerical software package. It was found that the present FE formulation yielded consistent results in predicting model behavior, whereas the IMSL subroutine produced inconsistent results in the velocity field, and thereby in the strain calculation. PMID:10412380

  11. Comparison between FEBio and Abaqus for biphasic contact problems

    PubMed Central

    Jin, Zhongmin; Fisher, John; Wilcox, Ruth

    2013-01-01

    Articular cartilage plays an important role in the function of diarthrodial joints. Computational methods have been used to study the biphasic mechanics of cartilage, and Abaqus has been one of the most widely used commercial software packages for this purpose. A newly developed open-source finite element solver, FEBio, has been developed specifically for biomechanical applications. The aim of this study was to undertake a direct comparison between FEBio and Abaqus for some practical contact problems involving cartilage. Three model types, representing a porous flat-ended indentation test, a spherical-ended indentation test, and a conceptual natural joint contact model, were compared. In addition, a parameter sensitivity study was also performed for the spherical-ended indentation test to investigate the effects of changes in the input material properties on the model outputs, using both FEBio and Abaqus. Excellent agreement was found between FEBio and Abaqus for all of the model types and across the range of material properties that were investigated. PMID:23804955

  12. Biphasic Effect of Rifampicin on Bilirubin- A Case Report.

    PubMed

    Gopi, Manigandan; Seshadri, Mandalam Subramanian

    2016-04-01

    Drug induced hepatitis is a major problem which a physician encounters in his clinical practice. In view of increasing incidence of tuberculosis in our country a large number of infected individuals are started on Antituberculous (ATT) drugs and rifampicin is invariably part of the regimen. One of the major adverse effects of ATT drugs is drug- induced hepatitis which is characterized by elevation of liver enzymes and bilirubin. Hepatotoxicity is usually idiosyncratic or dose-dependent. Rifampicin causes transient elevation of transaminases in 10-20 percent of individuals and this does not warrant dose adjustments of the drug. Rarely rifampicin can lead to severe hepatitis with hyperbilirubinaemia and marked elevations of SGOT and SGPT and in some patients this can be fatal. The exact mechanism of Rifampicin induced hepatotoxicity is not known but it is postulated to be due to idiosyncratic reaction to rifampicin metabolites which may be directly toxic or induce an immunologically mediated liver injury. Rarely rifampicin may cause hyperbilirubinaemia without enzyme elevation. Here we report a patient with bilateral pulmonary tuberculosis who developed transient severe indirect hyperbilirubinaemia on rifampicin. On review of relevant literature we find that rifampicin can have a biphasic effect on bilirubin, an initial increase in indirect bilirubin and later normalization of bilirubin. We have reported this case because of its rarity in clinical practice. PMID:27190870

  13. Biphasic binding kinetics between FepA and its ligands.

    PubMed

    Payne, M A; Igo, J D; Cao, Z; Foster, S B; Newton, S M; Klebba, P E

    1997-08-29

    The Escherichia coli FepA protein is an energy- and TonB-dependent, ligand-binding porin that functions as a receptor for the siderophore ferric enterobactin and colicins B and D. We characterized the kinetic and thermodynamic parameters associated with the initial, energy-independent steps in ligand binding to FepA. In vivo experiments produced Kd values of 24, 185, and 560 nM for ferric enterobactin, colicin B, and colicin D, respectively. The siderophore and colicin B bound to FepA with a 1:1 stoichiometry, but colicin D bound to a maximum level that was 3-fold lower. Preincubation with ferric enterobactin prevented colicin B binding, and preincubation with colicin B prevented ferric enterobactin binding. Colicin B release from FepA was unexpectedly slow in vivo, about 10-fold slower than ferric enterobactin release. This slow dissociation of the colicin B.FepA complex facilitated the affinity purification of FepA and FepA mutants with colicin B-Sepharose. Analysis of a fluorescent FepA derivative showed that ferric enterobactin and colicin B adsorbed with biphasic kinetics, suggesting that both ligands bind in at least two distinct steps, an initial rapid stage and a subsequent slower step, that presumably establishes a transport-competent complex. PMID:9268330

  14. Neutron Polarization Analysis for Biphasic Solvent Extraction Systems

    DOE PAGESBeta

    Motokawa, Ryuhei; Endo, Hitoshi; Nagao, Michihiro; Heller, William T.

    2016-06-16

    Here we performed neutron polarization analysis (NPA) of extracted organic phases containing complexes, comprised of Zr(NO3)4 and tri-n-butyl phosphate, which enabled decomposition of the intensity distribution of small-angle neutron scattering (SANS) into the coherent and incoherent scattering components. The coherent scattering intensity, containing structural information, and the incoherent scattering compete over a wide range of magnitude of scattering vector, q, specifically when q is larger than q* ≈ 1/Rg, where Rg is the radius of gyration of scatterer. Therefore, it is important to determine the incoherent scattering intensity exactly to perform an accurate structural analysis from SANS data when Rgmore » is small, such as the aforementioned extracted coordination species. Although NPA is the best method for evaluating the incoherent scattering component for accurately determining the coherent scattering in SANS, this method is not used frequently in SANS data analysis because it is technically challenging. In this study, we successfully demonstrated that experimental determination of the incoherent scattering using NPA is suitable for sample systems containing a small scatterer with a weak coherent scattering intensity, such as extracted complexes in biphasic solvent extraction systems.« less

  15. Dynamin 2 regulates biphasic insulin secretion and plasma glucose homeostasis

    PubMed Central

    Fan, Fan; Ji, Chen; Wu, Yumei; Ferguson, Shawn M.; Tamarina, Natalia; Philipson, Louis H.; Lou, Xuelin

    2015-01-01

    Alterations in insulin granule exocytosis and endocytosis are paramount to pancreatic β cell dysfunction in diabetes mellitus. Here, using temporally controlled gene ablation specifically in β cells in mice, we identified an essential role of dynamin 2 GTPase in preserving normal biphasic insulin secretion and blood glucose homeostasis. Dynamin 2 deletion in β cells caused glucose intolerance and substantial reduction of the second phase of glucose-stimulated insulin secretion (GSIS); however, mutant β cells still maintained abundant insulin granules, with no signs of cell surface expansion. Compared with control β cells, real-time capacitance measurements demonstrated that exocytosis-endocytosis coupling was less efficient but not abolished; clathrin-mediated endocytosis (CME) was severely impaired at the step of membrane fission, which resulted in accumulation of clathrin-coated endocytic intermediates on the plasma membrane. Moreover, dynamin 2 ablation in β cells led to striking reorganization and enhancement of actin filaments, and insulin granule recruitment and mobilization were impaired at the later stage of GSIS. Together, our results demonstrate that dynamin 2 regulates insulin secretory capacity and dynamics in vivo through a mechanism depending on CME and F-actin remodeling. Moreover, this study indicates a potential pathophysiological link between endocytosis and diabetes mellitus. PMID:26413867

  16. Macrophage and osteoblast responses to biphasic calcium phosphate microparticles.

    PubMed

    Fellah, Borhane Hakim; Delorme, Bruno; Sohier, Jérôme; Magne, David; Hardouin, Pierre; Layrolle, Pierre

    2010-06-15

    The aim of this work was to investigate in vitro the biological events leading to ectopic bone formation in contact with microporous biphasic calcium phosphate (BCP) ceramics. After implantation, microparticles may arise from their degradation and induce an inflammatory response involving macrophages. The secretion of pro-inflammatory cytokines may affect the differentiation of osteoblasts. Mouse macrophage-like (J774) and osteoblast-like (MC3T3-E1) cells were cultured in the presence of BCP microparticles of different sizes (<20, 40-80, or 80-200 microm). The smallest microparticles decreased the viability of both cell types as measured with LDH and methyl tetrazolium salt assays, and enhanced the secretion of pro-inflammatory cytokines (IL-6 and TNF-alpha) by macrophages after 24 h, as revealed by ELISA. Osteoblastic cells were then cultured for 96 h in the presence of these pro-inflammatory cytokines and their differentiation studied by RT-PCR. MC3T3-E1 cells cultured with TNF-alpha showed a decrease in osterix, PTH receptor (PTHR1), and osteocalcin gene expression. On the contrary, IL-6 enhanced the expression of osterix, Runx2, alkaline phosphatase, and osteocalcin compared with plastic. In conclusion, this study shows that the inflammatory response initiated by BCP microparticles may have both detrimental and beneficial effects on osteogenesis. PMID:20014296

  17. Isolated benign primary cutaneous plasmacytosis in a child.

    PubMed

    On, Hye Rang; Lee, Sang Eun; Kim, You Chan; Kim, Soo-Chan

    2014-01-01

    Isolated benign primary cutaneous plasmacytosis in a child is a very rare and benign disease. Herein we present a case of this condition occurring in a child who showed good response to topical corticosteroid. PMID:25424220

  18. [BENIGN TUMORS OF MEDIASTINUM: CLINIC, DIAGNOSIS, SURGICAL TREATMENT].

    PubMed

    Kalabukha, I A; Mayetniy, E M

    2015-12-01

    Results of surgical treatment of 18 patients in a thoracic surgery clinic for benign tumors of mediastinum are presented. The symptoms of benign tumors, efficacy of application of welding technologies in operative intervention were analyzed. PMID:27025028

  19. A novel benign solution for collagen processing

    NASA Astrophysics Data System (ADS)

    Arnoult, Olivier

    Collagen is the main protein constituting the extracellular matrix (ECM) of tissues in the body (skin, cartilage, blood vessels...). It exists many types of collagen, this work studies only fibrillar collagen (e.g. collagen type I contained in the skin) that exhibits a triple helical structure composed of 3 alpha-helical collagen chains. This particular and defined hierarchical structure is essential to the biological and mechanical properties of the collagen. Processing collagen into scaffolds to mimic the ECM is crucial for successful tissue engineering. Recently collagen was processed into fibrous and porous scaffold using electrospinning process. However the solvent (HFIP) used for electrospinning is extremely toxic for the user and expensive. This work shows that HFIP can be replaced by a benign mixture composed of water, salt and alcohol. Yet only three alcohols (methanol, ethanol and iso-propanol) enable the dissolution of large quantity of collagen in the benign mixture, with a wide range of alcohol to buffer ratio, and conserve the collagen hierarchical structure at least as well as the HFIP. Collagen can be electrospun from the benign mixture into sub-micron fibers with concentrations as low as 6 wt-% for a wide range of alcohol to buffer ratio, with at least 10wt-% of salt, and any of the three alcohols. Specific conditions yield nano size fibers. After processing from HFIP or a benign mixture, collagen is water soluble and needs to be chemically crosslink for tissue engineering application. Post-crosslinking with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) results in the loss of the scaffold fibrous aspect and porosity, hence it is useless for tissue engineering. Such issue could be prevented by incorporating the crosslinker into the mixture prior to electrospinning. When EDC is used alone, collagen forms a gel in the mixture within minutes, preventing electrospinning. The addition of N-hydroxysuccinimide (NHS) in excess to EDC

  20. Biphasic Peptide Amphiphile Nanomatrix Embedded with Hydroxyapatite Nanoparticles for Stimulated Osteoinductive Response

    PubMed Central

    Anderson, Joel M.; Patterson, Jessica L.; Vines, Jeremy B.; Javed, Amjad; Gilbert, Shawn R.; Jun, Ho-Wook

    2013-01-01

    Formation of the native bone extracellular matrix (ECM) provides an attractive template for bone tissue engineering. The structural support and biological complexity of bone ECM are provided within a composite microenvironment that consists of an organic fibrous network reinforced by inorganic hydroxyapatite (HA) nanoparticles. Recreating this biphasic assembly, a bone ECM analogous scaffold comprised of self-assembling peptide amphiphile (PA) nanofibers and interspersed HA nanoparticles was investigated. PAs were endowed with biomolecular ligand signaling using a synthetically inscribed peptide sequence (i.e. RGDS) and integrated with HA nanoparticles to form a biphasic nanomatrix hydrogel. It was hypothesized the biphasic hydrogel would induce osteogenic differentiation of human mesenchymal stem cells (hMSCs) and improve bone healing as mediated by RGDS ligand signaling within PA nanofibers and embedded HA mineralization source. Viscoelastic stability of the biphasic PA hydrogels was evaluated with different weight concentrations of HA for improved gelation. After demonstrating initial viability, long-term cellularity and osteoinduction of encapsulated hMSCs in different PA hydrogels were studied in vitro. Temporal progression of osteogenic maturation was assessed by gene expression of key markers. A preliminary animal study demonstrated bone healing capacity of the biphasic PA nanomatrix under physiological conditions using a critical size femoral defect rat model. The combination of RGDS ligand signaling and HA nanoparticles within the biphasic PA nanomatrix hydrogel demonstrated the most effective osteoinduction and comparative bone healing response. Therefore, the biphasic PA nanomatrix establishes a well-organized scaffold with increased similarity to natural bone ECM with the prospect for improved bone tissue regeneration. PMID:22077993

  1. Biphasic forearm vascular responses to intraarterial arginine vasopressin.

    PubMed Central

    Suzuki, S; Takeshita, A; Imaizumi, T; Hirooka, Y; Yoshida, M; Ando, S; Nakamura, M

    1989-01-01

    Forearm vascular responses to arginine vasopressin (AVP) infused into a brachial artery in a wide range of infusion rates (0.05-2.0 ng/kg per min) were examined in 20 young healthy volunteers. Intraarterial AVP at lower doses (0.05 and 0.1 ng/kg per min) caused forearm vasoconstriction, whereas AVP at a dose of 0.2 ng/kg per min or higher caused forearm vasodilatation. The maximal forearm vasoconstriction was induced at the venous plasma AVP level of 76.3 +/- 8.8 pg/ml. Forearm vasodilatation was associated with the venous plasma AVP level of 369 +/- 43 pg/ml or higher. Forearm vasodilatation was the result of the direct effect of AVP since forearm blood flow and vascular resistance in the contralateral arm did not change. We attempted to explore the mechanisms involved in AVP-induced direct vasodilatation. The treatment with indomethacin, 75 mg/d for 3 d, did not alter AVP-induced forearm vasodilatation. In contrast, intraarterial infusion of isoosmolar CaCl2 totally prevented AVP-induced forearm vasodilatation. Intra-arterial CaCl2 also markedly attenuated forearm vasodilatation induced by intraarterial sodium nitroprusside, but did not alter forearm vasodilatation induced by intraarterial isoproterenol. These results indicate that the direct vascular effects of intra-arterial AVP on the forearm vessels are biphasic, causing vasoconstriction at lower doses and vasodilatation at higher doses. The direct vasodilatation induced by intraarterial AVP at higher doses is not mediated by prostaglandins but may involve cGMP-related mechanisms. PMID:2547832

  2. Design and characterization of cefuroxime axetil biphasic floating minitablets.

    PubMed

    Jammula, Sruti; Patra, Ch Niranjan; Swain, Suryakanta; Panigrahi, Kanhu Charan; Nayak, Sabita; Dinda, Subas Chandra; Rao, Muddana Eswara Bhanoji

    2015-01-01

    Biphasic floating minitablets of cefuroxime axetil were prepared by melt granulation technique using two different grades of gelucire namely 50/13 and 43/01 to maintain constant plasma drug concentration. Loading dose of cefuroxime axetil was formulated as immediate release (IR) minitablets by using hydrophilic grade of gelucire 50/13. Maintenance dose was formulated as floating sustained release (SR) minitablets by using hydrophobic grade of gelucire 43/01. The prepared IR and SR granules were subjected to micromeritic studies and scanning electron microscopy. Fourier transform infrared spectroscopy (FT-IR) study revealed that drug and selected carriers were compatible. In vitro dissolution study of optimized IR minitablets showed more than 85% of loading dose dissolved within 30 min. Optimized SR minitablets showed zero lag time with floating duration more than 12 h. The drug release from SR minitablets was linear with square root of time with non-Fickian diffusion-controlled release. The optimized batch of minitablets was filled into 0 size hard gelatin capsule. In vitro dissolution study for capsule showed an immediate burst release followed by SR up to 12 h. There is no significant change in dissolution data after storage at 40 °C and 75% RH for three months. Microbiological assay of dissolution samples of optimized minitablets filled in capsules showed proportionate increase in inhibition of growth against Escherichia coli up to 12 h samples. In vivo bioavailability study in albino rabbits showed three times improvement in oral bioavailability. PMID:24417642

  3. Benign Diseases and Neoplasms of the Penis.

    PubMed

    Wasco, Matthew J; Shah, Rajal B

    2009-03-01

    This article provides comprehensive review of benign diseases and neoplastic conditions of the penis. It describes and provides representative images of clinical, key pathologic features and ancillary techniques to aid in differential diagnoses. It examines these diseases from the epidemiologic standpoint, looks at environmental and genetic factors, and outlines the new histologic entities for penile neoplasms with distinct outcomes and clinical behavior that have been proposed in recent years. PMID:26838101

  4. [Surgery of benign vocal fold lesions].

    PubMed

    Olthoff, A

    2016-09-01

    Surgical treatment of benign vocal fold lesions can be indicated for clinical or functional reasons. The principles of phonosurgery have to be maintained in either case. The appropriate phonosurgical technique depends on the type of vocal fold lesion. Depending on the findings, phonosurgery aims to maintain or improve voice quality. The evaluation of clinical and functional results includes indirect laryngoscopy, videostroboscopy, and voice analysis. PMID:27552826

  5. A benign maxillary tumour with malignant features.

    PubMed

    Ricalde, Rosario R; Lim, Aimee Caroline E; Lopa, Ramon Antonio B; Carnate, Jose M

    2010-06-01

    Non-specific biopsy results such as chronic inflammation, hemorrhage, necrosis can be frustrating to the clinician. This is especially true if the patient presents with clinical features suggestive of an aggressive tumour. This is a review of the clinical features, diagnostic dilemmas and surgical management of a benign maxillary mass with malignant features - a disease called hematoma-like mass of the maxillary sinus (HLMMS). Our experience with five cases will also be cited. PMID:20502750

  6. Large Penile Mass With Unusual Benign Histopathology.

    PubMed

    Johnson, Nate; Voznesensky, Maria; VerLee, Graham

    2015-09-01

    Pseudoepitheliomatous hyperplasia is an extremely rare condition presenting as a lesion on the glans penis in older men. Physical exam without biopsy cannot differentiate malignant from nonmalignant growth. We report a case of large penile mass in an elderly male with a history of lichen sclerosis, highly suspicious for malignancy. Subsequent surgical removal and biopsy demonstrated pseudoepitheliomatous hyperplasia, an unusual benign histopathologic diagnosis with unclear prognosis. We review the literature and discuss options for treatment and surveillance. PMID:26793536

  7. Benign prostatic hyperplasia: A clinical review.

    PubMed

    Skinder, Danielle; Zacharia, Ilana; Studin, Jillian; Covino, Jean

    2016-08-01

    Benign prostatic hyperplasia (BPH) is an increasingly common diagnosis seen in men over age 50 years. Primary care providers must be aware of patient presentation, diagnostic tests, appropriate lifestyle modifications, treatment options, and potential complications in order to properly manage and educate patients with BPH. If left untreated, BPH can significantly decrease a man's quality of life; however, many pharmacologic and surgical treatments are available to control the symptoms. PMID:27367595

  8. Environmentally benign silicon solar cell manufacturing

    SciTech Connect

    Tsuo, Y.S.; Gee, J.M.; Menna, P.; Strebkov, D.S.; Pinov, A.; Zadde, V.

    1998-09-01

    The manufacturing of silicon devices--from polysilicon production, crystal growth, ingot slicing, wafer cleaning, device processing, to encapsulation--requires many steps that are energy intensive and use large amounts of water and toxic chemicals. In the past two years, the silicon integrated-circuit (IC) industry has initiated several programs to promote environmentally benign manufacturing, i.e., manufacturing practices that recover, recycle, and reuse materials resources with a minimal consumption of energy. Crystalline-silicon solar photovoltaic (PV) modules, which accounted for 87% of the worldwide module shipments in 1997, are large-area devices with many manufacturing steps similar to those used in the IC industry. Obviously, there are significant opportunities for the PV industry to implement more environmentally benign manufacturing approaches. Such approaches often have the potential for significant cost reduction by reducing energy use and/or the purchase volume of new chemicals and by cutting the amount of used chemicals that must be discarded. This paper will review recent accomplishments of the IC industry initiatives and discuss new processes for environmentally benign silicon solar-cell manufacturing.

  9. Production of levulinic acid, furfural, and gamma valerolactone from C.sub.5 and C.sub.6 carbohydrates in mono- and biphasic systems using gamma-valerolactone as a solvent

    DOEpatents

    Dumesic, James A.; Alonso, David Martin; Gurbuz, Elif I.; Wettstein, Stephanie G.

    2013-03-19

    A method to make levulinic acid (LA), furfural, or gamma-valerolactone (GVL). React cellulose (and/or other C.sub.6 carbohydrates) or xylose (and/or other C.sub.5 carbohydrates) or combinations thereof in a monophasic reaction medium comprising GVL and an acid; or (ii) a biphasic reaction system comprising an organic layer comprising GVL, and a substantially immiscible aqueous layer. At least a portion of the cellulose (and/or other C.sub.6 carbohydrates), if present, is converted to LA and at least a portion of the xylose (and/or other C.sub.5 carbohydrates), if present, is converted into furfural.

  10. Experimental validation of a new biphasic model of the contact mechanics of the porcine hip

    PubMed Central

    Wang, Qianqian; Jin, Zhongmin; Williams, Sophie; Fisher, John; Wilcox, Ruth K

    2014-01-01

    Hip models that incorporate the biphasic behaviour of articular cartilage can improve understanding of the joint function, pathology of joint degeneration and effect of potential interventions. The aim of this study was to develop a specimen-specific biphasic finite element model of a porcine acetabulum incorporating a biphasic representation of the articular cartilage and to validate the model predictions against direct experimental measurements of the contact area in the same specimen. Additionally, the effect of using a different tension–compression behaviour for the solid phase of the articular cartilage was investigated. The model represented different radial clearances and load magnitudes. The comparison of the finite element predictions and the experimental measurement showed good agreement in the location, size and shape of the contact area, and a similar trend in the relationship between contact area and load was observed. There was, however, a deviation of over 30% in the magnitude of the contact area, which might be due to experimental limitations or to simplifications in the material constitutive relationships used. In comparison with the isotropic solid phase model, the tension–compression solid phase model had better agreement with the experimental observations. The findings provide some confidence that the new biphasic methodology for modelling the cartilage is able to predict the contact mechanics of the hip joint. The validation provides a foundation for future subject-specific studies of the human hip using a biphasic cartilage model. PMID:24878736

  11. Monophasic and Biphasic Electrical Stimulation Induces a Precardiac Differentiation in Progenitor Cells Isolated from Human Heart

    PubMed Central

    Pietronave, Stefano; Zamperone, Andrea; Oltolina, Francesca; Colangelo, Donato; Follenzi, Antonia; Novelli, Eugenio; Diena, Marco; Pavesi, Andrea; Consolo, Filippo; Fiore, Gianfranco Beniamino; Soncini, Monica

    2014-01-01

    Electrical stimulation (ES) of cells has been shown to induce a variety of responses, such as cytoskeleton rearrangements, migration, proliferation, and differentiation. In this study, we have investigated whether monophasic and biphasic pulsed ES could exert any effect on the proliferation and differentiation of human cardiac progenitor cells (hCPCs) isolated from human heart fragments. Cells were cultured under continuous exposure to monophasic or biphasic ES with fixed cycles for 1 or 3 days. Results indicate that neither stimulation protocol affected cell viability, while the cell shape became more elongated and reoriented more perpendicular to the electric field direction. Moreover, the biphasic ES clearly induced the upregulation of early cardiac transcription factors, MEF2D, GATA-4, and Nkx2.5, as well as the de novo expression of the late cardiac sarcomeric proteins, troponin T, cardiac alpha actinin, and SERCA 2a. Both treatments increased the expression of connexin 43 and its relocation to the cell membrane, but biphasic ES was faster and more effective. Finally, when hCPCs were exposed to both monophasic and biphasic ES, they expressed de novo the mRNA of the voltage-dependent calcium channel Cav 3.1(α1G) subunit, which is peculiar of the developing heart. Taken together, these results show that ES alone is able to set the conditions for early differentiation of adult hCPCs toward a cardiac phenotype. PMID:24328510

  12. Percutaneous biphasic electrical stimulation for treatment of obstructive sleep apnea syndrome.

    PubMed

    Hu, Lianggang; Xu, Xiaomei; Gong, Yongsheng; Fan, Xiaofang; Wang, Liangxing; Zhang, Jianhua; Zeng, Yanjun

    2008-01-01

    In this paper, we study the effect of stimulation of the genioglossus with percutaneous biphasic electrical pulses on patients with the obstructive sleep apnea syndrome (OSAS). The experiment was conducted in 22 patients clinically diagnosed with OSAS. The patients were monitored with polysomnography (PSG) in the trial. When the sleep apnea was detected, the genioglossus was stimulated with percutaneous biphasic electrical pulses that were automatically regulated by a microcontroller to achieve the optimal effect. The percutaneous biphasic electrical stimulation caused contraction of the genioglossus, forward movement of the tongue, and relieving of the glossopharyngeal airway obstruction. The SaO2, apnea time, hypoxemia time, and change of respiratory disturbance index (RDI) were compared in patients with treatment and without treatment. With percutaneous biphasic electrical stimulation of the genioglossus, the OSAS patients showed apnea time decreased (P < 0.01), RDI decreased (P < 0.01), and SaO2 increased (P < 0.01). No tissue injury or major discomfort was noticed during the trial. The stimulation of genioglossus with percutaneous biphasic electrical current pulse is an effective method for treating OSAS. PMID:18232360

  13. Osteoblastic cell response on biphasic fluorhydroxyapatite/strontium-substituted hydroxyapatite coatings.

    PubMed

    Yin, Ping; Feng, Fang Fang; Lei, Ting; Zhong, Xiao Huan; Jian, Xin Chun

    2014-03-01

    Fluorhydroxyapatite/strontium-substituted hydroxyapatite (FHA/SrHA) biphasic coatings with F and Sr elements incorporated simultaneously into one coating layer were prepared on titanium substrate via colloidal sol-gel method. The bioactivity of the as-prepared FHA/SrHA biphasic coatings was evaluated in vitro by immersion in simulated body fluid (SBF). All the biphasic coatings exhibited great ability to induce apatite precipitation on their surfaces. In vitro cell responses were evaluated using osteoblast-like MG63 cells in terms of cell proliferation and differentiation (alkaline phosphatase activity and osteocalcin level). The biphasic coatings show significantly positive effects on the viability and functional activity of osteoblastic cells with clear evidence that an optimum SrHA amount dose exists, indicating that the coexistence of FHA and SrHA had a synergistic stimulatory effect. This finding suggests the potential use of this colloidal sol-gel derived FHA/SrHA biphasic coatings for hard tissue applications. PMID:23533202

  14. EQUIVALENCE BETWEEN SHORT-TIME BIPHASIC AND INCOMPRESSIBLE ELASTIC MATERIAL RESPONSES

    PubMed Central

    Ateshian, Gerard A.; Ellis, Benjamin J.; Weiss, Jeffrey A.

    2009-01-01

    Porous-permeable tissues have often been modeled using porous media theories such as the biphasic theory. This study examines the equivalence of the short-time biphasic and incompressible elastic responses for arbitrary deformations and constitutive relations from first principles. This equivalence is illustrated in problems of unconfined compression of a disk, and of articular contact under finite deformation, using two different constitutive relations for the solid matrix of cartilage, one of which accounts for the large disparity observed between the tensile and compressive moduli in this tissue. Demonstrating this equivalence under general conditions provides a rationale for using available finite element codes for incompressible elastic materials as a practical substitute for biphasic analyses, so long as only the short-time biphasic response is sought. In practice, an incompressible elastic analysis is representative of a biphasic analysis over the short-term response δt≪Δ2/‖C4‖||K||, where Δ is a characteristic dimension, C4 is the elasticity tensor and K is the hydraulic permeability tensor of the solid matrix. Certain notes of caution are provided with regard to implementation issues, particularly when finite element formulations of incompressible elasticity employ an uncoupled strain energy function consisting of additive deviatoric and volumetric components. PMID:17536908

  15. Anaphylaxis presentations to an emergency department in Hong Kong: incidence and predictors of biphasic reactions.

    PubMed

    Smit, De Villiers; Cameron, Peter A; Rainer, Timothy H

    2005-05-01

    We describe the epidemiology, clinical features and management of anaphylaxis in a population in Hong Kong, including the features associated with progression to biphasic reactions and the nature of these reactions. A retrospective review was undertaken of patients of all age groups, presenting consecutively to the resuscitation room of a large Hong Kong emergency department with the diagnosis of anaphylaxis, from March 1999 to February 2003. There were 282 patients included. Median age was 28 years, with 59% male. A precipitant was identified in 89%, with 19% of patients claiming a known allergy to the precipitant. Seafood was responsible for 71% of all food-related reactions. More patients reacted to nonsteroidal anti-inflammatory drugs rather than antibiotics. Cutaneous features were present in 79%, and 12% presented with hypotension. Ninety-five percent received H1 antagonist, and 67% received epinephrine. Biphasic reactions were reported in 15 (5.3%) cases with 20% of these patients having unstable vital signs. The mean time from treatment to onset of biphasic reaction was 8 h (range 1-23). Patients with respiratory features on initial presentation were less likely to develop biphasic reactions. It is concluded that prolonged observation of patients with anaphylaxis is important, because of the risk of biphasic reactions. Better education could prevent recurrent anaphylaxis. PMID:15837017

  16. Probing the limit of magnesium uptake by β-tricalcium phosphate in biphasic mixtures formed from calcium deficient apatites

    NASA Astrophysics Data System (ADS)

    Kumar, P. Nandha; Mishra, Sandeep K.; Kannan, S.

    2015-11-01

    A series of magnesium doped non-stoichiometric calcium deficient apatites were synthesized through an aqueous precipitation route. The resultant structural changes during heat treatment were investigated by X-ray diffraction, Raman and FT-IR spectroscopy and Rietveld refinement. The results confirmed the formation of biphasic mixtures comprising Ca10(PO4)6(OH)2 and β-Ca3(PO4)2 after heat treatment at 1000 °C with the preferential occupancy of Mg2+ at the crystal lattice of β-Ca3(PO4)2. The concentration of Mg2+ uptake in β-Ca3(PO4)2 is limited till reaching the stoichiometric ratio of (Ca+Mg)/P=1.67 and beyond this stoichiometric value [(Ca+Mg)/P>1.67], Mg2+ precipitates as Mg(OH)2 and thereafter gets converted to MgO during heat treatment. Any kind of Mg2+ uptake in the crystal lattice of Ca10(PO4)6(OH)2 is discarded from the investigation.

  17. A finite element implementation for biphasic contact of hydrated porous media under finite deformation and sliding

    PubMed Central

    Guo, Hongqiang; Shah, Mitul; Spilker, Robert L.

    2014-01-01

    The study of biphasic soft tissues contact is fundamental to understanding the biomechanical behavior of human diarthrodial joints. However, to date, few biphasic finite element contact analysis for 3D physiological geometries under finite deformation has been developed. The objective of this paper is to develop a hyperelastic biphasic contact implementation for finite deformation and sliding problem. An augmented Lagrangian method was used to enforce the continuity of contact traction and fluid pressure across the contact interface. The finite element implementation was based on a general purpose software, COMSOL Multiphysics. The accuracy of the implementation is verified using example problems, for which solutions are available by alternative analyses. The implementation was proven to be robust and able to handle finite deformation and sliding. PMID:24496915

  18. Investigation of the feasibility of a biphase turbine for industrial process energy recovery. Final report

    SciTech Connect

    Helgeson, N.

    1985-06-28

    Tests were conducted to assess the technical applicability of the Biphase turbine to two process streams. A Biphase impulse turbine was tested on a flashing Selexol stream used for removal of CO/sub 2/ from process gases. The experimental results showed that the two-phase nozzle performance of the flashing Selexol stream was substantially below equilibrium calculation predictions. Consequently, the turbine power generated by this expanding two-phase flow was below predicted values, and was approximately equivalent to the liquid hydraulic power available. Additional gas-liquid phase separation occurred on the rotor such that overall separation efficiency reached 98% of that which occurred in the long residence time settling tank (equilibrium). The Biphase reaction turbine was tested on a flashing natural gas/crude oil stream. Nozzle, rotary and overall turbine performance were in good agreement with pre-test predictions for power generation and efficiency of operation. 141 figs., 35 tabs.

  19. Three dimensional biphasic calcium phosphate nanocomposites for load bearing bioactive bone grafts.

    PubMed

    Garai, Subhadra; Sinha, Arvind

    2016-02-01

    Mimicking matrix mediated bio-mineralization process, three dimensional blocks of biphasic calcium phosphate (BCP, hydroxyapatite (HA) and β-tricalcium phosphate (TCP)) nanocomposites, having three different stoichiometries have been synthesized for possible application as load bearing synthetic bone graft or scaffolds. Biphasic blocks with three weight ratios of 20:80, 25:75 and 30:70 of HA and TCP respectively have been synthesized. Detailed structural and chemical characterization of the samples revealed a strong dependence of porosity and mechanical properties on the stoichiometry of biphasic blocks. Effect of physiological medium on the microstructure and mechanical properties of the three different blocks has also been studied. Bioactivity of the BCP block, exhibiting highest compressive strength in air as well as in physiological medium, has been evaluated through adhesion, proliferation and differentiation of mesenchymal stem cells using different markers. PMID:26652386

  20. Shock-induced termination of reentrant cardiac arrhythmias: Comparing monophasic and biphasic shock protocols

    SciTech Connect

    Bragard, Jean Simic, Ana; Elorza, Jorge; Grigoriev, Roman O.; Fenton, Flavio H.; Cherry, Elizabeth M.; Gilmour, Robert F.; Otani, Niels F.

    2013-12-15

    In this article, we compare quantitatively the efficiency of three different protocols commonly used in commercial defibrillators. These are based on monophasic and both symmetric and asymmetric biphasic shocks. A numerical one–dimensional model of cardiac tissue using the bidomain formulation is used in order to test the different protocols. In particular, we performed a total of 4.8 × 10{sup 6} simulations by varying shock waveform, shock energy, initial conditions, and heterogeneity in internal electrical conductivity. Whenever the shock successfully removed the reentrant dynamics in the tissue, we classified the mechanism. The analysis of the numerical data shows that biphasic shocks are significantly more efficient (by about 25%) than the corresponding monophasic ones. We determine that the increase in efficiency of the biphasic shocks can be explained by the higher proportion of newly excited tissue through the mechanism of direct activation.

  1. A transversely isotropic biphasic model for unconfined compression of growth plate and chondroepiphysis.

    PubMed

    Cohen, B; Lai, W M; Mow, V C

    1998-08-01

    Using the biphasic theory for hydrated soft tissues (Mow et al., 1980) and a transversely isotropic elastic model for the solid matrix, an analytical solution is presented for the unconfined compression of cylindrical disks of growth plate tissues compressed between two rigid platens with a frictionless interface. The axisymmetric case where the plane of transverse isotropy is perpendicular to the cylindrical axis is studied, and the stress-relaxation response to imposed step and ramp displacements is solved. This solution is then used to analyze experimental data from unconfined compression stress-relaxation tests performed on specimens from bovine distal ulnar growth plate and chondroepiphysis to determine the biphasic material parameters. The transversely isotropic biphasic model provides an excellent agreement between theory and experimental results, better than was previously achieved with an isotropic model, and can explain the observed experimental behavior in unconfined compression of these tissues. PMID:10412420

  2. Shock-induced termination of reentrant cardiac arrhythmias: Comparing monophasic and biphasic shock protocols

    NASA Astrophysics Data System (ADS)

    Bragard, Jean; Simic, Ana; Elorza, Jorge; Grigoriev, Roman O.; Cherry, Elizabeth M.; Gilmour, Robert F.; Otani, Niels F.; Fenton, Flavio H.

    2013-12-01

    In this article, we compare quantitatively the efficiency of three different protocols commonly used in commercial defibrillators. These are based on monophasic and both symmetric and asymmetric biphasic shocks. A numerical one-dimensional model of cardiac tissue using the bidomain formulation is used in order to test the different protocols. In particular, we performed a total of 4.8 × 106 simulations by varying shock waveform, shock energy, initial conditions, and heterogeneity in internal electrical conductivity. Whenever the shock successfully removed the reentrant dynamics in the tissue, we classified the mechanism. The analysis of the numerical data shows that biphasic shocks are significantly more efficient (by about 25%) than the corresponding monophasic ones. We determine that the increase in efficiency of the biphasic shocks can be explained by the higher proportion of newly excited tissue through the mechanism of direct activation.

  3. Citrate-Based Biphasic Scaffolds for the Repair of Large Segmental Bone Defects

    PubMed Central

    Guo, Ying; Tran, Richard T.; Xie, Denghui; Nguyen, Dianna Y.; Gerhard, Ethan; Guo, Jinshan; Wang, Yuchen; Tang, Jiajun; Zhang, Zhongming; Bai, Xiaochun; Yang, Jian

    2014-01-01

    Attempts to replicate native tissue architecture have lead to the design of biomimetic scaffolds focused on improving functionality. In this study, biomimetic citrate-based poly (octanediol citrate) – click hydroxyapatite (POC-Click-HA) scaffolds were developed to simultaneously replicate the compositional and architectural properties of native bone tissue while providing immediate structural support for large segmental defects following implantation. Biphasic scaffolds were fabricated with 70% internal phase porosity and various external phase porosities (between 5–50%) to mimic the bimodal distribution of cancellous and cortical bone, respectively. Biphasic POC-Click-HA scaffolds displayed compressive strengths up to 37.45 ± 3.83 MPa, which could be controlled through the external phase porosity. The biphasic scaffolds were also evaluated in vivo for the repair of 10-mm long segmental radial defects in rabbits and compared to scaffolds of uniform porosity as well as autologous bone grafts after 5, 10, and 15 weeks of implantation. The results showed that all POC-Click-HA scaffolds exhibited good biocompatibility and extensive osteointegration with host bone tissue. Biphasic scaffolds significantly enhanced new bone formation with higher bone densities in the initial stages after implantation. Biomechanical and histomorphometric analysis supported a similar outcome with biphasic scaffolds providing increased compression strength, interfacial bone ingrowth, and periosteal remodeling in early time points, but were comparable to all experimental groups after 15 weeks. These results confirm the ability of biphasic scaffold architectures to restore bone tissue and physiological functions in the early stages of recovery, and the potential of citrate-based biomaterials in orthopedic applications. PMID:24829094

  4. A Structurally and Functionally Biomimetic Biphasic Scaffold for Intervertebral Disc Tissue Engineering

    PubMed Central

    Choy, Andrew Tsz Hang; Chan, Barbara Pui

    2015-01-01

    Tissue engineering offers high hopes for the treatment of intervertebral disc (IVD) degeneration. Whereas scaffolds of the disc nucleus and annulus have been extensively studied, a truly biomimetic and mechanically functional biphasic scaffold using naturally occurring extracellular matrix is yet to be developed. Here, a biphasic scaffold was fabricated with collagen and glycosaminoglycans (GAGs), two of the most abundant extracellular matrix components in the IVD. Following fabrication, the scaffold was characterized and benchmarked against native disc. The biphasic scaffold was composed of a collagen-GAG co-precipitate making up the nucleus pulposus-like core, and this was encapsulated in multiple lamellae of photochemically crosslinked collagen membranes comprising the annulus fibrosus-like lamellae. On mechanical testing, the height of our engineered disc recovered by ~82-89% in an annulus-independent manner, when compared with the 99% recovery exhibited by native disc. The annulus-independent nature of disc height recovery suggests that the fluid replacement function of the engineered nucleus pulposus core might mimic this hitherto unique feature of native disc. Biphasic scaffolds comprised of 10 annulus fibrosus-like lamellae had the best overall mechanical performance among the various designs owing to their similarity to native disc in most aspects, including elastic compliance during creep and recovery, and viscous compliance during recovery. However, the dynamic mechanical performance (including dynamic stiffness and damping factor) of all the biphasic scaffolds was similar to that of the native discs. This study contributes to the rationalized design and development of a biomimetic and mechanically viable biphasic scaffold for IVD tissue engineering. PMID:26115332

  5. Endoscopic management of benign biliary strictures

    PubMed Central

    Visrodia, Kavel H; Tabibian, James H; Baron, Todd H

    2015-01-01

    Endoscopic management of biliary obstruction has evolved tremendously since the introduction of flexible fiberoptic endoscopes over 50 years ago. For the last several decades, endoscopic retrograde cholangiopancreatography (ERCP) has become established as the mainstay for definitively diagnosing and relieving biliary obstruction. In addition, and more recently, endoscopic ultrasonography (EUS) has gained increasing favor as an auxiliary diagnostic and therapeutic modality in facilitating decompression of the biliary tree. Here, we provide a review of the current and continually evolving role of gastrointestinal endoscopy, including both ERCP and EUS, in the management of biliary obstruction with a focus on benign biliary strictures. PMID:26322153

  6. Clarithromycin Culprit of Benign Intracranial Hypertension

    PubMed Central

    Khan, Habib Rehman; Mason, Colin; Mulcahy, Riona

    2015-01-01

    Benign intracranial hypertension is characterized with increase in CSF opening pressure with no specific etiology. It is predominantly found in women of child bearing age and particularly in individuals with obesity. Visual disturbances or loss and associated headaches are common and can lead to blindness if left untreated. Diagnosis can be achieved once other causes of visual loss, headaches and high opening pressures are excluded. Management consists of serial optic disc assessments although no specific treatment is available despite recent trials using carbonic anhydrase inhibitors. Diet modification and weight management can help in therapy. PMID:26713029

  7. OTC tamsulosin for benign prostatic hyperplasia.

    PubMed

    2010-10-01

    Earlier this year, tamsulosin, an alpha blocker previously only available on prescription, became available for sale by pharmacists as a treatment for functional symptoms of benign prostatic hyperplasia (BPH) in men aged 45-75 years (Flomax Relief MR - Boehringer Ingelheim). A television advert for the over-the-counter (OTC) product claims that it is a "simple and effective" treatment that can relieve symptoms within 1 week, allowing the user to "take control of your annoying pee problems".¹ Here we review the evidence on tamsulosin and assess whether its availability as an OTC product confers worthwhile advantages. PMID:20926447

  8. Thallium-201 uptake in a benign thymoma

    SciTech Connect

    Campeau, R.J.; Ey, E.H.; Varma, D.G.

    1986-07-01

    A 68-year-old woman was admitted with atypical angina. A chest radiograph showed an anterior mediastinal mass that was confirmed on CT. The mass was relatively avascular and separate from the heart and great vessels. She underwent stress thallium testing that demonstrated no exercise-induced ischemia; however, an abnormal focus of thallium activity was present in the anterior mediastinum on stress and redistribution images. Cardiac catheterization demonstrated a normal left ventriculogram, coronary arteries and thoracic aorta. Subsequent surgery and pathologic examination revealed the mass to be a benign thymoma arising in the right lobe of the thymus gland.

  9. Models for studying benign prostatic hyperplasia.

    PubMed

    Mahapokai, W; Van Sluijs, F J; Schalken, J A

    2000-07-01

    Benign prostatic hyperplasia (BPH) is one of the most common diseases affecting aging man. Attempts have been made to clarify the etiology and pathogenesis and, to that end, experimental models have been developed. To date, in vitro and in vivo models have been used, depending on the concept of the study. Spontaneous animal models are limited to the chimpanzee and the dog. Ethical and financial factors restrict the applicability of these models. The hormonal-induced canine BPH model is a good alternative that closely resembles human BPH in many aspects. The experimental models currently used for studying BPH are reviewed. Prostate Cancer and Prostatic Diseases (2000) 3, 28-33 PMID:12497158

  10. Benign schwannoma of the maxillary antrum

    PubMed Central

    Hegde, Oshin; Desai, Dinkar; Bhandarkar, Gowri P.; Paul, Tony

    2016-01-01

    Schwannoma also known commonly as neurilemmoma and schwann cell tumor is a benign nerve sheath tumor. About 1/3rd cases of schwannoma arise from the head and neck region but rarely from the nasal and paranasal sinuses. The recurrence rate in these cases has reported to be very rare. We report a rare case of schwannoma in a 60-year-old woman arising from the maxillary sinus further eroding the orbital floor and nasal bone. We have also described the clinical presentation, radiological, histological findings, and management of the case. PMID:27095911

  11. Biphasic flow-volume loop in granulomatosis with polyangiitis related unilateral bronchus obstruction.

    PubMed

    Agrawal, Abhinav; Sahni, Sonu; Marder, Galina; Shah, Rakesh; Talwar, Arunabh

    2016-07-01

    Spirometry flow-volume measurement is used routinely in the outpatient setting to rule out obstructive lung diseases. Biphasic flow-volume loop is a classic presentation of unilateral bronchial stenosis due to multiple etiologies and it should raise clinical suspicion. Granulomatosis with polyangiitis (GPA) is a systemic inflammatory condition with pulmonary manifestations that may be infiltrative (e.g., pneumonia), hemorrhagic, and may rarely cause bronchial stenosis. Herein, we present a case of GPA-related, bronchial obstruction that caused biphasic flow-volume loop along with a literature review. PMID:27424828

  12. Biphasic decay of the Ca transient results from increased sarcoplasmic reticulum Ca leak

    PubMed Central

    Sankaranarayanan, Rajiv; Li, Yatong; Greensmith, David J.; Eisner, David A.

    2016-01-01

    Key points Ca leak from the sarcoplasmic reticulum through the ryanodine receptor (RyR) reduces the amplitude of the Ca transient and slows its rate of decay.In the presence of β‐adrenergic stimulation, RyR‐mediated Ca leak produces a biphasic decay of the Ca transient with a fast early phase and a slow late phase.Two forms of Ca leak have been studied, Ca‐sensitising (induced by caffeine) and non‐sensitising (induced by ryanodine) and both induce biphasic decay of the Ca transient.Only Ca‐sensitising leak can be reversed by traditional RyR inhibitors such as tetracaine.Ca leak can also induce Ca waves. At low levels of leak, waves occur. As leak is increased, first biphasic decay and then slowed monophasic decay is seen. The level of leak has major effects on the shape of the Ca transient. Abstract In heart failure, a reduction in Ca transient amplitude and contractile dysfunction can by caused by Ca leak through the sarcoplasmic reticulum (SR) Ca channel (ryanodine receptor, RyR) and/or decreased activity of the SR Ca ATPase (SERCA). We have characterised the effects of two forms of Ca leak (Ca‐sensitising and non‐sensitising) on calcium cycling and compared with those of SERCA inhibition. We measured [Ca2+]i with fluo‐3 in voltage‐clamped rat ventricular myocytes. Increasing SR leak with either caffeine (to sensitise the RyR to Ca activation) or ryanodine (non‐sensitising) had similar effects to SERCA inhibition: decreased systolic [Ca2+]i, increased diastolic [Ca2+]i and slowed decay. However, in the presence of isoproterenol, leak produced a biphasic decay of the Ca transient in the majority of cells while SERCA inhibition produced monophasic decay. Tetracaine reversed the effects of caffeine but not of ryanodine. When caffeine (1 mmol l−1) was added to a cell which displayed Ca waves, the wave frequency initially increased before waves disappeared and biphasic decay developed. Eventually (at higher caffeine concentrations), the

  13. Breast-feeding and benign breast disease.

    PubMed

    Bernardi, S; Londero, A P; Bertozzi, S; Driul, L; Marchesoni, D; Petri, R

    2012-01-01

    Benign breast disease (BBD) is very common among women in their fertile age, but its correlation with breast reproductive function remains unclear. Our study aimed to investigate the relation between BBD and breast-feeding. We collected data on 105 women with BBD and 98 controls, focusing on their reproductive history and breast-feeding. We analysed data by R (version 2.12.1) considering p < 0.05 as significant. The results showed that fibroadenoma represented the most frequent BBD (55%), followed by fibrocystic changes (19%), intraductal papilloma (6%) and inflammatory breast disorders (5%). The mean age was 31.5 years (± 6.1), BMI 21.2 kg/m² (± 3.4) and age at menarche 13.0 years (± 1.5). Duration of breast-feeding was not significantly different between controls and BBD types (p = NS). Selecting women with fibroadenoma breast-feeding duration directly correlated with the number of benign lesions (p < 0.05), which remains significant also by multivariate analysis. It was concluded that there seemed to be no difference in breast-feeding among BBDs types, but lactation may influence the number of fibroadenomas. Moreover, prospective studies would better define the correlation between lactation and BBDs. PMID:22185539

  14. Are deep eutectic solvents benign or toxic?

    PubMed

    Hayyan, Maan; Hashim, Mohd Ali; Hayyan, Adeeb; Al-Saadi, Mohammed A; AlNashef, Inas M; Mirghani, Mohamed E S; Saheed, Olorunnisola Kola

    2013-02-01

    In continuation of investigation for environmentally benign protocol for new solvents termed deep eutectic solvents (DESs), it is herein reported results concerning the toxicity and cytotoxicity of choline chloride (ChCl) based DESs with four hydrogen bond donors including glycerine, ethylene glycol, triethylene glycol and urea. The toxicity was investigated using two Gram positive bacteria Bacillus subtilis and Staphylococcus aureus, and two Gram negative bacteria Escherichia coli and Pseudomonas aeruginosa. The cytotoxicity effect was tested using the Artemia salina leach. It was found that there was no toxic effect for the tested DESs on all of the studied bacteria confirming their benign effects on these bacteria. Nevertheless, it was found that the cytotoxicity of DESs was much higher than their individual components (e.g. glycerine, ChCl) indicating that their toxicological behavior is different. For our best knowledge this is the first time that toxicity and cytotoxicity of DESs were studied. The toxicity and cytotoxicity of DESs varied depending on the structure of components. Careful usage of the terms non-toxicity and biodegradability must be considered. More investigation on this matter is required. PMID:23200570

  15. Histiocytic sarcoma that mimics benign histiocytosis.

    PubMed

    Boisseau-Garsaud, A M; Vergier, B; Beylot-Barry, M; Nastasel-Menini, F; Dubus, P; de Mascarel, A; Eghbali, H; Beylot, C

    1996-06-01

    A 28-year-old man presented with a histiocytic sarcoma of a very uncommon origin, as it had developed for several years like a benign cutaneous histiocytosis resembling generalized eruptive histiocytoma before becoming acute, with nodal and massive pulmonary involvement. Despite various chemotherapies, the patient died within 8 months. Skin biopsies showed histiocytic proliferation in the dermis and node biopsies showed histiocytic proliferation with a sinusoidal pattern. Immunohistochemical analysis, performed on paraffin-embedded sections, demonstrated strong labeling of tumoral cells for CD68 and moderate labeling for CD3 and CD4. CD30 labeling was negative. S-100 protein was positive on a Langerhans' cell reactive subpopulation. Electron microscopy confirmed the histiocytic nature of malignant cells and showed cytoplasmic inclusions such as regularly laminated bodies, dense bodies and pleomorphic inclusions. No Birbeck granules were seen. A gene rearrangement study of T-cell receptor gamma and immunoglobulin heavy chain genes showed a germline configuration. Histiocytic sarcoma is an extremely rare true histiocytic malignancy, the existence of which has been recently debated since it has often been mistaken in the past for large cell lymphomas. Such a deceptive onset as benign cutaneous histiocytosis has not been described in the literature to our knowledge. PMID:8793665

  16. Surface modification of porous polycaprolactone/biphasic calcium phosphate scaffolds for bone regeneration in rat calvaria defect.

    PubMed

    Kim, Ji-Hyun; Linh, Nguyen T B; Min, Young K; Lee, Byong-Taek

    2014-10-01

    In this study, polycaprolactone scaffolds fabricated by a salt-leaching process were loaded with biphasic calcium phosphate successfully to improve the osteoconductivity in bone regeneration. The surface of polycaprolactone/biphasic calcium phosphate scaffolds was aminolyzed by 1,6-hexamethylenediamine to introduce amino groups onto the surface, which was verified qualitatively by ninhyrin staining. Collagen was further immobilized on the aminolyzed porous polycaprolactone via N-ethyl-N'-(3-dimethylaminopropy) carbodiimide hydrochloride/hydroxy-2,5-dioxopyrolidine-3-sulfonic acid sodium cross-linking. The pore size of polycaprolactone/biphasic calcium phosphate-collagen scaffolds was 200-300 µm, which was suitable for bone in-growth. The X-ray photoelectron spectroscopy confirmed the coupling of collagen immobilized on the surface of polycaprolactone/biphasic calcium phosphate. In vitro results demonstrated that the spreading and viability of MC3T3-E1 cells were remarkably improved in the polycaprolactone/biphasic calcium phosphate-collagen scaffolds. The in vivo study was carried out by implanting the porous polycaprolactone, polycaprolactone/biphasic calcium phosphate, and polycaprolactone/biphasic calcium phosphate-collagen to the skulls of rats. Although the addition of biphasic calcium phosphate particles in the polycaprolactone scaffolds does not have a strong effect on the new bone formation, the immobilization of collagen on the polycaprolactone/biphasic calcium phosphate scaffolds significantly improved the bone regeneration even though the implantation time was short, 6 weeks. The present results provide more evidence that functionalizing polycaprolactone with biphasic calcium phosphate and collagen may be a feasible way to improve the osteoconduction in bone regeneration. PMID:24939961

  17. Primary adenocarcinoma of rete testis with distinct biphasic pattern: An extremely rare entity and diagnostic challenge.

    PubMed

    Ghosh, Prithwijit; Saha, Kaushik

    2015-01-01

    Primary adenocarcinoma of rete testis is one of the rarest intrascrotal tumors. Very few cases have been reported in the literature. In addition, presence of biphasic component creates difficulty in the diagnosis. We present here a unique third case of rete testis adenocarcinoma having distinct cytologically malignant spindle cell component in a young male who presented with recurrent hydrocele. PMID:25810664

  18. Intracellular lactate-mediated induction of estrogen receptor beta (ERβ) in biphasic malignant pleural mesothelioma cells

    PubMed Central

    Zonca, Sara; Cilli, Michele; Rinaldi, Maurizio; Daga, Antonio; Nilsson, Stefan; Moro, Laura

    2015-01-01

    Biphasic malignant pleural mesothelioma (MPM) is the second most common histotype of MPM. It is histologically characterized by the concomitant presence of epithelioid and sarcomatoid features, the latter associated with worse prognosis. In this report we describe that silencing of AKT1 in spindle-shaped biphasic MPM cells promotes the shift toward an epithelioid phenotype. Furthermore, AKT1 silencing resulted in decreased expression of the lactate/H+ symporter MCT4 and its chaperone CD147/Basigin, and in the induction of estrogen receptor β (ERβ) expression. We provide evidence that ERβ expression is induced by increased intracellular lactate concentration. Spheroid culturing and tumor growth of ERβ negative biphasic MPM in nude mice resulted in the induction of ERβ expression and response to the selective agonist KB9520. In both models, the treatment with the ERβ agonist results in reduced cell proliferation, decreased expression of MCT4 and CD147/Basigin and increased acetylation and inactivation of AKT1. Collectively, in response to metabolic changes, ERβ expression is induced and exerts an anti-tumor effect through selective agonist activation. The possibility to reverse the more aggressive biphasic mesothelioma histotype by targeting ERβ with a selective agonist could represent a new effective treatment strategy. PMID:26208479

  19. CHRONIC ALCOHOL CONSUMPTION HAS BIPHASIC EFFECTS ON HEPATIC INSULIN SIGNALING DEPENDENT ON DOSE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epidemiological studies have shown paradoxical biphasic effects of alcohol on health. Moderate drinkers have lower overall mortality than teetotalers or than heavy drinkers. There are protective effects of low levels of alcohol consumption (less than one drink day) on diabetes risk and other chroni...

  20. Biphasic Finite Element Contact Analysis of the Knee Joint using an Augmented Lagrangian Method

    PubMed Central

    Guo, Hongqiang; Maher, Suzanne A.; Spilker, Robert L.

    2013-01-01

    Biphasic contact analysis is essential to obtain a more complete understanding of soft tissue biomechanics; however, only a limited number of studies have addressed these types of problems. In this paper, a theoretically consistent biphasic finite element solution of the 2D axisymmetric human knee was developed, and an augmented Lagrangian method was used to enforce the biphasic continuity across the contact interface. The interaction between the fluid and solid matrices of the soft tissues of the knee joint, the stress and strain distributions within the meniscus, and the changes in stress and strain distributions in the articular cartilage of the femur and tibia after complete meniscectomy were investigated. It was found that (i) the fluid phase carries more than 60% of the load, which reinforces the need for the biphasic model for knee biomechanics; (ii) the inner third and outer two-thirds of the meniscus had different strain distributions; and (iii) the distributions of both maximum shear stress and maximum principal strain in articular cartilage changed after complete meniscectomy - with peak values increasing by over 350%. PMID:23498852

  1. Benign Duodenocolic Fistula: a Case Report.

    PubMed

    Soheili, Marzieh; Honarmand, Shirin; Soleimani, Heshmatollah; Elyasi, Anvar

    2015-08-01

    Benign duodenocolic fistula (DCF), known as a fistula between the duodenum and colon with or without cecum of nonmalignant origin, is an unusual complication of different gastrointestinal diseases. The present paper records a case in which the patient presented with chronic diarrhea, abdominal pain, weight loss as well as having a history of gastric ulcer. Most frequently the condition presents with signs of malabsorption such as weight loss and diarrhea, but other symptoms include nausea, vomiting (sometimes with fecal), and abdominal pain. Gastrointestinal inflammatory conditions are the usual causes. The most common ones are perforated duodenal ulcer and Crohn's disease. Barium enemas are usually diagnostic. Treatment consists of excising the fistula and repairing the duodenal and colonic defects. Closure of the fistula provides quick relief. PMID:26545997

  2. [Benign thyroid nodules: diagnostic and therapeutic approach].

    PubMed

    Durante, Cosimo; Cava, Francesco; Paciaroni, Alessandra; Filetti, Sebastiano

    2008-05-01

    In the last years an increase in thyroid nodules detection has been reported from several epidemiological studies. This trend is largely due to the routine use of diagnostic sonography procedures in clinical practice. Thyroid nodules, both palpable or not palpable, rarely turn out to be malignant. Fine-needle aspiration cytology (FNAc) plays a central role in establishing the nature of the nodule. Excluded the presence of malignant lesions, which are generally treated with surgery, physicians are faced with a variety of therapeutic options, and choosing the optimal approach can be a difficult task. These include a periodic follow-up alone without treatment, the iodine supplementation, the thyroid-hormone suppressive therapy, the radioiodine administration, the percutaneous ethanol injections, and the new technique of laser photocoagulation. In all cases, decisions on the management of benign thyroid nodules should always be based on clinical target and a careful analysis of benefits and risks to the patient. PMID:18581970

  3. Palladium-Catalyzed Environmentally Benign Acylation.

    PubMed

    Suchand, Basuli; Satyanarayana, Gedu

    2016-08-01

    Recent trends in research have gained an orientation toward developing efficient strategies using innocuous reagents. The earlier reported transition-metal-catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional-group-assisted ortho sp(2) C-H activation (i.e., ortho acylation) or carbonylation by activation of the carbonyl group (i.e., via the formation of enamines). Contradicting these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodoarenes with aldehydes without activation of the carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone. PMID:27377566

  4. [Neuroophthalmological aspects of benign intracranial hypertension].

    PubMed

    Eliseeva, N M; Serova, N K; Gasparian, S S; Shifrin, M A

    2008-01-01

    Benign intracranial hypertension (BICH) is characterized by elevated spinal fluid pressure in the absence of space-occupying lesion in the skull, dilated cerebral ventricles, significant neurological disorders, and altered spinal fluid composition. Forty-nine patients with a female predominance were examined. Their age ranged from 4 to 52 years (median 39 years). The most common predictors of BICH were overweight, endocrine disorders, and cerebral sinus thrombosis. Ophthalmoscopically, the patients were found to have early, moderate, and significant papilledema, and secondary optic atrophy. Examination of visual functions revealed these or those disturbances of visual acuity and/or field of vision in 43 of the 49 patients. The incidence and degree of visual disturbances depended on the stage of papilledema. Timely diagnosis and treatment in patients with BICH allows the development of visual disturbances to be prevented in them. PMID:18589651

  5. Benign Intracranial Hypertension: A Diagnostic Dilemma

    PubMed Central

    Shaw, Gary Y.; Million, Stephanie K.

    2012-01-01

    Benign intracranial hypertension (BIH) (also known as pseudotumor cerebri and empty sella syndrome) remains a diagnostic challenge to most physicians. The modified Dandy criteria consist of, the classic findings of headache, pulsatile tinnitus, papilledema, and elevated cerebrospinal fluid (CSF) pressure, however, these are rarely collectively present in any one patient. Furthermore, these findings can wax and wane over time. Due to the nature of this disease, both signs and symptoms may be intermittent, making definitive diagnosis difficult. Newer imaging studies, particularly the magnetic resonance venogram (MRV) along with a constellation of correlative findings and associated diseases have given new impetus in the diagnosis, treatment, and pathophysiology of this disease. This has led the authors to offer modifications to the classic Dandy criteria. This report presents three representative cases of BIH highlighting many of the newer advances in both diagnosis and treatment of this perplexing disorder. PMID:22928139

  6. Benign Vascular Malformation at the Ischial Tuberosity.

    PubMed

    Said, Rami; Bevelaqua, Anna-Christina

    2016-07-01

    A 31-year-old female student was referred to physical therapy with a chief complaint of proximal, posterior left thigh pain that began insidiously 12 months prior, and progressively worsened while training for a half-marathon. A mobile, soft mass was identified just inferior to the ischial tuberosity that was tender and painful to palpation, recreating the patient's chief complaint. Radiographic findings were negative for a suspected avulsion fracture at the ischial tuberosity. Therefore, the physician performed musculoskeletal ultrasonography, which revealed a superficial hypoechoic mass with vascular flow. Magnetic resonance imaging and a subsequent biopsy led to the diagnosis of a benign vascular malformation. J Orthop Sports Phys Ther 2016;46(7):607. doi:10.2519/jospt.2016.0410. PMID:27363574

  7. Endoscopic management of benign biliary strictures.

    PubMed

    Rustagi, Tarun; Jamidar, Priya A

    2015-01-01

    Benign biliary strictures are a common indication for endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic management has evolved over the last 2 decades as the current standard of care. The most common etiologies of strictures encountered are following surgery and those related to chronic pancreatitis. High-quality cross-sectional imaging provides a road map for endoscopic management. Currently, sequential placement of multiple plastic biliary stents represents the preferred approach. There is an increasing role for the treatment of these strictures using covered metal stents, but due to conflicting reports of efficacies as well as cost and complications, this approach should only be entertained following careful consideration. Optimal management of strictures is best achieved using a team approach with the surgeon and interventional radiologist playing an important role. PMID:25613176

  8. Clinical Evaluation of Benign Prostatic Hyperplasia

    PubMed Central

    McVary, Kevin T

    2003-01-01

    Benign prostatic hyperplasia (BPH) is the most common neoplastic condition afflicting men and constitutes a major factor impacting male health. Clinical evaluation to assess the presence and degree of voiding dysfunction and/or the role of BPH in its presence has an increasingly broad spectrum of treatment goals. The goals of the evaluation of such men are to identify the patient’s voiding or, more appropriately, urinary tract problems, both symptomatic and physiologic; to establish the etiologic role of BPH in these problems; to evaluate the necessity for and probability of success and risks of various therapeutic approaches; and to present the results of these assessments to the patient so he can make an informed decision about management recommendations and available alternatives. PMID:16985961

  9. Clinical Evaluation of Benign Prostatic Hyperplasia

    PubMed Central

    McVary, Kevin T

    2003-01-01

    Benign prostatic hyperplasia (BPH) is the most common neoplastic condition afflicting men and constitutes a major factor impacting male health. Clinical evaluation to assess the presence and degree of voiding dysfunction and/or the role of BPH in its presence has an increasingly broad spectrum of treatment goals. The goals of the evaluation of such men are to identify the patient’s voiding or, more appropriately, urinary tract problems, both symptomatic and physiologic; to establish the etiologic role of BPH in these problems; to evaluate the necessity for and probability of success and risks of various therapeutic approaches; and to present the results of these assessments to the patient so he can make an informed decision about management recommendations and available alternatives. PMID:16985968

  10. [Presumed benign ovarian tumors during pregnancy].

    PubMed

    Tariel, O; Huissoud, C; Rudigoz, R C; Dubernard, G

    2013-12-01

    The incidence of ovarian tumors diagnosed during pregnancy is between 0.3 and 5.4% (LE2). The most common ovarian tumors diagnosed during pregnancy are functional cysts diagnosed incidentally during the first trimester ultrasound (LE2) and spontaneous regression is often observed. Dermoid cysts and cystadenoma are the most frequent organic benign ovarian tumors diagnosed during pregnancy (LE2). The main complication of presumed benign ovarian tumor (PBOT) during pregnancy is adnexal torsion and is estimated at around 8% (LE2), especially at the end of the first trimester and during the second trimester (LE4). Tumor markers are not reliable during pregnancy to assess the risk of malignancy of ovarian tumor (LE2). Ultrasound remains the gold standard for characterizing an ovarian tumor during pregnancy (LE3), but with a lower specificity for the diagnosis of malignancy. Pelvic MRI is accurate in the diagnosis of ovarian tumors during pregnancy and brings additional information to ultrasound (LE4). Ultrasound-guided aspiration of ovarian tumors is not recommended during pregnancy (grade C). Expectation is recommended in cases of PBOT during pregnancy, which does not enlarge (grade C). Whatever the gestational age, surgery is recommended in patients with symptoms suggesting an adnexal torsion (grade C). Laparoscopy is possible during the first and second trimester of pregnancy for the management of symptomatic PBOT (LE3). The risk of miscarriage following surgery (laparoscopy and laparotomy) for ovarian tumor during pregnancy is estimated at 2.8% (LE3). The route of delivery should not be modified by the ovarian tumour, except in case of praevia cyst requiring a cesarean section, a complication or suspicion of malignancy (grade C). Surgical treatment of PBOT may be performed during a cesarean section indicated for another reason. The risk of torsion is increased during the postpartum period (LE4). PMID:24210242

  11. [Surgical therapy of benign thyroid gland diseases].

    PubMed

    Mann, B; Buhr, H J

    1998-01-01

    Operations due to benign thyroid diseases are one of the most common elective surgical procedures performed in Germany. In the majority of cases, the preoperative determination of the serum thyrotropin concentration and an ultrasound of the thyroid region are sufficient preoperative investigations. In cases of thyroid functional disorders a scintigram should be additionally performed. Indications for operation in nodular goiter are local, mechanical compression, suspicion of malignancy and focal or disseminated autonomy. In Graves' disease the indication for operation is usually recurrent hyperthyroidism after medical treatment. In endemic nodular goiter the morphology of the nodular thyroid tissue is the guideline for resection; i.e. all nodules have to be removed. In Graves' disease the function of the remaining thyroid tissue is essential. The standardized subtotal resection with remaining tissue around the hilus, which frequently barries nodules, should be avoided. Instead a selective resection which takes the individual morphology and function of the diseased thyroid tissue into account should be favorized. With this operative technique the surgeon will have frequently direct contact with the recurrent nerve and the parathyroids. It is documented, that intraoperative visualisation of the recurrent nerve decreases not only the rate of permanent nerve damages but increases as well the completeness of resection. Additionally, ligation of the inferior thyroid artery decreases the incidence of residual or recurrent disease without enlarging the risk of postoperative parathyroiprive hypocalcemia. An individual follow-up with iodine and/or thyroxine replacement therapy is an indispensable component of the surgical therapeutic approach. The target of thyroxine substitution in patients after resection due to benign thyroid diseases is a physiologic serum thyrotropin concentration (0.3 to 4.0 mU/l). PMID:9542021

  12. Environmentally benign processing of YAG transparent wafers

    NASA Astrophysics Data System (ADS)

    Yang, Yan; Wu, Yiquan

    2015-12-01

    Transparent yttrium aluminum garnet (YAG) wafers were successfully produced via aqueous tape casting and vacuum sintering techniques using a new environmentally friendly binder, a copolymer of isobutylene and maleic anhydride with the commercial name ISOBAM (noted as ISOBAM). Aqueous YAG slurries were mixed by ball-milling, which was followed by de-gassing and tape casting of wafers. The final YAG green tapes were homogenous and flexible, and could be bent freely without cracking. After the drying and sintering processes, transparent YAG wafers were achieved. The microstructures of both the green tape and vacuum-sintered YAG ceramic were observed by scanning electronic microscopy (SEM). Phase compositions were examined by X-ray diffraction (XRD). Optical transmittance was measured in UV-VIS regions with the result that the transmittance is 82.6% at a wavelength of 800 nm.

  13. [Treatment of benign laryngeal diseases using a CO2 laser].

    PubMed

    Betka, J; Klozar, J; Kasík, P; Taudy, M; Tichý, S

    1989-05-01

    CO2 laser surgery is becoming a part of larynx surgery. The authors inform about their experience in benign larynx tumours treatment. They present analysis of concrete therapeutic procedures in individual larynx affections. They conclude that laser surgery is an advantegous method for benign larynx tumours treatment. PMID:2772545

  14. Benign Biliary Strictures: Diagnostic Evaluation and Approaches to Percutaneous Treatment.

    PubMed

    Fidelman, Nicholas

    2015-12-01

    Interventional radiologists are often consulted to help identify and treat biliary strictures that can result from a variety of benign etiologies. Mainstays of noninvasive imaging for benign biliary strictures include ultrasound, contrast-enhanced computed tomography and magnetic resonance imaging, magnetic resonance cholangiopancreatography, and computed tomography cholangiography. Endoscopic retrograde cholangiography is the invasive diagnostic procedure of choice, allowing both localization of a stricture and treatment. Percutaneous biliary interventions are reserved for patients who are not candidates for endoscopic retrograde cholangiography (eg, history of distal gastrectomy and biliary-enteric anastomosis to a jejunal roux limb). This review discusses the roles of percutaneous transhepatic cholangiography and biliary drainage in the diagnosis of benign biliary strictures. The methodology for crossing benign biliary strictures, approaches to balloon dilation, management of recalcitrant strictures (ie, large-bore biliary catheters and retrievable covered stents), and the expected outcomes and complications of percutaneous treatment of benign biliary strictures are also addressed. PMID:26615161

  15. Synthesis of silver nanoparticles in textile finish aqueous system and their antimicrobial properties on cotton fibers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Silver nanoparticles (NPs) were synthesized by a simple and environmentally benign procedure using poly (ethylene glycol) (PEG) as reducing agent and stabilizer in the textile finish aqueous system, and their antimicrobial properties on greige (mechanically cleaned) and bleached cotton fibers were i...

  16. POLYSTYRENE SULFONIC ACID CATALYZED GREENER SYNTHESIS OF HYDRAZONES IN AQUEOUS MEDIUM USING MICROWAVES

    EPA Science Inventory

    An environmentally benign aqueous protocol for the synthesis of cyclic, bi-cyclic, and heterocyclic hydrazones using polystyrene sulfonic acid (PSSA) as a catalyst has been developed; the simple reaction proceeds efficiently in water in the absence of any organic solvent under mi...

  17. Ruthenium hydroxide supported on magnetic nanoparticles: a benign aqueous protocol for hydration of nitriles

    EPA Science Inventory

    Amides are an important class of compounds in the chemical and pharmaceutical industry1,2. Conventionally, amides have been synthesized by the hydration of nitriles, catalyzed by strong acids3 and bases4. Many by-products such as carboxylic acids are produced due to hydrolysis of...

  18. Benign paroxysmal tonic upgaze of childhood.

    PubMed

    Ouvrier, R A; Billson, F

    1988-07-01

    Four cases of an apparently benign ocular motor syndrome of childhood are reported. The features of the disorder are: (1) onset in early life; (2) periods of constant or variably sustained tonic conjugate upward deviation of the eyes; (3) down-beating saccades in attempted downgaze, which are difficult to sustain below the neutral positions; (4) apparently normal horizontal eye movements; (5) frequent relief by sleep; (6) otherwise normal neurological findings apart from mild ataxia, chronic in one boy and at times of illness in one of the other patients; (7) absence of deterioration during observation spanning up to 15 years; (8) eventual improvement but with some residual ocular movement problems in two cases; (9) normal metabolic, electroencephalographic, and neuroradiologic investigations; (10) normal brain examination findings in one patient who died accidentally; and (11) an apparently good response to levodopa therapy in one patient. To the authors' knowledge, this condition has not been described previously. It may be a new levodopa-responsive condition, secondary to a localized neurotransmitter deficiency. PMID:3209843

  19. Diode Laser Excision of Oral Benign Lesions

    PubMed Central

    Mathur, Ena; Sareen, Mohit; Dhaka, Payal; Baghla, Pallavi

    2015-01-01

    Introduction: Lasers have made tremendous progress in the field of dentistry and have turned out to be crucial in oral surgery as collateral approach for soft tissue surgery. This rapid progress can be attributed to the fact that lasers allow efficient execution of soft tissue procedures with excellent hemostasis and field visibility. When matched to scalpel, electrocautery or high frequency devices, lasers offer maximum postoperative patient comfort. Methods: Four patients agreed to undergo surgical removal of benign lesions of the oral cavity. 810 nm diode lasers were used in continuous wave mode for excisional biopsy. The specimens were sent for histopathological examination and patients were assessed on intraoperative and postoperative complications. Results: Diode laser surgery was rapid, bloodless and well accepted by patients and led to complete resolution of the lesions. The excised specimen proved adequate for histopathological examination. Hemostasis was achieved immediately after the procedure with minimal postoperative problems, discomfort and scarring. Conclusion: We conclude that diode lasers are rapidly becoming the standard of care in contemporary dental practice and can be employed in procedures requiring excisional biopsy of oral soft tissue lesions with minimal problems in histopathological diagnosis. PMID:26464781

  20. Benign disease of the common bile duct.

    PubMed

    Saxena, R; Pradeep, R; Chander, J; Kumar, P; Wig, J D; Yadav, R V; Kaushik, S P

    1988-08-01

    The incidence of common bile duct (CBD) pathology in a group of patients with benign biliary disease (n = 505) was found to be 23.2 per cent. The spectrum included 111 patients (90.2 per cent) with CBD stones, 37 of whom (33.3 per cent) had no symptoms or findings pre-operatively indicating CBD involvement. Five patients had papillary stenosis, three had postoperative CBD strictures, one had a choledochal cyst and one had an external biliary fistula. Of the 100 CBDs measuring more than 10 mm in diameter, 90 harboured calculi. In the remaining 23 CBDs measuring less than 10 mm, calculi were present in 21. The presence of CBD calculi was demonstrated by intra-operative cholangiography in 49 patients. In the remaining patients (n = 74), the diagnosis of CBD pathology was made either by percutaneous transhepatic cholangiography, endoscopic retrograde cholangio-pancreatography, T-tube cholangiography or peroperative palpation. The surgical procedures performed included choledochotomy and T-tube drainage (n = 74), transduodenal sphincteroplasty (n = 27) and choledochoduodenostomy (n = 18). The overall mortality and morbidity of CBD exploration was 3.3 per cent and 24.4 per cent respectively, which was significantly greater than that for cholecystectomy alone (0.3 per cent and 8.6 per cent respectively). Transduodenal sphincteroplasty carried a much higher mortality (11 per cent) and morbidity (52 per cent) when compared with other procedures. PMID:3167536

  1. [Pharmacological treatment of benign prostatic hyperplasia].

    PubMed

    Oelke, M; Martinelli, E

    2016-01-01

    The pharmacological treatment of benign prostatic hyperplasia (BPH) is indicated when men suffer from lower urinary tract symptoms (LUTS) but there are no absolute indications for prostate surgery or severe bladder outlet obstruction. Phytotherapy can be used in men with mild to moderate LUTS and alpha-blockers can quickly and effectively decrease the LUTS and symptomatic disease progression. Phosphodiesterase type 5 inhibitors (PDE5-I) are an alternative to alpha-blockers when men experience bothersome side effects from alpha-blockers or erectile dysfunction. If patients predominantly have bladder storage symptoms and a small prostate, muscarinic receptor antagonists are a viable treatment option. The combination of alpha-blocker plus muscarinic receptor antagonist is more efficacious in reducing LUTS than the single drugs alone. The 5 alpha-reductase inhibitors (5ARI) can significantly decrease LUTS and disease progression (e.g. acute urinary retention and need for prostate surgery) in men with larger prostates (> 30-40 ml). The combination of 5ARI plus alpha-blocker can reduce LUTS and disease progression more effectively than drug monotherapy. Combination therapy with PDE5-I (tadalafil) plus 5ARI (finasteride) reduces LUTS more substantially than 5ARI alone and, additionally, PDE5-Is reduce the sexual side effects during 5ARI treatment. PMID:26676726

  2. Benign and pathological electrocardiographic changes in athletes.

    PubMed

    Machado, Marino; Vaz Silva, Manuel

    2015-12-01

    Sudden cardiac death is the leading cause of death in athletes during sport. It is a tragic event that generates significant media attention and discussion throughout society as to whether everything possible had been done to prevent it. Regular physical exercise causes cardiac remodeling at both the mechanical and electrical level, known as athlete's heart, resulting in an electrocardiogram (ECG) considered abnormal compared with the ECGs of the general population. Some of these electrocardiographic changes are considered normal or physiological in athletes, while others suggest underlying cardiac disease with the potential to cause sudden cardiac death. There is thus an urgent need to define the electrocardiographic patterns that allow or prohibit participation in sports, and to differentiate them in terms of gender, ethnicity and age. The purpose of this review is to present the latest data on the electrocardiographic changes considered benign or pathological that are typically found in athletes and to critically analyze the most recent criteria for classifying ECGs in this population (the Seattle criteria), comparing them with previous guidelines and with the latest studies on the subject. This article also examines the question of including ECGs in pre-participation screening programs, the US and European approaches to the subject, and the most up-to-date data on the sensitivity, specificity and cost-effectiveness of the ECG in athletes. PMID:26643438

  3. Clinical Investigation of Benign Asbestos Pleural Effusion

    PubMed Central

    Fujimoto, Nobukazu; Gemba, Kenichi; Aoe, Keisuke; Kato, Katsuya; Yokoyama, Takako; Usami, Ikuji; Onishi, Kazuo; Mizuhashi, Keiichi; Yusa, Toshikazu; Kishimoto, Takumi

    2015-01-01

    There is no detailed information about benign asbestos pleural effusion (BAPE). The aim of the study was to clarify the clinical features of BAPE. The criteria of enrolled patients were as follows: (1) history of asbestos exposure; (2) presence of pleural effusion determined by chest X-ray, CT, and thoracentesis; and (3) the absence of other causes of effusion. Clinical information was retrospectively analysed and the radiological images were reviewed. There were 110 BAPE patients between 1991 and 2012. All were males and the median age at diagnosis was 74 years. The median duration of asbestos exposure and period of latency for disease onset of BAPE were 31 and 48 years, respectively. Mean values of hyaluronic acid, adenosine deaminase, and carcinoembryonic antigen in the pleural fluid were 39,840 ng/mL, 23.9 IU/L, and 1.8 ng/mL, respectively. Pleural plaques were detected in 98 cases (89.1%). Asbestosis was present in 6 (5.5%) cases, rounded atelectasis was detected in 41 (37.3%) cases, and diffuse pleural thickening (DPT) was detected in 30 (27.3%) cases. One case developed lung cancer (LC) before and after BAPE. None of the cases developed malignant pleural mesothelioma (MPM) during the follow-up. PMID:26689234

  4. [Minimally Invasive Treatment of Esophageal Benign Diseases].

    PubMed

    Inoue, Haruhiro

    2016-07-01

    As a minimally invasive treatment of esophageal achalasia per-oral endoscopic myotomy( POEM) was developed in 2008. More than 1,100 cases of achalasia-related diseases received POEM. Success rate of the procedure was more than 95%(Eckerdt score improvement 3 points and more). No serious( Clavian-Dindo classification III b and more) complication was experienced. These results suggest that POEM becomes a standard minimally invasive treatment for achalasia-related diseases. As an off-shoot of POEM submucosal tumor removal through submucosal tunnel (per-oral endoscopic tumor resection:POET) was developed and safely performed. Best indication of POET is less than 5 cm esophageal leiomyoma. A novel endoscopic treatment of gastroesophageal reflux disease (GERD) was developed. Anti-reflux mucosectomy( ARMS) is nearly circumferential mucosal reduction of gastric cardia mucosa. ARMS is performed in 56 consecutive cases of refractory GERD. No major complications were encountered and excellent clinical results. Best indication of ARMS is a refractory GERD without long sliding hernia. Longest follow-up case is more than 10 years. Minimally invasive treatments for esophageal benign diseases are currently performed by therapeutic endoscopy. PMID:27440038

  5. Skin conditions: benign nodular skin lesions.

    PubMed

    Nguyen, Tam; Zuniga, Ramiro

    2013-04-01

    Benign subcutaneous lesions are a common reason that patients visit family physicians. Lipomas are the most common of these lesions; they most often occur on the trunk and proximal extremities. Recent data show that as many as half of the fat cells in lipomas are atypical. Ultrasound is used increasingly to confirm lipoma diagnosis, but deep lesions should be evaluated with magnetic resonance imaging study or computed tomography scan to exclude involvement of underlying structures and/or liposarcoma. Small lesions can sometimes be managed with serial injections of midpotency steroids. Larger lesions (larger than 5 cm), those compressing other structures, or those suspicious for malignancy should be excised using standard surgical excision or, when possible, the newer minimal-scar segmental extraction technique. Ganglion cysts are another common lesion, the presence of which often is confirmed with ultrasound if the diagnosis is not clinically apparent. Management includes splinting, aspiration, and/or injection of steroids, with or without hyaluronidase. Epidermal inclusion cysts, also called sebaceous cysts, typically are asymptomatic unless they become infected. Ultrasound can aid in diagnosis. The only definitive management is surgical excision with complete removal of the cyst wall or capsule, using minimal-scar segmental extraction or conventional surgical removal. PMID:23600336

  6. Magnetic resonance imaging of benign prostatic hyperplasia

    PubMed Central

    Guneyli, Serkan; Ward, Emily; Thomas, Stephen; Yousuf, Ambereen Nehal; Trilisky, Igor; Peng, Yahui; Antic, Tatjana; Oto, Aytekin

    2016-01-01

    Benign prostatic hyperplasia (BPH) is a common condition in middle-aged and older men and negatively affects the quality of life. An ultrasound classification for BPH based on a previous pathologic classification was reported, and the types of BPH were classified according to different enlargement locations in the prostate. Afterwards, this classification was demonstrated using magnetic resonance imaging (MRI). The classification of BPH is important, as patients with different types of BPH can have different symptoms and treatment options. BPH types on MRI are as follows: type 0, an equal to or less than 25 cm3 prostate showing little or no zonal enlargements; type 1, bilateral transition zone (TZ) enlargement; type 2, retrourethral enlargement; type 3, bilateral TZ and retrourethral enlargement; type 4, pedunculated enlargement; type 5, pedunculated with bilateral TZ and/or retrourethral enlargement; type 6, subtrigonal or ectopic enlargement; type 7, other combinations of enlargements. We retrospectively evaluated MRI images of BPH patients who were histologically diagnosed and presented the different types of BPH on MRI. MRI, with its advantage of multiplanar imaging and superior soft tissue contrast resolution, can be used in BPH patients for differentiation of BPH from prostate cancer, estimation of zonal and entire prostatic volumes, determination of the stromal/glandular ratio, detection of the enlargement locations, and classification of BPH types which may be potentially helpful in choosing the optimal treatment. PMID:27015442

  7. Process for recovering pertechnetate ions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, Robin; Horwitz, E. Philip; Bond, Andrew H.

    1997-01-01

    A solid/liquid process for the separation and recovery of TcO.sub.4.sup.-1 ions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups; whereas the aqueous solution from which the TcO.sub.4.sup.-1 ions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt. A solid/liquid phase admixture of separation particles containing bound TcO.sub.4.sup.-1 ions in such an aqueous solution that is free from MoO.sub.4.sup.-2 ions is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture.

  8. Process for recovering pertechnetate ions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, R.; Horwitz, E.P.; Bond, A.H.

    1997-02-18

    A solid/liquid process for the separation and recovery of TcO{sub 4}{sup {minus}1} ions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups; whereas the aqueous solution from which the TcO{sub 4}{sup {minus}1} ions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt. A solid/liquid phase admixture of separation particles containing bound TcO{sub 4}{sup {minus}1} ions in such an aqueous solution that is free from MoO{sub 4}{sup {minus}2} ions is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture. 15 figs.

  9. PRRT2 mutation in Japanese children with benign infantile epilepsy.

    PubMed

    Okumura, Akihisa; Shimojima, Keiko; Kubota, Tetsuo; Abe, Shinpei; Yamashita, Shintaro; Imai, Katsumi; Okanishi, Tohru; Enoki, Hideo; Fukasawa, Tatsuya; Tanabe, Takuya; Dibbens, Leanne M; Shimizu, Toshiaki; Yamamoto, Toshiyuki

    2013-08-01

    Mutations in PRRT2 genes have been identified as a major cause of benign infantile epilepsy and/or paroxysmal kinesigenic dyskinesia. We explored mutations in PRRT2 in Japanese patients with BIE as well as its related conditions including convulsion with mild gastroenteritis and benign early infantile epilepsy. We explored PRRT2 mutations in Japanese children who had had unprovoked infantile seizures or convulsion with mild gastroenteritis. The probands included 16 children with benign infantile epilepsy, 6 children with convulsions with mild gastroenteritis, and 2 siblings with benign early infantile epilepsy. In addition, we recruited samples from family members when PRRT2 mutation was identified in the proband. Statistical analyses were performed to identify differences in probands with benign infantile epilepsy according to the presence or absence of PRRT2 mutation. Among a total of 24 probands, PRRT2 mutations was identified only in 6 probands with benign infantile epilepsy. A common insertion mutation, c.649_650insC, was found in 5 families and a novel missense mutation, c.981C>G (I327M), in one. The family history of paroxysmal kinesigenic dyskinesia was more common in probands with PRRT2 mutations than in those without mutations. Our study revealed that PRRT2 mutations are common in Japanese patients with benign infantile epilepsy, especially in patients with a family history of paroxysmal kinesigenic dyskinesia. PMID:23131349

  10. Microstructure Evolution of Biphasic TiNi1+x Sn Thermoelectric Materials

    NASA Astrophysics Data System (ADS)

    Verma, Nisha; Douglas, Jason E.; Krämer, Stephan; Pollock, Tresa M.; Seshadri, Ram; Levi, Carlos G.

    2016-05-01

    The effects of thermal treatment on the microstructure of biphasic materials comprising half-Heusler (hH) and full-Heusler (fH) phases, as well as on their associated thermal conductivity, are discussed. The focus of this study was on a biphasic hH/fH alloy of nominal stoichiometry TiNi1.2Sn, synthesized by containerless (magnetic levitation) induction melting. The alloy samples were exposed to various heat treatments to generate microstructures containing second-phase precipitates ranging in size from ~10 nm to a few micrometers. The materials were characterized with regard to morphology, size, shape, and orientation relationship of the fH and hH phases, both of which were present as precipitates within larger regions of the counterpart phase. The solidification path of the alloy and its implications for the subsequent microstructure evolution during heat treatment were elucidated, and relationships with the ensuing thermal conductivity were characterized.