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Sample records for albumin solutions implications

  1. [Pulsed radiolysis of aqueous solutions of serum albumin containing naphthoquinones].

    PubMed

    Pribush, A G; Savich, A V

    1987-01-01

    As was shown by the pulse radiolysis method the simultaneous presence of naphthoquinone and human serum albumin molecules in an aqueous solution leads to the adsorption of the former on the surface of the latter. It is suggested that in these conditions the protein tertiary structure changes. New conformation reduces the reactivity of albumin toward the hydrated electron. PMID:3628723

  2. The role of albumin receptors in regulation of albumin homeostasis: Implications for drug delivery.

    PubMed

    Bern, Malin; Sand, Kine Marita Knudsen; Nilsen, Jeannette; Sandlie, Inger; Andersen, Jan Terje

    2015-08-10

    Albumin is the most abundant protein in blood and acts as a molecular taxi for a plethora of small insoluble substances such as nutrients, hormones, metals and toxins. In addition, it binds a range of medical drugs. It has an unusually long serum half-life of almost 3weeks, and although the structure and function of albumin has been studied for decades, a biological explanation for the long half-life has been lacking. Now, recent research has unravelled that albumin-binding cellular receptors play key roles in the homeostatic regulation of albumin. Here, we review our current understanding of albumin homeostasis with a particular focus on the impact of the cellular receptors, namely the neonatal Fc receptor (FcRn) and the cubilin-megalin complex, and we discuss their importance on uses of albumin in drug delivery. PMID:26055641

  3. Corrosion behavior and surface characterization of titanium in solution containing fluoride and albumin.

    PubMed

    Takemoto, Shinji; Hattori, Masayuki; Yoshinari, Masao; Kawada, Eiji; Oda, Yutaka

    2005-03-01

    The objective of this study was to demonstrate the role of albumin on the corrosion behavior of titanium in a solution containing 2.0 g/l fluoride and either 0.1 or 1.0 g/l albumin. The corrosion behavior and surface characterization of passive films on titanium immersed in such a solution were examined. In addition, the change in pH and the concentration of dissolved titanium in the solution were examined. The results showed that the corrosion of titanium in a solution containing fluoride was distinct, and that adding albumin to the solution containing fluoride suppressed corrosion. Fluorine was detected on the titanium surface immersed in the solution containing fluoride, and dissolution of the titanium was confirmed. The titanium immersed in a solution containing both fluoride and albumin had an albumin film regardless of the albumin concentration. In addition, the amount of dissolved titanium from the titanium immersed in the solution was less than when the solution contained no albumin. It was suggested that the formation of adsorbed albumin films on or in the passive film acted to not only protect the titanium from attack by the fluoride but also suppressed dissolution of the titanium-fluoride compounds. PMID:15353194

  4. The influence of albumin on corrosion resistance of titanium in fluoride solution.

    PubMed

    Ide, Katsuhisa; Hattori, Masayuki; Yoshinari, Masao; Kawada, Eiji; Oda, Yutaka

    2003-09-01

    Proteins can interact with corrosion reactions in several ways. In this study, we investigated the effect of albumin on the corrosion resistance of titanium in the presence of fluoride. The effects of the NaF concentration, albumin concentration, and pH on the corrosion characteristics of commercially pure titanium (CP-Ti) were examined by means of electrochemical techniques. The corrosion resistance of titanium decreased as the NaF concentration increased and as pH decreased. The corrosion resistance of titanium in NaF solutions was improved in the presence of albumin. The natural electrode potential was elevated, and the passive current density was reduced by albumin at a concentration of 0.01%. The polarization resistance rose with increased concentrations of albumin in fluoride solution. These results showed that the albumin in saliva and dental plaque affected the corrosion resistance of CP-Ti in fluoride solution. PMID:14621001

  5. Influence of Millimeter Electromagnetic Waves on Fluorescence of Water-Saline Solutions of Human Serum Albumin

    NASA Astrophysics Data System (ADS)

    Vardevanyan, P. O.; Antonyan, A. P.; Shahinyan, M. A.; Mikaelyan, M. S.

    2016-07-01

    The effect of electromagnetic waves of the millimeter region on the conformation and fluorescence characteristics of human serum albumin was studied. It is shown that the irradiation of the albumin solution leads to an increase of the fluorescence intensity depending on the duration of irradiation. At an irradiation frequency of 48 GHz the fluorescence intensity of albumin hardly changes at all, while at 41.8 and 51.8 GHz it increases. It is also shown that when the irradiation frequency is 51.8 GHz, the intensity of the albumin solution fluorescence increases with increase of the irradiation time.

  6. Study of influence of millimeter range electromagnetic waves on water-saline solutions of albumin

    NASA Astrophysics Data System (ADS)

    Shahinyan, Mariam A.; Antonyan, Ara P.; Mikaelyan, Marieta S.; Vardevanyan, Poghos O.

    2015-01-01

    In this work, the effect of electromagnetic waves of millimeter diapason (EMW MM) on both melting parameters of serum albumin from human blood and its solution density has been studied. It was shown that the irradiation of albumin solution results in protein denaturation at higher temperatures than in the case of nonirradiated samples, which indicates the increase of albumin packing degree. It was also shown that the enhancement of albumin solution density takes place which indicates the protein packing degree change as well. The obtained data show that the effect of EMW MM does not depend on frequency of these waves, because alterations are revealed at all studied frequencies — 41.8, 48 and 51.8GHz.

  7. Glass transitions in aqueous solutions of protein (bovine serum albumin).

    PubMed

    Shinyashiki, Naoki; Yamamoto, Wataru; Yokoyama, Ayame; Yoshinari, Takeo; Yagihara, Shin; Kita, Rio; Ngai, K L; Capaccioli, Simone

    2009-10-29

    Measurements by adiabatic calorimetry of heat capacities and enthalpy relaxation rates of a 20% (w/w) aqueous solution of bovine serum albumin (BSA) by Kawai, Suzuki, and Oguni [Biophys. J. 2006, 90, 3732] have found several enthalpy relaxations at long times indicating different processes undergoing glass transitions. In a quenched sample, one enthalpy relaxation at around 110 K and another over a wide temperature range (120-190 K) were observed. In a sample annealed at 200-240 K after quenching, three separated enthalpy relaxations at 110, 135, and above 180 K were observed. Dynamics of processes probed by adiabatic calorimetric data are limited to long times on the order of 10(3) s. A fuller understanding of the processes can be gained by probing the dynamics over a wider time/frequency range. Toward this goal, we performed broadband dielectric measurements of BSA-water mixtures at various BSA concentrations over a wide frequency range of thirteen decades from 2 mHz to 1.8 GHz at temperatures from 80 to 270 K. Three relevant relaxation processes were detected. For relaxation times equal to 100 s, the three processes are centered approximately at 110, 135, and 200 K, in good agreement with those observed by adiabatic calorimetry. We have made the following interpretation of the molecular origins of the three processes. The fastest relaxation process having relaxation time of 100 or 1000 s at ca. 110 K is due to the secondary relaxation of uncrystallized water (UCW) in the hydration shell. The intermediate relaxation process with 100 s relaxation time at ca. 135 K is due to ice. The slowest relaxation process having relaxation time of 100 s at ca. 200 K is interpreted to originate from local chain conformation fluctuations of protein slaved by water. Experimental evidence supporting these interpretations include the change of temperature dependence of the relaxation time of the UCW at approximately T(gBSA) approximately = 200 K, the glass transition temperature of

  8. Serum albumin: touchstone or totem?

    PubMed

    Margarson, M P; Soni, N

    1998-08-01

    A decrease in serum albumin concentrations is an almost inevitable finding in disease states, and is primarily mediated in the acute phase by alterations in vascular permeability and redistribution. This change is not disease specific but marked changes that persist are generally associated with a poorer prognosis. Critical appraisal of long-standing practices and the availability of alternative colloid solutions have led to a reduction in albumin replacement therapy, and a widespread tolerance of lower albumin concentrations in patients. The factors determining serum albumin concentrations, their measurement and the implications of hypoalbuminaemia are reviewed. The clinical value of serum albumin measurement is discussed. PMID:9797524

  9. High-field NMR T 2 relaxation mechanism in D2O solutions of albumin

    NASA Astrophysics Data System (ADS)

    Yilmaz, A.; Zengin, B.

    2013-07-01

    400 MHz NMR T 2 in D2O solutions of albumin and pure D2O were measured at different temperatures. A relation, based on the chemical exchange between bound HDO and non-exchangeable protein protons, was derived theoretically for the contributions of bound HDO [ P b(1/ T 2b)]. A second relation was also derived theoretically by considering spin-rotation interactions between bound HDO and surrounding protein protons. The P b(1/ T 2b) values in albumin solutions were then determined by replacing experimental data into the first relation. The values of the 1/ T 2 and P b(1/ T 2b) in albumin solutions increase linearly with temperature( T), whereas the 1/ T 2 in D2O decreases with T. In addition, the spin-rotation correlation times were calculated from the second relation. The dipolar correlation time of albumin was then reproduced from the spin-rotation correlation times for confirmative purposes. In conclusion, the 1/ T 2 in albumin solutions with D2O is caused by spin-rotation interactions.

  10. Interaction of silicon nanoparticles with the molecules of bovine serum albumin in aqueous solutions

    SciTech Connect

    Anenkova, K A; Sergeeva, I A; Petrova, G P; Fedorova, K V; Osminkina, L A; Timoshenko, Viktor Yu

    2011-05-31

    Using the method of photon-correlation spectroscopy, the coefficient of translational diffusion D{sub t} and the hydrodynamic radius R of the particles in aqueous solutions of the bovine serum albumin, containing silicon nanoparticles, are determined. The character of the dependence of these parameters on the concentration of the protein indicates the absence of interaction between the studied particles in the chosen range of albumin concentrations 0.2 - 1.0 mg mL{sup -1}. (optical technologies in biophysics and medicine)

  11. Laser-induced preparation of volume nanocompositions in aqueous albumin solutions

    SciTech Connect

    Podgaetskii, V M; Simunin, M M; Savranskii, V V; Kononov, M A

    2007-09-30

    Ordered volume nanocompositions are obtained by exposing a colloidal aqueous solution of albumin with carbon nanotubes to cw IR laser radiation. Nanocompositions contain spherical and toroidal globules of size 100-500 nm with electric properties inherent in conglomerates of coiled nanotubes. The hardness of the material obtained depends on the irradiation intensity and time, and its consistence can be varied from pasty to glassy. (letters)

  12. Solution structure of RicC3, a 2S albumin storage protein from Ricinus communis.

    PubMed

    Pantoja-Uceda, David; Bruix, Marta; Giménez-Gallego, Guillermo; Rico, Manuel; Santoro, Jorge

    2003-12-01

    The three-dimensional structure in aqueous solution of recombinant (15)N labeled RicC3, a 2S albumin protein from the seeds of castor bean (Ricinus communis), has been determined by NMR methods. The computed structures were based on 1564 upper limit distance constraints derived from NOE cross-correlation intensities measured in the 2D-NOESY and 3D-HSQC-NOESY experiments, 70 phi torsion angle constraints obtained from (3)J(HNH)(alpha) couplings measured in the HNHA experiment, and 30 psi torsion angle constraints derived from (3)J(H)(alpha)(Ni+1) couplings measured in the HNHB experiment. The computed structures showed a RMSD radius of 0.64 A for the structural core. The resulting structure consists of five amphipatic helices arranged in a right-handed super helix, a folding motif first observed in nonspecific lipid transfer proteins. Different than the latter, RicC3 does have not an internal cavity, a fact that can be related to the exchange in the pairing of disulfide bridges in the segment.CXC. Previous attempts to determine high resolution structures of a 2S albumin protein by either X-ray crystallography or NMR methods failed because of the heterogeneity of the protein prepared from natural sources. Both 2S albumins and nonspecific lipid transfer proteins belong to the prolamine superfamily, some of whose members are food allergens. The solution structure for recombinant RicC3 determined here is a suitable representative structure for the broad family of seed 2S albumin proteins, which may help to establish meaningful relationships between structure and allergenicity. RicC3 is also the peptidic component of the immunomodulator Inmunoferon, a widely used pharmaceutical product, and its structure is expected to help understand its pharmaceutical activity. PMID:14636051

  13. Luminescent spectral characteristics of eosin in solutions of human serum albumin when denatured by treatment with sodium dodecyl sulfate

    NASA Astrophysics Data System (ADS)

    Vlasova, I. M.; Zemlyanskii, A. Yu.; Saletskii, A. M.

    2006-09-01

    From analysis of the fluorescence spectra of eosin molecules in a solution with human serum albumin (HSA), we have obtained information about the dynamics of protein conformational rearrangements during denaturing of the protein when treated with sodium dodecyl sulfate (SDS) for different pH values of the solution. We hypothesize that HSA denaturing in the presence of SDS occurs in two stages: the first stage is loosening of the protein globules, and the second stage is complete unfolding of the protein molecules. We have shown that denaturating of the protein in the presence of SDS passes through both stages for a solution pH below the isoelectric point of the albumin, while the denaturing stops in the first stage for a solution pH above the isoelectric point of the albumin.

  14. Comparison of Albumin, Hydroxyethyl Starch and Ringer Lactate Solution as Priming Fluid for Cardiopulmonary Bypass in Paediatric Cardiac Surgery

    PubMed Central

    Prajapati, Mrugesh; Solanki, Atul; Pandya, Himani

    2016-01-01

    Introduction In paediatric cardiac surgery, there is still not any information with regard to the best choice of priming fluids for Cardiopulmonary Bypass (CPB). Albumin, Hydroxyethyl Starch (HES) & ringer lactate are equally used, but each has its advantages & disadvantages. Albumin & HES had better fluid balance which affect outcome in paediatric cardiac surgery significantly. Aim To compare priming solution containing albumin, hydroxyethyl starch and ringer lactate during elective open-heart surgery in paediatrics aged up to 3 years. Materials and Methods All patients were managed by standardized institution protocol and were randomly distributed into three groups based on the priming solution which is used in the CPB Circuit and having 35 patients in each group. Group A: Receive albumin 10 ml/kg in priming solution, Group B: Receive Hydroxyethyl starch (HES130/0.4) 6% 20ml/kg in priming solution, Group C: Receive ringer lactate priming solution. Primary outcome variable included perioperative haemoglobin, total protein, colloid osmotic pressure, platelets, fluid balance, urine output, post-operative blood loss, blood products usage, renal & liver function, extubation time, ICU stay & outcome. Results Patients receiving albumin had higher perioperative platelet count, total protein level & colloid osmotic pressure, lesser post-operative blood loss & blood products requirement. Patients receiving HES had lower level of platelets postoperatively than ringer lactate group but not associated with increase blood loss. HES did not affect renal function & haemostasis in this dose. Patients receiving ringer lactate had positive fluid balance intraoperatively. All three groups have similar effect on renal & liver function, urine output, time to extubation, ICU stay & outcome. Conclusion We conclude that albumin is expensive but better prime as maintain haemostasis, colloid oncotic pressure & reduced blood product requirement. HES will not hamper haemostasis & renal

  15. DNP-Enhanced MAS NMR of Bovine Serum Albumin Sediments and Solutions

    PubMed Central

    2015-01-01

    Protein sedimentation sans cryoprotection is a new approach to magic angle spinning (MAS) and dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) spectroscopy of proteins. It increases the sensitivity of the experiments by a factor of ∼4.5 in comparison to the conventional DNP sample preparation and circumvents intense background signals from the cryoprotectant. In this paper, we investigate sedimented samples and concentrated frozen solutions of natural abundance bovine serum albumin (BSA) in the absence of a glycerol-based cryoprotectant. We observe DNP signal enhancements of ε ∼ 66 at 140 GHz in a BSA pellet sedimented from an aqueous solution containing the biradical polarizing agent TOTAPOL and compare this with samples prepared using the conventional protocol (i.e., dissolution of BSA in a glycerol/water cryoprotecting mixture). The dependence of DNP parameters on the radical concentration points to the presence of an interaction between TOTAPOL and BSA, so much so that a frozen solution sans cryoprotectant still gives ε ∼ 50. We have studied the interaction of BSA with another biradical, SPIROPOL, that is more rigid than TOTAPOL and has been reported to give higher enhancements. SPIROPOL was also found to interact with BSA, and to give ε ∼ 26 close to its maximum achievable concentration. Under the same conditions, TOTAPOL gives ε ∼ 31, suggesting a lesser affinity of BSA for SPIROPOL with respect to TOTAPOL. Altogether, these results demonstrate that DNP is feasible in self-cryoprotecting samples. PMID:24460530

  16. Study of the interaction of C60 fullerene with human serum albumin in aqueous solution

    SciTech Connect

    Li, Song; Zhao, Xiongce; Mo, Yiming; Cummings, Peter T; Heller, William T

    2013-01-01

    Concern about the toxicity of engineered nanoparticles, such as the prototypical nanomaterial C60 fullerene, continues to grow. While evidence continues to mount that C60 and its derivatives may pose health hazards, the specific molecular interactions of these particles with biological macromolecules require further investigation. To better understand the interaction of C60 with proteins, the protein human serum albumin (HSA) was studied in solution with C60 at C60:HSA molar ratios ranging from 1:2 to 4:1. HSA is the major protein component of blood plasma and plays a role in a variety of functions, such as the maintenance of blood pH and pressure. The C60-HSA interaction was probed by a combination of circular dichroism (CD) spectroscopy, small-angle neutron scattering (SANS) and atomistic molecular dynamics (MD) simulations to understand C60-driven changes in the structure of HSA in solution. The CD spectroscopy demonstrates that the secondary structure of the protein decreases in -helical content in response to the presence of C60. Similarly, C60 produces subtle changes in the solution conformation of HSA, as evidenced by the SANS data and MD. The data do not indicate that C60 is causing a change in the oligomerization state of the protein. Taken together results demonstrate that C60 interacts with HSA, but it does not strongly perturb the structure of the protein by unfolding it or inducing aggregation, suggesting a mechanism for transporting C60 throughout the body to accumulate in various tissues.

  17. Comparison of low molecular weight hydroxyethyl starch and human albumin as priming solutions in children undergoing cardiac surgery.

    PubMed

    Miao, Na; Yang, Jing; Du, Zhongtao; Liu, Wei; Ni, Hong; Xing, Jialin; Yang, Xiaofang; Xu, Bo; Hou, Xiaotong

    2014-09-01

    Human albumin is the conventional cardiopulmonary bypass circuit primer. However, it has high manufacturing costs. Crystalloid and colloid solutions have been developed as alternatives, including a new generation of non-ionic hydroxyethyl starch (HES). The efficacy of hydroxyethyl starch with a 130 molecular weight and substitution degree of 0.4 (hydroxyethyl starch 130/0.4) was compared with human albumin for use in cardiopulmonary bypass surgery in American Society of Anesthesiologists' grade I-II pediatric congenital heart disease patients. Efficacy was evaluated by comparing perioperative hemodynamic parameters, including plasma colloid osmotic pressure, renal function, blood loss, allogeneic blood volumes and plasma volume substitution. The hydroxyethyl starch group exhibited significantly higher preoperative colloid osmotic pressure (p<0.01) and significantly lower operative renal function and postoperative allogeneic blood volumes than the human albumin group. No significant differences were observed in serum creatinine, glucose, hematocrit or lactic acid levels (p>0.05). Our results indicate that hydroxyethyl starch may be a viable alternative to human albumin in pediatric patients undergoing relatively simple cardiopulmonary bypass surgeries. PMID:24658707

  18. Human albumin solution for patients with cirrhosis and acute on chronic liver failure: Beyond simple volume expansion.

    PubMed

    Valerio, Christopher; Theocharidou, Eleni; Davenport, Andrew; Agarwal, Banwari

    2016-03-01

    To provide an overview of the properties of human serum albumin (HSA), and to review the evidence for the use of human albumin solution (HAS) in critical illness, sepsis and cirrhosis. A MEDLINE search was performed using the terms "human albumin", "critical illness", "sepsis" and "cirrhosis". The references of retrieved articles were reviewed manually. Studies published between 1980 and 2014 were selected based on quality criteria. Data extraction was performed by all authors. HSA is the main plasma protein contributing greatly to its oncotic pressure. HSA demonstrates important binding properties for endogenous and exogenous toxins, drugs and drug metabolites that account for its anti-oxidant and anti-inflammatory properties. In disease states, hypoalbuminaemia is secondary to decreased HSA production, increased loss or transcapillary leakage into the interstitial space. HSA function can be also altered in disease with reduced albumin binding capacity and increased production of modified isoforms. HAS has been used as volume expander in critical illness, but received criticism due to cost and concerns regarding safety. More recent studies confirmed the safety of HAS, but failed to show any survival benefit compared to the cheaper crystalloid fluids, therefore limiting its use. On the contrary, in cirrhosis there is robust data to support the efficacy of HAS for the prevention of circulatory dysfunction post-large volume paracentesis and in the context of spontaneous bacterial peritonitis, and for the treatment of hepato-renal syndrome and hypervolaemic hyponatraemia. It is likely that not only the oncotic properties of HAS are beneficial in cirrhosis, but also its functional properties, as HAS replaces the dysfunctional HSA. The role of HAS as the resuscitation fluid of choice in critically ill patients with cirrhosis, beyond the established indications for HAS use, should be addressed in future studies. PMID:26981172

  19. Study of the dielectric function of aqueous solutions of glucose and albumin by THz time-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Nazarov, M. M.; Cherkasova, O. P.; Shkurinov, A. P.

    2016-06-01

    We report a study of aqueous solutions of glucose and bovine serum albumin using THz time-domain spectroscopy. To describe the permittivity of the solutions of these substances, we use a simplified model being applicable in the frequency range of 0.05 – 2.7 THz. On the assumption that most of the water molecules become bound at high concentrations of glucose and protein in the solution, the changes in water characteristics are investigated. To improve the reliability of the results, the measurements are performed by two independent methods: the method of attenuated total internal reflection and the transmission method. Combination of the results obtained by these two methods allows expanding the spectral range towards lower frequencies.

  20. Solution structure of a methionine-rich 2S albumin from sunflower seeds: relationship to its allergenic and emulsifying properties.

    PubMed

    Pantoja-Uceda, David; Shewry, Peter R; Bruix, Marta; Tatham, Arthur S; Santoro, Jorge; Rico, Manuel

    2004-06-01

    The three-dimensional structure in aqueous solution of SFA-8, a 2S albumin 103-residue protein from seeds of sunflower (Helianthus anuus L.), has been determined by NMR methods. An almost complete (1)H resonance assignment was accomplished from analysis of two-dimensional (2D) COSY and 2D TOCSY spectra, and the structure was computed by using restrained molecular dynamics on the basis of 1393 upper limit distance constraints derived from NOE cross-correlation intensities measured in 2D NOESY spectra. In contrast with most other 2S albumins, SFA-8 consists of a single polypeptide chain without any cleavage in the segment of residues 30-46. The computed structures exhibited an rmsd radius of 0.52 A for the backbone structural core (residues 11-30 and 46-101) and 1.01 A for the side chain heavy atoms. The resulting structure consists of five amphipathic helices arranged in a right-handed superhelix, a folding motif first observed in nonspecific lipid transfer (nsLTP) proteins, and common to other 2S albumins. In contrast to nsLTP proteins, neither SFA-8 nor RicC3 (a 2S albumin from castor bean) has an internal cavity that is able to host a lipid molecule, which results from an exchange in the pairing of disulfide bridges in the CXC segment. Both 2S albumins and nonspecific lipid transfer proteins belong to the prolamin superfamily, which includes a number of important food allergens. Differences in the extension and solvent exposition of the so-called "hypervariable loop" (which connects helices III and IV) in SFA-8 and RicC3 may be responsible for the different allergenic properties of the two proteins. SFA-8 has been shown to form highly stable emulsions with oil/water mixtures. We propose that these properties may be determined partly by a hydrophobic patch at the surface of the protein which consists of five methionines that partially hide the Trp76 residue. The flexibility of the loop which contains Trp76 and the hydrophobicity of the whole environment may favor

  1. The combination of mannitol and albumin in the priming solution reduces positive intraoperative fluid balance during cardiopulmonary bypass.

    PubMed

    Jenkins, I R; Curtis, A P

    1995-09-01

    During cardiopulmonary bypass (CPB) an adequate reservoir volume is maintained by the addition of crystalloid, colloid or packed cells to the reservoir. This volume contributes to the overall perioperative positive fluid balance. We studied the effect of the preoperative addition of either 75 g albumin, or 50 g mannitol followed by 50 g at commencement of rewarming or both of the above to a bypass circuit prime of lactated Ringer's solution (LR) on intraoperative fluid balance, postoperative indices of oxygenation and time to extubation. The study was a prospective, randomized, single-blinded controlled trial of 103 patients undergoing cardiac surgery requiring CPB. There was a large and highly significant reduction in volume of fluid added to the reservoir during CPB (2137 +/- 1499 ml versus 144 +/- 230 ml), the fluid balance during bypass, including prime volume (3236 +/- 650 ml versus 5876 +/- 1465 ml), and perioperative fluid balance (4470 +/- 936 ml versus 7023 +/- 1760 ml) in the group receiving both mannitol and albumin in the pump prime compared with the group receiving only lactated Ringer's solution. There were no differences between the groups with respect to both measured indices of oxygenation measured on return to ICU (alveolar-arterial oxygen tension difference (DA-aO2) or arterial oxygen tension to inspired oxygen fraction ratio (PaO2/FiO2), or time from ICU admission to extubation. PMID:8601041

  2. Human albumin solution for patients with cirrhosis and acute on chronic liver failure: Beyond simple volume expansion

    PubMed Central

    Valerio, Christopher; Theocharidou, Eleni; Davenport, Andrew; Agarwal, Banwari

    2016-01-01

    To provide an overview of the properties of human serum albumin (HSA), and to review the evidence for the use of human albumin solution (HAS) in critical illness, sepsis and cirrhosis. A MEDLINE search was performed using the terms “human albumin”, “critical illness”, “sepsis” and “cirrhosis”. The references of retrieved articles were reviewed manually. Studies published between 1980 and 2014 were selected based on quality criteria. Data extraction was performed by all authors. HSA is the main plasma protein contributing greatly to its oncotic pressure. HSA demonstrates important binding properties for endogenous and exogenous toxins, drugs and drug metabolites that account for its anti-oxidant and anti-inflammatory properties. In disease states, hypoalbuminaemia is secondary to decreased HSA production, increased loss or transcapillary leakage into the interstitial space. HSA function can be also altered in disease with reduced albumin binding capacity and increased production of modified isoforms. HAS has been used as volume expander in critical illness, but received criticism due to cost and concerns regarding safety. More recent studies confirmed the safety of HAS, but failed to show any survival benefit compared to the cheaper crystalloid fluids, therefore limiting its use. On the contrary, in cirrhosis there is robust data to support the efficacy of HAS for the prevention of circulatory dysfunction post-large volume paracentesis and in the context of spontaneous bacterial peritonitis, and for the treatment of hepato-renal syndrome and hypervolaemic hyponatraemia. It is likely that not only the oncotic properties of HAS are beneficial in cirrhosis, but also its functional properties, as HAS replaces the dysfunctional HSA. The role of HAS as the resuscitation fluid of choice in critically ill patients with cirrhosis, beyond the established indications for HAS use, should be addressed in future studies. PMID:26981172

  3. Pre-association of polynuclear platinum anticancer agents on a protein, human serum albumin. Implications for drug design†

    PubMed Central

    Montero, Eva I.; Benedetti, Brad T.; Mangrum, John B.; Oehlsen, Michael J.; Qu, Yun; Farrell, Nicholas P.

    2009-01-01

    The interactions of polynuclear platinum complexes with human serum albumin were studied. The compounds examined were the “non-covalent” analogs of the trinuclear BBR3464 as well as the dinuclear spermidine-bridged compounds differing in only the presence or absence of a central -NH2-+ (BBR3571 and analogs). Thus, closely-related compounds could be compared. Evidence for pre-association, presumably through electrostatic and hydrogen-bonding, was obtained from fluorescence and circular dichroism spectroscopy and Electrospray Ionization Mass Spectrometry (ESI-MS). In the case of those compounds containing Pt-Cl bonds, further reaction took place presumably through displacement by sulfur nucleophiles. The implications for protein pre-association and plasma stability of polynuclear platinum compounds are discussed. PMID:17992278

  4. Conformational changes of bovine plasma albumin prior to the salting-out of protein in concentrated salt solution.

    PubMed

    Sogami, M; Inouye, H; Nagaoka, S; Era, S

    1982-09-01

    By working at very low protein concentration (ca. 0.003%), it is possible to measure tryptophyl fluorescence intensity at 350 nm (F350) of bovine plasma albumin (BPA) as a function of pH under precipitating conditions (acidic concentrated salt solutions). Under such conditions, distinct changes in F350 were seen before the starting of precipitation of BPA and no further changes in F350 over the precipitating pH range. Comparison of pH-profiles monitored by F350 with those by solubility in the presence of various salts at various concentrations indicated that the change of solubility is observed after definite changes in conformation of the protein. PMID:7129758

  5. Sucrose dependence of solute retention on human serum albumin stationary phase: hydrophobic effect and surface tension considerations.

    PubMed

    Peyrin, E; Guillaume, Y C; Morin, N; Guinchard, C

    1998-07-15

    In a chromatographic system using human serum albumin (HSA) as a stationary phase, D,L dansyl amino acids as solutes, and sucrose as a mobile-phase modifier, a study on the surface tension effect of sugar on compound retention was carried out by varying the salting-out agent concentration c and the column temperature T. The thermodynamic parameters for solute transfer from the mobile to the stationary phase were determined from linear van't Hoff plots. An enthalpy-entropy compensation study revealed that the type of interaction between solute and HSA was independent of the molecular structure of the dansyl amino acids and the mobile-phase composition. An analysis of the experimental variations in the retention factor and the enantioselectivity values with c was performed using a theoretical model. It was shown that the decrease in solute retention accompanying the sucrose concentration increase was principally governed by a structural rearrangement of the binding cavity due to the increased surface tension effects. The cavity apolar residues were assumed to fold out of contact with the medium in order to reduce the surface area accessible to sucrose molecules, thus implying a restriction of the curvature radius of the cavity. Such behavior caused a decrease in the hydrophobic interaction for ligand binding on HSA explaining the observed thermodynamic parameter trends over the sucrose concentration range. PMID:9684542

  6. Unraveling the binding mechanism of asiatic acid with human serum albumin and its biological implications.

    PubMed

    Gokara, Mahesh; Malavath, Tirupathi; Kalangi, Suresh Kumar; Reddana, Pallu; Subramanyam, Rajagopal

    2014-01-01

    Asiatic acid (AsA), a naturally occurring pentacyclictriterpenoid found in Centella asiatica, plays a major role in neuroprotection, anticancer, antioxidant, and hepatoprotective activities. Human serum albumin (HSA), a blood plasma protein, participates in the regulation of plasma osmotic pressure and transports endogenous and exogenous substances. The study undertaken to analyze the drug-binding mechanisms of HSA is crucial in understanding the bioavailability of drugs. In this study, we analyzed the cytotoxic activity of AsA on HepG2 (human hepatocellular carcinoma) cell lines and its binding, conformational, docking, molecular simulation studies with HSA under physiological pH 7.2. These studies revealed a clear decrease in the viability of HepG2 cells upon exposure to AsA in a dose-dependent manner with an IC50 of 45 μM. Further studies showed the quenching of intrinsic fluorescence of HSA by AsA with a binding constant of KAsA = 3.86 ± 0.01 × 10(4) M(-1), which corresponds to the free energy of (ΔG) -6.3 kcal M(-1) at 25 °C. Circular dichroism (CD) studies revealed that there is a clear decrease in the α-helical content from 57.50 ± 2.4 to 50% ± 2.3 and an increase in the β-turns from 25 ± 0.65 to 29% ± 0.91 and random coils from 17.5% ± 0.95 to 21% ± 1.2, suggesting partial unfolding of HSA. Autodock studies revealed that the AsA is bound to the subdomain IIA with hydrophobic and hydrophilic interactions. From molecular dynamics, simulation data (RMSD, Rg and RMSF) emphasized the local conformational changes and rigidity of the residues of both HSA and HSA-AsA complexes. PMID:23844909

  7. AGE-modified albumin containing infusion solutions boosts septicaemia and inflammation in experimental peritonitis.

    PubMed

    Humpert, Per M; Lukic, Ivan K; Thorpe, Suzanne R; Hofer, Stefan; Awad, Ezzat M; Andrassy, Martin; Deemer, Elizabeth K; Kasper, Michael; Schleicher, Erwin; Schwaninger, Markus; Weigand, Markus A; Nawroth, Peter P; Bierhaus, Angelika

    2009-09-01

    HSA preparations for i.v. use are administered in critically ill patients. Although increasing intravascular osmotic pressure seems to be a pathophysiologically orientated treatment, clinical trials do not indicate a benefit for mortality in HSA-treated patients. Instead, there is evidence for inflammatory reactions upon infusion of different HSA batches. A neglected issue concerning the safety and quality of these therapeutics is processing-related post-transcriptional protein modifications, such as AGEs. We therefore tested the hypothesis that commercially available infusion solutions contain AGEs and studied whether these protein modifications influence outcome and inflammation in a murine model of sepsis induced by CLP. Screening of different HSA and Ig preparations in this study revealed an up to approximate tenfold difference in the amount of AGE modifications. Application of clinically relevant concentrations of CML-modified HSA in CLP led to increased inflammation and enhanced mortality in wild-type mice but not in mice lacking the RAGE. Lethality was paralleled by increased activation of the proinflammatory transcription factor NF-kappaB, NF-kappaB-dependent gene expression, and infiltration of inflammatory cells in the peritoneal cavity. This study implies that infusion solutions containing a high load of the AGE-modified protein have the potential to activate RAGE/NF-kappaB-mediated inflammatory reactions, causing increased mortality in experimental peritonitis. PMID:19401390

  8. Joint aqueous solutions of dextran and bovine serum albumin: coexistence of three liquid phases.

    PubMed

    Antonov, Yurij; Wolf, Bernhard A

    2014-06-10

    The phase diagram of the system water/dextran (DEX)/BSA was measured as well as modeled. On the experimental side, cloud points were determined and the coexisting phases were analyzed. The theoretical calculations use an approach capable of describing solutions of chain polymers and of globular proteins with the same formalism. The required thermodynamic input comes from experiments concerning the binary subsystems, except for the polymer blend for which one interaction parameter had to be adjusted. Both sources of information yield the same essential features: the existence of a large composition area of immiscibility, starting from the subsystem DEX/BSA and extending well into the region of dilute polymer solutions. This range is subdivided into three sections: one two-phase area at high polymer content, a two-phase area at low polymer content, and a three-phase region located in between. Measured and calculated phase diagrams match qualitatively; the reasons for the quantitative discrepancies are being discussed. PMID:24832129

  9. Preventing Aggregation of Recombinant Interferon beta-1b in Solution by Additives: Approach to an Albumin-Free Formulation

    PubMed Central

    Mahjoubi, Najmeh; Fazeli, Mohammad Reza; Dinarvand, Rassoul; Khoshayand, Mohammad Reza; Fazeli, Ahmad; Taghavian, Mohammad; Rastegar, Hossein

    2015-01-01

    Purpose: Aggregation suppressing additives have been used to stabilize proteins during manufacturing and storage. Interferonβ-1b is prone to aggregation because of being non-glycosylated. Aggregation behavior of albumin-free formulations of recombinant IFNβ-1b was explored using additives such as n-dodecyl-β-D-maltoside, Tween 20, arginine, glycine, trehalose and sucrose at different pH. Methods: Fractional factorial design was applied to select major factors affecting aggregation in solutions. Box-Behnken technique was used to optimize the best concentration of additives and protein. Results: Quadratic model was the best fitted model for particle size, OD350 and OD280/OD260. The optimal conditions of 0.2% n-Dodecyl-β-D-maltoside, 70 mM arginine, 189 mM trehalose and protein concentration of 0.50 mg/ml at pH 4 were achieved. A potency value of 91% ± 5% was obtained for the optimized formulation. Conclusion: This study shows that the combination of n-Dodecyl-β-D-maltoside, arginine and trehalose would demonstrate a significant stabilizing and anti-aggregating effect on the liquid formulation of interferonβ-1b. It can not only reduce the manufacturing costs but will also ease patient compliance. PMID:26819922

  10. Activation of mitogenic pathways by albumin in kidney proximal tubule epithelial cells: implications for the pathophysiology of proteinuric states.

    PubMed

    Dixon, R; Brunskill, N J

    1999-07-01

    Albumin is filtered into the proximal tubule in large quantities in nephrotic states. It has been proposed that this protein may have a toxic effect on tubular epithelial cells and may be responsible for the initiation of interstitial inflammation and scarring. The mitogenic effect of recombinant human albumin in wild-type opossum kidney cells and in similar cells transfected with a dominant negative p85 subunit (deltap85) of phopshatidylinositide 3-kinase (PI 3-kinase) has been studied. This study demonstrates that recombinant human albumin stimulates proliferation of opossum kidney cells in culture. This effect is mediated via PI 3-kinase, and is inhibited by wortmannin and deltap85 expression. Albumin stimulates PI 3-kinase activity in opossum kidney cells as determined by three different experimental procedures. Recombinant albumin also stimulates pp70(s6) kinase activity in a kinase cascade downstream of PI 3-kinase. Activity of pp70(s6) kinase is essential for albumin-induced proliferation of opossum kidney cells. It is proposed that this mitogenic pathway may have a critical role in proximal tubular homeostasis and pathophysiology of proteinuric states. PMID:10405204

  11. Structure and stability of 2S albumin-type peanut allergens: implications for the severity of peanut allergic reactions

    PubMed Central

    Lehmann, Katrin; Schweimer, Kristian; Reese, Gerald; Randow, Stefanie; Suhr, Martin; Becker, Wolf-Meinhard; Vieths, Stefan; Rösch, Paul

    2005-01-01

    Resistance to proteolytic enzymes and heat is thought to be a prerequisite property of food allergens. Allergens from peanut (Arachis hypogaea) are the most frequent cause of fatal food allergic reactions. The allergenic 2S albumin Ara h 2 and the homologous minor allergen Ara h 6 were studied at the molecular level with regard to allergenic potency of native and protease-treated allergen. A high-resolution solution structure of the protease-resistant core of Ara h 6 was determined by NMR spectroscopy, and homology modelling was applied to generate an Ara h 2 structure. Ara h 2 appeared to be the more potent allergen, even though the two peanut allergens share substantial cross-reactivity. Both allergens contain cores that are highly resistant to proteolytic digestion and to temperatures of up to 100 °C. Even though IgE antibody-binding capacity was reduced by protease treatment, the mediator release from a functional equivalent of a mast cell or basophil, the humanized RBL (rat basophilic leukaemia) cell, demonstrated that this reduction in IgE antibody-binding capacity does not necessarily translate into reduced allergenic potency. Native Ara h 2 and Ara h 6 have virtually identical allergenic potency as compared with the allergens that were treated with digestive enzymes. The folds of the allergenic cores are virtually identical with each other and with the fold of the corresponding regions in the undigested proteins. The extreme immunological stability of the core structures of Ara h 2 and Ara h 6 provides an explanation for the persistence of the allergenic potency even after food processing. PMID:16372900

  12. Microglial AGE-albumin is critical for neuronal death in Parkinson’s disease: a possible implication for theranostics

    PubMed Central

    Bayarsaikhan, Enkhjargal; Bayarsaikhan, Delger; Lee, Jaesuk; Son, Myeongjoo; Oh, Seyeon; Moon, Jeongsik; Park, Hye-Jeong; Roshini, Arivazhagan; Kim, Seung U; Song, Byoung-Joon; Jo, Seung-Mook; Byun, Kyunghee; Lee, Bonghee

    2015-01-01

    Advanced glycation end products (AGEs) are known to play an important role in the pathogenesis of neurodegenerative diseases, including Parkinson’s disease (PD), by inducing protein aggregation and cross-link, formation of Lewy body, and neuronal death. In this study, we observed that AGE-albumin, the most abundant AGE product in the human PD brain, is synthesized in activated microglial cells and accumulates in the extracellular space. AGE-albumin synthesis in human-activated microglial cells is distinctly inhibited by ascorbic acid and cytochalasin treatment. Accumulated AGE-albumin upregulates the receptor to AGE, leading to apoptosis of human primary dopamine (DA) neurons. In animal experiments, we observed reduced DA neuronal cell death by treatment with soluble receptor to AGE. Our study provides evidence that activated microglial cells are one of the main contributors in AGE-albumin accumulation, deleterious to DA neurons in human and animal PD brains. Finally, activated microglial AGE-albumin could be used as a diagnostic and therapeutic biomarker with high sensitivity for neurodegenerative disorders, including PD. PMID:27601894

  13. Albumin Test

    MedlinePlus

    ... to a variety of conditions in addition to malnutrition , a decrease in albumin needs to be evaluated ... can also be seen in inflammation , shock, and malnutrition . They may be seen with conditions in which ...

  14. Holograms of fluorescent albumin

    NASA Astrophysics Data System (ADS)

    Ordóñez-Padilla, M. J.; Olivares-Pérez, A.; Berriel-Valdos, L. R.; Mejias-Brizuela, N. Y.; Fuentes-Tapia, I.

    2011-09-01

    We report the characterization and analysis of photochromic films gallus gallus albumin as a matrix modified for holographic recording. Photo-oxidation of homogeneous mixtures prepared with albumin-propylene glycol, to combine chemically with aqueous solution of ammonium dichromate at certain concentrations. We analyzed the diffraction gratings, through the diffraction efficiency of the proposed material. Also, eosin was used as a fluorescent agent, so it is found that produces an inhibitory effect, thus decreasing the diffraction efficiency of the matrices prepared in near-identical circumstances. The work was to achieve stability of albumin films, were prepared with propylene glycol. Finally, experimental studies were performed with films when subjected to aqueous solution of eosin (fluorescent agent) to verify the ability to increase or decrease in diffraction efficiency.

  15. Nanotechnology in oncology: Characterization and in vitro release kinetics of cisplatin-loaded albumin nanoparticles: Implications in anticancer drug delivery

    PubMed Central

    Das, Saikat; Jagan, Lavanya; Isiah, Rajesh; Rajesh, B.; Backianathan, Selvamani; Subhashini, J.

    2011-01-01

    Context: Nanotechnology is an empowering technology that holds promise in cancer therapeutics by increasing the ratio of tumor control probability to normal tissue complication probability. It can increase the bioavailability of the drug at the target site, reduce the frequency of administration and reach otherwise lesser-accessible sites. The present study shows the feasibility of the cisplatin-loaded albumin nanoparticle as a sustained delivery system. Aims: Cisplatin is one of the most widely used chemotherapeutic agents for the treatment of malignant disorders. Conventional cisplatin formulation given as intravenous infusion has low bioavailability to the target organ in addition to significant side-effects, like ototoxicity and nephrotoxicity. The aim of this study was to develop a protein-based nanoparticulate system for sustained release of cisplatin. Materials and Methods: Nanoparticles were prepared by the coacervaton method of microcapsulation and chemical cross-linking with glutaraldehyde. Particle size was characterized by dynamic light scattering and transmission electron microscopy. Results and Conclusions: Using the coacervation method, nanoparticles of less than 70 nm diameter were produced. Drug encapsulation measured by ultraviolet spectroscopy varied from 30% to 80% for different ratios of cisplatin and protein. In vitro release kinetics shows that the nanoparticle-based formulation has biphasic release kinetics and is capable of sustained release compared with the free drug (80% release in 45 h). The study proves the feasibility of the albumin-based cisplatin nanoparticle formulation as a sustained release vehicle of cisplatin. PMID:21844995

  16. Interactions of a very long chain fatty acid with model membranes and serum albumin. Implications for the pathogenesis of adrenoleukodystrophy.

    PubMed Central

    Ho, J K; Moser, H; Kishimoto, Y; Hamilton, J A

    1995-01-01

    Adrenoleukodystrophy (ALD) is an inherited disorder of fatty acid metabolism marked by accumulation of very long chain saturated fatty acids (VLCFA), especially the 26-carbon acid, hexacosanoic acid (HA), in membranes and tissues. We have studied interactions of 13C-enriched HA with model membranes (phospholipid bilayer vesicles) and bovine serum albumin (BSA) by 13C NMR spectroscopy to compare properties of HA with those of typical dietary fatty acids. In phospholipid bilayers the carboxyl group of HA is localized in the aqueous interface, with an apparent pKa (7.4) similar to other fatty acids; the acyl chain must then penetrate very deeply into the membrane. Desorption of HA from vesicles (t1+2 = 3 h) is orders of magnitude slower than shorter chain fatty acids. In mixtures of vesicles and BSA, HA partitions much more favorably to phospholipid bilayers than typical fatty acids. BSA binds a maximum of only 1 mole of HA at one binding site. Calorimetric experiments show strong perturbations of acyl chains of phospholipids by HA. We predict that disruptive effects of VLCFA on cell membrane structure and function may explain the neurological manifestations of ALD patients. These effects will be further amplified by slow desorption of VLCFA from membranes and by the ineffective binding to serum albumin. PMID:7657817

  17. Theoretical and experimental studies on freezing point depression and vapor pressure deficit as methods to measure osmotic pressure of aqueous polyethylene glycol and bovine serum albumin solutions.

    PubMed

    Kiyosawa, Keitaro

    2003-05-01

    For survival in adverse environments where there is drought, high salt concentration or low temperature, some plants seem to be able to synthesize biochemical compounds, including proteins, in response to changes in water activity or osmotic pressure. Measurement of the water activity or osmotic pressure of simple aqueous solutions has been based on freezing point depression or vapor pressure deficit. Measurement of the osmotic pressure of plants under water stress has been mainly based on vapor pressure deficit. However, differences have been noted for osmotic pressure values of aqueous polyethylene glycol (PEG) solutions measured by freezing point depression and vapor pressure deficit. For this paper, the physicochemical basis of freezing point depression and vapor pressure deficit were first examined theoretically and then, the osmotic pressure of aqueous ethylene glycol and of PEG solutions were measured by both freezing point depression and vapor pressure deficit in comparison with other aqueous solutions such as NaCl, KCl, CaCl(2), glucose, sucrose, raffinose, and bovine serum albumin (BSA) solutions. The results showed that: (1) freezing point depression and vapor pressure deficit share theoretically the same physicochemical basis; (2) theoretically, they are proportional to the molal concentration of the aqueous solutions to be measured; (3) in practice, the osmotic pressure levels of aqueous NaCl, KCl, CaCl(2), glucose, sucrose, and raffinose solutions increase in proportion to their molal concentrations and there is little inconsistency between those measured by freezing point depression and vapor pressure deficit; (4) the osmotic pressure levels of aqueous ethylene glycol and PEG solutions measured by freezing point depression differed from the values measured by vapor pressure deficit; (5) the osmotic pressure of aqueous BSA solution measured by freezing point depression differed slightly from that measured by vapor pressure deficit. PMID:12834836

  18. Effect of Solution Conditions on the Nanoscale Intermolecular Interactions Between Human Serum Albumin and Low Grafting Density Surfaces of Poly(ethylene oxide)

    NASA Astrophysics Data System (ADS)

    Rixman, Monica; Macias, Celia; Dean, Delphine; Ortiz, Christine

    2003-03-01

    The first step in the biological rejection response to an implanted blood-contacting biomaterial is the non-covalent adsorption of proteins onto the surface, which triggers a cascade reaction ultimately resulting in thrombus formation. Using the technique of high resolution force spectroscopy, we have quantified the nonspecific intermolecular forces between fatty acid-complexed human serum albumin (HSA) covalently attached to a cantilever probe tip and individual end-grafted poly(ethylene oxide) mushrooms. In order to help elucidate the molecular origins of the constituent forces (e.g. steric, electrostatic, van der Waals), experiments were performed varying both the solution environmental conditions (e.g. ionic strength, removal of the bound fatty acids, and the addition of the antihydrophobic agent isopropanol), and the probe deflection rate.

  19. Concurrent zero-dimensional and one-dimensional biomineralization of gold from a solution of Au3+ and bovine serum albumin

    NASA Astrophysics Data System (ADS)

    Hartings, Matthew R.; Benjamin, Noah; Briere, Floriene; Briscione, Maria; Choudary, Omar; Fisher, Tamra L.; Flynn, Laura; Ghias, Elizabeth; Harper, Michaela; Khamis, Nader; Koenigsknecht, Catherine; Lazor, Klare; Moss, Steven; Robbins, Elaine; Schultz, Susan; Yaman, Samiye; Haverhals, Luke M.; Trulove, Paul C.; De Long, Hugh C.; Miller, Abigail E.; Fox, Douglas M.

    2013-12-01

    A technique was developed for preparing a novel material that consists of gold nanoparticles trapped within a fiber of unfolded proteins. These fibers are made in an aqueous solution that contains HAuCl4 and the protein, bovine serum albumin (BSA). By changing the ratio of gold to BSA in solution, two different types of outcomes are observed. At lower gold to BSA ratios (30-120), a purple solution results after heating the mixture at 80 °C for 4 h. At higher gold to BSA ratios (130-170), a clear solution containing purple fibers results after heating the mixture at 80 °C for 4 h. UV-Vis spectroscopy and light scattering techniques show growth in nanocolloid size as gold to BSA ratio rises above 100. Data indicate that, for the higher gold to BSA ratios, the gold is sequestered within the solid material. The material mass, visible by eye, appears to be an aggregation of smaller individual fibers. Scanning electron microscopy and transmission electron microscopy indicate that these fibers are primarily one-dimensional aggregates, which can display some branching, and can be as narrow as 400 nm in size. The likely mechanism for the synthesis of the novel material is discussed.

  20. CHARACTERIZATION OF INTERACTION KINETICS BETWEEN CHIRAL SOLUTES AND HUMAN SERUM ALBUMIN BY USING HIGH-PERFORMANCE AFFINITY CHROMATOGRAPHY AND PEAK PROFILING

    PubMed Central

    Tong, Zenghan; Hage, David S.

    2011-01-01

    Peak profiling and high-performance columns containing immobilized human serum albumin (HSA) were used to study the interaction kinetics of chiral solutes with this protein. This approach was tested using the phenytoin metabolites 5-(3-hydroxyphenyl)-5-phenylhydantoin (m-HPPH) and 5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) as model analytes. HSA columns provided some resolution of the enantiomers for each phenytoin metabolite, which made it possible to simultaneously conduct kinetic studies on each chiral form. The dissociation rate constants for these interactions were determined by using both the single flow rate and multiple flow rate peak profiling methods. Corrections for non-specific interactions with the support were also considered. The final estimates obtained at pH 7.4 and 37°C for the dissociation rate constants of these interactions were 8.2–9.6 s−1 for the two enantiomers of m-HPPH and 3.2–4.1 s−1 for the enantiomers of p-HPPH. These rate constants agreed with previous values that have been reported for other drugs and solutes that have similar affinities and binding regions on HSA. The approach used in this report was not limited to phenytoin metabolites or HSA but could be applied to a variety of other chiral solutes and proteins. This method could also be adopted for use in the rapid screening of drug-protein interactions. PMID:21872871

  1. Light Scattering Analysis of Mono- and Multi-PEGylated Bovine Serum Albumin in Solution: Role of Composition on Structure and Interactions.

    PubMed

    Ferebee, Rachel; Hakem, Ilhem F; Koch, Amelie; Chen, Maggie; Wu, Yi; Loh, Derek; Wilson, David C; Poole, Jennifer L; Walker, Jeremy P; Fytas, George; Bockstaller, Michael R

    2016-05-26

    The effect of polymer conjugation on the interactions between proteins in solution is evaluated by systematic analysis of the second virial coefficient (A2) for the particular example of single- and double-PEGylated bovine serum albumin (PEG-BSA) in dilute PBS solution. The effect of PEGylation on A2 is found to sensitively depend on both the composition and the distribution of PEG segments within the conjugate. Most importantly, at a given PEG volume fraction, A2 significantly increases with the degree of polymerization of tethered chains. Hence, a lesser number of long chains is more effective in solubilizing BSA than a correspondingly larger number of short chains. Analysis of the hydrodynamic radii of protein-PEG conjugates suggests that the increased solubility is concurrent with a structural transition in the case of high molecular PEG grafts that results in compact core-shell-type structures. The results reveal a link between the composition, structure, and solubility of polymer conjugates that might benefit the understanding of their biochemical characteristics and their design for functional material applications. PMID:27149093

  2. 21 CFR 640.80 - Albumin (Human).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... a sterile solution of the albumin derived from human plasma. (b) Source material. The source material of Albumin (Human) shall be plasma recovered from Whole Blood prepared as prescribed in §§ 640.1 through 640.5, or Source Plasma prepared as prescribed in §§ 640.60 through 640.76. (c) Additives...

  3. 21 CFR 640.80 - Albumin (Human).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... a sterile solution of the albumin derived from human plasma. (b) Source material. The source material of Albumin (Human) shall be plasma recovered from Whole Blood prepared as prescribed in §§ 640.1 through 640.5, or Source Plasma prepared as prescribed in §§ 640.60 through 640.76. (c) Additives...

  4. 21 CFR 640.80 - Albumin (Human).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... a sterile solution of the albumin derived from human plasma. (b) Source material. The source material of Albumin (Human) shall be plasma recovered from Whole Blood prepared as prescribed in §§ 640.1 through 640.5, or Source Plasma prepared as prescribed in §§ 640.60 through 640.76. (c) Additives...

  5. 21 CFR 640.80 - Albumin (Human).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... a sterile solution of the albumin derived from human plasma. (b) Source material. The source material of Albumin (Human) shall be plasma recovered from Whole Blood prepared as prescribed in §§ 640.1 through 640.5, or Source Plasma prepared as prescribed in §§ 640.60 through 640.76. (c) Additives...

  6. 21 CFR 640.80 - Albumin (Human).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... a sterile solution of the albumin derived from human plasma. (b) Source material. The source material of Albumin (Human) shall be plasma recovered from Whole Blood prepared as prescribed in §§ 640.1 through 640.5, or Source Plasma prepared as prescribed in §§ 640.60 through 640.76. (c) Additives...

  7. Albumin inhibits platelet-activating factor (PAF)-induced responses in platelets and macrophages: implications for the biologically active form of PAF.

    PubMed Central

    Grigoriadis, G.; Stewart, A. G.

    1992-01-01

    1. Platelet-activating factor (PAF) binds with high affinity to albumin leading Clay et al. (1990) to suggest that the active form of PAF is the albumin-PAF complex. 2. In the present study the proposal that albumin-bound, rather than monomeric PAF, is the active form of PAF at PAF receptors was critically evaluated by examining the effect of albumin on the potency of PAF in isolated platelets and macrophages. 3. Bovine serum albumin inhibited concentration-dependently PAF-induced responses in platelets and macrophages. The most probable explanation of this finding is that BSA reduced the concentration of free PAF. 4. Thus, we conclude that free PAF, rather than the albumin-PAF complex is the active form. Consequently, local concentrations of albumin will influence profoundly the potency of endogenously released PAF. Moreover, estimates of the affinity of PAF for PAF receptors made in buffers containing BSA, underestimate the true affinity of PAF for its receptors by approximately 3 orders of magnitude. PMID:1330167

  8. Albumin and multiple sclerosis.

    PubMed

    LeVine, Steven M

    2016-01-01

    Leakage of the blood-brain barrier (BBB) is a common pathological feature in multiple sclerosis (MS). Following a breach of the BBB, albumin, the most abundant protein in plasma, gains access to CNS tissue where it is exposed to an inflammatory milieu and tissue damage, e.g., demyelination. Once in the CNS, albumin can participate in protective mechanisms. For example, due to its high concentration and molecular properties, albumin becomes a target for oxidation and nitration reactions. Furthermore, albumin binds metals and heme thereby limiting their ability to produce reactive oxygen and reactive nitrogen species. Albumin also has the potential to worsen disease. Similar to pathogenic processes that occur during epilepsy, extravasated albumin could induce the expression of proinflammatory cytokines and affect the ability of astrocytes to maintain potassium homeostasis thereby possibly making neurons more vulnerable to glutamate exicitotoxicity, which is thought to be a pathogenic mechanism in MS. The albumin quotient, albumin in cerebrospinal fluid (CSF)/albumin in serum, is used as a measure of blood-CSF barrier dysfunction in MS, but it may be inaccurate since albumin levels in the CSF can be influenced by multiple factors including: 1) albumin becomes proteolytically cleaved during disease, 2) extravasated albumin is taken up by macrophages, microglia, and astrocytes, and 3) the location of BBB damage affects the entry of extravasated albumin into ventricular CSF. A discussion of the roles that albumin performs during MS is put forth. PMID:27067000

  9. Recombinant albumin monolayers on latex particles.

    PubMed

    Sofińska, Kamila; Adamczyk, Zbigniew; Kujda, Marta; Nattich-Rak, Małgorzata

    2014-01-14

    The adsorption of recombinant human serum albumin (rHSA) on negatively charged polystyrene latex micro-particles was studied at pH 3.5 and the NaCl concentration range of 10(-3) to 0.15 M. The electrophoretic mobility of latex monotonically increased with the albumin concentration in the suspension. The coverage of adsorbed albumin was quantitatively determined using the depletion method, where the residual protein concentration was determined by electrokinetic measurements and AFM imaging. It was shown that albumin adsorption was irreversible. Its maximum coverage on latex varied between 0.7 mg m(-2) for 10(-3) M NaCl to 1.3 mg m(-2) for 0.15 M NaCl. The latter value matches the maximum coverage previously determined for human serum albumin on mica using the streaming potential method. The increase in the maximum coverage was interpreted in terms of reduced electrostatic repulsion among adsorbed molecules. These facts confirm that albumin adsorption at pH 3.5 is governed by electrostatic interactions and proceeds analogously to colloid particle deposition. The stability of albumin monolayers was measured in additional experiments where changes in the latex electrophoretic mobility and the concentration of free albumin in solutions were monitored over prolonged time periods. Based on these experimental data, a robust procedure of preparing albumin monolayers on latex particles of well-controlled coverage and molecule distribution was proposed. PMID:24354916

  10. Human podocytes perform polarized, caveolae-dependent albumin endocytosis

    PubMed Central

    Dobrinskikh, Evgenia; Okamura, Kayo; Kopp, Jeffrey B.; Doctor, R. Brian

    2014-01-01

    The renal glomerulus forms a selective filtration barrier that allows the passage of water, ions, and small solutes into the urinary space while restricting the passage of cells and macromolecules. The three layers of the glomerular filtration barrier include the vascular endothelium, glomerular basement membrane (GBM), and podocyte epithelium. Podocytes are capable of internalizing albumin and are hypothesized to clear proteins that traverse the GBM. The present study followed the fate of FITC-labeled albumin to establish the mechanisms of albumin endocytosis and processing by podocytes. Confocal imaging and total internal reflection fluorescence microscopy of immortalized human podocytes showed FITC-albumin endocytosis occurred preferentially across the basal membrane. Inhibition of clathrin-mediated endocytosis and caveolae-mediated endocytosis demonstrated that the majority of FITC-albumin entered podocytes through caveolae. Once internalized, FITC-albumin colocalized with EEA1 and LAMP1, endocytic markers, and with the neonatal Fc receptor, a marker for transcytosis. After preloading podocytes with FITC-albumin, the majority of loaded FITC-albumin was lost over the subsequent 60 min of incubation. A portion of the loss of albumin occurred via lysosomal degradation as pretreatment with leupeptin, a lysosomal protease inhibitor, partially inhibited the loss of FITC-albumin. Consistent with transcytosis of albumin, preloaded podocytes also progressively released FITC-albumin into the extracellular media. These studies confirm the ability of podocytes to endocytose albumin and provide mechanistic insight into cellular mechanisms and fates of albumin handling in podocytes. PMID:24573386

  11. Comparative solution equilibrium studies on pentamethylcyclopentadienyl rhodium complexes of 2,2'-bipyridine and ethylenediamine and their interaction with human serum albumin.

    PubMed

    Enyedy, Éva A; Mészáros, János P; Dömötör, Orsolya; Hackl, Carmen M; Roller, Alexander; Keppler, Bernhard K; Kandioller, Wolfgang

    2015-11-01

    Complex formation equilibrium processes of the (N,N) donor containing 2,2'-bipyridine (bpy) and ethylenediamine (en) with (η(5)-pentamethylcyclopentadienyl)rhodium(III) were investigated in aqueous solution via pH-potentiometry, (1)H NMR spectroscopy, and UV-vis spectrophotometry in the absence and presence of chloride ions. The structure of [RhCp*(en)Cl]ClO4 (Cp*, pentamethylcyclopentadienyl) was also studied by single-crystal X-ray diffraction. pKa values of 8.56 and 9.58 were determined for [RhCp*(bpy)(H2O)](2+) and [RhCp*(en)(H2O)](2+), respectively resulting in the formation of negligible amount of mixed hydroxido complexes at pH 7.4. Stability and the H2O/Cl(-) co-ligand exchange constants of bpy and en complexes considerably exceed those of the bidentate O-donor deferiprone. The strong affinity of the bpy and en complexes to chloride ions most probably contributes to their low antiproliferative effect. Interactions between human serum albumin (HSA) and [RhCp*(H2O)3](2+), its complexes formed with deferiprone, bpy and en were also monitored by (1)H NMR spectroscopy, ultrafiltration/UV-vis and spectrofluorometry. Numerous binding sites (≥ 8) are available for [RhCp*(H2O)3](2+); and the interaction takes place most probably via covalent bonds through the imidazole nitrogen of His. According to the various fluorescence studies [RhCp*(H2O)3](2+) binds on sites I and II, and coordination of surface side chain donor atoms of the protein is also feasible. The binding of the bpy and en complex is weaker and slower compared to that of [RhCp*(H2O)3](2+), and formation of ternary HSA-RhCp*-ligand adducts was proved. In the case of the deferiprone complex, the RhCp* fragment is cleaved off when HSA is loaded with low equivalents of the compound. PMID:26364131

  12. Protein Crystal Serum Albumin

    NASA Technical Reports Server (NTRS)

    1998-01-01

    As the most abundant protein in the circulatory system albumin contributes 80% to colloid osmotic blood pressure. Albumin is also chiefly responsible for the maintenance of blood pH. It is located in every tissue and bodily secretion, with extracellular protein comprising 60% of total albumin. Perhaps the most outstanding property of albumin is its ability to bind reversibly to an incredible variety of ligands. It is widely accepted in the pharmaceutical industry that the overall distribution, metabolism, and efficiency of many drugs are rendered ineffective because of their unusually high affinity for this abundant protein. An understanding of the chemistry of the various classes of pharmaceutical interactions with albumin can suggest new approaches to drug therapy and design. Principal Investigator: Dan Carter/New Century Pharmaceuticals

  13. Experimental investigation of the serum albumin fascia microstructure

    NASA Astrophysics Data System (ADS)

    Buzoverya, M. E.; Shcherbak, Yu. P.; Shishpor, I. V.

    2012-09-01

    The results of theoretical and experimental investigation of biological liquids are reported. Structural effects observed in fascias are considered with account of the molecular features of albumin and the concept of supramolecular organization of polymers. It is revealed that the morphology of human serum albumin fascias depends on the concentration and quality of the solvent. It is shown that the water-salt fascias of albumin are more structured than water solutions with the same concentration.

  14. Structure of Serum Albumin

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.; Ho, Joseph X.

    1994-01-01

    Because of its availability, low cost, stability, and unusual ligand-binding properties, serum albumin has been one of the mst extensively studied and applied proteins in biochemistry. However, as a protein, albumin is far from typical, and the widespread interest in and application of albumin have not been balanced by an understanding of its molecular structure. Indeed, for more than 30 years structural information was surmised based solely on techniques such as hydrodynamics, low-angle X-ray scattering, and predictive methods.

  15. Physical chemistry of supersaturated solutions and implications for oral absorption.

    PubMed

    Taylor, Lynne S; Zhang, Geoff G Z

    2016-06-01

    Amorphous solid dispersion (ASD) formulations are widely used for delivery of poorly soluble drugs for dissolution enhancement and bioavailability improvement. When administered, ASDs often exhibit fast dissolution to yield supersaturated solutions. The physical chemistry of these supersaturated solutions is not well understood. This review will discuss the concepts of solubility, supersaturation, and the connection to membrane transport rate. Liquid-liquid phase separation (LLPS), which occurs when the amorphous solubility is exceeded, leading to solutions with interesting properties is extensively discussed as a phenomenon that is relevant to all enabling formulations. The multiple physical processes occurring during dissolution of the ASD and during oral absorption are analyzed. The beneficial reservoir effect of a system that has undergone LLPS is demonstrated, both experimentally and conceptually. It is believed that formulations that rapidly supersaturate and subsequently undergo LLPS, with maintenance of the supersaturation at this maximum value throughout the absorption process, i.e. those that exhibit "spring and plateau" behavior, will give superior performance in terms of absorption. PMID:27013254

  16. Smartphone based point-of-care detector of urine albumin

    NASA Astrophysics Data System (ADS)

    Cmiel, Vratislav; Svoboda, Ondrej; Koscova, Pavlina; Provaznik, Ivo

    2016-03-01

    Albumin plays an important role in human body. Its changed level in urine may indicate serious kidney disorders. We present a new point-of-care solution for sensitive detection of urine albumin - the miniature optical adapter for iPhone with in-built optical filters and a sample slot. The adapter exploits smart-phone flash to generate excitation light and camera to measure the level of emitted light. Albumin Blue 580 is used as albumin reagent. The proposed light-weight adapter can be produced at low cost using a 3D printer. Thus, the miniaturized detector is easy to use out of lab.

  17. Binding of Sulpiride to Seric Albumins

    PubMed Central

    da Silva Fragoso, Viviane Muniz; de Morais Coura, Carla Patrícia; Hoppe, Luanda Yanaan; Soares, Marília Amável Gomes; Silva, Dilson; Cortez, Celia Martins

    2016-01-01

    The aim of this work was to study the interaction of sulpiride with human serum albumin (HSA) and bovine serum albumin (BSA) through the fluorescence quenching technique. As sulpiride molecules emit fluorescence, we have developed a simple mathematical model to discriminate the quencher fluorescence from the albumin fluorescence in the solution where they interact. Sulpiride is an antipsychotic used in the treatment of several psychiatric disorders. We selectively excited the fluorescence of tryptophan residues with 290 nm wavelength and observed the quenching by titrating HSA and BSA solutions with sulpiride. Stern-Volmer graphs were plotted and quenching constants were estimated. Results showed that sulpiride form complexes with both albumins. Estimated association constants for the interaction sulpiride–HSA were 2.20 (±0.08) × 104 M−1, at 37 °C, and 5.46 (±0.20) × 104 M−1, at 25 °C. Those for the interaction sulpiride-BSA are 0.44 (±0.01) × 104 M−1, at 37 °C and 2.17 (±0.04) × 104 M−1, at 25 °C. The quenching intensity of BSA, which contains two tryptophan residues in the peptide chain, was found to be higher than that of HSA, what suggests that the primary binding site for sulpiride in albumin should be located next to the sub domain IB of the protein structure. PMID:26742031

  18. Binding of Sulpiride to Seric Albumins.

    PubMed

    da Silva Fragoso, Viviane Muniz; de Morais Coura, Carla Patrícia; Hoppe, Luanda Yanaan; Soares, Marília Amável Gomes; Silva, Dilson; Cortez, Celia Martins

    2016-01-01

    The aim of this work was to study the interaction of sulpiride with human serum albumin (HSA) and bovine serum albumin (BSA) through the fluorescence quenching technique. As sulpiride molecules emit fluorescence, we have developed a simple mathematical model to discriminate the quencher fluorescence from the albumin fluorescence in the solution where they interact. Sulpiride is an antipsychotic used in the treatment of several psychiatric disorders. We selectively excited the fluorescence of tryptophan residues with 290 nm wavelength and observed the quenching by titrating HSA and BSA solutions with sulpiride. Stern-Volmer graphs were plotted and quenching constants were estimated. Results showed that sulpiride form complexes with both albumins. Estimated association constants for the interaction sulpiride-HSA were 2.20 (±0.08) × 10⁴ M(-1), at 37 °C, and 5.46 (±0.20) × 10⁴ M(-1), at 25 °C. Those for the interaction sulpiride-BSA are 0.44 (±0.01) × 10⁴ M(-1), at 37 °C and 2.17 (±0.04) × 10⁴ M(-1), at 25 °C. The quenching intensity of BSA, which contains two tryptophan residues in the peptide chain, was found to be higher than that of HSA, what suggests that the primary binding site for sulpiride in albumin should be located next to the sub domain IB of the protein structure. PMID:26742031

  19. Cancer stem cells and immunoresistance: clinical implications and solutions.

    PubMed

    Codony-Servat, Jordi; Rosell, Rafael

    2015-12-01

    Tumor cells can be contained, but not eliminated, by traditional cancer therapies. A cell minor subpopulation is able to evade attack from therapies and may have cancer stem cell (CSC) characteristics, including self-renewal, multiple differentiation and tumor initiation (tumor initiating cells, or TICs). Thus, CSCs/TICs, aided by the microenvironment, produce more differentiated, metastatic cancer cells which the immune system detects and interacts with. There are three phases to this process: elimination, equilibrium and escape. In the elimination phase the immune system recognizes and destroys most of the tumor cells. Then the latency phase begins, consisting of equilibrium between immunological elimination and tumor cell growth. Finally, a minor attack-resistant subpopulation escapes and forms a clinically detectable tumor mass. Herein we review current knowledge of immunological characterization of CSCs/TICs. Due to the correlation between CTCs/TICs and drug resistance and metastasis, we also comment on the crucial role of key molecules involved in controlling CSCs/TICs properties; such molecules are essential to detect and destroy CSCs/TICs. Monoclonal antibodies, antibody constructs and vaccines have been designed to act against CSCs/TICs, with demonstrated efficacy in human cancer xenografts and some antitumor activity in human clinical studies. Therefore, therapeutic strategies that selectively target CSCs/TICs warrant further investigation. Better understanding of the interaction between CSCs and tumor immunology may help to identify strategies to eradicate the minor subpopulation that escapes conventional therapy attack, thus providing a solution to the problem of drug resistance and metastasis. PMID:26798578

  20. Cancer stem cells and immunoresistance: clinical implications and solutions

    PubMed Central

    Rosell, Rafael

    2015-01-01

    Tumor cells can be contained, but not eliminated, by traditional cancer therapies. A cell minor subpopulation is able to evade attack from therapies and may have cancer stem cell (CSC) characteristics, including self-renewal, multiple differentiation and tumor initiation (tumor initiating cells, or TICs). Thus, CSCs/TICs, aided by the microenvironment, produce more differentiated, metastatic cancer cells which the immune system detects and interacts with. There are three phases to this process: elimination, equilibrium and escape. In the elimination phase the immune system recognizes and destroys most of the tumor cells. Then the latency phase begins, consisting of equilibrium between immunological elimination and tumor cell growth. Finally, a minor attack-resistant subpopulation escapes and forms a clinically detectable tumor mass. Herein we review current knowledge of immunological characterization of CSCs/TICs. Due to the correlation between CTCs/TICs and drug resistance and metastasis, we also comment on the crucial role of key molecules involved in controlling CSCs/TICs properties; such molecules are essential to detect and destroy CSCs/TICs. Monoclonal antibodies, antibody constructs and vaccines have been designed to act against CSCs/TICs, with demonstrated efficacy in human cancer xenografts and some antitumor activity in human clinical studies. Therefore, therapeutic strategies that selectively target CSCs/TICs warrant further investigation. Better understanding of the interaction between CSCs and tumor immunology may help to identify strategies to eradicate the minor subpopulation that escapes conventional therapy attack, thus providing a solution to the problem of drug resistance and metastasis. PMID:26798578

  1. Glycated serum albumin stimulates expression of endothelial cell specific molecule-1 in human umbilical vein endothelial cells: Implication in diabetes mediated endothelial dysfunction.

    PubMed

    Nirala, Bikesh K; Perumal, Vivekanandan; Gohil, Nivedita K

    2015-07-01

    Pro-inflammatory conditions induced by products of protein glycation in diabetes substantially enhance the risk of endothelial dysfunction and related vascular complications. Endothelial cell specific molecule-1 (ESM-1) or endocan has been demonstrated as a potential biomarker in cancer and sepsis. Its role in diabetes-induced pathologies remains unknown. The expression of ESM-1 gene is under cytokine regulation, indicating its role in endothelium-dependent pathological disorders. In this study, we investigated the effect of advanced glycated human serum albumin (AGE-HSA) on the production of ESM-1. We show that AGE-HSA exerts a modulating role on the expression of ESM-1 in human umbilical vein endothelial cells. It up-regulates expression of ESM-1 protein in a dose-dependent manner which correlates with its messenger RNA (mRNA) transcription. RAGE and galectin-3, both AGE receptors, show antagonistic action on its expression. While gene silencing of RAGE has down-regulatory effect, that of galectin-3 has up-regulatory effect on AGE-induced expression of ESM-1. Inhibition of MAPKKK and JNK pathways did not alter the expression. In contrast, phosphatidylinositol 3 kinase (PI3K) inhibition significantly up-regulated ESM-1 expression. In conclusion, these results suggest that AGE-induced activation of human umbilical vein endothelial cells promotes formation of endocan which is an endothelial dysfunction marker and may be related to vascular disease in diabetes. PMID:25963575

  2. Effect of linoleic acid albumin in a dilution solution and long-term equilibration for freezing of bovine spermatozoa with poor freezability.

    PubMed

    Takahashi, T; Itoh, R; Nishinomiya, H; Katoh, M; Manabe, N

    2012-02-01

    Despite normal eucrasia, mating desire and semen quality, sire bulls sometimes have spermatozoa with poor freezing tolerance. This study assessed effects of the addition of linoleic acid albumin (LAA) and long-term (LT) equilibrium to frozen semen on their sperm freezing tolerance. Immediately after collection using an artificial vagina and a breeding mount, semen was diluted with yolk citrate buffer; then, it was cooled slowly to 4°C during more than 5 h. Equilibrium treatment at 4°C was applied using the same extender supplemented with glycerol. Semen of bull A, with low sperm freezing tolerance, was treated with 1 mg/ml of LAA added to the first extender. The equilibrium treatment at 4°C was prolonged to 30 h. Significantly higher motility rates were obtained for the LT + LAA-treated sperm before and after freezing-thawing. However, for semen of bulls B and C with normal sperm freezing tolerance, the LT + LAA treatment barely exhibited a small effect on the motility rate. Almost no difference was found among bulls A, B and C in the motility rates of LT + LAA-treated sperm after freezing-thawing. No difference of fertility was apparent on LT + LAA-treated frozen sperm in comparison with normal sperm in embryonic collection and in vitro fertilization. It was not an aberration of fertility in vivo or in vitro. In addition, the conception rate of artificial insemination did not have a difference, and a normal calf was obtained. Results show that addition of LAA to an extender for frozen bovine spermatozoa and 30 h of low-temperature equilibrium might improve the motility of freezing-thawing spermatozoa with poor freezability. Sperm exhibited normal fertilization capability and ontogenic capability. PMID:21635578

  3. Facile cell patterning on an albumin-coated surface.

    PubMed

    Yamazoe, Hironori; Uemura, Toshimasa; Tanabe, Toshizumi

    2008-08-19

    Fabrication of micropatterned surfaces to organize and control cell adhesion and proliferation is an indispensable technique for cell-based technologies. Although several successful strategies for creating cellular micropatterns on substrates have been demonstrated, a complex multistep process and requirements for special and expensive equipment or materials limit their prevalence as a general experimental tool. To circumvent these problems, we describe here a novel facile fabrication method for a micropatterned surface for cell patterning by utilizing the UV-induced conversion of the cell adhesive property of albumin, which is the most abundant protein in blood plasma. An albumin-coated surface was prepared by cross-linking albumin with ethylene glycol diglycidyl ether and subsequent casting of the cross-linked albumin solution on the cell culture dish. While cells did not attach to the albumin surface prepared in this way, UV exposure renders the surface cell-adhesive. Thus, surface micropatterning was achieved simply by exposing the albumin-coated surface to UV light through a mask with the desired pattern. Mouse fibroblast L929 cells were inoculated on the patterned albumin substrates, and cells attached and spread in a highly selective manner according to the UV-irradiated pattern. Although detailed investigation of the molecular-level mechanism concerning the change in cell adhesiveness of the albumin-coated surface is required, the present results would give a novel facile method for the fabrication of cell micropatterned surfaces. PMID:18627191

  4. Solvation Phenomena in Dilute Solutions: Formal, Experimental Evidence, and Modeling Implications

    SciTech Connect

    Chialvo, Ariel A

    2013-01-01

    We review the fundamentals underlying a general molecular-based formalism for the microscopic interpretation of the solvation phenomena involving sparingly soluble solutes in compressible media, an approach that hinges around the unambiguous splitting of the species correlation function integrals into short-(finite) and long-ranged (diverging) contributions at infinite dilution, where this condition is taken as the reference system for the derivation of composition expansions. Then, we invoke the formalism (a) to illustrate the well-behaved nature of the solvation contributions to the mechanical partial molecular properties of solutes at infinite dilution, (b) to guide the development of, and provide molecular-based support to, the macroscopic modeling of high-temperature dilute aqueous-electrolyte solutions, (c) to study solvation effects on the kinetic rate constants of reactions in near-critical solvents in an attempt to understand from a microscopic perspective the macroscopic evidence regarding the thermodynamic pressure effects, and (d) to interpret the microscopic mechanism behind synergistic solvation effects involving either co-solutes or co-solvents, and provide a molecular argument on the unsuitability of the van der Waals one-fluid (vdW-1f) mixing rules for the 2 description of weakly attractive solutes in compressible solvents. Finally, we develop thermodynamically consistent perturbation expansions, around the infinite dilution reference, for the species residual properties in binary and ternary mixtures, and discuss the theoretical and modeling implications behind ad hoc first-order truncated expansions.

  5. Aggrecan, an Unusual Polyelectrolyte: Review of Solution Behavior and Physiological Implications

    PubMed Central

    Chandran, Preethi L.; Horkay, Ferenc

    2011-01-01

    Aggrecan is a high molecular weight, bottlebrush-shaped, negative-charged biopolymer that forms supermolecular complexes with hyaluronic acid. In the extracellular matrix of cartilage, aggrecan-hyaluronic acid complexes are interspersed in the collagen matrix and provide the osmotic properties required to resist deswelling under compressive load. In this review we compile aggrecan solution behavior from different experimental techniques, and discuss them in the context of concentration regimes that were identified in osmotic pressure experiments. At low concentration, aggrecan exhibits microgel-like behavior. With increasing concentration, the bottlebrushes self assemble into large complexes. In the physiological concentration range (2 < caggrecan < 8 % w/w), the physical properties of the solution are dominated by repulsive electrostatic interactions between aggrecan complexes. We discuss the consequences of the bottlebrush architecture on the polyelectrolyte characteristics of the aggrecan molecule, and its implications for cartilage properties and function. PMID:21884828

  6. Glycated serum albumin: a potential disease marker and an intermediate index of diabetes control.

    PubMed

    Raghav, Alok; Ahmad, Jamal

    2014-01-01

    Glycation is a non-enzymatic spontaneous process in proteins which has remarkable impact on its physical and functional aspect. This alteration with addition of carbohydrate residue to human serum albumin leads to several pathological events such as diabetic nephropathy, neuropathy, retinopathy and cardiovascular complications. Human serum albumin is the major protein and is most susceptible to non-enzymatic glycation. Structural and biological properties of functional albumin alter due to the addition of reducing carbohydrate to free amino terminal residues vivo. These irreversible changes in functional albumin are stable which makes this modified albumin as new gold standard future diagnostic marker in diabetes associated complications. Glycated albumin can be used to determine the glycemic control due to short half life than erythrocytes which makes it an alternate reliable disease marker in diabetes. In this review, Human serum albumin glycation has been overviewed, stating concept of glycation and sites that are prone to this modifications. Impact of non-enzymatic addition of carbohydrate to albumin's structural and biological properties has also been elaborated. Accurate measurements of glycated albumin with implications of new highly sensitive techniques have also been described briefly. Interestingly human serum albumin imposed glycation can serve as future tool not for diagnosing diabetes but also its potential in assessment of diabetes associated complications. PMID:25311816

  7. The dynamic implication of focal mechanism solutions of Wenchuan earthquake sequence

    NASA Astrophysics Data System (ADS)

    Hu, X.; Cui, X.; Chen, L.

    2010-12-01

    At 14:28 CST on May 12, 2008, the disastrous MS8.0 Wenchuan earthquake took place in Sichuan province of China, followed by tens of thousands of aftershocks. It occurred on the Longmenshan fault zone which is a high-angle inland over-thrust fault. What is the corresponding tectonic implication behind the focal mechanism is an important issue to realize the dynamic mechanism of Wenchuan earthquake sequence. In order to reveal it, our research as following is carried out. 1) We extensively collected digital waveform records, seriously and strictly read out P wave first motion, used more accurate locating results, employed the improved grid point test method, computed the focal mechanism solutions of Wenchuan earthquake sequence, and gave out 125 reliable focal mechanism solutions (M≥4.0,including a M3.9 earthquake result). The result shows that most of the earthquakes are thrust or strike-slip. The focal mechanism solutions have characteristic of subsection distribution. The P axis mainly distribute in direction of E-W within a certain range. 2) According to the main faults information and fine medium parameters, using ANSYS software, we established a three-dimensional elastic finite element model of the Longmenshan fault zone and its surrounding areas. According to Global Position System observations, considering three representative patterns of tectonic deformation velocity varying with depth, we loaded three different boundary conditions and got each numerical simulation result of the tectonic stress field in this region. The simulation results of the three patterns consistently show that the orientation of the principal compressive stress is almost E-W in Longmenshan fault zone and its surrounding area. And from north to south, there is a clockwise rotation within a narrow range. The result is consistent with the previous research in these areas. 3) Based on the numerical simulation results of tectonic stress field of three structural deformation patterns

  8. Cellular Specificity of the Blood–CSF Barrier for Albumin Transfer across the Choroid Plexus Epithelium

    PubMed Central

    Liddelow, Shane A.; Dzięgielewska, Katarzyna M.; Møllgård, Kjeld; Whish, Sophie C.; Noor, Natassya M.; Wheaton, Benjamin J.; Gehwolf, Renate; Wagner, Andrea; Traweger, Andreas; Bauer, Hannelore; Bauer, Hans-Christian; Saunders, Norman R.

    2014-01-01

    To maintain the precise internal milieu of the mammalian central nervous system, well-controlled transfer of molecules from periphery into brain is required. Recently the soluble and cell-surface albumin-binding glycoprotein SPARC (secreted protein acidic and rich in cysteine) has been implicated in albumin transport into developing brain, however the exact mechanism remains unknown. We postulate that SPARC is a docking site for albumin, mediating its uptake and transfer by choroid plexus epithelial cells from blood into cerebrospinal fluid (CSF). We used in vivo physiological measurements of transfer of endogenous (mouse) and exogenous (human) albumins, in situ Proximity Ligation Assay (in situ PLA), and qRT-PCR experiments to examine the cellular mechanism mediating protein transfer across the blood–CSF interface. We report that at all developmental stages mouse albumin and SPARC gave positive signals with in situ PLAs in plasma, CSF and within individual plexus cells suggesting a possible molecular interaction. In contrast, in situ PLA experiments in brain sections from mice injected with human albumin showed positive signals for human albumin in the vascular compartment that were only rarely identifiable within choroid plexus cells and only at older ages. Concentrations of both endogenous mouse albumin and exogenous (intraperitoneally injected) human albumin were estimated in plasma and CSF and expressed as CSF/plasma concentration ratios. Human albumin was not transferred through the mouse blood–CSF barrier to the same extent as endogenous mouse albumin, confirming results from in situ PLA. During postnatal development Sparc gene expression was higher in early postnatal ages than in the adult and changed in response to altered levels of albumin in blood plasma in a differential and developmentally regulated manner. Here we propose a possible cellular route and mechanism by which albumin is transferred from blood into CSF across a sub-population of

  9. Cellular specificity of the blood-CSF barrier for albumin transfer across the choroid plexus epithelium.

    PubMed

    Liddelow, Shane A; Dzięgielewska, Katarzyna M; Møllgård, Kjeld; Whish, Sophie C; Noor, Natassya M; Wheaton, Benjamin J; Gehwolf, Renate; Wagner, Andrea; Traweger, Andreas; Bauer, Hannelore; Bauer, Hans-Christian; Saunders, Norman R

    2014-01-01

    To maintain the precise internal milieu of the mammalian central nervous system, well-controlled transfer of molecules from periphery into brain is required. Recently the soluble and cell-surface albumin-binding glycoprotein SPARC (secreted protein acidic and rich in cysteine) has been implicated in albumin transport into developing brain, however the exact mechanism remains unknown. We postulate that SPARC is a docking site for albumin, mediating its uptake and transfer by choroid plexus epithelial cells from blood into cerebrospinal fluid (CSF). We used in vivo physiological measurements of transfer of endogenous (mouse) and exogenous (human) albumins, in situ Proximity Ligation Assay (in situ PLA), and qRT-PCR experiments to examine the cellular mechanism mediating protein transfer across the blood-CSF interface. We report that at all developmental stages mouse albumin and SPARC gave positive signals with in situ PLAs in plasma, CSF and within individual plexus cells suggesting a possible molecular interaction. In contrast, in situ PLA experiments in brain sections from mice injected with human albumin showed positive signals for human albumin in the vascular compartment that were only rarely identifiable within choroid plexus cells and only at older ages. Concentrations of both endogenous mouse albumin and exogenous (intraperitoneally injected) human albumin were estimated in plasma and CSF and expressed as CSF/plasma concentration ratios. Human albumin was not transferred through the mouse blood-CSF barrier to the same extent as endogenous mouse albumin, confirming results from in situ PLA. During postnatal development Sparc gene expression was higher in early postnatal ages than in the adult and changed in response to altered levels of albumin in blood plasma in a differential and developmentally regulated manner. Here we propose a possible cellular route and mechanism by which albumin is transferred from blood into CSF across a sub-population of specialised

  10. Seeded growth of hydroxyapatite in the presence of dissolved albumin.

    PubMed

    Gilman, H; Hukins, D W

    1994-07-01

    Hydroxyapatite (HAP) crystals were grown from a supersaturated solution by the addition of a suspension of seed crystals at a controlled pH value of 7.4 and a temperature of 37 degrees C. The degree of supersaturation was comparable to that in biological fluids and was such that all HAP precipitated would be expected to deposit on the seeds. Albumin was added to some of the solutions to give a concentration in the range 75-250 micrograms cm-3. Samples of solution were removed at known times after the addition of seed crystals and their calcium ion concentrations were determined by atomic absorption spectroscopy. The decrease in the dissolved calcium concentration was taken to be a measure of crystal growth. In the absence of seeds, no decrease in calcium concentration occurred. The initial rate of HAP growth decreased linearly with albumin concentration, i.e., albumin was found to inhibit crystal growth. Inhibition kinetics were consistent with a Langmuir model in which a single albumin molecule was capable of binding to more than one growth site on the crystal surface. Comparison with published results indicated that albumin was a less potent inhibitor of HAP growth than phosphoproteins but was a more potent inhibitor than magnesium or citrate ions. PMID:8046435

  11. Albumin impregnated vascular grafts: albumin resorption and tissue reactions.

    PubMed

    Cziperle, D J; Joyce, K A; Tattersall, C W; Henderson, S C; Cabusao, E B; Garfield, J D; Kim, D U; Duhamel, R C; Greisler, H P

    1992-01-01

    This study aimed to determine the kinetics of albumin resorption from and the healing of two types of albumin impregnated Vasculour II (Bard Cardiovascular) Dacron grafts (ACG-A and ACG-B) using whole blood preclotted Vasculour II Dacron grafts (without albumin) as controls (PCC). Prostheses measuring 4 mm ID x 50 mm length were implanted in the aortoiliac position in 24 dogs (ACG-A n = 12, ACG-B n = 24, PCC n = 12) and explanted after 1, 2 4, and 6 months. Platelet count, platelet aggregometry to 10(-5) M ADP, prothrombin time (PT), and partial thromboplastin time (PTT) were determined preoperatively and at explantation. Sections of the explanted grafts were assayed for human albumin by immunohistochemical techniques utilizing a rabbit polyclonal mono-specific antibody for human albumin followed by the addition of a biotinylated goat anti-rabbit IgG. Immunoperoxidase staining was then performed using Avidin D horse-radish peroxidase. Histology of the grafts (light microscopy, scanning electron microscopy, and transmission electron microscopy) as well as percent thrombus free surface area (TFSA) by computerized planimetry were also determined. Seven of 48 grafts were occluded (85.4% patency) with no difference among the three groups. Platelet aggregometry was not predictive of graft patency. No change in PT or PTT occurred nor was there any difference among the three groups. Retained albumin was detected in every one-month explant but not beyond that time, with the sensitivity for detecting human albumin in this assay being 20 mg albumin per gram of Dacron. All ACG explants at one month revealed inner capsular fibrin coagula not present in PCC specimens.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1388174

  12. Albumin administration in the acutely ill: what is new and where next?

    PubMed Central

    2014-01-01

    Albumin solutions have been used worldwide for the treatment of critically ill patients since they became commercially available in the 1940s. However, their use has become the subject of criticism and debate in more recent years. Importantly, all fluid solutions have potential benefits and drawbacks. Large multicenter randomized studies have provided valuable data regarding the safety of albumin solutions, and have begun to clarify which groups of patients are most likely to benefit from their use. However, many questions remain related to where exactly albumin fits within our fluid choices. Here, we briefly summarize some of the physiology and history of albumin use in intensive care before offering some evidence-based guidance for albumin use in critically ill patients. PMID:25042164

  13. The transport of albumin across the ferret in vitro whole trachea.

    PubMed Central

    Webber, S E; Widdicombe, J G

    1989-01-01

    1. The whole trachea of the ferret has been isolated in vitro in an organ bath and used to study the transport of bovine serum albumin (BSA) and two dextrans (70,000 and 9000 Da) from external buffer solution to air-filled lumen, assessed by fluorescent-labelled tracers. 2. In control conditions, when mucus secretion was not stimulated by drugs, the concentration of albumin in the lumen was over half that in the buffer, and about six times greater than those of the two dextrans. 3. Methacholine and phenylephrine caused large increases in mucus secretion and albumin output and decreases in albumin concentration. The responses were proportional to drug concentration. We concluded that albumin output is increased but diluted with submucosal gland secretion. 4. Salbutamol caused a small increase in mucus secretion and large increases in output and concentration of albumin. The concentration of albumin became greater than that in the external buffer medium. The responses were proportional to concentration of salbutamol. 5. Histamine increased mucus secretion and albumin output and concentration. 6. None of the four drugs increased the output of dextran-70,000. Methacholine and phenylephrine increased the output of dextran-9000, but to a far less extent than for albumin. 7. Cooling the trachea and buffer to 4 degrees C almost abolished the stimulation of mucus and albumin outputs due to methacholine. 8. Increasing the concentration of albumin external to the trachea did not proportionally increase albumin secretion, the logarithmic relationship suggesting saturation of an active transport system. 9. We conclude that albumin is secreted by active transport into the tracheal lumen, and that the rate of transport can be augmented by salbutamol to build up a higher concentration in the lumen than in the external buffer. Images Fig. 7 PMID:2476558

  14. A new theory of bubble stability: Implications for nanobubbles at surfaces and in bulk solution

    NASA Astrophysics Data System (ADS)

    Craig, Vincent

    2013-11-01

    Nanobubbles on hydrophobic surfaces can be imaged using Atomic Force Microscopy and are implicated in the very long-range attraction measured between hydrophobic surfaces. However, the widely accepted theory of bubble dissolution predicts that small bubbles under the influence of Laplace pressure should rapidly dissolve resulting in bubble lifetimes of less than a second. Such short lifetimes should preclude nanobubbles from having an effect on surface force measurements or being observed by AFM, yet nanobubbles are readily observed by AFM and widely implicated in force measurements between hydrophobic surfaces. This has led to a number of attempts at describing their unexpected stability, though no explanation is currently widely accepted. Additionally, nanobubbles have contact angles substantially greater (measured through the more dense liquid phase) than the equivalent macroscopic contact angle. It is clear that nanobubbles at surfaces pose a number of problems that are yet to be resolved. Additionally, recent reports of long-lived nanobubbles in bulk solution add to the mystery. Here we present a new theory describing the stability of nanobubbles. We calculate their lifetimes as a function of gas supersaturation and explain the long lifetimes observed. The same theory predicts that bulk nanobubbles should be stable under certain circumstances. Further, in an extension of this work we explain the difference in contact angle between the nanoscopic and macroscopic measurements and describe in detail the process by which nanobubbles are formed during solvent exchange. Experimental evidence is presented supporting this new approach and showing that this theoretical framework has parallels in other nucleated systems. This work was supported by an ARC Future Fellowship.

  15. Formation of bovine serum albumin associates with zinc tetra(4,4'-carboxy)phenylamino- and tetra-(4,4'-carboxy)phenoxy phthalocyanines in aqueous-organic solutions at 298 K

    NASA Astrophysics Data System (ADS)

    Lebedeva, N. Sh.; Popova, T. E.; Mal'kova, E. A.; Gubarev, Yu. A.

    2013-12-01

    The states of water-soluble complexes of zinc phthalocyanine containing -O-C6H4-COONa and -NH-C6H4-COONa substituents in aqueous and organic media are studied. The type of dimerization is determined for each phthalocyanine. Phthalocyanine interaction with bovine serum albumin is studied with respect to the association equilibria. It is shown that phthalocyanines are localized in protein subdomains IB and IIA, and the interaction between protein and phthalocyanines is of a multicenter character.

  16. Near Earth Objects and Cascading Effects from the Policy Perspective: Implications from Problem and Solution Definition

    NASA Astrophysics Data System (ADS)

    Lindquist, Eric

    2016-04-01

    The characterization of near-Earth-objects (NEOs) in regard to physical attributes and potential risk and impact factors presents a complex and complicates scientific and engineering challenge. The societal and policy risks and impacts are no less complex, yet are rarely considered in the same context as material properties or related factors. Further, NEO impacts are typically considered as discrete events, not as initial events in a dynamic cascading system. The objective of this contribution is to position the characterization of NEOs within the public policy process domain as a means to reflect on the science-policy nexus in regard to risks and multi-hazard impacts associated with these hazards. This will be accomplished through, first, a brief overview of the science-policy nexus, followed by a discussion of policy process frameworks, such as agenda setting and the multiple streams model, focusing events, and punctuated equilibrium, and their application and appropriateness to the problem of NEOs. How, too, for example, does NEO hazard and risk compare with other low probability, high risk, hazards in regard to public policy? Finally, we will reflect on the implications of alternative NEO "solutions" and the characterization of the NEO "problem," and the political and public acceptance of policy alternatives as a way to link NEO science and policy in the context of the overall NH9.12 panel.

  17. Characterization of NEOs from the Policy Perspective: Implications from Problem and Solution Definitions

    NASA Astrophysics Data System (ADS)

    Lindquist, E.

    2015-12-01

    The characterization of near-Earth-objects (NEOs) in regard to physical attributes and potential risk and impact factors presents a complex and complicates scientific and engineering challenge. The societal and policy risks and impacts are no less complex, yet are rarely considered in the same context as material properties or related factors. The objective of this contribution is to position the characterization of NEOs within the public policy process domain as a means to reflect on the science-policy nexus in regard to risks associated with NEOs. This will be accomplished through, first, a brief overview of the science-policy nexus, followed by a discussion of several policy process frameworks, such as agenda setting and the multiple streams model, focusing events, and punctuated equilibrium, and their application and appropriateness to the problem of NEOs. How, too, for example, does NEO hazard and risk compare with other low probability, high risk, hazards in regard to public policy? Finally, we will reflect on the implications of alternative NEO "solutions" and the characterization of the NEO "problem," and the political and public acceptance of policy alternatives as a way to link NEO science and policy in the context of the overall NH004 panel.

  18. Industrial stabilizers caprylate and N-acetyltryptophanate reduce the efficacy of albumin in liver patients.

    PubMed

    Stange, Jan; Stiffel, Melanie; Goetze, Anne; Strube, Sabrina; Gruenert, Juliane; Klammt, Sebastian; Mitzner, Steffen; Koball, Sebastian; Liebe, Stefan; Reisinger, Emil

    2011-06-01

    Liver failure is associated with an accumulation of toxic molecules that exert an affinity to albumin. Some of them have vasoactive activity. So far, albumin has been used as a plasma expander to improve the available circulating blood volume. However, recent studies have suggested that albumin is more effective than starch for this indication. It has not been reported yet whether the industrial stabilizers octanoate and N-acetyltryptophanate, added to albumin, occupy binding sites for vasoactive substances. The aim of this study was to determine whether the presence of the industrial stabilizers octanoate and caprylate has an impact on the effect of the albumin-binding function or circulating blood volume in patients with cirrhosis, portal hypertension, and an indication for albumin. In 25 patients who received albumin via an inline infusion filter that depleted stabilizers, there was an improvement of albumin binding, and there was less deterioration of circulating blood volume and renal function in comparison with a control group. Further studies are needed to confirm the results and identify the potential socioeconomic side effects of industrial stabilizers in commercial albumin solutions. PMID:21618691

  19. Amadori albumin in diabetic nephropathy.

    PubMed

    Neelofar, Km; Ahmad, Jamal

    2015-01-01

    Nonenzymatic glycation of macromolecules in diabetes mellitus (DM) is accelerated due to persistent hyperglycemia. Reducing sugar such as glucose reacts non enzymatically with free €-amino groups of proteins through series of reactions forming Schiff bases. These bases are converted into Amadori product and further into AGEs. Non enzymatic glycation has the potential to alter the biological, structural and functional properties of macromolecules both in vitro and in vivo. Studies have suggested that amadori as well as AGEs are involved in the micro-macro vascular complications in DM, but most studies have focused on the role of AGEs in vascular complications of diabetes. Recently putative AGE-induced patho-physiology has shifted attention from the possible role of amadori-modified proteins, the predominant form of the glycated proteins in the development of the diabetic complications. Human serum albumin (HSA), the most abundant protein in circulation contains 59 lysine and 23 arginine residues that could, in theory be involved in glycation. Albumin has dual nature, first as a marker of intermediate glycation and second as a causative agent of the damage of tissues. Among the blood proteins, hemoglobin and albumin are the most common proteins that are glycated. HSA with a shorter half life than RBC, appears to be an alternative marker of glycemic control as it can indicate blood glucose status over a short period (2-3 weeks) and being unaffected by RBCs life span and variant haemoglobin, anemia etc which however, affect HbA1c. On the other hand, Amadori albumin may accumulate in the body tissues of the diabetic patients and participate in secondary complications. Amadori-albumin has potential role in diabetic glomerulosclerosis due to long term hyperglycaemia and plays an important role in the pathogenesis of diabetic nephropathy. This review is an approach to compile both the nature of glycated albumin as a damaging agent of tissues and as an intermediate

  20. PRODUCTION OF UNIFORMLY SIZED SERUM ALBUMIN AND DEXTROSE MICROBUBBLES

    PubMed Central

    Borrelli, Michael J.; O’Brien, William D.; Bernock, Laura J.; Williams, Heather R.; Hamilton, Eric; Wu, Jonah; Oelze, Michael L.; Culp, William C.

    2011-01-01

    Uniformly-sized preparations with average microbubble (MB) diameters from 1 µm to 7 µm were produced reliably by sonicating decafluorobutane-saturated solutions of serum albumin and dextrose. Detailed protocols for producing and size-separating the MBs are presented, along with the effects that changing each production parameter (serum albumin concentration, sonication power, sonication time, etc.) had on MB size distribution and acoustic stability. These protocols can be used to produce MBs for experimental applications or serve as templates for developing new protocols that yield MBs with physical and acoustic properties better suited to specific applications. Size stability and ultrasonic performance quality control tests were developed to assure that successive MB preparations perform identically and to distinguish the physical and acoustic properties of identically sized MBs produced with different serum albumin-dextrose formulations and sonication parameters. MBs can be stored at 5°C for protracted periods (2 weeks to one year depending on formulation). PMID:21689961

  1. Biocompatibility of electrospun human albumin: a pilot study.

    PubMed

    Noszczyk, B H; Kowalczyk, T; Łyżniak, M; Zembrzycki, K; Mikułowski, G; Wysocki, J; Kawiak, J; Pojda, Z

    2015-01-01

    Albumin is rarely used for electrospinning because it does not form fibres in its native globular form. This paper presents a novel method for electrospinning human albumin from a solution containing pharmaceutical grade protein and 25% polyethylene oxide (PEO) used as the fibre-forming agent. After spontaneous cross-linking at body temperature, with no further chemicals added, the fibres become insoluble and the excess PEO can be washed out. Albumin deposited along the fibres retains its native characteristics, such as its non-adhesiveness to cells and its susceptibility for degradation by macrophages. To demonstrate this we evaluated the mechanical properties, biocompatibility and biodegradability of this novel product. After subcutaneous implantation in mice, albumin mats were completely resorbable within six days and elicited only a limited local inflammatory response. In vitro, the mats suppressed cell attachment and migration. As this product is inexpensive, produced from human pharmaceutical grade albumin without chemical modifications, retains its native protein properties and fulfils the specific requirements for anti-adhesive dressings, its clinical use can be expedited. We believe that it could specifically be used when treating paediatric patients with epidermolysis bullosa, in whom non-healing wounds occur after minor hand injuries which lead to rapid adhesions and devastating contractures. PMID:25727172

  2. Heat denatured/aggregated albumin-based biomaterial: effects of preparation parameters on biodegradability and mechanical properties.

    PubMed

    Rohanizadeh, Ramin; Kokabi, Nima

    2009-12-01

    Albumin-based biomaterials prepared using heat-aggregation or cross-linking agents have been used in various biomedical applications such as solder materials for laser-assisted tissue welding, anti-bacterial coatings and drug carriers. In this study, solid albumin-based materials were prepared via heat aggregation of albumin solution. The study aimed to determine the influences of the preparation parameters such as albumin concentration in solution, solution pH and temperature, on the mechanical properties as well as the biodegradation rate of heat-aggregated albumin-based materials. The results demonstrated that the materials prepared from the albumin solution with the pH of 8.5 had the highest mechanical strength. Augmenting the albumin concentration in solution led to an increase in mechanical strength, and the materials prepared from the solution with isoelectric albumin pH (pH 4.8) possessed the lowest biodegradation rate and those prepared at pH 12 showed the highest biodegradation rate. PMID:19847625

  3. Comparative efficiency of final endodontic cleansing procedures in removing a radioactive albumin from root canal systems

    SciTech Connect

    Cecic, P.A.; Peters, D.D.; Grower, M.F.

    1984-09-01

    Fifty-six teeth were initially instrumented, with the use of seven irrigants or irrigant combinations, and filled with radioactive albumin. The study then showed the relative ability of three final endodontic procedures (copious reirrigation with saline solution, drying with paper points, and reassuring patency of the canal with the final instrument) to remove the albumin. Even after copious irrigation, each additional procedure removed statistically significant amounts of albumin. Alternating an organic solvent and an inorganic solvent did appear to leave the canal system in the optimal condition for final cleansing procedures. The study then correlated the relative efficiency of irrigation alone versus instrumentation plus irrigation in removing the remaining albumin from the canal systems. Reinstrumentation plus copious irrigation removed significantly more albumin than copious irrigation alone.

  4. Albumin-deficient mouse models for studying metabolism of human albumin and pharmacokinetics of albumin-based drugs

    PubMed Central

    Roopenian, Derry C; Low, Benjamin E; Christianson, Gregory J; Proetzel, Gabriele; Sproule, Thomas J; Wiles, Michael V

    2015-01-01

    Serum albumin is the major determinant of blood colloidal osmotic pressure acting as a depot and distributor of compounds including drugs. In humans, serum albumin exhibits an unusually long half-life mainly due to protection from catabolism by neonatal Fc receptor (FcRn)-mediated recycling. These properties make albumin an attractive courier of therapeutically-active compounds. However, pharmaceutical research and development of albumin-based therapeutics has been hampered by the lack of appropriate preclinical animal models. To overcome this, we developed and describe the first mouse with a genetic deficiency in albumin and its incorporation into an existing humanized FcRn mouse model, B6.Cg-Fcgrttm1Dcr Tg(FCGRT)32Dcr/DcrJ (Tg32). Albumin-deficient strains (Alb-/-) were created by TALEN-mediated disruption of the albumin (Alb) gene directly in fertilized oocytes derived from Tg32 mice and its non-transgenic background control, C57BL/6J (B6). The resulting Alb-/- strains are analbuminemic but healthy. Intravenous administration of human albumin to Tg32-Alb-/- mFcRn-/- hFcRnTg/Tg) mice results in a remarkably extended human albumin serum half-life of ∼24 days, comparable to that found in humans, and in contrast to half-lives of 2.6–5.8 d observed in B6, B6-Alb-/- and Tg32 strains. This striking increase can be explained by the absence of competing endogenous mouse albumin and the presence of an active human FcRn. These novel albumin-deficient models provide unique tools for investigating the biology and pathobiology of serum albumin and are a more appropriate rodent surrogates for evaluating human serum albumin pharmacokinetics and albumin-based compounds. PMID:25654695

  5. Podocytes degrade endocytosed albumin primarily in lysosomes.

    PubMed

    Carson, John M; Okamura, Kayo; Wakashin, Hidefumi; McFann, Kim; Dobrinskikh, Evgenia; Kopp, Jeffrey B; Blaine, Judith

    2014-01-01

    Albuminuria is a strong, independent predictor of chronic kidney disease progression. We hypothesize that podocyte processing of albumin via the lysosome may be an important determinant of podocyte injury and loss. A human urine derived podocyte-like epithelial cell (HUPEC) line was used for in vitro experiments. Albumin uptake was quantified by Western blot after loading HUPECs with fluorescein-labeled (FITC) albumin. Co-localization of albumin with lysosomes was determined by confocal microscopy. Albumin degradation was measured by quantifying FITC-albumin abundance in HUPEC lysates by Western blot. Degradation experiments were repeated using HUPECs treated with chloroquine, a lysosome inhibitor, or MG-132, a proteasome inhibitor. Lysosome activity was measured by fluorescence recovery after photo bleaching (FRAP). Cytokine production was measured by ELISA. Cell death was determined by trypan blue staining. In vivo, staining with lysosome-associated membrane protein-1 (LAMP-1) was performed on tissue from a Denys-Drash trangenic mouse model of nephrotic syndrome. HUPECs endocytosed albumin, which co-localized with lysosomes. Choloroquine, but not MG-132, inhibited albumin degradation, indicating that degradation occurs in lysosomes. Cathepsin B activity, measured by FRAP, significantly decreased in HUPECs exposed to albumin (12.5% of activity in controls) and chloroquine (12.8%), and declined further with exposure to albumin plus chloroquine (8.2%, p<0.05). Cytokine production and cell death were significantly increased in HUPECs exposed to albumin and chloroquine alone, and these effects were potentiated by exposure to albumin plus chloroquine. Compared to wild-type mice, glomerular staining of LAMP-1 was significantly increased in Denys-Drash mice and appeared to be most prominent in podocytes. These data suggest lysosomes are involved in the processing of endocytosed albumin in podocytes, and lysosomal dysfunction may contribute to podocyte injury and

  6. Podocytes Degrade Endocytosed Albumin Primarily in Lysosomes

    PubMed Central

    Carson, John M.; Okamura, Kayo; Wakashin, Hidefumi; McFann, Kim; Dobrinskikh, Evgenia; Kopp, Jeffrey B.; Blaine, Judith

    2014-01-01

    Albuminuria is a strong, independent predictor of chronic kidney disease progression. We hypothesize that podocyte processing of albumin via the lysosome may be an important determinant of podocyte injury and loss. A human urine derived podocyte-like epithelial cell (HUPEC) line was used for in vitro experiments. Albumin uptake was quantified by Western blot after loading HUPECs with fluorescein-labeled (FITC) albumin. Co-localization of albumin with lysosomes was determined by confocal microscopy. Albumin degradation was measured by quantifying FITC-albumin abundance in HUPEC lysates by Western blot. Degradation experiments were repeated using HUPECs treated with chloroquine, a lysosome inhibitor, or MG-132, a proteasome inhibitor. Lysosome activity was measured by fluorescence recovery after photo bleaching (FRAP). Cytokine production was measured by ELISA. Cell death was determined by trypan blue staining. In vivo, staining with lysosome-associated membrane protein-1 (LAMP-1) was performed on tissue from a Denys-Drash trangenic mouse model of nephrotic syndrome. HUPECs endocytosed albumin, which co-localized with lysosomes. Choloroquine, but not MG-132, inhibited albumin degradation, indicating that degradation occurs in lysosomes. Cathepsin B activity, measured by FRAP, significantly decreased in HUPECs exposed to albumin (12.5% of activity in controls) and chloroquine (12.8%), and declined further with exposure to albumin plus chloroquine (8.2%, p<0.05). Cytokine production and cell death were significantly increased in HUPECs exposed to albumin and chloroquine alone, and these effects were potentiated by exposure to albumin plus chloroquine. Compared to wild-type mice, glomerular staining of LAMP-1 was significantly increased in Denys-Drash mice and appeared to be most prominent in podocytes. These data suggest lysosomes are involved in the processing of endocytosed albumin in podocytes, and lysosomal dysfunction may contribute to podocyte injury and

  7. Complexation of serum albumins and triton X-100: Quenching of tryptophan fluorescence and analysis of the rotational diffusion of complexes

    NASA Astrophysics Data System (ADS)

    Vlasova, I. M.; Vlasov, A. A.; Saletskii, A. M.

    2016-07-01

    The polarized and nonpolarized fluorescence of bovine serum albumin and human serum albumin in Triton X-100 solutions is studied at different pH values. Analysis of the constants of fluorescence quenching for BSA and HSA after adding Triton X-100 and the hydrodynamic radii of BSA/HSA-detergent complexes show that the most effective complexation between both serum albumins and Triton X-100 occurs at pH 5.0, which lies near the isoelectric points of the proteins. Complexation between albumin and Triton X-100 affects the fluorescence of the Trp-214 residing in the hydrophobic pockets of both BSA and HSA.

  8. Crystals of Serum Albumin for Use in Genetic Engineering and Rational Drug Design

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor)

    1996-01-01

    Serum albumin crystal forms have been produced which exhibit superior x-ray diffraction quality. The crystals are produced from both recombinant and wild-type human serum albumin, canine, and baboon serum albumin and allow the performance of drug-binding studies as well as genetic engineering studies. The crystals are grown from solutions of polyethylene glycol or ammonium sulphate within prescribed limits during growth times from one to several weeks and include the following space groups: P2(sub 1), C2, P1.

  9. Spontaneous formation of small sized albumin/acacia coacervate particles.

    PubMed

    Burgess, D J; Singh, O N

    1993-07-01

    Microgel coacervate particles form spontaneously on mixing aqueous solutions of oppositely charged albumin and acacia, under specific conditions of pH, ionic strength, and polyion concentration, close to but not at the optimum conditions for maximum coacervate yield. The mean particle diameter of these coacervate particles is approximately 6 microns when suspended in aqueous media, as determined by HIAC/Royco particle analysis. The geometric standard deviation of the particles falls in the range 1.2-1.9 microns. The particle size was not dependent on the method of emulsification of the coacervate in the equilibrium phase, or on the stirring speed applied during the manufacturing process. The microgel particles were stable on storage, for periods up to forty-six days, without the addition of a chemical cross-linking agent, or the application of heat. Stability was measured with respect to the change in particle size of samples stored at different temperatures. The non-cross-linked microcapsules were also shown to be stable on pH change, to pH values outside the coacervation pH range. At the optimum conditions for maximum coacervate yield the albumin/acacia system formed a very viscous coacervate phase, which was unsuitable for microcapsule preparation. The rheological properties of albumin/acacia and gelatin/acacia complex coacervates optimized for maximum coacervate yield were compared. The albumin/acacia coacervate was shown to be three orders of magnitude more viscous than the gelatin/acacia system. PMID:8105049

  10. Megalin mediates transepithelial albumin clearance from the alveolar space of intact rabbit lungs

    PubMed Central

    Buchäckert, Yasmin; Rummel, Sebastian; Vohwinkel, Christine U; Gabrielli, Nieves M; Grzesik, Benno A; Mayer, Konstantin; Herold, Susanne; Morty, Rory E; Seeger, Werner; Vadász, István

    2012-01-01

    The alveolo-capillary barrier is effectively impermeable to large solutes such as proteins. A hallmark of acute lung injury/acute respiratory distress syndrome is the accumulation of protein-rich oedema fluid in the distal airspaces. Excess protein must be cleared from the alveolar space for recovery; however, the mechanisms of protein clearance remain incompletely understood. In intact rabbit lungs 29.8 ± 2.2% of the radio-labelled alveolar albumin was transported to the vascular compartment at 37°C within 120 min, as assessed by real-time measurement of 125I-albumin clearance from the alveolar space. At 4°C or 22°C significantly lower albumin clearance (3.7 ± 0.4 or 16.2 ± 1.1%, respectively) was observed. Deposition of a 1000-fold molar excess of unlabelled albumin into the alveolar space or inhibition of cytoskeletal rearrangement or clathrin-dependent endocytosis largely inhibited the transport of 125I-albumin to the vasculature, while administration of unlabelled albumin to the vascular space had no effect on albumin clearance. Furthermore, albumin uptake capacity was measured as about 0.37 mg ml−1 in cultured rat lung epithelial monolayers, further highlighting the (patho)physiological relevance of active alveolar epithelial protein transport. Moreover, gene silencing and pharmacological inhibition of the multi-ligand receptor megalin resulted in significantly decreased albumin binding and uptake in monolayers of primary alveolar type II and type I-like and cultured lung epithelial cells. Our data indicate that clearance of albumin from the distal air spaces is facilitated by an active, high-capacity, megalin-mediated transport process across the alveolar epithelium. Further understanding of this mechanism is of clinical importance, since an inability to clear excess protein from the alveolar space is associated with poor outcome in patients with acute lung injury/acute respiratory distress syndrome. PMID:22826129

  11. A Humanized Mouse Model to Study Human Albumin and Albumin Conjugates Pharmacokinetics.

    PubMed

    Low, Benjamin E; Wiles, Michael V

    2016-01-01

    Albumin is a large, highly abundant protein circulating in the blood stream which is regulated and actively recycled via the neonatal Fc receptor (FcRn). In humans this results in serum albumin having an exceptional long half-life of ~21 days. Some time ago it was realized that these intrinsic properties could be harnessed and albumin could be used as a privileged drug delivery vehicle. However, active development of albumin based therapeutics has been hampered by the lack of economic, relevant experimental models which can accurately recapitulate human albumin metabolism and pharmacokinetics. In mice for example, introduced human albumin is not recycled and is catabolized rapidly. This is mainly due to the failure of mouse FcRn to bind human albumin consequently, human albumin has a half-life of only 2-3 days in mice. To overcome this we developed and characterized a humanized mouse model which is null for mouse FcRn and mouse albumin, but is transgenic for, and expressing functional human FcRn. Published data clearly demonstrate that upon injection of human albumin into this model animal that it accurately recapitulates human albumin FcRn dependent serum recycling, with human albumin now having a half-life ~24 days, closely mimicking that observed in humans. In this practical review we briefly review this model and outline its use for pharmacokinetic studies of human albumin. PMID:27150087

  12. γ-Secretase inhibition promotes fibrotic effects of albumin in proximal tubular epithelial cells

    PubMed Central

    Slattery, C; Jang, Y; Kruger, W A; Hryciw, D H; Lee, A; Poronnik, P

    2013-01-01

    Background and Purpose Albuminuria is an important biomarker of renal dysfunction and is a major mediator of renal damage and fibrosis during kidney disease. The mechanisms underlying albumin-induced renal fibrosis remain unclear. There has been significant interest in γ-secretase activity in tubular epithelial cells in recent times; however, its potential role in albumin-induced fibrosis has not been investigated. Experimental Approach The primary aim of this study was to examine the role of γ-secretase in albumin-induced fibrotic effects in proximal tubular cells. The effects of increasing albumin concentrations on fibrosis indicators and mediators in the human HK-2 cell line were examined in the presence and absence of a γ-secretase inhibitor, compound E. Key Results Treatment with albumin resulted in a number of pro-fibrotic effects, including up-regulation of fibronectin, TGF-β1 and the EGF-R. Interestingly, similar effects were observed in response to treatment with the γ-secretase inhibitor, compound E. Co-treatment of cells with albumin and an EGF-R inhibitor, AG-1478, resulted in significant inhibition of the observed pro-fibrotic effects, suggesting a major role for the EGF-R in albumin-induced fibrotic events. Albumin-induced effects on the EGF-R appeared to be mediated through inhibition of γ-secretase activity and were dependent on ERK-MAPK signalling. Conclusions and Implications These results provide novel insights into the mechanisms of albumin-induced fibrotic effects in tubular epithelial cells, suggesting important roles for the γ-secretase and the EGF-R. These results suggest that the proposed use of γ-secretase inhibitors as anti-fibrotic agents requires further investigation. PMID:23594166

  13. Shank2 Regulates Renal Albumin Endocytosis

    PubMed Central

    Dobrinskikh, Evgenia; Lewis, Linda; Doctor, R Brian; Okamura, Kayo; Lee, Min Goo; Altmann, Christopher; Faubel, Sarah; Kopp, Jeffrey B; Blaine, Judith

    2015-01-01

    Albuminuria is a strong and independent predictor of kidney disease progression but the mechanisms of albumin handling by the kidney remain to be fully defined. Previous studies have shown that podocytes endocytose albumin. Here we demonstrate that Shank2, a large scaffolding protein originally identified at the neuronal postsynaptic density, is expressed in podocytes in vivo and in vitro and plays an important role in albumin endocytosis in podocytes. Knockdown of Shank2 in cultured human podocytes decreased albumin uptake, but the decrease was not statistically significant likely due to residual Shank2 still present in the knockdown podocytes. Complete knockout of Shank2 in podocytes significantly diminished albumin uptake in vitro. Shank2 knockout mice develop proteinuria by 8 weeks of age. To examine albumin handling in vivo in wild-type and Shank2 knockout mice we used multiphoton intravital imaging. While FITC-labeled albumin was rapidly seen in the renal tubules of wild-type mice after injection, little albumin was seen in the tubules of Shank2 knockout mice indicating dysregulated renal albumin trafficking in the Shank2 knockouts. We have previously found that caveolin-1 is required for albumin endocytosis in cultured podocytes. Shank2 knockout mice had significantly decreased expression and altered localization of caveolin-1 in podocytes suggesting that disruption of albumin endocytosis in Shank2 knockouts is mediated via caveolin-1. In summary, we have identified Shank2 as another component of the albumin endocytic pathway in podocytes. PMID:26333830

  14. Exact Solutions of the 5d Space-Time Universe and Their Implications

    NASA Astrophysics Data System (ADS)

    Fukui, Takao

    2008-09-01

    What can the exact solutions of the 5D STM Universe imply when they are compared to the field equations of a Corrected Metric Tensor Universe? The comparison implies the possibility of clarifying the meaning of the cosmological term.

  15. Implications of solution chemistry effects: Direction-specific restraints on the step kinetics of calcite growth

    NASA Astrophysics Data System (ADS)

    Hong, Mina; Teng, H. Henry

    2014-09-01

    Classical crystallization models successfully depict the dependence of growth kinetics on thermodynamic driving force but cannot predict the roles of solution chemistry. Yet, it has become increasingly clear that crystal growth rate at fixed supersaturations depends on pH, ionic strength, and the relative abundance of cations and anions in the parent solutions. We conducted experiments to isolate the effect of individual solution-chemistry parameters on calcite step growth kinetics. Our results revealed a distinct correlation between step velocity and pH in acute and obtuse directions and a simultaneous trend change at pH ∼9.5. Step speeds varied with solution stoichiometry, and each direction reached its maximal rate at a different [Ca]/[CO32-] value. In addition, the solution cation/anion at which maximal step speed occurred appeared to be pH dependent as well. Limited effect of ionic strength on step growth was observed in the obtuse direction at low background electrolyte concentrations, but no obvious change was found for growth at the acute side. We proposed a growth model based upon independent incorporation of cations and anions and interpreted these observations as: (1) solute constituents enter kinks through direct solution diffusion at obtuse steps but surface diffusion at acute steps; (2) growth is limited by Ca2+ dehydration at the obtuse side, but by surface adsorption and reorientation and rearrangement of CO32- in the acute direction; and (3) background electrolyte (NaCl in our study) competes with solutes for surface sites at more easily accessible kinks.

  16. Perceptions of injury causes and solutions in a Johannesburg township: implications for prevention.

    PubMed

    Butchart, A; Kruger, J; Lekoba, R

    2000-02-01

    As with other diseases, citizen perceptions of injury causes and solutions are important determinants of their response to the problem. This study explores qualitative responses to questions about the causes and solutions for injuries due to violence, transport, and unintentional burns, falls and other causes from 1,075 residents in six neighbourhoods of a low-income area in Johannesburg, South Africa. These included council houses, council apartment blocks and informal settlements. Data were analysed using content analytic procedures. Perceived causes of injury varied sharply between neighbourhoods. Violence was seen as an outcome of unemployment, socialisation, drug abuse and drug dealing in the formal housing areas, while in the informal settlements it was attributed to unemployment, poor housing and environmental conditions, and excessive alcohol consumption. In the formal housing areas, suggested solutions for violence emphasised increased policing and other repressive measures that contradicted the attribution of causes to environmental factors. In the informal areas, solutions were more congruent with perceived causes, emphasising housing development, education and employment. Perceived causes and solutions for transport injuries reflected the specific context of each neighbourhood, and indicated strong support for the implementation of environmental modifications to reduce the speed of motor vehicles and thus the number of pedestrian injuries. Where perceived causes and solutions for violence and transport-related injuries were located beyond the community in the broader environment, unintentional injuries due to other causes were seen as more in the sphere of potential personal control, except in the informal areas where electrification and formal housing provision were the most commonly suggested solutions. Popular constructions of the causes and solutions for major categories of injury are important in shaping injury prevention responses, and their

  17. Enhanced agglutination reaction of ABO subgroups by gold nanoparticle solution: implication for identification of ABO subgroups.

    PubMed

    Ammaranond, P; Sriyarak, J; Saejong, S; Deesin, P; Seereemaspun, A; Rojanathanes, R

    2011-12-01

    Although the ABO blood group is the most significant in blood group system in human, other subgroups system is also important to be concerned in blood banking laboratory. ABO subgroups have weak antigen potency on red blood cell. In some cases, they could not been detected by cell grouping and serum grouping methods. This may lead to misinterpretation of ABO typing which will cause serious problems for transfusion and transplantation. Gold nanoparticle solution can increase the agglutination reaction of ABO typing. Thus far, the investigation of ABO blood group system has been performed using gold nanoparticle solution. Samples were tested comparing between with and without gold nanoparticle solution. After reading the agglutination reaction, supernatants were collected and measured at the optical density at 760 nm by spectrophotometer. The optical density of 2-5% cell suspension and monoclonal antibody was higher than in the tube of 2-5% cell suspension, monoclonal antibody and gold nanoparticle solution. By adding the gold nanoparticle solution, the agglutination reaction was increased ranging from 7.0-37.7% (median 15.0%) for ABO grouping system whereas 12.1-50.9% (median 23.4%) was observed in ABO subgroups. It could decrease the chance of misinterpretation by 33.3%. By using gold nanoparticle solution might be the alternative way for investigation of weak antigen potency on red blood cell. PMID:22416584

  18. Automated calibration of a stream solute transport model: Implications for interpretation of biogeochemical parameters

    USGS Publications Warehouse

    Scott, D.T.; Gooseff, M.N.; Bencala, K.E.; Runkel, R.L.

    2003-01-01

    The hydrologic processes of advection, dispersion, and transient storage are the primary physical mechanisms affecting solute transport in streams. The estimation of parameters for a conservative solute transport model is an essential step to characterize transient storage and other physical features that cannot be directly measured, and often is a preliminary step in the study of reactive solutes. Our study used inverse modeling to estimate parameters of the transient storage model OTIS (One dimensional Transport with Inflow and Storage). Observations from a tracer injection experiment performed on Uvas Creek, California, USA, are used to illustrate the application of automated solute transport model calibration to conservative and nonconservative stream solute transport. A computer code for universal inverse modeling (UCODE) is used for the calibrations. Results of this procedure are compared with a previous study that used a trial-and-error parameter estimation approach. The results demonstrated 1) importance of the proper estimation of discharge and lateral inflow within the stream system; 2) that although the fit of the observations is not much better when transient storage is invoked, a more randomly distributed set of residuals resulted (suggesting non-systematic error), indicating that transient storage is occurring; 3) that inclusion of transient storage for a reactive solute (Sr2+) provided a better fit to the observations, highlighting the importance of robust model parameterization; and 4) that applying an automated calibration inverse modeling estimation approach resulted in a comprehensive understanding of the model results and the limitation of input data.

  19. Characterization of Th carbonate solutions using XAS and implications for thermodynamic modeling

    SciTech Connect

    Hess, N.J.; Felmy, A.R.; Rai, D.; Conradson, S.D.

    1997-12-31

    The chemical behavior of actinide elements in tank solutions, in soil, and in groundwater is dependent upon the chemical species that form when aqueous solutions come in contact with the actinide compounds. In particular the chemical speciation of the reduced actinide oxidation states (III and IV) are important, for example, to DOE waste tank processing and, more generally, to nuclear waste disposal issues. Predicting the solubility of the actinides in these solutions requires identification of the strong aqueous complexes, such as carbonates and organic chelating agents, that can form in aqueous solution. Previous speciation work has often relied on indirect techniques such as potentiometric titrations or solubility measurements. Recent XAS experiments determine directly the speciation of the Th carbonato species of seven solutions under a range of carbonate concentrations and pH conditions. The presence of the pentacarbonato complex is confirmed and the complex`s stability at low carbonate concentrations is determined. These experimental results support a proposed thermodynamic model that describes the solubility of Th(IV) hydrous oxide in the aqueous Na{sup +}-HCO{sub 3}{sup {minus}}-CO{sub 3}{sup 2{minus}}-OH{sup {minus}}-ClO{sub 4}{sup {minus}}-H{sub 2}O system extending to high concentrations at 25 C. This model is relatively simple in that only two aqueous species are included Th(OH){sub 3}CO{sub 3}{sup {minus}} and Th(CO{sub 3}){sub 5}{sup 6{minus}}.

  20. Redox activity distinguishes solid-state electron transport from solution-based electron transfer in a natural and artificial protein: cytochrome C and hemin-doped human serum albumin.

    PubMed

    Amdursky, Nadav; Ferber, Doron; Pecht, Israel; Sheves, Mordechai; Cahen, David

    2013-10-28

    Integrating proteins in molecular electronic devices requires control over their solid-state electronic transport behavior. Unlike "traditional" electron transfer (ET) measurements of proteins that involve liquid environments and a redox cycle, no redox cofactor is needed for solid-state electron transport (ETp) across the protein. Here we show the fundamental difference between these two approaches by macroscopic area measurements, which allow measuring ETp temperature dependence down to cryogenic temperatures, via cytochrome C (Cyt C), an ET protein with a heme (Fe-porphyrin) prosthetic group as a redox centre. We compare the ETp to electrochemical ET measurements, and do so also for the protein without the Fe (with metal-free porphyrin) and without porphyrin. As removing the porphyrin irreversibly alters the protein's conformation, we repeat these measurements with human serum albumin (HSA), 'doped' (by non-covalent binding) with a single hemin equivalent, i.e., these natural and artificial proteins share a common prosthetic group. ETp via Cyt C and HSA-hemin are very similar in terms of current magnitude and temperature dependence, which suggests similar ETp mechanisms via these two systems, thermally activated hopping (with ~0.1 eV activation energy) >190 K and tunneling by superexchange <190 K. Also, ET rates to and from the Fe redox centres (Fe(2+) <=> Fe(3+) + e(-)), measured by electrochemistry of HSA-hemin are only 4 times lower than those for Cyt C. However, while removing the Fe redox centre from the porphyrin ring markedly affects the ET rate, it hardly changes the ETp currents through these proteins, while removing the macrocycle (from HSA, which retains its conformation) significantly reduces ETp efficiency. These results show that solid-state ETp across proteins does not require the presence of a redox cofactor, and that while for ET the Fe ion is the main electron mediator, for ETp the porphyrin ring has this function. PMID:24008341

  1. Correlating polymer solution conformation and thin film nanostructure: Implications for BHJ processing

    NASA Astrophysics Data System (ADS)

    Dattani, Rajeev; Nedoma, Alisyn; Stingelin, Natalie; Nelson, Jenny; Cabral, Joao

    2013-03-01

    We study the solution properties of polymer-fullerene mixtures by a combination of dynamic light scattering, viscometry, small angle neutron scattering and microscopy. Specifically, the kinetics of polymer conformation (Rg and Rh) and interaction changes are mapped as function of polymer-particle concentration, overall concentration in solution and age. A model system of polystyrene and C60 fullerene was selected for this study, in addition to the P3HT/PCBM pair, which is currently explored in photovoltaic applications. The solution properties show a clear correlation to the resulting thin film nanostructured composite morphology. Our future work will further link it to bulk heterojunction solar cell performance. EPSRC and Plastic Electronics DTC

  2. Ligation activity of fragmented ribozymes in frozen solution: implications for the RNA world

    PubMed Central

    Vlassov, Alexander V.; Johnston, Brian H.; Landweber, Laura F.; Kazakov, Sergei A.

    2004-01-01

    A vexing difficulty of the RNA world hypothesis is how RNA molecules of significant complexity could ever have evolved given their susceptibility to degradation. One way degradation might have been reduced is through low temperature. Here we report that truncated and fragmented derivatives of the hairpin ribozyme can catalyze ligation of a wide variety of RNA molecules to a given sequence in frozen solution despite having little or no activity under standard solution conditions. These results suggest that complex RNAs could have evolved in freezing environments on the early earth and perhaps elsewhere. PMID:15161960

  3. Contextual approach to technology assessment: Implications for one-factor fix solutions to complex social problems

    NASA Technical Reports Server (NTRS)

    Mayo, L. H.

    1975-01-01

    The contextual approach is discussed which undertakes to demonstrate that technology assessment assists in the identification of the full range of implications of taking a particular action and facilitates the consideration of alternative means by which the total affected social problem context might be changed by available project options. It is found that the social impacts of an application on participants, institutions, processes, and social interests, and the accompanying interactions may not only induce modifications in the problem contest delineated for examination with respect to the design, operations, regulation, and use of the posited application, but also affect related social problem contexts.

  4. Reentrant condensation of lysozyme: Implications for studying dynamics of lysozyme in aqueous solutions of lithium chloride

    SciTech Connect

    Mamontov, Eugene; O'Neill, Hugh Michael

    2014-01-01

    Recent studies have outlined the use of eutectic solution of lithium chloride in water to study microscopic dynamics of lysozyme in an aqueous solvent that is remarkably similar to pure water in many respects, yet allows experiments over a wide temperature range without the solvent crystallization. The eutectic point in (H2O)R(LiCl) system corresponds to R 7.3, and it is of interest to investigate whether less concentrated aqueous solutions of LiCl could be employed in low-temperature studies of a solvated protein. We have investigated a range of concentrations of lysozyme and LiCl in aqueous solutions to identify systems that do not show phase separation and avoid solvent crystallization on cooling down. Compared to the lysozyme concentration in solution, the concentration of LiCl in the aqueous solvent plays the major role in determining systems suitable for low-temperature studies. We have observed interesting and rich phase behavior reminiscent of reentrant condensation of proteins.

  5. PROPERTY CHANGES IN AQUEOUS SOLUTIONS DUE TO SURFACTANT TREATMENT OF PCE: IMPLICATIONS TO GEOPHYSICAL MEASUREMENTS

    EPA Science Inventory

    Select physicochemical properties of aqueous solutions composed of surfactants, dye, and

    perchloroethylene (PCE) were evaluated through a response surface quadratic design

    model of experiment. Nine surfactants, which are conventionally used in the

    remediation...

  6. Solution-Focused Brief Counseling: Guidelines, Considerations, and Implications for School Psychologists

    ERIC Educational Resources Information Center

    Jones, Camille N.; Hart, Shelley R.; Jimerson, Shane R.; Dowdy, Erin; Earhart, James, Jr.; Renshaw, Tyler L.; Eklund, Katie; Anderson, Doug

    2009-01-01

    The increasing emphasis on school-based mental health services is likely to increase the demand for school psychologists to provide counseling with students. Providing counseling in the school context can be challenging, especially given time constraints and limited number of sessions. Solution-focused brief counseling (SFBC) is an approach that…

  7. Raman microspectroscopy of nanodiamond-induced structural changes in albumin.

    PubMed

    Svetlakova, Anastasiya S; Brandt, Nikolay N; Priezzhev, Alexander V; Chikishev, Andrey Yu

    2015-04-01

    Nanodiamonds (NDs) are promising agents for theranostic applications due to reported low toxicity and high biocompatibility, which is still being extensively tested on cellular, tissue, and organism levels. It is presumed that for experimental and future clinical applications, NDs will be administered into the organism via the blood circulation system. In this regard, the interaction of NDs with blood components needs to be thoroughly studied. We studied the interaction of carboxylated NDs (cNDs) with albumin, one of the major proteins of blood plasma. After 2-h long in vitro incubation in an aqueous solution of the protein, 100-nm cNDs were dried and the dry samples were studied with the aid of Raman microspectroscopy. The spectroscopic data indicate significant conformational changes that can be due to cND–protein interaction. A possible decrease in the functional activity of albumin related to the conformational changes must be taken into account in the in vivo applications. PMID:25901656

  8. Total Protein and Albumin/Globulin Ratio Test

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Total Protein and Albumin/Globulin (A/G) Ratio Share this ... Globulin Ratio; A/G Ratio Formal name: Total Protein; Albumin to Globulin Ratio Related tests: Albumin ; Liver ...

  9. Is albumin administration in the acutely ill associated with increased mortality? Results of the SOAP study

    PubMed Central

    Vincent, Jean-Louis; Sakr, Yasser; Reinhart, Konrad; Sprung, Charles L; Gerlach, Herwig; Ranieri, V Marco

    2005-01-01

    Introduction Albumin administration in the critically ill has been the subject of some controversy. We investigated the use of albumin solutions in European intensive care units (ICUs) and its relationship to outcome. Methods In a cohort, multicenter, observational study, all patients admitted to one of the participating ICUs between 1 May and 15 May 2002 were followed up until death, hospital discharge, or for 60 days. Patients were classified according to whether or not they received albumin at any time during their ICU stay. Results Of 3,147 admitted patients, 354 (11.2%) received albumin and 2,793 (88.8%) did not. Patients who received albumin were more likely to have cancer or liver cirrhosis, to be surgical admissions, and to have sepsis. They had a longer length of ICU stay and a higher mortality rate, but were also more severely ill, as manifested by higher simplified acute physiology score (SAPS) II and sequential organ failure assessment (SOFA) scores than the other patients. A Cox proportional hazard model indicated that albumin administration was significantly associated with decreased 30-day survival. Moreover, in 339 pairs matched according to a propensity score, ICU and hospital mortality rates were higher in the patients who had received albumin than in those who had not (34.8 versus 20.9% and 41.3 versus 27.7%, respectively, both p < 0.001). Conclusion Albumin administration was associated with decreased survival in this population of acutely ill patients. Further prospective randomized controlled trials are needed to examine the effects of albumin administration in sub-groups of acutely ill patients. PMID:16356223

  10. Ultrasonic frequency analysis for estimating pH in albumin-rich biofluids.

    PubMed

    Rackov, Andrien A; Burns, David H

    2016-03-01

    Ultrasound is known as a non-invasive imaging modality capable of propagating through highly scattering media such as tissue, blood, and other biological fluids, yet currently provides little chemical information. We have developed a straightforward and rapid methodology for estimating pH in albumin-rich biofluids based on analysis of ultrasonic frequencies. Albumin is the most abundant protein in serum and undergoes conformational changes with pH. It was shown that when ultrasound propagated through albumin solutions, the attenuation of collected ultrasound signals increased with pH. By measuring the ultrasound frequency spectra at several albumin concentrations and pH values, the pH of the solutions could be determined by multilinear regression. Differences in absolute protein content contributed to signal differences in the frequency profiles and were minimized through normalization of each spectrum by the sum of all its frequency intensities. This strategy was applied to human serum samples from multiple donors, for which a multilinear regression model was developed with a coefficient of determination (R(2)) of 0.93 and a standard error of estimate (SEE) of 0.08 pH units. The use of albumin as a pH indicator opens the doors for estimations in other albumin-rich media, such as amniotic fluid and cerebrospinal fluid. PMID:26717815

  11. Cisplatin loaded albumin mesospheres for lung cancer treatment

    PubMed Central

    Lee, Hung-Yen; Mohammed, Kamal A; Goldberg, Eugene P; Kaye, Frederic; Nasreen, Najmunnisa

    2015-01-01

    The low solubility of cisplatin in aqueous solution limits the treatment effectiveness and the application of cisplatin in various kinds of drug-eluting devices. Although cisplatin has a high solubility in Dimethyl sulfoxide (DMSO), the toxicity of cisplatin can be greatly reduced while dissolved in DMSO. In this study, the solid powder of cisplatin-loaded albumin mesospheres (CDDP/DMSO-AMS), in a size range of 1 to 10 µm, were post-loaded with cisplatin and showed high cisplatin content (16% w/w) and effective cytotoxicity to lung cancer cells. Cisplatin were efficiently absorbed into the albumin mesospheres (AMS) in DMSO and, most importantly, the toxicity of cisplatin was remained at 100% after the loading process. This CDDP/DMSO-AMS was designed for the intratumoral injection through the bronchoscopic catheter or dry powder inhalation (DPI) due to its high stability in air or in solution. This CDDP/DMSO-AMS showed a fast cisplatin release within 24 hours. In the in vitro study, CDDP/DMSO-AMS showed high effectiveness on killing the lung cancer cells including the non-small cell lung cancer (NCL-H23 and A549), malignant mesothelioma (CRL-2081) and the mouse lung carcinoma (Lewis lung carcinoma) cell lines. The albumin based mesospheres provide an ideal loading matrix for cisplatin and other metal-based drugs due to the high swelling degree and fast uptake rate in the organic solvents with high polarity. In addition, to investigate the effects of polysaccharides, such as chitosan and chondroitin, on enhancing loading efficiency and lasting cytotoxicity of cisplatin, the polysaccharide-modified albumin mesospheres were synthesized and loaded with cisplatin in this study. PMID:25973300

  12. Cisplatin loaded albumin mesospheres for lung cancer treatment.

    PubMed

    Lee, Hung-Yen; Mohammed, Kamal A; Goldberg, Eugene P; Kaye, Frederic; Nasreen, Najmunnisa

    2015-01-01

    The low solubility of cisplatin in aqueous solution limits the treatment effectiveness and the application of cisplatin in various kinds of drug-eluting devices. Although cisplatin has a high solubility in Dimethyl sulfoxide (DMSO), the toxicity of cisplatin can be greatly reduced while dissolved in DMSO. In this study, the solid powder of cisplatin-loaded albumin mesospheres (CDDP/DMSO-AMS), in a size range of 1 to 10 µm, were post-loaded with cisplatin and showed high cisplatin content (16% w/w) and effective cytotoxicity to lung cancer cells. Cisplatin were efficiently absorbed into the albumin mesospheres (AMS) in DMSO and, most importantly, the toxicity of cisplatin was remained at 100% after the loading process. This CDDP/DMSO-AMS was designed for the intratumoral injection through the bronchoscopic catheter or dry powder inhalation (DPI) due to its high stability in air or in solution. This CDDP/DMSO-AMS showed a fast cisplatin release within 24 hours. In the in vitro study, CDDP/DMSO-AMS showed high effectiveness on killing the lung cancer cells including the non-small cell lung cancer (NCL-H23 and A549), malignant mesothelioma (CRL-2081) and the mouse lung carcinoma (Lewis lung carcinoma) cell lines. The albumin based mesospheres provide an ideal loading matrix for cisplatin and other metal-based drugs due to the high swelling degree and fast uptake rate in the organic solvents with high polarity. In addition, to investigate the effects of polysaccharides, such as chitosan and chondroitin, on enhancing loading efficiency and lasting cytotoxicity of cisplatin, the polysaccharide-modified albumin mesospheres were synthesized and loaded with cisplatin in this study. PMID:25973300

  13. Glycated Serum Albumin and AGE Receptors.

    PubMed

    Vetter, Stefan W

    2015-01-01

    In vivo modification of proteins by molecules with reactive carbonyl groups leads to intermediate and advanced glycation end products (AGE). Glucose is a significant glycation reagent due to its high physiological concentration and poorly controlled diabetics show increased albumin glycation. Increased levels of glycated and AGE-modified albumin have been linked to diabetic complications, neurodegeneration, and vascular disease. This review discusses glycated albumin formation, structural consequences of albumin glycation on drug binding, removal of circulating AGE by several scavenger receptors, as well as AGE-induced proinflammatory signaling through activation of the receptor for AGE. Analytical methods for quantitative detection of protein glycation and AGE formation are compared. Finally, the use of glycated albumin as a novel clinical marker to monitor glycemic control is discussed and compared to glycated hemoglobin (HbA1c) as long-term indicator of glycemic status. PMID:26471084

  14. Tolerability of Oral Xylitol Solution in Young Children: Implications for Otitis Media Prophylaxis

    PubMed Central

    Vernacchio, Louis; Vezina, Richard M.; Mitchell, Allen A.

    2007-01-01

    Objective. Xylitol, given as two grams orally five times-a-day, significantly reduces the incidence of acute otitis media (AOM) in children. A less frequent dosing schedule, if tolerable and efficacious, would promote the more widespread use of this treatment. We sought to determine the tolerability and acceptability in young children of oral xylitol solution at doses of 5 grams three times-a-day (TID) and 7.5 grams once daily (QD). Methods. The study was a three-month randomized placebo-controlled trial of the tolerability and acceptability of oral xylitol solution in 120 children 6-36 months of age performed in the SCOR Network. Results. Study withdrawals and unscheduled medical visits for gastrointestinal complaints did not differ significantly among the study groups. The proportions of subjects in the xylitol TID group who experienced excessive gas or diarrhea at months one, two, and three were 22.7%, 10.0%, and 14.3%, respectively, and in the xylitol QD group were 27.3%, 17.4%, and 14.3%, respectively, and these did not differ from the placebo groups. The proportions who accepted the study solution easily or with only minor difficulty at one, two, and three months in the xylitol TID group were 77.3%, 90.0%, and 90.5% and in the xylitol QD group, 77.3%, 82.6%, and 90.5%, respectively. Conclusions. Oral xylitol solution at dosages of 5 grams TID and 7.5 grams QD is well-tolerated by young children. Given the potential for xylitol as a safe, inexpensive option for AOM prophylaxis, clinical trials using these dosages of xylitol can be conducted. PMID:17097152

  15. In vivo biocompatibility, clearance, and biodistribution of albumin vehicles for pulmonary drug delivery

    PubMed Central

    Woods, A.; Patel, A.; Spina, D.; Riffo-Vasquez, Y.; Babin-Morgan, A.; de Rosales, R.T.M.; Sunassee, K.; Clark, S.; Collins, H.; Bruce, K.; Dailey, L.A.; Forbes, B.

    2015-01-01

    The development of clinically acceptable albumin-based nanoparticle formulations for use in pulmonary drug delivery has been hindered by concerns about the toxicity of nanomaterials in the lungs combined with a lack of information on albumin nanoparticle clearance kinetics and biodistribution. In this study, the in vivo biocompatibility of albumin nanoparticles was investigated following a single administration of 2, 20, and 390 μg/mouse, showing no inflammatory response (TNF-α and IL-6, cellular infiltration and protein concentration) compared to vehicle controls at the two lower doses, but elevated mononucleocytes and a mild inflammatory effect at the highest dose tested. The biodistribution and clearance of 111In labelled albumin solution and nanoparticles over 48 h following a single pulmonary administration to mice was investigated by single photon emission computed tomography and X-ray computed tomography imaging and terminal biodistribution studies. 111In labelled albumin nanoparticles were cleared more slowly from the mouse lung than 111In albumin solution (64.1 ± 8.5% vs 40.6 ± 3.3% at t = 48 h, respectively), with significantly higher (P < 0.001) levels of albumin nanoparticle-associated radioactivity located within the lung tissue (23.3 ± 4.7%) compared to the lung fluid (16.1 ± 4.4%). Low amounts of 111In activity were detected in the liver, kidneys, and intestine at time points > 24 h indicating that small amounts of activity were cleared from the lungs both by translocation across the lung mucosal barrier, as well as mucociliary clearance. This study provides important information on the fate of albumin vehicles in the lungs, which may be used to direct future formulation design of inhaled nanomedicines. PMID:25980621

  16. Serum albumin binding of structurally diverse neutral organic compounds: data and models.

    PubMed

    Endo, Satoshi; Goss, Kai-Uwe

    2011-12-19

    Binding to serum albumin has a strong influence on freely dissolved, unbound concentrations of chemicals in vivo and in vitro. For neutral organic solutes, previous studies have suggested a log-log correlation between the albumin-water partition coefficient and the octanol-water partition coefficient (K(ow)) and postulated highly nonspecific binding that is mechanistically analogous to dissolution into solvents. These relationships and concepts were further explored in this study. Bovine serum albumin (BSA)-water partition coefficients (K(BSA/w)) were measured for 83 structurally diverse neutral organic chemicals in consistent experimental conditions. The correlation between log K(BSA/w) and log K(ow) was moderate, with R(2) = 0.76 and SD = 0.43. The log K(BSA/w) of low-polarity compounds including a series of chlorobenzenes and polycyclic aromatic hydrocarbons increased with log K(ow) linearly up to log K(ow) = 4-5, but then the linear relationship apparently broke off, and the increase became gradual. The fitting of polyparameter linear free energy relationship models with five solute descriptors was just comparable to that of the log K(ow) model (R(2) = 0.78-0.79, SD = 0.41-0.42); the relatively high SD obtained suggests that solvent dissolution models are not capable of modeling albumin binding accurately. A size limitation of the binding site(s) of albumin is suggested as a possible reason for the high SD. An equilibrium distribution model indicates that serum albumin generally has high contributions to the binding in the serum of polar compounds and relatively small low-polarity compounds, whereas albumin binding for large low-polarity compounds is outcompeted by the strong partitioning into lipids due to low relative affinity of albumin for these compounds. PMID:22070391

  17. Investigation of Bovine Serum Albumin (BSA) Attachment onto Self-Assembled Monolayers (SAMs) Using Combinatorial Quartz Crystal Microbalance with Dissipation (QCM-D) and Spectroscopic Ellipsometry (SE)

    PubMed Central

    Phan, Hanh T. M.; Bartelt-Hunt, Shannon; Rodenhausen, Keith B.; Schubert, Mathias; Bartz, Jason C.

    2015-01-01

    Understanding protein adsorption kinetics to surfaces is of importance for various environmental and biomedical applications. Adsorption of bovine serum albumin to various self-assembled monolayer surfaces including neutral and charged hydrophilic and hydrophobic surfaces was investigated using in-situ combinatorial quartz crystal microbalance with dissipation and spectroscopic ellipsometry. Adsorption of bovine serum albumin varied as a function of surface properties, bovine serum albumin concentration and pH value. Charged surfaces exhibited a greater quantity of bovine serum albumin adsorption, a larger bovine serum albumin layer thickness, and increased density of bovine serum albumin protein compared to neutral surfaces at neutral pH value. The quantity of adsorbed bovine serum albumin protein increased with increasing bovine serum albumin concentration. After equilibrium sorption was reached at pH 7.0, desorption of bovine serum albumin occurred when pH was lowered to 2.0, which is below the isoelectric point of bovine serum albumin. Our data provide further evidence that combinatorial quartz crystal microbalance with dissipation and spectroscopic ellipsometry is a sensitive analytical tool to evaluate attachment and detachment of adsorbed proteins in systems with environmental implications. PMID:26505481

  18. Protease Inhibition by Oleic Acid Transfer From Chronic Wound Dressings to Albumin

    SciTech Connect

    Edwards, J. V.; Howley, Phyllis; Davis, Rachel M.; Mashchak, Andrew D.; Goheen, Steven C.

    2007-08-01

    High elastase and cathepsin G activities have been observed in chronic wounds. These levels can inhibit healing through degradation of growth factors, cytokines, and extracellular matrix proteins. Oleic acid (18:1) is a non-toxic elastase inhibitor with some potential for redressing the imbalance of elastase activity found in chronic wounds. Cotton wound dressing material was characterized as a transfer carrier for affinity uptake of 18:1 by albumin under conditions mimicking chronic wounds. 18:1-treated cotton was examined for its ability to bind and release the fatty acid in the presence of albumin. The mechanism of 18:1 uptake from cotton and binding by albumin was examined with both intact dressings and cotton fiber-designed chromatography. Raman spectra of the albumin-18:1 complexes under liquid-liquid equilibrium conditions revealed fully saturated albumin-18:1 complexes with a 1:1 weight ratio of albumin:18:1. Cotton chromatography under liquid-solid equilibrium conditions revealed oleic acid transfer from cotton to albumin at 27 mole equivalents of 18:1 per mole albumin. Cotton was contrasted with hydrogel, and hydrocolloid wound dressing for its comparative ability to lower elastase activity. Each dressing material evaluated was found to release 18:1 in the presence of albumin with significant inhibition of elastase activity. The 18:1-formulated wound dressings lowered elastase activity in a dose dependent manner in the order cotton gauze > hydrogel > hydrocolloid. In contrast the cationic serine protease Cathepsin G was inihibited by 18:1 within a narrow range of 18:1-cotton formulations. Four per cent Albumin solutions were most effective in binding cotton bound-18:1. However, 2% albumin was sufficient to transfer quantities of 18:1 necessary to achieve a significant elastase-lowering effect. Formulations with 128 mg 18:1/g cotton gauze had equivalent elastase lowering with 1 - 4% albumin. 18:1 bound to cotton wound dressings may have promise in the

  19. Water movement and solute transport in permafrost wetlands: implications for inorganic carbon cycling

    NASA Astrophysics Data System (ADS)

    Jessen, Søren; Dahl Holmslykke, Hanne; Rasmussen, Kristine; Richardt, Niels; Engelund Holm, Peter

    2014-05-01

    Carbon dioxide emissions from thawing permafrost wetlands are an expected consequence of global warming. Addressing the pathways by which carbon is emitted, we investigated the hydrological and geochemical controls on the pore water chemistry of a permafrost wetland, with a shallow geological sequence comprising loam overlain by sphagnum peat, in Ilulissat, Greenland. A 400 m transect parallel to the general flow direction was established, along which water table measurements and slug tests were conducted, and the active layer thickness recorded (typically ~0.5 m). Also, in three detailed profiles along the transect, the vertical distributions of stable isotopes of water and major ion chemistry were investigated, by analysis of active layer pore water and water of melted core sections of permafrost. Concentrations of chloride (0.3-0.4 mM) did not show variation with depth, dismissing solute movement by ion freeze-out during fall freeze-up as a main control on the water chemistry. In addition, the observed vertical δ18O distribution did not to any extent conform to modelled Rayleigh distillation curves for the preferential inclusion of H218O into ice, which could be a scenario for fall freeze-up. The δ18O data therefore suggests either a rapid freeze-up or a simultaneous phase transition at all depths of the active layer, which in either case also would minimize potential ion freeze-out effects. Nevertheless, concentrations of major ions generally increased with depth. A conceptual model for water and solute transport was therefore established, according to which solutes are mobilized by weathering reactions in the loam and then transported upwards to the peat by diffusion. In the peat, lateral advective solute transport dominates. We applied the model to observed profiles of Ca, Mg, HCO3 and the partial CO2 pressure (PCO2). Concentrations of Ca, Mg and HCO3 increased with depth, reaching ~2 mM, ~2 mM and ~8 meq/L at the bottom of the active layer. Pore water at

  20. Experimental calibration of Mg isotope fractionation between dolomite and aqueous solution and its geological implications

    NASA Astrophysics Data System (ADS)

    Li, Weiqiang; Beard, Brian L.; Li, Chengxiang; Xu, Huifang; Johnson, Clark M.

    2015-05-01

    Hydrothermal experiments at 220, 160, and 130 °C were performed to calibrate the Mg isotope fractionation factor between dolomite and aqueous Mg. Hydrothermal experiments included synthesis of dolomite using different starting materials, as well as exchange experiments that used poorly-ordered proto-dolomite. The morphology of synthesized dolomite was dependent on starting mineralogy, suggesting that dolomite was synthesized by different pathways. Hydrothermally synthesized dolomite was initially fine-grained disordered or poorly-ordered dolomite that, with time, recrystallized to coarser-grained ordered dolomite. Isotopic exchange was monitored using 87Sr/86Sr ratios and 25Mg tracers, and these indicated near-complete isotope exchange between dolomite and aqueous solutions at the end of most hydrothermal experiments. The Mg isotope fractionation factor between dolomite and aqueous solution obtained from synthesis and exchange experiments converged with time and was independent of dolomite morphology, suggesting attainment of isotopic equilibrium. Combining results from synthesis and exchange experiments, the temperature dependent Mg isotope fractionation factor for ordered dolomite is:

  1. Organics Produced by Irradiation of Frozen and Liquid HCN Solutions: Implications for Chemical Evolution Studies

    NASA Astrophysics Data System (ADS)

    Colín-García, M.; Negrón-Mendoza, A.; Ramos-Bernal, S.

    2009-04-01

    Hydrogen cyanide (HCN), an important precursor of organic compounds, is widely present in extraterrestrial environments. HCN is also readily synthesized in prebiotic simulation experiments. To gain insight into the radiation chemistry of one of the most important and highly versatile constituents of cometary ices, we examined the behavior of over-irradiated frozen and liquid HCN solutions under ionizing radiation. The samples were exposed to gamma radiation at a dose range from 0 up to 419 kGy. Ultraviolet spectroscopy and gas chromatography were used to follow the process. The analyses confirmed that gamma-ray irradiation of liquid HCN solutions generates several organic products. Many of them are essential to life; we verified the presence of carboxylic acids (some of them members of the Krebs cycle) as well as free amino acids and urea. These are the first studies to reveal the presence of these compounds in experiments performed at low temperatures and bulk irradiation. Organic material was produced even at low temperatures and low radiation doses. This work strongly supports the presumption that, as a parent molecule, HCN played a central essential role in the process of chemical evolution on early Earth, comets, and other extraterrestrial environments.

  2. Albumin microspheres for oral delivery of iron.

    PubMed

    Shivakumar, H N; Vaka, Siva Ram Kiran; Murthy, S Narasimha

    2010-01-01

    Bovine serum albumin (BSA) microspheres of ferric pyrophosphate (FPP) intended for passive targeting to the Peyer's patches has been proposed for oral iron supplementation. Microspheres prepared by emulsification chemical cross linking method were characterized for surface topography, entrapment efficiency, particle size, particle charge and in vitro drug release. Microspheres of batch C with FPP to BSA ratio of 1:5 were found to be most suitable for targeting as they exhibited high entrapment (83.88 +/- 4.31), high monodispersity (span = 1.24 +/- 0.01), and least particle size (d(vm) = 4.40 +/- 0.01). In addition the amount of iron retained in these microspheres despite exposure to simulated gastrointestinal conditions for 5 h was found to be 83.72 +/- 4.22%, the highest in the three batches. The in vivo serum iron profiles in normal rats following oral administration displayed a reduced T(max) (2 h), elevated C(max) (106.06 +/- 12.18 mug/dL) and increased AUC (0-16 h) (647.44 +/- 52.33 mug.h/dL) for these microspheres which significantly differed (P <0.05) from FPP solution indicating a higher iron repletion potential of the BSA microspheres. PMID:19635031

  3. Early albumin infusion to infants at risk for respiratory distress

    PubMed Central

    Bland, R. D.; Clarke, T. L.; Harden, L. B.; Mayer, Judith L.; Ries, J. P.; Madden, W. A.; Crast, F. W.; Coyer, W. F.; Bass, J. W.

    1973-01-01

    In a randomized prospective study, 100 high-risk infants (selected on the basis of a cord serum protein level of 4·6 g/100 ml or less, gestational age under 37 weeks, birthweight 2500 g or less, and/or arterial pH below 7·25) received 8 ml/kg of either 25% salt-poor albumin or 5% dextrose in water before the age of 2 hours. All infants were then managed supportively with warmth, appropriate oxygen supplementation, isotonic fluid infusion, and close monitoring, without further administration of colloid or hypertonic alkali solutions over the first 4 hours of life. No statistically significant difference was shown between early colloid and early dextrose-water administration for either the incidence of idiopathic respiratory distress syndrome (RDS) or the mortality of high-risk infants, suggesting no apparent advantage of albumin over simple glucose-water infusion to hypoproteinaemic newborns shortly after birth. However, among the infants of 28 weeks' gestation or less admitted to the study, 3 of 4 albumin-treated patients survived, while 5 comparable infants in the dextrose-water group died within 12 hours of birth. For the 100 infants taken together there was a significant improvement in morbidity and mortality from previous experience in the same nursery, indicating that prompt supportive care, including early fluid administration, may be instrumental in reducing the incidence and severity of RDS. PMID:4749684

  4. Comparative Study of Laterite and Bentonite Based Organoclays: Implications of Hydrophobic Compounds Remediation from Aqueous Solutions

    PubMed Central

    Nafees, Muhammad; Waseem, Amir; Khan, Abdur Rehman

    2013-01-01

    Four cost effective organoclays were synthesized, characterized, and studied for the sorption of hydrophobic compounds (edible oil/grease and hydrocarbon oil) from aqueous solutions. Organoclays were prepared by cation exchange reaction of lattice ions (present onto the surface of laterite and bentonite clay minerals) with two surfactants, hexadecyl trimethyl ammonium chloride (HDTMA-Cl) and tetradecyl trimethyl ammonium bromide (TDTMA-Br). Fourier transform infrared spectroscopy and scanning electron microscopy were used for the characterization of synthesized organoclays. It was found that the amount of surfactant loading and the nature of the surfactant molecules used in the syntheses of organoclay strongly affect the sorption capacity of the clay mineral. Further, it was found that both the laterite and bentonite based organoclays efficiently removed the edible and hydrocarbon oil content from lab prepared emulsions; however, the adsorption capacity of clay mineral was greatly influenced by the nature of hydrophobic compounds as well. PMID:24302867

  5. Comparative study of laterite and bentonite based organoclays: implications of hydrophobic compounds remediation from aqueous solutions.

    PubMed

    Nafees, Muhammad; Waseem, Amir; Khan, Abdur Rehman

    2013-01-01

    Four cost effective organoclays were synthesized, characterized, and studied for the sorption of hydrophobic compounds (edible oil/grease and hydrocarbon oil) from aqueous solutions. Organoclays were prepared by cation exchange reaction of lattice ions (present onto the surface of laterite and bentonite clay minerals) with two surfactants, hexadecyl trimethyl ammonium chloride (HDTMA-Cl) and tetradecyl trimethyl ammonium bromide (TDTMA-Br). Fourier transform infrared spectroscopy and scanning electron microscopy were used for the characterization of synthesized organoclays. It was found that the amount of surfactant loading and the nature of the surfactant molecules used in the syntheses of organoclay strongly affect the sorption capacity of the clay mineral. Further, it was found that both the laterite and bentonite based organoclays efficiently removed the edible and hydrocarbon oil content from lab prepared emulsions; however, the adsorption capacity of clay mineral was greatly influenced by the nature of hydrophobic compounds as well. PMID:24302867

  6. Human serum albumin crystals and method of preparation

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor)

    1989-01-01

    Human serum albumin (HSA) crystals are provided in the form of tetragonal plates having the space groups P42(sub 1)2, the crystals being grown to sizes in excess of 0.5 mm in two dimensions and a thickness of 0.1 mm. Growth of the crystals is carried out by a hanging drop method wherein a precipitant solution containing polyethylene glycol (PEG) and a phosphate buffer is mixed with an HSA solution, and a droplet of mixed solution is suspended over a well of precipitant solution. Crystals grow to the desired size in 3 to 7 days. Concentration of reagents, pH and other parameters are controlled within prescribed limits. The resulting crystals exhibit a size and quality such as to allow performance of x ray diffraction studies and enable the conduct of drug binding studies as well as genetic engineering studies.

  7. Hierarchical simulation of aquifer heterogeneity: implications of different simulation settings on solute-transport modeling

    NASA Astrophysics Data System (ADS)

    Comunian, Alessandro; De Micheli, Leonardo; Lazzati, Claudio; Felletti, Fabrizio; Giacobbo, Francesca; Giudici, Mauro; Bersezio, Riccardo

    2016-03-01

    The fine-scale heterogeneity of porous media affects the large-scale transport of solutes and contaminants in groundwater and it can be reproduced by means of several geostatistical simulation tools. However, including the available geological information in these tools is often cumbersome. A hierarchical simulation procedure based on a binary tree is proposed and tested on two real-world blocks of alluvial sediments, of a few cubic meters volume, that represent small-scale aquifer analogs. The procedure is implemented using the sequential indicator simulation, but it is so general that it can be adapted to various geostatistical simulation tools, improving their capability to incorporate geological information, i.e., the sedimentological and architectural characterization of heterogeneity. When compared with a standard sequential indicator approach on bi-dimensional simulations, in terms of proportions and connectivity indicators, the proposed procedure yields reliable results, closer to the reference observations. Different ensembles of three-dimensional simulations based on different hierarchical sequences are used to perform numerical experiments of conservative solute transport and to obtain ensembles of equivalent pore velocity and dispersion coefficient at the scale length of the blocks (meter). Their statistics are used to estimate the impact of the variability of the transport properties of the simulated blocks on contaminant transport modeled on bigger domains (hectometer). This is investigated with a one-dimensional transport modeling based on the Kolmogorov-Dmitriev theory of branching stochastic processes. Applying the proposed approach with diverse binary trees and different simulation settings provides a great flexibility, which is revealed by the differences in the breakthrough curves.

  8. Surface tension in situ in flooded alveolus unaltered by albumin.

    PubMed

    Kharge, Angana Banerjee; Wu, You; Perlman, Carrie E

    2014-09-01

    In the acute respiratory distress syndrome, plasma proteins in alveolar edema liquid are thought to inactivate lung surfactant and raise surface tension, T. However, plasma protein-surfactant interaction has been assessed only in vitro, during unphysiologically large surface area compression (%ΔA). Here, we investigate whether plasma proteins raise T in situ in the isolated rat lung under physiologic conditions. We flood alveoli with liquid that omits/includes plasma proteins. We ventilate the lung between transpulmonary pressures of 5 and 15 cmH2O to apply a near-maximal physiologic %ΔA, comparable to that of severe mechanical ventilation, or between 1 and 30 cmH2O, to apply a supraphysiologic %ΔA. We pause ventilation for 20 min and determine T at the meniscus that is present at the flooded alveolar mouth. We determine alveolar air pressure at the trachea, alveolar liquid phase pressure by servo-nulling pressure measurement, and meniscus radius by confocal microscopy, and we calculate T according to the Laplace relation. Over 60 ventilation cycles, application of maximal physiologic %ΔA to alveoli flooded with 4.6% albumin solution does not alter T; supraphysiologic %ΔA raise T, transiently, by 51 ± 4%. In separate experiments, we find that addition of exogenous surfactant to the alveolar liquid can, with two cycles of maximal physiologic %ΔA, reduce T by 29 ± 11% despite the presence of albumin. We interpret that supraphysiologic %ΔA likely collapses the interfacial surfactant monolayer, allowing albumin to raise T. With maximal physiologic %ΔA, the monolayer likely remains intact such that albumin, blocked from the interface, cannot interfere with native or exogenous surfactant activity. PMID:24970853

  9. Solubility of HOBr in Acidic Solution and Implications for Liberation of Halogens Via Aerosol Processing

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.; Michelsen, R. R.; Rammer, T. A.; Ashbourn, S. F. M.

    2004-01-01

    Halogen species are known to catalytically destroy ozone in several regions of the atmosphere. In addition to direct catalytic losses, bromine compounds can indirectly enhance ozone loss through coupling to other radical families. Hypobromous acid (HOBr) is a key species in the linkage of BrOx to ClOx and HOx. The aqueous- phase coupling reaction HOBr + HCI (right arrow) BrCl + H2O may provide a pathway for chlorine activation on sulfate aerosols at temperatures warmer than those required for polar stratospheric cloud formation. We have measured t h e solubility of HOBr in 45 - 70 wt% sulfuric acid solutions. Over the temperature range 201 - 252 K, HOBr is quite soluble in sulfuric acid, H* = 10(exp 4) - 10(exp 7) mol dm(exp -3) atm(exp -1). The expected inverse dependence of H* on temperature was observed, but only a weak dependence on acidity was found. The solubility of HOBr is comparable to that of HBr, indicating that equilibrium concentrations of HOBr could equal or exceed those of HBr in upper tropospheric and lower stratospheric aerosols. Despite the high solubility of HOBr, aerosol volumes are not large enough to sequester a significant fraction of inorganic bromine from the gas phase. Our measurements of HOBr uptake in aqueous sulfuric acid in the presence of other brominated gases show the evolution of gaseous products including Br2O and Br2.

  10. Analytical Solutions for Radiative Transfer: Implications for Giant Planet Formation by Disk Instability

    NASA Astrophysics Data System (ADS)

    Boss, Alan P.

    2009-03-01

    The disk instability mechanism for giant planet formation is based on the formation of clumps in a marginally gravitationally unstable protoplanetary disk, which must lose thermal energy through a combination of convection and radiative cooling if they are to survive and contract to become giant protoplanets. While there is good observational support for forming at least some giant planets by disk instability, the mechanism has become theoretically contentious, with different three-dimensional radiative hydrodynamics codes often yielding different results. Rigorous code testing is required to make further progress. Here we present two new analytical solutions for radiative transfer in spherical coordinates, suitable for testing the code employed in all of the Boss disk instability calculations. The testing shows that the Boss code radiative transfer routines do an excellent job of relaxing to and maintaining the analytical results for the radial temperature and radiative flux profiles for a spherical cloud with high or moderate optical depths, including the transition from optically thick to optically thin regions. These radial test results are independent of whether the Eddington approximation, diffusion approximation, or flux-limited diffusion approximation routines are employed. The Boss code does an equally excellent job of relaxing to and maintaining the analytical results for the vertical (θ) temperature and radiative flux profiles for a disk with a height proportional to the radial distance. These tests strongly support the disk instability mechanism for forming giant planets.

  11. Paclitaxel Albumin-stabilized Nanoparticle Formulation

    Cancer.gov

    This page contains brief information about paclitaxel albumin-stabilized nanoparticle formulation and a collection of links to more information about the use of this drug, research results, and ongoing clinical trials.

  12. Efficient solution of large-scale electromagnetic Eigenvalue problems using the implicity restarted Arnoldi method

    SciTech Connect

    White, D; Koning, J

    1999-10-21

    The authors are interested in determining the electromagnetic fields within closed perfectly conducting cavities that may contain dielectric or magnetic materials. The vector Helmholtz equation is the appropriate partial differential equation for this problem. It is well known that the electromagnetic fields in a cavity can be decomposed into distinct modes that oscillate in time at specific resonant frequencies. These modes are referred to as eigenmodes, and the frequencies of these modes are referred to as eigenfrequencies. The authors' present application is the analysis of linear accelerator components. These components may have a complex geometry; hence numerical methods are require to compute the eigenmodes and the eigenfrequencies of these components. The Implicitly Restarted Arnoldi Method (IRAM) is a robust and efficient method for the numerical solution of the generalized eigenproblem Ax = {lambda}Bx, where A and B are sparse matrices, x is an eigenvector, and {lambda} is an eigenvalue. The IRAM is an iterative method for computing extremal eigenvalues; it is an extension of the classic Lanczos method. The mathematical details of the IRAM are too sophisticated to describe here; instead they refer the reader to [1]. A FORTRAN subroutine library that implements various versions of the IRAM is freely available, both in a serial version named ARPACK and parallel version named PARPACK. In this paper they discretize the vector Helmholtz equation using 1st order H(curl) conforming edge elements (also known as Nedelec elements). This discretization results in a generalized eigenvalue problem which can be solved using the IRAM. The question of so-called spurious modes is discussed, and it is shown that applying a spectral transformation completely eliminates these modes, without any need for an additional constraint equation. Typically they use the IRAM to compute a small set (n < 30) of eigenvalues and eigenmodes for a very large systems (N > 100,000).

  13. Solution structure of eggcase silk protein and its implications for silk fiber formation

    PubMed Central

    Lin, Zhi; Huang, Weidong; Zhang, Jingfeng; Fan, Jing-Song; Yang, Daiwen

    2009-01-01

    Spider silks are renowned for their excellent mechanical properties and biomimetic and industrial potentials. They are formed from the natural refolding of water-soluble fibroins with α-helical and random coil structures in silk glands into insoluble fibers with mainly β-structures. The structures of the fibroins at atomic resolution and silk formation mechanism remain largely unknown. Here, we report the 3D structures of individual domains of a ≈366-kDa eggcase silk protein that consists of 20 identical type 1 repetitive domains, one type 2 repetitive domain, and conserved nonrepetitive N- and C-terminal domains. The structures of the individual domains in solution were determined by using NMR techniques. The domain interactions were investigated by NMR and dynamic light-scattering techniques. The formation of micelles and macroscopic fibers from the domains was examined by electron microscopy. We find that either of the terminal domains covalently linked with at least one repetitive domain spontaneously forms micelle-like structures and can be further transformed into fibers at ≥37 °C and a protein concentration of >0.1 wt%. Our biophysical and biochemical experiments indicate that the less hydrophilic terminal domains initiate the assembly of the proteins and form the outer layer of the micelles whereas the more hydrophilic repetitive domains are embedded inside to ensure the formation of the micelle-like structures that are the essential intermediates in silk formation. Our results establish the roles of individual silk protein domains in fiber formation and provide the basis for designing miniature fibroins for producing artificial silks. PMID:19458259

  14. Therapeutic effect of bovine albumin in the experimental fat embolism syndrome.

    PubMed

    Agnantis, N; Gyras, M; Tserkezoglou, A; Apostolikas, N; Papacharalampous, N

    1988-01-01

    The toxic effects of the free fatty acids (FFA) are responsible for the initiation and the clinical manifestations of the fat embolism syndrome (FES). Serum albumin binds to the FFA and by producing atoxic compounds it has a therapeutic effect on the syndrome. In this study we applied bovine albumin to 48 Sprague-Dawley rats which were previously submitted to intravenous infusions of FFA solutions (oleic, palmitic, stearic). The histopathologic lesions observed in their lungs were compared to those of 50 control animals suffering from the FES. The administration of 0.5% bovine albumin solution intravenously and 0.2% intraperitoneally, especially when it was synchronous to the FFA infusion and not metachronous, resulted in substantial and statistically significant therapeutic effects. PMID:3387690

  15. Gold nanoparticles with different amino acid surfaces: serum albumin adsorption, intracellular uptake and cytotoxicity.

    PubMed

    Cai, Huanxin; Yao, Ping

    2014-11-01

    Gold nanoparticles with aspartate, glycine, leucine, lysine, and serine surfaces were produced from the mixed solutions of HAuCl4 and respective amino acids via UV irradiation. The amino acids bind to the nanoparticle surfaces via amine groups and their carboxylic groups extend out to stabilize the nanoparticles. The nanoparticles have diameters of 15-47 nm in pH 7.4 aqueous solution and have diameters of 62-73 nm after 48 h incubation in cell culture containing serum. The nanoparticles adsorb human and bovine serum albumins on their surfaces by specific interactions, characterized by the intrinsic fluorescence quenching of the albumins. The albumin adsorption effectively decreases the aggregation of the nanoparticles in cell culture and also decreases the intracellular uptake of the nanoparticles. The gold nanoparticles produced from leucine and lysine, which have amphiphilic groups on their surfaces, present better biocompatibility than the other gold nanoparticles. PMID:25466455

  16. Experimental evidence on interaction between xenon and bovine serum albumin

    NASA Astrophysics Data System (ADS)

    Wołoszyn, Łukasz; Ilczyszyn, Marek; Ilczyszyn, Maria M.

    Xenon gas interacts with bovine serum albumin (BSA) dissolved in a physiological buffer solution. The fluorescence quenching related to the Trp emission is reversible and depends linearly on the time of saturation by Xe. The most probable site of this interaction is Trp212. The common emission of all BSA fluorophores is also influenced by Xe but this quenching is more complex and suggests: (i) at least two sites occupied by Xe and related to the Tyr and Trp residues; (ii) structural variations of BSA induced by the Xe guest atoms.

  17. Three-dimensional structure of human serum albumin

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.; He, Xiao-Min; Munson, Sibyl H.; Twigg, Pamela D.; Gernert, Kim M.; Broom, M. Beth; Miller, Teresa Y.

    1989-01-01

    The three-dimensional structure of human serum albumin has been solved at 6.0 A resolution by the method of multiple isomorphous replacement. Crystals were grown from solutions of polyethylene glycol in the infrequently observed space group P42(1)2 and diffracted X-rays to lattice d-spacings of less than 2.9 A. The electron density maps are of high quality and revealed the structure as a predominantly alpha-helical globin protein in which the course of the polypeptide can be traced. The binding loci of several organic compounds have been determined.

  18. Interstitial albumin concentration measured during growth of perivascular cuffs in liquid-filled rabbit lung.

    PubMed

    Moe, Sonja M; Conhaim, Robert L; Lai-Fook, Stephen J

    2004-01-01

    The growth rate and albumin concentration of interstitial fluid cuffs were measured in isolated rabbit lungs inflated with albumin solution (3 g/dl) to constant airway (Paw) and vascular pressures for up to 10 h. Cuff size was measured from images of frozen lung sections, and cuff albumin concentration (Cc) was measured from the fluorescence of Evans blue labeled albumin that entered the cuffs from the alveolar space. At 5-cmH2O Paw, cuff size peaked at 1 h and then decreased by 75% in 2 h. The decreased cuff size was consistent with an osmotic absorption into the albumin solution that filled the vascular and alveolar spaces. At 15-cmH2O Paw, cuff size peaked at 0.25 h and then remained constant. Cc rose continuously at both pressures, but was greater at the higher pressure. The increasing Cc with a constant cuff size was modeled as diffusion through epithelial pores. Initial Cc-to-airway albumin concentration ratio was 0.1 at 5-cmH2O Paw and increased to 0.3 at 15 cmH2O, a behavior that indicated an increased permeability with lung inflation. Estimated epithelial reflection coefficient was 0.9 and 0.7, and equivalent epithelial pore radii were 4.5 and 6.1 nm at 5- and 15-cmH2O Paw, respectively. The initial cuff growth occurred against an albumin colloid osmotic pressure gradient because a high interstitial resistance reduced the overall epithelial-interstitial reflection coefficient to the low value of the interstitium. PMID:14660494

  19. Simultaneous injection effective mixing flow analysis of urinary albumin using dye-binding reaction.

    PubMed

    Ratanawimarnwong, Nuanlaor; Ponhong, Kraingkrai; Teshima, Norio; Nacapricha, Duangjai; Grudpan, Kate; Sakai, Tadao; Motomizu, Shoji

    2012-07-15

    A new four-channel simultaneous injection effective mixing flow analysis (SIEMA) system has been assembled for the determination of urinary albumin. The SIEMA system consisted of a syringe pump, two 5-way cross connectors, four holding coils, five 3-way solenoid valves, a 50-cm long mixing coil and a spectrophotometer. Tetrabromophenol blue anion (TBPB) in Triton X-100 micelle reacted with albumin at pH 3.2 to form a blue ion complex with a λ(max) 625nm. TBPB, Triton X-100, acetate buffer and albumin standard solutions were aspirated into four individual holding coils by a syringe pump and then the aspirated zones were simultaneously pushed in the reverse direction to the detector flow cell. Baseline drift, due to adsorption of TBPB-albumin complex on the wall of the hydrophobic PTFE tubing, was minimized by aspiration of Triton X-100 and acetate buffer solutions between samples. The calibration graph was linear in the range of 10-50μg/mL and the detection limit for albumin (3σ) was 0.53μg/mL. The RSD (n=11) at 30μg/mL was 1.35%. The sample throughput was 37/h. With a 10-fold dilution, interference from urine matrix was removed. The proposed method has advantages in terms of simple automation operation and short analysis time. PMID:22817927

  20. Factors influencing the immune response. II. Effects of the physical state of the antigen and of lymphoreticular cell proliferation on the response to intraperitoneal injection of bovine serum albumin in rabbits

    PubMed Central

    Pinckard, R. N.; Weir, D. M.; McBride, W. H.

    1967-01-01

    The injection of Corynebacterium parvum at the same time as centrifuged bovine albumin has been shown not to have the adjuvant effect found when C. parvum is injected 6 days before. The implication of this is discussed and related to mechanisms of antibody synthesis. Whereas particulate alum-precipitated centrifuged bovine albumin was shown to be more effective than centrifuged bovine albumin in inducing primary antibody stimulation, the reverse was true for secondary stimulation by the intraperitoneal route. PMID:6035197

  1. Antagonism of insulin action on muscle by the albumin-bound B chain of insulin

    PubMed Central

    Ensinck, J. W.; Mahler, R. J.; Vallance-Owen, J.

    1965-01-01

    1. The presence of a substance associated with human albumin that exerts anti-insulin activity on the isolated rat diaphragm has been confirmed. This factor has been removed from albumin, thereby providing a source of non-antagonistic carrier protein. 2. Derivatives of the polypeptide B chain of insulin obtained by chemical scission of the interchain disulphide bonds have been separated by conventional techniques. In the presence of non-antagonistic albumin, the reduced and sulpho-B chain preparations inhibited insulin action on muscle. 3. The B chain resulting from reductive cleavage of insulin by bovine-liver extracts, in association with human albumin, exhibited a comparable anti-insulin effect. 4. It is postulated that the B chain interacts with albumin to enable solubilization of the chain and that inhibition of insulin action on muscle may occur as a result of competition for cellular receptor sites by the B chain. 5. The implication of these findings in relation to a circulating insulin antagonist is discussed. PMID:14342222

  2. Adsorption of small biological molecules on silica from diluted aqueous solutions: Quantitative characterization and implications to the Bernal's hypothesis

    NASA Astrophysics Data System (ADS)

    Basiuk, Vladimir A.; Gromovoy, Taras Yu.; Khil'Chevskaya, Elena G.

    1995-08-01

    To describe quantitatively the adsorption of prebiotically important compounds of low molecular weight (amino acids, short linear peptides, cyclic dipeptides, the Krebs's cycle and other carboxylic acids, nucleosides and related phosphates) on silica surface from diluted neutral aqueous solutions, equilibrium constants (K) and free energies (-ΔG) of adsorption were determined from the retention values measured by means of high-performance liquid chromatography on a silica gel column and from the isotherms measured under static conditions. For most carboxylic acids (including amino acids and linear peptides) -ΔG values were negative and K<1, thus showing very weak adsorption. Cyclic dipeptides (2,5-piperazinediones) exhibited higher adsorbability; -ΔG>0 and K>1 were found for most of them. Influence of the structure of α-substituent on the adsorbability is analyzed. A linear dependence of -ΔG on the number of aliphatic carbon atoms in a sorbate molecule was found for the series of aliphatic bifunctional amino acids, related dipeptides and 2,5-piperazinediones, as well as for the row from glycine to triglycyl glycine. The adsorption of nucleosides and their phosphates is characterized by much higherK and -ΔG values (of the order of 102 and 104, respectively). The adsorption data available from our work and literature are summarized and discussed with implications to the Bernal's hypothesis on the roles of solid surfaces in the prebiotic formation of biopolymers from monomeric ‘building blocks’.

  3. Repression of the albumin gene in Novikoff hepatoma cells.

    PubMed Central

    Capetanaki, Y G; Flytzanis, C N; Alonso, A

    1982-01-01

    Novikoff hepatoma cells have lost their capacity to synthesize albumin. As a first approach to study the mechanisms underlying this event, in vitro translation in a reticulocyte system was performed using total polyadenylated mRNA from rat liver and Novikoff hepatoma cells. Immunoprecipitation of the in vitro translation products with albumin-specific antibody revealed a total lack of albumin synthesis in Novikoff hepatoma, suggesting the absence of functional albumin mRNA in these cells. Titration experiments using as probe albumin cDNA cloned in pBR322 plasmid demonstrated the absence of albumin-specific sequences in both polysomal and nuclear polyadenylated and total RNA from Novikoff cells. This albumin recombinant plasmid was obtained by screening a rat liver cDNA library with albumin [32P]cDNA reverse transcribed from immuno-precipitated mRNA. The presence of an albumin-specific gene insert was documented with translation assays as well as by restriction mapping. Repression of the albumin gene at the transcriptional level was further demonstrated by RNA blotting experiments using the cloned albumin cDNA probe. Genomic DNA blots using the cloned albumin cDNA as probe did not reveal any large-scale deletions, insertions, or rearrangements in the albumin gene, suggesting that the processes involved in the suppression of albumin mRNA synthesis do not involve extensive genomic rearrangements. Images PMID:6180302

  4. A novel biosensor for bovine serum albumin based on fluorescent self-assembled sandwich bilayers.

    PubMed

    Sun, Xiangying; Liu, Bin; He, Fei

    2009-01-01

    Fluorescent dyes butyl rhodamine B were assembled via a DL-cystenine intermediate onto quartz wafers whose surface had first adsorbed gold nanoparticles. Hence self-assembled sandwich bilayers with nanocomposite structure were constructed which can be used as a biosensor for bovine serum albumin. The biosensor-based self-assembled monolayers (SAMs) are regenerable and have high sensitivity, five orders of magnitude higher than that of bulk solution phase sensing. The effects of existing forms of dyes on the fluorescence spectra of bilayers in the presence of bovine serum albumin were investigated. PMID:18785615

  5. Induced Long-Range Attractive Potentials of Human Serum Albumin by Ligand Binding

    SciTech Connect

    Sato, Takaaki; Komatsu, Teruyuki; Nakagawa, Akito; Tsuchida, Eishun

    2007-05-18

    Small-angle x-ray scattering and dielectric spectroscopy investigation on the solutions of recombinant human serum albumin and its heme hybrid revealed that heme incorporation induces a specific long-range attractive potential between protein molecules. This is evidenced by the enhanced forward intensity upon heme binding, despite no hindrance to rotatory Brownian motion, unbiased colloid osmotic pressure, and discontiguous nearest-neighbor distance, confirming monodispersity of the proteins. The heme-induced potential may play a trigger role in recognition of the ligand-filled human serum albumins in the circulatory system.

  6. Preliminary crystallographic studies of four crystal forms of serum albumin

    NASA Technical Reports Server (NTRS)

    Carter, D. C.; Chang, B.; Ho, J. X.; Keeling, K.; Krishnasami, Z.

    1994-01-01

    Several crystal forms of serum albumin suitable for three-dimensional structure determination have been grown. These forms include crystals of recombinant and wild-type human serum albumin, baboon serum albumin, and canine serum albumin. The intrinsic limits of X-ray diffraction for these crystals are in the range 0.28-0.22 nm. Two of the crystal forms produced from human and canine albumin include incorporated long-chain fatty acids. Molecular replacement experiments have been successfully conducted on each crystal form using the previously determined atomic coordinates of human serum albumin illustrating the conserved tertiary structure.

  7. Preliminary crystallographic studies of four crystal forms of serum albumin.

    PubMed

    Carter, D C; Chang, B; Ho, J X; Keeling, K; Krishnasami, Z

    1994-12-15

    Several crystal forms of serum albumin suitable for three-dimensional structure determination have been grown. These forms include crystals of recombinant and wild-type human serum albumin, baboon serum albumin, and canine serum albumin. The intrinsic limits of X-ray diffraction for these crystals are in the range 0.28-0.22 nm. Two of the crystal forms produced from human and canine albumin include incorporated long-chain fatty acids. Molecular replacement experiments have been successfully conducted on each crystal form using the previously determined atomic coordinates of human serum albumin illustrating the conserved tertiary structure. PMID:7813459

  8. Polymerized soluble venom--human serum albumin

    SciTech Connect

    Patterson, R.; Suszko, I.M.; Grammer, L.C.

    1985-03-01

    Extensive previous studies have demonstrated that attempts to produce polymers of Hymenoptera venoms for human immunotherapy resulted in insoluble precipitates that could be injected with safety but with very limited immunogenicity in allergic patients. We now report soluble polymers prepared by conjugating bee venom with human serum albumin with glutaraldehyde. The bee venom-albumin polymer (BVAP) preparation was fractionated on Sephacryl S-300 to have a molecular weight range higher than catalase. /sup 125/I-labeled bee venom phospholipase A was almost completely incorporated into BVAP. Rabbit antibody responses to bee venom and bee venom phospholipase A were induced by BVAP. Human antisera against bee venom were absorbed by BVAP. No new antigenic determinants on BVAP were present as evidenced by absorption of antisera against BVAP by bee venom and albumin. BVAP has potential immunotherapeutic value in patients with anaphylactic sensitivity to bee venom.

  9. Bovine Serum Albumin binding to CoCrMo nanoparticles and the influence on dissolution

    NASA Astrophysics Data System (ADS)

    Simoes, T. A.; Brown, A. P.; Milne, S. J.; Brydson, R. M. D.

    2015-10-01

    CoCrMo alloys exhibit good mechanical properties, excellent biocompatibility and are widely utilised in orthopaedic joint replacements. Metal-on-metal hip implant degradation leads to the release of metal ions and nanoparticles, which persist through the implant's life and could be a possible cause of health complications. This study correlates preferential binding between proteins and metal alloy nanoparticles to the alloy's corrosion behaviour and the release of metal ions. TEM images show the formation of a protein corona in all particles immersed in albumin containing solutions. Only molybdenum release was significant in these tests, suggesting high dissolution of this element when CoCrMo alloy nanoparticles are produced as wear debris in the presence of serum albumin. The same trend was observed during extended exposure of molybdenum reference nanoparticles to albumin.

  10. Adsorbed serum albumin is permissive to macrophage attachment to perfluorocarbon polymer surfaces in culture.

    PubMed

    Godek, M L; Michel, R; Chamberlain, L M; Castner, D G; Grainger, D W

    2009-02-01

    Monocyte/macrophage adhesion to biomaterials, correlated with foreign body response, occurs through protein-mediated surface interactions. Albumin-selective perfluorocarbon (FC) biomaterials are generally poorly cell-conducive because of insufficient receptor-mediated surface interactions, but macrophages bind to albumin-coated substrates and also preferentially to highly hydrophobic fluorinated surfaces. Bone marrow macrophages (BMMO) and IC-21, RAW 264.7, and J774A.1 monocyte/macrophage cells were cultured on FC surfaces. Protein deposition onto two distinct FC surfaces from complex and single-component solutions was tracked using fluorescence and time-of-flight secondary ion mass spectrometry (ToF-SIMS) methods. Cell adhesion and growth on protein pretreated substrates were compared by light microscopy. Flow cytometry and integrin-directed antibody receptor blocking were used to assess integrins critical for monocyte/macrophage adhesion in vitro. Albumin predominantly adsorbs onto both FC surfaces from 10% serum. In cultures preadsorbed with albumin or serum-dilutions, BMMO responded similar to IC-21 at early time points. Compared with Teflon AF, plasma-polymerized FC was less permissive to extended cell proliferation. The beta(2) integrins play major roles in macrophage adhesion to FC surfaces: antibody blocking significantly disrupted cell adhesion. Albumin-mediated cell adhesion mechanisms to FC surfaces could not be clarified. Primary BMMO and secondary IC-21 macrophages behave similarly on FC surfaces, regardless of preadsorbed protein biasing, with respect to adhesion, cell morphology, motility, and proliferation. PMID:18306309

  11. Adsorbed serum albumin is permissive to macrophage attachment to perfluorocarbon polymer surfaces in culture

    PubMed Central

    Godek, M.L.; Michel, R.; Chamberlain, L. M.; Castner, D. G.; Grainger, D.W.

    2013-01-01

    Monocyte/macrophage adhesion to biomaterials, correlated with foreign body response, occurs through protein-mediated surface interactions. Albumin-selective perfluorocarbon (FC) biomaterials are generally poorly cell-conducive due to insufficient receptor-mediated surface interactions, but macrophages bind to albumin-coated substrates and also preferentially to highly hydrophobic fluorinated surfaces. Bone marrow macrophages (BMMO) and IC-21, RAW 264.7 and J774A.1 monocyte/macrophage cells were cultured on FC surfaces. Protein deposition onto two distinct FC surfaces from complex and single-component solutions was tracked using fluorescence and time-of-flight secondary ion mass spectrometry (ToF-SIMS) methods. Cell adhesion and growth on protein pre-treated substrates were compared by light microscopy. Flow cytometry and integrin-directed antibody receptor blocking assessed integrins critical for monocyte/macrophage adhesion in vitro. Albumin predominantly adsorbs onto both FC surfaces from 10% serum. In cultures pre-adsorbed with albumin or serum-dilutions, BMMO responded similar to IC-21 at early time points. Compared to Teflon® AF, plasma-polymerized FC was less permissive to extended cell proliferation. The β2 integrins play major roles in macrophage adhesion to FC surfaces: antibody blocking significantly disrupted cell adhesion. Albumin-mediated cell adhesion mechanisms to FC surfaces could not be clarified. Primary BMMO and secondary IC-21 macrophages behave similarly on FC surfaces, regardless of pre-adsorbed protein biasing, with respect to adhesion, cell morphology, motility and proliferation. PMID:18306309

  12. Electrostatic unfolding and interactions of albumin driven by pH changes: a molecular dynamics study.

    PubMed

    Baler, K; Martin, O A; Carignano, M A; Ameer, G A; Vila, J A; Szleifer, I

    2014-01-30

    A better understanding of protein aggregation is bound to translate into critical advances in several areas, including the treatment of misfolded protein disorders and the development of self-assembling biomaterials for novel commercial applications. Because of its ubiquity and clinical potential, albumin is one of the best-characterized models in protein aggregation research; but its properties in different conditions are not completely understood. Here, we carried out all-atom molecular dynamics simulations of albumin to understand how electrostatics can affect the conformation of a single albumin molecule just prior to self-assembly. We then analyzed the tertiary structure and solvent accessible surface area of albumin after electrostatically triggered partial denaturation. The data obtained from these single protein simulations allowed us to investigate the effect of electrostatic interactions between two proteins. The results of these simulations suggested that hydrophobic attractions and counterion binding may be strong enough to effectively overcome the electrostatic repulsions between the highly charged monomers. This work contributes to our general understanding of protein aggregation mechanisms, the importance of explicit consideration of free ions in protein solutions, provides critical new insights about the equilibrium conformation of albumin in its partially denatured state at low pH, and may spur significant progress in our efforts to develop biocompatible protein hydrogels driven by electrostatic partial denaturation. PMID:24393011

  13. Electrostatic Unfolding and Interactions of Albumin Driven by pH Changes: A Molecular Dynamics Study

    PubMed Central

    2015-01-01

    A better understanding of protein aggregation is bound to translate into critical advances in several areas, including the treatment of misfolded protein disorders and the development of self-assembling biomaterials for novel commercial applications. Because of its ubiquity and clinical potential, albumin is one of the best-characterized models in protein aggregation research; but its properties in different conditions are not completely understood. Here, we carried out all-atom molecular dynamics simulations of albumin to understand how electrostatics can affect the conformation of a single albumin molecule just prior to self-assembly. We then analyzed the tertiary structure and solvent accessible surface area of albumin after electrostatically triggered partial denaturation. The data obtained from these single protein simulations allowed us to investigate the effect of electrostatic interactions between two proteins. The results of these simulations suggested that hydrophobic attractions and counterion binding may be strong enough to effectively overcome the electrostatic repulsions between the highly charged monomers. This work contributes to our general understanding of protein aggregation mechanisms, the importance of explicit consideration of free ions in protein solutions, provides critical new insights about the equilibrium conformation of albumin in its partially denatured state at low pH, and may spur significant progress in our efforts to develop biocompatible protein hydrogels driven by electrostatic partial denaturation. PMID:24393011

  14. Effect of different albumin concentrations in extracorporeal circuit prime on perioperative fluid status in young children.

    PubMed

    Yu, Kun; Liu, Yinglong; Hei, Feilong; Li, Jingwen; Long, Cun

    2008-01-01

    This study examined the effects of different dosages of albumin priming for extracorporeal circuit (ECC) on perioperative fluid status and fluid management in young children. A total of 151 consecutive pediatric patients (2-36 months old) scheduled for open heart surgery, were divided into two groups randomly, to receive either a 3% albumin solution (L group, n = 68) or a 5% albumin (H group, n = 83). Perioperative fluid intake, urine output, blood loss, diuretic dosage, the use of allogeneic blood products, ultrafiltration, and daily balance were recorded for 24 hrs in intensive care unit (ICU). Serial hematocrits, colloid osmotic pressure (COP) were measured. Outcomes and complications were documented. There were no significant differences in demographics, types of surgical procedures, baseline data such as hemoglobin, COP, and serum albumin. Patients in H group had significantly higher COPs, less urine output and more diuretic usage during operation and postoperatively (p < 0.05); at 6 hrs postoperatively, there were no differences between two groups. No statistically significant differences were found between the two groups in blood loss and the amount of allogenic blood products infused, length of mechanical ventilation, ICU or hospital stay, complications, or mortality. Higher concentration of albumin prime in ECC showed decreased positive fluid balances, but produced less urine output and required more diuretic usage postoperatively. Thus, no significant clinical benefit resulted from the increased dosage. PMID:18812733

  15. Interaction of some cardiovascular drugs with bovine serum albumin at physiological conditions using glassy carbon electrode: A new approach.

    PubMed

    Afsharan, Hadi; Hasanzadeh, Mohammad; Shadjou, Nasrin; Jouyban, Abolghasem

    2016-08-01

    In this report, for the first time, the non-modified glassy carbon electrode was used for detection of cardiovascular drug interaction with bovine serum albumin (BSA). These interactions were tested at physiological conditions (T=37°C and pH=7.4 phosphate buffer solution) in different incubation times (0-4h) by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). The applications of DPV for quantitative investigation of some cardiovascular drug interaction with BSA (as a model of serum albumin proteins) were discussed. The herein described approach is expected to promote the exploitation of electrochemically-based methods for the study of drug-serum albumin protein interaction which is necessary in biochemical and biosensing studies. This report may open a new window to application of electrochemical sensors towards interactions of cardiovascular drugs with BSA and human serum albumin (HAS) in the near future. PMID:27157732

  16. Comparison of antioxidant properties of different therapeutic albumin preparations.

    PubMed

    Plantier, Jean-Luc; Duretz, Véronique; Devos, Véronique; Urbain, Rémi; Jorieux, Sylvie

    2016-07-01

    Albumin displays several important functions for homeostasis amongst which the maintenance of the plasma redox-state. The study aim was to compare the redox state of pharmaceutical human albumin preparations since it reflects the oxidation-reduction status of the surrounding environment. Using an array of analytical methods, four commercially available albumins were compared with respect to their structural characteristics (cobalt ion binding, glycation, spectrophotometric and fluorometric profiles) and their ability to scavenge hydroxyl, peroxyl or free radicals. The different albumins exhibited a similar structural profile as well as hydroxyl and peroxyl scavenging activities. By contrast, the albumin from LFB (Vialebex(®)) possessed a significantly higher capacity to transfer electrons to DPPH, as compared with other albumins that was correlated with the level of free cysteine-34. Commercially available albumins differed for some of their antioxidant properties. The albumin preparation possessing the highest level of free cysteine-34 exhibited the highest antioxidant potential. PMID:27156143

  17. Trajectories of Serum Albumin Predict Survival of Peritoneal Dialysis Patients

    PubMed Central

    Chiu, Ping-Fang; Tsai, Chun-Chieh; Wu, Chia-Lin; Yang, Tse-Yen; Liou, Hung-Hsiang; Chen, Hung-Lin; Kor, Chew-Teng; Chang, Chia-Chu; Chang, Horng-Rong

    2016-01-01

    Abstract Although initial serum albumin level is highly associated with overall and cardiovascular mortality in peritoneal dialysis (PD) patients, we consider that the dynamic change and trend of albumin after initiation of PD are also essential. We enrolled patients who received PD for more than 3 months from January 1999 to March 2014. We categorized these patients into 2 groups by the difference in serum albumin level (Δalbumin = difference between peak with initial albumin level = peak albumin level − initial albumin level) after PD. The patients with Δalbumin < 0.2 g/dL (median level) were considered as group A (n, number = 238) and those with Δalbumin ≥ 0.2 g/dL were considered as group B (n = 278). Further, we stratified these patients into quartiles: Q1 Δalbumin < −0.2 g/dL; Q2, −0.2 ≦∼ <0.2 g/dL; Q3, 0.2 ≦∼ <0.6 g/dL; and Q4, ≥0.6 g/dL. Regression analysis was performed to determine the correlation of initial albumin and Δalbumin. Group A patients presented with higher levels of serum albumin (3.71 ± 0.54 vs 3.04 ± 0.55 g/dL; P < 0.001) and hematocrit as well as better initial residual renal function. However, those in group A had lower serum albumin increment and downward-sloped trends after dialysis. In contrast, the albumin trend was upward sloped and the increment of albumin was remarkable in group B, despite the high prevalence of cardiovascular diseases and diabetes. Overtime, group A patients had poorer survival and experienced more frequent and longer hospitalizations. Group Q1 patients with least albumin increment had worst survival. Group Q4 patients with lowest initial albumin also had poor survival. Age, diabetes, cardiovascular diseases, BMI, initial albumin, and Δalbumin could affect patient outcomes independently. Regression analysis showed a better outcome can be obtained if the initial albumin level is at least above 3.15 g/dL. (Initial albumin level

  18. Micropinocytic Ingestion of Glycosylated Albumin by Isolated Microvessels: Possible Role in Pathogenesis of Diabetic Microangiopathy

    NASA Astrophysics Data System (ADS)

    Williams, Stuart K.; Devenny, James J.; Bitensky, Mark W.

    1981-04-01

    Microvessels isolated from rat epididymal fat exhibit differential vesicular ingestion rates for unmodified and nonenzymatically glycosylated rat albumin. While unmodified rat albumin is excluded from ingestion by endothelial micropinocytic vesicles, glycosylated albumin is avidly taken up by endocytosis. Interaction of albumin and glycosylated albumin with endothelium was studied with a double-label fluorescence assay of micropinocytosis. When glycosylated albumin was present at a concentration of 6% with respect to total albumin (the level found in ``non diabetic'' serum), only glycosylated albumin was ingested. At higher concentrations of glycosylated albumin (those found in diabetic serum), both albumin and glycosylated albumin are ingested. Glycosylation of endothelial membrane components results in stimulated ingestion of glycosylated albumin, persistent exclusion of unmodified albumin, and unaltered micropinocytic ingestion of native ferritin. These results indicate that nonenzymatic glycosylation of serum albumin may result in rapid vesicle-mediated extravasation of albumin. Chronic microvascular leakage of glycosylated albumin could contribute to the pathogenesis of diabetic microangiopathy.

  19. Interaction of Citrinin with Human Serum Albumin

    PubMed Central

    Poór, Miklós; Lemli, Beáta; Bálint, Mónika; Hetényi, Csaba; Sali, Nikolett; Kőszegi, Tamás; Kunsági-Máté, Sándor

    2015-01-01

    Citrinin (CIT) is a mycotoxin produced by several Aspergillus, Penicillium, and Monascus species. CIT occurs worldwide in different foods and drinks and causes health problems for humans and animals. Human serum albumin (HSA) is the most abundant plasma protein in human circulation. Albumin forms stable complexes with many drugs and xenobiotics; therefore, HSA commonly plays important role in the pharmacokinetics or toxicokinetics of numerous compounds. However, the interaction of CIT with HSA is poorly characterized yet. In this study, the complex formation of CIT with HSA was investigated using fluorescence spectroscopy and ultrafiltration techniques. For the deeper understanding of the interaction, thermodynamic, and molecular modeling studies were performed as well. Our results suggest that CIT forms stable complex with HSA (logK ~ 5.3) and its primary binding site is located in subdomain IIA (Sudlow’s Site I). In vitro cell experiments also recommend that CIT-HSA interaction may have biological relevance. Finally, the complex formations of CIT with bovine, porcine, and rat serum albumin were investigated, in order to test the potential species differences of CIT-albumin interactions. PMID:26633504

  20. Lymphatic albumin clearance from psoriatic skin

    SciTech Connect

    Staberg, B.; Klemp, P.; Aasted, M.; Worm, A.M.; Lund, P.

    1983-12-01

    In nine patients with untreated psoriasis vulgaris, human serum albumin labelled with /sup 125/I or /sup 131/I was injected intradermally in symmetrically located involved and uninvolved skin. The activity of the depots was followed by external detection, and the arrival of labelled albumin in plasma was monitored. In involved psoriatic skin the local mean half-time (T1/2) for tracer disappearance was 20.8 +/- 8.2 (S.D.) hr and in clinically normal skin, 29.1 +/- 9.6 (S.D.) hr. The difference was significant (p less than 0.002). Accordingly, the tracer from involved skin reached higher plasma levels than the tracer from uninvolved skin. However, under slight lymphatic stasis the appearance rate of radiolabelled albumin in plasma from both tissues was minimal during 1 to 2 hours after the injection, indicating that a local direct transvascular drainage of plasma albumin from the interstitium of diseased and normal skin was negligible. We conclude that the previously demonstrated increased extravasation of plasma proteins in involved psoriatic skin is compensated by an increased lymphatic drainage of plasma proteins, and not by an increased local transvascular return.

  1. Design of Albumin-Coated Microbubbles Loaded With Polylactide Nanoparticles

    PubMed Central

    Gauthier, Marianne; Yin, Qian; Cheng, Jianjun; O'Brien, William D.

    2015-01-01

    Objectives A protocol was designed to produce albumin-coated microbubbles (MBs) loaded with functionalized polylactide (PLA) nanoparticles (NPs) for future drug delivery studies. Methods Microbubbles resulted from the sonication of 5% bovine serum albumin and 15% dextrose solution. Functionalized NPs were produced by mixing fluorescent PLA and PLA-polyethylene glycol-carboxylate conjugates. Nanoparticle-loaded MBs resulted from the covalent conjugation of functionalized NPs and MBs. Three NP/MB volume ratios (1/1, 1/10, and 1/100) and unloaded MBs were produced and compared. Statistical evaluations were based on quantitative analysis of 3 parameters at 4 time points (1, 4, 5, and 6 days post MB fabrication): MB diameter using a circle detection routine based on the Hough transform, MB number density using a hemocytometer, and NP-loading yield based on MB counts from fluorescence and light microscopic images. Loading capacity of the albumin-coated MBs was evaluated by fluorescence. Results Loaded MB sizes were stable over 6 days after production and were not significantly different from that of time-matched unloaded MBs. Number density evaluation showed that only 1/1 NP/MB volume ratio and unloaded MB number densities were stable over time, and that the 1/1 MB number density evaluated at each time point was not significantly different from that of unloaded MBs. The 1/10 and 1/100 NP/MB volume ratios had unstable number densities that were significantly different from that of unloaded MBs (P < .05). Fluorescence evaluation suggested that 1/1 MBs had a higher NP-loading yield than 1/10 and 1/100 MBs. Quantitative loading evaluation suggested that the 1/1 MBs had a loading capacity of 3700 NPs/MB. Conclusions A protocol was developed to load albumin MBs with functionalized PLA NPs for further drug delivery studies. The 1/1 NP/MB volume ratio appeared to be the most efficient to produce stable loaded MBs with a loading capacity of 3700 NPs/MB. PMID:26206822

  2. Drug Delivery Vehicles Based on Albumin-Polymer Conjugates.

    PubMed

    Jiang, Yanyan; Stenzel, Martina

    2016-06-01

    Albumin has been a popular building block to create nanoparticles for drug delivery purposes. The performance of albumin as a drug carrier can be enhanced by combining protein with polymers, which allows the design of carriers to encompass a broader spectrum of drugs while features unique to synthetic polymers such as stimuli-responsiveness are introduced. Nanoparticles based on polymer-albumin hybrids can be divided into two classes: one that carries album as a bioactive surface coating and the other that uses albumin as biocompatible, although nonbioactive, building block. Nanoparticles with bioactive albumin surface coating can either be prepared by self-assembly of albumin-polymer conjugates or by postcoating of existing nanoparticles with albumin. Albumin has also been used as building block, either in its native or denatured form. Existing albumin nanoparticles are coated with polymers, which can influence the degradation of albumin or impact on the drug release. Finally, an alternative way of using albumin by denaturing the protein to generate a highly functional chain, which can be modified with polymer, has been presented. These albumin nanoparticles are designed to be extremely versatile so that they can deliver a wide variety of drugs, including traditional hydrophobic drugs, metal-based drugs and even therapeutic proteins and siRNA. PMID:26947019

  3. 21 CFR 866.5040 - Albumin immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Albumin immunological test system. 866.5040... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5040 Albumin immunological test system. (a) Identification. An albumin immunological test system is a device that consists...

  4. Zinc inhibits glycation induced structural, functional modifications in albumin and protects erythrocytes from glycated albumin toxicity.

    PubMed

    Tupe, Rashmi; Kulkarni, Amruta; Adeshara, Krishna; Sankhe, Neena; Shaikh, Shamim; Dalal, Sayli; Bhosale, Siddharth; Gaikwad, Sushama

    2015-08-01

    The present work aims to investigate the concentration and time dependant effect of zinc on the in vitro non enzymatic modifications of albumin by diabetic levels of glucose. Further, preventive and curative effect of zinc was studied by adding zinc before and after initiation of glycation respectively. Glycation of albumin was done at different concentrations of zinc (125, 250 and 500 μM) at different time intervals (21, 28 and 35 days) with appropriate controls. The antiglycation potential of zinc was assessed by estimating different markers of albumin glycation (fructosamines, carbonyls, bound sugar, AGEs), structural modifications (free amino, thiol group, β amyloid, native PAGE, ANS binding, fluorescence lifetime decay and CD analysis) and functional properties (antioxidant activity, hemolysis). Zinc at highest concentration (500 μM) significantly reduced modifications of albumin which was comparable to aminoguanidine and also protected secondary and tertiary structure of albumin after 28 days of incubation. Zinc exhibited significant protective effect on erythrocytes by inhibiting hemolysis. Thus the present study indicate preventive mode of albumin glycation inhibition by zinc. PMID:26027608

  5. Hydraulic conductivity, albumin reflection and diffusion coefficients of pig mediastinal pleura.

    PubMed

    Parameswaran, S; Brown, L V; Ibbott, G S; Lai-Fook, S J

    1999-09-01

    Hydraulic conductivity (L), albumin reflection coefficient (sigma), and albumin diffusion coefficient (D) were measured across pig mediastinal pleura. The tissue (7 mm diameter) was bonded between two chambers. Flow (Q) of lactated Ringer solution between the chambers was measured in turn at driving pressures (DeltaP) of 2, 4, and 6 cm H(2)O. Value of L was proportional to the slope of the Q-DeltaP curve. Then Q was measured in turn at three albumin osmotic pressure differences (Deltapi equivalent to -1, -2, and -3 g/dl albumin concentration difference, DeltaC) with DeltaP constant at either 2, 3, 4, or 6 cm H(2)O. From Starling's equation, magnitude of sigma was the slope of the Q-Deltapi curve divided by the slope of the Q-DeltaP curve. We measured the diffusion of 0, 2, 5, and 10 g/dl albumin with tracer (125)I-albumin. Tracer mass (M) that diffused across the pleura was measured for 10 h using a well-type NaI(T1) detector. D was calculated from the slope of the M-time curve. Values of L averaged 2.0 x 10(-8) cm(3). s(-1). dyne(-1) (n = 23). Values of sigma were small (0.02-0.05) and sigma increased as flow increased 20-fold. D (n = 24) increased 3-fold from 2.7 x 10(-8) cm(2)/s as DeltaC increased from 0 to 10 g/dl. The small values of sigma indicated that mediastinal pleura provided little restriction to the passage of protein. PMID:10458927

  6. ATTIRE: Albumin To prevenT Infection in chronic liveR failurE: study protocol for a single-arm feasibility trial

    PubMed Central

    Muirhead, Nicola; Shabir, Zainib; PH De Maeyer, Roel; Maini, Alexander AN; W Gilroy, Derek; J O'Brien, Alastair

    2016-01-01

    Introduction Circulating prostaglandin E2 levels are elevated in acutely decompensated cirrhosis and have been shown to contribute to immune suppression. Albumin binds and inactivates this hormone. Human albumin solution could thus be repurposed as an immune restorative drug in these patients. This feasibility study aims to determine whether it is possible and safe to restore serum albumin to >30 g/L and maintain it at this level in patients admitted with acute decompensated cirrhosis using repeated 20% human albumin infusions according to daily serum albumin levels. Methods and analysis Albumin To prevenT Infection in chronic liveR failurE (ATTIRE) stage 1 is a multicentre, open label dose feasibility trial. Patients with acutely decompensated cirrhosis admitted to hospital with a serum albumin of <30 g/L are eligible, subject to exclusion criteria. Daily intravenous human albumin solution will be infused, according to serum albumin levels, for up to 14 days or discharge in all patients. The primary end point is daily serum albumin levels for the duration of the treatment period and the secondary end point is plasma-induced macrophage dysfunction. The trial will recruit 80 patients. Outcomes will be used to assist with study design for an 866 patient randomised controlled trial at more than 30 sites across the UK. Ethics and dissemination Research ethics approval was given by the London-Brent research ethics committee (ref: 15/LO/0104). The clinical trials authorisation was issued by the medicines and healthcare products regulatory agency (ref: 20363/0350/001-0001). Results Will be disseminated through peer reviewed journals and international conferences. Recruitment of the first participant occurred on 26/05/2015. Trial registration number The trial is registered with the European Medicines Agency (EudraCT 2014-002300-24) and has been adopted by the NIHR (ISRCTN 14174793). This manuscript refers to V.4.0 of the protocol; Pre-results. PMID:26810999

  7. Hydrophobic conjugated microporous polymers for sorption of human serum albumin

    NASA Astrophysics Data System (ADS)

    Zheng, Chunli; Du, Miaomiao; Feng, Shanshan; Sun, Hanxue; Li, An; He, Chi; Zhang, TianCheng; Wang, Qiaorui; Wei, Wei

    2016-02-01

    This paper investigated the sorption of human serum albumin (HSA) from water by three kinds of conjugated microporous polymers (CMPs) with surface hydrophobicity and intrinsic porosity. It was found that the three CMPs captured HSA with fast sorption kinetics and good working capacity. Equilibrium was obtained at 80 min for all the tests, and the maximum sorption quantity (qm) ranged from 0.07 to 0.14 mg/mg. With the increase in the particle external surface area of the CMPs, a greater extent of HSA sorption was achieved. Moreover, promoting the dispersion of CMPs in HSA aqueous solution was also beneficial to the extraction. Attenuated Total Reflection Fourier Transform Infrared spectroscopy verified the interactions between the CMPs and the Nsbnd H, Cdbnd O, and Csbnd N groups of HSA. This paper might provide fundamental guidance for the practical application of CMPs to proteins separation and recovery.

  8. A Dual Electrochemical Sensor Based on a Test-strip Assay for the Quantitative Determination of Albumin and Creatinine.

    PubMed

    Yasukawa, Tomoyuki; Kiba, Yuya; Mizutani, Fumio

    2015-01-01

    A dual-electrochemical sensor based on a test-strip assay with immunochemistry and enzyme reactions has been developed for the determination of albumin and creatinine. Each nitrocellulose membrane with an immobilization area of an anti-albumin antibody or three enzymes was prepared in the device with three working electrodes for measuring albumin, creatinine, and ascorbic acid, as well as an Ag/AgCl electrode used as a counter/pseudo-reference electrode. The reactions of three enzymes were initiated by flowing a solution containing creatinine to detect an oxidation current of hydrogen peroxide. A sandwich-type immunocomplex was formed by albumin and antibody labeled with glucose oxidase (GOx). Captured GOx catalyzed the reduction of Fe(CN)6(3-) to Fe(CN)6(4-), which was oxidized electrochemically to determine the captured albumin. The responses for creatinine and albumin increased with the concentrations in millimolar order and over the range 18.75 - 150 μg mL(-1), respectively. The present sensor would be a distinct demonstration for producing quantitative dual-assays for various biomolecules used for clinical diagnoses. PMID:26165278

  9. (PCG) Protein Crystal Growth Human Serum Albumin

    NASA Technical Reports Server (NTRS)

    1989-01-01

    (PCG) Protein Crystal Growth Human Serum Albumin. Contributes to many transport and regulatory processes and has multifunctional binding properties which range from various metals, to fatty acids, hormones, and a wide spectrum of therapeutic drugs. The most abundant protein of the circulatory system. It binds and transports an incredible variety of biological and pharmaceutical ligands throughout the blood stream. Principal Investigator on STS-26 was Larry DeLucas.

  10. (PCG) Protein Crystal Growth Horse Serum Albumin

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Horse Serum Albumin crystals grown during the USML-1 (STS-50) mission's Protein Crystal Growth Glovebox Experiment. These crystals were grown using a vapor diffusion technique at 22 degrees C. The crystals were allowed to grow for nine days while in orbit. Crystals of 1.0 mm in length were produced. The most abundant blood serum protein, regulates blood pressure and transports ions, metabolites, and therapeutic drugs. Principal Investigator was Edward Meehan.

  11. The role of albumin in nutritional support.

    PubMed

    Mobarhan, S

    1988-12-01

    Hypoalbuminemia is considered one of the hallmarks of protein-calorie malnutrition and chronic liver disease. Recently, serum albumin has also been proposed as a critical predictor of the response to nutritional support and tolerance to enteral feeding in critically ill patients. Albumin is essential for maintenance of plasma colloidal osmotic pressure, prevention of edema, and transport of certain drugs and nutrients. Experimental studies have shown that rapid plasma expansion and reduced plasma protein concentration and osmotic pressure induce a net secretion of sodium and water into the small intestinal lumen. However, the effects of chronic hypoalbuminemia per se on intestinal absorption, independent of malnutrition, have not been fully studied. It is documented that both chronic illness and malnutrition may profoundly affect intestinal anatomical structure and function, inducing some degree of malabsorption. In the last few years, some have advocated albumin infusion to improve clinical response to patients with hypoalbuminemia receiving parenteral nutritional support or to reduce intestinal intolerance and diarrhea in patients receiving enteral tube feeding. A review of the literature shows that both clinical and experimental data to support these suggestions are scarce and further investigations are needed. Hypoalbuminemia is one of many parameters of malnutrition, and it is unlikely that correction of a single parameter for a short time would lead to major clinical benefits. PMID:3147998

  12. Serum albumin complexation of acetylsalicylic acid metabolites.

    PubMed

    Jurkowski, Wiktor; Porebski, Grzegorz; Obtułowicz, Krystyna; Roterman, Irena

    2009-06-01

    One possible origin of the type I hypersensitivity reaction is reaction of drugs such as acetylsalicylic acid and its metabolites being complexed with human serum albumin. Albumin, being transporting molecule abundant in blood plasma is able to bind large array of ligands varying from small single carbon particles to long hydrophobic tailed lipidic acids (e.g. myristic acid). This non specificity is possible because of multi domain scaffold and large flexibility of inter-domain loops, which results in serious reorientation of domains. Hypothesis that acetylsalicylic acid metabolites may play indirect role in activation of allergic reaction has been tested. Binding of acetylsalicylic acid metabolites in intra-domain space causes significant increase of liability of domains IIIA and IIIB. One of metabolites, salicyluric acid, once is bound causes distortion and partial unfolding of helices in domains IA, IIB and IIIB. Changed are both directions and amplitude of relative motions as well as intra-domain distances. In result albumin is able to cross-link of adjacent IgE receptors which subsequently starts allergic reaction. PMID:19689242

  13. Megalin/Cubulin-Lysosome-mediated Albumin Reabsorption Is Involved in the Tubular Cell Activation of NLRP3 Inflammasome and Tubulointerstitial Inflammation*

    PubMed Central

    Liu, Dan; Wen, Yi; Tang, Tao-Tao; Lv, Lin-Li; Tang, Ri-Ning; Liu, Hong; Ma, Kun-Ling; Crowley, Steve D.; Liu, Bi-Cheng

    2015-01-01

    Albuminuria contributes to the development and progression of chronic kidney disease by inducing tubulointerstitial inflammation (TI) and fibrosis. However, the exact mechanisms of TI in response to albuminuria are unresolved. We previously demonstrated that NLRP3 and inflammasomes mediate albumin-induced lesions in tubular cells. Here, we further investigated the role of endocytic receptors and lysosome rupture in NLRP3 inflammasome activation. A murine proteinuric nephropathy model was induced by albumin overload as described previously. The priming and activation signals for inflammasome complex formation were evoked simultaneously by albumin excess in tubular epithelial cells. The former signal was dependent on a albumin-triggered NF-κB pathway activation. This process is mediated by the endocytic receptor, megalin and cubilin. However, the silencing of megalin or cubilin inhibited the albumin-induced NLRP3 signal. Notably, subsequent lysosome rupture and the corresponding release of lysosomal hydrolases, especially cathepsin B, were observed in tubular epithelial cells exposed to albumin. Cathepsin B release and distribution are essential for NLRP3 signal activation, and inhibitors of cathepsin B suppressed the NLRP3 signal in tubular epithelial cells. Taken together, our findings suggest that megalin/cubilin and lysosome rupture are involved in albumin-triggered tubular injury and TI. This study provides novel insights into albuminuria-induced TI and implicates the active control of albuminuria as a critical strategy to halt the progression of chronic kidney disease. PMID:26025362

  14. Phase Separation in Solutions of Monoclonal Antibodies

    NASA Astrophysics Data System (ADS)

    Benedek, George; Wang, Ying; Lomakin, Aleksey; Latypov, Ramil

    2012-02-01

    We report the observation of liquid-liquid phase separation (LLPS) in a solution of humanized monoclonal antibodies, IgG2, and the effects of human serum albumin, a major blood protein, on this phase separation. We find a significant reduction of phase separation temperature in the presence of albumin, and a preferential partitioning of the albumin into the antibody-rich phase. We provide a general thermodynamic analysis of the antibody-albumin mixture phase diagram and relate its features to the magnitude of the effective inter-protein interactions. Our analysis suggests that additives (HSA in this report), which have moderate attraction with antibody molecules, may be used to forestall undesirable protein condensation in antibody solutions. Our findings are relevant to understanding the stability of pharmaceutical solutions of antibodies and the mechanisms of cryoglobulinemia.

  15. Process monitor in thermal denaturation of albumin using dynamic speckle method based on wavelet entropy

    NASA Astrophysics Data System (ADS)

    Li, Xinzhong; Chen, Qingdong; Zhen, Zhiqiang; Yan, Haitao; Liu, Huihui; Li, Liben

    2009-11-01

    The process of thermal denaturation of the albumin was investigated using dynamic speckle method based on wavelet entropy and analyzed by light scattering theory. In experiments, the dynamic speckle patterns sequences generated by albumin colloid during denaturing were acquired using a CCD camera. By analyzing the variations of wavelet entropy values of the THSPs (the time history of speckle patterns), the thermal denaturation process of albumin could be divided into two stages. At former heating process, the values of wavelet entropy were bigger; correspondingly, the protein particles were aggregated and flocculated quickly. Conversely, at latter heating process, the wavelet entropy values decreased drastically, which meant there was slow aggregation. According to those, the movement properties of the protein molecule ensemble were analyzed during thermal denaturation of the albumin. The results show that this method is effective to analyze the process of movement and aggregation of protein molecules quantitatively. The experiment proved that this method is an useful tool to investigate the particles motion in solution.

  16. Patterns of the adsorption of bovine serum albumin on carboxymethyl dextran and carboxymethyl cellulose films

    NASA Astrophysics Data System (ADS)

    Paribok, I. V.; Solomyanskii, A. E.; Zhavnerko, G. K.

    2016-02-01

    Patterns of the adsorption of bovine serum albumin on carboxymethyl dextran and carboxymethyl cellulose films are studied by means of microcontact printing, atomic force microscopy, and quartz crystal microbalance. It is shown that both the charge of polysaccharide macromolecules and the technique for deposition of their films onto the surface (via adsorption from a solution or covalent cross-linking) are factors that determine the degree of nonspecific adsorption of the protein on such films.

  17. Changes in methylation pattern of albumin and alpha-fetoprotein genes in developing rat liver and neoplasia.

    PubMed Central

    Vedel, M; Gomez-Garcia, M; Sala, M; Sala-Trepat, J M

    1983-01-01

    To determine whether methylation changes in specific DNA sequences of the albumin and AFP genes are implicated in the modulation of transcriptional activity during rat liver development and neoplasia we have analysed the methylation pattern of C-C-G-G sequences within these genes in DNA isolated from fetal and adult hepatocytes, from adult kidney and from a clonal hepatoma cell line which produces AFP but no albumin. We have assayed for methylation of the internal cytosine of this sequence by using the restriction enzyme isoschizomers HpaII and MspI. 32P-labelled cloned cDNA probes were used to reveal the albumin and AFP gene containing fragments. Genomic subclones of the albumin gene were also utilized as molecular probes to measure quantitatively the level of methylation of 6 specific sites within the albumin gene in the different DNA samples. The results indicate that methylation changes at the sites analysed are not responsible for the changes in gene activity during rat liver development. Further they demonstrate that: 1) extensively methylated genes can be actively transcribed; 2) prominent changes in methylation of specific genes during normal development are not necessarily related to alterations in gene activity. Images PMID:6191280

  18. Stimulation of proximal tubular cell apoptosis by albumin-bound fatty acids mediated by peroxisome proliferator activated receptor-gamma.

    PubMed

    Arici, Mustafa; Chana, Ravinder; Lewington, Andrew; Brown, Jez; Brunskill, Nigel John

    2003-01-01

    In nephrotic syndrome, large quantities of albumin enter the kidney tubule. This albumin carries with it a heavy load of fatty acids to which the proximal tubule cells are exposed at high concentration. It is postulated that exposure to fatty acids in this way is injurious to proximal tubule cells. This study has examined the ability of fatty acids to interact with peroxisome proliferator-activated receptors (PPAR) in primary cultures of human proximal tubule cells. Luciferase reporter assays in transiently transfected human proximal tubule cells were used to show that albumin bound fatty acids and other agonists activate PPARgamma in a dose-dependent manner. One of the consequences of this activation is apoptosis of the cells as determined by changes in cell morphology, evidence of PARP cleavage, and appearance of DNA laddering. Overexpression of PPARgamma in these cells also results in enhanced apoptosis. Both fatty acid-induced PPAR activation and apoptosis in these cells can be blocked by PPAR response element decoy oligonucleotides. Activation of PPARgamma by the specific agonist PGJ(2) is associated with inhibition of cell proliferation, whereas activation by albumin bound fatty acids is accompanied by increased proliferation. However, the net balance of apoptosis/proliferation favors deletion of cells. These results implicate albumin-bound fatty acids as important mediators of tubular injury in nephrosis and provide fresh impetus for pursuit of lipid-lowering strategies in proteinuric renal disease. PMID:12506134

  19. Superhydrophobic Effect on the Adsorption of Human Serum Albumin

    PubMed Central

    Leibner, Evan S.; Barnthip, Naris; Chen, Weinan; Baumrucker, Craig R.; Badding, John V.; Pishko, Michael; Vogler, Erwin A.

    2009-01-01

    Analytical protocol greatly influences measurement of human-serum albumin (HSA) adsorption to commercial expanded polytetrafluororethylene (ePTFE) exhibiting superhydrophobic wetting properties. Degassing of buffer solutions and evacuation of ePTFE adsorbent to remove trapped air immediately prior to contact with protein solutions are shown to be essential. Results obtained with ePTFE as a prototypical superhydrophobic test material suggest that vacuum degassing should be applied in the measurement of protein adsorption to any surface exhibiting superhydrophobicity. Solution depletion quantified using radiometry (I-125 labeled HSA) or electrophoresis yield different measures of adsorption, with nearly four-fold higher surface concentrations of unlabeled HSA measured by the electrophoresis method. This outcome is attributed to the influence of the radiolabel on HSA hydrophilicity which decreases radiolabeled-HSA affinity for a hydrophobic adsorbent in comparison to unlabeled HSA. These results indicate that radiometry underestimates the actual amount of protein adsorbed to a particular material. Removal of radiolabeled HSA adsorbed to ePTFE by 3X serial buffer rinses also shows that the remaining “bound fraction” was about 35% lower than the amount measured by radiometric depletion. This observation implies that measurement of protein bound after surface rinsing significantly underestimates the actual amount of protein concentrated by adsorption into the surface region of a protein-contacting material. PMID:19135420

  20. Controlled delivery of bovine serum albumin from carboxymethyl xanthan microparticles.

    PubMed

    Maiti, Sabyasachi; Ray, Somasree; Sa, Biswanath

    2009-01-01

    Bovine serum albumin (BSA)-loaded carboxymethyl xanthan (CMX) microparticles were prepared following gelation of sodium carboxymethyl xanthan (SCMX) gum with different concentrations (1-5%) of aluminium chloride (AlCl3). The microparticles prepared using 1% AlCl3 were subsequently coated with 0.5% aqueous solution of either SCMX gum or sodium alginate. Both uncoated and coated microparticles were characterized for entrapment efficiency, surface morphology, particle size, in vitro release and protein stability. The uncoated microparticles became non-spherical and the mean diameter was found to increase with increasing AlCl3 concentration. Higher concentration of AlCl3 decreased BSA entrapment efficiency of the uncoated microparticles from 86-61%. Furthermore, BSA entrapment in coated microparticles was found lower (78-79%) than uncoated microparticles prepared using 1% AlCl3. Although, the uncoated microparticles released almost half of its content in NaCl-HCl buffer solution (pH 1.2) in 2 h, the alginate and xanthan coated microparticles did not liberate a substantial amount of entrapped protein within the same period and prolonged the release in PBS solution (pH 7.4) up to 10 and 12 h, respectively. The microparticles released the protein via diffusion and swelling of the polymer matrix. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that BSA integrity was well retained in the CMX microparticles. PMID:19562833

  1. Cu(II) Bis(thiosemicarbazone) Radiopharmaceutical Binding to Serum Albumin: Further Definition of Species-Dependence and Associated Substituent Effects

    PubMed Central

    Basken, Nathan E.; Green, Mark A.

    2009-01-01

    Introduction The Cu-PTSM (pyruvaldehyde bis(N4-methylthiosemicarbazonato)copper(II)) and Cu-ATSM (diacetyl bis(N4-methylthiosemicarbazonato)copper(II)) radiopharmaceuticals exhibit strong, species-dependent binding to the IIA site of human serum albumin (HSA), while the related Cu-ETS (ethylglyoxal bis(thiosemicarbazonato)copper(II)) radiopharmaceutical appears to only exhibit non-specific binding to human and animal serum albumins. Methods To further probe the structural basis for the species-dependence of this albumin binding interaction, protein binding of these three radiopharmaceuticals was examined in solutions of albumin and/or serum from a broader array of mammalian species (rat, sheep, donkey, rabbit, cow, pig, dog, baboon, mouse, cat, elephant). We also evaluated the albumin binding of several copper(II) bis(thiosemicarbazone) chelates offering more diverse substitution of the ligand backbone. Results Cu-PTSM and Cu-ATSM exhibit a strong interaction with HSA that is not apparent with the albumins of other species, while the binding of Cu-ETS to albumin is much less species-dependent. The strong interaction of Cu-PTSM with HSA does not appear to simply correlate with variation, relative to the animal albumins, of a single amino acid lining HSA's IIA site. Those agents that selectively interact with HSA share the common feature of only methyl or hydrogen substitution at the carbon atoms of the diimine fragment of the ligand backbone. Conclusions The interspecies variations in albumin binding of Cu-PTSM and Cu-ATSM are not simply explained by unique amino acid substitutions in the IIA binding pocket of the serum albumins. However, the specific affinity for this region of HSA is disrupted when substituents bulkier than a methyl group appear on the imine carbons of the copper bis(thiosemicarbazone) chelate. PMID:19520290

  2. Surface receptors for serum albumin in group C and G streptococci show three different types of albumin specificity.

    PubMed Central

    Wideback, K; Kronvall, G

    1982-01-01

    A total of 100 bacterial strains were tested for binding uptake of radiolabeled albumin preparations from 15 mammalian species. Three types of surface structures with specific binding sites for albumin were defined. A previously described receptor for albumin was separated into type a in Streptococcus equisimilis strains and in human group G streptococcal strains and type b in bovine group C streptococci. A new type of albumin receptor, type c, was found in Streptococcus dysgalactiae strains, the only receptor type so far with high affinity for bovine serum albumin. Type of albumin receptor correlated with bacterial species. The three receptor types showed high binding capacities; 2 X 10(8) bacterial organisms bound from 5 to 16 micrograms of albumin. All types of albumin receptors were stable to heat treatment at 80 degrees C for 5 min, but susceptible to both pepsin and trypsin treatment. Bacteria-bound albumin preparations were eluted at various concentrations of KSCN, reflecting differences in affinity. Up to 500 micrograms of human fibrinogen or polyclonal human immunoglobulin G had no inhibitory effect on the uptake of albumin, indicating a separate molecular localization of receptors for these proteins. PMID:6295942

  3. Use of 125I- and 51Cr-Labeled Albumin for the Measurement of Gastrointestinal and Total Albumin Catabolism*

    PubMed Central

    Kerr, Robert M.; Bois, John J. Du; Holt, Peter R.

    1967-01-01

    A method for the simultaneous measurement of gastrointestinal protein loss and total albumin turnover entailing the use of a combination of 125iodine- and 51chromium-labeled albumin is described. Albumin turnover was calculated by the measurement of albumin-125I plasma decay and cumulative urinary excretion, and the results obtained agreed closely with previous studies utilizing albumin-131I. Gastrointestinal catabolism was calculated from the rate of fecal excretion of 51Cr and the specific activity of plasma albumin-51Cr, and these data were related to the calculated albumin turnover results. During the period of 6-14 days after administration, the ratio of specific activties of albumin-125I and -51Cr in plasma and in extravascular spaces or gastric and biliary secretions remained almost identical. Fecal excretion of 51Cr was also quite stable at this time. In six normal subjects gastrointestinal catabolism accounted for less than 10% of total albumin catabolism. Excessive gastrointestinal protein losses did not contribute to the low serum albumin in three patients with cirrhosis or in two adults with the nephrotic syndrome. Multiple mechanisms leading to hypoalbuminemia were demonstrated in other subjects with a variety of gastrointestinal disorders. Images PMID:5630419

  4. Mechanisms of albumin uptake by proximal tubular cells.

    PubMed

    Brunskill, N

    2001-01-01

    The likely role of albumin in the induction tubulo-interstitial injury in proteinuria has stimulated considerable interest in the entry of albumin into the proximal tubule and its subsequent uptake by proximal tubular cells. Currently, there is considerable controversy over the degree of glomerular permeability to albumin. After filtration, however, albumin binds to megalin and cubulin, two giant receptors in the apical membrane of proximal tubular cells. Albumin is subsequently re-absorbed by proximal tubular cells by receptor-mediated endocytosis, a process subject to complex regulation. The interaction of albumin with proximal tubule cells also leads to the generation of intracellular signals. The understanding of these pathways may provide important insights into the pathogenesis of renal scarring in proteinuria. PMID:11158855

  5. Investigation of Cu(II) Binding to Bovine Serum Albumin by Potentiometry with an Ion Selective Electrode

    ERIC Educational Resources Information Center

    Jie Liu

    2004-01-01

    A laboratory project that investigates Cu(II) bind to bovine serum albumin (BSA) in an aqueous solution is developed to assist undergraduate students in gaining better understanding of the interaction of ligands with biological macromolecule. Thus, students are introduced to investigation of Cu(II) binding to BSA by potentiometry with the Cu(II)…

  6. Influence of saline infusion on blood-tissue albumin transport.

    PubMed

    Renkin, E M; Rew, K; Wong, M; O'Loughlin, D; Sibley, L

    1989-08-01

    Anesthetized rats were infused with lactated Ringer solution (LR) at constant rate for 30 or 60 min; delivered volume loads ranged from 0.03 to 0.08 ml/g body wt. Controls were given only a sustaining infusion of saline at 0.002 ml.g-1.h-1. Only 7-14% of the LR remained in the plasma at the end of the infusion; 76-88% entered the interstitial compartment, and 7-17% was excreted. The amount of plasma protein lost from the circulation with the extravasated fluid was studied simultaneously by two methods: 1) material balance in the whole animal and 2) changes in 131I-labeled albumin uptake (VA) and water content (VW) in individual tissues. The extravasation of 0.03-0.06 ml fluid/g body wt (75-160% initial plasma volume) did not significantly increase plasma protein extravasation in the whole rat. Nearly all of the sampled tissues of LR-infused rats had higher VW than controls. Tissue VA tended to increase with VW, but the regression slopes (delta VA/delta VW), a measure of the tracer albumin concentration of capillary filtrate relative to plasma, were low; skin, 0.006; paw, 0.018; skeletal muscles, 0.007; heart, 0.057; jejunum, 0.095; ileum, 0.045; cecum, 0.026; and colon, 0.027. These ratios are consistent with the very small loss of total plasma protein observed and attest to high solvent-drag reflection coefficients (sigma approximately equal to 1 - delta VA/delta VW): greater than 0.98 in capillaries of skeletal muscles, skin, and paw and 0.91-0.97 in heart and intestine. PMID:2764135

  7. Pressure solution inhibition in a limestone-chert composite multilayer: Implications for the seismic cycle and fluid flow

    NASA Astrophysics Data System (ADS)

    Petracchini, Lorenzo; Antonellini, Marco; Billi, Andrea; Scrocca, Davide; Trippetta, Fabio; Mollo, Silvio

    2015-04-01

    Pressure solution seams (PSSs) are frequent features in carbonate rocks undergoing tectonic shortening. In particular, pervasive, anticline-axis-parallel, bed-normal PSSs are known to develop during layer-parallel-shortening of (marly) carbonate rocks in fold-thrust belts. These pressure solution features can impact subsequent fracture development, fluid circulation, and strain localization including the seismic cycle. It is here demonstrated that the occurrence of frequent and continuous chert layers may strengthen a limestone sequence and inhibit pressure solution under layer-parallel-shortening. Field observations and laboratory determinations are reported from marly limestone with continuous chert layers of the Scaglia Fm. (Cingoli anticline, northern Apennines, Italy) exhumed from a depth of c. 1 km. In these outcrops, bed-normal solution seams do not occur or they occur only where infrequent chert layers have been shortened by small thrusts. In analogy with laminae-reinforced composite materials, a model is developed explaining the field observations with the strengthening effect of chert in the chert-limestone composite multilayer. During layer-parallel-shortening, the composite multilayer deforms under equal strain boundary conditions. In this situation, the tectonic load is mostly supported by the stiff and frequent chert layers and the strain of the whole chert-limestone composite remains in the elastic field, so that pressure solution seam development is prevented in the limestone beds. Our model may be applied down to a depth of a few kilometers in the upper crust that is relevant for the seismic cycle and fluid flow.

  8. Thermodynamics of Highly Supersaturated Aqueous Solutions of Poorly Water-Soluble Drugs-Impact of a Second Drug on the Solution Phase Behavior and Implications for Combination Products.

    PubMed

    Trasi, Niraj S; Taylor, Lynne S

    2015-08-01

    There is increasing interest in formulating combination products that contain two or more drugs. Furthermore, it is also common for different drug products to be taken simultaneously. This raises the possibility of interactions between different drugs that may impact formulation performance. For poorly water-soluble compounds, the supersaturation behavior may be a critical factor in determining the extent of oral absorption. The goal of the current study was to evaluate the maximum achievable supersaturation for several poorly water-soluble compounds alone, and in combination. Model compounds included ritonavir, lopinavir, paclitaxel, felodipine, and diclofenac. The "amorphous solubility" for the pure drugs was determined using different techniques and the change in this solubility was then measured in the presence of differing amounts of a second drug. The results showed that "amorphous solubility" of each component in aqueous solution is substantially decreased by the second component, as long as the two drugs are miscible in the amorphous state. A simple thermodynamic model could be used to predict the changes in solubility as a function of composition. This information is of great value when developing co-amorphous or other supersaturating formulations and should contribute to a broader understanding of drug-drug physicochemical interactions in in vitro assays as well as in the gastrointestinal tract. PMID:26059413

  9. Photoinduced conformational changes to porphyrin-bound albumin reduces albumin binding to Osteonectin

    NASA Astrophysics Data System (ADS)

    Rozinek, Sarah C.; Thomas, Robert J.; Brancaleon, Lorenzo

    2015-03-01

    Low intensity laser irradiation of photoactive ligands bound non-covalently to proteins can generate a structural change in the proteins, which is detectable spectroscopically. This light induced protein modification could help to study the structure/function relationship in proteins or to prompt non-native protein properties. That is, only if we can determine if and how protein function is effected. Much work has shown small light-induced secondary and tertiary structural changes to albumin have occurred when the protein is bound to a porphyrin such as protoporphyrin IX or meso-tetra(4- sulfonatophenyl)porphyrin (TSPP) and irradiated. This Affinity-Depletion study aims to explore the conformational change of TSPP-bound albumin after visible-light irradiation by testing its ability to bind the biologically relevant albumin receptor, osteonectin. Osteonectin has been covalently attached to magnetic beads, forming an affinity column, but after ten trials (of varied protocol) no substantial albumin-to-osteonectin binding could be achieved.

  10. Implications of long-term land-use change for the hydrology and solute budgets of small catchments in Amazonia

    NASA Astrophysics Data System (ADS)

    Germer, Sonja; Neill, Christopher; Vetter, Tobias; Chaves, Joaquín; Krusche, Alex V.; Elsenbeer, Helmut

    2009-01-01

    SummaryThe replacement of undisturbed tropical forest with cattle pasture has the potential to greatly modify the hydrology of small watersheds and the fluxes of solutes. We examined the fluxes of water, Cl -, NO3--N, SO42--S, NH4+-N, Na +, K +, Mg 2+ and Ca 2+ in different flow paths in ˜1 ha catchments of undisturbed open tropical rainforest and a 20 year-old pasture established from forest in the southwestern Brazilian Amazon state of Rondônia. Storm flow discharge was 18% of incident rainfall in pasture, but only 1% in forest. Quickflow predominated over baseflow in both catchments and in both wet and dry seasons. In the pasture, groundwater and quickflow were important flow paths for the export of all solutes. In the forest, quickflow was important for NO3--N export, but all other solutes were exported primarily by groundwater outflow. Both catchments were sinks for SO42--S and Ca 2+, and sources of Na +. The pasture catchment also lost K + and Mg 2+ because of higher overland flow frequency and volume and to cattle excrement. These results show that forest clearing dramatically influences small watershed hydrology by increasing quickflow and water export to streams. They also indicate that tropical forest watersheds are highly conservative for most solutes but that pastures continue to lose important cations even decades after deforestation and pasture establishment.

  11. The Future Labor Force and Workplace and the Scientific and Engineering Workforce: Implications for Society and Business and Potential Solutions.

    ERIC Educational Resources Information Center

    Lightle, Juliana

    This report examines the future shortages of scientists and engineers and suggests potential solutions to the shortage. The first section presents general demographic data and trends and interprets what this information suggests for the future economy and business in general. The second section considers the supply of physical scientists and…

  12. Implications of Stream Gains and Losses for Hydrologic Turnover and Solute Retention/Transport at the Stream Network Scale

    NASA Astrophysics Data System (ADS)

    Covino, T. P.; McGlynn, B. L.; Mallard, J.

    2010-12-01

    The exchange of water between streams and groundwater can influence streamwater quality, hydrologic mass balances, and attenuate solute export from watersheds. We used conservative tracer injections (chloride, Cl-) across 10 stream reaches to investigate streamwater gains and losses at larger spatial and temporal scales than typically associated with hyporheic exchanges. We found strong relationships between reach discharge, median tracer velocity, and gross hydrologic loss across a broad range of stream types and sizes in the 11.7 km2 Bull Trout Watershed of central ID. We used these empirical relationships to constrain a network model that simulates streamwater gains and losses and subsequent fractional hydrologic turnover across the stream network. We found that variable gains and losses can influence solute signatures across stream networks and lead to increasing dissolved solute concentration inertia moving downstream. These results also elucidate the proportional influence and distance support to stream discharge and solute signatures from runoff generation locations across the stream network and can provide insight into the internal mechanisms that partially control the hydrologic and biogeochemical signals observed at watershed outlets.

  13. Interactions of aptamers with sera albumins

    NASA Astrophysics Data System (ADS)

    Cortez, Célia Martins; Silva, Dilson; Silva, Camila M. C.; Missailidis, Sotiris

    2012-09-01

    The interactions of two short aptamers to human and bovine serum albumins were studied by fluorescence spectroscopic techniques. Intrinsic fluorescence of BSA and HSA were measured by selectively exciting their tryptophan residues. Gradual quenching was observed by titration of both proteins with aptamers. Aptamers are oligonucleic acid or peptide molecules that bind a specific target and can be used for both biotechnological and clinical purposes, since they present molecular recognition properties like that commonly found in antibodies. Two aptamers previously selected against the MUC1 tumour marker were used in this study, one selected for the protein core and one for the glycosylated MUC1. Stern-Volmer graphs were plotted and quenching constants were estimated. Plots obtained from experiments carried out at 25 °C and 37 °C showed the quenching of fluorescence of by aptamers to be a collisional phenomenon. Stern-Volmer constants estimated for HSA quenched by aptamer A were 1.68 × 105 (±5 × 103) M-1 at 37 °C, and 1.37 × 105 (±103) M-1 at 25 °C; and quenched by aptamer B were 1.67 × 105 (±5 × 103) M-1 at 37 °C, and 1.32 × 105 (±103) M-1 at 25 °C. Results suggest that the primary binding site for aptamers on albumin is close to tryptophan residues in sub domain IIA.

  14. Optimization of bovine serum albumin sorption and recovery by hydrogels.

    PubMed

    Gündüz, Ufuk; Tolga, Asli

    2004-07-25

    Aqueous two-phase systems are composed of aqueous solutions of either two water-soluble polymers, usually polyethylene glycol (PEG) and dextran (Dx), or a polymer and a salt, usually PEG and phosphate or sulfate. Partitioning of proteins in such systems provides a powerful method for separating and purifying mixtures of biomolecules by extraction. If one of the phase forming polymers is a crosslinked gel, then the solution-controlled gel sorption may be considered as a modification of aqueous two-phase extraction. Since PEG/dextran systems are widely used in aqueous two-phase extraction and dextran gels (Sephadex) are common chromatographic media, we choose a PEG/dextran gel system as a model system in this study. The partitioning behavior of pure bovine serum albumin (BSA) in PEG/dextran gel systems is investigated to see the effects of variations in PEG and NaCl concentrations on the partition coefficient K. By making use of the Box-Wilson experimental design, K is shown to be maximized at 9.8 (%, w/w) PEG and 0.2 M NaCl concentrations, respectively, as 182. PMID:15177154

  15. Binding and hydrolysis of soman by human serum albumin.

    PubMed

    Li, Bin; Nachon, Florian; Froment, Marie-Thérèse; Verdier, Laurent; Debouzy, Jean-Claude; Brasme, Bernardo; Gillon, Emilie; Schopfer, Lawrence M; Lockridge, Oksana; Masson, Patrick

    2008-02-01

    Human plasma and fatty acid free human albumin were incubated with soman at pH 8.0 and 25 degrees C. Four methods were used to monitor the reaction of albumin with soman: progressive inhibition of the aryl acylamidase activity of albumin, the release of fluoride ion from soman, 31P NMR, and mass spectrometry. Inhibition (phosphonylation) was slow with a bimolecular rate constant of 15 +/- 3 M(-1) min (-1). MALDI-TOF and tandem mass spectrometry of the soman-albumin adduct showed that albumin was phosphonylated on tyrosine 411. No secondary dealkylation of the adduct (aging) occurred. Covalent docking simulations and 31P NMR experiments showed that albumin has no enantiomeric preference for the four stereoisomers of soman. Spontaneous reactivation at pH 8.0 and 25 degrees C, measured as regaining of aryl acylamidase activity and decrease of covalent adduct (pinacolyl methylphosphonylated albumin) by NMR, occurred at a rate of 0.0044 h (-1), indicating that the adduct is quite stable ( t1/2 = 6.5 days). At pH 7.4 and 22 degrees C, the covalent soman-albumin adduct, measured by MALDI-TOF mass spectrometry, was more stable ( t1/2 = 20 days). Though the concentration of albumin in plasma is very high (about 0.6 mM), its reactivity with soman (phosphonylation and phosphotriesterase activity) is too slow to play a major role in detoxification of the highly toxic organophosphorus compound soman. Increasing the bimolecular rate constant of albumin for organophosphates is a protein engineering challenge that could lead to a new class of bioscavengers to be used against poisoning by nerve agents. Soman-albumin adducts detected by mass spectrometry could be useful for the diagnosis of soman exposure. PMID:18163544

  16. Allosteric Ligand Binding and Anisotropic Energy Flow in Albumin

    NASA Astrophysics Data System (ADS)

    Dyer, Brian

    2014-03-01

    Protein allostery usually involves propagation of local structural changes through the protein to a remote site. Coupling of structural changes at remote sites is thought to occur through anisotropic energy transport, but the nature of this process is poorly understood. We have studied the relationship between allosteric interactions of remote ligand binding sites of the protein and energy flow through the structure of bovine serum albumin (BSA). We applied ultrafast infrared spectroscopy to probe the flow of energy through the protein backbone following excitation of a heater dye, a metalloporphyrin or malachite green, bound to different binding sites in the protein. We observe ballistic flow through the protein structure following input of thermal energy into the flexible ligand binding sites. We also observe anisotropic heat flow through the structure, without local heating of the rigid helix bundles that connect these sites. We will discuss the implications of this efficient energy transport mechanism with regard to the allosteric propagation of binding energy through the connecting helix structures.

  17. Influence of albumin and inorganic ions on electrochemical corrosion behavior of plasma electrolytic oxidation coated magnesium for surgical implants

    NASA Astrophysics Data System (ADS)

    Wan, Peng; Lin, Xiao; Tan, LiLi; Li, Lugee; Li, WeiRong; Yang, Ke

    2013-10-01

    Magnesium and its alloys are of great interest for biodegradable metallic devices. However, the degradation behavior and mechanisms of magnesium treated with coating in physiological environment in the presence of organic compound such as albumin have not been elucidated. In this study, the plasma electrolytic oxidation coated magnesium immersed in four different simulated body fluids: NaCl, PBS and with the addition of albumin to investigate the influence of protein and inorganic ions on degradation behavior by electrochemical methods. The results of electrochemical tests showed that aggressive corrosion took place in 0.9 wt.% NaCl solution; whereas albumin can act as an inhibitor, its adsorption impeded further dissolution of the coating. The mechanism was attributed to the synergistic effect of protein adsorption and precipitation of insoluble salts.

  18. The effects of Hespan on serum and lymphatic albumin, globulin, and coagulant protein.

    PubMed Central

    Lucas, C E; Denis, R; Ledgerwood, A M; Grabow, D

    1988-01-01

    The effects of hydroxyethyl starch (Hespan) resuscitation on serum and lymphatic proteins following hemorrhagic shock were studied in 34 splenectomized dogs. Following shock, five randomly assigned treatment groups received the shed blood plus 50 mL/kg of salt solution (RL) or RL with varying concentrations (0.22-1.5 gm/kg) of Hespan. Each dog received 50 ml/kg/d of the test solution for three days after shock. Prothrombin time, partial thromboplastin time, thrombin time, total serum protein, albumin, globulin, and coagulant protein activity of fibrinogen, prothrombin, and factor VIII were measured before shock, at the end of shock, following resuscitation, and on day 3; thoracic duct lymph values were obtained on day 3. Hespan-supplemented resuscitation lowered all serum proteins including albumin, globulin and coagulant proteins; concomitantly, the lymph protein rose after Hespan resuscitation. This decrease in serum proteins and rise in lymph proteins parallels similar results after albumin resuscitation in man and animals and suggests that Hespan induces an oncotically controlled extravascular protein relocation. Further studies on the significance of these findings need to be conducted. PMID:2451485

  19. The role of colloid particles in the albumin-lanthanides interaction: The study of aggregation mechanisms.

    PubMed

    Tikhonova, Tatiana N; Shirshin, Evgeny A; Romanchuk, Anna Yu; Fadeev, Victor V

    2016-10-01

    We studied the interaction between bovine serum albumin (BSA) and lanthanide ions in aqueous solution in the 4.0÷9.5pH range. A strong increase of the solution turbidity was observed at pH values exceeding 6, which corresponds to the formation of Ln(OH)3 nanoparticles, while no changes were observed near the isoelectric point of BSA (pH 4.7). The results of the dynamic light scattering and protein adsorption measurements clearly demonstrated that the observed turbidity enhancement was caused by albumin sorption on the surface of Ln(OH)3 and colloid particles bridging via adsorbed protein molecules. Upon pH increase from 4.5 to 6.5, albumin adsorption on lanthanide colloids was observed, while the following increase of pH from 6.5 to 9.5 led to protein desorption. The predominant role of the electrostatic interactions in the adsorption and desorption processes were revealed in the zeta-potential measurements. No reversibility was observed upon decreasing pH from 9.5 to 4.5 that was suggested to be due to the other interaction mechanisms present in the system. It was shown that while for all lanthanide ions the interaction mechanism with BSA was similar, its manifestation in the optical properties of the system was significantly different. This was interpreted as a consequence of the differences in lanthanides hydrolysis constants. PMID:27419645

  20. Neo-epitopes on methylglyoxal modified human serum albumin lead to aggressive autoimmune response in diabetes.

    PubMed

    Jyoti; Mir, Abdul Rouf; Habib, Safia; Siddiqui, Sheelu Shafiq; Ali, Asif; Moinuddin

    2016-05-01

    Glyco-oxidation of proteins has implications in the progression of diabetes type 2. Human serum albumin is prone to glyco-oxidative attack by sugars and methylglyoxal being a strong glycating agent may have severe impact on its structure and consequent role in diabetes. This study has probed the methylglyoxal mediated modifications of HSA, the alterations in its immunological characteristics and possible role in autoantibody induction. We observed an exposure of chromophoric groups, loss in the fluorescence intensity, generation of AGEs, formation of cross-linked products, decrease in α-helical content, increase in hydrophobic clusters, FTIR band shift, attachment of methylglyoxal to HSA and the formation of N(ε)-(carboxyethyl) lysine in the modified HSA, when compared to the native albumin. MG-HSA was found to be highly immunogenic with additional immunogenicity invoking a highly specific immune response than its native counterpart. The binding characteristics of circulating autoantibodies in type 2 diabetes mellitus (DM) patients showed the generation of anti-MG-HSA auto-antibodies in the these patients, that are preferentially recognized by the modified albumin. We propose that MG induced structural perturbations in HSA, result in the generation of neo-epitopes leading to an aggressive auto-immune response and may contribute to the immunopathogenesis of diabetes type 2 associated complications. PMID:26861824

  1. Calorimetric investigation of diclofenac drug binding to a panel of moderately glycated serum albumins.

    PubMed

    Indurthi, Venkata S K; Leclerc, Estelle; Vetter, Stefan W

    2014-08-01

    Glycation alters the drug binding properties of serum proteins and could affect free drug concentrations in diabetic patients with elevated glycation levels. We investigated the effect of bovine serum albumin glycation by eight physiologically relevant glycation reagents (glucose, ribose, carboxymethyllysine, acetoin, methylglyoxal, glyceraldehyde, diacetyl and glycolaldehyde) on diclofenac drug binding. We used this non-steroidal anti-inflammatory drug diclofenac as a paradigm for acidic drugs with high serum binding and because of its potential cardiovascular risks in diabetic patients. Isothermal titration calorimetry showed that glycation reduced the binding affinity Ka of serum albumin and diclofenac 2 to 6-fold by reducing structural rigidity of albumin. Glycation affected the number of drug binding sites in a glycation reagent dependent manner and lead to a 25% decrease for most reagent, expect for ribose, with decreased by 60% and for the CML-modification, increased the number of binding sites by 60%. Using isothermal titration calorimetry and differential scanning calorimetry we derived the complete thermodynamic characterization of diclofenac binding to all glycated BSA samples. Our results suggest that glycation in diabetic patients could significantly alter the pharmacokinetics of the widely used over-the-counter NSDAI drug diclofenac and with possibly negative implications for patients. PMID:24751671

  2. Production of Molecular Iodine and Tri-iodide in the Frozen Solution of Iodide: Implication for Polar Atmosphere.

    PubMed

    Kim, Kitae; Yabushita, Akihiro; Okumura, Masanori; Saiz-Lopez, Alfonso; Cuevas, Carlos A; Blaszczak-Boxe, Christopher S; Min, Dae Wi; Yoon, Ho-Il; Choi, Wonyong

    2016-02-01

    The chemistry of reactive halogens in the polar atmosphere plays important roles in ozone and mercury depletion events, oxidizing capacity, and dimethylsulfide oxidation to form cloud-condensation nuclei. Among halogen species, the sources and emission mechanisms of inorganic iodine compounds in the polar boundary layer remain unknown. Here, we demonstrate that the production of tri-iodide (I3(-)) via iodide oxidation, which is negligible in aqueous solution, is significantly accelerated in frozen solution, both in the presence and the absence of solar irradiation. Field experiments carried out in the Antarctic region (King George Island, 62°13'S, 58°47'W) also showed that the generation of tri-iodide via solar photo-oxidation was enhanced when iodide was added to various ice media. The emission of gaseous I2 from the irradiated frozen solution of iodide to the gas phase was detected by using cavity ring-down spectroscopy, which was observed both in the frozen state at 253 K and after thawing the ice at 298 K. The accelerated (photo-)oxidation of iodide and the subsequent formation of tri-iodide and I2 in ice appear to be related with the freeze concentration of iodide and dissolved O2 trapped in the ice crystal grain boundaries. We propose that an accelerated abiotic transformation of iodide to gaseous I2 in ice media provides a previously unrecognized formation pathway of active iodine species in the polar atmosphere. PMID:26745029

  3. Immobilization of Bovine Serum Albumin Upon Multiwall Carbon Nanotube for High Speed Humidity Sensing Application.

    PubMed

    Bhattacharya, Sankhya; Sasmal, Milan

    2016-01-01

    We present a high-speed humidity sensor based on immobilization of bovine serum albumin upon multiwall carbon nanotube (IBC). A simple and versatile drop casting technique was employed to make the humidity sensor using novel material IBC at room temperature. IBC was synthesized using easy solution process technique. The working principle of the IBC humidity sensor depends upon the variation of output current or conductance with the exposure of different humidity level. Humidity sensing properties of our device is explained on the basis of charge transfer from water molecules to IBC and bovine serum albumin to multiwall carbon nanotube (MWCNT). Our sensor exhibits faster response time around 1.2 s and recovery time 1.5 s respectively. PMID:26841403

  4. Spectral Fluorescence Properties of an Anionic Oxacarbocyanine Dye in Complexes with Human Serum Albumin

    NASA Astrophysics Data System (ADS)

    Pronkin, P. G.; Tatikolov, A. S.

    2015-07-01

    The spectral fluorescence properties of the anionic oxacarbocyanine dye 3,3'-di-(γ-sulfopropyl)-5,5'-diphenyl-9-ethyloxacarbocyanine betaine (OCC) were studied in solutions and in complexes with human serum albumin (HSA). Interaction with HSA leads to a significant increase in the fluorescence of the dye. We studied quenching of the fluorescence of OCC in a complex with HSA by ibuprofen and warfarin. Data on quenching of fluorescence by ibuprofen indicate binding of the dye to binding site II of subdomain IIIA in the HSA molecule. Synchronous fluorescence spectra of human serum albumin in the presence of OCC showed that complexation with OCC does not lead to appreciable rearrangement of the protein molecule at the binding site.

  5. Dialysate With High Dissolved Hydrogen Facilitates Dissociation of Indoxyl Sulfate From Albumin

    PubMed Central

    Tange, Yoshihiro; Takesawa, Shingo; Yoshitake, Shigenori

    2015-01-01

    Background: Protein-bound toxins such as indoxyl sulfate (IS) are not efficiently removed by conventional hemodialysis (HD). Objectives: To improve the removal of IS, we performed an in vitro study to evaluate the effects of high dissolved hydrogen on the dissociation of IS from albumin using simulated HD. Materials and Methods: Wasted dialysate from peritoneal dialysis was concentrated a hundred times using extracorporeal ultrafiltration method. Dialysate with high dissolved hydrogen was made by mixing concentrated dialysis solution and electrolyzed-reduced water. The amounts of free fractions of IS were determined by high performance liquid chromatography. Results: IS was significantly dissociated from albumin using dialysate with high dissolved hydrogen compared with conventional dialysate (P < 0.05). Conclusions: Effective removal of IS is expected using a dialysate with high dissolved hydrogen. PMID:25883914

  6. Interaction of lipid vesicle with silver nanoparticle-serum albumin protein corona

    NASA Astrophysics Data System (ADS)

    Chen, Ran; Choudhary, Poonam; Schurr, Ryan N.; Bhattacharya, Priyanka; Brown, Jared M.; Chun Ke, Pu

    2012-01-01

    The physical interaction between a lipid vesicle and a silver nanoparticle (AgNP)-human serum albumin (HSA) protein "corona" has been examined. Specifically, the binding of AgNPs and HSA was analyzed by spectrophotometry, and the induced conformational changes of the HSA were inferred from circular dichroism spectroscopy. The fluidity of the vesicle, a model system for mimicking cell membrane, was found to increase with the increased exposure to AgNP-HSA corona, though less pronounced compared to that induced by AgNPs alone. This study offers additional information for understanding the role of physical forces in nanoparticle-cell interaction and has implications for nanomedicine and nanotoxicology.

  7. Spatial Connectivity and Temporal Response of Variable Source Areas (VSAs): Implications for Catchment Scale Water and Solute Mixing

    NASA Astrophysics Data System (ADS)

    Inamdar, S.; Mitchell, M.; McDonnell, J.; McGlynn, B.; Shanley, J.

    2001-05-01

    The significance of variable source areas (VSAs) in storm runoff generation and as loci for mixing of event and pre-event waters has long been recognized. Recent research suggests that VSAs may also play an important role in regulating the export of C and N solutes from catchments. We hypothesize that the spatial distribution of VSAs in the catchment and their connectedness with the stream network is a first order control on the temporal dynamics and expression of water and solutes from the catchment. We examined two contrasting scenarios of VSA distribution: (1) VSAs located lower in the catchment and well connected to the stream network, versus, (2) discrete VSAs located in the upper portions of the catchment and disconnected from the stream network. We evaluated the potential impact of these scenarios on: (a) the timing and peak of event water contributions, and (b) the timing and peak of solute signatures. We hypothesized that if VSAs are well connected to the stream network (Scenario 1), then event water contributions would be distinct and would predominate early on during the rising limb of the hydrograph of stream discharge. In contrast, if VSAs are isolated and disconnected (Scenario 2), then event water contributions would be damped and delayed and possibly continue to be observed through hydrograph recession. We believe solutes such as dissolved organic carbon (DOC), which are primarily flushed from near surface soil horizons, will follow an event water trajectory. We tested these hypotheses for a 135 ha forested headwater catchment in the Adirondack Mountains of New York. Detailed storm runoff and solute data for the catchment are available since 1994. A two-component separation model using base cations (Na, Mg, Ca, and K) was used to partition stormflow discharge into pre-event and event components. Event water contributions were small on the rising limb of the hydrograph, reached their maximum just after the discharge peak, and continued through the

  8. Human serum albumin and its relation with oxidative stress.

    PubMed

    Sitar, Mustafa Erinç; Aydin, Seval; Cakatay, Ufuk

    2013-01-01

    Human serum albumin, a negative acute phase reactant and marker of nutritive status, presents at high concentrations in plasma. Albumin has always been used in many clinical states especially to improve circulatory failure. It has been showed that albumin is involved in many bioactive functions such as regulation of plasma osmotic pressure, binding and transport of various endogenous or exogenous compounds, and finally extracellular antioxidant defenses. Molecules like transferrin, caeruloplasmin, haptoglobin, uric acid, bilirubin, alpha-tocopherol, glucose, and albumin constitute extracellular antioxidant defenses in blood plasma but albumin is the most potent one. Most of the antioxidant properties of albumin can be attributed to its unique biochemical structure. The protein possesses antioxidant properties such as binding copper tightly and iron weakly, scavenging free radicals, e.g., hypochlorous acid (HOCl) and Peroxynitrite (ONOOH) and providing thiol group (-SH). Whether it is chronic or acute, during many pathological conditions, biomarkers of oxidative protein damage increase and this observation continues with considerable oxidation of human serum albumin. There is an important necessity to specify its interactions with Reactive Oxygen Species. Generally, it may lower the availability of pro-oxidants and be preferentially oxidized to protect other macromolecules but all these findings make it necessary that researchers give a more detailed explanation of albumin and its relations with oxidative stress. PMID:24273915

  9. Investigation of bovine serum albumin glycation by THz spectroscopy

    NASA Astrophysics Data System (ADS)

    Cherkasova, Olga P.; Nazarov, Maxim M.; Shkurinov, Alexander P.

    2016-04-01

    Protein glycation is accelerated under hyperglycemic conditions resulting to loss in the structure and biological functions of proteins. The transmission THz spectroscopy has been used for measuring of bovine serum albumin glycation dynamics. It was found that amplitude of albumin THz absorption depends on type of sugars and incubation time.

  10. 21 CFR 866.5040 - Albumin immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Albumin immunological test system. 866.5040 Section 866.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... other body fluids. Measurement of albumin aids in the diagnosis of kidney and intestinal diseases....

  11. 21 CFR 866.5040 - Albumin immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Albumin immunological test system. 866.5040 Section 866.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... other body fluids. Measurement of albumin aids in the diagnosis of kidney and intestinal diseases....

  12. 21 CFR 866.5040 - Albumin immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Albumin immunological test system. 866.5040 Section 866.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... other body fluids. Measurement of albumin aids in the diagnosis of kidney and intestinal diseases....

  13. 21 CFR 866.5040 - Albumin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Albumin immunological test system. 866.5040 Section 866.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... other body fluids. Measurement of albumin aids in the diagnosis of kidney and intestinal diseases....

  14. Effects of glycation on meloxicam binding to human serum albumin

    NASA Astrophysics Data System (ADS)

    Trynda-Lemiesz, Lilianna; Wiglusz, Katarzyna

    2011-05-01

    The current study reports a binding of meloxicam a pharmacologically important new generation, non-steroidal anti-inflammatory drug to glycated form of the human serum albumin (HSA). The interaction of the meloxicam with nonglycated and glycated albumin has been studied at pH 7.4 in 0.05 M sodium phosphate buffer with 0.1 M NaCl, using fluorescence quenching technique and circular dichroism spectroscopy. Results of the present study have shown that the meloxicam could bind both forms of albumin glycated and nonglycated at a site, which was close to the tryptophan residues. Similarly, how for native albumin glycated form has had one high affinity site for the drug with association constants of the order of 10 5 M -1. The glycation process of the HSA significantly has affected the impact of the meloxicam on the binding of other ligands such as warfarin and bilirubin. The affinity of the glycated albumin for bilirubin as for native albumin has been reduced by meloxicam but observed effect was weaker by half (about 20%) compared with nonglycated albumin. In contrast to the native albumin meloxicam binding to glycated form of the protein only slightly affected the binding of warfarin. It seemed possible that the effects on warfarin binding might be entirely attributable to the Lys 199 modification which was in site I.

  15. ALBUMIN CAUSES INCREASED MYOSIN LIGHT CHAIN KINASE EXPRESSION IN ASTROCYTES VIA P38 MITOGEN ACTIVATED PROTEIN KINASE

    PubMed Central

    Rossi, Janet L.; Ralay Ranaivo, Hantamala; Patel, Fatima; Chrzaszcz, MaryAnn; Venkatesan, Charu; Wainwright, Mark S.

    2011-01-01

    Myosin light chain kinase (MLCK) plays an important role in the reorganization of the cytoskeleton leading to disruption of vascular barrier integrity in multiple organs including the blood brain barrier (BBB) after traumatic brain injury (TBI). MLCK has been linked to transforming growth factor (TGF) and rho kinase signaling pathways, but the mechanisms regulating MLCK expression following TBI are not well understood. Albumin leaks into the brain parenchyma following TBI, activates glia and has been linked to TGF-β receptor signaling. We investigated the role of albumin in the increase in MLCK in astrocytes and the signaling pathways involved in this increase. Following midline closed-skull TBI in mice, there was a significant increase in MLCK-immunoreactive (IR) cells and albumin extravasation, which was prevented by treatment with the MLCK inhibitor ML-7. Using immunohistochemical methods, we identified the MCLK-IR cells as astrocytes. In primary astrocytes, exposure to albumin increased both isoforms of MLCK, 130 and 210. Inhibition of the TGF-β receptor partially prevented the albumin-induced increase in both isoforms, which was not prevented by inhibition of smad3. Inhibition of p38 MAPK, but not ERK, JNK or rho kinase also prevented this increase. These results are further evidence of a role of MCLK in the mechanisms of BBB compromise following TBI, and identify astrocytes as a cell type, in addition to endothelium in the BBB which express MLCK. These findings implicate albumin, acting through p38 MAPK, in a novel mechanism by which activation of MLCK following TBI may lead to compromise of the BBB. PMID:21360574

  16. Joint neutron crystallographic and NMR solution studies of Tyr residue ionization and hydrogen bonding: Implications for enzyme-mediated proton transfer

    SciTech Connect

    Michalczyk, Ryszard; Unkefer, Clifford J.; Bacik, John -Paul; Schrader, Tobias E.; Ostermann, Andreas; Kovalevsky, Andrey Y.; McKenna, Robert; Fisher, Suzanne Zoe

    2015-05-05

    Proton transfer is a fundamental mechanism at the core of many enzyme-catalyzed reactions. It is also exquisitely sensitive to a number of factors, including pH, electrostatics, proper active-site geometry, and chemistry. Carbonic anhydrase has evolved a fast and efficient way to conduct protons through a combination of hydrophilic amino acid side chains that coordinate a highly ordered H-bonded water network. This study uses a powerful approach, combining NMR solution studies with neutron protein crystallography, to determine the effect of pH and divalent cations on key residues involved in proton transfer in human carbonic anhydrase. Lastly, the results have broad implications for our understanding of proton transfer and how subtle changes in ionization and H-bonding interactions can modulate enzyme catalysis.

  17. Fluorescence dilution technique for measurement of albumin reflection coefficient in isolated glomeruli.

    PubMed

    Fan, Fan; Chen, Chun Cheng Andy; Zhang, Jin; Schreck, Carlos M N; Roman, Eric A; Williams, Jan M; Hirata, Takashi; Sharma, Mukut; Beard, Daniel A; Savin, Virginia J; Roman, Richard J

    2015-12-15

    This study describes a high-throughput fluorescence dilution technique to measure the albumin reflection coefficient (σAlb) of isolated glomeruli. Rats were injected with FITC-dextran 250 (75 mg/kg), and the glomeruli were isolated in a 6% BSA solution. Changes in the fluorescence of the glomerulus due to water influx in response to an imposed oncotic gradient was used to determine σAlb. Adjustment of the albumin concentration of the bath from 6 to 5, 4, 3, and 2% produced a 10, 25, 35, and 50% decrease in the fluorescence of the glomeruli. Pretreatment of glomeruli with protamine sulfate (2 mg/ml) or TGF-β1 (10 ng/ml) decreased σAlb from 1 to 0.54 and 0.48, respectively. Water and solute movement were modeled using Kedem-Katchalsky equations, and the measured responses closely fit the predicted behavior, indicating that loss of albumin by solvent drag or diffusion is negligible compared with the movement of water. We also found that σAlb was reduced by 17% in fawn hooded hypertensive rats, 33% in hypertensive Dahl salt-sensitive (SS) rats, 26% in streptozotocin-treated diabetic Dahl SS rats, and 21% in 6-mo old type II diabetic nephropathy rats relative to control Sprague-Dawley rats. The changes in glomerular permeability to albumin were correlated with the degree of proteinuria in these strains. These findings indicate that the fluorescence dilution technique can be used to measure σAlb in populations of isolated glomeruli and provides a means to assess the development of glomerular injury in hypertensive and diabetic models. PMID:26447220

  18. Albumin adsorption on to aluminium oxide and polyurethane surfaces.

    PubMed

    Sharma, C P; Sunny, M C

    1990-05-01

    The changes in protein adsorption onto aluminium surfaces coated with different thicknesses of oxide layers were examined. The oxide layers on aluminium substrates were derived by the anodizing technique. Protein adsorption studies were conducted using 125I-labelled albumin and the amount of albumin adsorbed was estimated with the help of a gamma counter. An increase in albumin adsorption was observed on oxide layer coated aluminium surfaces. The effect of anti-Hageman factor on albumin and fibrinogen adsorption on to bare aluminium, oxide layer coated aluminium and bare polyether urethane urea surfaces was also investigated. It was observed that the presence of anti-Hageman factor increased the adsorption of albumin and fibrinogen on to all these substrates. PMID:2383620

  19. Interaction of sulpiride and serum albumin: Modeling from spectrofluorimetric data

    NASA Astrophysics Data System (ADS)

    Fragoso, Viviane Muniz da Silva; Silva, Dilson

    2015-12-01

    We have applied the fluorescence quenching modeling to study the process of interaction of sulpiride with human serum albumin (HSA) and bovine (BSA). Albumin is more abundant protein in blood and it emits fluorescence when excited by 260-295 nm. Sulpiride is an atypical antipsychotic used in the treatment of many psychiatric disorders. As sulpiride is fluorescent, we developed a mathematical model to analyzing the interaction of two fluorescent substances. This model was able to separate the albumin fluorescence from the quencher fluorescence. Results have shown that sulpiride quenches the fluorescence of both albumins by a static process, due to the complex formation drugalbumin. The association constants calculated for sulpiride-HSA was 2.20 (± 0.08) × 104 M-1 at 37° C, and 5.46 (± 0.20) × 104 M-1, 25 ° C, and the primary binding site to sulpiride in the albumin is located closer to the subdomain IB.

  20. Interaction of coffee compounds with serum albumins. Part II: Diterpenes.

    PubMed

    Guercia, Elena; Forzato, Cristina; Navarini, Luciano; Berti, Federico

    2016-05-15

    Cafestol and 16-O-methylcafestol are diterpenes present in coffee, but whilst cafestol is found in both Coffea canephora and Coffea arabica, 16-O-methylcafestol (16-OMC) was reported to be specific of only C. canephora. The interactions of such compounds, with serum albumins, have been studied. Three albumins have been considered, namely human serum albumin (HSA), fatty acid free HSA (ffHSA) and bovine serum albumin (BSA). The proteins interact with the diterpenes at the interface between Sudlow site I and the fatty acid binding site 6 in a very peculiar way, leading to a significant change in the secondary structure. The diterpenes do not displace reference binding drugs of site 2, but rather they enhance the affinity of the site for the drugs. They, therefore, may alter the pharmacokinetic profile of albumin - bound drugs. PMID:26776001

  1. Universal fractal scaling in stream chemistry and its implications for solute transport and water quality trend detection

    PubMed Central

    Kirchner, James W.; Neal, Colin

    2013-01-01

    The chemical dynamics of lakes and streams affect their suitability as aquatic habitats and as water supplies for human needs. Because water quality is typically monitored only weekly or monthly, however, the higher-frequency dynamics of stream chemistry have remained largely invisible. To illuminate a wider spectrum of water quality dynamics, rainfall and streamflow were sampled in two headwater catchments at Plynlimon, Wales, at 7-h intervals for 1–2 y and weekly for over two decades, and were analyzed for 45 solutes spanning the periodic table from H+ to U. Here we show that in streamflow, all 45 of these solutes, including nutrients, trace elements, and toxic metals, exhibit fractal 1/fα scaling on time scales from hours to decades (α = 1.05 ± 0.15, mean ± SD). We show that this fractal scaling can arise through dispersion of random chemical inputs distributed across a catchment. These 1/f time series are non–self-averaging: monthly, yearly, or decadal averages are approximately as variable, one from the next, as individual measurements taken hours or days apart, defying naive statistical expectations. (By contrast, stream discharge itself is nonfractal, and self-averaging on time scales of months and longer.) In the solute time series, statistically significant trends arise much more frequently, on all time scales, than one would expect from conventional t statistics. However, these same trends are poor predictors of future trends—much poorer than one would expect from their calculated uncertainties. Our results illustrate how 1/f time series pose fundamental challenges to trend analysis and change detection in environmental systems. PMID:23842090

  2. Leaching of lead metallurgical slag in citric solutions--implications for disposal and weathering in soil environments.

    PubMed

    Ettler, Vojtech; Komárková, Marie; Jehlicka, Jan; Coufal, Pavel; Hradil, David; Machovic, Vladimír; Delorme, Fabian

    2004-11-01

    Metallurgical slags from primary lead smelting were submitted to a 30-day batch leaching procedure in 20 and 8 mM citric solutions in order to determine the kinetics of release of Pb, Cu, Zn and As. The experiment was coupled with the PHREEQC-2 speciation-solubility modelling and mineralogical study of newly formed products (SEM/EDS, XRD, TEM/EDS and Raman spectrometry). A strong scavenging of metals and metalloids from the 8 mM citric leachate was observed due to the formation of newly formed products. The secondary precipitate consisted of well-developed calcite (CaCO3) crystals and amorphous organo-mineral matrix composed of hydrous ferric oxides and amorphous SiO2. Metals (Pb, Zn, Cu) and arsenic released into the solution were subsequently bound onto the newly formed product (adsorption on oxides) or trapped within the calcite structure (Zn, Mn). Similar scavenging mechanism can be taken into account in real soil systems with lower concentration of citric acid. Then, the covering of slag dumps with a thick soil layer and subsequent re-vegetation might be a possible scenario for slag management on some metallurgical sites. PMID:15488918

  3. Dynamics of Metal Partitioning at the Cell-Solution Interface: Implications for Toxicity Assessment under Growth-Inhibiting Conditions.

    PubMed

    Duval, Jérôme F L; Paquet, Nathalie; Lavoie, Michel; Fortin, Claude

    2015-06-01

    Metal toxicity toward microorganisms is usually evaluated by determining growth inhibition. To achieve a mechanistic interpretation of such toxic effects, the intricate coupling between cell growth kinetics and metal partitioning dynamics at the cell-solution interface over time must be considered on a quantitative level. A formalism is elaborated to evaluate cell-surface-bound, internalized, and extracellular metal fractions in the limit where metal uptake kinetics is controlled by internalization under noncomplexing medium conditions. Cell growth kinetics is tackled using the continuous logistic equation modified to include growth inhibition by metal accumulation to intracellular or cell surface sites. The theory further includes metal-proton competition for adsorption at cell-surface binding sites, as well as possible variation of cell size during exposure to metal ions. The formalism elucidates the dramatic impacts of initial cell concentration on metal bioavailability and toxicity over time, in agreement with reported algae bioassays. It further highlights that appropriate definition of toxicity endpoints requires careful inspection of the ratio between exposure time scale and time scale of metal depletion from bulk solution. The latter depends on metal internalization-excretion rate constants, microorganism growth, and the extent of metal adsorption on nonspecific, transporter, and growth inhibitory sites. As an application of the theory, Cd toxicity in the algae Pseudokirchneriella subcapitata is interpreted from constrained modeling of cell growth kinetics and of interfacial Cd-partitioning dynamics measured under various exposure conditions. PMID:25945520

  4. Viscosity of supercooled aqueous glycerol solutions, validity of the Stokes-Einstein relationship, and implications for cryopreservation.

    PubMed

    Trejo González, José A; Longinotti, M Paula; Corti, Horacio R

    2012-10-01

    The viscosity of supercooled glycerol aqueous solutions, with glycerol mass fractions between 0.70 and 0.90, have been determined to confirm that the Avramov-Milchev equation describes very well the temperature dependence of the viscosity of the binary mixtures including the supercooled regime. On the contrary, it is shown that the free volume model of viscosity, with the parameters proposed in a recent work (He, Fowler, Toner, J. Appl. Phys. 100 (2006) 074702), overestimates the viscosity of the glycerol-rich mixtures at low temperatures by several orders of magnitude. Moreover, the free volume model for the water diffusion leads to predictions of the Stokes-Einstein product, which are incompatible with the experimental findings. We conclude that the use of these free volume models, with parameters obtained by fitting experimental data far from the supercooled and glassy regions, lead to incorrect predictions of the deterioration rates of biomolecules, overestimating their life times in these cryopreservation media. PMID:22609516

  5. Terrestrial reference frame solution with the Vienna VLBI Software VieVS and implication of tropospheric gradient estimation

    NASA Astrophysics Data System (ADS)

    Spicakova, H.; Plank, L.; Nilsson, T.; Böhm, J.; Schuh, H.

    2011-07-01

    The Vienna VLBI Software (VieVS) has been developed at the Institute of Geodesy and Geophysics at TU Vienna since 2008. In this presentation, we present the module Vie_glob which is the part of VieVS that allows the parameter estimation from multiple VLBI sessions in a so-called global solution. We focus on the determination of the terrestrial reference frame (TRF) using all suitable VLBI sessions since 1984. We compare different analysis options like the choice of loading corrections or of one of the models for the tropospheric delays. The effect of atmosphere loading corrections on station heights if neglected at observation level will be shown. Time series of station positions (using a previously determined TRF as a priori values) are presented and compared to other estimates of site positions from individual IVS (International VLBI Service for Geodesy and Astrometry) Analysis Centers.

  6. Experimental investigation and planetary implications of the stability of clathrate hydrates in aqueous solution at icy satellite conditions

    NASA Astrophysics Data System (ADS)

    Dunham, M.; Choukroun, M.; Barmatz, M.; Hodyss, R. P.; Smythe, W. D.

    2012-12-01

    Clathrate hydrates consist of hydrogen-bonded water molecules forming cages in which gas molecules are trapped individually. They are among the favored volatile reservoirs in solar system bodies, and are expected to play an important role in many processes: accretion of volatiles in planetesimals, outgassing on Titan, Enceladus, and comets. Their insulating thermal properties and high mechanical strength also bear important implications for understanding the evolution of icy satellites like Europa. However, the conditions allowing for their formation and/or their dissociation and the release of volatiles to the atmosphere (Titan) or the plumes (Enceladus) are still poorly understood. This is mainly because of a lack of knowledge on the stability of mixed clathrate hydrates in presence of anti-freeze agents such as ammonia. We have developed a high-pressure cryogenic calorimeter to address this deficiency in the literature. This liquid nitrogen - cooled Setaram BT2.15 calorimeter is located at the JPL Ice Physics Laboratory. The temperature range achievable with this instrument is 77-473 K. This calorimeter uses Calvet elements (3D arrays of thermocouples) to measure the heat flow required to follow a predefined heating rate within a sample and a reference cell with a resolution of 0.1 μW. A gas handling system has been designed and fabricated in house to reach pressures up to 100 bars, corresponding to several km depth in icy satellites. The thermodynamic properties of CO2 and CH4 clathrates with ammonia are under investigation, and the results will be used to constrain a statistical thermodynamic model of clathrates for applications to planetary environments. Preliminary results will be shown at the meeting. This work has been conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. Support from the Minnesota Space Grant Consortium, the NASA Outer Planets Research program, and government sponsorship are gratefully

  7. Can biofuels be a solution to climate change? The implications of land use change-related emissions for policy

    PubMed Central

    Khanna, Madhu; Crago, Christine L.; Black, Mairi

    2011-01-01

    Biofuels have gained increasing attention as an alternative to fossil fuels for several reasons, one of which is their potential to reduce the greenhouse gas (GHG) emissions from the transportation sector. Recent studies have questioned the validity of claims about the potential of biofuels to reduce GHG emissions relative to the liquid fossil fuels they are replacing when emissions owing to direct (DLUC) and indirect land use changes (ILUC) that accompany biofuels are included in the life cycle GHG intensity of biofuels. Studies estimate that the GHG emissions released from ILUC could more than offset the direct GHG savings by producing biofuels and replacing liquid fossil fuels and create a ‘carbon debt’ with a long payback period. The estimates of this payback period, however, vary widely across biofuels from different feedstocks and even for a single biofuel across different modelling assumptions. In the case of corn ethanol, this payback period is found to range from 15 to 200 years. We discuss the challenges in estimating the ILUC effect of a biofuel and differences across biofuels, and its sensitivity to the assumptions and policy scenarios considered by different economic models. We also discuss the implications of ILUC for designing policies that promote biofuels and seek to reduce GHG emissions. In a first-best setting, a global carbon tax is needed to set both DLUC and ILUC emissions to their optimal levels. However, it is unclear whether unilateral GHG mitigation policies, even if they penalize the ILUC-related emissions, would increase social welfare and lead to optimal emission levels. In the absence of a global carbon tax, incentivizing sustainable land use practices through certification standards, government regulations and market-based pressures may be a viable option for reducing ILUC. PMID:22482030

  8. Albumin absorption and catabolism by isolated perfused proximal convoluted tubules of the rabbit.

    PubMed Central

    Park, C H; Maack, T

    1984-01-01

    Overall characteristics and kinetics of tubular absorption of albumin (Alb) were studied in isolated perfused proximal convoluted tubules of the rabbit. The fate of absorbed Alb was determined in tubules perfused with low [Alb]. Alb was labeled with tritium by reductive methylation ( [3H3C]Alb). At [Alb] = 0.03 mg/ml, approximately 80% of the absorbed [3H3C]Alb was released to the peritubular bathing solution as catabolic products. Transcellular transport of intact [3H3C]Alb was negligible. Iodoacetate (IAA, 4 mM) inhibited albumin absorption (JAlb) by greater than 95% and fluid reabsorption (JV) by 55%. At [Alb] = 0.1 mg/ml the absorption rate of a derivatized cationic Alb (pI = 8.4) was fivefold greater (P less than 0.01) than that of anionic Alb. Higher cationic [Alb] had deleterious effects on tubular functions. Overall Alb absorption was of high capacity and low affinity (JmaxAlb = 3.7 ng/min per mm tubule length, apparent Michaelis constant (Km) = 1.2 mg/ml). A low capacity system that saturates at near physiological loads was also detected (JmaxAlb = 0.064 ng/min per mm, apparent Km = 0.031 mg/ml). High [Alb] did not alter the rate of endocytic vesicle formation as determined by the tubular uptake of [14C]inulin. Results show that Alb absorption is a saturable process that is inhibited by high IAA concentrations and is affected by the charge of the protein. Absorbed Alb is hydrolyzed by tubular cells and catabolic products are readily released to the peritubular side. The dual kinetics of Alb absorption may be due to a combination of adsorptive endocytosis (low capacity system) and fluid endocytosis of albumin aggregates (high capacity system). Results indicate that albuminuria occurs much before albumin absorption is saturated. The kinetic characteristics of the process of tubular absorption of albumin helps to explain the concomitance of albuminuria, increased renal catabolic rates of albumin, and renal cell deposition of protein absorption droplets in

  9. Evaluating effective reaction rates of kinetically driven solutes in large-scale, anisotropic media: human health risk implications in CO2 leakage

    NASA Astrophysics Data System (ADS)

    Siirila, E. R.; Maxwell, R. M.

    2011-12-01

    The role of high and low hydraulic conductivity (K) regions in heterogeneous, stratified and non-stratified flow fields and the subsequent effect of rate dependent geochemical reactions are investigated with regards to mobilized arsenic from CO2 leakage at a Carbon Capture and Storage (CCS) site. Following the methodology of previous work, human health risk is used as an endpoint for comparison via a two-stage or nested Monte Carlo scheme, explicitly considering joint uncertainty and variability for a hypothetical population of individuals. This study identifies geo-hydrologic conditions where solute reactions are either rate limited (non-reactive), in equilibrium (linear equilibrium assumption, LEA, is appropriate), or are sensitive to time-dependent kinetic reaction rates. Potential interplay between multiple parameters (i.e. positive or negative feedbacks) is shown utilizing stochastic ensembles. In particular, the effect of preferential flow pathways and solute mixing on the field-scale (macrodispersion) and sub-grid (local dispersion) is examined for varying degrees of stratification and regional groundwater velocities. Results show effective reaction rates of kinetic ensembles are dissimilar from LEA ensembles with the inclusion of local dispersion, resulting in an additive tailing effect of the solute plume, a retarded peak time, and an increased cancer risk. This discrepancy between kinetic and LEA ensembles is augmented in highly anisotropic media, especially at intermediate regional groundwater velocities. The distribution, magnitude, and associated uncertainty of cancer risk are controlled by these factors, but are also strongly dependent on the regional groundwater velocity. We demonstrate a higher associated uncertainty of cancer risk in stratified domains is linked to higher aquifer connectivity and less macrodispersion in the flow field. This study has implications in CCS site selection and groundwater driven risk assessment modeling.

  10. Transport of nitrated albumin across continuous vascular endothelium

    PubMed Central

    Predescu, Dan; Predescu, Sanda; Malik, Asrar B.

    2002-01-01

    Because modification of plasma albumin on tyrosine residues generates nitrated albumin (NOA) that may function as a mechanism of nitrogen monoxide clearance from microcirculation, we investigated biochemicaly and morphologically the cell surface binding and the transendothelial transport of NOA. An electron microscopic study was carried out with mouse lungs and hearts perfused in situ with NOA and NOA-Au complexes. The results indicate that NOA-Au can bind to the endothelial cell surface, and its binding can be blocked by albumin plus nitrotyrosine (NO-tyrosine) or abolished by excess NOA. We detected NOA-Au into perivascular spaces as early as 30 sec after the beginning of its perfusion. NOA, unlike native albumin, leaves the vascular lumina via both endothelial caveolae and open junctions. By cross-linking and ligand blotting analysis, we showed that NOA interacted with the same albumin binding proteins of 16–18, 30–32, 60, and 74 kDa as native albumin. ELISA performed on tissue homogenates obtained from the same specimens showed that NOA transport was 2- to 4-fold greater than native albumin. The augmented transendothelial transport of NOA reflects its transcytosis as well as its exit from the microcirculation via open junctions. The increased transport of NOA may serve as an important mechanism that protects a vascular bed against the damaging effects of nitrogen monoxide and peroxynitrite. PMID:12370442

  11. Albumin grafting on biomaterial surfaces using gamma-irradiation

    SciTech Connect

    Kamath, K.R.

    1993-01-01

    Surface modification has been used extensively in various fields to introduce desirable surface properties without affecting the bulk properties of the material. In the area of biomaterials, the approach of surface modification offers an effective alternative to the synthesis of new biomaterials. The specific objective of this study was to modify different biomaterial surfaces by albumin grafting to improve their blood compatibility. The modified surfaces were characterized for surface-induced platelet activation and thrombus formation. This behavior was correlated with the conditions used for grafting. In particular, albumin was functionalized to introduce pendant double bonds into the molecule. The functionalized albumin was covalently attached to various surfaces, such as dimethyldichlorosilane-coated glass, polypropylene, polycarbonate, poly(vinyl chloride), and polyethylene by gamma-irradiation. Platelet adhesion and activation on these surfaces was examined using video microscopy and scanning electron microscopy. The extent of grafting was found to be dependent on the albumin concentration used for adsorption and the gamma-irradiation time. Release of the grafted albumin during exposure to blood was minimal. The albumin-grafted fibers maintained their thromboresistant properties even after storage at elevated temperatures for prolonged time periods. Finally, the approach was used to graft albumin on the PLEXUS Adult Hollow Fiber Oxygenators (Shiley). The blood compatibility of the grafted oxygenators improved significantly when compared to controls.

  12. Investigation of the interaction between naringin and human serum albumin

    NASA Astrophysics Data System (ADS)

    Zhang, Yaheng; Li, Ying; Dong, Lijun; Li, Jiazhong; He, Wenying; Chen, Xingguo; Hu, Zhide

    2008-03-01

    The interaction between naringin and human serum albumin (HSA) has been thoroughly studied by fluorescence quenching technique in combination with UV absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy and molecular modeling method. Under the simulative physiological conditions, fluorescence data revealed the presence of the binding site on HSA and its binding constants ( K) are 1.62 × 10 4, 1.68 × 10 4, 1.72 × 10 4, and 1.79 × 10 4 M -1 at 289, 296, 303, and 310 K, respectively. The alterations of protein secondary structure in the presence of naringin aqueous solution were qualitative and quantitative calculated by the evidence from CD and FT-IR spectroscopes. In addition, according to the Van't Hoff equation, the thermodynamic functions standard enthalpy (Δ H0) and standard entropy (Δ S0) for the reaction were calculated to be 3.45 kJ mol -1 and 92.52 J mol -1 K -1. These results indicated that naringin binds to HSA mainly by a hydrophobic interaction. Furthermore, the displacement experiments confirmed that naringin could bind to the site I of HSA, which was also in agreement with the result of the molecular modeling study.

  13. Albumin contributes to kidney disease progression in Alport syndrome.

    PubMed

    Jarad, George; Knutsen, Russell H; Mecham, Robert P; Miner, Jeffrey H

    2016-07-01

    Alport syndrome is a familial kidney disease caused by defects in the collagen type IV network of the glomerular basement membrane. Lack of collagen-α3α4α5(IV) changes the glomerular basement membrane morphologically and functionally, rendering it leaky to albumin and other plasma proteins. Filtered albumin has been suggested to be a cause of the glomerular and tubular injuries observed at advanced stages of Alport syndrome. To directly investigate the role that albumin plays in the progression of disease in Alport syndrome, we generated albumin knockout (Alb(-/-)) mice to use as a tool for removing albuminuria as a component of kidney disease. Mice lacking albumin were healthy and indistinguishable from control littermates, although they developed hypertriglyceridemia. Dyslipidemia was observed in Alb(+/-) mice, which displayed half the normal plasma albumin concentration. Alb mutant mice were bred to collagen-α3(IV) knockout (Col4a3(-/-)) mice, which are a model for human Alport syndrome. Lack of circulating and filtered albumin in Col4a3(-/-);Alb(-/-) mice resulted in dramatically improved kidney disease outcomes, as these mice lived 64% longer than did Col4a3(-/-);Alb(+/+) and Col4a3(-/-);Alb(+/-) mice, despite similar blood pressures and serum triglyceride levels. Further investigations showed that the absence of albumin correlated with reduced transforming growth factor-β1 signaling as well as reduced tubulointerstitial, glomerular, and podocyte pathology. We conclude that filtered albumin is injurious to kidney cells in Alport syndrome and perhaps in other proteinuric kidney diseases, including diabetic nephropathy. PMID:27147675

  14. Transfer of oleic acid between albumin and phospholipid vesicles

    SciTech Connect

    Hamilton, J.A.; Cistola, D.P.

    1986-01-01

    The net transfer of oleic acid between egg phosphatidylcholine unilamellar vesicles and bovine serum albumin has been monitored by TC NMR spectroscopy and 90% isotopically substituted (1- TC)oleic acid. The carboxyl chemical shifts of oleic acid bound to albumin were different from those for oleic acid in phospholipid vesicles. Therefore, in mixtures of donor particles, the equilibrium distribution of oleic acid was determined from chemical shift and peak intensity data without separation of donor and acceptor particles. In a system containing equal masses of albumin and phospholipid and a stoichiometry of 4-5 mol of oleic acid per mol of albumin, the oleic acid distribution was pH dependent, with greater than or equal to80% of the oleic acid associated with albumin at pH 7.4; association was greater than or equal to90% at pH 8.0. Decreasing the pH below 7.4 markedly decreased the proportion of fatty acid bound to albumin. The distribution was reversible with pH and was independent of whether vesicles or albumin acted as a donor. These data suggest that pH may strongly influence the partitioning of fatty acid between cellular membranes and albumin. The TC NMR method is also advantageous because it provides information about the structural environments of oleic acid bound to albumin or phospholipid, the ionization state of oleic acid in each environment, and the structural integrity of the vesicles. In addition, minimum and maximum limits for the exchange rates of oleic acid among different environments were obtained from the NMR data.

  15. SAM-II Riboswitch Samples at least Two Conformations in Solution in the Absence of Ligand: Implications for Recognition.

    PubMed

    Chen, Bin; LeBlanc, Regan; Dayie, T Kwaku

    2016-02-18

    Conformational equilibria are increasingly recognized as pivotal for biological function. Traditional structural analyses provide a static image of conformers in solution that sometimes present conflicting views. From (13) C and (1) H chemical exchange saturation transfer experiments, in concert with ligation and selective labeling strategies, we show that in the absence of metabolite, a Mg(2+) (0-0.5 mm)-bound apo SAM-II riboswitch RNA exists in a minor (≈10 %) partially closed state that rapidly exchanges with a predominantly (≈90 %) open form with a lifetime of ≈32 ms. The base and sugar (H6,C6, H1',C1') chemical shifts of C43 for the dominant conformer are similar to those of a free CMP, but those of the minor apo species are comparable to shifts of CMPs in helical RNA regions. Our results suggest that these transient, low populated states stabilized by Mg(2+) will likely enhance rapid ligand recognition and, we anticipate, will play potentially ubiquitous roles in RNA signaling. PMID:26800479

  16. Implications of alkaline solutions-induced etching on optical and minority carrier lifetime features of monocrystalline silicon

    NASA Astrophysics Data System (ADS)

    Bachtouli, N.; Aouida, S.; Laajimi, R. Hadj; Boujmil, M. F.; Bessais, B.

    2012-09-01

    In this work, we search to optimize the surface textures of monocrystalline silicon (c-Si) intended to be used in silicon solar cells. For this purpose, we studied the morphology of formed etch hillocks during anisotropic etching of silicon using alkaline solutions based on sodium hydroxide (NaOH), potassium hydroxide (KOH) and tetramethylammonium hydroxide (TMAH). Such treatments lead to the formation of various pyramids-like textures that can be well optimized to improve the photocurrent of c-Si-based solar cells. The produced textures were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), UV-visible optical reflectivity and minority carrier lifetime measurements. These investigations allow evaluating the size and density of the formed pyramidal textures; the apex angles vary between 75° and 82°, while the heights and bases of the pyramids range from a few hundred nanometers to several micrometers. A minimum reflectivity value of about 6% was obtained at specific conditions using NaOH, whereas it was found that the apparent effective minority carrier lifetime (τeff) is sensitive to the injection level (Δn), which shows an apparent increase from 1.2 μs to 2.4 μs for a minority carrier density of about Δn = 21014 cm-3.

  17. African American Participation in Oncology Clinical Trials--Focus on Prostate Cancer: Implications, Barriers, and Potential Solutions.

    PubMed

    Ahaghotu, Chiledum; Tyler, Robert; Sartor, Oliver

    2016-04-01

    In the United States, the incidence and mortality rates of many cancers, especially prostate cancer, are disproportionately high among African American men compared with Caucasian men. Recently, mortality rates for prostate cancer have declined more rapidly in African American versus Caucasian men, but prostate cancer is still the most common cancer and the second leading cause of cancer deaths in African American men in the United States. Compared with Caucasian men, prostate cancer occurs at younger ages, has a higher stage at diagnosis, and is more likely to progress after definitive treatments in African American men. Reasons for racial discrepancies in cancer are multifactorial and potentially include socioeconomic, cultural, nutritional, and biologic elements. In addition to improving access to novel therapies, clinical trial participation is essential to adequately establish the risks and benefits of treatments in African American populations. Considering the disproportionately high mortality rates noted in these groups, our understanding of the natural history and responses to therapies is limited. This review will explore African American underrepresentation in clinical trials with a focus on prostate cancer, and potentially effective strategies to engage African American communities in prostate cancer research. Solutions targeting physicians, investigators, the community, and health care systems are identified. Improvement of African American participation in prostate cancer clinical trials will benefit all stakeholders. PMID:26786562

  18. Self-assembly behaviour of colistin and its prodrug colistin methanesulfonate: implications for solution stability and solubilization

    PubMed Central

    Wallace, Stephanie J.; Li, Jian; Nation, Roger L.; Prankerd, Richard J.; Velkov, Tony; Boyd, Ben J.

    2010-01-01

    Colistin is an amphiphilic antibiotic that has re-emerged into clinical use due to the increasing prevalence of difficult-to-treat Gram-negative infections. The existence of self-assembling colloids in solutions of colistin and its derivative prodrug, colistin methanesulfonate (CMS) was investigated. Colistin and CMS reduced the air-water interfacial tension, and dynamic light scattering (DLS) studies showed the existence of 2.07 ± 0.3 nm aggregates above 1.5 mM for colistin, and of 1.98 ± 0.36 nm aggregates for CMS above 3.5 mM (mean ± SD). Above the respective critical micelle concentrations (CMC) the solubility of azithromycin, a hydrophobic antibiotic, increased approximately linearly with increasing surfactant concentration (5:1 mol ratio colistin:azithromycin), suggestive of hydrophobic domains within the micellar cores. Rapid conversion of CMS to colistin occurred below the CMC (60 % over 48 hr), while conversion above the CMC was less than 1 %. The formation of colistin and CMS micelles demonstrated in this study is the proposed mechanism for solubilization of azithromycin and the concentration-dependent stability of CMS. PMID:20302384

  19. Routes of drug delivery into the nail apparatus: Implications for the efficacy of topical nail solutions in onychomycosis.

    PubMed

    Gupta, Aditya K; Simpson, Fiona C

    2016-01-01

    The route of antifungal drug entry into the nail plate and the underlying nail bed plays an important role in determining the efficacy of therapy. Oral antifungal agents reach the nail bed and nail plate by being ingested and achieving antifungal levels in the blood stream that are well in excess of the minimum inhibitory concentration. The reticular circulation at the distal end of the digit enables the drug to reach the nail bed, the proximal matrix and the lateral nail folds. The drug then diffuses into the proximal, ventral and lateral nail plate. The primary route of drug delivery for topical lacquers is transungual, with drug applied to the dorsal aspect of the nail plate and penetrating to the underlying nail bed. The new topical agents approved in the US for the treatment of onychomycosis are solutions with lower viscosity and increased nail penetration characteristics; therefore, these agents penetrate through the transungual route, but also through the space between the nail plate and the nail bed. This subungual route is an important method of drug delivery and is able to in part circumvent the thickness of the nail plate. PMID:25983025

  20. Chlorpromazine interactions to sera albumins. A study by the quenching of fluorescence

    NASA Astrophysics Data System (ADS)

    Silva, Dilson; Cortez, Célia M.; Louro, Sônia R. W.

    2004-04-01

    Binding of chlorpromazine (CPZ) and hemin (Hmn) to human (HSA) and bovine (BSA) serum albumin was studied by fluorescence quenching technique. Intrinsic fluorescences of BSA and HSA were measured by selectively exciting their tryptophan residues. Gradual quenching was observed by titration of both proteins with CPZ and Hmn. CPZ is a widely used anti-psychosis drug that causes severe side effects and strongly interacts with biomembranes, both in its lipidic and proteic regions. CPZ also interacts with blood components, influences bioavailability, and affects the function of several biomolecules. Albumin plays an important role in the transport and storage of hormones, ions, fatty acids and others substances, including CPZ, affecting the regulation of their plasmatic concentration. Hmn is an important ferric residue of hemoglobin that binds within the hydrophobic region of albumin with great specificity. Hmn added to HSA and BSA solutions at a molar ratio of 1:1 quenched about half of their fluorescence. Stern-Volmer plots obtained from experiments carried out at 25 and 35 °C showed the quenching of fluorescence of HSA and BSA by CPZ to be a collisional phenomenon. Hmn quenches fluorescence by a static process, which specifically indicates the formation of a complex. Our results suggest the prime binding site for CPZ and Hmn on both HSA and BSA to be near tryptophan residues.

  1. Atomic structure and chemistry of human serum albumin

    NASA Technical Reports Server (NTRS)

    He, Xiao M.; Carter, Daniel C.

    1992-01-01

    The three-dimensional structure of human serum albumin has been determined crystallographically to a resolution of 2.8 A. It comprises three homologous domains that assemble to form a heart-shaped molecule. Each domain is a product of two subdomains that possess common structural motifs. The principal regions of ligand binding to human serum albumin are located in hydrophobic cavities in subdomains IIA and ILIA, which exhibit similar chemistry. The structure explains numerous physical phenomena and should provide insight into future pharmacokinetic and genetically engineered therapeutic applications of serum albumin.

  2. Effective ADE models for first-order mobile-immobile solute transport: Limits on validity and modeling implications

    NASA Astrophysics Data System (ADS)

    Hansen, Scott K.

    2015-12-01

    Quasi-1D mobile-immobile transport processes which have exponentially distributed random waiting times in both mobile and immobile states are common in hydrologic models (for example, of transport subject to kinetic sorption). The central limit theorem implies that eventually such transport will be expressible with an effective ADE (i.e. a generalization of the common retardation factor approach with an added Fickian dispersion coefficient accounting for the effect of trapping). Previous works have determined formulae for the value of this coefficient based on the transport properties. However, the time until convergence to Gaussian behavior has not previously been quantified. To this end, exact Green's functions characterizing the transport at all times are derived for the case of pure advection. The Green's functions are expressed in terms of three dimensionless parameters, representing location, time, and capacity coefficient. In the pre-Gaussian regime, a parametric study characterizing concentration profile asymmetry as a function of the capacity coefficient is performed. Next, heuristics are presented in terms of the dimensionless parameters for the time until the effective ADE adequately reflects reality. For strongly retarded solute, the time until effective ADE validity is found inversely proportional to release (e.g., desorption) rate. The nature of the effective dispersion coefficient is examined, and the possibility of large trapping-driven dispersion even in cases where batch experiments would detect negligible trapping is demonstrated. Collectively, these results call into question reliance on retardation factors derived from batch experiments for many practical transport modeling efforts; knowledge of both the trapping and release kinetics appears essential.

  3. Highlighting the implications of selenium dispersion from disposal of Kahota Industrial Triangle area, Islamabad, Pakistan using three-dimension solute transport model.

    PubMed

    Ahmad, Zulfiqar; Kausar, Rubina; Ahmad, Iftikhar

    2010-08-01

    This study highlights the implications of selenium (Se) dispersion in groundwater flow regimes of Kahota Industrial Triangle area located adjacent to the Soan River, Islamabad. Initially, a regional groundwater 3-D flow model has been developed, calibrated to the known observed heads of 24 water wells, verified, and confirmed that convergence has actually arrived to satisfy the steady state condition. Later, the transient simulation was carried out adding in the known recharge, storage factor, porosity, and observed drawdown matched with the simulated drawdown that appears to fall in close agreement with a difference of 0.25 m. As such the steady state groundwater model has facilitated to understand the mechanism of groundwater flow regimes in reference to the implications of selenium dispersion from disposal of Kahota Industrial Triangle area. Thirty-five water samples were collected mainly from the industrial water wells for the evaluation of heavy metals. Selenium being the major contributor of pollution has been short listed to monitor its dispersion using a solute transport model modular three-dimensional transport model (MT3D). Chemical parameters related to selenium characteristics including horizontal and vertical transverse dispersivity/longitudinal dispersivity, effective molecular diffusion coefficient and bulk density of the porous medium of aquifers have been used in MT3D contaminant transport model. MT3D is run for 30 years in steady state condition. As usual first run did not produce the exact field conditions. Therefore, the contaminant transport model is calibrated against the 32 values of observed selenium concentrations in boreholes by minor adjustments in the chemical parameter values. The final calibration has been achieved with residual value of 3.88x10(-5) Kg/m3. Seven hypothetical observation wells are used to monitor the selenium concentrations over a long-term period of time. PMID:19593643

  4. Preparation and characterization of albumin nanoparticles encapsulating curcumin intended for the treatment of breast cancer

    PubMed Central

    Jithan, AV; Madhavi, K; Madhavi, M; Prabhakar, K

    2011-01-01

    Introduction: For the real-time clinical utilization of curcumin (an ayurvedic natural product) to treat breast cancer, its dissolution, rate limited solubility, poor tissue absorption, and extensive in vivo metabolism that leads to its poor systemic bioavailability should be overcome. A polymer-based nanoparticle formulation using bovine serum albumin can increase its aqueous solubility and can achieve protected, sustained, and targeted therapy in breast cancer. Materials and Methods: Desolvation technique was optimized for the preparation of albumin nanoparticles. Particle size, drug release, encapsulation efficiency, drug polymer interaction were the in vitro properties that were determined. Cell culture studies, in vivo pharmacokinetics in rats were used for biological characterization of the formulation. Results: The formulations were successfully prepared using 1:1, 1:2, 1:3, 1:4 drug: polymer ratios and the percent entrapment was found to be 74.76%, 91.01%, 85.36%, 86.42%, respectively, and particle size determined by zetasizer was found to be 225.1, 223.5, 226.3, 228.7 nm, respectively, and in vitro release was sustained for at least one month with drug release of 75.74%, 65.97%, 64.42%, 54%, respectively. The dissolution rate and aqueous solubility of curcumin was enhanced with this formulation. Fourier transform infrared spectroscopy (FTIR) studies demonstrated that the drug was not changed in the formulation during the fabrication process. The proliferation assays in MDA-MB-231 tumor cell lines indicated more effectiveness of the formulation compared to its solution form. In rats, albumin nanoparticles sustained drug release, demonstrated more bioavailability, improved pharmacokinetic properties, and enhanced tissue targetability of the drug. Conclusions: An effective curcumin-albumin nanoparticle formulation was successfully developed using a desolvation technique. PMID:23071931

  5. Interaction between Albumin and Pluronic F127 Block Copolymer Revealed by Global and Local Physicochemical Profiling.

    PubMed

    Neacsu, Maria Victoria; Matei, Iulia; Micutz, Marin; Staicu, Teodora; Precupas, Aurica; Popa, Vlad Tudor; Salifoglou, Athanasios; Ionita, Gabriela

    2016-05-12

    The interaction of human serum albumin (HSA) with amphiphilic block copolymer Pluronic F127 has been investigated by several physical methods. Interest in studying this system stems from a broad range of bioactivities involving both macromolecules. Serum albumins constitute a significant class of proteins in the circulatory system, acting as carriers for a wide spectrum of compounds or assemblies. Pluronic block copolymers have revealed their capacity to ferry a variety of biologically active compounds. Circular dichroism, rheological measurements, and differential scanning microcalorimetry (μDSC) were employed to get insight into the interaction betweeen the two macromolecules. The results reveal that Pluronic F127 induces conformational changes to albumin if it is organized in a micellar form, while albumin influences the self-assembly of Pluronic F127 into micelles or gels. F127 micelles, however, induce smaller conformational changes compared to ionic surfactants. The μDSC thermograms obtained for HSA and/or F127 show that HSA shifts the critical micellar temperature (cmt) to lower values, while concurrently the HSA denaturation behavior is influenced by F127, depending on its concentration. Rheological measurements on solutions of F127 17% have shown that a sol-to-gel transition occurs at higher temperatures in the presence of HSA and the resulting gel is weaker. The global profile on HSA/F127 systems was complemented by local information provided by EPR measurements. A series of X-band EPR experiments was performed with spin probes 4-(N,N'-dimethyl-N-hexadecyl)ammonium-2,2',6,6'-tetramethylpiperidine-1-oxyl iodide (CAT16) and 5-doxyl stearic acid (5-DSA). These spin probes bind to albumin sites and are sensitive to phase transformations in Pluronic block copolymer solutions. For a given F127 concentration, the spin probe binds only to HSA below cmt and migrates to the F127 micelles above cmt. The collective data suggest soft interactions between the

  6. Structural basis of transport of lysophospholipids by human serum albumin

    SciTech Connect

    Guo, Shihui; Shi, Xiaoli; Yang, Feng; Chen, Liqing; Meehan, Edward J.; Bian, Chuanbing; Huang, Mingdong

    2010-10-08

    Lysophospholipids play important roles in cellular signal transduction and are implicated in many biological processes, including tumorigenesis, angiogenesis, immunity, atherosclerosis, arteriosclerosis, cancer and neuronal survival. The intracellular transport of lysophospholipids is through FA (fatty acid)-binding protein. Lysophospholipids are also found in the extracellular space. However, the transport mechanism of lysophospholipids in the extracellular space is unknown. HSA (human serum albumin) is the most abundant carrier protein in blood plasma and plays an important role in determining the absorption, distribution, metabolism and excretion of drugs. In the present study, LPE (lysophosphatidylethanolamine) was used as the ligand to analyse the interaction of lysophospholipids with HSA by fluorescence quenching and crystallography. Fluorescence measurement showed that LPE binds to HSA with a K{sub d} (dissociation constant) of 5.6 {micro}M. The presence of FA (myristate) decreases this binding affinity (K{sub d} of 12.9 {micro}M). Moreover, we determined the crystal structure of HSA in complex with both myristate and LPE and showed that LPE binds at Sudlow site I located in subdomain IIA. LPE occupies two of the three subsites in Sudlow site I, with the LPE acyl chain occupying the hydrophobic bottom of Sudlow site I and the polar head group located at Sudlow site I entrance region pointing to the solvent. This orientation of LPE in HSA suggests that HSA is capable of accommodating other lysophospholipids and phospholipids. The study provides structural information on HSA-lysophospholipid interaction and may facilitate our understanding of the transport and distribution of lysophospholipids.

  7. Protein adsorption on low temperature isotropic carbon. III. Isotherms, competitivity, desorption and exchange of human albumin and fibrinogen.

    PubMed

    Feng, L; Andrade, J D

    1994-04-01

    In this paper we consider the adsorption of albumin and fibrinogen on low temperature isotropic carbon (LTIC). A subsequent paper considers the adsorption of other plasma proteins [Feng L, Andrade JD, Colloids and Surfaces (in press)]. Carbon fragments and silica plates were used as adsorbents. Adsorption was carried out by incubating the adsorbents in solutions of 125I-labelled and unlabelled proteins (single component system), or with buffer-diluted human plasma (multicomponent system). Adsorbed proteins then underwent displacement by buffer, by single protein solutions or by dilute plasma. Results show that the LTIC substrate adsorbs a large amount of proteins before saturation, which may be due to multilayer adsorption. LTIC also irreversibly holds adsorbed proteins against the exchange agents used; little adsorbed proteins can be displaced, even after a very short adsorption time. There is no preferential adsorption for either albumin or fibrinogen on LTIC from their binary solutions, suggesting that both proteins have high affinities for the surface. Such strong interactions between LTIC and proteins are not attributed to electrostatic interactions. On the other hand, protein adsorption on the silica surface is selective and reversible, with a much higher affinity for fibrinogen than albumin and an even higher affinity for some other plasma proteins. The paper also discusses the effect of sequential protein addition to a solution on the surface concentration and suppression of adsorption of both proteins in the presence of other plasma proteins. A very important conclusion is that the LTIC surface is very active towards proteins adsorption. PMID:8061122

  8. Importance of albumin binding in the assay for carnitine palmitoyltransferase.

    PubMed Central

    McCormick, K; Notar-Francesco, V J

    1983-01-01

    Alterations in the long-chain acyl-CoA binding to albumin in the carnitine palmitoyltransferase (CPT) assay appreciably affect the reaction at commonly used substrate concentrations. Since in the CPT assay the latter are typically well below saturation or Vmax. values, the measured enzyme activity depends on both the absolute quantity of albumin in the CPT assay and any biochemical modification of its binding. The present study verifies the striking dependence of the K0.5 for palmitoyl-CoA on albumin and the misleading 'activation' of the enzyme by compounds that also avidly bind to albumin. In assessing the intracellular physiological relevance of any modifier of CPT, the effects of protein binding in the assay assume particular importance. Indeed, any compound that alters CPT activity may do so, not directly, but as an assay artifact changing the free or unbound substrate concentrations. PMID:6661210

  9. 99M-technetium labeled macroaggregated human serum albumin pharmaceutical

    DOEpatents

    Winchell, Harry S.; Barak, Morton; Van Fleet, III, Parmer

    1977-05-17

    A reagent comprising macroaggregated human serum albumin having dispersed therein particles of stannous tin and a method for instantly making a labeled pharmaceutical therefrom, are disclosed. The labeled pharmaceutical is utilized in organ imaging.

  10. Development of FET-type albumin sensor for diagnosing nephritis.

    PubMed

    Park, Keun-Yong; Sohn, Young-Soo; Kim, Chang-Kyu; Kim, Hong-Seok; Bae, Young-Seuk; Choi, Sie-Young

    2008-07-15

    An albumin biosensor based on a potentiometric measurement using Biofield-effect-transistor (BioFET) has been designed and fabricated, and its characteristics were investigated. The BioFET was fabricated using semiconductor integrated circuit (IC) technology. The gate surface of the BioFET was chemically modified by newly developed self-assembled monolayer (SAM) synthesized by a thiazole benzo crown ether ethylamine (TBCEA)-thioctic acid to immobilize anti-albumin. SAM formation, antibody immobilization, and antigen-antibody interaction were verified using surface plasmon resonance (SPR). The output voltage changes of the BioFET with respect to various albumin concentrations were obtained. Quasi-reference electrode (QRE) and reference FET (ReFET) has been integrated with the BioFET, and its output characteristic was investigated. The results demonstrate the feasibility of the BioFET as the albumin sensor for diagnosing nephritis. PMID:18440216

  11. A high-capacity hydrophobic adsorbent for human serum albumin.

    PubMed

    Belew, M; Peterson, E A; Porath, J

    1985-12-01

    A simple method, based on salting out hydrophobic interaction chromatography, for the efficient removal of trace amounts of serum albumin from partially purified protein preparations is described. The method is also successfully applied for the purification of albumin from Cohn fraction IV, a by-product obtained from the commercial fractionation of human serum proteins by the ethanol precipitation procedure. About 70% of the adsorbed albumin can be eluted by buffer of low ionic strength and can thus be lyophilized directly, if required. The adsorbent can be used for several cycles of adsorption and desorption without affecting its selectivity or capacity. Its adsorption properties and capacity for serum albumin are compared with those of the commercially available adsorbent Blue Sepharose CL-6B. PMID:3879424

  12. Molecular interactions between albumin and proximal tubular cells.

    PubMed

    Brunskill, N J

    1998-01-01

    In glomerular diseases the filtration of excess proteins into the proximal tubule, together with their subsequent reabsorption may represent an important pathological mechanism underlying progressive renal scarring. The most prominent protein in glomerular filtrate, albumin, is reabsorbed by receptor-mediated endocytosis by proximal tubular cells. It binds both to scavenger-type receptors and to megalin in the proximal tubule. Some of these receptors appear to be shared with other cell types, particularly endothelial cells. The endocytic uptake of albumin is subjected to complex hormonal and enzymatic regulation. In addition to being reabsorbed in the proximal tubule, albumin may act as a signalling molecule in these cells, and may induce the expression of numerous pro-inflammatory genes. Modulation of the interaction of albumin with proximal tubular cells may eventually prove to be of therapeutic importance in the treatment of renal diseases. PMID:9807019

  13. Binding of dapsone and its analogues to human serum albumin.

    PubMed

    Karp, W B; Subramanyam, S B; Robertson, A F

    1985-06-01

    The binding of dapsone, 4,4'-sulfonylbis(aniline)(1), and its diacetylated derivative, 4,4"'-sulfonylbis(acetanilide)(2), to human serum albumin is reported. To assess the ability of these compounds to displace 4'-[(4-aminophenyl)sulfonyl]acetanilide (3) from albumin, a dialysis rate technique was used. Competition for the bilirubin binding site on albumin was measured with the peroxidase assay. Compounds 1 and 2 strongly displaced both 3 and bilirubin from human serum albumin. The association constants for 1 and 2 with respect to bilirubin binding were 1.29 X 10(3) and 1.15 X 10(4) M-1, respectively. These results suggest that the binding site for 3 and the bilirubin binding site are similar with respect to 1 and 2 and that the binding of dapsone and its derivatives probably does not involve the amino function. PMID:4020658

  14. In vivo albumin labeling and lymphatic imaging

    PubMed Central

    Wang, Yu; Lang, Lixin; Huang, Peng; Wang, Zhe; Jacobson, Orit; Kiesewetter, Dale O.; Ali, Iqbal U.; Teng, Gaojun; Niu, Gang; Chen, Xiaoyuan

    2015-01-01

    The ability to accurately and easily locate sentinel lymph nodes (LNs) with noninvasive imaging methods would assist in tumor staging and patient management. For this purpose, we developed a lymphatic imaging agent by mixing fluorine-18 aluminum fluoride-labeled NOTA (1,4,7-triazacyclononane-N,N',N''-triacetic acid)-conjugated truncated Evans blue (18F-AlF-NEB) and Evans blue (EB) dye. After local injection, both 18F-AlF-NEB and EB form complexes with endogenous albumin in the interstitial fluid and allow for visualizing the lymphatic system. Positron emission tomography (PET) and/or optical imaging of LNs was performed in three different animal models including a hind limb inflammation model, an orthotropic breast cancer model, and a metastatic breast cancer model. In all three models, the LNs can be distinguished clearly by the apparent blue color and strong fluorescence signal from EB as well as a high-intensity PET signal from 18F-AlF-NEB. The lymphatic vessels between the LNs can also be optically visualized. The easy preparation, excellent PET and optical imaging quality, and biosafety suggest that this combination of 18F-AlF-NEB and EB has great potential for clinical application to map sentinel LNs and provide intraoperative guidance. PMID:25535368

  15. In vivo albumin labeling and lymphatic imaging.

    PubMed

    Wang, Yu; Lang, Lixin; Huang, Peng; Wang, Zhe; Jacobson, Orit; Kiesewetter, Dale O; Ali, Iqbal U; Teng, Gaojun; Niu, Gang; Chen, Xiaoyuan

    2015-01-01

    The ability to accurately and easily locate sentinel lymph nodes (LNs) with noninvasive imaging methods would assist in tumor staging and patient management. For this purpose, we developed a lymphatic imaging agent by mixing fluorine-18 aluminum fluoride-labeled NOTA (1,4,7-triazacyclononane-N,N',N''-triacetic acid)-conjugated truncated Evans blue ((18)F-AlF-NEB) and Evans blue (EB) dye. After local injection, both (18)F-AlF-NEB and EB form complexes with endogenous albumin in the interstitial fluid and allow for visualizing the lymphatic system. Positron emission tomography (PET) and/or optical imaging of LNs was performed in three different animal models including a hind limb inflammation model, an orthotropic breast cancer model, and a metastatic breast cancer model. In all three models, the LNs can be distinguished clearly by the apparent blue color and strong fluorescence signal from EB as well as a high-intensity PET signal from (18)F-AlF-NEB. The lymphatic vessels between the LNs can also be optically visualized. The easy preparation, excellent PET and optical imaging quality, and biosafety suggest that this combination of (18)F-AlF-NEB and EB has great potential for clinical application to map sentinel LNs and provide intraoperative guidance. PMID:25535368

  16. Complexes of dendrimers with bovine serum albumin.

    PubMed

    Mandeville, J S; Tajmir-Riahi, H A

    2010-02-01

    We report the complexation of bovine serum albumin (BSA) with several dendrimers of different compositions mPEG-PAMAM (G3), mPEG-PAMAM (G4), and PAMAM (G4) at physiological conditions using constant protein concentration and various dendrimer contents. FTIR, CD, and fluorescence spectroscopic methods were used to analyze polymer binding mode, the binding constant, and the effects of dendrimer complexation on BSA stability and conformation. Structural analysis showed that dendrimers bind BSA via hydrophilic and hydrophobic interactions with a number of bound polymers (n): 1.30 for mPEG-PAMAM-G3, 1.30 for mPEG-PAMAM-G4, and 1.0 for PAMAM-G4. The polymer-BSA binding constants were K(mPEG-G3) = 5.0 (+/-0.8) x 10(3) M(-1), K(mPEG-G4) = 1.0 (+/-0.3) x 10(4) M(-1), and K(PAMAM-G4) = 1.1 (+/-0.4) x 10(4) M(-1). Dendrimer binding altered BSA conformation with a major reduction of alpha-helix and an increase in random coil and turn structures, indicating a partial protein unfolding. PMID:20085247

  17. Photophysical investigations of squaraine and cyanine dyes and their interaction with bovine serum albumin

    NASA Astrophysics Data System (ADS)

    Saikiran, M.; Sato, D.; Pandey, S. S.; Kato, T.

    2016-04-01

    A model far-red sensitive symmetrical squaraine dye (SQ-3) and unsymmetrical near infra-red sensitive cyanine dye (UCD-1) bearing direct–COOH functionalized indole ring were synthesized, characterized and subjected to photophysical investigations including their interaction with bovine serum albumin (BSA) as a model protein in phosphate buffer solution (PBS). Both of the dyes exhibit strong interaction with BSA in phosphate buffer with high apparent binding constant. A judicious tuning of hydrophobic main backbone with reactive functionality for associative interaction with active site of BSA has been found to be necessary for BSA detection in PBS.

  18. THE SECRETORY PATHWAYS OF RAT SERUM GLYCOPROTEINS AND ALBUMIN

    PubMed Central

    Redman, Colvin M.; Cherian, M. George

    1972-01-01

    These studies compare the secretory pathways of newly formed rat serum glycoproteins and albumin by studying their submicrosomal localization at early times after the beginning of their synthesis and also by determining the submicrosomal site of incorporation of N-acetylglucosamine, mannose, galactose, and leucine into protein. N-acetylglucosamine, mannose, and galactose were only incorporated in vitro into proteins from membrane-attached polysomes and not into proteins from free polysomes. Mannose incorporation occurred in the rough endoplasmic reticulum, was stimulated by puromycin but not by cycloheximide, and 90% of the mannose-labeled protein was bound to the membranes. Galactose incorporation, by contrast, occurred in the smooth microsome fraction and 89% of the radioactive protein was in the cisternae. Albumin was mostly recovered (98%) in the cisternae, with negligible amounts in the membranes. To determine whether the radio-active sugars were being incorporated into serum proteins or into membrane protein, the solubilized in vivo-labeled proteins were treated with specific antisera to rat serum proteins or to albumin. Immunoelectrophoresis of the 14C-labeled leucine membrane and cisternal proteins showed that the membranes contained radioactive serum glycoprotein but no albumin, while the cisternal fraction contained all of the radioactive albumin and some glycoproteins. The results indicate that newly formed serum glycoproteins remain attached to the membranes of the rough endoplasmic reticulum after they are released from the membrane-attached polysomes, while albumin passes directly into the cisternae. PMID:5057975

  19. Measurement of lung fluid volumes and albumin exclusion in sheep

    SciTech Connect

    Pou, N.A.; Roselli, R.J.; Parker, R.E.; Clanton, J.A.; Harris, T.R. )

    1989-10-01

    A radioactive tracer technique was used to determine interstitial diethylenetriaminepentaacetic acid (DTPA) and albumin distribution volume in sheep lungs. {sup 125}I- and/or {sup 131}I-labeled albumin were injected intravenously and allowed to equilibrate for 24 h. {sup 99m}Tc-labeled DTPA and {sup 51}Cr-labeled erythrocytes were injected and allowed to equilibrate (2 h and 15 min, respectively) before a lethal dose of thiamylal sodium. Two biopsies (1-3 g) were taken from each lung and the remaining tissue was homogenized for wet-to-dry lung weight and volume calculations. Estimates of distribution volumes from whole lung homogenized samples were statistically smaller than biopsy samples for extravascular water, interstitial {sup 99m}Tc-DTPA, and interstitial albumin. The mean fraction of the interstitium (Fe), which excludes albumin, was 0.68 +/- 0.04 for whole lung samples compared with 0.62 +/- 0.03 for biopsy samples. Hematocrit may explain the consistent difference. To make the Fe for biopsy samples match that for homogenized samples, a mean hematocrit, which was 82% of large vessel hematocrit, was required. Excluded volume fraction for exogenous sheep albumin was compared with that of exogenous human albumin in two sheep, and no difference was found at 24 h.

  20. Cell cytotoxicity and serum albumin binding capacity of the morin-Cu(ii) complex and its effect on deoxyribonucleic acid.

    PubMed

    Roy, Atanu Singha; Samanta, Sintu Kumar; Ghosh, Pooja; Tripathy, Debi Ranjan; Ghosh, Sudip Kumar; Dasgupta, Swagata

    2016-08-16

    The dietary components, flavonoids, are important for their anti-oxidant properties and the ability to act as metal ion chelators. The characterization of the morin-Cu(ii) complex is executed using elemental analysis, FTIR and mass spectroscopy. DNA cleaving and cell cytotoxicity properties followed by serum albumin binding have been investigated in this report. The morin-Cu(ii) complex was found to cleave plasmid pBR322 DNA via an oxidative pathway as revealed by agarose gel based assay performed in the presence of some scavengers and reactive oxygen species. The breaking of the deoxyribose ring of calf thymus DNA (ct-DNA) was also confirmed by the formation of thiobarbituric acid reacting species (TBARS) between thiobarbituric acid and malonaldehyde. The morin-Cu(ii) complex is able to inhibit the growth of human HeLa cells. Fluorescence studies revealed that the morin-Cu(ii) complex can quench the intrinsic fluorescence of serum albumins (SAs) via a static quenching method. The binding constants were found to be in the order of 10(5) M(-1) and observed to increase with temperature. Both ΔH° and ΔS° are positive for the binding of the morin-Cu(ii) complex with serum albumins which indicated the presence of hydrophobic forces. Site-selectivity studies reveal that the morin-Cu(ii) complex binds to both site 1 (subdomain IIA) and site 2 (subdomain IIIA) of human serum albumin (HSA) and bovine serum albumin (BSA). Circular dichroism (CD) studies showed the structural perturbation of SAs during binding with the morin-Cu(ii) complex. The results from binding studies confirmed that after complexation with the Cu(ii) ion, morin alters its mode of interaction with SAs which could have differential implications on its other biological and pharmaceutical properties. PMID:27345944

  1. Fluorescence lifetime measurements of native and glycated human serum albumin and bovine serum albumin

    NASA Astrophysics Data System (ADS)

    Joshi, Narahari V.; Joshi, Virgina O. d.; Contreras, Silvia; Gil, Herminia; Medina, Honorio; Siemiarczuk, Aleksander

    1999-05-01

    Nonenzymatic glycation, also known as Maillard reaction, plays an important role in the secondary complications of the diabetic pathology and aging, therefore, human serum albumin (HSA) and bovine serum albumin (BSA) were glycated by a conventional method in our laboratory using glucose as the glycating agent. Fluorescence lifetime measurements were carried out with a laser strobe fluorometer equipped with a nitrogen/dye laser and a frequency doubler as a pulsed excitation source. The samples were excited at 295 nm and the emission spectra were recorded at 345 nm. The obtained decay curves were tried for double and triple exponential functions. It has been found that the shorter lifetime increases for glycated proteins as compared with that of the native ones. For example, in the case of glycated BSA the lifetime increased from 1.36 ns to 2.30 ns. Similarly, for HSA, the lifetime increases from 1.58 ns to 2.26 ns. Meanwhile, the longer lifetime changed very slightly for both proteins (from 6.52 ns to 6.72 ns). The increase in the lifetime can be associated with the environmental effect; originated from the attachment of glucose to some lysine residues. A good example is Trp 214 which is in the cage of Lys 225, Lys 212, Lys 233, Lys 205, Lys 500, Lys 199 and Lys 195. If fluorescence lifetime technique is calibrated and properly used it could be employed for assessing glycation of proteins.

  2. Interaction of ergosterol with bovine serum albumin and human serum albumin by spectroscopic analysis.

    PubMed

    Cheng, Zhengjun

    2012-10-01

    This study was designed to examine the interactions of ergosterol with bovine serum albumin (BSA) and human serum albumin (HSA) under physiological conditions with the drug concentrations in the range of 2.99-105.88 μM and the concentration of proteins was fixed at 5.0 μM. The analysis of emission spectra quenching at different temperatures revealed that the quenching mechanism of HSA/BSA by ergosterol was the static quenching. The number of binding sites n and the binding constants K were obtained at various temperatures. The distance r between ergosterol and HSA/BSA was evaluated according to Föster non-radioactive energy transfer theory. The results of synchronous fluorescence, 3D fluorescence, FT-IR, CD and UV-Vis absorption spectra showed that the conformations of HSA/BSA altered in the presence of ergosterol. The thermodynamic parameters, free energy change (ΔG), enthalpy change (ΔH) and entropy change (ΔS) for BSA-ergosterol and HSA-ergosterol systems were calculated by the van't Hoff equation and discussed. Besides, with the aid of three site markers (for example, phenylbutazone, ibuprofen and digitoxin), we have reported that ergosterol primarily binds to the tryptophan residues of BSA/HSA within site I (subdomain II A). PMID:22733490

  3. Enantioselective separation of chiral arylcarboxylic acids on an immobilized human serum albumin chiral stationary phase.

    PubMed

    Andrisano, V; Booth, T D; Cavrini, V; Wainer, I W

    1997-01-01

    A series of 12 chiral arylcarboxylic acids were chromatographed on an immobilized human serum albumin chiral stationary phase (HSA-CSP). The effects of solute structure on chromatographic retentions and enantioselective separations were examined by linear regression analysis and the construction of quantitative structure-enantioselective retention relationships. Competitive displacement studies were also conducted using R-ibuprofen as the displacing agent. The results indicate that the enantioselective retention of the solutes takes place at the indole-benzodiazepine site (site II) on the HSA molecule and that chiral recognition is affected by the hydrophobicity and steric volume of the solutes. The displacement studies also identified a cooperative allosteric interaction induced by the binding of R-ibuprofen to site II. PMID:9134695

  4. Coordinate secretion of mouse alphafetoprotein, mouse albumin and rat albumin by mouse hepatoma-rat hepatoma hybrid cells.

    PubMed

    Cassio, D; Hassoux, R; Dupiers, M; Uriel, J; Weiss, M C

    1980-09-01

    Mouse heptoma cells that secrete large amounts of alpha-fetoprotein (AFP) and albumin have been crossed with rat hepatoma cells that secret only albumin, and in relatively small amounts, to investigate the influence of each parental genome upon the expression of serum proteins. All of the ten independent hybrid clones examined produce mouse AFP and both mouse and rat albumin; none produces rat AFP. The absence of production of rat AFP by the hybrids suggests that different mechanisms are involved in the initiation and in the maintenance of expression of this function. The secretion of the three proteins by the hybrid cells is coordinate: Whatever the growth phase (exponential or stationary) and irrespective of the amounts produced over a wide range, the ratio secreted of mouse AFP to mouse albumin is near to one, and that of mouse albumin to rat albumin is near to five. In addition, even though the pattern of protein secretion during the growth cycle of hybrid cells is different from those of both parents, the products of both parental genomes conform to the new hybrid pattern. Finally, some hybrids secrete less of the proteins with increasing numbers of cell generations, yet all three continue to be secreted in coordinate fashion. Since the rates of secretion of serum proteins probably reflect their rates of synthesis, we conclude that coordinate secretion indicates coordinate synthesis, and may reflect coordinate transcription of the relevant genes. PMID:6158520

  5. Sulforhodamine B interacts with albumin to lower surface tension and protect against ventilation injury of flooded alveoli.

    PubMed

    Kharge, Angana Banerjee; Wu, You; Perlman, Carrie E

    2015-02-01

    In the acute respiratory distress syndrome, alveolar flooding by proteinaceous edema liquid impairs gas exchange. Mechanical ventilation is used as a supportive therapy. In regions of the edematous lung, alveolar flooding is heterogeneous, and stress is concentrated in aerated alveoli. Ventilation exacerbates stress concentrations and injuriously overexpands aerated alveoli. Injury degree is proportional to surface tension, T. Lowering T directly lessens injury. Furthermore, as heterogeneous flooding causes the stress concentrations, promoting equitable liquid distribution between alveoli should, indirectly, lessen injury. We present a new theoretical analysis suggesting that liquid is trapped in discrete alveoli by a pressure barrier that is proportional to T. Experimentally, we identify two rhodamine dyes, sulforhodamine B and rhodamine WT, as surface active in albumin solution and investigate whether the dyes lessen ventilation injury. In the isolated rat lung, we micropuncture a surface alveolus, instill albumin solution, and obtain an area with heterogeneous alveolar flooding. We demonstrate that rhodamine dye addition lowers T, reduces ventilation-induced injury, and facilitates liquid escape from flooded alveoli. In vitro we show that rhodamine dye is directly surface active in albumin solution. We identify sulforhodamine B as a potential new therapeutic agent for the treatment of the acute respiratory distress syndrome. PMID:25414246

  6. Sulforhodamine B interacts with albumin to lower surface tension and protect against ventilation injury of flooded alveoli

    PubMed Central

    Kharge, Angana Banerjee; Wu, You

    2014-01-01

    In the acute respiratory distress syndrome, alveolar flooding by proteinaceous edema liquid impairs gas exchange. Mechanical ventilation is used as a supportive therapy. In regions of the edematous lung, alveolar flooding is heterogeneous, and stress is concentrated in aerated alveoli. Ventilation exacerbates stress concentrations and injuriously overexpands aerated alveoli. Injury degree is proportional to surface tension, T. Lowering T directly lessens injury. Furthermore, as heterogeneous flooding causes the stress concentrations, promoting equitable liquid distribution between alveoli should, indirectly, lessen injury. We present a new theoretical analysis suggesting that liquid is trapped in discrete alveoli by a pressure barrier that is proportional to T. Experimentally, we identify two rhodamine dyes, sulforhodamine B and rhodamine WT, as surface active in albumin solution and investigate whether the dyes lessen ventilation injury. In the isolated rat lung, we micropuncture a surface alveolus, instill albumin solution, and obtain an area with heterogeneous alveolar flooding. We demonstrate that rhodamine dye addition lowers T, reduces ventilation-induced injury, and facilitates liquid escape from flooded alveoli. In vitro we show that rhodamine dye is directly surface active in albumin solution. We identify sulforhodamine B as a potential new therapeutic agent for the treatment of the acute respiratory distress syndrome. PMID:25414246

  7. Hexamethylene diisocyanate (HDI) vapor reactivity with glutathione and subsequent transfer to human albumin

    PubMed Central

    Wisnewski, Adam V.; Mhike, Morgen; Hettick, Justin M.; Liu, Jian; Siegel, Paul D.

    2012-01-01

    INTRODUCTION Airway fluid glutathione (GSH) reactivity with inhaled vapors of diisocyanate, a common occupational allergen, is postulated to be a key step in exposure-induced asthma pathogenesis. METHODS A mixed (vapor/liquid) phase exposure system was used to model the in vivo reactivity of inhaled HDI vapor with GSH in the airway fluid. HDI-GSH reaction products, and their capacity to transfer HDI to human albumin, were characterized through mass spectrometry and serologic assays, using HDI-specific polyclonal rabbit serum. RESULTS HDI vapor exposure of 10 mM GSH solutions resulted in primarily S-linked, bis(GSH)-HDI reaction products. In contrast, lower GSH concentrations (100 μM) resulted in mainly mono(GSH)-HDI conjugates, with varying degrees of HDI hydrolysis, dimerization and/or intra-molecular cyclization, depending upon the presence/absence of H2PO4-/HPO42- and Na+/Cl- ions. The ion composition and GSH concentration of the fluid phase, during HDI vapor exposure, strongly influenced the transfer of HDI from GSH to albumin, as did the pH and duration of the carbamoylating reaction. When carbamoylation was performed overnight at pH 7, twenty-five of albumin's lysines were identified as potential sites of conjugation with partially hydrolyzed HDI. When carbamoylation was performed at pH 9, more rapid (within 3 hours) and extensive modification was observed, including additional lysine sites, intra-molecular cross-linkage with HDI, and novel HDI-GSH conjugation. CONCLUSIONS The data define potential mechanisms by which the levels of GSH, H2PO4-4/HPO42-, and/or other ions (e.g. H+/OH-, Na+, Cl-) affect the reactivity of HDI vapor with self-molecules in solution (e.g. airway fluid), and thus, might influence the clinical response to HDI respiratory tract exposure. PMID:23178851

  8. Serum Albumin Levels and Economic Status in Japanese Older Adults

    PubMed Central

    Ota, Asami; Kondo, Naoki; Murayama, Nobuko; Tanabe, Naohito; Shobugawa, Yugo; Kondo, Katsunori

    2016-01-01

    Background Low serum albumin levels are associated with aging and medical conditions such as cancer, liver dysfunction, inflammation, and malnutrition and might be an independent predictor of long-term mortality in healthy older populations. We tested the hypothesis that economic status is associated with serum albumin levels and explained by nutritional and health status in Japanese older adults. Design We performed a cross-sectional analysis using data from the Japan Gerontological Evaluation study (JAGES). The study participants were 6528 functionally independent residents (3189 men and 3339 women) aged ≥65 years living in four municipalities in Aichi prefecture. We used household income as an indicator of economic status. Multiple linear regression was used to compare serum albumin levels in relation to household income, which was classified as low, middle, and high. Additionally, mediation by nutritional and health-related factors was analyzed in multivariable models. Results With the middle-income group as reference, participants with low incomes had a significantly lower serum albumin level, even after adjustment for sex, age, residential area, education, marital status, and household structure. The estimated mean difference was −0.17 g/L (95% confidence interval, −0.33 to −0.01 g/L). The relation between serum albumin level and low income became statistically insignificant when “body mass index”, “consumption of meat or fish”, “self-rated health”, “presence of medical conditions”, “hyperlipidemia”, or “respiratory disease “was included in the model. Conclusion Serum albumin levels were lower in Japanese older adults with low economic status. The decrease in albumin levels appears to be mediated by nutrition and health-related factors with low household incomes. Future studies are needed to reveal the existence of other pathways. PMID:27276092

  9. Albumin Dialysis for Liver Failure: A Systematic Review.

    PubMed

    Tsipotis, Evangelos; Shuja, Asim; Jaber, Bertrand L

    2015-09-01

    Albumin dialysis is the best-studied extracorporeal nonbiologic liver support system as a bridge or destination therapy for patients with liver failure awaiting liver transplantation or recovery of liver function. We performed a systematic review to examine the efficacy and safety of 3 albumin dialysis systems (molecular adsorbent recirculating system [MARS], fractionated plasma separation, adsorption and hemodialysis [Prometheus system], and single-pass albumin dialysis) in randomized trials for supportive treatment of liver failure. PubMed, Ovid, EMBASE, Cochrane's Library, and ClinicalTrials.gov were searched. Two authors independently screened citations and extracted data on patient characteristics, quality of reports, efficacy, and safety end points. Ten trials (7 of MARS and 3 of Prometheus) were identified (620 patients). By meta-analysis, albumin dialysis achieved a net decrease in serum total bilirubin level relative to standard medical therapy of 8.0 mg/dL (95% confidence interval [CI], -10.6 to -5.4) but not in serum ammonia or bile acids. Albumin dialysis achieved an improvement in hepatic encephalopathy relative to standard medical therapy with a risk ratio of 1.55 (95% CI, 1.16-2.08) but had no effect survival with a risk ratio of 0.95 (95% CI, 0.84-1.07). Because of inconsistency in the reporting of adverse events, the safety analysis was limited but did not demonstrate major safety concerns. Use of albumin dialysis as supportive treatment for liver failure is successful at removing albumin-bound molecules, such as bilirubin and at improving hepatic encephalopathy. Additional experience is required to guide its optimal use and address safety concerns. PMID:26311600

  10. Role of single-walled carbon nanotubes on ester hydrolysis and topography of electrospun bovine serum albumin/poly(vinyl alcohol) membranes.

    PubMed

    Ford, Ericka N J; Suthiwangcharoen, Nisaraporn; D'Angelo, Paola A; Nagarajan, Ramanathan

    2014-07-23

    Electrospun membranes were studied for the chemical deactivation of threat agents by means of enzymatic proteins. Protein loading and the surface chemistry of hybrid nanofibers influenced the efficacy by which embedded enzymes could digest the substrate of interest. Bovine serum albumin (BSA), selected as a model protein, was electrospun into biologically active fibers of poly(vinyl alcohol), PVA. Single-walled carbon nanotubes (SWNTs) were blended within these mixtures to promote protein assembly during the process of electrospinning and subsequently the ester hydrolysis of the substrates. The SWNT incorporation was shown to influence the topography of PVA/BSA nanofibers and enzymatic activity against paraoxon, a simulant for organophosphate agents and a phosphorus analogue of p-nitrophenyl acetate (PNA). The esterase activity of BSA against PNA was uncompromised upon its inclusion within nanofibrous membranes because similar amounts of PNA were hydrolyzed by BSA in solution and the electrospun BSA. However, the availability of BSA along the fiber surface was shown to affect the ester hydrolysis of paraoxon. Atomic force microscopy images of nanofibers implicated the surface migration of BSA during the electrospinning of SWNT filled dispersions, especially as greater weight fractions of protein were added to the spinning mixtures. In turn, the PVA/SWNT/BSA nanofibers outperformed the nanotube free PVA/BSA membranes in terms of paraoxon digestion. The results support the development of electrospun polymer nanofiber platforms, modulated by SWNTs for enzyme catalytic applications relevant to soldier protective ensembles. PMID:25007411

  11. In vitro binding of leukotriene B4 (LTB4) to human serum albumin: evidence from spectroscopic, molecular modeling, and competitive displacement studies.

    PubMed

    Zsila, Ferenc; Bikádi, Zsolt; Lockwood, Samuel F

    2005-08-15

    Circular dichroism (CD) and UV absorption spectroscopy were utilized for the first time to investigate the interaction between leukotriene B4 (LTB4) and human serum albumin (HSA) in vitro. The weak intrinsic CD signal of LTB4 was enhanced fivefold in the presence of HSA. The red-shifted, hypochromic, and reduced vibrational fine structure of the ligand/protein UV absorption spectrum indicated complexation of the two molecules in solution. Results obtained from CD titration experiments were subjected to non-linear regression analysis to estimate the binding parameters (Ka = 6.7 x 10(4) M(-1), n = 1). Palmitic acid strongly decreased the induced CD signal of the LTB4/HSA complex, suggesting the role of a high-affinity fatty acid HSA binding site in the leukotriene complexation. Molecular modeling calculations based on the crystal structure of HSA predicted that the long-chain fatty acid site that overlaps with drug binding site II in subdomain IIIA was the most likely binding location for LTB4. Using the drug site II-specific marker ligand rac-ibuprofen, this prediction was confirmed with induced-CD displacement measurements. To the authors' knowledge, the current study represents the first demonstration of binding of LTB4 to HSA in vitro and has implications for the biological transport of this important pro-inflammatory mediator in vivo. PMID:15993588

  12. Uptake and Reactions of Formaldehyde, Acetaldehyde, Acetone, Propanal and Ethanol in Sulfuric Acid solutions at 200-240 K: Implications for upper tropospheric aerosol composition

    NASA Astrophysics Data System (ADS)

    Iraci, L. T.; Williams, M. B.; Axson, J.; Michelsen, R.

    2007-12-01

    The production of light absorbing, organic material in aerosol that is normally considered to be transparent in the UV and visible wavelength regions has significant implications for biogeochemical cycling and climate modelling. Production mechanisms likely involve carbonyl compounds such as formaldehyde, acetone, acetaldehyde and propanal that are present in significant quantities in the upper troposphere (UT). In this study, we have performed experiments focusing on a class of acid catalyzed carbonyl reactions, the formation of acetals. R2C=O + 2R'OH --> R2C(OR')2 + H2O Using a Knudsen cell apparatus, we have measured the rate of uptake of formaldehyde, acetaldehyde, acetone, propanal, and ethanol into sulfuric acid solutions ranging between 40-70 wt% of acid, containing 0-0.1 M of ethanol, acetone or formaldehyde at temperatures of 220-250 K. For all reactant pairs, the aldol condensation path, including self reaction, should be insignificant at the acidities studied. Evidence for reaction between organics was observed for all pairs, except those involving propanal which were likely limited by the very low solubility. We attribute enhanced uptake to the formation of acetals, such as 1,1-diethoxyethane and 2,2- diethoxypropane, among others. Enhanced uptake was observed to proceed on timescales > 1 hour and sometimes shows complex dependence on acidity that is likely related to speciation of the individual carbonyls in acidic solution. The acetal products do not absorb in the visible but are less volatile than parent molecules, allowing for accumulation in sulfuric acid particles, and enhanced uptake. Cross reactions of carbonyls with alcohols in sulfuric acid medium have not been previously measured, yet methanol and ethanol show high solubility and are present at significant concentrations in the UT. Thus even at slow reaction rates, the acetal reaction has ample starting material and proceeds under conditions common to the UT. We will present results for the

  13. Albumin Kinetics in Patients Undergoing Major Abdominal Surgery

    PubMed Central

    Norberg, Åke; Rooyackers, Olav; Segersvärd, Ralf; Wernerman, Jan

    2015-01-01

    Background The drop in plasma albumin concentration following surgical trauma is well known, but the temporal pattern of the detailed mechanisms behind are less well described. The aim of this explorative study was to assess changes in albumin synthesis and transcapillary escape rate (TER) following major surgical trauma, at the time of peak elevations in two well-recognized markers of inflammation. Methods This was a clinical trial of radiolabeled human serum albumin for the study of TER and plasma volume. Ten patients were studied immediately preoperatively and on the 2nd postoperative day after major pancreatic surgery. Albumin synthesis rate was measured by the flooding dose technique employing incorporation of isotopically labelled phenylalanine. Results Fractional synthesis rate of albumin increased from 11.7 (95% CI: 8.9, 14.5) to 15.0 (11.7, 18.4) %/day (p = 0.027), whereas the corresponding absolute synthesis rate was unchanged, 175 (138, 212) versus 150 (107, 192) mg/kg/day (p = 0.21). TER was unchanged, 4.9 (3.1, 6.8) %/hour versus 5.5 (3.9, 7.2) (p = 0.63). Plasma volume was unchanged but plasma albumin decreased from 33.5 (30.9, 36.2) to 22.1 (19.8, 24.3) g/L. (p<0.001). Conclusion Two days after major abdominal surgery, at the time-point when two biomarkers of generalised inflammation were at their peak and the plasma albumin concentration had decreased by 33%, we were unable to show any difference in the absolute synthesis rate of albumin, TER and plasma volume as compared with values obtained immediately pre-operatively. This suggests that capillary leakage, if elevated postoperatively, had ceased at that time-point. The temporal relations between albumin kinetics, capillary leakage and generalised inflammation need to be further explored. Trial Registration clinicaltrialsregister.eu: EudraCT 2010-08529-21 ClinicalTrials.gov NCT01194492 PMID:26313170

  14. Hemoglobin–Albumin Cluster Incorporating a Pt Nanoparticle: Artificial O2 Carrier with Antioxidant Activities

    PubMed Central

    Hosaka, Hitomi; Haruki, Risa; Yamada, Kana; Böttcher, Christoph; Komatsu, Teruyuki

    2014-01-01

    A covalent core–shell structured protein cluster composed of hemoglobin (Hb) at the center and human serum albumins (HSA) at the periphery, Hb-HSAm, is an artificial O2 carrier that can function as a red blood cell substitute. Here we described the preparation of a novel Hb-HSA3 cluster with antioxidant activities and its O2 complex stable in aqueous H2O2 solution. We used an approach of incorporating a Pt nanoparticle (PtNP) into the exterior HSA unit of the cluster. A citrate reduced PtNP (1.8 nm diameter) was bound tightly within the cleft of free HSA with a binding constant (K) of 1.1×107 M−1, generating a stable HSA-PtNP complex. This platinated protein showed high catalytic activities for dismutations of superoxide radical anions (O2•–) and hydrogen peroxide (H2O2), i.e., superoxide dismutase and catalase activities. Also, Hb-HSA3 captured PtNP into the external albumin unit (K = 1.1×107 M−1), yielding an Hb-HSA3(PtNP) cluster. The association of PtNP caused no alteration of the protein surface net charge and O2 binding affinity. The peripheral HSA-PtNP shell prevents oxidation of the core Hb, which enables the formation of an extremely stable O2 complex, even in H2O2 solution. PMID:25310133

  15. Specific albumin binding to microvascular endothelium in culture

    SciTech Connect

    Schnitzer, J.E.; Carley, W.W.; Palade, G.E. )

    1988-03-01

    The specific binding of rat serum albumin (RSA) to confluent microvascular endothelial cells in culture derived from the vasculature of the rat epididymal fat pad was studied at 4{degree}C by radioassay and immunocytochemistry. Radioiodinated RSA ({sup 125}I-RSA) binding to the cells reached equilibrium at {approximately} 20 min incubation. Albumin binding was a slowly saturating function over concentrations ranging from 0.01 to 50 mg/ml. Specific RSA binding with a moderate apparent affinity constant of 1.0 mg/ml and with a maximum binding concentration of 90 ng/cm{sup 2} was immunolocalized with anti-RSA antibody to the outer (free) side of the enothelium. Scatchard analysis of the binding yielded a nonlinear binding curve with a concave-upward shape. Dissociation rate analysis supports negative cooperativity of albumin binding, but multiple binding sites may also be present. Albumin binding fulfilled many requirements for ligand specificity including saturability, reversibility, competibility, and dependence on both cell type and cell number. The results are discussed in terms of past in situ investigations on the localization of albumin binding to vascular endothelium and its effect on transendothelial molecular transport.

  16. Albumin-based nanocomposite spheres for advanced drug delivery systems.

    PubMed

    Misak, Heath E; Asmatulu, Ramazan; Gopu, Janani S; Man, Ka-Poh; Zacharias, Nora M; Wooley, Paul H; Yang, Shang-You

    2014-01-01

    A novel drug delivery system incorporating human serum albumin, poly(lactic-co-glycolic acid, magnetite nanoparticles, and therapeutic agent(s) was developed for potential application in the treatment of diseases such as rheumatoid arthritis and skin cancer. An oil-in-oil emulsion/solvent evaporation (O/OSE) method was modified to produce a drug delivery system with a diameter of 0.5–2 μm. The diameter was mainly controlled by adjusting the viscosity of albumin in the discontinuous phase of the O/OSE method. The drug-release study showed that the release of drug and albumin was mostly dependent on the albumin content of the drug delivery system, which is very similar to the drug occlusion-mesopore model. Cytotoxicity tests indicated that increasing the albumin content in the drug delivery system increased cell viability, possibly due to the improved biocompatibility of the system. Overall, these studies show that the proposed system could be a viable option as a drug delivery system in the treatment of many illnesses, such as rheumatoid arthritis, and skin and breast cancers. PMID:24106002

  17. Regional differences in pleural lymphatic albumin concentration in sheep

    SciTech Connect

    Albertine, K.H.; Schultz, E.L.; Wiener-Kronish, J.P.; Staub, N.C.

    1987-01-01

    We used quantitative reflectance autoradiography to compare the concentration of albumin in visceral pleural lymphatics at the cranial and caudal ends of the sheep's lung in the vertical (60 degrees head-up) and horizontal (supine) positions. Twelve to fourteen hours after injecting 125I-albumin intravenously we placed four anesthetized sheep in the vertical position to establish a microvascular hydrostatic pressure gradient along the vertical height of the lung. We placed two anesthetized sheep in the horizontal position. Four hours later, we fixed the left lung and removed visceral pleural tissue blocks from the cranial and caudal ends, separated by a 15-cm distance, along the costovertebral margin. We measured the silver grain density in the pleural lymphatic autoradiograms by dark-field reflectance microspectrophotometry. In the vertical position, the lymph albumin concentration at the cranial end (top) of the lung averaged 2.5 +/- 0.4 g/dl compared with the caudal end (bottom), which averaged 1.8 +/- 0.3 g/dl. The difference (42% greater at the top than the bottom) is significant (P less than 0.05). The computed gradient in perimicrovascular interstitial albumin osmotic pressure was 0.26 +/- 0.13 cmH2O/cm lung height. There were no differences between the cranial and caudal lymphatic groups in the two horizontal sheep. We conclude that in the sheep lung there is a gradient in perimicrovascular albumin concentration due to the vertical gradient in microvascular hydrostatic pressure.

  18. A Homogeneous Fluorescent Sensor for Human Serum Albumin

    PubMed Central

    Wang, Rongsheng E.; Tian, Ling; Chang, Yie-Hwa

    2012-01-01

    Human serum albumin is the most abundant protein in the body and is an important biomarker used for disease-related diagnosis. Although the traditional enzyme-linked immunosorbent assay (ELISA) approach can precisely measure the concentration of human serum albumin, the multi-step procedure and time-consuming preparations of ELISA limit its diagnostic applications, preventing accurate point-of-care testing, for example. Herein, we report the recent development of an antibody-based albumin sensor that allows for a homogeneous measurement of albumin concentrations in saliva, urine and serum, in which this type of sensor is validated for the first time. The assay only requires simple mixing, and relies on time-resolved (TR) fluorescence resonance energy transfer (FRET) to produce robust, sensitive signals. The whole process, from sample preparation to final read-out, is expected to take less than one hour and requires only a standard plate-reader, thus making the sensor a convenient and cost-effective tool for albumin analysis. PMID:22326845

  19. Albumin microvascular leakage in brains with diabetes mellitus.

    PubMed

    Fujihara, Ryuji; Chiba, Yoichi; Nakagawa, Toshitaka; Nishi, Nozomu; Murakami, Ryuta; Matsumoto, Koichi; Kawauchi, Machi; Yamamoto, Tetsuji; Ueno, Masaki

    2016-09-01

    Their aim was to examine whether microvascular leakage of endogenous albumin, a representative marker for blood-brain barrier (BBB) damage, was induced in the periventricular area of diabetic db/db mice because periventricular white matter hyperintensity formation in magnetic resonance images was accelerating in elderly patients with diabetes mellitus. Using light and electron microscopes, and semi-quantitative analysis techniques, immunoreactivity of endogenous albumin, indicating vascular permeability, was examined in the periventricular area and spinal cord of db/db mice and db/+m control mice. Greater immunoreactivity of albumin was observed in the vessel wall of the periventricular area of db/db mice than in controls. Additionally, weak immunoreactivity was observed in the spinal cord of both db/db mice and controls. The number of gold particles, indicating immunoreactivity of albumin, in the perivascular area of db/db mice was significantly higher than that of control mice, but there was no significant difference in the number of particles in the spinal cord between db/db mice and controls. These findings suggest that albumin microvascular leakage, or BBB breakdown, is induced in the periventricular area of diabetic mice. Microsc. Res. Tech. 79:833-837, 2016. © 2016 Wiley Periodicals, Inc. PMID:27333535

  20. Paramagnetic perfluorocarbon-filled albumin-(Gd-DTPA) microbubbles for the induction of focused-ultrasound-induced blood-brain barrier opening and concurrent MR and ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Liao, Ai-Ho; Liu, Hao-Li; Su, Chia-Hao; Hua, Mu-Yi; Yang, Hung-Wei; Weng, Yu-Ting; Hsu, Po-Hung; Huang, Sheng-Min; Wu, Shih-Yen; Wang, Hsin-Ell; Yen, Tzu-Chen; Li, Pai-Chi

    2012-05-01

    This paper presents new albumin-shelled Gd-DTPA microbubbles (MBs) that can concurrently serve as a dual-modality contrast agent for ultrasound (US) imaging and magnetic resonance (MR) imaging to assist blood-brain barrier (BBB) opening and detect intracerebral hemorrhage (ICH) during focused ultrasound brain drug delivery. Perfluorocarbon-filled albumin-(Gd-DTPA) MBs were prepared with a mean diameter of 2320 nm and concentration of 2.903×109 MBs ml-1 using albumin-(Gd-DTPA) and by sonication with perfluorocarbon (C3F8) gas. The albumin-(Gd-DTPA) MBs were then centrifuged and the procedure was repeated until the free Gd3+ ions were eliminated (which were detected by the xylenol orange sodium salt solution). The albumin-(Gd-DTPA) MBs were also characterized and evaluated both in vitro and in vivo by US and MR imaging. Focused US was used with the albumin-(Gd-DTPA) MBs to induce disruption of the BBB in 18 rats. BBB disruption was confirmed with contrast-enhanced T1-weighted turbo-spin-echo sequence MR imaging. Heavy T2*-weighted 3D fast low-angle shot sequence MR imaging was used to detect ICH. In vitro US imaging experiments showed that albumin-(Gd-DTPA) MBs can significantly enhance the US contrast in T1-, T2- and T2*-weighted MR images. The r1 and r2 relaxivities for Gd-DTPA were 7.69 and 21.35 s-1mM-1, respectively, indicating that the MBs represent a positive contrast agent in T1-weighted images. In vivo MR imaging experiments on 18 rats showed that focused US combined with albumin-(Gd-DTPA) MBs can be used to both induce disruption of the BBB and detect ICH. To compare the signal intensity change between pure BBB opening and BBB opening accompanying ICH, albumin-(Gd-DTPA) MB imaging can provide a ratio of 5.14 with significant difference (p = 0.026), whereas Gd-DTPA imaging only provides a ratio of 2.13 and without significant difference (p = 0.108). The results indicate that albumin-(Gd-DTPA) MBs have potential as a US/MR dual-modality contrast agent for

  1. Acute hypoproteinemic fluid overload: its determinants, distribution, and treatment with concentrated albumin and diuretics.

    PubMed

    Pappova, E; Bachmeier, W; Crevoisier, J L; Kollar, J; Kollar, M; Tobler, P; Zahler, H W; Zaugg, D; Lundsgaard-Hansen, P

    1977-01-01

    We simulated the use of massive volumes of crystalloid fluids as a treatment of acute plasma loss in a standardized experimental model and studied the factors determining the retention or excretion of the resulting acute hypoproteinemic fluid overload, its distribution within the body, and its treatment with concentrated albumin and diuretics. In accordance with the classic Starling concept, the serum protein level, i.e. the serum colloid osmotic pressure, determined the excretion/retention ratio of a given water and sodium load. Of the total fluid retention, fat and muscle each accommodated 25%, whereas the skin, which contributes only 7% to the total body weight, accounted for 37% and increased its volume by roughly one third. Concentrated albumin promoted fluid excretion in direct proportion to the achieved increment of the serum protein level and abolished the edema of fat, muscle and skin. Furosemide was virtually ineffective. The implications of these results for the 'adult respiratory distress syndrome' and disturbed wound healing are discussed and related to the concept of a critical threshold of the serum protein level. PMID:919420

  2. Scaffold materials from glycosylated and PEGylated bovine serum albumin.

    PubMed

    Wang, Kai; David, Allan E; Choi, Young-Suk; Wu, Yonnie; Buschle-Diller, Gisela

    2015-09-01

    Bovine serum albumin has been PEGylated and glycosylated to create mimetic materials for the extracellular matrix (ECM) with potential tissue engineering applications. Different surfaces for cell adhesion were achieved by crosslinking the initial albumin product and forming either a coating or a sponge-like three-dimensional morphology to mimic the mesh structure of natural ECM. The biocompatibility of the albumin matrix with mammalian cells was evaluated using cell culture assays with NIH 3T3 cells. The results indicated that glycoprotein composition and specific morphology of the assembly can improve the cell growth environment. These ECM mimetic structures might eventually be considered to serve as alternatives for the more expensive collagen and elastin based ECM substances currently in use in tissue engineering. PMID:25691091

  3. Unraveling the Interaction between FcRn and Albumin: Opportunities for Design of Albumin-Based Therapeutics

    PubMed Central

    Sand, Kine Marita Knudsen; Bern, Malin; Nilsen, Jeannette; Noordzij, Hanna Theodora; Sandlie, Inger; Andersen, Jan Terje

    2015-01-01

    The neonatal Fc receptor (FcRn) was first found to be responsible for transporting antibodies of the immunoglobulin G (IgG) class from the mother to the fetus or neonate as well as for protecting IgG from intracellular catabolism. However, it has now become apparent that the same receptor also binds albumin and plays a fundamental role in homeostatic regulation of both IgG and albumin, as FcRn is expressed in many different cell types and organs at diverse body sites. Thus, to gain a complete understanding of the biological function of each ligand, and also their distribution in the body, an in-depth characterization of how FcRn binds and regulates the transport of both ligands is necessary. Importantly, such knowledge is also relevant when developing new drugs, as IgG and albumin are increasingly utilized in therapy. This review discusses our current structural and biological understanding of the relationship between FcRn and its ligands, with a particular focus on albumin and design of albumin-based therapeutics. PMID:25674083

  4. PEGylated Albumin-Based Polyion Complex Micelles for Protein Delivery.

    PubMed

    Jiang, Yanyan; Lu, Hongxu; Chen, Fan; Callari, Manuela; Pourgholami, Mohammad; Morris, David L; Stenzel, Martina H

    2016-03-14

    An increasing amount of therapeutic agents are based on proteins. However, proteins as drug have intrinsic problems such as their low hydrolytic stability. Delivery of proteins using nanoparticles has increasingly been the focus of interest with polyion complex micelles, prepared from charged block copolymer and the oppositely charged protein, as an example of an attractive carrier for proteins. Inspired by this approach, a more biocompatible pathway has been developed here, which replaces the charged synthetic polymer with an abundant protein, such as albumin. Although bovine serum albumin (BSA) was observed to form complexes with positively charged proteins directly, the resulting protein nanoparticle were not stable and aggregated to large precipitates over the course of a day. Therefore, maleimide functionalized poly(oligo (ethylene glycol) methyl ether methacrylate) (MI-POEGMEMA) (Mn = 26000 g/mol) was synthesized to generate a polymer-albumin conjugate, which was able to condense positively charged proteins, here lysozyme (Lyz) as a model. The PEGylated albumin polyion complex micelle with lysozyme led to nanoparticles between 15 and 25 nm in size depending on the BSA to Lyz ratio. The activity of the encapsulated protein was tested using Sprouty 1 (C-12; Spry1) proteins, which can act as an endogenous angiogenesis inhibitor. Condensation of Spry1 with the PEGylated albumin could improve the anticancer efficacy of Spry1 against the breast cancer cells lowering the IC50 value of the protein. Furthermore, the high anticancer efficacy of the POEGMEMA-BSA/Spry1 complex micelle was verified by effectively inhibiting the growth of three-dimensional MCF-7 multicellular tumor spheroids. The PEGylated albumin complex micelle has great potential as a drug delivery vehicle for a new generation of cancer pharmaceuticals. PMID:26809948

  5. Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis

    PubMed Central

    2016-01-01

    Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients. PMID:26955238

  6. Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis.

    PubMed

    Pieringer, Herwig; Brummaier, Tobias; Piringer, Bettina; Auer-Hackenberg, Lorenz; Hartl, Andreas; Puchner, Rudolf; Pohanka, Erich; Schmid, Michael

    2016-03-01

    Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients. PMID:26955238

  7. Statin-sensitive endocytosis of albumin by glomerular podocytes.

    PubMed

    Eyre, Jeanette; Ioannou, Kyriakos; Grubb, Blair D; Saleem, Moin A; Mathieson, Peter W; Brunskill, Nigel J; Christensen, Erik I; Topham, Peter S

    2007-02-01

    Glomerular podocytes are critical regulators of glomerular permeability via the slit diaphragm and may play a role in cleaning the glomerular filter. Whether podocytes are able to endocytose proteins is uncertain. We studied protein endocytosis in conditionally immortalized mouse and human podocytes using FITC-albumin by direct quantitative assay and by fluorescence microscopy and electron microscopy in mouse podocytes. Furthermore, in vivo uptake was studied in human, rat, and mouse podocytes. Both mouse and human podocytes displayed specific one-site binding for FITC-albumin with K(d) of 0.91 or 0.44 mg/ml and B(max) of 3.15 or 0.81 microg/mg cell protein, respectively. In addition, they showed avid endocytosis of FITC-albumin with K(m) of 9.48 or 4.5 mg/ml and V(max) of 474.3 or 97.4 microg.mg cell protein(-1).h(-1), respectively. Immunoglobulin and transferrin were inefficient competitors of this process, indicating some specificity for albumin. Accumulation of endocytosed albumin could be demonstrated in intracellular vesicles by fluorescence confocal microscopy and electron microscopy. Endocytosis was sensitive to pretreatment with simvastatin. In vivo accumulation of albumin was found in all three species but was most pronounced in the rat. We conclude that podocytes are able to endocytose protein in a statin-sensitive manner. This function is likely to be highly significant in health and disease. In addition, protein endocytosis by podocytes may represent a useful, measurable phenotypic characteristic against which potentially injurious or beneficial interventions can be assessed. PMID:17032937

  8. Interaction of lipid vesicle with silver nanoparticle-serum albumin protein corona

    PubMed Central

    Chen, Ran; Choudhary, Poonam; Schurr, Ryan N.; Bhattacharya, Priyanka; Brown, Jared M.; Chun Ke, Pu

    2012-01-01

    The physical interaction between a lipid vesicle and a silver nanoparticle (AgNP)-human serum albumin (HSA) protein “corona” has been examined. Specifically, the binding of AgNPs and HSA was analyzed by spectrophotometry, and the induced conformational changes of the HSA were inferred from circular dichroism spectroscopy. The fluidity of the vesicle, a model system for mimicking cell membrane, was found to increase with the increased exposure to AgNP-HSA corona, though less pronounced compared to that induced by AgNPs alone. This study offers additional information for understanding the role of physical forces in nanoparticle-cell interaction and has implications for nanomedicine and nanotoxicology. PMID:22271932

  9. Size-dependent denaturing kinetics of bovine serum albumin adsorbed onto gold nanospheres

    NASA Astrophysics Data System (ADS)

    Teichroeb, J. H.; Forrest, J. A.; Jones, L. W.

    2008-08-01

    We have used localized surface plasmon resonance (LSPR) to monitor the kinetics of thermal denaturing of bovine serum albumin (BSA) adsorbed onto gold nanospheres of size 5nm-100nm. The effect of the protein on the LSPR was monitored by visible extinction spectroscopy. The wavelength of the peak extinction (resonance) is affected by the conformation of the adsorbed protein layer, and as such can be used as a very sensitive probe of thermal denaturing that is specific to the adsorbed (as opposed to free) protein. The time dependence of the denaturing is measured in the temperature range 60 °C - 70 °C , and the lifetimes are used to calculate an activation barrier for thermal denaturing. The results show that thermally activated denaturing of proteins adsorbed onto nanoparticles has a nanoparticle-size-dependent activation barrier, and this barrier increases for decreasing particle size. This may have important implications for other protein-nanoparticle interactions.

  10. In vivo uptake of heterologous alphafetoprotein and serum albumin by ependymal cells of developing chick embryos.

    PubMed

    Moro, R; Fielitz, W; Esteves, A; Grunberg, J; Uriel, J

    1984-01-01

    The in vivo uptake by neuroepithelial cells of rat serum proteins injected into the mesencephalic cavity of developing chicken was demonstrated by immunohistochemical methods. It was found that 48 h after inoculation, rat alphafetoprotein (AFP) and serum albumin (SA) localize in the same places as do chicken AFP and SA. No labelling was present for rat or chicken IgG. We also present evidence showing that chicken ovalbumin, which is not normally found inside ependymal cells is not internalized even when injected into the cerebrospinal fluid at 30-fold its physiological concentration. The existence of transient specific receptors which could be responsible for this protein uptake is proposed. The possible implications in relation to developmental biology are discussed. PMID:24873957

  11. Neuronal uptake of serum albumin is associated with neuron damage during the development of epilepsy

    PubMed Central

    Liu, Zanhua; Liu, Jinjie; Wang, Suping; Liu, Sibo; Zhao, Yongbo

    2016-01-01

    It is well established that brain blood barrier dysfunction following the onset of seizures may lead to serum albumin extravasation into the brain. However, the effect of albumin extravasation on the development of epilepsy is yet to be fully elucidated. Previous studies have predominantly focused on the effect of albumin absorption by astrocytes; however, the present study investigated the effects of neuronal uptake of albumin in vitro and in kainic acid-induced Sprague-Dawley rat models of temporal lobe epilepsy. In the present study, electroencephalogram recordings were conducted to record seizure onset, Nissl and Evans blue staining were used to detect neuronal damage and albumin extravasation, respectively, and double immunofluorescence was used to explore neuronal absorption of albumin. Cell counting was also conducted in vitro to determine whether albumin contributes to neuronal death. The results of the present study indicated that extravasated serum albumin was absorbed by neurons, and the neurons that had absorbed albumin died and were dissolved 28 days after seizure onset in vivo. Furthermore, significant neuronal death was detected after albumin absorption in vitro in a dose- and time-dependent manner. These results suggested that albumin may be absorbed by neurons following the onset of seizures. Furthermore, the results indicated that neuronal albumin uptake may be associated with neuronal damage and death in epileptic seizures. Therefore, attenuating albumin extravasation following epileptic seizures may reduce brain damage and slow the development of epilepsy. PMID:27446263

  12. Mechanism of increased clearance of glycated albumin by proximal tubule cells.

    PubMed

    Wagner, Mark C; Myslinski, Jered; Pratap, Shiv; Flores, Brittany; Rhodes, George; Campos-Bilderback, Silvia B; Sandoval, Ruben M; Kumar, Sudhanshu; Patel, Monika; Ashish; Molitoris, Bruce A

    2016-05-01

    Serum albumin is the most abundant plasma protein and has a long half-life due to neonatal Fc receptor (FcRn)-mediated transcytosis by many cell types, including proximal tubule cells of the kidney. Albumin also interacts with, and is modified by, many small and large molecules. Therefore, the focus of the present study was to address the impact of specific known biological albumin modifications on albumin-FcRn binding and cellular handling. Binding at pH 6.0 and 7.4 was performed since FcRn binds albumin strongly at acidic pH and releases it after transcytosis at physiological pH. Equilibrium dissociation constants were measured using microscale thermophoresis. Since studies have shown that glycated albumin is excreted in the urine at a higher rate than unmodified albumin, we studied glucose and methylgloxal modified albumins (21 days). All had reduced affinity to FcRn at pH 6.0, suggesting these albumins would not be returned to the circulation via the transcytotic pathway. To address why modified albumin has reduced affinity, we analyzed the structure of the modified albumins using small-angle X-ray scattering. This analysis showed significant structural changes occurring to albumin with glycation, particularly in the FcRn-binding region, which could explain the reduced affinity to FcRn. These results offer an explanation for enhanced proximal tubule-mediated sorting and clearance of abnormal albumins. PMID:26887834

  13. Chromatographic removal and heat inactivation of hepatitis A virus during manufacture of human albumin.

    PubMed

    Adcock, W L; MacGregor, A; Davies, J R; Hattarki, M; Anderson, D A; Goss, N H

    1998-08-01

    CSL Limited, an Australian biopharmaceutical company, has recently converted its method of manufacture for human albumin from a traditional Cohn-ethanol fractionation method to a method employing chromatographic techniques. Studies were undertaken to determine the efficiency of the chromatographic and pasteurization steps used in the manufacture of Albumex(R) (CSL's trade name for albumin) in removing and inactivating the potential viral contaminant, hepatitis A virus (HAV). The manufacturing process for Albumex(R) includes three chromatographic steps, two of which are ion-exchange steps (DEAE-Sepharose(R) Fast Flow and CM-Sepharose(R) Fast Flow) and the third is a gel-filtration step (Sephacryl(R) S200 HR). The final stage of the Albumex(R) process involves a bulk pasteurization step where product is held at 60 degrees C for 10 h. HAV partitioning experiments on the DEAE-Sepharose(R) FF and CM-Sepharose(R) FF ion-exchange and Sephacryl(R) S200 HR gel-filtration columns were performed with scaled-down models of the production-scale chromatographic Albumex(R) process. Production samples collected before each of the chromatographic steps were spiked with HAV and processed through each of the scaled-down chromatographic columns. Samples collected during processing were assayed and the log10 reduction factors calculated. Inactivation kinetics of HAV were examined during the pasteurization of Albumex(R) 5 and 20 [5% and 20% (w/v) albumin solutions] held at 60 degrees C for 10 h. Log10 reductions for HAV through the DEAE-Sepharose(R) FF, CM-Sepharose(R) FF and Sephacryl(R) S200 HR chromatographic columns were 5.3, 1.5 and 4.2 respectively, whereas a 4.4 and a greater than 3.9 log10 reduction in HAV in Albumex(R) 5 and 20 respectively were achieved during pasteurization. PMID:9693093

  14. Comparison of hetastarch to albumin for perioperative bleeding in patients undergoing abdominal aortic aneurysm surgery. A prospective, randomized study.

    PubMed Central

    Gold, M S; Russo, J; Tissot, M; Weinhouse, G; Riles, T

    1990-01-01

    The effects of hetastarch and human albumin solutions on perioperative bleeding and coagulation parameters during abdominal aortic aneurysm repair were compared. In two randomized groups of 20 patients, albumin 5% (group 1) or hetastarch 6% (group 2) 1 g/kg was given during surgery. The remaining perioperative fluids consisted of lactated ringers and packed red blood cells. Perioperative coagulation measurements included partial thromboplastin time, prothrombin time, activated clotting time, platelet count, and bleeding time. Estimated blood loss and the total amount of crystalloid and blood infused were also measured. The surgeon, blind to the colloid used, subjectively rated bleeding on a scale of 1 to 10. There was no significant difference between groups for any measured parameter at any time. Measurements of coagulation function were within normal limits for both groups. Hetastarch does not cause clotting disorders in patients undergoing abdominal aortic aneurysm repair, at least if the quantities used in this study are not exceeded. PMID:1690974

  15. Viscoelastic behavior and microstructure of protein solutions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty percent solutions of calcium caseinate (CC), egg albumin (EA), fish protein isolate (FPI), soy protein isolate (SPI), wheat gluten (WG), and whey protein isolate (WPI) were examined during heating by small amplitude oscillatory shear measurements, which provided an indication of protein behav...

  16. Effect of baseline serum albumin concentration on outcome of resuscitation with albumin or saline in patients in intensive care units: analysis of data from the saline versus albumin fluid evaluation (SAFE) study

    PubMed Central

    Study Investigators, SAFE

    2006-01-01

    Objective To determine whether outcomes of resuscitation with albumin or saline in the intensive care unit depend on patients' baseline serum albumin concentration. Design Analysis of data from a double blind, randomised controlled trial. Setting Intensive care units of 16 hospitals in Australia and New Zealand. Participants 6045 participants in the saline versus albumin fluid evaluation (SAFE) study. Interventions Fluid resuscitation with 4% albumin or saline in patients with a baseline serum albumin concentration of 25 g/l or less or more than 25 g/l. Main outcome measures Primary outcome was all cause mortality at 28 days. Secondary outcomes were length of stay in the intensive care unit, length of stay in hospital, duration of renal replacement therapy, and duration of mechanical ventilation. Main results The odds ratios for death for albumin compared with saline for patients with a baseline serum albumin concentration of 25 g/l or less and more than 25 g/l were 0.87 and 1.09, respectively (ratio of odds ratios 0.80, 95% confidence interval 0.63 to 1.02); P=0.08 for heterogeneity. No significant interaction was found between baseline serum albumin concentration as a continuous variable and the effect of albumin and saline on mortality. No consistent interaction was found between baseline serum albumin concentration and treatment effects on length of stay in the intensive care unit, length of hospital stay, duration of renal replacement therapy, or duration of mechanical ventilation. Conclusion The outcomes of resuscitation with albumin and saline are similar irrespective of patients' baseline serum albumin concentration. Trial registration ISRCTN76588266. PMID:17040925

  17. Implications of preoperative hypoalbuminemia in colorectal surgery.

    PubMed

    Truong, Adam; Hanna, Mark H; Moghadamyeghaneh, Zhobin; Stamos, Michael J

    2016-05-27

    Serum albumin has traditionally been used as a quantitative measure of a patient's nutritional status because of its availability and low cost. While malnutrition has a clear definition within both the American and European Societies for Parenteral and Enteral Nutrition clinical guidelines, individual surgeons often determine nutritional status anecdotally. Preoperative albumin level has been shown to be the best predictor of mortality after colorectal cancer surgery. Specifically in colorectal surgical patients, hypoalbuminemia significantly increases the length of hospital stay, rates of surgical site infections, enterocutaneous fistula risk, and deep vein thrombosis formation. The delay of surgical procedures to allow for preoperative correction of albumin levels in hypoalbuminemic patients has been shown to improve the morbidity and mortality in patients with severe nutritional risk. The importance of preoperative albumin levels and the patient's chronic inflammatory state on the postoperative morbidity and mortality has led to the development of a variety of surgical scoring systems to predict outcomes efficiently. This review attempts to provide a systematic overview of albumin and its role and implications in colorectal surgery. PMID:27231513

  18. Implications of preoperative hypoalbuminemia in colorectal surgery

    PubMed Central

    Truong, Adam; Hanna, Mark H; Moghadamyeghaneh, Zhobin; Stamos, Michael J

    2016-01-01

    Serum albumin has traditionally been used as a quantitative measure of a patient’s nutritional status because of its availability and low cost. While malnutrition has a clear definition within both the American and European Societies for Parenteral and Enteral Nutrition clinical guidelines, individual surgeons often determine nutritional status anecdotally. Preoperative albumin level has been shown to be the best predictor of mortality after colorectal cancer surgery. Specifically in colorectal surgical patients, hypoalbuminemia significantly increases the length of hospital stay, rates of surgical site infections, enterocutaneous fistula risk, and deep vein thrombosis formation. The delay of surgical procedures to allow for preoperative correction of albumin levels in hypoalbuminemic patients has been shown to improve the morbidity and mortality in patients with severe nutritional risk. The importance of preoperative albumin levels and the patient’s chronic inflammatory state on the postoperative morbidity and mortality has led to the development of a variety of surgical scoring systems to predict outcomes efficiently. This review attempts to provide a systematic overview of albumin and its role and implications in colorectal surgery. PMID:27231513

  19. Human serum albumin homeostasis: a new look at the roles of synthesis, catabolism, renal and gastrointestinal excretion, and the clinical value of serum albumin measurements.

    PubMed

    Levitt, David G; Levitt, Michael D

    2016-01-01

    Serum albumin concentration (CP) is a remarkably strong prognostic indicator of morbidity and mortality in both sick and seemingly healthy subjects. Surprisingly, the specifics of the pathophysiology underlying the relationship between CP and ill-health are poorly understood. This review provides a summary that is not previously available in the literature, concerning how synthesis, catabolism, and renal and gastrointestinal clearance of albumin interact to bring about albumin homeostasis, with a focus on the clinical factors that influence this homeostasis. In normal humans, the albumin turnover time of about 25 days reflects a liver albumin synthesis rate of about 10.5 g/day balanced by renal (≈6%), gastrointestinal (≈10%), and catabolic (≈84%) clearances. The acute development of hypoalbuminemia with sepsis or trauma results from increased albumin capillary permeability leading to redistribution of albumin from the vascular to interstitial space. The best understood mechanism of chronic hypoalbuminemia is the decreased albumin synthesis observed in liver disease. Decreased albumin production also accounts for hypoalbuminemia observed with a low-protein and normal caloric diet. However, a calorie- and protein-deficient diet does not reduce albumin synthesis and is not associated with hypoalbuminemia, and CP is not a useful marker of malnutrition. In most disease states other than liver disease, albumin synthesis is normal or increased, and hypoalbuminemia reflects an enhanced rate of albumin turnover resulting either from an increased rate of catabolism (a poorly understood phenomenon) or enhanced loss of albumin into the urine (nephrosis) or intestine (protein-losing enteropathy). The latter may occur with subtle intestinal pathology and hence may be more prevalent than commonly appreciated. Clinically, reduced CP appears to be a result rather than a cause of ill-health, and therapy designed to increase CP has limited benefit. The ubiquitous occurrence of

  20. Human serum albumin homeostasis: a new look at the roles of synthesis, catabolism, renal and gastrointestinal excretion, and the clinical value of serum albumin measurements

    PubMed Central

    Levitt, David G; Levitt, Michael D

    2016-01-01

    Serum albumin concentration (CP) is a remarkably strong prognostic indicator of morbidity and mortality in both sick and seemingly healthy subjects. Surprisingly, the specifics of the pathophysiology underlying the relationship between CP and ill-health are poorly understood. This review provides a summary that is not previously available in the literature, concerning how synthesis, catabolism, and renal and gastrointestinal clearance of albumin interact to bring about albumin homeostasis, with a focus on the clinical factors that influence this homeostasis. In normal humans, the albumin turnover time of about 25 days reflects a liver albumin synthesis rate of about 10.5 g/day balanced by renal (≈6%), gastrointestinal (≈10%), and catabolic (≈84%) clearances. The acute development of hypoalbuminemia with sepsis or trauma results from increased albumin capillary permeability leading to redistribution of albumin from the vascular to interstitial space. The best understood mechanism of chronic hypoalbuminemia is the decreased albumin synthesis observed in liver disease. Decreased albumin production also accounts for hypoalbuminemia observed with a low-protein and normal caloric diet. However, a calorie- and protein-deficient diet does not reduce albumin synthesis and is not associated with hypoalbuminemia, and CP is not a useful marker of malnutrition. In most disease states other than liver disease, albumin synthesis is normal or increased, and hypoalbuminemia reflects an enhanced rate of albumin turnover resulting either from an increased rate of catabolism (a poorly understood phenomenon) or enhanced loss of albumin into the urine (nephrosis) or intestine (protein-losing enteropathy). The latter may occur with subtle intestinal pathology and hence may be more prevalent than commonly appreciated. Clinically, reduced CP appears to be a result rather than a cause of ill-health, and therapy designed to increase CP has limited benefit. The ubiquitous occurrence of

  1. Impact of albumin on drug delivery--new applications on the horizon.

    PubMed

    Elsadek, Bakheet; Kratz, Felix

    2012-01-10

    Over the past decades, albumin has emerged as a versatile carrier for therapeutic and diagnostic agents, primarily for diagnosing and treating diabetes, cancer, rheumatoid arthritis and infectious diseases. Market approved products include fatty acid derivatives of human insulin or the glucagon-like-1 peptide (Levemir(®) and Victoza(®)) for treating diabetes, the taxol albumin nanoparticle Abraxane(®) for treating metastatic breast cancer which is also under clinical investigation in further tumor indications, and (99m)Tc-aggregated albumin (Nanocoll(®) and Albures(®)) for diagnosing cancer and rheumatoid arthritis as well as for lymphoscintigraphy. In addition, an increasing number of albumin-based or albumin-binding drugs are in clinical trials such as antibody fusion proteins (MM-111) for treating HER2/neu positive breast cancer (phase I), a camelid albumin-binding nanobody anti-HSA-anti-TNF-α (ATN-103) in phase II studies for treating rheumatoid arthritis, an antidiabetic Exendin-4 analog bound to recombinant human albumin (phase I/II), a fluorescein-labeled albumin conjugate (AFL)-human serum albumin for visualizing the malignant borders of brain tumors for improved surgical resection, and finally an albumin-binding prodrug of doxorubicin (INNO-206) entering phase II studies against sarcoma and gastric cancer. In the preclinical setting, novel approaches include attaching peptides with high-affinity for albumin to antibody fragments, the exploitation of albumin-binding gadolinium contrast agents for magnetic resonance imaging, and physical or covalent attachment of antiviral, antibacterial, and anticancer drugs to albumin that are permanently or transiently attached to human serum albumin (HSA) or act as albumin-binding prodrugs. This review gives an overview of the expanding field of preclinical and clinical drug applications and developments that use albumin as a protein carrier to improve the pharmacokinetic profile of the drug or to target the drug

  2. Protein extracts from cultured cells contain nonspecific serum albumin.

    PubMed

    Miyara, Masatsugu; Umeda, Kanae; Ishida, Keishi; Sanoh, Seigo; Kotake, Yaichiro; Ohta, Shigeru

    2016-06-01

    Serum is an important component of cell culture media. The present study demonstrates contamination of intracellular protein extract by bovine serum albumin from the culture media and illustrates how this contamination can cause the misinterpretation of western blot results. Preliminary experiments can prevent the misinterpretation of some experimental results, and optimization of the washing process may enable specific protein detection. PMID:26967711

  3. Albumin induced cytokine expression in porcine adipose tissue explants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Albumin has historically been included in medium designed for use with adipose tissue when evaluating metabolism, gene expression or protein secretion. However, recent studies with mouse adipocytes (Ruan et al., J. Biol. Chem. 278:47585-47593, 2003) and human adipose tissue (Schlesinger et al., Ame...

  4. 21 CFR 862.1035 - Albumin test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Albumin test system. 862.1035 Section 862.1035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  5. 21 CFR 862.1035 - Albumin test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Albumin test system. 862.1035 Section 862.1035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  6. 21 CFR 862.1035 - Albumin test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Albumin test system. 862.1035 Section 862.1035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  7. 21 CFR 862.1035 - Albumin test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Albumin test system. 862.1035 Section 862.1035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  8. 21 CFR 862.1035 - Albumin test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Albumin test system. 862.1035 Section 862.1035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  9. Interaction of purine bases and nucleosides with serum albumin

    NASA Astrophysics Data System (ADS)

    Sułkowska, A.; Michnik, A.

    1997-06-01

    The proton NMR spectra of alkyl derivatives of adenine and adenosine have been studied. High-resolution (400 MHz) proton spectra were recorded at 300 K at increasing concentrations of serum albumin. The dependence of the chemical shifts and the line width of the individual spectral lines on the protein concentration provides some detailed information about the nature of the complexes between the purine derivatives and albumin. Comparison of data for the methylated and non-methylated purine bases and nucleosides indicates the formation of non-specific complexes with serum albumin. However, the presence of the ethyl group in 8-ethyl-9 N-methyladenine means that in the adenine derivative-serum albumin complex the ethyl chain preserves its dominant role in binding. An advantage of our model is that the π-π interaction between the adenine ring and the amino acids of the protein can be replaced by hydrophobic interaction in the case of complexation of the ethyl adenine derivative.

  10. Point substitutions in albumin genetic variants from Asia.

    PubMed Central

    Arai, K; Madison, J; Shimizu, A; Putnam, F W

    1990-01-01

    Despite their rarity and physiologically neutral character, more inherited structural variants of serum albumin (alloalbumins) are known than for any other human protein except hemoglobin. Including three previously unreported examples described here, we have identified 13 different point substitutions in alloalbumins of Japanese origin. Of these only albumin B and two proalbumins have been reported in other ethnic groups, and these are the most common variants of European origin. Some alloalbumins of Asiatic origin, but not yet identified in Japanese, are present in diverse ethnic groups. An alloalbumin found in indigenes of New Guinea (lysine----asparagine at position 313) is also present in Caucasians of various European descents. Albumin Lambadi, occurring in a tribal group in south India, has a mutation (glutamic acid----lysine at position 501) also found as a rare variant in individuals of diverse ethnic origin resident on four continents. These results suggest that some alloalbumins with the same substitution may have originated by independent mutations in various populations. This, together with the apparent clustering of point substitutions in the protein structure, may reflect hypermutability of the albumin gene. PMID:2404284

  11. Decreased albumin mRNA in immunodeficient wasted' mice

    SciTech Connect

    Libertin, C.R.; Buczek, N.; Weaver, P.; Mobarhan, S.; Woloschak, G.E. Argonne National Lab., IL )

    1991-03-15

    Mice bearing the autosomal recessive gene wst (wst/wst) develop a wasting syndrome' that leads to death by 28-32 days of age. These mice have faulty repair of damage induced by ionizing radiation, immunodeficiency at secretory sites, and neurologic abnormalities. In addition to a progressively more apparent wasted phenotype, wst/wst mice show other features of failure to thrive and malnutrition. Daily body weights of the animals revealed a loss in weight between 25 and 30 days of age, a time during which normal littermates were progressively and rapidly gaining weight. Albumin mRNA levels were measured by dilution dot blot hybridizations of liver-derived RNA preparations from wasted mice, littermates, and parental controls. In all wasted mice, albumin mRNA levels were reduced 5 to 10 fold compared to controls. Northern blots revealed that the albumin mRNA present in wasted mice was normal in length though reduced in amount. These results suggest there may be a relationship between low albumin synthesis and the wasting syndrome of the wst/wst mouse.

  12. Separation of Albumin, Ceruloplasmin, and Transferrin from Human Plasma.

    ERIC Educational Resources Information Center

    Barnes, Grady; Frieden, Earl

    1982-01-01

    Procedures are provided for separating the principal metalloproteins (albumin, ceruloplasmin, and transferrin) from plasma using column chromatographic techniques. The experiment can be completed in two separate three-hour laboratory periods during which column chromatography is illustrated and the effect of pH on charge and affinity of a protein…

  13. Impact of Albumin on Coagulation Competence and Hemorrhage During Major Surgery

    PubMed Central

    Rasmussen, Kirsten C.; Højskov, Michael; Johansson, Pär I.; Kridina, Irina; Kistorp, Thomas; Salling, Lisbeth; Nielsen, Henning B.; Ruhnau, Birgitte; Pedersen, Tom; Secher, Niels H.

    2016-01-01

    Abstract For patients exposed to a massive blood loss during surgery, maintained coagulation competence is important. It is less obvious whether coagulation competence influences bleeding during elective surgery where patients are exposed to infusion of a crystalloid or a colloid. This randomized controlled trial evaluates whether administration of 5% human albumin (HA) or lactated Ringer solution (LR) affects coagulation competence and in turn blood loss during cystectomy due to bladder cancer. Forty patients undergoing radical cystectomy were included to receive either 5% HA (n = 20) or LR (n = 20). Nineteen patients were analyzed in the HA group and 20 patients in the lactated Ringer group. Blinded determination of the blood loss was similar in the 2 groups of patients: 1658 (800–3300) mL with the use of HA and 1472 (700–4330) mL in the lactated Ringer group (P = 0.45). Yet, by thrombelastography (TEG) evaluated coagulation competence, albumin affected clot growth (TEG-angle 69 ± 5 vs 74° ± 3°, P < 0.01) and strength (TEG-MA: 59 ± 6 vs 67 ± 6 mm, P < 0.001) more than LR. Furthermore, by multivariate linear regression analyses reduced TEG-MA was independently associated with the blood loss (P = 0.042) while administration of albumin was related to the changes in TEG-MA (P = 0.029), aPPT (P < 0.022), and INR (P < 0.033). This randomized controlled trial demonstrates that administration of HA does not affect the blood loss as compared to infusion of LR. Also the use of HA did not affect the need for blood transfusion, the incidence of postoperative complications, or the hospital in-stay. Yet, albumin decreases coagulation competence during major surgery and the blood loss is related to TEG-MA rather than to plasma coagulation variables. PMID:26945358

  14. Laser nanostructuring 3-D bioconstruction based on carbon nanotubes in a water matrix of albumin

    NASA Astrophysics Data System (ADS)

    Gerasimenko, Alexander Y.; Ichkitidze, Levan P.; Podgaetsky, Vitaly M.; Savelyev, Mikhail S.; Selishchev, Sergey V.

    2016-04-01

    3-D bioconstructions were created using the evaporation method of the water-albumin solution with carbon nanotubes (CNTs) by the continuous and pulsed femtosecond laser radiation. It is determined that the volume structure of the samples created by the femtosecond radiation has more cavities than the one created by the continuous radiation. The average diameter for multi-walled carbon nanotubes (MWCNTs) samples was almost two times higher (35-40 nm) than for single-walled carbon nanotubes (SWCNTs) samples (20-30 nm). The most homogenous 3-D bioconstruction was formed from MWCNTs by the continuous laser radiation. The hardness of such samples totaled up to 370 MPa at the nanoscale. High strength properties and the resistance of the 3-D bioconstructions produced by the laser irradiation depend on the volume nanotubes scaffold forming inside them. The scaffold was formed by the electric field of the directed laser irradiation. The covalent bond energy between the nanotube carbon molecule and the oxygen of the bovine serum albumin aminoacid residue amounts 580 kJ/mol. The 3-D bioconstructions based on MWCNTs and SWCNTs becomes overgrown with the cells (fibroblasts) over the course of 72 hours. The samples based on the both types of CNTs are not toxic for the cells and don't change its normal composition and structure. Thus the 3-D bioconstructions that are nanostructured by the pulsed and continuous laser radiation can be applied as implant materials for the recovery of the connecting tissues of the living body.

  15. Bovine serum albumin-sodium alkyl sulfates bioconjugates as drug delivery systems.

    PubMed

    Benkő, M; Varga, N; Sebők, D; Bohus, G; Juhász, Á; Dékány, I

    2015-06-01

    Precipitation of bovine serum albumin (BSA) by anionic surfactants with alkyl chains of increasing lengths (octyl, decyl, dodecyl sulfates) was studied at room temperature, at pH 3.0, in isotonic sodium chloride solution. The particle size of albumin, the zeta potential, the surface charge and fluorescent properties of BSA-surfactant composites were investigated concerning addition of increasing amount of surfactant. The thermal stability of the systems was monitored by calorimetric analysis (DSC). The formation of the well-ordered structure in the self-assembly process in liquid phase was studied by XRD measurement. The structure of the precipitated BSA-surfactant nanocomposites was characterized by small-angle X-ray scattering (SAXS). Finally, ibuprofen (IBU) molecules were enclosed in BSA-surfactant bioconjugate systems and the release properties of the drug were investigated. It has been found out that, as a consequence to the increasing number of carbon atoms in the alkyl chains of the surfactant, the structure and the fluorescent properties of the aggregates formed can be controlled due to the increase in the hydrophobicity of BSA-surfactant composites. The bioconjugates are well applicable as carrier to realize controlled release of drug molecules. PMID:25935562

  16. On the molecular interaction between albumin and ibuprofen: An AFM and QCM-D study.

    PubMed

    Eleta-Lopez, Aitziber; Etxebarria, Juan; Reichardt, Niels-Christian; Georgieva, Radostina; Bäumler, Hans; Toca-Herrera, José L

    2015-10-01

    The adsorption of proteins on surfaces often results in a change of their structural behavior and consequently, a loss of bioactivity. One experimental method to study interactions on a molecular level is single molecular force spectroscopy that permits to measure forces down to the pico-newton range. In this work, the binding force between human serum albumin (HSA), covalently immobilized on glutaraldehyde modified gold substrates, and ibuprofen sodium salt was studied by means of single molecular force spectroscopy. First of all, a protocol was established to functionalize atomic force microscopy (AFM) tips with ibuprofen. The immobilization protocol was additionally tested by quartz crystal microbalance with dissipation (QCM-D) and contact angle measurements. AFM was used to characterize the adsorption of HSA on gold substrates, which lead to a packed monolayer of thickness slightly lower than the reported value in solution. Finally, single molecule spectroscopy results were used to characterize the binding force between albumin and ibuprofen and calculate the distance of the transition state (0.6 nm) and the dissociation rate constant (0.055 s(-1)). The results might indicate that part of the adsorbed protein still preserves its functionality upon adsorption. PMID:26218522

  17. Synthesis and characterization of imprinted sorbent for separation of gramine from bovine serum albumin.

    PubMed

    Luliński, Piotr; Klejn, Dorota; Maciejewska, Dorota

    2016-08-01

    The aim of this study was to develop an efficient sorbent for separation of N,N-dimethyl-3-aminomethylindole (gramine) from bovine serum albumin. An imprinting technology was involved in the synthesis of polymers from nine different functional monomers in the presence of ethylene glycol dimethacrylate as a cross-linker. The analysis of binding capacities showed that the highest specificity towards gramine was achieved when 4-vinylbenzoic acid was used as the functional monomer in methanol to form the bulk imprinted polymer, MIP1 (imprinting factor equal to 21.3). The Scatchard analysis of MIP1 showed two classes of binding sites with the dissociation constants Kd equal to 0.105 and 6.52μmolL(-1). The composition and morphology of polymers were defined by (13)C CP/MAS NMR, BET and SEM-EDS analyses. The recognition mechanism of MIP1 was tested using the structurally related bioanalytes, and the dominant role of indole moiety and ethylamine side chain was revealed. A new MISPE protocol was optimized for separation of gramine. The total recoveries on MIP1 were equal to 94±12 % from standard solutions and 85±11 % from bovine serum albumin. PMID:27157767

  18. 21 CFR 862.1645 - Urinary protein or albumin (nonquantitative) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Urinary protein or albumin (nonquantitative) test... Chemistry Test Systems § 862.1645 Urinary protein or albumin (nonquantitative) test system. (a) Identification. A urinary protein or albumin (nonquantitative) test system is a device intended to...

  19. 21 CFR 862.1645 - Urinary protein or albumin (nonquantitative) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Urinary protein or albumin (nonquantitative) test... Chemistry Test Systems § 862.1645 Urinary protein or albumin (nonquantitative) test system. (a) Identification. A urinary protein or albumin (nonquantitative) test system is a device intended to...

  20. 21 CFR 862.1645 - Urinary protein or albumin (nonquantitative) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Urinary protein or albumin (nonquantitative) test... Chemistry Test Systems § 862.1645 Urinary protein or albumin (nonquantitative) test system. (a) Identification. A urinary protein or albumin (nonquantitative) test system is a device intended to...

  1. 21 CFR 862.1645 - Urinary protein or albumin (nonquantitative) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Urinary protein or albumin (nonquantitative) test... Chemistry Test Systems § 862.1645 Urinary protein or albumin (nonquantitative) test system. (a) Identification. A urinary protein or albumin (nonquantitative) test system is a device intended to...

  2. 21 CFR 862.1645 - Urinary protein or albumin (nonquantitative) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Urinary protein or albumin (nonquantitative) test... Chemistry Test Systems § 862.1645 Urinary protein or albumin (nonquantitative) test system. (a) Identification. A urinary protein or albumin (nonquantitative) test system is a device intended to...

  3. Chromatographic and traditional albumin isotherms on cellulose: a model for wound protein adsorption on modified cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Albumin is the most abundant protein found in healing wounds. Traditional and chromatogrpahic protein isotherms of albumin binding on modified cotton fibers are useful in understanding albumin binding to cellulose wound dressings. An important consideration in the design of cellulosic wound dressin...

  4. Uptake of palmitate by hepatocyte suspensions: facilitation by albumin?

    PubMed

    Pond, S M; Davis, C K; Bogoyevitch, M A; Gordon, R A; Weisiger, R A; Bass, L

    1992-05-01

    Albumin-dependent uptake of unbound [3H]palmitic acid by hepatocytes isolated from female rat livers was studied and the experimental results compared with the predictions of a noncompartmental diffusion-reaction theory for the cellular uptake of protein-bound ligands. The outright theoretical predictions involve values for the parameters of the system, some newly measured (hepatocyte radii and the rate constant for the dissociation of palmitate-albumin complex) and some taken from the literature (diffusion coefficients and the equilibrium association constant for the palmitate-albumin complex). The measured unbound clearance of [3H]palmitic acid, defined as the initial uptake velocity divided by the unbound [3H]palmitic acid concentration in the medium, was enhanced 6.6-fold as the concentration of human serum albumin was increased from approximately 5 to 480 microM. This enhancement factor was predicted by the theory, according to which the enhancement reflects codiffusion of bound ligand across the unstirred layer adjacent to the cell membrane and, therefore, an increased delivery of unbound ligand to the cell surface. In contrast, the absolute magnitude of the unbound clearance was consistent with the theory only for the lowest published value for the equilibrium association constant, 15 microM-1. For higher published values (62 and 94 microM-1), the magnitude of the unbound clearance observed experimentally was severalfold higher than that predicted by the theory. If in fact the association constant exceeds 30 microM-1, the data would imply that an albumin-dependent facilitation mechanism exists which enhances the availability of palmitate to the cell over and above the enhancement predicted by the diffusion-reaction theory. PMID:1590397

  5. Albumin testing in urine using a smart-phone

    PubMed Central

    Coskun, Ahmet F.; Nagi, Richie; Sadeghi, Kayvon; Phillips, Stephen; Ozcan, Aydogan

    2013-01-01

    We demonstrate a digital sensing platform, termed Albumin Tester, running on a smart-phone that images and automatically analyses fluorescent assays confined within disposable test tubes for sensitive and specific detection of albumin in urine. This light-weight and compact Albumin Tester attachment, weighing approximately 148 grams, is mechanically installed on the existing camera unit of a smart-phone, where test and control tubes are inserted from the side and are excited by a battery powered laser diode. This excitation beam, after probing the sample of interest located within the test tube, interacts with the control tube, and the resulting fluorescent emission is collected perpendicular to the direction of the excitation, where the cellphone camera captures the images of the fluorescent tubes through the use of an external plastic lens that is inserted between the sample and the camera lens. The acquired fluorescent images of the sample and control tubes are digitally processed within one second through an Android application running on the same cellphone for quantification of albumin concentration in urine specimen of interest. Using a simple sample preparation approach which takes ~ 5 minutes per test (including the incubation time), we experimentally confirmed the detection limit of our sensing platform as 5–10 μg/mL (which is more than 3 times lower than clinically accepted normal range) in buffer as well as urine samples. This automated albumin testing tool running on a smart-phone could be useful for early diagnosis of kidney disease or for monitoring of chronic patients, especially those suffering from diabetes, hypertension, and/or cardiovascular diseases. PMID:23995895

  6. Albumin testing in urine using a smart-phone.

    PubMed

    Coskun, Ahmet F; Nagi, Richie; Sadeghi, Kayvon; Phillips, Stephen; Ozcan, Aydogan

    2013-11-01

    We demonstrate a digital sensing platform, termed Albumin Tester, running on a smart-phone that images and automatically analyses fluorescent assays confined within disposable test tubes for sensitive and specific detection of albumin in urine. This light-weight and compact Albumin Tester attachment, weighing approximately 148 grams, is mechanically installed on the existing camera unit of a smart-phone, where test and control tubes are inserted from the side and are excited by a battery powered laser diode. This excitation beam, after probing the sample of interest located within the test tube, interacts with the control tube, and the resulting fluorescent emission is collected perpendicular to the direction of the excitation, where the cellphone camera captures the images of the fluorescent tubes through the use of an external plastic lens that is inserted between the sample and the camera lens. The acquired fluorescent images of the sample and control tubes are digitally processed within one second through an Android application running on the same cellphone for quantification of albumin concentration in the urine specimen of interest. Using a simple sample preparation approach which takes ~5 min per test (including the incubation time), we experimentally confirmed the detection limit of our sensing platform as 5-10 μg mL(-1) (which is more than 3 times lower than the clinically accepted normal range) in buffer as well as urine samples. This automated albumin testing tool running on a smart-phone could be useful for early diagnosis of kidney disease or for monitoring of chronic patients, especially those suffering from diabetes, hypertension, and/or cardiovascular diseases. PMID:23995895

  7. Effects of Gold Salt Speciation and Structure of Human and Bovine Serum Albumin on the Synthesis and Stability of Gold Nanostructures

    NASA Astrophysics Data System (ADS)

    Miranda, Érica; Tofanello, Aryane; Brito, Adrianne; Lopes, David; Giacomelli, Fernando; Albuquerque, Lindomar; Costa, Fanny; Ferreira, Fabio; Araujo-Chaves, Juliana; de Castro, Carlos; Nantes, Iseli

    2016-03-01

    The present study aimed to investigate the influence of albumin structure and gold speciation on the synthesis of gold nanoparticles (GNPs). The strategy of synthesis was the addition of HAuCl4 solutions at different pH values (3-12) to solutions of human and bovine serum albumins (HSA and BSA) at the same corresponding pH values. Different pH values influence the GNP synthesis due to gold speciation. Besides the inherent effect of pH on the native structure of albumins, the use N-ethylmaleimide (NEM)-treated and heat-denaturated forms of HSA and BSA provided additional insights about the influence of protein structure, net charge, and thiol group approachability on the GNP synthesis. NEM treatment, heating, and the extreme values of pH promoted loss of the native albumin structure. The formation of GNPs indicated by the appearance of surface plasmon resonance (SPR) bands became detectable from fifteen days of the synthesis processes that were carried out with native, NEM-treated and heat-denaturated forms of HSA and BSA, exclusively at pH 6 and 7. After two months of incubation, SPR band was also detected for all synthesis carried out at pH 8.0. The mean values of the hydrodynamic radius (RH) were 24 and 34 nm for GNPs synthesized with native HSA and BSA, respectively. X-ray diffraction (XRD) revealed crystallites of 13 nm. RH, XRD, and zeta potential values were consistent with GNP capping by the albumins. However, the GNPs produced with NEM-treated and heat-denaturated albumins exhibited loss of protein capping by lowering the ionic strength. This result suggests a significant contribution of non-electrostatic interactions of albumins with the GNP surface, in these conditions. The denaturation of proteins exposes hydrophobic groups to the solvent, and these groups could interact with the gold surface. In these conditions, the thiol blockage or oxidation, the latter probably favored upon heating, impaired the formation of a stable capping by thiol coordination

  8. Renal Type A Intercalated Cells Contain Albumin in Organelles with Aldosterone-Regulated Abundance

    PubMed Central

    Jensen, Thomas Buus; Cheema, Muhammad Umar; Szymiczek, Agata; Damkier, Helle Hasager; Praetorius, Jeppe

    2015-01-01

    Albumin has been identified in preparations of renal distal tubules and collecting ducts by mass spectrometry. This study aimed to establish whether albumin was a contaminant in those studies or actually present in the tubular cells, and if so, identify the albumin containing cells and commence exploration of the origin of the intracellular albumin. In addition to the expected proximal tubular albumin immunoreactivity, albumin was localized to mouse renal type-A intercalated cells and cells in the interstitium by three anti-albumin antibodies. Albumin did not colocalize with markers for early endosomes (EEA1), late endosomes/lysosomes (cathepsin D) or recycling endosomes (Rab11). Immuno-gold electron microscopy confirmed the presence of albumin-containing large spherical membrane associated bodies in the basal parts of intercalated cells. Message for albumin was detected in mouse renal cortex as well as in a wide variety of other tissues by RT-PCR, but was absent from isolated connecting tubules and cortical collecting ducts. Wild type I MDCK cells showed robust uptake of fluorescein-albumin from the basolateral side but not from the apical side when grown on permeable support. Only a subset of cells with low peanut agglutinin binding took up albumin. Albumin-aldosterone conjugates were also internalized from the basolateral side by MDCK cells. Aldosterone administration for 24 and 48 hours decreased albumin abundance in connecting tubules and cortical collecting ducts from mouse kidneys. We suggest that albumin is produced within the renal interstitium and taken up from the basolateral side by type-A intercalated cells by clathrin and dynamin independent pathways and speculate that the protein might act as a carrier of less water-soluble substances across the renal interstitium from the capillaries to the tubular cells. PMID:25874770

  9. Vanillin restrains non-enzymatic glycation and aggregation of albumin by chemical chaperone like function.

    PubMed

    Awasthi, Saurabh; Saraswathi, N T

    2016-06-01

    Vanillin a major component of vanilla bean extract is commonly used a natural flavoring agent. Glycation is known to induce aggregation and fibrillation of globular proteins such as albumin, hemoglobin. Here we report the inhibitory potential of vanillin toward early and advanced glycation modification and amyloid like aggregation of albumin based on the determination of both early and advanced glycation and conformational changes in albumin using circular dichroism. Inhibition of aggregation and fibrillation of albumin was determined based on amyloid specific dyes i.e., Congo red and Thioflavin T and microscopic imaging. It was evident that vanillin restrains glycation of albumin and exhibits protective effect toward its native conformation. PMID:26893056

  10. A Monoclonal IgM Protein with Antibody-like Activity for Human Albumin

    PubMed Central

    Hauptman, Stephen; Tomasi, Thomas B.

    1974-01-01

    The serum of a patient (L'ec) with an IgM lambda monoclonal protein was noted to bind albumin on immunoelectrophoresis. Analytical ultracentrifugation of the L'ec serum demonstrated 23S and 12S peaks, but no 4S (albumin) boundary. Immunologically identical 20S and 9S IgM proteins were isolated from the serum and the addition in vitro of either the patient's albumin or albumin isolated from normal serum was shown to reconstitute the 23S and 12S boundaries. The binding of high molecular weight IgM to albumin was demonstated by Sephadex G200 chromatography with 125I-labeled albumin and isolated IgM. Immunoelectrophoresis of the L'ec IgM developed with aggregated albumin (reverse immunoelectrophoresis) also demonstrated the binding of albumin to IgM. That all of the patient's IgM complexed with albumin was shown by affinity chromatography employing an aggregated albumin-immunoadsorbent column. Binding was shown to be of the noncovalent type by polyacrylamide gel electrophoresis in 8 M urea. With hot trypsin proteolysis, Fabμ and Fcμ5 fragments were isolated, and monomer albumin was shown to complex only with the Fabμ fragment by both analytical ultracentrifugation and molecular sieve chromatogaphy employing 125I-labeled Fab fragments. 1 mol of Fabμ fragment bound 1 mol of monomer albumin. Polymers of human albumin, produced by heat aggregation, precipitated with the isolated L'ec protein on gel diffusion analysis and, when coated on sheep red blood cells, gave a hemagglutination titer greater than 1 million with the whole L'ec serum. 50 additional monoclonal IgM, 33 IgA, and 80 IgG sera failed to show precipitation or hemagglutination with aggregated albumin. Native monomer albumin inhibited precipitation only at high concentrations (> 50 mg/ml); dimer albumin or fragments of albumin produced by trypsin digestion inhibited at low concentrations (0.4 mg/ml). No reactivity occurred with the albumin of five other mammalian species, including bovine. The L'ec protein

  11. Buoyancy-activated cell sorting using targeted biotinylated albumin microbubbles.

    PubMed

    Liou, Yu-Ren; Wang, Yu-Hsin; Lee, Chia-Ying; Li, Pai-Chi

    2015-01-01

    Cell analysis often requires the isolation of certain cell types. Various isolation methods have been applied to cell sorting, including fluorescence-activated cell sorting and magnetic-activated cell sorting. However, these conventional approaches involve exerting mechanical forces on the cells, thus risking cell damage. In this study we applied a novel isolation method called buoyancy-activated cell sorting, which involves using biotinylated albumin microbubbles (biotin-MBs) conjugated with antibodies (i.e., targeted biotin-MBs). Albumin MBs are widely used as contrast agents in ultrasound imaging due to their good biocompatibility and stability. For conjugating antibodies, biotin is conjugated onto the albumin MB shell via covalent bonds and the biotinylated antibodies are conjugated using an avidin-biotin system. The albumin microbubbles had a mean diameter of 2 μm with a polydispersity index of 0.16. For cell separation, the MDA-MB-231 cells are incubated with the targeted biotin-MBs conjugated with anti-CD44 for 10 min, centrifuged at 10 g for 1 min, and then allowed 1 hour at 4 °C for separation. The results indicate that targeted biotin-MBs conjugated with anti-CD44 antibodies can be used to separate MDA-MB-231 breast cancer cells; more than 90% of the cells were collected in the MB layer when the ratio of the MBs to cells was higher than 70:1. Furthermore, we found that the separating efficiency was higher for targeted biotin-MBs than for targeted avidin-incorporated albumin MBs (avidin-MBs), which is the most common way to make targeted albumin MBs. We also demonstrated that the recovery rate of targeted biotin-MBs was up to 88% and the sorting purity was higher than 84% for a a heterogenous cell population containing MDA-MB-231 cells (CD44(+)) and MDA-MB-453 cells (CD44-), which are classified as basal-like breast cancer cells and luminal breast cancer cells, respectively. Knowing that the CD44(+) is a commonly used cancer-stem-cell biomarker, our

  12. Buoyancy-Activated Cell Sorting Using Targeted Biotinylated Albumin Microbubbles

    PubMed Central

    Liou, Yu-Ren; Wang, Yu-Hsin; Lee, Chia-Ying; Li, Pai-Chi

    2015-01-01

    Cell analysis often requires the isolation of certain cell types. Various isolation methods have been applied to cell sorting, including florescence-activated cell sorting and magnetic-activated cell sorting. However, these conventional approaches involve exerting mechanical forces on the cells, thus risking cell damage. In this study we applied a novel isolation method called buoyancy-activated cell sorting, which involves using biotinylated albumin microbubbles (biotin-MBs) conjugated with antibodies (i.e., targeted biotin-MBs). Albumin MBs are widely used as contrast agents in ultrasound imaging due to their good biocompatibility and stability. For conjugating antibodies, biotin is conjugated onto the albumin MB shell via covalent bonds and the biotinylated antibodies are conjugated using an avidin-biotin system. The albumin microbubbles had a mean diameter of 2μm with a polydispersity index of 0.16. For cell separation, the MDA-MB-231 cells are incubated with the targeted biotin-MBs conjugated with anti-CD44 for 10 min, centrifuged at 10g for 1 min, and then allowed 1 hour at 4°C for separation. The results indicate that targeted biotin-MBs conjugated with anti-CD44 antibodies can be used to separate MDA-MB-231 breast cancer cells; more than 90% of the cells were collected in the MB layer when the ratio of the MBs to cells was higher than 70:1. Furthermore, we found that the separating efficiency was higher for targeted biotin-MBs than for targeted avidin-incorporated albumin MBs (avidin-MBs), which is the most common way to make targeted albumin MBs. We also demonstrated that the recovery rate of targeted biotin-MBs was up to 88% and the sorting purity was higher than 84% for a a heterogenous cell population containing MDA-MB-231 cells (CD44+) and MDA-MB-453 cells (CD44–), which are classified as basal-like breast cancer cells and luminal breast cancer cells, respectively. Knowing that the CD44+ is a commonly used cancer-stem-cell biomarker, our targeted

  13. Effect of processing methods on colouration of human serum albumin preparations.

    PubMed

    McCann, Karl B; Vucica, Yvonne; Famulari, Sandy; Bertolini, Joseph

    2009-01-01

    Human serum albumin is a well tolerated therapeutic for the treatment of hypovolemia. Despite all commercial human albumin preparations being derived from plasma, these products can have a highly variable colour. Albumin samples derived from ethanol precipitation and chromatographic fractionation procedures were evaluated for bilirubin and biliverdin levels and by spectrophotometry. It was shown that albumin derived from a chromatographic process, which had a bilirubin:albumin ratio similar to that observed in plasma, had a vibrant yellow appearance. The albumin derived from ethanol precipitation had undetectable levels of bilirubin, and the amber colour of this product was attributed mainly to residual haem. The presence of bilirubin during pasteurisation led to oxidation to biliverdin, with a resultant colour change from yellow to yellow/green. Given that the antioxidant properties of bilirubin are well established, it is possible that bilirubin helps protect albumin from oxidation during the pasteurisation step. PMID:18948018

  14. Serum albumin analysis for type II diabetes detection using surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Lin, Jinyong; Cao, Gang; Lin, Juqiang; Liu, Nenrong; Liao, Fadian; Ruan, Qiuyong; Wu, Shanshan; Huang, Zufang; Li, Ling; Chen, Rong

    2014-09-01

    Surface-enhanced Raman scattering (SERS) spectroscopy combined with membrane electrophoresis (ME) was firstly employed to detect albumin variation in type II diabetic development. Albumin was first purified from human serum by ME and then mixed with silver nanoparticles to perform SERS spectral analysis. SERS spectra were obtained from blood albumin samples of 20 diabetic patients and 19 healthy volunteers. Subtle but discernible changes in the acquired mean spectra of the two groups were observed. Tentative assignment of albumin SERS bands indicated specific structural changes of albumin molecule with diabetic development. Meanwhile, PCA-LDA diagnostic algorithms were employed to classify the two kinds of albumin SERS spectra, yielding the diagnostic sensitivity of 90% and specificity of 94.7%. The results from this exploratory study demonstrated that the EM-SERS method in combination with multivariate statistical analysis has great potential for the label-free detection of albumin variation for improving type II diabetes screening.

  15. Insulin Is Required to Maintain Albumin Expression by Inhibiting Forkhead Box O1 Protein.

    PubMed

    Chen, Qing; Lu, Mingjian; Monks, Bobby R; Birnbaum, Morris J

    2016-01-29

    Diabetes is accompanied by dysregulation of glucose, lipid, and protein metabolism. In recent years, much effort has been spent on understanding how insulin regulates glucose and lipid metabolism, whereas the effect of insulin on protein metabolism has received less attention. In diabetes, hepatic production of serum albumin decreases, and it has been long established that insulin positively controls albumin gene expression. In this study, we used a genetic approach in mice to identify the mechanism by which insulin regulates albumin gene transcription. Albumin expression was decreased significantly in livers with insulin signaling disrupted by ablation of the insulin receptor or Akt. Concomitant deletion of Forkhead Box O1 (Foxo1) in these livers rescued the decreased albumin secretion. Furthermore, activation of Foxo1 in the liver is sufficient to suppress albumin expression. These results suggest that Foxo1 acts as a repressor of albumin expression. PMID:26668316

  16. Fluorescence study on the interaction of human serum albumin with Butein in liposomes

    NASA Astrophysics Data System (ADS)

    Toprak, Mahmut

    2016-02-01

    The interaction of Butein with human serum albumin in L-egg lecithin phosphatidycholine (PC) liposome has been investigated by fluorescence and absorption spectroscopy. The results of the fluorescence measurement indicated that Butein effectively quenched the intrinsic fluorescence of HSA via static quenching. The Stern-Volmer plots in all the liposome solutions showed a positive deviation from the linearity. According to the thermodynamic parameters, the hydrophobic interactions appeared be the major interaction forces between Butein and HSA. The effect of Butein on the conformation of HSA was also investigated by the synchronous fluorescence under the same experimental conditions. In addition, the partition coefficient of the Butein in the PC liposomes was also determined by using the fluorescence quenching process. The obtained results can be of biological significance in pharmacology and clinical medicine.

  17. Spectrometry researches on interaction and sonodynamic damage of riboflavin (RF) to bovine serum albumin (BSA)

    NASA Astrophysics Data System (ADS)

    Wang, Zhiqiu; Li, Jushi; Wang, Jun; Zou, Mingming; Wang, Siyu; Li, Ying; Kong, Yumei; Xia, Lixin

    2012-02-01

    In this paper, the riboflavin (RF) was used to study the interaction and sonodynamic damage to bovine serum albumin (BSA) by fluorescence and UV-vis spectroscopy. The results showed that the RF could efficiently bind to BSA in aqueous solution. Under ultrasonic irradiation, the RF could obviously damage the BSA. In addition, synchronous fluorescence spectroscopy revealed that the RF showed more accessible to tryptophan (Trp) residues than to tyrosine (Tyr) residues. Also, it damaged Trp residues more seriously than Tyr residues under ultrasonic irradiation. At last, the generation of reactive oxygen species (ROS) in sonodynamic process was estimated by the method of Oxidation-Extraction Spectrometry (OES). And then, several radical scavengers were used to determine the kind of ROS. It was found that at least the singlet oxygen ( 1O 2) and hydroxyl radicals ( rad OH) were generated.

  18. A calorimetric study on interactions of colchicine with human serum albumin

    NASA Astrophysics Data System (ADS)

    Zhao, Qiang; Xu, Xiang-Yu; Sun, Xiang-Jun; Liu, Min; Sun, De-Zhi; Li, Lin-Wei

    2009-08-01

    Interaction of colchicine (COL) with human serum albumin (HSA) in buffer solutions (pH 7.2) has been investigated by isothermal titration calorimetry (ITC) combined with circular dichroism (CD) and UV-vis spectra. Heats of the interactions have been determined at 298.15 K. Based on the calorimetric data and reasonable suppositions for the bio-macromolecule - ligand binding process, the equilibrium constants, standard changes of enthalpy, entropy and Gibbs free energy of the processes are obtained. The results show that there are two classes of ligand binding sites. The first-class binding is mainly driven by entropy, while the second-class binding is synergistically driven by entropy and enthalpy. Circular dichroism (CD) and UV-vis spectra show that COL can change the secondary structure of HSA molecule.

  19. Studying the denaturation of bovine serum albumin by a novel approach of difference-UV analysis.

    PubMed

    Nikolaidis, Athanasios; Moschakis, Thomas

    2017-01-15

    A novel approach in the analysis of difference-UV spectrophotometric data for determining the heat denaturation degree of bovine serum albumin (BSA) was assessed. Five different parameters of difference-UV spectra were obtained by subtracting spectra of unheated and denatured protein solutions at different temperature-time combinations. BSA was found to exhibit a maximum degree of heat denaturation of about 17% compared to the complete unfolding caused by 6M guanidine hydrochloride. This low degree of heat denaturation is probably caused by the aggregation of the initially unfolded protein molecules. The kinetic analysis exhibited discontinuities in the Arrhenius plots, distinguishing the unfolding and aggregation phases of the denaturation process, whereas such a discrimination could not be obtained by differential scanning calorimetry analyses. The proposed method is accurate, fast, simple and sensitive enough to detect changes in the protein heat denaturation even at short temperature-time intervals. PMID:27542472

  20. Serum Albumin-Alginate Microparticles Prepared by Transacylation: Relationship between Physicochemical, Structural and Functional Properties.

    PubMed

    Hadef, Imane; Rogé, Barbara; Edwards-Lévy, Florence

    2015-08-10

    Our laboratory develops a method of microencapsulation using a transacylation reaction in a water-in-oil (W/O) emulsion. The method is based on the creation of amide bonds between free amine functions of a protein (human serum albumin (HSA)) and ester groups of propylene glycol alginate (PGA) in the inner aqueous phase after alkalization. The aim of this work is to study the influence of physicochemical properties of HSA-PGA mixtures on microparticle characteristics. Microparticles were prepared varying the concentrations of PGA and HSA, then characterized (inner structure, size, swelling rate, release kinetics). PGA and each polymer mixture used in the microencapsulation procedure were examined in order to elucidate the mechanism of microstructure formation. It was found that the morphology and functional properties of HSA-alginate microparticles were related to the two polymer concentrations in the aqueous solution. Actually, the polymer concentration variations led to physicochemical changes, which affected the microparticle structure and functional properties. PMID:26121308

  1. Ellipsometric studies of synthetic albumin-binding chitosan-derivatives and selected blood plasma proteins

    NASA Astrophysics Data System (ADS)

    Sarkar, Sabyasachi

    This dissertation summarizes work on the synthesis of chitosan-derivatives and the development of ellipsometric methods to characterize materials of biological origin. Albumin-binding chitosan-derivatives were synthesized via addition reactions that involve amine groups naturally present in chitosan. These surfaces were shown to have an affinity towards human serum albumin via ELISA, UV spectroscopy and SDS PAGE. Modified surfaces were characterized with IR ellipsometry at various stages of their synthesis using appropriate optical models. It was found that spin cast chitosan films were anisotropic in nature. All optical models used for characterizing chitosan-derivatives were thus anisotropic. Chemical signal dependence on molecular structure and composition was illustrated via IR spectroscopic ellipsometry (IRSE). An anisotropic optical model of an ensemble of Lorentz oscillators were used to approximate material behavior. The presence of acetic acid in spin-cast non-neutralized chitosan samples was thus shown. IRSE application to biomaterials was also demonstrated by performing a step-wise chemical characterizations during synthesis stages. Protein adsorbed from single protein solutions on these modified surfaces was monitored by visible in-situ variable wavelength ellipsometry. Based on adsorption profiles obtained from single protein adsorption onto silicon surfaces, lumped parameter kinetic models were developed. These models were used to fit experimental data of immunoglobulin-G of different concentrations and approximate conformational changes in fibrinogen adsorption. Biomaterial characterization by ellipsometry was further extended to include characterization of individual protein solutions in the IR range. Proteins in an aqueous environment were characterized by attenuated total internal reflection (ATR) IR ellipsometry using a ZnSe prism. Parameterized dielectric functions were created for individual proteins using Lorentz oscillators. These

  2. Absorptive-mediated endocytosis of cationized albumin and a beta-endorphin-cationized albumin chimeric peptide by isolated brain capillaries. Model system of blood-brain barrier transport

    SciTech Connect

    Kumagai, A.K.; Eisenberg, J.B.; Pardridge, W.M.

    1987-11-05

    Cationized albumin (pI greater than 8), unlike native albumin (pI approximately 4), enters cerebrospinal fluid (CSF) rapidly from blood. This suggests that a specific uptake mechanism for cationized albumin may exist at the brain capillary wall, i.e. the blood-brain barrier. Isolated bovine brain capillaries rapidly bound cationized (/sup 3/H)albumin and approximately 70% of the bound radioactivity was resistant to mild acid wash, which is assumed to represent internalized peptide. Binding was saturable and a Scatchard plot gave a maximal binding capacity (Ro) = 5.5 +/- 0.7 micrograms/mgp (79 +/- 10 pmol/mgp), and a half-saturation constant (KD) = 55 +/- 8 micrograms/ml (0.8 +/- 0.1 microM). The binding of cationized (/sup 3/H)albumin (pI = 8.5-9) was inhibited by protamine, protamine sulfate, and polylysine (molecular weight = 70,000) with a Ki of approximately 3 micrograms/ml for all three proteins. The use of cationized albumin in directed delivery of peptides through the blood-brain barrier was examined by coupling (/sup 3/H)beta-endorphin to unlabeled cationized albumin (pI = 8.5-9) using the bifunctional reagent, N-succinimidyl 3-(2-pyridyldithio)proprionate. The (/sup 3/H)beta-endorphin-cationized albumin chimeric peptide was rapidly bound and endocytosed by isolated bovine brain capillaries, and this was inhibited by unlabeled cationized albumin but not by unconjugated beta-endorphin or native bovine albumin. Cationized albumin provides a new tool for studying absorptive-mediated endocytosis at the brain capillary and may also provide a vehicle for directed drug delivery through the blood-brain barrier.

  3. Recent advancements in erythrocytes, platelets, and albumin as delivery systems

    PubMed Central

    Xu, Peipei; Wang, Ruju; Wang, Xiaohui; Ouyang, Jian

    2016-01-01

    In the past few years, nanomaterial-based drug delivery systems have been applied to enhance the efficacy of therapeutics and to alleviate negative effects through the controlled delivery of targeting and releasing agents. However, few drug carriers can achieve high targeting efficacy, even when targeting modalities and surface markers are introduced. Immunological problems have also limited their wide applications. Biological drug delivery systems, such as erythrocytes, platelets, and albumin, have been extensively investigated because of their unique properties. In this review, erythrocytes, platelets, and albumin are described as efficient drug delivery systems. Their properties, applications, advantages, and limitations in disease treatment are explained. This review confirms that these systems can be used to facilitate a specific, biocompatible, and smart drug delivery. PMID:27274282

  4. Recent topics in chemical and clinical research on glycated albumin.

    PubMed

    Ueda, Yuki; Matsumoto, Hideyuki

    2015-03-01

    The measuring method for glycated albumin (GA) has been developed as a new glycemic control marker since the beginning of the 21st century. Since GA has an advantage in reflecting glycemic status over a shorter period than hemoglobin A1c (HbA1c), much research and many reviews have been reported. However, so far there have been few reports on glycation sites based on the tertiary structure of human serum albumin (HSA) and the comparison of glycation rates between GA and HbA1c in detail. The present review discusses how the glycation sites of lysine residues in HSA are modified with glucose, whereas the glycation sites of lysine residues are located inside of HSA as well as the direct comparison of glycation rates between GA and HbA1c using human blood. Moreover, the most recent clinical researches on GA are described. PMID:25614014

  5. Curcumin-incorporated albumin nanoparticles and its tumor image

    NASA Astrophysics Data System (ADS)

    Gong, Guangming; Pan, Qinqin; Wang, Kaikai; Wu, Rongchun; Sun, Yong; Lu, Ying

    2015-01-01

    Albumin is an ideal carrier for hydrophobic drugs. This paper reports a facile route to develop human serum albumin (HSA)-curcumin (CCM) nanoparticles, in which β-mercaptoethanol (β-ME) acted as an inducer and CCM acted as a bridge. Fluorescence quenching and conformational changes in HSA-CCM nanoparticles occurred during assembly. Disulfide bonds and hydrophobic interactions may play a key role in assembly. HSA-CCM nanoparticles were about 130 nm in size, and the solubility of CCM increased by more than 500 times. The HSA-CCM nanoparticles could accumulate at the cytoplasm of tumor cells and target the tumor tissues. Therefore, HSA nanoparticles fabricated by β-ME denaturation are promising nanocarriers for hydrophobic substances from chemotherapy drugs to imaging probes.

  6. Iodide and albumin kinetics in normal canine wrists and knees

    SciTech Connect

    Simkin, P.A.; Benedict, R.S. )

    1990-01-01

    The clearance rates of free iodide and of radioiodinated serum albumin were measured in the knee and wrist joints of 9 normal adult dogs. Iodide clearance from the knee was 3 times greater than that from the wrist. In contrast, radioiodinated serum albumin clearance from the knee was only slightly greater than that from the wrist. Interpreted as respective indices of effective synovial plasma flow and lymphatic drainage, these values indicate that the filtration fraction is normally greater in microvessels of the wrist than in those of the knee. These findings complement the results of companion studies of Starling forces that indicate a higher pressure microvascular bed in the wrist than in the knee.

  7. Tamoxifen and curcumin binding to serum albumin. Spectroscopic study

    NASA Astrophysics Data System (ADS)

    Maciążek-Jurczyk, M.; Maliszewska, M.; Pożycka, J.; Równicka-Zubik, J.; Góra, A.; Sułkowska, A.

    2013-07-01

    Tamoxifen (TMX) is widely used for the breast cancer treatment and is known as chemopreventive agent. Curcumin (CUR) is natural phenolic compound with broad spectrum of biological activity e.g. anti-inflammatory, antimicrobial, antiviral, antifungal and chemopreventive. Combination of tamoxifen and curcumin could be more effective with lower toxicity than each agent alone in use for the treatment or chemoprevention of breast cancer. Binding of drugs to serum albumin is an important factor, which determines toxicity and therapeutic dosage of the drugs. When two drugs are administered together the competition between them for the binding site on albumin can result in a decrease in bound fraction and an increase in the concentration of free biologically active fraction of drug.

  8. Microheterogeneity in Frozen Protein Solutions

    PubMed Central

    Twomey, Alan; Kurata, Kosaku; Nagare, Yutaka; Takamatsu, Hiroshi; Aksan, Alptekin

    2015-01-01

    In frozen and lyophilized systems, the biological to be stabilized (e.g. therapeutic protein, biomarker, drug-delivery vesicle) and the cryo-/lyoprotectant should be co-localized for successful stabilization. During freezing and drying, many factors cause physical separation of the biological from the cryo-/lyoprotectant, called microheterogeneity (MH), which may result in poor stabilization efficiency. We have developed a novel technique that utilized confocal Raman microspectroscopy in combination with counter-gradient freezing to evaluate the effect of a wide range of freezing temperatures (−20 < TF < 0°C) on the MH generated within a frozen formulation in only a few experiments. The freezing experiments conducted with a model system (albumin and trehalose) showed the presence of different degrees of MH in the freeze-concentrated liquid (FCL) in all solutions tested. Mainly, albumin tended to accumulate near the ice interface, where it was physically separated from the cryoprotectant. In frozen 10 wt% trehalose solutions, heterogeneity in FCL was relatively low at any TF. In frozen 20 wt% trehalose solutions, the optimum albumin to trehalose ratio in the FCL can only be ensured if the solution was frozen within a narrow range of temperatures (−16 < TF < −10°C). In the 30 wt% trehalose solutions, freezing within a much more narrow range (−12 < TF < −10°C) was needed to ensure a fairly homogeneous FCL. The method developed here will be helpful for the development of uniformly frozen and stable formulations and freezing protocols for biological as MH is presumed to directly impact stability. PMID:25888798

  9. Microheterogeneity in frozen protein solutions.

    PubMed

    Twomey, Alan; Kurata, Kosaku; Nagare, Yutaka; Takamatsu, Hiroshi; Aksan, Alptekin

    2015-06-20

    In frozen and lyophilized systems, the biological to be stabilized (e.g. therapeutic protein, biomarker, drug-delivery vesicle) and the cryo-/lyo-protectant should be co-localized for successful stabilization. During freezing and drying, many factors cause physical separation of the biological from the cryo-/lyo-protectant, called microheterogeneity (MH), which may result in poor stabilization efficiency. We have developed a novel technique that utilized confocal Raman microspectroscopy in combination with counter-gradient freezing to evaluate the effect of a wide range of freezing temperatures (-20albumin and trehalose) showed the presence of different degrees of MH in the freeze-concentrated liquid (FCL) in all solutions tested. Mainly, albumin tended to accumulate near the ice interface, where it was physically separated from the cryoprotectant. In frozen 10wt% trehalose solutions, heterogeneity in FCL was relatively low at any TF. In frozen 20wt% trehalose solutions, the optimum albumin to trehalose ratio in the FCL can only be ensured if the solution was frozen within a narrow range of temperatures (-16solutions, freezing within a much more narrow range (-12

  10. Binding of several benzodiazepines to bovine serum albumin: Fluorescence study

    NASA Astrophysics Data System (ADS)

    Machicote, Roberta G.; Pacheco, María E.; Bruzzone, Liliana

    2010-10-01

    The interactions of lorazepam, oxazepam and bromazepam with bovine serum albumin (BSA) were studied by fluorescence spectrometry. The Stern-Volmer quenching constants and corresponding thermodynamic parameters Δ H, Δ G and Δ S were calculated. The binding constants and the number of binding sites were also investigated. The distances between the donor (BSA) and the acceptors (benzodiazepines) were obtained according to fluorescence resonance energy transfer and conformational changes of BSA were observed from synchronous fluorescence spectra.

  11. Reactions of trimethylphosphine analogues of auranofin with bovine serum albumin

    SciTech Connect

    Isab, A.A.; Shaw, C.F. III; Hoeschele, J.D.; Locke, J.

    1988-10-05

    The reactions of bovine serum albumin (BSA) with (trimethylphosphine)(2,3,4,6-tetra-O-acetyl-1-thio-..beta..-D-glucopyranosato-S)gold(I), Me/sub 3/PAuSAtg, and its chloro analogue, Me/sub 3/PAuCl, were studied to develop insights into the role of the phosphine ligand in the serum chemistry of the related antiarthritic drug auranofin (triethylphosphine)(2,3,4,6-tetra-O-acetyl-1-thio-..beta..-D-glucopyranosato-S)gold(I). /sup 31/P NMR spectroscopy, protein modification, and gel-exclusion chromatography methods were employed. Comparison of the reactions of the methyl derivatives to the previously reported reactions of auranofin and Et/sub 3/PAuCl with BSA demonstrated that similar chemical species are formed but revealed three major differences. Despite these differences, the results for the methyl analogues provide important confirmation for previously developed chemical models of auranofin reactions in serum. Me/sub 3/PO was not observed in reaction mixtures lacking tetraacetylthioglucose (AtgSH); this result affirms the role of AtgSH, displaced by the reaction of Me/sub 3/PAuSAtg at Cys-34, in the generation of the phosphine oxide (an important metabolite in vivo). The weak binding sites on albumin react with Me/sub 3/PAuCl, but not Me/sub 3/PAuSAtg, demonstrating the importance of the strength and reactivity of the anionic ligand-gold bond on the reactions of auranofin analogues. The gold binding capacity of albumin is enhanced after Me/sub 3/PO is formed, consistent with reductive cleavage of albumin disulfide bonds by trimethylphosphine. 24 references, 2 figures, 3 tables.

  12. Increased regional vascular albumin permeation in the rat during anaphylaxis

    SciTech Connect

    Leng, W.; Chang, K.; Williamson, J.R.; Jakschik, B.A.

    1989-03-15

    The changes in vascular albumin permeation induced by systemic anaphylaxis were studied simultaneously in 21 different tissues of the same animal. Before Ag challenge sensitized rats were injected i.v. with 125I-albumin (test tracer), 51Cr-RBC (vascular space marker) and 57Co-EDTA (extravascular space marker). The index of vascular permeation used was the tissue to blood isotope ratio (tbir), which was obtained by dividing the ratio of 125I/51Cr counts in each tissue by the ratio of the same isotopes in the arterial blood sample. After Ag challenge, the increase in the tbir varied considerably among the different tissues. The most pronounced increase was noted in the lymph node (ninefold) followed by the aorta and mesentery (six- to sevenfold) and the various parts of the gastrointestinal tract (four- to sixfold). In the skin less than skeletal muscle less than lung less than liver and eye two- to fourfold increases occurred. Relatively minor increases in albumin permeation (less than twofold) were observed in the brain less than kidney less than heart and less than spleen. The testis was the only organ in which no significant change occurred. For some of the tissues there was also an increase in the tbir for 57Co/51Cr (an index of the extracellular fluid space) suggesting edema formation. The highest increase was noted in the aorta (fourfold). Minor increases occurred in the atrium of the heart, stomach, duodenum, and lymph nodes. There was also a 36% increase in hematocrit. Therefore, systemic anaphylaxis caused extensive extravasation of albumin and hemoconcentration.

  13. Immunodetection of Serum Albumin Adducts as Biomarkers for Organophosphorus Exposure

    PubMed Central

    Chen, Sigeng; Zhang, Jun; Lumley, Lucille

    2013-01-01

    A major challenge in organophosphate (OP) research has been the identification and utilization of reliable biomarkers for the rapid, sensitive, and efficient detection of OP exposure. Although Tyr 411 OP adducts to human serum albumin (HSA) have been suggested to be one of the most robust biomarkers in the detection of OP exposure, the analysis of HSA-OP adduct detection has been limited to techniques using mass spectrometry. Herein, we describe the procurement of two monoclonal antibodies (mAb-HSA-GD and mAb-HSA-VX) that recognized the HSA Tyr 411 adduct of soman (GD) or S-[2-(diisopropylamino)ethyl]-O-ethyl methylphosphonothioate (VX), respectively, but did not recognize nonphosphonylated HSA. We showed that mAb-HSA-GD was able to detect the HSA Tyr 411 OP adduct at a low level (i.e., human blood plasma treated with 180 nM GD) that could not be detected by mass spectrometry. mAb-HSA-GD and mAb-HSA-VX showed an extremely low-level detection of GD adducted to HSA (on the order of picograms). mAb-HSA-GD could also detect serum albumin OP adducts in blood plasma samples from different animals administered GD, including rats, guinea pigs, and monkeys. The ability of the two antibodies to selectively recognize nerve agents adducted to serum albumin suggests that these antibodies could be used to identify biomarkers of OP exposure and provide a new biologic approach to detect OP exposure in animals. PMID:23192655

  14. Superior serum half life of albumin tagged TNF ligands

    SciTech Connect

    Mueller, Nicole; Schneider, Britta; Pfizenmaier, Klaus; Wajant, Harald

    2010-06-11

    Due to their immune stimulating and apoptosis inducing properties, ligands of the TNF family attract increasing interest as therapeutic proteins. A general limitation of in vivo applications of recombinant soluble TNF ligands is their notoriously rapid clearance from circulation. To improve the serum half life of the TNF family members TNF, TWEAK and TRAIL, we genetically fused soluble variants of these molecules to human serum albumin (HSA). The serum albumin-TNF ligand fusion proteins were found to be of similar bioactivity as the corresponding HSA-less counterparts. Upon intravenous injection (i.v.), serum half life of HSA-TNF ligand fusion proteins, as determined by ELISA, was around 15 h as compared to approximately 1 h for all of the recombinant control TNF ligands without HSA domain. Moreover, serum samples collected 6 or 24 h after i.v. injection still contained high TNF ligand bioactivity, demonstrating that there is only limited degradation/inactivation of circulating HSA-TNF ligand fusion proteins in vivo. In a xenotransplantation model, significantly less of the HSA-TRAIL fusion protein compared to the respective control TRAIL protein was required to achieve inhibition of tumor growth indicating that the increased half life of HSA-TNF ligand fusion proteins translates into better therapeutic action in vivo. In conclusion, our data suggest that genetic fusion to serum albumin is a powerful and generally applicable mean to improve bioavailability and in vivo activity of TNF ligands.

  15. Albumin extravasation rates in tissues of anesthetized and unanesthetized rats

    SciTech Connect

    Renkin, E.M.; Joyner, W.L.; Gustafson-Sgro, M.; Plopper, G.; Sibley, L.

    1989-05-01

    Bovine serum albumin (BSA) labeled with /sup 131/I was injected intravenously in chronically prepared, unanesthetized rats and into pentobarbital-anesthetized rats that had received 2 ml 5% BSA to help sustain plasma volume. Initial uptake rates (clearances) in skin, skeletal muscles, diaphragm, and heart (left ventricle) were measured over 1 h. BSA labeled with /sup 125/I was injected terminally to correct for intravascular /sup 131/I-BSA. Observed clearances were in the following order in both groups of animals: heart much greater than diaphragm approximately equal to skin greater than resting skeletal muscles. Differences between unanesthetized and anesthetized animals were small and inconsistently directed. Our results suggest that the lower albumin clearances reported in the literature for anesthetized rats are not the result of their immobility or any direct effect of anesthesia on albumin transport in these tissues. The lower transport rates appear to result indirectly from changes produced by anesthesia and/or surgery in controllable parameters such as plasma volume and intravascular protein mass.

  16. Pru du 2S albumin or Pru du vicilin?

    PubMed

    Garino, Cristiano; De Paolis, Angelo; Coïsson, Jean Daniel; Arlorio, Marco

    2015-06-01

    A short partial sequence of 28 amino acids is all the information we have so far about the putative allergen 2S albumin from almond. The aim of this work was to analyze this information using mainly bioinformatics tools, in order to verify its rightness. Based on the results reported in the paper describing this allergen from almond, we analyzed the original data of amino acids sequencing through available software. The degree of homology of the almond 12kDa protein with any other known 2S albumin appears to be much lower than the one reported in the paper that firstly described it. In a publicly available cDNA library we discovered an expressed sequence tag which translation generates a protein that perfectly matches both of the sequencing outputs described in the same paper. A further analysis indicated that the latter protein seems to belong to the vicilin superfamily rather than to the prolamin one. The fact that also vicilins are seed storage proteins known to be highly allergenic would explain the IgE reactivity originally observed. Based on our observations we suggest that the IgE reactive 12kDa protein from almond currently known as Pru du 2S albumin is in reality the cleaved N-terminal region of a 7S vicilin like protein. PMID:25854802

  17. The interaction between bovine serum albumin and surfactants.

    PubMed Central

    Jones, M N; Skinner, H A; Tipping, E

    1975-01-01

    1. Potassium n-decyl phosphate binds exothermically to bovine serum albumin at pH 7.0 to form a specific complex containing approx. 60 phosphate anions. 2. The formation of the complex is accompanied by changes in the u.v. difference spectrum of the protein. 3. At higher phosphate concentrations (above 0.4mM) surfactant molecules continue to be bound, and the protein undergoes a gross change in conformation. 4. n-Dodecyltri-methylammonium bromide binds endothermically to bovine serum albumin at pH7.0 but the extent of binding for a given free surfactant concentration is less than for the phosphate surfactant. 5. Binding is accompanied by a small change in the specific viscosity and by changes in the u.v. difference spectrum of the protein. 6. It is suggested that over the surfactant concentration ranges studied n-decyl phosphate ions first bind to the C-terminal part of the protein and then to the more compact N-terminal part whereas n-dodecyltrimethylammonium ions bind only to the C-terminal part of bovine serum albumin. PMID:1180891

  18. Effect of tribology processes on adsorption of albumin

    NASA Astrophysics Data System (ADS)

    Yan, Yu; Yang, Hongjuan; Wang, Linghe; Su, Yanjing; Qiao, Lijie

    2016-03-01

    As soon as artificial joint replacements are implanted into patients, the adsorption of proteins can occur. Joint implants operate in a protein-rich and relatively corrosive environment under tribological contact. The contacted area acted as an anodic part and the rest of the surface was more cathodic. Therefore, the adsorption of proteins is different in and outside the wear track. Adsorbed proteins would denature during rubbing and a tribofilm could form. The tribofilm can lubricate the surface and act as a barrier to corrosion damage. However, to observe the adsorption of proteins in situ has always been a challenge. Scanning Kelvin probe force microscope (SKPFM) was used to study the adsorption of albumin on the surface of CoCrMo alloy under simulated tribology movement. Fluorescence microscopy (FM) was employed to reveal the protein molecules in the wear scar. It was found that albumin molecules can decrease the surface potential and accelerate the corrosion process. In the wear track, albumin denatured and changed the surface potential as time progressed.

  19. Effect of alcohol aggregation on the retention factors of chiral solutes with an amylose-based sorbent: modeling and implications for the adsorption mechanism.

    PubMed

    Tsui, Hung-Wei; Franses, Elias I; Wang, Nien-Hwa Linda

    2014-02-01

    Various displacement models in the literature have been widely used for understanding the adsorption mechanisms of solutes in various chromatography systems. The models were used for describing the often-observed linear plots of the logarithms of the retention factor versus the logarithms of the polar modifier concentration CI(0). The slopes of such a plot was inferred to be equal to the number of the displaced modifier molecules upon adsorption of one solute molecule, and were generally found to be greater than 1. In this study, the retention factors of four structurally related chiral solutes, ethyl lactate (EL), methyl mandelate (MM), benzoin (B), and pantolactone (PL), were measured for the amylose tris[(S)-α-methylbenzylcarbamate] sorbent, or AS, as a function of the concentration of isopropanol (IPA) in n-hexane. With increasing IPA concentration CI(0), the slopes increase from less than 1, at a concentration range from 0.13 to 1.3M, to slightly more than 1 at higher concentrations. Such slopes cannot be explained by the conventional retention models. It was found previously for monovalent solutes that such slopes can only be explained when the aggregation of the mobile phase modifier, isopropyl alcohol, was accounted for. A new retention model is presented here, accounting for alcohol aggregation, multivalent solute adsorption, multivalent solute-alcohol complexation, alcohol adsorption, and solute intra hydrogen-bonding, which occur in these four solutes. The slope is found to be controlled by three key dimensionless groups, the fraction of the sorbent binding sites covered by IPA, the fraction of the solute molecules in complex form, and the fraction of the IPA molecules in aggregate form. The limiting slope at a very high IPA concentration is equal to the value of (x+y)/n, where x is the number of the solute-sorbent binding sites and y is the number of the alcohol molecules in the solute-alcohol complex, and n is the alcohol aggregation number. The model

  20. REPORT ON THE GEOELECTRICAL DETECTION OF SURFACTANT ENHANCED AQUIFER REMEDIATION OF PCE: PROPERTY CHANGES IN AQUEOUS SOLUTIONS DUE TO SURFACTANT TREATMENT OF PERCHLOROETHYLENE: IMPLICATIONS TO GEOPHYSICAL MEASUREMENTS

    EPA Science Inventory

    Select physicochemical properties of nine surfactants which are conventionally used in the remediation of perchloroethylene (PCE, a.k.a. tetrachloroethene) were evaluated with varying concentrations of PCE and indicator dyes in aqueous solutions using a response surface quadrati...

  1. 25-Hydroxyvitamin D isomerizes to pre-25-hydroxyvitamin D in solution: considerations for calibration in clinical measurements.

    PubMed

    Bedner, Mary; Lippa, Katrice A

    2015-10-01

    Reference standards for the vitamin D metabolites 25-hydroxyvitamin D3, 25-hydroxyvitamin D2, and 3-epi-25-hydroxyvitamin D3 were evaluated using liquid chromatography (LC) with ultraviolet (UV) absorbance and mass spectrometric (MS) detection to assess purity. The chromatograms for solutions of all three 25(OH)D compounds, obtained using a pentafluorophenyl (PFP) stationary phase, revealed peaks that increased in area over time and had MS spectra that were nearly identical to the parent compound, indicating isomers had formed in solution that were unrelated to the reference standard purity. However, when the purity evaluations were completed with a cyanopropyl stationary phase, the isomeric products coeluted with the parent compounds and were not observable. The rates of formation of the isomeric products were found to increase when heated and were confirmed to be pre-25-hydroxyvitamin D compounds using spectral information from both MS detection and nuclear magnetic resonance (NMR) spectroscopy. The rates of conversion of 25(OH)D3 to pre-25(OH)D3 was studied in solutions of ethanol and bovine serum albumin (BSA) in phosphate-buffered saline (PBS). The solutions prepared with BSA/PBS were found to form twice as much pre-25(OH)D3 as the solutions in ethanol. The isomerization of 25(OH)D in solution has implications for calibration of 25(OH)D in clinical measurements, which are discussed. PMID:26359234

  2. Novel Transgenic Mouse Model for Studying Human Serum Albumin as a Biomarker of Carcinogenic Exposure.

    PubMed

    Sheng, Jonathan; Wang, Yi; Turesky, Robert J; Kluetzman, Kerri; Zhang, Qing-Yu; Ding, Xinxin

    2016-05-16

    Albumin is a commonly used serum protein for studying human exposure to xenobiotic compounds, including therapeutics and environmental pollutants. Often, the reactivity of albumin with xenobiotic compounds is studied ex vivo with human albumin or plasma/serum samples. Some studies have characterized the reactivity of albumin with chemicals in rodent models; however, differences between the orthologous peptide sequences of human and rodent albumins can result in the formation of different types of chemical-protein adducts with different interaction sites or peptide sequences. Our goal is to generate a human albumin transgenic mouse model that can be used to establish human protein biomarkers of exposure to hazardous xenobiotics for human risk assessment via animal studies. We have developed a human albumin transgenic mouse model and characterized the genotype and phenotype of the transgenic mice. The presence of the human albumin gene in the genome of the model mouse was confirmed by genomic PCR analysis, whereas liver-specific expression of the transgenic human albumin mRNA was validated by RT-PCR analysis. Further immunoblot and mass spectrometry analyses indicated that the transgenic human albumin protein is a full-length, mature protein, which is less abundant than the endogenous mouse albumin that coexists in the serum of the transgenic mouse. The transgenic protein was able to form ex vivo adducts with a genotoxic metabolite of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, a procarcinogenic heterocyclic aromatic amine formed in cooked meat. This novel human albumin transgenic mouse model will facilitate the development and validation of albumin-carcinogen adducts as biomarkers of xenobiotic exposure and/or toxicity in humans. PMID:27028147

  3. LbL Assembly of Albumin on Nitric Oxide-Releasing Silica Nanoparticles Using Suramin, a Polyanion Drug, as an Interlayer Linker.

    PubMed

    Chou, Hung-Chang; Chiu, Shih-Jiuan; Hu, Teh-Min

    2015-08-10

    Preformed protein corona of nanoparticles can be utilized as a promising formulation strategy for improving nano drug delivery. Nitric oxide (NO) is a labile molecule with extensive therapeutic implications. In this study, we test whether preformation of protein coatings can enhance the performance of NO-delivering nanoparticles. S-Nitroso (SNO) silica nanoparticles (SNO-SiNPs) were prepared using a nanoprecipitation method. For the first time, bovine serum albumin (BSA) was used to coat NO-releasing nanoparticles, facilitated by a polyanionic drug, suramin, under a layer-by-layer (LbL) scheme. Bare and coated nanoparticles were characterized by zeta-potential, size, and spectroscopic measurements. We demonstrate that albumin/suramin-surface coassembly has advantages in preventing particle aggregation during lyophilization, controlling NO release and exerting an enhanced anticancer effect. PMID:26121207

  4. Planetary Resources and Astroecology. Planetary Microcosm Models of Asteroid and Meteorite Interiors: Electrolyte Solutions and Microbial Growth- Implications for Space Populations and Panspermia

    NASA Astrophysics Data System (ADS)

    Mautner, Michael N.

    2002-03-01

    Planetary microcosms were constructed using extracts from meteorites that simulate solutions in the pores of carbonaceous chondrites. The microcosms were found to support the growth of complex algal and microbial populations. Such astroecology experiments demonstrate how a diverse ecosystem could exist in fluids within asteroids, and in meteorites that land on aqueous planets. The microcosm solutions were obtained by extracting nutrient electrolytes under natural conditions from powders of the Allende (CV3) and Murchison (CM2) meteorites at low (0.02 g/ml) and high (10.0 g/ml) solid/solution ratios. The latter solutions contain >3 mol/L electrolytes and about 10 g/L organics, that simulate natural fluids in asteroids during aqueous alteration and in the pores of meteorites, which can help prebiotic synthesis and the survival of early microorganisms. These solutions and wet solids were in fact found to support complex self-sustaining microbial communities with populations of 4 × 105 algae and 6 × 106 bacteria and fungi for long periods (>8 months). The results show that planetary microcosms based on meteorites can: assay the fertilities of planetary materials; identify space bioresources; target astrobiology exploration; and model past and future space-based ecosystems. The results show that bioresources in the carbonaceous asteroids can sustain a biomass of 1018 kg, comprising 1032 microorganisms and a human population of 1014. The results also suggest that protoplanetary nebulae can support and disperse microorganisms and can be therefore effective environments for natural and directed panspermia.

  5. The activity-composition relationship of oxygen and hydrogen isotopes in aqueous salt solutions: II. Vapor-liquid water equilibration of mixed salt solutions from 50 to 100°C and geochemical implications

    NASA Astrophysics Data System (ADS)

    Horita, Juske; Cole, David R.; Wesolowski, David J.

    1993-10-01

    The difference between oxygen and hydrogen isotope activity and composition ratios of water in mixed salt solutions in the system Na-K-Mg-Ca-Cl-SO 4-H 2O was determined by means of a vaporliquid water equilibration method over the temperature range of 50 to 100°C. The observed isotope salt effects in complex mixed salt solutions to very high ionic strengths agree quantitatively with calculations based on the assumption of a simple additive property of the isotope salt effects of the individual salts in the solutions. SOFER and GAT (1972, 1975) and HORITA and GAT (1989) also observed that this simple mixing rule applies to synthetic and natural chloride-mixed salt solutions at room temperature. Equations to convert between the isotope activity and composition scales for brines and fractionation factors between brines and other substances are presented. For most geochemical interactions between brines and other phases (vapor, gases, minerals) such as evaporation/boiling, mineral precipitation, and mineral/rock alteration, the isotope activity scale should be used. The isotope composition scale, on the other hand, is most useful for studies of mixing of different brines and formation of brines by mineral dissolution. Misusage of the two isotopic scales of brines will, and probably in the literature has, lead to incorrect conclusions in many isotopic studies of brine-dominated systems (origin of brines, temperature of mineral formation, isotope ratios of fossil fluids).

  6. Implications of Declining Enrolment for the Schools of Ontario. A Statement of Effects and Solutions. Final Report. [Incidences de la Baisse des Effectifs Scolaires sur les Ecoles de l'Ontario. Problemes et Solutions. Rapport Final].

    ERIC Educational Resources Information Center

    Jackson, R. W. B.

    In this final report concerning declining enrollments in Ontario, the problems are defined almost entirely in economic and financial terms, and the solutions expressed in those terms. The first section of the report briefly reviews the essential background, the economic and financial constraints, and finally the demographic facts. The arguments…

  7. Aging-associated oxidized albumin promotes cellular senescence and endothelial damage

    PubMed Central

    Luna, Carlos; Alique, Matilde; Navalmoral, Estefanía; Noci, Maria-Victoria; Bohorquez-Magro, Lourdes; Carracedo, Julia; Ramírez, Rafael

    2016-01-01

    Increased levels of oxidized proteins with aging have been considered a cardiovascular risk factor. However, it is unclear whether oxidized albumin, which is the most abundant serum protein, induces endothelial damage. The results of this study indicated that with aging processes, the levels of oxidized proteins as well as endothelial microparticles release increased, a novel marker of endothelial damage. Among these, oxidized albumin seems to play a principal role. Through in vitro studies, endothelial cells cultured with oxidized albumin exhibited an increment of endothelial damage markers such as adhesion molecules and apoptosis levels. In addition, albumin oxidation increased the amount of endothelial microparticles that were released. Moreover, endothelial cells with increased oxidative stress undergo senescence. In addition, endothelial cells cultured with oxidized albumin shown a reduction in endothelial cell migration measured by wound healing. As a result, we provide the first evidence that oxidized albumin induces endothelial injury which then contributes to the increase of cardiovascular disease in the elderly subjects. PMID:27042026

  8. Influence of Ionic Inorganic Solutes on Self-Assembly and Polymerization Processes Related to Early Forms of Life: Implications for a Prebiotic Aqueous Medium

    NASA Astrophysics Data System (ADS)

    Monnard, Pierre-Alain; Apel, Charles L.; Kanavarioti, Anastassia; Deamer, David W.

    2002-06-01

    A commonly accepted view is that life began in a marine environment, which would imply the presence of inorganic ions such as Na+, Cl-, Mg2+, Ca2+, and Fe2+. We have investigated two processes relevant to the origin of life - membrane self-assembly and RNA polymerization - and established that both are adversely affected by ionic solute concentrations much lower than those of contemporary oceans. In particular, monocarboxylic acid vesicles, which are plausible models of primitive membrane systems, are completely disrupted by low concentrations of divalent cations, such as magnesium and calcium, and by high sodium chloride concentrations as well. Similarly, a nonenzymatic, nontemplated polymerization of activated RNA monomers in ice/eutectic phases (in a solution of low initial ionic strength) yields oligomers with >80% of the original monomers incorporated, but polymerization in initially higher ionic strength aqueous solutions is markedly inhibited. These observations suggest that cellular life may not have begun in a marine environment because the abundance of ionic inorganic solutes would have significantly inhibited the chemical and physical processes that lead to self-assembly of more complex molecular systems.

  9. Fluorescence and Docking Studies of the Interaction between Human Serum Albumin and Pheophytin.

    PubMed

    Chaves, Otávio Augusto; Amorim, Ana Paula de O; Castro, Larissa H E; Sant'Anna, Carlos Mauricio R; de Oliveira, Márcia C C; Cesarin-Sobrinho, Dari; Netto-Ferreira, José Carlos; Ferreira, Aurélio B B

    2015-01-01

    In the North of Brazil (Pará and Amazonas states) the leaves of the plant Talinum triangulare (popular: cariru) replace spinach as food. From a phytochemical point of view, they are rich in compounds of the group of pheophytins. These substances, related to chlorophyll, have photophysical properties that give them potential application in photodynamic therapy. Human serum albumin (HSA) is one of the main endogenous vehicles for biodistribution of molecules by blood plasma. Association constants and thermodynamic parameters for the interaction of HSA with pheophytin from Talinum triangulare were studied by UV-Vis absorption, fluorescence techniques, and molecular modeling (docking). Fluorescence quenching of the HSA's internal fluorophore (tryptophan) at temperatures 296 K, 303 K, and 310 K, resulted in values for the association constants of the order of 10⁴ L∙mol(-1), indicating a moderate interaction between the compound and the albumin. The negative values of ΔG° indicate a spontaneous process; ΔH° = 15.5 kJ∙mol(-1) indicates an endothermic process of association and ΔS° = 0.145 kJ∙mol(-1)∙K(-1) shows that the interaction between HSA and pheophytin occurs mainly by hydrophobic factors. The observed Trp fluorescence quenching is static: there is initial non-fluorescent association, in the ground state, HSA:Pheophytin. Possible solution obtained by a molecular docking study suggests that pheophytin is able to interact with HSA by means of hydrogen bonds with three lysine and one arginine residues, whereas the phytyl group is inserted in a hydrophobic pocket, close to Trp-214. PMID:26516829

  10. Caveolae-Dependent and -Independent Uptake of Albumin in Cultured Rodent Pulmonary Endothelial Cells

    PubMed Central

    Li, Hui-Hua; Li, Jin; Wasserloos, Karla J.; Wallace, Callen; Sullivan, Mara G.; Bauer, Philip M.; Stolz, Donna B.; Lee, Janet S.; Watkins, Simon C.; St Croix, Claudette M.; Pitt, Bruce R.; Zhang, Li-Ming

    2013-01-01

    Although a critical role for caveolae-mediated albumin transcytosis in pulmonary endothelium is well established, considerably less is known about caveolae-independent pathways. In this current study, we confirmed that cultured rat pulmonary microvascular (RPMEC) and pulmonary artery (RPAEC) endothelium endocytosed Alexa488-labeled albumin in a saturable, temperature-sensitive mode and internalization resulted in co-localization by fluorescence microscopy with cholera B toxin and caveolin-1. Although siRNA to caveolin-1 (cav-1) in RPAEC significantly inhibited albumin uptake, a remnant portion of albumin uptake was cav-1-independent, suggesting alternative pathways for albumin uptake. Thus, we isolated and cultured mouse lung endothelial cells (MLEC) from wild type and cav-1-/- mice and noted that ~ 65% of albumin uptake, as determined by confocal imaging or live cell total internal reflectance fluorescence microscopy (TIRF), persisted in total absence of cav-1. Uptake of colloidal gold labeled albumin was evaluated by electron microscopy and demonstrated that albumin uptake in MLEC from cav-1-/- mice was through caveolae-independent pathway(s) including clathrin-coated pits that resulted in endosomal accumulation of albumin. Finally, we noted that albumin uptake in RPMEC was in part sensitive to pharmacological agents (amiloride [sodium transport inhibitor], Gö6976 [protein kinase C inhibitor], and cytochalasin D [inhibitor of actin polymerization]) consistent with a macropinocytosis-like process. The amiloride sensitivity accounting for macropinocytosis also exists in albumin uptake by both wild type and cav-1-/- MLEC. We conclude from these studies that in addition to the well described caveolar-dependent pulmonary endothelial cell endocytosis of albumin, a portion of overall uptake in pulmonary endothelial cells is cav-1 insensitive and appears to involve clathrin-mediated endocytosis and macropinocytosis-like process. PMID:24312378

  11. Importance of albumin in cross-reactivity among cat, dog and horse allergens.

    PubMed

    Cabañas, R; López-Serrano, M C; Carreira, J; Ventas, P; Polo, F; Caballero, M T; Contreras, J; Barranco, P; Moreno-Ancillo, A

    2000-01-01

    Different allergenic proteins have been involved in cross-reactivity among animals. Albumins seem to be cross-sensitizing allergenic components. The aim of this study was to assess the importance of albumin as a cross-reactive allergen in patients sensitized to cat, dog and horse. One hundred and seventeen patients sensitized to cat were tested for IgE reactivity using skin prick tests and RAST assays with cat, dog and horse hair/dander extracts and their purified albumin extracts. RAST-inhibition studies were carried out to assess cross-reactivity among cat, dog and horse and among their purified albumins. It was found that 22% of patients exhibited specific IgE to cat albumin; 41% of patients sensitized to cat were also sensitized to dog and horse. Out of these patients, 21% had IgE to three albumins and 17% to two. Reciprocal inhibitions were observed among cat, dog and horse albumins and also among cat, dog and horse hair/dander extracts, using in the latter experiment sera from patients not sensitized to albumins. IgE binding to horse extract was inhibited 30% by its homologous albumin and IgE binding to cat and dog extracts in almost 15% by their respective albumins. It was concluded that albumins from these three animals share some epitopes that account for the cross-reactivity observed in around one-third of patients sensitized to cat, dog and horse. Nevertheless, more than 50% of specific IgE that cross-reacts among these three animals is directed to allergens other than albumin. PMID:10879993

  12. Preferential interactions of glycine betaine and of urea with DNA: implications for DNA hydration and for effects of these solutes on DNA stability.

    PubMed

    Hong, Jiang; Capp, Michael W; Anderson, Charles F; Saecker, Ruth M; Felitsky, Daniel J; Anderson, Melissa W; Record, M Thomas

    2004-11-23

    Interactions of the solutes glycine betaine (GB) and urea with mononucleosomal calf thymus DNA in aqueous salt solutions are characterized by vapor pressure osmometry (VPO). Analysis of osmolality as a function of solute and DNA concentration yields the effect of the solute on the chemical potential, mu(2), of the DNA. Although both GB and urea generally are nucleic acid denaturants and therefore must interact favorably with the nucleic acid surface exposed upon melting, VPO demonstrates that neither interacts favorably with duplex DNA. Addition of GB greatly increases mu(2) of DNA, indicating that the average local concentration of GB in the vicinity of the double helix is much less than its bulk concentration. By contrast, addition of urea has almost no effect on mu(2) of duplex DNA, indicating that the average local concentration of urea in the vicinity of duplex DNA is almost the same as in bulk solution. Qualitatively, we conclude that the nonuniform distribution of GB occurs primarily because duplex DNA and GB prefer to interact with water rather than with each other. Comparison with thermodynamic data for the interaction of GB with various protein surfaces (Felitsky et al., Biochemistry, 43, 14732-14743) shows that GB is excluded primarily from anionic DNA surface and that the hydration of anionic DNA phosphate oxygen surface (>or approximately 17 H(2)O per nucleotide or >or approximately 0.22 H(2)O A(-)(2)) involves at least two layers of water. From analysis of literature data for effects of urea and of GB on DNA melting, we propose that urea is an effective nonspecific nucleic acid denaturant because of its favorable interactions with the polar amide-like surface of G, C, and especially T or U bases exposed in denaturation, whereas GB is a specific GC denaturant because of its favorable interaction with G and/or C surface in the single-stranded state. PMID:15544345

  13. Planetary resources and astroecology. Planetary microcosm models of asteroid and meteorite interiors: electrolyte solutions and microbial growth--implications for space populations and panspermia.

    PubMed

    Mautner, Michael N

    2002-01-01

    Planetary microcosms were constructed using extracts from meteorites that simulate solutions in the pores of carbonaceous chondrites. The microcosms were found to support the growth of complex algal and microbial populations. Such astroecology experiments demonstrate how a diverse ecosystem could exist in fluids within asteroids, and in meteorites that land on aqueous planets. The microcosm solutions were obtained by extracting nutrient electrolytes under natural conditions from powders of the Allende (CV3) and Murchison (CM2) meteorites at low (0.02 g/ml) and high (10.0 g/ml) solid/solution ratios. The latter solutions contain > 3 mol/L electrolytes and about 10 g/L organics, that simulate natural fluids in asteroids during aqueous alteration and in the pores of meteorites, which can help prebiotic synthesis and the survival of early microorganisms. These solutions and wet solids were in fact found to support complex self-sustaining microbial communities with populations of 4 x 10(5) algae and 6 x 10(6) bacteria and fungi for long periods (> 8 months). The results show that planetary microcosms based on meteorites can: assay the fertilities of planetary materials; identify space bioresources; target astrobiology exploration; and model past and future space-based ecosystems. The results show that bioresources in the carbonaceous asteroids can sustain a biomass of 10(18) kg, comprising 10(32) microorganisms and a human population of 10(14). The results also suggest that protoplanetary nebulae can support and disperse microorganisms and can be therefore effective environments for natural and directed panspermia. PMID:12449855

  14. Effects of Gold Salt Speciation and Structure of Human and Bovine Serum Albumins on the Synthesis and Stability of Gold Nanostructures

    PubMed Central

    Miranda, Érica G. A.; Tofanello, Aryane; Brito, Adrianne M. M.; Lopes, David M.; Albuquerque, Lindomar J. C.; de Castro, Carlos E.; Costa, Fanny N.; Giacomelli, Fernando C.; Ferreira, Fabio F.; Araújo-Chaves, Juliana C.; Nantes, Iseli L.

    2016-01-01

    The present study aimed to investigate the influence of albumin structure and gold speciation on the synthesis of gold nanoparticles (GNPs). The strategy of synthesis was the addition of HAuCl4 solutions at different pH values (3–12) to solutions of human and bovine serum albumins (HSA and BSA) at the same corresponding pH values. Different pH values influence the GNP synthesis due to gold speciation. Besides the inherent effect of pH on the native structure of albumins, the use N-ethylmaleimide (NEM)-treated and heat-denaturated forms of HSA and BSA provided additional insights about the influence of protein structure, net charge, and thiol group approachability on the GNP synthesis. NEM treatment, heating, and the extreme values of pH promoted loss of the native albumin structure. The formation of GNPs indicated by the appearance of surface plasmon resonance (SPR) bands became detectable from 15 days of the synthesis processes that were carried out with native, NEM-treated and heat-denaturated forms of HSA and BSA, exclusively at pH 6 and 7. After 2 months of incubation, SPR band was also detected for all synthesis carried out at pH 8.0. The mean values of the hydrodynamic radius (RH) were 24 and 34 nm for GNPs synthesized with native HSA and BSA, respectively. X-ray diffraction (XRD) revealed crystallites of 13 nm. RH, XRD, and zeta potential values were consistent with GNP capping by the albumins. However, the GNPs produced with NEM-treated and heat-denaturated albumins exhibited loss of protein capping by lowering the ionic strength. This result suggests a significant contribution of non-electrostatic interactions of albumins with the GNP surface, in these conditions. The denaturation of proteins exposes hydrophobic groups to the solvent, and these groups could interact with the gold surface. In these conditions, the thiol blockage or oxidation, the latter probably favored upon heating, impaired the formation of a stable capping by thiol coordination with

  15. Effects of Gold Salt Speciation and Structure of Human and Bovine Serum Albumins on the Synthesis and Stability of Gold Nanostructures.

    PubMed

    Miranda, Érica G A; Tofanello, Aryane; Brito, Adrianne M M; Lopes, David M; Albuquerque, Lindomar J C; de Castro, Carlos E; Costa, Fanny N; Giacomelli, Fernando C; Ferreira, Fabio F; Araújo-Chaves, Juliana C; Nantes, Iseli L

    2016-01-01

    The present study aimed to investigate the influence of albumin structure and gold speciation on the synthesis of gold nanoparticles (GNPs). The strategy of synthesis was the addition of HAuCl4 solutions at different pH values (3-12) to solutions of human and bovine serum albumins (HSA and BSA) at the same corresponding pH values. Different pH values influence the GNP synthesis due to gold speciation. Besides the inherent effect of pH on the native structure of albumins, the use N-ethylmaleimide (NEM)-treated and heat-denaturated forms of HSA and BSA provided additional insights about the influence of protein structure, net charge, and thiol group approachability on the GNP synthesis. NEM treatment, heating, and the extreme values of pH promoted loss of the native albumin structure. The formation of GNPs indicated by the appearance of surface plasmon resonance (SPR) bands became detectable from 15 days of the synthesis processes that were carried out with native, NEM-treated and heat-denaturated forms of HSA and BSA, exclusively at pH 6 and 7. After 2 months of incubation, SPR band was also detected for all synthesis carried out at pH 8.0. The mean values of the hydrodynamic radius (RH) were 24 and 34 nm for GNPs synthesized with native HSA and BSA, respectively. X-ray diffraction (XRD) revealed crystallites of 13 nm. RH, XRD, and zeta potential values were consistent with GNP capping by the albumins. However, the GNPs produced with NEM-treated and heat-denaturated albumins exhibited loss of protein capping by lowering the ionic strength. This result suggests a significant contribution of non-electrostatic interactions of albumins with the GNP surface, in these conditions. The denaturation of proteins exposes hydrophobic groups to the solvent, and these groups could interact with the gold surface. In these conditions, the thiol blockage or oxidation, the latter probably favored upon heating, impaired the formation of a stable capping by thiol coordination with the

  16. Recognition of oxidized albumin and thyroid antigens by psoriasis autoantibodies

    PubMed Central

    Al-Shobaili, Hani A.; Ahmed, Ahmed A.; Rasheed, Zafar

    2015-01-01

    Objectives: To investigate the role of reactive-oxygen-species (ROS) induced epitopes on human-serum-albumin (HSA) and thyroid antigens in psoriasis autoimmunity. Methods: This study was performed in the College of Medicine, Qassim University, Buraidah, Saudi Arabia between May 2014 and February 2015. The study was designed to explore the role of ROS-induced epitopes in psoriasis autoimmunity. Singlet-oxygen (or ROS)-induced epitopes on protein (ROS-epitopes-albumin) was characterized by in-vitro and in-vivo. Thyroid antigens were prepared from rabbit thyroid, and thyroglobulin was isolated from thyroid extract. Immunocross-reactions of protein-A purified anti-ROS-epitopes-HSA-immunoglobulin G (IgGs) with thyroid antigen, thyroglobulin, and their oxidized forms were determined. Binding characteristics of autoantibodies in chronic plaque psoriasis patients (n=26) against ROS-epitopes-HSA and also with native and oxidized thyroid antigens were screened, and the results were compared with age-matched controls (n=22). Results: The anti-ROS-epitopes-HSA-IgGs showed cross-reactions with thyroid antigen, thyroglobulin and with their oxidized forms. High degree of specific binding by psoriasis IgGs to ROS-epitopes-HSA, ROS-thyroid antigen and ROS-thyroglobulin was observed. Immunoglobulin G from normal-human-controls showed negligible binding with all tested antigens. Moreover, sera from psoriasis patients had higher levels of carbonyl contents compared with control sera. Conclusion: Structural alterations in albumin, thyroid antigens by ROS, generate unique neo-epitopes that might be one of the factors for the induction of autoantibodies in psoriasis. PMID:26620982

  17. Tumor necrosis factor-alpha inhibits albumin gene expression in a murine model of cachexia.

    PubMed Central

    Brenner, D A; Buck, M; Feitelberg, S P; Chojkier, M

    1990-01-01

    The mechanisms responsible for decreased serum albumin levels in patients with cachexia-associated infection, inflammation, and cancer are unknown. Since tumor necrosis factor-alpha (TNF alpha) is elevated in cachexia-associated diseases, and chronic administration of TNF alpha induces cachexia in animal models, we assessed the regulation of albumin gene expression by TNF alpha in vivo. In this animal model of cachexia, Chinese hamster ovary cells transfected with the functional gene for human TNF alpha were inoculated into nude mice (TNF alpha mice). TNF alpha mice became cachectic and manifested decreased serum albumin levels, albumin synthesis, and albumin mRNA levels. However, even before the TNF alpha mice lost weight, their albumin mRNA steady-state levels were decreased approximately 90%, and in situ hybridization revealed a low level of albumin gene expression throughout the hepatic lobule. The mRNA levels of several other genes were unchanged. Hepatic nuclei from TNF alpha mice before the onset of weight loss were markedly less active in transcribing the albumin gene than hepatic nuclei from control mice. Therefore, TNF alpha selectively inhibits the genetic expression of albumin in this model before weight loss. Images PMID:2295699

  18. A retrospective analysis of 25% human serum albumin supplementation in hypoalbuminemic dogs with septic peritonitis

    PubMed Central

    Horowitz, Farrah B.; Read, Robyn L.; Powell, Lisa L.

    2015-01-01

    This study describes the influence of 25% human serum albumin (HSA) supplementation on serum albumin level, total protein (TP), colloid osmotic pressure (COP), hospital stay, and survival in dogs with septic peritonitis. Records of 39 dogs with septic peritonitis were evaluated. In the HSA group, initial and post-transfusion TP, albumin, COP, and HSA dose were recorded. In the non-supplemented group, repeated values of TP, albumin, and COP were recorded over their hospitalization. Eighteen dogs survived (53.8% mortality). Repeat albumin values were higher in survivors (mean 23.9 g/L) and elevated repeat albumin values were associated with HSA supplementation. Repeat albumin and TP were higher in the HSA supplemented group (mean 24 g/L and 51.9 g/L, respectively) and their COP increased by 5.8 mmHg. Length of hospitalization was not affected. Twenty-five percent HSA increases albumin, TP, and COP in canine patients with septic peritonitis. Higher postoperative albumin levels are associated with survival. PMID:26028681

  19. Review: modifications of human serum albumin and their binding effect.

    PubMed

    Lee, Philbert; Wu, Xiaoyang

    2015-01-01

    Human serum albumin (HSA) regulates the transport and availability of numerous chemical compounds and molecules in the blood vascular system. While previous HSA research has found that HSA interacts with specific varieties of ligands, new research efforts aim to expand HSA's ability to interact with more different drugs in order to improve the delivery of various pharmacological drugs. This review will cover fatty acid chain and posttranslational modifications of HSA that potentially modulate how HSA interacts with various pharmacological drugs, including glycation, cysteinylation, S-nitrosylation, S-transnitrosation and S-guanylation. PMID:25732553

  20. Highly sensitive bovine serum albumin biosensor based on liquid crystal

    NASA Astrophysics Data System (ADS)

    Sharma, Vikash; Kumar, Ajay; Ganguly, Prasun; Biradar, A. M.

    2014-01-01

    A highly sensitive liquid crystal (LC) based bovine serum albumin (BSA) protein biosensor is designed. A uniform homeotropic alignment of nematic LC was observed in BSA free substrate which changed into homogeneous in presence of BSA. The change in the LC orientation is found to depend strongly on BSA concentration. This change in the LC alignment is attributed to the modification in the surface conditions which is verified by contact angle measurements. We have detected an ultra low concentration (0.5 μg/ml) of BSA. The present study demonstrates the utilization of LC in the realization of high sensitivity biosensors.

  1. Review: Modifications of Human Serum Albumin and Their Binding Effect

    PubMed Central

    Lee, Philbert; Wu, Xiaoyang

    2015-01-01

    Human serum albumin (HSA) regulates the transport and availability of numerous chemical compounds and molecules in the blood vascular system. While previous HSA research has found that HSA interacts with specific varieties of ligands, new research efforts aim to expand HSA’s ability to interact with more different drugs in order to improve the delivery of various pharmacological drugs. This review will cover fatty acid chain and post-translational modifications of HSA that potentially modulate how HSA interacts with various pharmacological drugs, including glycation, cysteinylation, S-nitrosylation, S-transnitrosation and S-guanylation. PMID:25732553

  2. In Vivo Labeling of Serum Albumin for PET

    PubMed Central

    Niu, Gang; Lang, Lixin; Kiesewetter, Dale O.; Ma, Ying; Sun, Zhongchan; Guo, Ning; Guo, Jinxia; Wu, Chenxi; Chen, Xiaoyuan

    2015-01-01

    The purpose of this study was to develop a novel in vivo albumin-labeling method to allow PET of cardiac function after myocardial infarction and vascular leakage and increased permeability in inflammatory diseases and malignant tumors. Methods To label albumin in vivo, we synthesized a NOTA (1,4,7-triazacyclononane-N,N′, N″-triacetic acid)-conjugated truncated form of Evans blue (NEB). 18F labeling was achieved by the formation of an 18F-aluminum fluoride (18F-AlF) complex, and 64Cu labeling was obtained by a standard chelation method. Sixty-minute dynamic PET imaging was performed on normal mice to evaluate the distribution of 18F-AlF-NEB, which was compared with in vitro–labeled mouse serum albumin (18F-fluorobenzyl-MSA). Electrocardiography-gated PET imaging was performed in a mouse model of myocardial infarction. Both dynamic and static PET scans were obtained in a mouse inflammation model induced by local injection of turpentine to evaluate vascular leakage. Tumor permeability was studied by dynamic and late-point static PET using 64Cu-NEB in a UM-22B xenograft model. Results NEB was successfully synthesized, and 18F labeling including work-up took about 20–30 min, with a radiochemical purity greater than 95% without the need for high-performance liquid chromatography purification. Most of the radioactivity was retained in the circulation system at 60 min after injection (26.35 ± 1.52 percentage injected dose per gram [%ID/g]). With electrocardiography-gated PET, ventricles of the heart and major arteries were clearly visualized. The myocardial infarction mice showed much lower left ventricular ejection fraction than the control mice. Inflammatory muscles showed significantly higher tracer accumulation than the contralateral healthy ones. UM-22B tumor uptake of 64Cu-NEB gradually increased with time (5.73 ± 1.11 %ID/g at 1 h and 8.03 ± 0.77 %ID/g at 2 h after injection). Conclusion The distribution and local accumulation of serum albumin can be

  3. Sequences Of Amino Acids For Human Serum Albumin

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.

    1992-01-01

    Sequences of amino acids defined for use in making polypeptides one-third to one-sixth as large as parent human serum albumin molecule. Smaller, chemically stable peptides have diverse applications including service as artificial human serum and as active components of biosensors and chromatographic matrices. In applications involving production of artificial sera from new sequences, little or no concern about viral contaminants. Smaller genetically engineered polypeptides more easily expressed and produced in large quantities, making commercial isolation and production more feasible and profitable.

  4. Particle reduction of a macroaggregated albumin kit: Simplified calculations

    SciTech Connect

    Levine, E.K.; Perritt, J.S.; Gordon, L. )

    1989-09-01

    It is often difficult to compare a dose of technetium-99m ({sup 99m}Tc) macroaggregated albumin, which contains both a specified number of particles, as well as a specific dose in millicuries. This is further complicated by the fact that the commercial kit used contains many times more particles than is needed, particularly in the pediatric patient population. The authors have developed a set of simple formulas to facilitate calculating the number of millicuries and volume of sodium pertechnetate ({sup 99m}Tc) to be added to the kit.

  5. Albumin-based nanoparticle trehalose lyophilisation stress-down to preserve structure/function and enhanced binding.

    PubMed

    Siri, Macarena; Grasselli, Mariano; Alonso, Silvia Del V

    2016-07-15

    The aim of this study was to preserve albumin nanoparticle structure/function during the lyophilisation process. Bovine serum albumin nanoparticles were obtained by γ-irradiation. Nanoparticles were lyophilised in buffer, miliQ water or in trehalose/miliQ solution. The size and charge of the nanoparticles were tested after lyophilisation by light scattering and Z potential. The most relevant results in size of BSA nanoparticle were those lyophilised in PBS between 20 and 350nm, assembled in different aggregates, and negative Z potential obtained was 37±8mV in all, and those nanoparticles lyophilised with trehalose had a size range of 70±2nm and a negative Z potential of 20±5mV. Structure determination of surface aminoacids SH groups in the BSA NP lyophilised in PBS showed an increase in the free SH groups. Different aggregates had different amount of SH groups exposure from 55 to 938 (from smaller to bigger aggregates), whereas BSA NP lyophilised with trehalose showed no significant difference if compared with BSA NP. The binding properties of the BSA nanoparticle with a theragnostic probe (merocyanine 540) were studied after lyophilisation. Results showed more affinity between the BSA NP lyophilised with trehalose than that observed with non lyophilised BSA NP. As a result, the lyophilisation condition in trehalose 100μM solution is the best one to preserve the BSA NP structure/function and the one with the enhance binding affinity of the BSA NP. PMID:27174378

  6. Slow continuous ultrafiltration with bound solute dialysis.

    PubMed

    Patzer, John F; Safta, Stefan A; Miller, Richard H

    2006-01-01

    Bound solute dialysis (BSD), often referred to as "albumin dialysis" (practiced clinically as the molecular adsorbents recirculating system, MARS, or single-pass albumin dialysis, SPAD) or "sorbent dialysis" (practiced clinically as the charcoal-based Biologic-DT), is based upon the thermodynamic principle that the driving force for solute mass transfer across a dialysis membrane is the difference in free solute concentration across the membrane. The clinically relevant practice of slow continuous ultrafiltration (SCUF) for maintenance of patients with liver failure is analyzed in conjunction with BSD. The primary dimensionless operating parameters that describe SCUF-BSD include (1) beta, the dialysate/blood binder concentration ratio; (2) kappa, the dialyzer mass transfer/blood flow rate ratio; (3) alpha, the dialysate/blood flow rate ratio; and, (4) gamma, the ultrafiltration/blood flow rate ratio. Results from mathematical modeling of solute removal during a single pass through a dialyzer and solute removal from a one-compartment model indicate that solute removal is remarkably insensitive to gamma. Solute removal approaches an asymptote (improvement in theoretical clearance over that obtainable with no binder in the dialysate) with increasing beta that is dependent on kappa and independent of alpha. The amount of binder required to approach the asymptote decreases with increasing solute-binder equilibrium constant, i.e., more strongly bound solutes require less binder in the dialysate. The results of experimental observations over a range of blood flow rates, 100 to 180 mL/min, dialysate flow rates, 600 to 2150 mL/h, ultrafiltration rates, 0 to 220 mL/h, and dialysate/blood albumin concentration ratios, beta = 0.01 to 0.04, were independently predicted remarkably well by the one-compartment model (with no adjustable parameters) based on BSD principles. PMID:16436890

  7. The solution configurations of inactive and activated DntR have implications for the sliding dimer mechanism of LysR transcription factors

    PubMed Central

    Lerche, Michael; Dian, Cyril; Round, Adam; Lönneborg, Rosa; Brzezinski, Peter; Leonard, Gordon A.

    2016-01-01

    LysR Type Transcriptional Regulators (LTTRs) regulate basic metabolic pathways or virulence gene expression in prokaryotes. Evidence suggests that the activation of LTTRs involves a conformational change from an inactive compact apo- configuration that represses transcription to an active, expanded holo- form that promotes it. However, no LTTR has yet been observed to adopt both configurations. Here, we report the results of structural studies of various forms of the LTTR DntR. Crystal structures of apo-DntR and of a partially autoinducing mutant H169T-DntR suggest that active and inactive DntR maintain a compact homotetrameric configuration. However, Small Angle X-ray Scattering (SAXS) studies on solutions of apo-, H169T- and inducer-bound holo-DntR indicate a different behaviour, suggesting that while apo-DntR maintains a compact configuration in solution both H169T- and holo-DntR adopt an expanded conformation. Models of the SAXS-obtained solution conformations of apo- and holo-DntR homotetramers in complex with promoter-operator region DNA are consistent with previous observations of a shifting of LTTR DNA binding sites upon activation and a consequent relaxation in the bend of the promoter-operator region DNA. Our results thus provide clear evidence at the molecular level which strongly supports the ‘sliding dimer’ hypothesis concerning LTTR activation mechanisms. PMID:26817994

  8. The solution structures of native and patient monomeric human IgA1 reveal asymmetric extended structures: implications for function and IgAN disease

    PubMed Central

    Hui, Gar Kay; Wright, David W.; Vennard, Owen L.; Rayner, Lucy E.; Pang, Melisa; Yeo, See Cheng; Gor, Jayesh; Molyneux, Karen; Barratt, Jonathan; Perkins, Stephen J.

    2015-01-01

    Native IgA1, for which no crystal structure is known, contains an O-galactosylated 23-residue hinge region that joins its Fab and Fc regions. IgA nephropathy (IgAN) is a leading cause of chronic kidney disease in developed countries. Because IgA1 in IgAN often has a poorly O-galactosylated hinge region, the solution structures of monomeric IgA1 from a healthy subject and three IgAN patients with four different O-galactosylation levels were studied. Analytical ultracentrifugation showed that all four IgA1 samples were monomeric with similar sedimentation coefficients, s020,w. X-ray scattering showed that the radius of gyration (Rg) slightly increased with IgA1 concentration, indicating self-association, although their distance distribution curves, P(r), were unchanged with concentration. Neutron scattering indicated similar Rg values and P(r) curves, although IgA1 showed a propensity to aggregate in heavy water buffer. A new atomistic modelling procedure based on comparisons with 177000 conformationally-randomized IgA1 structures with the individual experimental scattering curves revealed similar extended Y-shaped solution structures for all four differentially-glycosylated IgA1 molecules. The final models indicated that the N-glycans at Asn263 were folded back against the Fc surface, the C-terminal tailpiece conformations were undefined and hinge O-galactosylation had little effect on the solution structure. The solution structures for full-length IgA1 showed extended hinges and the Fab and Fc regions were positioned asymmetrically to provide ample space for the functionally-important binding of two FcαR receptors to its Fc region. Whereas no link between O-galactosylation and the IgA1 solution structure was detected, an increase in IgA1 aggregation with reduced O-galactosylation may relate to IgAN. PMID:26268558

  9. Fructosylation generates neo-epitopes on human serum albumin.

    PubMed

    Allarakha, Shaziya; Ahmad, Parvez; Ishtikhar, Mohd; Zaheer, Mohammad Shoaib; Siddiqi, Sheelu Shafiq; Moinuddin; Ali, Asif

    2015-05-01

    Hyperglycemia is the defining feature of diabetes mellitus. The persistently high levels of reducing sugars like glucose and fructose cause glycation of various macromolecules in the body. Human serum albumin (HSA), the most abundant serum protein with a myriad of functions, is prone to glycation and consequent alteration in its structural and biological properties. This study aimed to assess the role of fructose-modified human serum albumin as a marker of diabetic pathophysiology. We carried out modification of HSA with fructose and the changes induced were studied by various physicochemical studies. Fructose modified-HSA showed hyperchromicity in UV spectrum and increased AGE-specific fluorescence as well as quenching of tryptophan fluorescence. In SDS-PAGE protein aggregation was seen. Amadori products were detected by NBT. The fructose modified HSA had higher content of carbonyls along with perturbations in secondary structure as revealed by CD and FT-IR. A greater hydrodynamic radius of fructose-modified HSA was evident by DLS measurement. The fructose-modified HSA induced high titre antibodies in experimental animals exhibiting high specificity towards the immunogen. PMID:25914162

  10. Endocytosis and transcytosis of albumin gold through mice peritoneal mesothelium.

    PubMed

    Gotloib, L; Shostak, A

    1995-05-01

    The present transmission electron microscopy (TEM) study was designed to investigate whether mesothelial cells of mice diaphragmatic, parietal and mesenteric peritoneum are actively coupled to the mechanisms involved in the transerosal absorption of albumin gold complexes (Alb-Au). Five albino mice were injected intraperitoneally with 0.5 ml of a suspension of Alb-Au. In three animals, in vivo fixation was done 10 minutes after injection of Alb-Au, whereas in the remaining two, fixation was performed 45 minutes after injection of the tracer. At both time intervals, a substantial part of Alb-Au complexes was observed within plasmalemmal and coated vesicles, mainly attached to the luminal aspect of the internal luminal membranes. The amount of Alb-Au contained in plasmalemmal vesicles was significantly higher than that detected in intermesothelial junctions. Plasmalemmal vesicles were observed discharging Alb-Au complexes in the submesothelial interstitium, showing a significantly higher proportion of the tracer associated with non-junctional areas. Evidence presented in this study supports the idea of local degradation of Alb-Au in mesothelial cells after endocytosis, and that of a continuously transcytotic mechanism transporting polymerized albumin across the mesothelial layer. In this sense, transcytotic vesicles could represent the large pore equivalent. PMID:7637257

  11. Hepatic functional scintigraphic imaging with 99mtechnetium galactosyl serum albumin.

    PubMed

    Kubota, Y; Kitagawa, S; Inoue, K; Ha-Kawa, S K; Kojima, M; Tanaka, Y

    1993-02-01

    99mTc-galactosyl serum albumin (GSA), a specific radiolabeled synthetic ligand for asialoglycoprotein receptors on hepatocytes, was used for functional liver imaging in 18 patients. Six patients had chronic hepatitis, and 12 had liver cirrhosis. Serial scintigraphic images were obtained for 60 minutes after intravenous administration of 1 mg of the ligand. High-quality images of the liver was obtained in all the patients. Dispersed accumulation in the liver in association with delayed clearance of the ligand from the heart was noted in cirrhotic patients. The activity of the entire liver (L) and that of the heart (H) were measured. The capacity of the liver in terms of elimination of the ligand was estimated by calculating [L/H+L] 15 and 30 minutes after the administration. [L/H+L] showed significant differences between patients with chronic hepatitis and those with liver cirrhosis, and also showed significant correlations with laboratory values such as indocyanine green clearance, prothrombin time, hepaplastin test, serum albumin level, and the Child-Turcotte classification score. 99mTc-GSA might be a useful radiopharmaceutical for obtaining hepatic functional images. PMID:8462925

  12. Albumin-associated free fatty acids induce macropinocytosis in podocytes

    PubMed Central

    Chung, Jun-Jae; Huber, Tobias B.; Gödel, Markus; Jarad, George; Hartleben, Björn; Kwoh, Christopher; Keil, Alexander; Karpitskiy, Aleksey; Hu, Jiancheng; Huh, Christine J.; Cella, Marina; Gross, Richard W.; Miner, Jeffrey H.; Shaw, Andrey S.

    2015-01-01

    Podocytes are specialized epithelial cells in the kidney glomerulus that play important structural and functional roles in maintaining the filtration barrier. Nephrotic syndrome results from a breakdown of the kidney filtration barrier and is associated with proteinuria, hyperlipidemia, and edema. Additionally, podocytes undergo changes in morphology and internalize plasma proteins in response to this disorder. Here, we used fluid-phase tracers in murine models and determined that podocytes actively internalize fluid from the plasma and that the rate of internalization is increased when the filtration barrier is disrupted. In cultured podocytes, the presence of free fatty acids (FFAs) associated with serum albumin stimulated macropinocytosis through a pathway that involves FFA receptors, the Gβ/Gγ complex, and RAC1. Moreover, mice with elevated levels of plasma FFAs as the result of a high-fat diet were more susceptible to Adriamycin-induced proteinuria than were animals on standard chow. Together, these results support a model in which podocytes sense the disruption of the filtration barrier via FFAs bound to albumin and respond by enhancing fluid-phase uptake. The response to FFAs may function in the development of nephrotic syndrome by amplifying the effects of proteinuria. PMID:25915582

  13. Antibacterial releasing titanium surface using albumin nanoparticle carriers.

    PubMed

    Kim, Da Hye; Kim, Kyo-Han; Kwon, Tae-Yub; Choi, Seok Hwa; Kang, Seong Soo; Kwon, Soon-Taek; Cho, Dae-Hyun; Kim, Hee Dong; Son, Jun Sik

    2014-11-01

    We developed a simple and highly efficient method for delivery from titanium (Ti) surfaces using albumin nanoparticle carriers. A Ti disc with a resorbable blasting media surface was used as a metal implant with a localized drug delivery structure. Human serum albumin (HSA) nanoparticles loaded with chlorhexidine (CHX) diacetate salt hydrate as the model drug were fabricated using a desolvation technique. The CHX-loaded HSA nanoparticles produced were cross linked with glutaraldehyde (GA). The nanoparticles were pre-coated with positively-charged polyethylenimine (PEI) molecules and then immobilized via electrical interactions on the negatively charged Ti disc surface. Our results suggested that the PEI-coated HSA nanoparticles loaded with CHX (PEI-CHX-HSA) were incorporated successfully and well-dispersed on the Ti disc surfaces. The agar diffusion test on the Ti surface treated with PEI-CHX-HSA nanoparticles showed a larger growth inhibition zone of Streptococcus mutans versus the control Ti surface, suggesting that this innovative delivery platform imparts potent antibacterial activity to the Ti surface. Thus, CHX, which inhibits the growth of oral bacteria, can be efficiently incorporated onto Ti surfaces by using HSA nanoparticles. PMID:25958539

  14. Potentiometric responses of ion-selective microelectrode with bovine serum albumin adsorption.

    PubMed

    Goda, Tatsuro; Yamada, Eriko; Katayama, Yurika; Tabata, Miyuki; Matsumoto, Akira; Miyahara, Yuji

    2016-03-15

    There is a growing demand for an in situ measurement of local pH and ion concentrations in biological milieu to monitor ongoing process of bioreaction and bioresponse in real time. An ion-selective microelectrode can meet the requirements. However, the contact of the electrode with biological fluids induces biofouling by protein adsorption to result in a noise signal. Therefore, we investigated the relationship between the amount of nonspecific protein adsorption and the electrical signals in potentiometry by using ion-selective microelectrodes, namely silver/silver chloride (Ag/AgCl), iridium/iridium oxides (Ir/IrOx), and platinum/iridium oxides (Pt/IrOx). The microelectrodes reduced a potential change following the adsorption of bovine serum albumin (BSA) by comparison with the original metal microelectrodes without oxide layers. Suppression in the noise signal was attributed to the increased capacitance at the electrode/solution interface due to the formation of granulated metal oxide layer rather than a decrease in the amount of protein adsorbed. Ion sensitivity was maintained for Ir/IrOx against proton, but it was not for Ag/AgCl against chloride ion (Cl(-)), because of the interference of the equilibrium reaction by adsorbed BSA molecules on the electrode surface at<10(-2)M [Cl(-)] in the solution. The results open up the application of the Ir/IrOx microelectrode for measuring local pH in realistic dirty samples with a limited influence of electrode pollution by protein adsorption. PMID:26409020

  15. Detecting trypsin at liquid crystal/aqueous interface by using surface-immobilized bovine serum albumin.

    PubMed

    Chuang, Cheng-Hao; Lin, Yi-Cheng; Chen, Wei-Long; Chen, Yu-Hsuan; Chen, Yu-Xun; Chen, Chieh-Ming; Shiu, Hung Wei; Chang, Lo-Yueh; Chen, Chia-Hao; Chen, Chih-Hsin

    2016-04-15

    We report a new mechanism for liquid crystal (LC)-based sensor system for trypsin detection. In this system, bovine serum albumin (BSA) was immobilized on gold grids as the enzymatic substrate. When the BSA-modified grid was filled with LC and immersed in the solution containing trypsin, the peptide bonds of BSA were hydrolyzed and peptide fragments were desorbed from the surface of gold grid, which disrupted the orientation of LC at the vicinity and resulted in a dark-to-bright transition of optical image of LCs. By using this mechanism, the limit of detection (LOD) of trypsin is 10 ng/mL, and it does not respond to thrombin and pepsin. Besides, the cleavage behavior on gold surfaces was directly visualized by the scanning photoelectron microscopy (SPEM), in particular for the chemical composition identification and element-resolved image. The loss of BSA fragments and the enhancement of Au photoelectron signal after trypsin cleavage were corresponding to the proposed mechanism of the LC-based sensor system. Because the signals reported by LC can be simply interpreted through the human naked-eye, it provides a simple method for fast-screening trypsin activity in aqueous solution. PMID:26613511

  16. A simple improved desolvation method for the rapid preparation of albumin nanoparticles.

    PubMed

    Jahanban-Esfahlan, Ali; Dastmalchi, Siavoush; Davaran, Soodabeh

    2016-10-01

    The current study tried to establish a simple and fast method for the preparation of BSA and HSA nanoparticles, based on an improved desolvation procedure under the aspect of a controllable particle size around 100nm for drug delivery applications. The Procedure used for the nanoparticles preparation was simplified by using a designed apparatus for controlling the addition of ethanol and it was used instead of conventional tubing pump which enabled the preparation of nanoparticles under defined conditions. By using EDC as cross-linker instead of glutharaldehyde, the time of nanoparticles preparation procedure was reduced to 3h. Several factors of the preparation process, such as the volume of the albumin solution, desolvating agent volume, the amount of cross-linker, the presence of salts and protein concentration were evaluated. Nanoparticles with smaller size were obtained under experimental conditions without the presence of salts or the use of buffers, 250mg of protein/4ml water, 5mg cross-linker, the addition of 4 and 8ml ethanol by using the designed apparatus to the HSA and BSA solution, respectively. By using this improved method, BSA and HSA nanoparticles of the size around 100nm and polydispersity below 0.2 were obtained. PMID:27177461

  17. Comparative binding character of two general anaesthetics for sites on human serum albumin.

    PubMed Central

    Liu, Renyu; Meng, Qingcheng; Xi, Jin; Yang, Jinsheng; Ha, Chung-Eun; Bhagavan, Nadhipuram V; Eckenhoff, Roderic G

    2004-01-01

    Propofol and halothane are clinically used general anaesthetics, which are transported primarily by HSA (human serum albumin) in the blood. Binding characteristics are therefore of interest for both the pharmacokinetics and pharmacodynamics of these drugs. We characterized anaesthetic-HSA interactions in solution using elution chromatography, ITC (isothermal titration calorimetry), hydrogen-exchange experiments and geometric analyses of high-resolution structures. Binding affinity of propofol to HSA was determined to have a K(d) of 65 microM and a stoichiometry of approx. 2, whereas the binding of halothane to HSA showed a K(d) of 1.6 mM and a stoichiometry of approx. 7. Anaesthetic-HSA interactions are exothermic, with propofol having a larger negative enthalpy change relative to halothane. Hydrogen-exchange studies in isolated recombinant domains of HSA showed that propofol-binding sites are primarily found in domain III, whereas halothane sites are more widely distributed. Both location and stoichiometry from these solution studies agree with data derived from X-ray crystal-structure studies, and further analyses of the architecture of sites from these structures suggested that greater hydrophobic contacts, van der Waals interactions and hydrogen-bond formation account for the stronger binding of propofol as compared with the less potent anaesthetic, halothane. PMID:14759223

  18. Spread Films of Human Serum Albumin at the Air-Water Interface: Optimization, Morphology, and Durability.

    PubMed

    Campbell, Richard A; Ang, Joo Chuan; Sebastiani, Federica; Tummino, Andrea; White, John W

    2015-12-22

    It has been known for almost one hundred years that a lower surface tension can be achieved at the air-water interface by spreading protein from a concentrated solution than by adsorption from an equivalent total bulk concentration. Nevertheless, the factors that control this nonequilibrium process have not been fully understood. In the present work, we apply ellipsometry, neutron reflectometry, X-ray reflectometry, and Brewster angle microscopy to elaborate the surface loading of human serum albumin in terms of both the macroscopic film morphology and the spreading dynamics. We show that the dominant contribution to the surface loading mechanism is the Marangoni spreading of protein from the bulk of the droplets rather than the direct transfer of their surface films. The films can be spread on a dilute subphase if the concentration of the spreading solution is sufficient; if not, dissolution of the protein occurs, and only a textured adsorbed layer slowly forms. The morphology of the spread protein films comprises an extended network with regions of less textured material or gaps. Further, mechanical cycling of the surface area of the spread films anneals the network into a membrane that approach constant compressibility and has increased durability. Our work provides a new perspective on an old problem in colloid and interface science. The scope for optimization of the surface loading mechanism in a range of systems leading to its exploitation in deposition-based technologies in the future is discussed. PMID:26607026

  19. Thrombin stimulates albumin transcytosis in lung microvascular endothelial cells via activation of acid sphingomyelinase.

    PubMed

    Kuebler, Wolfgang M; Wittenberg, Claudia; Lee, Warren L; Reppien, Eike; Goldenberg, Neil M; Lindner, Karsten; Gao, Yizhuo; Winoto-Morbach, Supandi; Drab, Marek; Mühlfeld, Christian; Dombrowsky, Heike; Ochs, Matthias; Schütze, Stefan; Uhlig, Stefan

    2016-04-15

    Transcellular albumin transport occurs via caveolae that are abundant in lung microvascular endothelial cells. Stimulation of albumin transcytosis by proinflammatory mediators may contribute to alveolar protein leak in lung injury, yet the regulation of albumin transport and its underlying molecular mechanisms are so far incompletely understood. Here we tested the hypothesis that thrombin may stimulate transcellular albumin transport across lung microvascular endothelial cells in an acid-sphingomyelinase dependent manner. Thrombin increased the transport of fluorescently labeled albumin across confluent human lung microvascular endothelial cell (HMVEC-L) monolayers to an extent that markedly exceeds the rate of passive diffusion. Thrombin activated acid sphingomyelinase (ASM) and increased ceramide production in HMVEC-L, but not in bovine pulmonary artery cells, which showed little albumin transport in response to thrombin. Thrombin increased total caveolin-1 (cav-1) content in both whole cell lysates and lipid rafts from HMVEC-L, and this effect was blocked by inhibition of ASM or de novo protein biosynthesis. Thrombin-induced uptake of albumin into lung microvascular endothelial cells was confirmed in isolated-perfused lungs by real-time fluorescence imaging and electron microscopy of gold-labeled albumin. Inhibition of ASM attenuated thrombin-induced albumin transport both in confluent HMVEC-L and in intact lungs, whereas HMVEC-L treatment with exogenous ASM increased albumin transport and enriched lipid rafts in cav-1. Our findings indicate that thrombin stimulates transcellular albumin transport in an acid sphingomyelinase-dependent manner by inducing de novo synthesis of cav-1 and its recruitment to membrane lipid rafts. PMID:26851257

  20. Capturing Labile Sulfenamide and Sulfinamide Serum Albumin Adducts of Carcinogenic Arylamines by Chemical Oxidation

    PubMed Central

    Peng, Lijuan; Turesky, Robert J.

    2013-01-01

    Aromatic amines and heterocyclic aromatic amines (HAAs) are a class of structurally related carcinogens that are formed during the combustion of tobacco or during the high temperature cooking of meats. These procarcinogens undergo metabolic activation by N-oxidation of the exocyclic amine group to produce N-hydroxylated metabolites, which are critical intermediates implicated in toxicity and DNA damage. The arylhydroxylamines and their oxidized arylnitroso derivatives can also react with cysteine (Cys) residues of glutathione or proteins to form, respectively, sulfenamide and sulfinamide adducts. However, sulfur-nitrogen linked adducted proteins are often difficult to detect because they are unstable and undergo hydrolysis during proteolytic digestion. Synthetic N-oxidized intermediates of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a carcinogenic HAA produced in cooked meats, and 4-aminobiphenyl, a carcinogenic aromatic amine present in tobacco smoke were reacted with human serum albumin (SA) and formed labile sulfenamide or sulfinamide adducts at the Cys34 residue. Oxidation of the carcinogen-modified SA with m-chloroperoxybenzoic acid (m-CPBA) produced the arylsulfonamide adducts, which were stable to heat and the chemical reduction conditions employed to denature SA. The sulfonamide adducts of PhIP and 4-ABP were identified, by liquid chromatography/mass spectrometry, in proteolytic digests of denatured SA. Thus, selective oxidation of arylamine-modified SA produces stable arylsulfonamide-SA adducts, which may serve as biomarkers of these tobacco and dietary carcinogens. PMID:23240913

  1. Solute and particle retention in the digestive tract of the Phillip's dikdik (Madoqua saltiana phillipsi), a very small browsing ruminant: biological and methodological implications.

    PubMed

    Hebel, Christiana; Ortmann, Sylvia; Hammer, Sven; Hammer, Catrin; Fritz, Julia; Hummel, Jürgen; Clauss, Marcus

    2011-07-01

    Morphological characteristics of the forestomach, as well as reports of a natural diet that mostly excludes monocots, suggest that dikdiks (Madoqua spp.), among smallest extant ruminants, should have a 'moose-type' forestomach physiology characterised by a low degree of selective particle retention. We tested this assumption in a series of feeding experiments with 12 adult Phillip's dikdiks (Madoqua saltiana phillipsi) on three different intake levels per animal, using cobalt-EDTA as a solute marker and a 'conventional' chromium-mordanted fibre (<2 mm; mean particle size 0.63 mm) marker for the particle phase. Body mass had no influence on retention measurements, whereas food intake level clearly had. Drinking water intake was not related to the retention of the solute marker. In contrast to our expectations, the particle marker was retained distinctively longer than the solute marker. Comparisons with results in larger ruminants and with faecal particle sizes measured in dikdiks suggested that in these small animals, the chosen particle marker was above the critical size threshold, above which particle delay in the forestomach is not only due to selective particle retention (as compared to fluids), but additionally due to the ruminal particle sorting mechanism that retains particles above this threshold longer than particles below this threshold. A second study with a similar marker of a lower mean particle size (0.17 mm, which is below the faecal particle size reported for dikdiks) resulted in particle and fluid retention patterns similar to those documented in other 'moose-type' ruminants. Nevertheless, even this smaller particle marker yielded retention times that were longer than those predicted by allometric equations based on quarter-power scaling, providing further support for observations that small ruminants generally achieve longer retention times and higher digestive efficiencies than expected based on their body size. PMID:21457785

  2. The role of nano-sized manganese coatings on bone char in removing arsenic(V) from solution: Implications for permeable reactive barrier technologies.

    PubMed

    Liu, Jing; He, Lile; Dong, Faqin; Hudson-Edwards, Karen A

    2016-06-01

    Although the removal of arsenic(V) (As(V)) from solution can be improved by forming metal-bearing coatings on solid media, there has been no research to date examining the relationship between the coating and As(V) sorption performance. Manganese-coated bone char samples with varying concentrations of Mn were created to investigate the adsorption and desorption of As(V) using batch and column experiments. Breakthrough curves were obtained by fitting the Convection-Diffusion Equation (CDE), and retardation factors were used to quantify the effects of the Mn coatings on the retention of As(V). Uncoated bone char has a higher retention factor (44.7) than bone char with 0.465 mg/g of Mn (22.0), but bone char samples with between 5.02 mg/g and 14.5 mg/g Mn have significantly higher retention factors (56.8-246). The relationship between retardation factor (Y) and Mn concentration (X) is Y = 15.1 X + 19.8. Between 0.2% and 0.6% of the sorbed As is desorbed from the Mn-coated bone char at an initial pH value of 4, compared to 30% from the uncoated bone char. The ability of the Mn-coated bone char to neutralize solutions increases with increased amounts of Mn on the char. The results suggest that using Mn-coated bone char in Permeable Reactive Barriers would be an effective method for remediating As(V)-bearing solutions such as acid mine drainage. PMID:27016809

  3. Denaturation of bovine serum albumin under the action of cetyltrimethylammonium bromide, according to data from fluorescence analysis

    NASA Astrophysics Data System (ADS)

    Vlasova, I. M.; Zhuravleva, V. V.; Saletskii, A. M.

    2013-06-01

    The tryptophan fluorescence of bovine serum albumin (BSA) in solutions with different concentrations of cationic detergent cetyltrimethylammonium bromide (CTAB) at different pH is investigated, providing information on BSA denaturation under the action of CTAB. It is found that BSA denaturation under the action of CTAB at all of the investigated pH values (3.5-8.0) is a single-stage process, as determined by BSA tryptophan fluorescence quenching, by an increased degree of the BSA tryptophan fluorescence polarization, and by the values of the parameters for the rotational diffusion of BSA molecules in CTAB solutions. It is shown that the cationic detergent CTAB is more efficient for BSA denaturation at pH values higher than the BSA isoelectric point (4.9).

  4. Optimization of human serum albumin monoliths for chiral separations and high-performance affinity chromatography.

    PubMed

    Pfaunmiller, Erika L; Hartmann, Mahli; Dupper, Courtney M; Soman, Sony; Hage, David S

    2012-12-21

    Various organic-based monoliths were prepared and optimized for immobilization of the protein human serum albumin (HSA) as a binding agent for chiral separations and high-performance affinity chromatography. These monoliths contained co-polymers based on glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EDMA) or GMA and trimethylolpropane trimethacrylate (TRIM). A mixture of cyclohexanol and 1-dodecanol was used as the porogen, with the ratio of these solvents being varied along with the polymerization temperature to generate a library of monoliths. These monoliths were used with both the Schiff base and epoxy immobilization methods and measured for their final content of HSA. Monoliths showing the highest protein content were further evaluated in chromatographic studies using R/S-warfarin and d/l-tryptophan as model chiral solutes. A 2.6-2.7-fold increase in HSA content was obtained in the final monoliths when compared to similar HSA monoliths prepared according to the literature. The increased protein content made it possible for the new monoliths to provide higher retention and/or two-fold faster separations for the tested solutes when using 4.6mm i.d.× 50 mm columns. These monoliths were also used to create 4.6mm i.d.× 10 mm HSA microcolumns that could separate the same chiral solutes in only 1.5-6.0 min. The approaches used in this study could be extended to the separation of other chiral solutes and to the optimization of organic monoliths for use with additional proteins as binding agents. PMID:23010249

  5. Optimization of human serum albumin monoliths for chiral separations and high-performance affinity chromatography

    PubMed Central

    Pfaunmiller, Erika L.; Hartmann, Mahli; Dupper, Courtney M.; Soman, Sony; Hage, David S.

    2012-01-01

    Various organic-based monoliths were prepared and optimized for immobilization of the protein human serum albumin (HSA) as a binding agent for chiral separations and high-performance affinity chromatography. These monoliths contained co-polymers based on glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EDMA) or GMA and trimethylolpropane trimethacrylate (TRIM). A mixture of cyclohexanol and 1-dodecanol was used as the porogen, with the ratio of these solvents being varied along with the polymerization temperature to generate a library of monoliths. These monoliths were used with both the Schiff base and epoxy immobilization methods and measured for their final content of HSA. Monoliths showing the highest protein content were further evaluated in chromatographic studies using R/S-warfarin and d/l-tryptophan as model chiral solutes. A 2.6–2.7-fold increase in HSA content was obtained in the final monoliths when compared to similar HSA monoliths prepared according to the literature. The increased protein content made it possible for the new monoliths to provide higher retention and/or two-fold faster separations for the tested solutes when using 4.6 mm i.d. × 50 mm columns. These monoliths were also used to create 4.6 mm i.d. × 10 mm HSA microcolumns that could separate the same chiral solutes in only 1.5–6.0 min. The approaches used in this study could be extended to the separation of other chiral solutes and to the optimization of organic monoliths for use with additional proteins as binding agents. PMID:23010249

  6. Preparation and biodistribution of 188Re-labeled folate conjugated human serum albumin magnetic cisplatin nanoparticles (188Re-folate-CDDP/HSA MNPs) in vivo

    PubMed Central

    Tang, Qiu-Sha; Chen, Dao-Zhen; Xue, Wen-Qun; Xiang, Jing-Ying; Gong, Yong-Chi; Zhang, Li; Guo, Cai-Qin

    2011-01-01

    Background The purpose of this study was to develop intraperitoneal hyperthermic therapy based on magnetic fluid hyperthermia, nanoparticle-wrapped cisplatin chemotherapy, and magnetic particles of albumin. In addition, to combine the multiple-killing effects of hyperthermal targeting therapy, chemotherapy, and radiotherapy, the albumin-nanoparticle surfaces were linked with radionuclide 188Re-labeled folic acid ligand (188Re-folate-CDDP/HSA). Methods Human serum albumin was labeled with 188Re using the pre-tin method. Reaction time and optimal conditions of labeling were investigated. The particles were intravenously injected into mice, which were sacrificed at different time points. Radioactivity per gram of tissue of percent injected dose (% ID/g) was measured in vital organs. The biodistribution of 188Re-folate-CDDP/HAS magnetic nanoparticles was assessed. Results Optimal conditions for 188Re-labeled folate-conjugated albumin combined with cisplatin magnetic nanoparticles were: 0.1 mL of sodium gluconate solution (0.3 mol/L), 0.1 mL of concentrated hydrochloric acid with dissolved stannous chloride (10 mg/mL), 0.04 mL of acetic acid buffer solution (pH 5, 0.2 mol/L), 30 mg of folate-conjugated albumin combined with cisplatin magnetic nanoparticles, and 188ReO4 eluent (0.1 mL). The rate of 188Re-folate-CDDP-HSA magnetic nanoparticle formation exceeded 90%, and radiochemical purity exceeded 95%. The overall labeling rate was 83% in calf serum at 37°C. The major uptake tissues were the liver, kidney, intestine, and tumor after the 188Re-folate-CDDP/HSA magnetic nanoparticles were injected into nude mice. Uptake of 188Re-folate-CDDP/HSA magnetic nanoparticles increased gradually after injection, peaked at 8 hours with a value of 8.83 ± 1.71, and slowly decreased over 24 hours in vivo. Conclusion These results indicate that 188Re-folate-CDDP/HSA magnetic nanoparticles can be used in radionuclide-targeted cancer therapy. Surface-modified albumin nanoparticles with

  7. Experimental rock-water interactions at temperatures to 300/sup 0/C: implications for fluid flow, solute transport, and silicate mineral zoning in crustal geothermal systems

    SciTech Connect

    Potter, J.M.

    1982-01-01

    Geothermal reservoirs commonly occur in permeable volcanic rock (rhyolite, andesite, basalt) or sedimentary (sandstone) strata at temperatures below 300/sup 0/C. Knowledge of how these reservoirs develop chemically and physically has been based almost entirely on field studies. Four types of experiments were conducted to supplement available data on the chemistry, mineralogy, and fluid flow aspects of hydrothermal processes occurring in crustal geothermal systems: (1) agitated rock-water experiments; (2) high temperature flow through experiments; (3) low temperature permeability experiments; and (4) corrosion monitoring experiments. Initial experiments reacted rhyolite glass and holocrystalline basalt with water-NaCl solutions at 300/sup 0/C in agitated hydrothermal equipment. Concentrations of components in solution depend on initial salinity, rock type, and particle size. The secondary phases consist of zeolites, clay, and feldspar minerals and the alteration assemblage is dependent on both initial salinity, rock type, and duration of the experiment. A second set of experiments were conducted at 300/sup 0/C using the rhyolite glass in a flow through type of apparatus. Compositions of outlet fluids show a dependence of fluid flow rate and core length.

  8. Thermal transitions in serum amyloid A in solution and on the lipid: implications for structure and stability of acute-phase HDL.

    PubMed

    Jayaraman, Shobini; Haupt, Christian; Gursky, Olga

    2015-08-01

    Serum amyloid A (SAA) is an acute-phase protein that circulates mainly on plasma HDL. SAA interactions with its functional ligands and its pathogenic deposition in reactive amyloidosis depend, in part, on the structural disorder of this protein and its propensity to oligomerize. In vivo, SAA can displace a substantial fraction of the major HDL protein, apoA-I, and thereby influence the structural remodeling and functions of acute-phase HDL in ways that are incompletely understood. We use murine SAA1.1 to report the first structural stability study of human plasma HDL that has been enriched with SAA. Calorimetric and spectroscopic analyses of these and other SAA-lipid systems reveal two surprising findings. First, progressive displacement of the exchangeable fraction of apoA-I by SAA has little effect on the structural stability of HDL and its fusion and release of core lipids. Consequently, the major determinant for HDL stability is the nonexchangeable apoA-I. A structural model explaining this observation is proposed, which is consistent with functional studies in acute-phase HDL. Second, we report an α-helix folding/unfolding transition in SAA in the presence of lipid at near-physiological temperatures. This new transition may have potentially important implications for normal functions of SAA and its pathogenic misfolding. PMID:26022803

  9. The solution structure of the outer membrane lipoprotein OmlA from Xanthomonas axonopodis pv. citri reveals a protein fold implicated in protein-protein interaction.

    PubMed

    Vanini, Marina Marques Teixeira; Spisni, Alberto; Sforça, Maurício Luis; Pertinhez, Thelma Aguiar; Benedetti, Celso Eduardo

    2008-06-01

    The outer membrane lipoprotein A (OmlA) belongs to a family of bacterial small lipoproteins widely distributed across the beta and gamma proteobacteria. Although the role of numerous bacterial lipoproteins is known, the biological function of OmlA remains elusive. We found that in the citrus canker pathogen, Xanthomonas axonopodis pv. citri (X. citri), OmlA is coregulated with the ferric uptake regulator (Fur) and their expression is enhanced when X. citri is grown on citrus leaves, suggesting that these proteins are involved in plant-pathogen interaction. To gain insights into the function of OmlA, its conformational and dynamic features were determined by nuclear magnetic resonance. The protein has highly flexible N- and C- termini and a structurally well defined core composed of three beta-strands and two small alpha-helices, which pack against each other forming a two-layer alpha/beta scaffold. This protein fold resembles the domains of the beta-lactamase inhibitory protein BLIP, involved in protein-protein binding. In conclusion, the structure of OmlA does suggest that this protein may be implicated in protein-protein interactions required during X. citri infection. PMID:18186471

  10. Enhanced tumor delivery and antitumor response of doxorubicin-loaded albumin nanoparticles formulated based on a Schiff base.

    PubMed

    Li, Fang; Zheng, Chunli; Xin, Junbo; Chen, Fangcheng; Ling, Hua; Sun, Linlin; Webster, Thomas J; Ming, Xin; Liu, Jianping

    2016-01-01

    A novel method was developed here to prepare albumin-based nanoparticles (NPs) for improving the therapeutic and safety profiles of chemotherapeutic agents. This approach involved crosslinking bovine serum albumin (BSA) using a Schiff base-containing vanillin, into NPs and loading doxorubicin (DOX) into the NPs by incubation. The resultant NPs (DOX-BSA-V-NPs) displayed a particle size of 100.5±1.3 nm with a zeta potential of -23.05±1.45 mV and also showed high drug-loading efficiency and excellent stability with respect to storage and temperature. The encapsulation of DOX into the BSA-V-NPs was confirmed by dynamic scanning calorimetry and Raman spectroscopy. DOX-BSA-V-NPs exhibited a significantly faster DOX release at pH 6.5 than pH 7.4, as well as in a solution with a higher glutathione concentration. In vitro studies showed that the cellular uptake of DOX-BSA-V-NPs was time-dependent, concentration-dependent, and faster than free DOX, while the cytotoxicity of DOX-BSA-V-NPs (IC50 value of 3.693 μg/mL) was superior to free DOX (IC50 value of 4.007 μg/mL). More importantly, DOX-BSA-V-NPs showed a longer mean survival time of 24.83 days, a higher tumor inhibition rate of 56.66%, and a decreased distribution in the heart than other DOX formulations in animal studies using a tumor xenograft model. Thus, the vanillin-based albumin NPs were shown here to be a promising carrier for tumor-targeted delivery of chemotherapeutic agents and, thus, should be further studied. PMID:27574421

  11. Enhanced tumor delivery and antitumor response of doxorubicin-loaded albumin nanoparticles formulated based on a Schiff base

    PubMed Central

    Li, Fang; Zheng, Chunli; Xin, Junbo; Chen, Fangcheng; Ling, Hua; Sun, Linlin; Webster, Thomas J; Ming, Xin; Liu, Jianping

    2016-01-01

    A novel method was developed here to prepare albumin-based nanoparticles (NPs) for improving the therapeutic and safety profiles of chemotherapeutic agents. This approach involved crosslinking bovine serum albumin (BSA) using a Schiff base-containing vanillin, into NPs and loading doxorubicin (DOX) into the NPs by incubation. The resultant NPs (DOX-BSA-V-NPs) displayed a particle size of 100.5±1.3 nm with a zeta potential of −23.05±1.45 mV and also showed high drug-loading efficiency and excellent stability with respect to storage and temperature. The encapsulation of DOX into the BSA-V-NPs was confirmed by dynamic scanning calorimetry and Raman spectroscopy. DOX-BSA-V-NPs exhibited a significantly faster DOX release at pH 6.5 than pH 7.4, as well as in a solution with a higher glutathione concentration. In vitro studies showed that the cellular uptake of DOX-BSA-V-NPs was time-dependent, concentration-dependent, and faster than free DOX, while the cytotoxicity of DOX-BSA-V-NPs (IC50 value of 3.693 μg/mL) was superior to free DOX (IC50 value of 4.007 μg/mL). More importantly, DOX-BSA-V-NPs showed a longer mean survival time of 24.83 days, a higher tumor inhibition rate of 56.66%, and a decreased distribution in the heart than other DOX formulations in animal studies using a tumor xenograft model. Thus, the vanillin-based albumin NPs were shown here to be a promising carrier for tumor-targeted delivery of chemotherapeutic agents and, thus, should be further studied. PMID:27574421

  12. A Novel Albumin-Based Tissue Scaffold for Autogenic Tissue Engineering Applications

    PubMed Central

    Li, Pei-Shan; -Liang Lee, I.; Yu, Wei-Lin; Sun, Jui-Sheng; Jane, Wann-Neng; Shen, Hsin-Hsin

    2014-01-01

    Tissue scaffolds provide a framework for living tissue regeneration. However, traditional tissue scaffolds are exogenous, composed of metals, ceramics, polymers, and animal tissues, and have a defined biocompatibility and application. This study presents a new method for obtaining a tissue scaffold from blood albumin, the major protein in mammalian blood. Human, bovine, and porcine albumin was polymerised into albumin polymers by microbial transglutaminase and was then cast by freeze-drying-based moulding to form albumin tissue scaffolds. Scanning electron microscopy and material testing analyses revealed that the albumin tissue scaffold possesses an extremely porous structure, moderate mechanical strength, and resilience. Using a culture of human mesenchymal stem cells (MSCs) as a model, we showed that MSCs can be seeded and grown in the albumin tissue scaffold. Furthermore, the albumin tissue scaffold can support the long-term osteogenic differentiation of MSCs. These results show that the albumin tissue scaffold exhibits favourable material properties and good compatibility with cells. We propose that this novel tissue scaffold can satisfy essential needs in tissue engineering as a general-purpose substrate. The use of this scaffold could lead to the development of new methods of artificial fabrication of autogenic tissue substitutes. PMID:25034369

  13. Glycation alters ligand binding, enzymatic, and pharmacological properties of human albumin.

    PubMed

    Baraka-Vidot, Jennifer; Planesse, Cynthia; Meilhac, Olivier; Militello, Valeria; van den Elsen, Jean; Bourdon, Emmanuel; Rondeau, Philippe

    2015-05-19

    Albumin, the major circulating protein in blood plasma, can be subjected to an increased level of glycation in a diabetic context. Albumin exerts crucial pharmacological activities through its drug binding capacity, i.e., ketoprofen, and via its esterase-like activity, allowing the conversion of prodrugs into active drugs. In this study, the impact of the glucose-mediated glycation on the pharmacological and biochemical properties of human albumin was investigated. Aggregation product levels and the redox state were quantified to assess the impact of glycation-mediated changes on the structural properties of albumin. Glucose-mediated changes in ketoprofen binding properties and esterase-like activity were evaluated using fluorescence spectroscopy and p-nitrophenyl acetate hydrolysis assays, respectively. With the exception of oxidative parameters, significant dose-dependent alterations in biochemical and functional properties of in vitro glycated albumin were observed. We also found that the dose-dependent increase in levels of glycation and protein aggregation and average molecular mass changes correlated with a gradual decrease in the affinity of albumin for ketoprofen and its esterase-like property. In parallel, significant alterations in both pharmacological properties were also evidenced in albumin purified from diabetic patients. Partial least-squares regression analyses established a significant correlation between glycation-mediated changes in biochemical and pharmacological properties of albumin, highlighting the important role for glycation in the variability of the drug response in a diabetic situation. PMID:25915793

  14. Functional and rheological properties of amaranth albumins extracted from two Mexican varieties.

    PubMed

    Silva-Sánchez, C; González-Castañeda, J; de León-Rodríguez, A; Barba de la Rosa, A P

    2004-01-01

    The functional and rheological properties of amaranth albumins isolates extracted from two new Mexican varieties were determined. Functional properties tested were protein solubility, foaming, water and oil absorption capacities, emulsifying activity, and emulsion stability. The maximum solubility values for both amaranth albumins were found above pH 6 and values were compared to the solubility of egg albumins. Albumins from amaranth showed excellent foaming capacity and foaming stability at pH 5, suggesting that this protein could be used as whipping agents as egg albumins, also the water and oil absorption capacities reached their maximum values at acidic pH, suggesting that amaranth albumins could be appropriate in preparation of acidic foods. The rheological test based on farinograms and alveograms showed that wheat flour supplemented with 1% amaranth albumins improves the dough properties due to higher mixing stability and the bread had better crumb characteristics. In addition of the known high nutritional values of amaranth albumins, our results indicate the high potential for use of these proteins as an ingredient in food preparations. PMID:15678726

  15. Species Dependence of [64Cu]Cu-Bis(thiosemicarbazone) Radiopharmaceutical Binding to Serum Albumins

    PubMed Central

    Basken, Nathan E.; Mathias, Carla J.; Lipka, Alexander E.; Green, Mark A.

    2008-01-01

    Introduction Interactions of three copper(II) bis(thiosemicarbazone) PET radiopharmaceuticals with human serum albumin, and the serum albumins of four additional mammalian species, were evaluated. Methods 64Cu-labeled diacetyl bis(N4-methylthiosemicarbazonato)copper(II) (Cu-ATSM), pyruvaldehyde bis(N4-methylthiosemicarbazonato)copper(II) (Cu-PTSM), and ethylglyoxal bis(thiosemicarbazonato)copper(II) (Cu-ETS) were synthesized and their binding to human, canine, rat, baboon, and porcine serum albumins quantified by ultrafiltration. Protein binding was also measured for each tracer in human, porcine, rat, and mouse serum. Results The interaction of these neutral, lipophilic copper chelates with serum albumin is highly compound- and species-dependent. Cu-PTSM and Cu-ATSM exhibit particularly high affinity for human serum albumin (HSA), while the albumin binding of Cu-ETS is relatively insensitive to species. At HSA concentrations of 40 mg/mL, “% Free” (non-albumin-bound) levels of radiopharmaceutical were 4.0 ± 0.1%; 5.3 ± 0.2%; and 38.6 ± 0.8% for Cu-PTSM; Cu-ATSM; and Cu-ETS, respectively. Conclusions Species-dependent variations in radiopharmaceutical binding to serum albumin may need to be considered when using animal models to predict the distribution and kinetics of these compounds in humans. PMID:18355683

  16. PHOS-Select Iron Affinity beads enrich peptides for detection of organophosphorus adducts on albumin

    PubMed Central

    Jiang, Wei; Dubrovskii, Yaroslav A; Podolskaya, Ekaterina P; Murashko, Ekaterina A; Babakov, Vladimir; Nachon, Florian; Masson, Patrick; Schopfer, Lawrence M; Lockridge, Oksana

    2013-01-01

    Albumin is covalently modified by organophosphorus toxicants (OP) on tyrosine 411, but less than 1% of albumin is modified in humans by lethal OP doses that inhibit 95% of plasma butyrylcholinesterase. A method that enriches OP-modified albumin peptides could aid analysis of low dose exposures. Soman or chlorpyrifos oxon treated human plasma was digested with pepsin. Albumin peptides were enriched by binding to Fe3+ beads at pH 11 and eluted with pH 2.6 buffer. Similarly, mouse and guinea pig albumin modified by chlorpyrifos oxon were digested with pepsin and enriched by binding to Fe3+ beads. Peptides were identified by MALDI-TOF/TOF mass spectrometry. PHOS-select Iron Affinity beads specifically enriched albumin peptides VRY411TKKVPQVST and LVRY411TKKVPQVST in a pepsin digest of human plasma. The unmodified as well as OP-modified peptides bound to the beads. The binding capacity of 500 μl beads was the pepsin digest of 2.1 μL human plasma. The limit of detection was 0.2% of OP-modified albumin peptide in 0.43 μL plasma. Enrichment of OP-modified albumin peptides by binding to Fe3+ beads is a method with potential application to diagnosis of OP pesticide and nerve agent exposure in humans, mice, and guinea pigs. PMID:24187955

  17. A Novel Albumin-Based Tissue Scaffold for Autogenic Tissue Engineering Applications

    NASA Astrophysics Data System (ADS)

    Li, Pei-Shan; -Liang Lee, I.; Yu, Wei-Lin; Sun, Jui-Sheng; Jane, Wann-Neng; Shen, Hsin-Hsin

    2014-07-01

    Tissue scaffolds provide a framework for living tissue regeneration. However, traditional tissue scaffolds are exogenous, composed of metals, ceramics, polymers, and animal tissues, and have a defined biocompatibility and application. This study presents a new method for obtaining a tissue scaffold from blood albumin, the major protein in mammalian blood. Human, bovine, and porcine albumin was polymerised into albumin polymers by microbial transglutaminase and was then cast by freeze-drying-based moulding to form albumin tissue scaffolds. Scanning electron microscopy and material testing analyses revealed that the albumin tissue scaffold possesses an extremely porous structure, moderate mechanical strength, and resilience. Using a culture of human mesenchymal stem cells (MSCs) as a model, we showed that MSCs can be seeded and grown in the albumin tissue scaffold. Furthermore, the albumin tissue scaffold can support the long-term osteogenic differentiation of MSCs. These results show that the albumin tissue scaffold exhibits favourable material properties and good compatibility with cells. We propose that this novel tissue scaffold can satisfy essential needs in tissue engineering as a general-purpose substrate. The use of this scaffold could lead to the development of new methods of artificial fabrication of autogenic tissue substitutes.

  18. Colloids Versus Albumin in Large Volume Paracentesis to Prevent Circulatory Dysfunction: Evidence-based Case Report.

    PubMed

    Widjaja, Felix F; Khairan, Paramita; Kamelia, Telly; Hasan, Irsan

    2016-04-01

    Large volume paracentesis may cause paracentesis induced circulatory dysfunction (PICD). Albumin is recommended to prevent this abnormality. Meanwhile, the price of albumin is too expensive and there should be another alternative that may prevent PICD. This report aimed to compare albumin to colloids in preventing PICD. Search strategy was done using PubMed, Scopus, Proquest, dan Academic Health Complete from EBSCO with keywords of "ascites", "albumin", "colloid", "dextran", "hydroxyethyl starch", "gelatin", and "paracentesis induced circulatory dysfunction". Articles was limited to randomized clinical trial and meta-analysis with clinical question of "In hepatic cirrhotic patient undergone large volume paracentesis, whether colloids were similar to albumin to prevent PICD". We found one meta-analysis and four randomized clinical trials (RCT). A meta analysis showed that albumin was still superior of which odds ratio 0.34 (0.23-0.51). Three RCTs showed the same results and one RCT showed albumin was not superior than colloids. We conclude that colloids could not constitute albumin to prevent PICD, but colloids still have a role in patient who undergone paracentesis less than five liters. PMID:27550886

  19. Unexpected Normal Colloid Osmotic Pressure in Clinical States with Low Serum Albumin

    PubMed Central

    Michelis, Regina; Sela, Shifra; Zeitun, Teuta; Geron, Ronit; Kristal, Batya

    2016-01-01

    Background In clinical states associated with systemic oxidative stress (OS) and inflammation such as chronic kidney disease (CKD), oxidative modifications of serum albumin impair its quantification, resulting in apparent hypoalbuminemia. As the maintenance of oncotic pressure/colloid osmotic pressure (COP) is a major function of albumin, this study examined the impact of albumin oxidation on COP, both in-vivo and in-vitro. Methods Patients with proteinuria and patients on chronic hemodialysis (HD) with systemic inflammation and OS were enrolled. Blood samples were collected from 134 subjects: 32 healthy controls (HC), proteinuric patients with high (n = 17) and low (n = 31) systemic inflammation and from 54 patients on chronic hemodialysis (HD) with the highest levels of OS and inflammation. Results In-vitro oxidized albumin showed significantly higher COP values than non-oxidized albumin at identical albumin levels. In vivo, in hypoalbuminemic HD patients with the highest OS and inflammation, COP values were also higher than expected for the low albumin levels. The contribution to COP by other prevalent plasma proteins, such as fibrinogen and immunoglobulins was negligible. We imply that the calculation of COP based on albumin levels should be revisited in face of OS and inflammation. Hence, in hypoalbuminemic proteinuric patients with systemic OS and inflammation the assumption of low COP should be verified by its measurements. PMID:27453993

  20. PHOS-select iron affinity beads enrich peptides for the detection of organophosphorus adducts on albumin.

    PubMed

    Jiang, Wei; Dubrovskii, Yaroslav A; Podolskaya, Ekaterina P; Murashko, Ekaterina A; Babakov, Vladimir; Nachon, Florian; Masson, Patrick; Schopfer, Lawrence M; Lockridge, Oksana

    2013-12-16

    Albumin is covalently modified by organophosphorus toxicants (OP) on tyrosine 411, but less than 1% of albumin is modified in humans by lethal OP doses that inhibit 95% of plasma butyrylcholinesterase. A method that enriches OP-modified albumin peptides could aid analysis of low dose exposures. Soman or chlorpyrifos oxon treated human plasma was digested with pepsin. Albumin peptides were enriched by binding to Fe(3+) beads at pH 11 and eluted with pH 2.6 buffer. Similarly, mouse and guinea pig albumin modified by chlorpyrifos oxon were digested with pepsin and enriched by binding to Fe(3+) beads. Peptides were identified by MALDI-TOF/TOF mass spectrometry. PHOS-select iron affinity beads specifically enriched albumin peptides VRY411TKKVPQVST and LVRY411TKKVPQVST in a pepsin digest of human plasma. The unmodified as well as OP-modified peptides bound to the beads. The binding capacity of 500 μL of beads was the pepsin digest of 2.1 μL of human plasma. The limit of detection was 0.2% of OP-modified albumin peptide in 0.43 μL of plasma. Enrichment of OP-modified albumin peptides by binding to Fe(3+) beads is a method with potential application to diagnosis of OP pesticide and nerve agent exposure in humans, mice, and guinea pigs. PMID:24187955

  1. TEMPORAL AND SPATIAL EXPRESSION OF 2S ALBUMIN IN CASTOR (Ricinus communis L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We studied the temporal and spatial expression of the 2S albumin in castor (Ricinus communis L.) during seed development, germination, post-germination, and plant development. Quantitative PCR analysis showed that the 2S albumin transcript accumulated to a maximum level at the middle of seed develop...

  2. A Computational Study of the Hydrolysis of dGTP Analogues with Halomethylene Modified Leaving Groups in Solution: Implications for the Mechanism of DNA Polymerases

    PubMed Central

    Kamerlin, Shina C. L.; McKenna, Charles E.; Goodman, Myron F.; Warshel, A.

    2009-01-01

    DNA polymerases are a family of enzymes responsible for regulating DNA replication and repair, which in turn maintains the integrity of the genome. However, despite intensive kinetic, crystallographic and computational studies, elucidation of the detailed enzymatic mechanism still presents a significant challenge. We recently developed an alternative strategy for exploring the fidelity and mechanism of DNA polymerases, by probing leaving group effects on nucleotidyl transfer using a series of dGTP bisphosphonate analogues in which the β, γ-bridging oxygen was replaced by a series of substituted methylene groups (X=CYZ, where Y,Z=H, halogen or other substituent). Pre-steady state kinetic measurements of DNA polymerase-catalyzed incorporation of correctly base paired (R) and mispaired (W) analogues demonstrated a strong linear free energy relationship (LFER) between the polymerase rate constant (kpol) and the highest pKa of the free bisphosphonic acid corresponding to the leaving group. However, unexpectedly, the data segregated into two distinctly different linear correlations depending on the nature of the substituent. The discrepancy between the two lines was considerably greater when the dGTP analogue formed an incorrect (G•T) rather than a correct (G•C) base pair, although the reason for this phenomenon remains unexplained. Here, we have evaluated the complete free energy surfaces for bisphosphonate hydrolysis in aqueous solution and evaluated the corresponding LFER. Our study, which employs several alternative solvation models, finds a split of the calculated LFER for the mono- and dihalogen compounds into two parallel lines, reflecting their behavior in the polymerase-catalyzed condensation reaction. We suggest that the division into two linear subsets may be a generalized solvation phenomenon involving the overall electrostatic interaction between the substrates and enzyme and would be observed in solution in the absence of the enzyme. In contrast, the

  3. Joint neutron crystallographic and NMR solution studies of Tyr residue ionization and hydrogen bonding: Implications for enzyme-mediated proton transfer

    DOE PAGESBeta

    Michalczyk, Ryszard; Unkefer, Clifford J.; Bacik, John -Paul; Schrader, Tobias E.; Ostermann, Andreas; Kovalevsky, Andrey Y.; McKenna, Robert; Fisher, Suzanne Zoe

    2015-05-05

    Proton transfer is a fundamental mechanism at the core of many enzyme-catalyzed reactions. It is also exquisitely sensitive to a number of factors, including pH, electrostatics, proper active-site geometry, and chemistry. Carbonic anhydrase has evolved a fast and efficient way to conduct protons through a combination of hydrophilic amino acid side chains that coordinate a highly ordered H-bonded water network. This study uses a powerful approach, combining NMR solution studies with neutron protein crystallography, to determine the effect of pH and divalent cations on key residues involved in proton transfer in human carbonic anhydrase. Lastly, the results have broad implicationsmore » for our understanding of proton transfer and how subtle changes in ionization and H-bonding interactions can modulate enzyme catalysis.« less

  4. Conformational study of two linear hexapeptides by two-dimensional NMR and computer-simulated modeling: implication for peptide cyclization in solution.

    PubMed

    Chiou, A J; Ong, G T; Wang, K T; Chiou, S H; Wu, S H

    1996-02-15

    Two linear peptides, D-leucyl-L-prolyl-L-isoleucyl-L-valyl-L-alanyl-beta-alanine (I) and D-leucyl-L-prolyl-L-isoleucyl-L-valyl-N-methyl-L-alanyl-beta-alanine (II), whose sequences were designed from protodestruxin and desmethyldestruxin B by replacing D-leucic acid with D-leucine, two cyclic hexadepsipeptides with insecticidal and immunodepressant activities, have been found to be cyclized in unusually high yields (>85%). In order to gain insight into the conformation and the relative flexibility of different constituent residues in these linear peptides, we have applied various techniques of 2D-NMR spectroscopy coupled with dynamic simulated annealing by computer modeling to establish the solution conformations of these two linear peptides. Based on the derived structures, it is found that the distances between N- and C-terminal residues of both peptides are short enough to facilitate the cyclization, thus collaborating the observation of favorable cyclization yields for both linear peptides. PMID:8605029

  5. Biologically active protein fragments containing specific binding regions of serum albumin or related proteins

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor)

    1998-01-01

    In accordance with the present invention, biologically active protein fragments can be constructed which contain only those specific portions of the serum albumin family of proteins such as regions known as subdomains IIA and IIIA which are primarily responsible for the binding properties of the serum albumins. The artificial serums that can be prepared from these biologically active protein fragments are advantageous in that they can be produced much more easily than serums containing the whole albumin, yet still retain all or most of the original binding potential of the full albumin proteins. In addition, since the protein fragment serums of the present invention can be made from non-natural sources using conventional recombinant DNA techniques, they are far safer than serums containing natural albumin because they do not carry the potentially harmful viruses and other contaminants that will be found in the natural substances.

  6. Quantitative determination of biological sulfhydryl groups by postcolumn derivatization and elucidation of microheterogeneity of serum albumins.

    PubMed

    Yasuhara, T; Nokihara, K

    1998-08-15

    A quantitative analytical system for biological sulfhydryl compounds has been developed using an ion-pair reagent with isocratic elution and an on-line postcolumn derivatization with Ellman-type reagents. As human or bovine serum albumin has 35 cysteinyl residues, one cysteinyl residue exists as a free sulfhydryl moiety, and this gives rise to the microheterogeneity in serum albumin. Here we report for the first time the quantitative characterization of the microheterogeneity of serum albumin. Cysteine was found to be the major molecule attached to the sulfydryl group of the serum albumins. Although glutathione could not be detected, the Cys-Gly element of glutathione was found. Freshly prepared human serum albumin from healthy volunteers contained 0.46 nmol of Cys/mL of serum, 0.24 nmol of Cys-Gly/mL of serum, and very small amounts of glutathione (0.02 nmol/mL). PMID:9726170

  7. Iron absorption in humans: bovine serum albumin compared with beef muscle and egg white

    SciTech Connect

    Hurrell, R.F.; Lynch, S.R.; Trinidad, T.P.; Dassenko, S.A.; Cook, J.D.

    1988-01-01

    We studied the influence of bovine serum albumin and beef meat on nonheme iron absorption in humans and on dialyzable iron in vitro. The addition of serum albumin to a maize gruel had no significant effect on nonheme Fe absorption whereas the addition of beef meat caused a threefold increase. When added to a bread meal, serum albumin caused a modest 60% increase in nonheme Fe absorption and beef meat had no effect. When added to a protein-free meal, serum albumin reduced Fe absorption by 47% compared with a 72% reduction on addition of egg white. The bioavailability of nonheme Fe from meals containing serum albumin was consistently overestimated by the in vitro technique. We conclude that the facilitation of nonheme Fe absorption by meat is not a general property of all animal protein but is better explained by the action of one or more specific animal tissues.

  8. [Isoelectric spectra of liver tissue and blood serum albumin for rabbits of different age].

    PubMed

    Sopkina, D A; Ostolovskiĭ, E M; Ivlev, V N

    1978-01-01

    The isoelectric spectrum of albumin isolated from the liver and blood serum of 30-, 45- and 90-day rabbits was studied. By the method of isoelectric focusing in the boron-borate buffer--mannitol system. It is shown that the liver albumin displays heterogeneity ans is separated into four-five fractions, with pJ 4.8-6.0. Age peculiarities are found for the isoelectric spectrum of this protein. The serum albumin spectrum for rabbits of the studied age groups is characterized by the presence of a homogeneous peak with pJ 5.59, 5.57 and 5.47 corresponding to 30, 45 and 90-day age, respectively. Identity of serum albumin and protein of some liver albumin spectrum components is established by analyzing the pattern of the isoelectric spectrum for a mixture of preparations of 90-day rabbit proteins under comparison. PMID:34911

  9. A comparative analysis on the binding characteristics of various mammalian albumins towards a multitherapeutic agent, pinostrobin

    PubMed Central

    FEROZ, Shevin R.; SUMI, Rumana A.; MALEK, Sri N.A.; TAYYAB, Saad

    2014-01-01

    The interaction of pinostrobin (PS), a multitherapeutic agent with serum albumins of various mammalian species namely, goat, bovine, human, porcine, rabbit, sheep and dog was investigated using fluorescence quench titration and competitive drug displacement experiments. Analysis of the intrinsic fluorescence quenching data revealed values of the association constant, Ka in the range of 1.49 – 6.12 × 104 M−1, with 1:1 binding stoichiometry. Based on the PS–albumin binding characteristics, these albumins were grouped into two classes. Ligand displacement studies using warfarin as the site I marker ligand correlated well with the binding data. Albumins from goat and bovine were found to be closely similar to human albumin on the basis of PS binding characteristics. PMID:25519455

  10. A comparative analysis on the binding characteristics of various mammalian albumins towards a multitherapeutic agent, pinostrobin.

    PubMed

    Feroz, Shevin R; Sumi, Rumana A; Malek, Sri N A; Tayyab, Saad

    2015-01-01

    The interaction of pinostrobin (PS), a multitherapeutic agent with serum albumins of various mammalian species namely, goat, bovine, human, porcine, rabbit, sheep and dog was investigated using fluorescence quench titration and competitive drug displacement experiments. Analysis of the intrinsic fluorescence quenching data revealed values of the association constant, K(a) in the range of 1.49 - 6.12 × 10(4) M(-1), with 1:1 binding stoichiometry. Based on the PS-albumin binding characteristics, these albumins were grouped into two classes. Ligand displacement studies using warfarin as the site I marker ligand correlated well with the binding data. Albumins from goat and bovine were found to be closely similar to human albumin on the basis of PS binding characteristics. PMID:25519455

  11. Role of albumin in diseases associated with severe systemic inflammation: Pathophysiologic and clinical evidence in sepsis and in decompensated cirrhosis.

    PubMed

    Artigas, Antonio; Wernerman, Jan; Arroyo, Vicente; Vincent, Jean-Louis; Levy, Mitchell

    2016-06-01

    The metabolism of albumin in inflammatory states such as sepsis or major surgery is complex and still not well characterized. Nevertheless, in inflammatory states, albumin synthesis has been observed to increase. By contrast, in decompensated cirrhosis, a disease characterized by systemic inflammation, albumin synthesis by the liver may decrease to 30% to 50% of normal values. Furthermore, in these conditions, there are high capillary leakage and altered albumin kinetics. The discussion regarding the effect of exogenous albumin administration on intravascular volume in inflammatory states should therefore address albumin turnover. To add complexity to our understanding of the effects of albumin, there are many data indicating that the therapeutic action of albumin is mediated not only through the impact on plasma volume expansion but also through a modulatory effect on inflammation and oxidative stress. All these characteristics are relevant to diseases associated with systemic inflammation including sepsis and decompensated cirrhosis. PMID:26831575

  12. [RNA responsible for conferring a DNase I sensitive structure on albumin gene in assembled chromatin].

    PubMed

    Lv, Zhan-Jun; Wang, Xiu-Fang; Zhai, Yu; Song, Shu-Xia

    2003-01-01

    Although the set of genes is virtually the same in all tissues,differential gene expression is appeared in cells of different kinds. Differentiation and ageing are associated with regulation of gene expression that is a fundamental mechanism in eukaryotic development and survival. The sensitivity to DNase I of actively transcribed genes seems to be a general phenomenon. The purpose of the study is to test whether RNAs obtained from different organs or cells can enhance susceptibility of albumin gene to DNase I digestion in BALB/c mouse brain chromatin assembled.RNAs extracted from rat liver, lung, kidney, brain, tRNA from yeast and synthesized RNAs (23 nt completed with mouse alb gene) were added to a system of chromatin reconstitution that was achieved by dialysis from high ionic strength solution. Assembled chromatin was digested with DNase I (12.5 microg/mL) at 20 degrees for 1 min, then PCR assay was used to detect the level of albumin gene digested. PCR products (1200 bp) were run on a 6% polyacylamide gel and analyzed by silver stain assay. RNAs from different organs and synthesized RNAs all increased the sensitivity of albumin gene to DNase I attack in mouse assembled chromatin. The effect was more obvious in liver and lung RNAs than in kidney and brain ones. tRNA from yeast did not enhance the sensitivity of albumin gene to DNase I digestion. RNA increased albumin gene sensitivity to DNase I in a dose-dependent manner. We report here for the first time that RNAs can enhance susceptibility of albumin gene to DNase I digestion. The effect is associated with RNA sources or sequences. It is generally agreed that the formation of gene sensitivity to DNase I, by unfolding of a tightly packed chromatin fiber, is the first step in gene activation, then RNAs that recognize complementary DNA sequences may be the specific factors that affect DNA supercoiling and determine the sensitivity of gene to DNase I digestion. Here we describes "RNA Population Gene Activating

  13. Preparation and Characterization of PEG-albumin-curcumin Nanoparticles Intended to Treat Breast Cancer

    PubMed Central

    Thadakapally, R.; Aafreen, Arshiya; Aukunuru, J.; Habibuddin, M.; Jogala, S.

    2016-01-01

    The aim of present research was to prepare novel serum stable long circulating polymeric nanoparticles for curcumin with a modification to the well known and novel nanoparticle albumin bound technology. polyethylene glycol-albumin-curcumin nanoparticles were prepared using serum albumin and poly ethylene glycol using desolvation technique. Nanoparticles were characterized for encapsulation efficiency, particle size and surface morphology. Drug excipient compatibility was determined using fourier transform infrared spectroscopy. Physical state of the drug in the formulations was known by differential scanning colorimetry. In vitro release and solubility of the drug from nanoparticles were determined. In vivo Drug release, tissue uptake and kupffer cell uptake was determined with optimized nanoformulation in rats after intravenous administration. Cell viability assay was determined using breast cancer cell line MD-MB-231. Entrapment efficiency for prepared nanoparticle was above 95%. The polyethylene glycol-albumin-curcumin nanoparticles exhibited an interesting release profile with small initial burst followed by slower and controlled release. Solubility of the drug from the formulation was increased. A sustained release of drug from nanoparticles was observed for 35 days in both in vitro and in vivo studies with the optimized formulation. Polyethylene glycol-albumin-curcumin nanoparticles showed lesser liver and kupffer cell uptake as compared to that of curcumin-albumin nanoparticles suggesting the bestowment of stealthness to nanoparticles with pegylation. Also, the antiproliferative activity of polyethylene glycol-albumin-curcumin nanoparticle formulation was more as compared to native curcumin. Polyethylene glycol-albumin-curcumin nanoparticles thus developed can be conveniently used in breast cancer with improved efficacy compared to conventional therapies and as an alternate to nanoparticle albumin bound technology which is used in producing Abraxane, albumin

  14. Albumin transport across pulmonary capillary-interstitial barrier in anesthetized dogs.

    PubMed

    Ishibashi, M; Reed, R K; Townsley, M I; Parker, J C; Taylor, A E

    1991-05-01

    To evaluate albumin transport across the pulmonary capillary endothelial and interstitial barriers, we simultaneously measured blood-to-tissue (QA,t) and blood-to-lymph (QA,l) clearances of 125I-radiolabeled albumin as well as endogenous albumin clearance (Qa,l) in the canine lung in vivo (n = 10). Steady-state prenodal lung lymph flows (Qw,l) and protein clearances were measured over a 2-h period at a constant capillary pressure (Pc, 13-33 cmH2O). Comparison between QA,t and QA,l as a function of Pc suggests that little of the albumin that crossed the capillary wall remained in the lung tissue, with most leaving in the lymph. Qw,l increased significantly as Pc increased, but lung tissue water was minimally affected. From the ratio of the clearance-Pc slopes for albumin and water, the albumin reflection coefficient was estimated to be 0.81 using QA,l and Qw,l and 0.56 using Qa,l and Qw,l. The permeability surface area product for the sum of blood-to-tissue and blood-to-lymph fluxes of labeled albumin (QA,t + QA,l) was 31 +/- 9 microliters/min, whereas that calculated from the blood-to-lymph flux of endogenous albumin (Qa,l) was 97 +/- 22 microliters/min. These data suggest that 1) both tissue and lymph accumulations of albumin must be considered when microvascular permeability is evaluated using protein tracers; 2) lymph clearance, but not tissue accumulation of albumin, was filtration dependent; and 3) lymph flow was an important contributor to the safety factor against edema formation over a moderate range of capillary pressures. PMID:1864792

  15. Anisotropic energy flow and allosteric ligand binding in albumin

    PubMed Central

    Li, Guifeng; Magana, Donny; Dyer, R. Brian

    2014-01-01

    Allosteric interactions in proteins generally involve propagation of local structural changes through the protein to a remote site. Anisotropic energy transport is thought to couple the remote sites, but the nature of this process is poorly understood. Here, we report the relationship between energy flow through the structure of bovine serum albumin and allosteric interactions between remote ligand binding sites of the protein. Ultrafast infrared spectroscopy is used to probe the flow of energy through the protein backbone following excitation of a heater dye, a metalloporphyrin or malachite green, bound to different binding sites in the protein. We observe ballistic and anisotropic energy flow through the protein structure following input of thermal energy into the flexible ligand binding sites, without local heating of the rigid helix bundles that connect these sites. This efficient energy transport mechanism enables the allosteric propagation of binding energy through the connecting helix structures. PMID:24445265

  16. Detection of esophageal ulcerations with technetium-99m albumin sucralfate

    SciTech Connect

    Goff, J.S.; Adcock, K.A.; Schmelter, R.

    1986-07-01

    Technetium-99m albumin-sucralfate ((/sup 99m/Tc)Su) can be used to demonstrate peptic ulcer disease in man and animals. We evaluated the usefulness of (/sup 99m/Tc)Su for detecting various grades of esophagitis. (/sup 99m/Tc)Su adhered to the distal esophagus for up to 3 hr in five of six patients with esophageal ulcers but adhered to only two of nine with lesser degrees of esophagitis. No adherence was seen in five patients without esophagitis. Thus, (/sup 99m/Tc)Su may not be useful for detecting any but the most severe grade of esophagitis. Based on these results, we speculate that the previously documented beneficial effects of sucralfate on mild to moderate esophagitis may be due to other mechanisms besides adherence to the ulcerated mucosa.

  17. Interaction between fasudil hydrochloride and bovine serum albumin: spectroscopic study.

    PubMed

    Yu, Xianyong; Jiang, Bingfei; Xun, Caifang; Yao, Qing

    2016-06-01

    The interaction between fasudil hydrochloride (FSD) and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopy under imitated physiological conditions. The Stern-Volmer quenching model has been successfully applied and the results revealed that FSD could quench the intrinsic fluorescence of BSA effectively via static quenching. The binding constants and binding sites for the BSA-FSD system were evaluated. The corresponding thermodynamic parameters obtained at different temperatures indicated that hydrophobic force played a major role in the interaction of FSD and BSA. The distance between the donor (BSA) and the acceptor (FSD) was obtained according to fluorescence resonance energy transfer (FRET). Synchronous fluorescence spectroscopy and FT-IR spectra showed that the conformation of BSA was changed in the presence of FSD. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26554343

  18. Structural studies on serum albumins under green light irradiation.

    PubMed

    Comorosan, Sorin; Polosan, Silviu; Popescu, Irinel; Ionescu, Elena; Mitrica, Radu; Cristache, Ligia; State, Alina Elena

    2010-10-01

    This paper presents two new experimental results: the protective effect of green light (GL) on ultraviolet (UV) denaturation of proteins, and the effect of GL on protein macromolecular structures. The protective effect of GL was revealed on two serum albumins, bovine (BSA) and human (HSA), and recorded by electrophoresis, absorption, and circular dichroism spectra. The effect of GL irradiation on protein structure was recorded by using fluorescence spectroscopy and electrophoresis. These new effects were modeled by quantum-chemistry computation using Gaussian 03 W, leading to good fit between theoretical and experimental absorption and circular dichroism spectra. A mechanism for these phenomena is suggested, based on a double-photon absorption process. This nonlinear effect may lead to generation of long-lived Rydberg macromolecular systems, capable of long-range interactions. These newly suggested systems, with macroscopic quantum coherence behaviors, may block the UV denaturation processes. PMID:20473754

  19. Role of sensitization to mammalian serum albumin in allergic disease.

    PubMed

    Liccardi, Gennaro; Asero, Riccardo; D'Amato, Maria; D'Amato, Gennaro

    2011-10-01

    Serum albumin (SA) constitutes an intriguing puzzle that is involved in allergic sensitizations from different sources and induces different clinical manifestations. In this article, we describe the role of sensitization to SAs in inducing allergic diseases and the complex interactions and cross-reactivity between SA resulting from its presence in various mammalian tissues and fluids. SAs alone are an uncommon cause of allergic sensitization in airways, but these allergenic proteins likely play a significant role as cross-reacting allergens in individuals sensitized to several types of animal dander. SAs are a minor allergen in milk but a major allergen in meats. Recently, bovine SA has been added to the culture medium of spermatozoids used for artificial insemination. As a consequence, some case reports have shown that bovine SA may be a causative agent in severe anaphylaxis after standard intrauterine insemination or in vitro fertilization. PMID:21809117

  20. Stereoselective interaction of cinchona alkaloid isomers with bovine serum albumin.

    PubMed

    Liu, Yan; Chen, Mingmao; Jiang, Longguang; Song, Ling

    2015-08-15

    The dependence of the interaction between bovine serum albumin (BSA) and two cinchona alkaloids, quinine (QN) and quinidine (QD), on the absolute configuration of these stereoisomers has been comprehensively studied. The FTIR spectra showed that QN and QD interacted with both CO and C-N groups of BSA, resulting in changes to the secondary structure of the protein. Fluorescence quenching of BSA by the stereoisomers revealed lower efficiency for QD in quenching the Trp emission of BSA when compared to QN. Further analysis accurately described the different binding behaviors and recognition discrepancies of QN and QD towards BSA, which was reflected through binding affinities, driving forces, energy changes and conformational changes during the ligand-protein interactions. Synchronous fluorescence further proved that QD was farther from Trp and Tyr than that of QN. This work could provide basic data for clarifying the binding interaction, metabolism and distribution of cinchona alkaloid stereoisomers in vivo. PMID:25794736

  1. Anisotropic energy flow and allosteric ligand binding in albumin

    NASA Astrophysics Data System (ADS)

    Li, Guifeng; Magana, Donny; Dyer, R. Brian

    2014-01-01

    Allosteric interactions in proteins generally involve propagation of local structural changes through the protein to a remote site. Anisotropic energy transport is thought to couple the remote sites, but the nature of this process is poorly understood. Here, we report the relationship between energy flow through the structure of bovine serum albumin and allosteric interactions between remote ligand binding sites of the protein. Ultrafast infrared spectroscopy is used to probe the flow of energy through the protein backbone following excitation of a heater dye, a metalloporphyrin or malachite green, bound to different binding sites in the protein. We observe ballistic and anisotropic energy flow through the protein structure following input of thermal energy into the flexible ligand binding sites, without local heating of the rigid helix bundles that connect these sites. This efficient energy transport mechanism enables the allosteric propagation of binding energy through the connecting helix structures.

  2. Fluorescence quenching of bovine serum albumin by NNMB

    NASA Astrophysics Data System (ADS)

    Jayabharathi, J.; Jayamoorthy, K.; Thanikachalam, V.; Sathishkumar, R.

    2013-05-01

    A new type of fluorophore 2-(naphthalen-1-yl)-1-((naphthalen-1-yl)methyl)-1H-benzimidazole (NNMB) has been prepared and characterized by 1H NMR, 13C NMR, mass and IR spectral analysis. Absorption, fluorescence and synchronous fluorescence spectral studies have been made for the mutual interaction of NNMB with bovine serum albumin (BSA). Absorption spectroscopy proved the formation of a ground state BSA…NNMB complex. Fluorescence spectrum of BSA in the presence of NNMB clearly shows that NNMB acts as a quencher. Based on the theory of Forester's non-radiation energy transfer (FRET) binding distance has been deduced. The Stern-Volmer quenching constant (KSV), binding site number (n), apparent binding constant (KA) and corresponding thermodynamic parameters (ΔG, ΔH and ΔS) were determined.

  3. Heme-based catalytic properties of human serum albumin

    PubMed Central

    Ascenzi, P; di Masi, A; Fanali, G; Fasano, M

    2015-01-01

    Human serum albumin (HSA): (i) controls the plasma oncotic pressure, (ii) modulates fluid distribution between the body compartments, (iii) represents the depot and carrier of endogenous and exogenous compounds, (iv) increases the apparent solubility and lifetime of hydrophobic compounds, (v) affects pharmacokinetics of many drugs, (vi) inactivates toxic compounds, (vii) induces chemical modifications of some ligands, (viii) displays antioxidant properties, and (ix) shows enzymatic properties. Under physiological and pathological conditions, HSA has a pivotal role in heme scavenging transferring the metal-macrocycle from high- and low-density lipoproteins to hemopexin, thus acquiring globin-like reactivity. Here, the heme-based catalytic properties of HSA are reviewed and the structural bases of drug-dependent allosteric regulation are highlighted.

  4. Three-dimensional structure of human serum albumin

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.; He, Xiao-Min; Twigg, Pamela D.; Casale, Elena

    1991-01-01

    The binding locations to human serum albumin (HSA) of several drug molecules were determined at low resolution using crystallographic methods. The principal binding sites are located within subdomains IIA and IIIA. Preliminary studies suggest that an approach to increasing the in vivo efficacy of drugs which are rendered less effective or ineffective by virtue of their interaction with HSA, would be the use of competitive displacement in drug therapies and/or the development of a general inhibitor to the site within subdomain IIIA. These findings also suggest that the facilitated transfer of various ligands across organ/circulatory interfaces such as liver, kidney, and brain may be associated with binding to the IIIA subdomain.

  5. The effects of radioiodination and fluorescent labelling on albumin

    SciTech Connect

    Crandall, R.E.; Janatova, J.; Andrade, J.D.

    1981-01-01

    The preparation and characterization of fluorescamine -, fluorescein isothiocyanate (FITC) -, and radioiodine-labelled bovine serum albumin is critically evaluated. Electrophoretic mobility and ion-exchange chromatography, together with measures of degree of conjugation and sulfhydryl content, are used to assess the changes due to conjugation. Fluorescamine labelling results in drastic changes in chromatographic behavior and electrophoretic mobility. FITC labelling also results in significant changes in chromatographic and electrophoretic properties. Radioiodination leads to minor changes in chromatographic properties and oxydation of sulfhydryl groups, with little or no change in electrophoretic properties. All three labels have some degree of lability and show increased levels of free label with time, even after extensive initial purification. It is concluded that the two fluorescent labels and possibly the radioiodine labelling method used here are unsuitable for certain studies of BSA, such as its adsorption at solid-liquid interfaces.

  6. In situ observations of liquid-liquid phase separation in aqueous ZnSO4 solutions at temperatures up to 400 °C: Implications for Zn2+-SO42- association and evolution of submarine hydrothermal fluids

    NASA Astrophysics Data System (ADS)

    Wang, Xiaolin; Wan, Ye; Hu, Wenxuan; Chou, I.-Ming; Cao, Jian; Wang, Xiaoyu; Wang, Meng; Li, Zhen

    2016-05-01

    Liquid-liquid immiscibility is gaining recognition as an important process in hydrothermal fluid activity. However, studies of this complex process are relatively limited. We examined liquid-liquid immiscibility in aqueous ZnSO4 solutions at temperatures above ∼266.5 °C and at vapor-saturation pressures. The homogeneous aqueous ZnSO4 solution separated into ZnSO4-rich (L1) and ZnSO4-poor (L2) liquid phases coexisting with the vapor phase. The L1-L2 phase separation temperature decreased with increasing ZnSO4 concentration up to 1.0 mol/kg, and then increased at greater ZnSO4 concentrations, showing a typical lower critical solution temperature (LCST) of ∼266.5 °C. Gunningite (ZnSO4·H2O) precipitated in 2.0 mol/kg ZnSO4 solution at 360 °C. The L1-L2 phase separation resulted mainly from the strong Zn2+-SO42- association at high temperatures. The major results of this study are: (1) the discovery of the LCST in these systems, a macroscale property associated with polymeric mixtures; (2) analyses of the peak area ratios of the v1(SO42-) and OH stretching bands, which suggest that the sulfate concentration increases with increasing temperature in L1, especially above 375 °C; (3) a new Raman v1(SO42-) mode at ∼1005 cm-1 observed only in the L1 phase, whose fraction increases with increasing temperature; and (4) the shape of the OH Raman stretching band, which indicates that water molecules and solute interact much more strongly in L1 than in the coexisting L2 phase, suggesting that water molecules fit into the framework formed by various Zn2+-SO42- pairs and chain structures in L1. These results have potential implications for understanding transport and reduction of seawater-derived sulfate in submarine hydrothermal systems. The formation of an immiscible sulfate-rich liquid phase can favor the circulation of sulfate within mid-ocean ridge basalt because the sulfate-rich liquid density is higher than that of the coexisting fluid. The reduction of sulfate

  7. [Raman spectra of single human living erythrocyte with the effect of pH and serum albumin].

    PubMed

    Wu, Zheng-Jie; Wang, Cheng; Lin, Zheng-Chun; Jiao, Qing-Ze

    2014-05-01

    In the present work, a cell environment which mimicked the real body environment according to the concentration radio between serum albumin and hemoglobin was built, and the cell morphology, the membrane deformation capacity, and the structure of intracellular hemoglobin of single human living erythrocyte under the effect of pH and serum albumin were studied. It was found that at different suspension pH, the magnitude of variations in cell shape and membrane deformation capacity changes with the structural changes of the intracellular hemoglobin. At pH 4. 14, 4. 76 and 10. 18, the loss of helical structure for hemoglobin, exposing of the hydrophobic amino acid in the globin chains, and changing of the combination of heme and globin, would completely destroy the stability of hemoglobin's structure, which seriously changes RBC's morphology and membrane deformation capacity. While at pH 6. 51 and 7. 80, the Raman spectra of erythrocytes are found to have no such changes, indicating that the structure of intracellular hemoglobin was not varied, thus the cell morphology and membrane deformation capacity are quite close to the normal values. At pH 5. 49 and 8. 76, RBC's morphology and membrane deformation capacity have different degrees of variation, but the structure of intracellular hemoglobin has not changed, suggesting that the cell morphology and membrane deformation capacity may be reversible. The results suggest that in the suspension solution containing serum albumin, erythrocytes have better ability to regulate and control the variation of the extracellular pH. In summary, upon building an environment which contains the same concentration radio of serum albumin to hemoglobin in the blood, this work performed systematic studies on the effect of pH on human erythrocytes. It can not only help to solve the problems about the mechanism of the structural and functional changes of erythrocytes induced by environmental pH, but also elucidates the possible variation of

  8. The 29 September 2009 Samoa Islands Tsunami: Simulations Based on the First Focal Mechanism Solutions and Implications on Tsunami Early Warning Strategies

    NASA Astrophysics Data System (ADS)

    Tonini, Roberto; Armigliato, Alberto; Tinti, Stefano

    2011-06-01

    The tsunamigenic earthquake (Mw = 8.1) that occurred on 29 September 2009 at 17:48 UTC offshore of the Samoa archipelago east of the Tonga trench represents an example of the so-called "outer-rise" earthquakes. The areas most affected were the south coasts of Western and American Samoa, where almost 200 people were killed and run-up heights were measured in excess of 5 m at several locations along the coast. Moreover, tide gauge records showed a maximum peak-to-peak height of about 3.5 m near Pago Pago (American Samoa) and of 1.5 m offshore of Apia (Western Samoa). In this work, different fault models based on the focal mechanism solutions proposed by Global CMT and by USGS immediately after the 2009 Samoan earthquake are tested by comparing the near-field recorded signals (three offshore DART buoys and two coastal tide gauges) and the synthetic signals provided by the numerical simulations. The analysis points out that there are lights and shadows, in the sense that none of the computed tsunamis agrees satisfactorily with all the considered signals, although some of them reproduce some of the records quite well. This "partial agreement" and "partial disagreement" are analysed in the perspective of tsunami forecast and of Tsunami Early Warning System strategy.

  9. Influence of the Compatible Solute Ectoine on the Local Water Structure: Implications for the Binding of the Protein G5P to DNA.

    PubMed

    Hahn, Marc Benjamin; Solomun, Tihomir; Wellhausen, Robert; Hermann, Sabrina; Seitz, Harald; Meyer, Susann; Kunte, Hans-Jörg; Zeman, Johannes; Uhlig, Frank; Smiatek, Jens; Sturm, Heinz

    2015-12-10

    Microorganisms accumulate molar concentrations of compatible solutes like ectoine to prevent proteins from denaturation. Direct structural or spectroscopic information on the mechanism and about the hydration shell around ectoine are scarce. We combined surface plasmon resonance (SPR), confocal Raman spectroscopy, molecular dynamics simulations, and density functional theory (DFT) calculations to study the local hydration shell around ectoine and its influence on the binding of a gene-5-protein (G5P) to a single-stranded DNA (dT25). Due to the very high hygroscopicity of ectoine, it was possible to analyze the highly stable hydration shell by confocal Raman spectroscopy. Corresponding molecular dynamics simulation results revealed a significant change of the water dielectric constant in the presence of a high molar ectoine concentration as compared to pure water. The SPR data showed that the amount of protein bound to DNA decreases in the presence of ectoine, and hence, the protein-DNA dissociation constant increases in a concentration-dependent manner. Concomitantly, the Raman spectra in terms of the amide I region revealed large changes in the protein secondary structure. Our results indicate that ectoine strongly affects the molecular recognition between the protein and the oligonucleotide, which has important consequences for osmotic regulation mechanisms. PMID:26555929

  10. Effects of proteoliposome composition and draw solution types on separation performance of aquaporin-based proteoliposomes: implications for seawater desalination using aquaporin-based biomimetic membranes.

    PubMed

    Zhao, Yang; Vararattanavech, Ardcharaporn; Li, Xuesong; Hélixnielsen, Claus; Vissing, Thomas; Torres, Jaume; Wang, Rong; Fane, Anthony G; Tang, Chuyang Y

    2013-02-01

    Aquaporins are a large family of water transport proteins in cell membranes. Their high water permeability and solute rejection make them potential building blocks for high-performance biomimetic membranes for desalination. In the current study, proteoliposomes were prepared using AquaporinZ from Escherichia coli cells, and their separation properties were characterized by stopped-flow measurements. The current study systematically investigated the effect of proteoliposome composition (lipid type, protein-to-lipid ratio (PLR), and the addition of cholesterol) on water permeability and NaCl retention. Among the various lipids investigated, 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)-based proteoliposomes were found to have excellent osmotic water permeability and NaCl reflection coefficient values. Increasing the PLR of DOPC proteoliposomes up to 1:200 increased their osmotic water permeability. However, further increase in the PLR reduced the osmotic water permeability probably due to the occurrence of defects in the proteoliposomes, whereas the addition of cholesterol improved their osmotic water permeation likely due to defects sealing. The current study also investigated the effect of major dissolved ions in seawater (e.g., Mg(2+) and SO(4)(2-)) on the stability of proteoliposomes, and design criteria for aquaporin-based biomimetic membranes are proposed in the context of desalination. PMID:23311686

  11. The automatic use of capillary isoelectric focusing with whole column imaging detection for carbamazepine binding to human serum albumin.

    PubMed

    Maciążek-Jurczyk, Małgorzata; Pawliszyn, Janusz

    2016-08-01

    The binding of the anticonvulsant drug carbamazepine (CBZ) to human serum albumin, both without (dHSA) and in the presence of fatty acids (HSA) was studied in real time by capillary isoelectric focusing with whole column imaging detection (cIEF-WCID). Reaction mixtures at different CBZ:HSA and CBZ:dHSA molar ratios (0:1/25:1) were prepared in phosphate buffer saline (PBS) solution at a physiological pH (7.4), and incubated for 0-72h at 37°C in a water bath. Application of the cIEF-WCID method allowed for observations on the impact of increasing CBZ:serum albumin molar ratios on isoelectric point (pI) shifts, as well as changes in peak area and absorbance, which serve as evidence of structural alterations occurring in the protein in the presence of CBZ. The obtained cIEF-WCID results indicated that the dynamic process of complex formation is not dependent on incubation time. The presented work allowed for recognition of different types of interactions, as well as for the calculation of association constants that demonstrate the stability of the complex. This study was also designed to examine the possible impact of fatty acids (FAs) on protein stability and drug delivery in blood. PMID:26809616

  12. Study on the interaction between isoniazid and bovine serum albumin by fluorescence spectroscopy: the effect of dimethylsulfoxide.

    PubMed

    Markarian, Shiraz A; Aznauryan, Mikayel G

    2012-07-01

    The investigation of the binding between isoniazid (or isonicotinic acid hydrazide, INH) and serum albumin is of crucial importance to reveal the reason of resistant Mycobacterium tuberculosis strains towards INH and to increase the anti-tuberculous activity of INH. The interaction between INH and bovine serum albumin (BSA) was studied by fluorescence, UV and FT-IR spectroscopy methods. The analysis of the emission quenching at different temperatures revealed that the quenching mechanism corresponds to a static process and, as consequence; a complex INH-BSA is formed. The modified Stern-Volmer quenching constant K (a) and the corresponding thermodynamic parameters ΔH, ΔG and ΔS were calculated. The distance, r, between donor (BSA) and acceptor (INH) was calculated to be 2.14 nm based on Förster's non-radiative energy transfer theory (FRET). The results obtained on the basis of fluorescence study of BSA solutions at the presence of dimethylsulfoxide (DMSO) were discussed in terms of the hydration properties and competitive intermolecular interactions between BSA and solvent components. The dependence of binding constant on the concentration of added DMSO as a solvent component showed non monotonous behavior. The conformational changes of BSA and its secondary structure alterations at the presence of INH were revealed. PMID:22327779

  13. Thymosin α1 Interacts with Exposed Phosphatidylserine in Membrane Models and in Cells and Uses Serum Albumin as a Carrier.

    PubMed

    Mandaliti, Walter; Nepravishta, Ridvan; Sinibaldi Vallebona, Paola; Pica, Francesca; Garaci, Enrico; Paci, Maurizio

    2016-03-15

    Thymosin α1 is a peptidic hormone with pleiotropic activity and is used in the therapy of several diseases. It is unstructured in water solution and interacts with negative regions of vesicles by assuming two tracts of helical conformation with a structural break between them. This study reports on Thymosin α1's interaction with mixed phospholipids phosphatidylcholine and phosphatidylserine, the negative component of the membranes, by ¹H and natural abundance ¹⁵N nuclear magnetic resonance (NMR). The results indicate that interaction occurs when the membrane is negatively charged by exposing phosphatidylserine. Moreover, the direct interaction of Thymosin α1 with K562 cells with an overexposure of phosphatidylserine as a consequence of resveratrol-induced apoptosis was conducted. Thymosin α1's interaction with human serum albumin was also investigated by NMR spectroscopy. Steady-state saturation transfer, transfer nuclear Overhauser effect spectroscopy, and diffusion-ordered spectroscopy methodologies all reveal that the C-terminal region of Thymosin α1 is involved in the interaction with serum albumin. These results may shed more light on Thymosin α1's mechanism of action by its insertion in negative regions of membranes due to the exposure of phosphatidylserine. Once Thymosin α1's N-terminus has been inserted into the membrane, the rest may interact with nearby proteins and/or receptors acting as effectors and causing a biological signaling cascade, thus exerting thymosin α1's pleiotropy. PMID:26909491

  14. Physicochemical studies on the interaction of serum albumin with pulmonary surfactant extract in films and bulk bilayer phase.

    PubMed

    Nag, Kaushik; Vidyashankar, Sangeetha; Devraj, Ravi; Fritzen Garcia, Mauricia; Panda, Amiya K

    2010-12-15

    Functionality, structure and composition of the adsorbed films of bovine lipid extract surfactant (BLES), in the absence and presence of bovine serum albumin (BSA), at the air-buffer interface was characterized through surface tension, atomic force microscopy and time of flight secondary ion mass spectrometric methods. Gel and fluid domains of BLES films were found to be altered significantly in the presence of BSA. Differential scanning calorimetric studies on BLES dispersions in presence of BSA revealed that the perturbations of the lipid bilayer structures were significant only at higher amount of BSA. FTIR studies on the BLES dispersions in buffer solution revealed that BSA could affect the lipid head-group hydrations in bilayer as well as the methylene and methyl vibration modes of fatty acyl chains of the phospholipids present in BLES. Serum albumin could perturb the film structure at pathophysiological concentration while higher amount of BSA was required in perturbing the bilayer structures. The studies suggest a connected perturbed bilayer to monolayer transition model for surfactant inactivation at the alveolar-air interface in dysfunctional surfactants. PMID:20850129

  15. Highly sensitive detection of bovine serum albumin based on the aggregation of triangular silver nanoplates

    NASA Astrophysics Data System (ADS)

    Zhang, Ling Ling; Ma, Fang Fang; Kuang, Yang Fang; Cheng, Shu; Long, Yun Fei; Xiao, Qiu Guo

    2016-02-01

    A simple, fast and highly sensitive spectrophotometric method for the determination of bovine serum albumin (BSA) has been developed based on the interactions between triangular silver nanoplates (TAgNPs) and BSA in the presence of Britton-Robison buffer solution (BR). Particularly, the wavelength of absorption maximum (λmax) of TAgNPs is red shifted in the presence of BSA together with Britton-Robinson buffer solution (BR, pH = 2.56), and the color of the solution changed from blue to light blue. This may be due to the interactions between BSA molecules on the surface of TAgNPs through electrostatic forces, hydrogen bonds, hydrophobic effects and van der Waals forces at pH 2.56, which leads to the aggregation of TAgNPs. The determination of BSA was achieved by measuring the change of λmax corresponding to localized surface plasmon resonance (LSPR) from UV-visible spectrophotometry. It was found that the shift value in the wavelength of absorption maximum (Δλ, the difference in absorption maxima of the TAgNPs/BSA/BR mixture and the TAgNPs/BR mixture) was proportionate to the concentration of BSA in the range of 1.0 ng mL- 1 to 100.0 ng mL- 1 with the correlation coefficient of r = 0.9969. The detection limit (3 σ/k) for BSA was found to be as low as 0.5 ng mL- 1.

  16. Viscous cosolvent effect on the ultrasonic absorption of bovine serum albumin.

    PubMed

    Almagor, A; Yedgar, S; Gavish, B

    1992-02-01

    Protein-ligand binding and enzyme activity have been shown to be regulated by solvent viscosity, induced by the addition of viscous cosolvents. This was indirectly interpreted as an effect on protein dynamics. However, viscous cosolvents might affect dynamic, e.g., viscosity, as well as thermodynamic properties of the solution, e.g., activity of solution components. This work was undertaken to examine the effect of viscous cosolvent on the structural dynamics of proteins and its correlation with dynamic and thermodynamic solution properties. For this purpose we studied the effect of viscous cosolvent on the specific ultrasonic absorption, delta mu, of bovine serum albumin, at pH = 7.0 and at 21 degrees C, and frequency range of 3-4 MHz. Ultrasonic absorption (UA) directly probes protein dynamics related to energy dissipation processes. It was found that the addition of sucrose, glycerol, or ethylene glycol increased the BSA delta mu. This increase correlates well with the solvent viscosity, but not with the cosolvent mass concentration, activity of the solvent components, dielectric constant, or the hydration of charged groups. On the grounds of these results and previously reported findings, as well as theoretical considerations, we propose the following mechanism for the solvent viscosity effect on the protein structural fluctuations, reflected in the UA: increased solvent viscosity alters the frequency spectrum of the polypeptide chain movements; attenuating the fast (small amplitude) movements, and enhancing the slow (large amplitude) ones. This modulates the interaction strength between the polypeptide and water species that "lubricates" the chain's movements, leading to larger protein-volume fluctuation and higher ultrasonic absorption. This study demonstrates that solvent viscosity is a regulator of protein structural fluctuations. PMID:1547333

  17. 9 CFR 95.16 - Blood meal, blood albumin, intestines, and other animal byproducts for industrial use...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Blood meal, blood albumin, intestines... Blood meal, blood albumin, intestines, and other animal byproducts for industrial use; importations permitted subject to restrictions. Blood meal, blood albumin, bone meal, intestines, or other...

  18. 9 CFR 95.16 - Blood meal, blood albumin, intestines, and other animal byproducts for industrial use...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Blood meal, blood albumin, intestines... Blood meal, blood albumin, intestines, and other animal byproducts for industrial use; importations permitted subject to restrictions. Blood meal, blood albumin, bone meal, intestines, or other...

  19. 9 CFR 95.16 - Blood meal, blood albumin, intestines, and other animal byproducts for industrial use...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Blood meal, blood albumin, intestines... Blood meal, blood albumin, intestines, and other animal byproducts for industrial use; importations permitted subject to restrictions. Blood meal, blood albumin, bone meal, intestines, or other...

  20. 9 CFR 95.16 - Blood meal, blood albumin, intestines, and other animal byproducts for industrial use...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Blood meal, blood albumin, intestines... Blood meal, blood albumin, intestines, and other animal byproducts for industrial use; importations permitted subject to restrictions. Blood meal, blood albumin, bone meal, intestines, or other...

  1. Comparison of Calcium Phosphate and Zinc Oxide Nanoparticles as Dermal Penetration Enhancers for Albumin

    PubMed Central

    Shokri, Narges; Javar, H. A.

    2015-01-01

    Dermal drug delivery is highly preferred by patients due to its several advantages. Protein therapeutics have attracted huge attention recently. Since dermal delivery of proteins encounter problems, in this investigation, zinc oxide nanoparticles and calcium phosphate nanoparticles were compared as enhancers for dermal permeation of albumin. Albumin was applied simultaneously with zinc oxide nanoparticles or calcium phosphate nanoparticles on pieces of mouse skin. Skin permeation of albumin over time was determined using a diffusion cell. Skin distribution of the nanoparticles and albumin over time was determined by optical and fluorescence microscopy. Zinc oxide nanoparticles and calcium phosphate nanoparticles acted as enhancers for skin permeation of albumin. Cumulative permeated albumin in presence of zinc oxide nanoparticles after 0, 0.5, 1, 1.5 and 2 h, were 0±0, 11.7±3.3, 21.1±3.5, 40.2±3.6 and 40.2±3.6 mg, respectively and in presence of calcium phosphate nanoparticles were 0±0, 20.9±7.4, 33.8±5.5, 33.8±3.7 and 33.8±3.7 mg, respectively. After 0.5 h, little amount of albumin was permeated in presence of every kind of the nanoparticles. After 0.5 or 1 h, the permeated albumin in presence of calcium phosphate nanoparticles was more than that in presence of zinc oxide nanoparticles and after 1.5 h the permeated albumin in presence of zinc oxide nanoparticles was more than that in presence of calcium phosphate nanoparticles. Images of skin distribution of the two nanoparticles over time, were somewhat different and distribution of albumin correlated with the distribution of the nanoparticles alone. The profiles of albumin permeation (in presence of each of the nanoparticles) versus time was delayed and linear for both nanoparticles while the slope for calcium phosphate nanoparticles was higher than zinc oxide nanoparticles. The enhancer effect of zinc oxide nanoparticles was stronger while the enhancer effect of calcium phosphate nanoparticles was

  2. Comparison of Calcium Phosphate and Zinc Oxide Nanoparticles as Dermal Penetration Enhancers for Albumin.

    PubMed

    Shokri, Narges; Javar, H A

    2015-01-01

    Dermal drug delivery is highly preferred by patients due to its several advantages. Protein therapeutics have attracted huge attention recently. Since dermal delivery of proteins encounter problems, in this investigation, zinc oxide nanoparticles and calcium phosphate nanoparticles were compared as enhancers for dermal permeation of albumin. Albumin was applied simultaneously with zinc oxide nanoparticles or calcium phosphate nanoparticles on pieces of mouse skin. Skin permeation of albumin over time was determined using a diffusion cell. Skin distribution of the nanoparticles and albumin over time was determined by optical and fluorescence microscopy. Zinc oxide nanoparticles and calcium phosphate nanoparticles acted as enhancers for skin permeation of albumin. Cumulative permeated albumin in presence of zinc oxide nanoparticles after 0, 0.5, 1, 1.5 and 2 h, were 0±0, 11.7±3.3, 21.1±3.5, 40.2±3.6 and 40.2±3.6 mg, respectively and in presence of calcium phosphate nanoparticles were 0±0, 20.9±7.4, 33.8±5.5, 33.8±3.7 and 33.8±3.7 mg, respectively. After 0.5 h, little amount of albumin was permeated in presence of every kind of the nanoparticles. After 0.5 or 1 h, the permeated albumin in presence of calcium phosphate nanoparticles was more than that in presence of zinc oxide nanoparticles and after 1.5 h the permeated albumin in presence of zinc oxide nanoparticles was more than that in presence of calcium phosphate nanoparticles. Images of skin distribution of the two nanoparticles over time, were somewhat different and distribution of albumin correlated with the distribution of the nanoparticles alone. The profiles of albumin permeation (in presence of each of the nanoparticles) versus time was delayed and linear for both nanoparticles while the slope for calcium phosphate nanoparticles was higher than zinc oxide nanoparticles. The enhancer effect of zinc oxide nanoparticles was stronger while the enhancer effect of calcium phosphate nanoparticles was

  3. Thermodynamics of aqueous solutes at high temperatures and pressures: Application of the hydration theory and implications for fluid-mediated mass transfer

    NASA Astrophysics Data System (ADS)

    Sulak, M.; Dolejs, D.

    2012-04-01

    Magmatic activity and prograde devolatilization of subducting or underplating lithologies release large quantities of aqueous fluids that act as mass and heat transfer agents in the planetary interiors. Understanding of mineral-melt-fluid interactions is essential for evaluating the effects of fluid-mediated mass transport in subduction zones, collisional orogens as well as in igneous provinces. The thermodynamic properties of aqueous species were frequently described by the Helgeson-Kirkham-Flowers equation of state [1] but its utility is limited by inavailability of the solvent dielectric properties at high pressures and temperatures, and by decoupling of species-solvent mechanical and electrostatic interactions that cannot be separated within the Born theory. Systematic description of the hydration process in a Born-Haber cycle leads to the following thermochemical contributions: (i) thermodynamic properties of an unhydrated species, (ii) the pressure-volume work required to create a cavity within the solvent to accommodate the species, described by the scaled particle theory, (iii) entropic contribution related to changes in the solute's and the solvent's kinetic degrees of freedom, and (iv) contribution from the solute-solvent molecular interactions and corresponding rearrangement of the solvent molecules to form the hydration shell. Application of the spatial correlation functions [2, 3] results in apparent Gibbs energy of aqueous species, ΔaGi = a + bT + cTlnT + dP + eTlnρ + fTρlnρ, where athrough f represent constants related to standard thermodynamic properties of aqueous species (ΔfH, S, V, cP) and to solvent volumetric properties at 298.15 K and 1 bar (ρ, α, β etc.). In phase equilibrium calculations, the number of required parameters often reduces to four (c = f = 0) while noting that H2O density as the only solvent-related property is accurately known to extreme temperatures and pressures. The equation of state parameters were calibrated for 30

  4. Effect of preservative solutions on preservation of Calliphora augur and Lucilia cuprina larvae (Diptera: Calliphoridae) with implications for post-mortem interval estimates.

    PubMed

    Day, Donnah M; Wallman, James F

    2008-07-18

    A major role of forensic entomology is to estimate the post-mortem interval. An entomologist's estimate of post-mortem interval is based on a series of generally valid assumptions, error in any of which can alter the accuracy of an estimate. The initial process of collecting and preserving maggots can itself lead to error, as can the method of killing and preservation. Since circumstances exist where it is not possible to rear maggots, methods of killing and preservation can be vital to preserving the integrity of entomological evidence. In this study, a number of preservation techniques used at crime scenes and in mortuaries were examined, and their effect on feeding third-instar larvae of Calliphora augur and Lucilia cuprina evaluated. The preservatives used were 70, 75, 80, 90 and 100% EtOH, Kahle's solution and 10% formalin. Each treatment was replicated three times. The effect of handling on first- and second-instar, feeding and post-feeding third-instar larvae of C. augur was also examined and compared to unhandled controls. Finally, the effects of preservatives were noted when larvae of C. augur and L. cuprina were placed into preservatives alive. It was found that continued handling is detrimental to specimens because preservative evaporates from both the vial and the specimens. No single preservative type was found to be entirely suitable for both species if DNA retrieval is desired. Specimens placed into most preservatives alive exhibited adverse colour changes, desiccation, sunkeness and agglomeration. It is concluded that the reaction to preservative type might be species specific and that different instars of the same species might also react differently. PMID:18514451

  5. Structures and solution properties of two novel periplasmic sensor domains with c-type heme from chemotaxis proteins of Geobacter sulfurreducens : implications for signal transduction.

    SciTech Connect

    Pokkuluri, P. R.; Pessanha, M.; Londer, Y. Y.; Wood, S. J.; Duke, N. E. C.; Wilton, R.; Catarino, T.; Salgueiro, C. A.; Schiffer, M.; Biosciences Division; Univ.Nova de Lisboa; Insti. de Tecnologia Quimica e Biologica

    2008-04-11

    Periplasmic sensor domains from two methyl-accepting chemotaxis proteins from Geobacter sulfurreducens (encoded by genes GSU0935 and GSU0582) were expressed in Escherichia coli. The sensor domains were isolated, purified, characterized in solution, and their crystal structures were determined. In the crystal, both sensor domains form swapped dimers and show a PAS-type fold. The swapped segment consists of two helices of about 45 residues at the N terminus with the hemes located between the two monomers. In the case of the GSU0582 sensor, the dimer contains a crystallographic 2-fold symmetry and the heme is coordinated by an axial His and a water molecule. In the case of the GSU0935 sensor, the crystals contain a non-crystallographic dimer, and surprisingly, the coordination of the heme in each monomer is different; monomer A heme has His-Met ligation and monomer B heme has His-water ligation as found in the GSU0582 sensor. The structures of these sensor domains are the first structures of PAS domains containing covalently bound heme. Optical absorption, electron paramagnetic resonance and NMR spectroscopy have revealed that the heme groups of both sensor domains are high-spin and low-spin in the oxidized and reduced forms, respectively, and that the spin-state interconversion involves a heme axial ligand replacement. Both sensor domains bind NO in their ferric and ferrous forms but bind CO only in the reduced form. The binding of both NO and CO occurs via an axial ligand exchange process, and is fully reversible. The reduction potentials of the sensor domains differ by 95 mV (-156 mV and -251 mV for sensors GSU0582 and GSU0935, respectively). The swapped dimerization of these sensor domains and redox-linked ligand switch might be related to the mechanism of signal transduction by these chemotaxis proteins.

  6. Solution NMR characterization of magnetic/electronic properties of azide and cyanide-inhibited substrate complexes of human heme oxygenase: implications for steric ligand tilt.

    PubMed

    Peng, Dungeng; Ogura, Hiroshi; Ma, Li-Hua; Evans, John P; de Montellano, Paul R Ortiz; La Mar, Gerd N

    2013-04-01

    Solution 2D (1)H NMR was carried out on the azide-ligated substrate complex of human heme oxygenase, hHO, to provide information on the active site molecular structure, chromophore electronic/magnetic properties, and the distal H-bond network linked to the exogenous ligand by catalytically relevant oriented water molecules. While 2D NMR exhibited very similar patterns of two-dimensional nuclear Overhauser spectroscopy cross peaks of residues with substrate and among residues as the previously characterized cyanide complex, significant, broadly distributed chemical shift differences were observed for both labile and non-labile protons. The anisotropy and orientation of the paramagnetic susceptibility tensor, χ, were determined for both the azide and cyanide complexes. The most significant difference observed is the tilt of the major magnetic axes from the heme normal, which is only half as large for the azide than cyanide ligand, with each ligand tilted toward the catalytically cleaved α-meso position. The difference in chemical shifts is quantitatively correlated with differences in dipolar shifts in the respective complexes for all but the distal helix. The necessity of considering dipolar shifts, and hence determination of the orientation/anisotropy of χ, in comparing chemical shifts involving paramagnetic complexes, is emphasized. The analysis shows that the H-bond network cannot detect significant differences in H-bond acceptor properties of cyanide versus azide ligands. Lastly, significant retardation of distal helix labile proton exchange upon replacing cyanide with azide indicates that the dynamic stability of the distal helix is increased upon decreasing the steric interaction of the ligand with the distal helix. PMID:23391487

  7. Analbuminemia: three cases resulting from different point mutations in the albumin gene.

    PubMed Central

    Watkins, S; Madison, J; Galliano, M; Minchiotti, L; Putnam, F W

    1994-01-01

    Analbuminemia is a very rare recessive disorder in which subjects have little or no circulating albumin, although albumin is normally the most abundant plasma protein and has many functions. Analbuminemia is caused by a variety of mutations in the albumin gene and is exhibited only by subjects homozygous for the defect. Previously the mutation had been identified at the molecular level in only two human cases; in one case it resulted from an exon-splicing defect, and in the other case it was caused by a nucleotide insertion that caused a frameshift and premature stop codon. In this investigation we identified the mutations in three unrelated subjects from different countries. In each instance a single-nucleotide mutation produced a stop codon, but the mutations occurred at three different sites: (i) in an Italian male a C-->T transition at nt 2368 in the genomic sequence of albumin, (ii) a C-->T transition at nt 4446 for an American female, and (iii) a G-->A transition at nt 7708 in a Canadian male. The size of the albumin fragment that might have been produced for the three cases varied from 31- to 213-amino acid residues, but no evidence for a circulating albumin fragment was obtained. The paradox is that analbuminemia is extremely rare (frequency < 1 x 10(6)); yet the virtual absence of albumin is tolerable despite its multiple functions. Images PMID:7937781

  8. Depletion of the highly abundant protein albumin from human plasma using the Gradiflow.

    PubMed

    Rothemund, Deborah L; Locke, Vicki L; Liew, Audrey; Thomas, Theresa M; Wasinger, Valerie; Rylatt, Dennis B

    2003-03-01

    Analysis of complex protein samples by two-dimensional electrophoresis (2-DE) is often more difficult in the presence of a few predominant proteins. In plasma, proteins such as albumin mask proteins of lower abundance, as well as significantly limiting the amount of protein that can be loaded onto the immobilized pH gradient strip. In this paper the Gradiflow, a preparative electrophoresis system, has been used to deplete human plasma of the highly abundant protein albumin under native and denatured conditions. A three step protocol incorporating a charge separation to collect proteins with an isoelectric point greater than albumin and two size separations to isolate proteins larger and smaller than albumin, was used. When the albumin depleted fractions were analysed on pH 3-10 2-DE gels, proteins that were masked by albumin were revealed and proteins not seen in the unfractionated plasma sample were visualised. Matrix-assisted laser desorption/ionisation-time of flight mass spectrometry analysis confirmed the identification of the protein that lies beneath albumin to be C4B-binding protein alpha chain. The liquid fractions from the Gradiflow separations were also analysed by liquid chromatography-tandem mass spectrometry to confirm the proteins were separated according to their size and charge mobility in an electric field. PMID:12627381

  9. In vivo photoacoustic molecular imaging of the distribution of serum albumin in rat burned skin.

    PubMed

    Tsunoi, Yasuyuki; Sato, Shunichi; Kawauchi, Satoko; Ashida, Hiroshi; Saitoh, Daizoh; Terakawa, Mitsuhiro

    2013-11-01

    Information on the state of edema is important for treating severe burn injuries, but a method for noninvasive real-time quantitative diagnosis of edema is not available. Thus, in vivo spatiotemporal characteristics of serum albumin, which would behave differently from water in burned tissue, are not fully understood. In this study, we used a photoacoustic (PA) imaging method to visualize depth distribution of albumin in a rat deep burn model, for which Evans blue was used as a nontoxic molecular probe. Water content in the tissue and urine volume were also measured for reference. We performed PA imaging of albumin in three regions in the rats, burn and nonburn regions and their boundary, and the imaging showed that albumin started to leak out of the vessels in the boundary and diffused within the burned tissue. Diffusion of albumin into the nonburn region, where water content was increased, was limited. In the burn and boundary regions, albumin-originating PA signal increased in two phases: immediately after making burns and from 24 to 72 h after burn. The second increase is attributable to the selective return of water to the vessels, resulting in increased concentration of albumin in extravascular tissue. PMID:23597848

  10. Vapor conjugation of toluene diisocyanate to specific lysines of human albumin

    PubMed Central

    Hettick, Justin M.; Siegel, Paul D.; Green, Brett J.; Liu, Jian; Wisnewski, Adam V.

    2012-01-01

    Exposure to toluene diisocyanate (TDI), an industrially important crosslinking agent used in the production of polyurethane products, can cause asthma in sensitive workers. Albumin has been identified as a major reaction target for TDI in vivo, and TDI–albumin reaction products have been proposed to serve as exposure biomarkers and to act as asthmagens, yet they remain incompletely characterized. In the current study, we used a multiplexed tandem mass spectrometry (MS/MS) approach to identify the sites of albumin conjugation by TDI vapors, modeling the air/liquid interface of the lung. Vapor phase TDI was found to react with human albumin in a dose-dependent manner, with up to 18 potential sites of conjugation, the most susceptible being Lys351 and the dilysine site Lys413–414. Sites of vapor TDI conjugation to albumin were quantitatively limited compared with those recently described for liquid phase TDI, especially in domains IIA and IIIB of albumin. We hypothesize that the orientation of albumin at the air/liquid interface plays an important role in vapor TDI conjugation and, thus, could influence biological responses to exposure and the development of in vitro assays for exposure and immune sensitivity. PMID:22206939

  11. Synaptic plasticity in area CA1 of rat hippocampal slices following intraventricular application of albumin.

    PubMed

    Salar, Seda; Lapilover, Ezequiel; Müller, Julia; Hollnagel, Jan-Oliver; Lippmann, Kristina; Friedman, Alon; Heinemann, Uwe

    2016-07-01

    Epileptogenesis following insults to the brain may be triggered by a dysfunctional blood-brain barrier (BBB) associated with albumin extravasation and activation of astrocytes. Using ex vivo recordings from the BBB-disrupted hippocampus after neocortical photothrombotic stroke, we previously demonstrated abnormal activity-dependent accumulation of extracellular potassium with facilitated generation of seizure like events and spreading depolarizations. Similar changes could be observed after intracerebroventricular (icv) application of albumin. We hypothesized that alterations in extracellular potassium and glutamate homeostasis might lead to alterations in synaptic interactions. We therefore assessed the effects of icv albumin on homo- and heterosynaptic plasticity in hippocampal CA1, 24h after a single injection or 7days after continuous infusion of icv albumin. We demonstrate alterations in both homo- and heterosynaptic plasticity compared to control conditions in ex vivo slice studies. Albumin-treated tissue reveals (1) reduced long-term depression following low-frequency stimulation; (2) increased long-term potentiation of population spikes in response to 20Hz stimulation; (3) potentiated responses to Schaffer collateral stimulation following high-frequency stimulation of the direct cortical input and low-frequency stimulation of alveus and finally, (4) TGFβ receptor II (TGFβR-II) involvement in albumin-induced homosynaptic plasticity changes. We conclude that albumin-induced network hyperexcitability is associated with abnormal homo- and heterosynaptic plasticity that could partly be reversed by interference with TGFβR-II-mediated signaling and therefore it might be an important factor in the process of epileptogenesis. PMID:26972679

  12. Enhancing effect of albumin hydrolysate on ethanol production employing Saccharomyces sake

    SciTech Connect

    Shin, C.S.; Song, J.Y.; Ryu, O.H. ); Wang, S.S. . Dept. of Chemical and Biochemical Engineering)

    1995-03-05

    The enhancing effect of albumin hydrolysate on ethanol production was investigated in ethanol fermentations using Saccharomyces sake. In batchwise ethanol production, addition of supplemental albumin hydrolysate and phosphatidylcholine, or albumin hydrolysate alone, brought about a more than 60% increase in final ethanol concentration (148 or 144 g/L compared with 88 g/L with no supplementation [control] after 72h). The effect of the supplements is believed to be due to an enhanced alcohol tolerance of cells grown in media containing the supplements. Cells grown in media containing albumin hydrolysate were enriched in phenylalanine, tyrosine,d and methionine in their plasma membranes. All three amino acids were also present in considerable amounts in the albumin hydrolysate. This fact suggests that the three amino acids, which are present in albumin hydrolysate, are incorporated into the plasma membranes of cells. Under ethanol production conditions in which only one amino acid among the components of albumin hydrolysate was excluded, namely phenylalanine, tyrosine, or methionine, significant reductions in ethanol production resulted.

  13. Structure-based mutagenesis reveals the albumin-binding site of the neonatal Fc receptor

    PubMed Central

    Andersen, Jan Terje; Dalhus, Bjørn; Cameron, Jason; Daba, Muluneh Bekele; Plumridge, Andrew; Evans, Leslie; Brennan, Stephan O.; Gunnarsen, Kristin Støen; Bjørås, Magnar; Sleep, Darrell; Sandlie, Inger

    2012-01-01

    Albumin is the most abundant protein in blood where it has a pivotal role as a transporter of fatty acids and drugs. Like IgG, albumin has long serum half-life, protected from degradation by pH-dependent recycling mediated by interaction with the neonatal Fc receptor, FcRn. Although the FcRn interaction with IgG is well characterized at the atomic level, its interaction with albumin is not. Here we present structure-based modelling of the FcRn–albumin complex, supported by binding analysis of site-specific mutants, providing mechanistic evidence for the presence of pH-sensitive ionic networks at the interaction interface. These networks involve conserved histidines in both FcRn and albumin domain III. Histidines also contribute to intramolecular interactions that stabilize the otherwise flexible loops at both the interacting surfaces. Molecular details of the FcRn–albumin complex may guide the development of novel albumin variants with altered serum half-life as carriers of drugs. PMID:22215085

  14. Modulation of albumin-induced endoplasmic reticulum stress in renal proximal tubule cells by upregulation of mapk phosphatase-1.

    PubMed

    Gorostizaga, Alejandra; Mori Sequeiros García, Maria Mercedes; Acquier, Andrea; Gomez, Natalia V; Maloberti, Paula M; Mendez, Carlos F; Paz, Cristina

    2013-10-25

    High amounts of albumin in urine cause tubulointerstitial damage that leads to a rapid deterioration of the renal function. Albumin exerts its injurious effects on renal cells through a process named endoplasmic reticulum (ER) stress due to the accumulation of unfolded proteins in the ER lumen. In addition, albumin promotes phosphorylation and consequent activation of MAPKs such as ERK1/2. Since ERK1/2 activation promoted by albumin is a transient event, the aims of the present work were to identify the phosphatase involved in their dephosphorylation in albumin-exposed cells and to analyze the putative regulation of this phosphatase by albumin. We also sought to determine the role played by the phospho/dephosphorylation of ERK1/2 in the cellular response to albumin-induced ER stress. MAP kinase phosphatase-1, MKP-1, is a nuclear enzyme involved in rapid MAPK dephosphorylation. Here we present evidence supporting the notion that this phosphatase is responsible for ERK1/2 dephosphorylation after albumin exposure in OK cells. Moreover, we demonstrate that exposure of OK cells to albumin transiently increases MKP-1 protein levels. The increase was evident after 15 min of exposure, peaked at 1 h (6-fold) and declined thereafter. In cells overexpressing flag-MKP-1, albumin caused the accumulation of this chimera, promoting MKP-1 stabilization by a posttranslational mechanism. Albumin also promoted a transient increase in MKP-1 mRNA levels (3-fold at 1 h) through the activation of gene transcription. In addition, we also show that albumin increased mRNA levels of GRP78, a key marker of ER stress, through an ERK-dependent pathway. In line with this finding, our studies demonstrate that flag-MKP-1 overexpression blunted albumin-induced GRP78 upregulation. Thus, our work demonstrates that albumin overload not only triggers MAPK activation but also tightly upregulates MKP-1 expression, which might modulate ER stress response to albumin overload. PMID:23994741

  15. [Cooperative interaction of serum albumin with quaternized poly-4-vinyl pyridine and structure of the complexes].

    PubMed

    Kabanov, V A; Evdakov, V P; Mustafaev, M I; Antipina, A D

    1977-01-01

    Interaction of bovine serum albumin (BSA) with quaternized poly-4-vinyl pyridine (PE) in aqueous solutions at pH 7 was studied. It was shown that in a wide range of the ratios of the components (nBSA/nPE) soluble stable cooperative complexes were formed. At the same time a certain critical content of the protein exists at which the system loses its homogeneity. Complex formation is not accompanied by protein denaturation. At smaller nBSA/nPE ratios non-homogeneous distribution of protein globulas among polyelectrolite macromolecules was found; this corresponded to the "all or none" principle. Using ultracentrifugation technique viscosimetric measurements and electron microscopy it was shown that the soluble complexes exist in the form of rode-like particles consisting of protein globules stabilized by polycation chains. Such particle can be considered as a model of nucleoprotein complex. At certain crytical nBSA/nPE rations the rod-like particles aggregate with additional number of BSA-molecules and form more complicate soluble and insoluble cooperative complexes. Possible structural models of the complexes described were suggested and the thermodinamic and kinetic cryteria of their self-assembly were discussed. PMID:37435

  16. Decoration of heparin and bovine serum albumin on polysulfone membrane assisted via polydopamine strategy for hemodialysis.

    PubMed

    Xie, Bingwu; Zhang, Ranran; Zhang, Huan; Xu, Anxiu; Deng, Yi; Lv, Yalin; Deng, Feng; Wei, Shicheng

    2016-06-01

    Renal failure brings about abnormality of waste and toxins and deposition in the body. In clinic, the waste and toxins in vitro are eliminated by hemodialysis device with polysulfone (PSF) porous membranes. In the work, decoration of heparin (Hep) and bovine serum albumin (BSA) on PSF membranes would be beneficial to improve the hemocompatibility and reduce the anaphylatoxin formation during hemodialysis. The PSF porous membranes are surface-modified by simply dipping them into dopamine aqueous solution for 8 h. Then, Hep and BSA are immobilized covalently onto the resultant membrane. Attenuated total reflectance Fourier transform infrared spectra (ATR-FTIR) confirms that Hep and BSA are successfully introduced onto the surface of PSF membranes. Scanning electronic microscopy (SEM) and atomic force microscopy (AFM) display the changes of surface morphologies after modification. The result of water contact angle measurement shows that the hydrophilicity of PSF membranes is remarkably improved after coating polydopamine (pDA) and binding Hep and BSA. The experiments of hemocompatibility indicate that Hep and BSA grafted onto membranes suppress the adhesion of platelet and enhance the anticoagulation ability of PSF membranes. Furthermore, the protein adsorption tests reveal that Hep and BSA immobilized onto membranes depress the protein absorption and develop antifouling-protein ability of pristine membrane. This study proves a convenient and simple approach to graft two functional organic polymers which, respectively, play a vital role and then improve the hemocompatibility and biocompatibility of PSF membranes for their biomedical and blood-contacting applications. PMID:27018964

  17. Rotational diffusion of bovine serum albumin denaturated by sodium dodecylsulfate, According to data from tryptophan fluorescence

    NASA Astrophysics Data System (ADS)

    Vlasova, I. M.; Zhuravleva, V. V.; Saletskii, A. M.

    2014-03-01

    The rotational diffusion of bovine serum albumin (BSA) molecules in solutions with different concentrations of the anionic detergent sodium dodecylsulfate (SDS) at different pH values is investigated, yielding information on the denaturation of BSA under the action of SDS. It is found from the increased degree of polarization in the tryptophan fluorescence of BSA and the registered parameters for the rotational diffusion of BSA molecules that the denaturation of BSA under the action of SDS at pH values less than the isoelectric point (pI) of BSA (4-9) is a two-stage process. It is shown that the first stage of BSA denaturation common for all pH values is the decondensation of BSA globules, while the second stage of BSA denaturation at pH greater than the pI of BSA is the unfolding of the protein's amino acid chain. It is concluded that the denaturation of BSA under the action of SDS proceeds more deeply at pH values greater than the pI of BSA.

  18. Preparation of albumin based nanoparticles for delivery of fisetin and evaluation of its cytotoxic activity.

    PubMed

    Ghosh, Pooja; Singha Roy, Atanu; Chaudhury, Susmitnarayan; Jana, Saikat Kumar; Chaudhury, Koel; Dasgupta, Swagata

    2016-05-01

    Fisetin is a well known flavonoid that shows several properties such as antioxidant, antiviral and anticancer activities. Its use in the pharmaceutical field is limited due to its poor aqueous solubility which results in poor bioavailability and poor permeability. The aim of our present study is to prepare fisetin loaded human serum albumin nanoparticles to improve its bioavailability. The nanoparticles were prepared by a desolvation method and characterized by spectroscopic and microscopic techniques. The particles were smooth and spherical in nature with an average size of 220±8nm. The encapsulation efficiency was found to be 84%. The in vitro release profile showed a biphasic pattern and the release rate increases with increase in ionic strength of solution. We have also confirmed the antioxidant activity of the prepared nanoparticles by a DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Further its anticancer activity was evaluated using MCF-7 breast cancer cell lines. Our findings suggest that fisetin loaded HSA nanoparticles could be used to transfer fisetin to target areas under specific conditions and thus may find use as a delivery vehicle for the flavonoid. PMID:26820351

  19. Fluorescence modulation and associative behavior of lumazine in hydrophobic domain of micelles and bovine serum albumin.

    PubMed

    Moyon, N Shaemningwar; Islam, Mullah Muhaiminul; Phukan, Smritakshi; Mitra, Sivaprasad

    2013-04-01

    The photophysical behavior of the deprotonated form of lumazine (Lum-anion) was studied in biologically relevant surfactant systems like sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB) and TritonX-100 (TX-100) and also model water soluble protein, bovine serum albumin (BSA), using steady-state and time-resolved fluorescence spectroscopy in buffer solution of pH 12.0. The association constant values were calculated from modulated fluorescence intensity of Lum-anion in different medium. The interaction of non-ionic surfactant TX-100 was found to be about 10 times greater than SDS and CTAB. However, while the driving force of binding in SDS and/or TX-100 is mainly hydrophobic in nature, electrostatic interaction with the oppositely charged micellar head group is the predominant factor in CTAB. The thermodynamic parameters like enthalpy (ΔH) and entropy (ΔS) change, etc., corresponding to the binding of Lum-anion with BSA were estimated by performing the fluorescence titration experiment at different temperatures. Thermodynamically favorable and strong binding of Lum-anion (K~10(4) M(-1)) into BSA is due to hydrophobic interaction in the ligand binding domain II. However, the binding mechanism is entirely different in presence of protein denaturing agent like urea and electrostatic interaction plays a major role under this condition. PMID:23501728

  20. Interaction Studies of Greenly Synthesized Gold Nanoparticles with Bovine Serum Albumin (BSA) Using Fluorescence Spectroscopy.

    PubMed

    Ravikumar, Sambandam; Sreekanth, T V M; Eom, In-Yong

    2015-12-01

    In the present study, gold nanoparticles (AuNPs) with an average particle size of -41.23 nm were synthesized using eco-friendly reducing material (i.e., aqueous Nelumbo nucifera root extract). Rapid reduction results in the formation of polydispersed nanoparticles. The formation of AuNPs was characterized by surface plasmon resonance (SPR) which was determined by UV-Vis spectra (band at 544 nm), FTIR, SEM-EDX, TEM, HR-TEM, and XRD. This study aims to investigate the interaction between AuNPs and Bovine Serum Albumin (BSA) using fluorescence spectroscopy. The analysis of fluorescence spectra and intensity at physiological pH in an aqueous solution indicates that AuNPs have a potent ability to quench the BSA fluorescence by both quenching mechanisms. Resonance light scattering spectra indicated the formation of BSA-AuNPs complex. The number of binding sites and binding constants were determined based on fluorescence quenching at different temperatures. The thermodynamic parameters were also calculated at various temperatures that indicate that hydrophobic forces are abundant in the AuNPs-BSA complex. Negative ΔG degrees values suggest that the binding process is spontaneous. Synchronous fluorescence spectra showed a blue shift and CD spectra showed an increase in a-helicity content which is an indication of increasing hydrophobicity. PMID:26682387

  1. Formulation and evaluation of albumin microspheres and its enteric coating using a spray-dryer.

    PubMed

    Bejugam, Naveen K; Uddin, Akm N; Gayakwad, Sanjay G; D'Souza, Martin J

    2008-12-01

    This study optimized and evaluated the conditions for surface coating of microspheres using a spray-dryer. Four formulations of Bromophenol blue (BPB)-loaded albumin microspheres were prepared using a spray-dryer, cross-linked at different concentrations and time periods. One of the optimized formulations with the desired characteristics was selected for enteric coating with Eudragit L100-55. The procedure involved suspending BPB microspheres in polymer solution and spray-drying it. Four enteric coated formulations were prepared with different concentrations of microspheres in suspension (0.25 and 0.5%w/v) and polymer concentrations (0.25 and 0.5%w/v). Change in the mean particle size after coating was determined using a Laser Particle Counter. The surface coating technique employed did not significantly increase the particle size. Enteric coating efficiency was determined in simulated gastric fluid. Compared to the uncoated microspheres the cumulative amount of drug released from coated microspheres was significantly lower for 3 h, implying efficient surface coating. PMID:19003560

  2. Human serum albumin reduces the potency of acetylcholinesterase inhibitor based drugs for Alzheimer's disease.

    PubMed

    Islam, Mullah Muhaiminul; Gurung, Arun Bahadur; Bhattacharjee, Atanu; Aguan, Kripamoy; Mitra, Sivaprasad

    2016-04-01

    Human serum albumin (HSA) induced modulation of acetylcholinesterase (AChE) inhibition activity of four well-known cholinergic inhibitors like tacrine hydrochloride (TAC), donepezil hydrochloride monohydrate (DON), (-) Huperzine A (HuPA), eserine (ESE) was monitored quantitatively by Ellman's method. Kinetic analysis of enzyme hydrolysis reaction revealed that while the mechanism of inhibition does not change significantly, the inhibition efficiency changes drastically in presence of HSA, particularly for DON and TAC. However, interestingly, no notable difference was observed in the cases of HuPA and/or ESE. For example, the IC50 value of AChE inhibition increases by almost 135% in presence of ∼250 μM HSA (IC50 = 159 ± 8 nM) while comparing with aqueous buffer solution of pH 8.0 (IC50 = 68 ± 4 nM) in DON. On the other hand, the change is almost insignificant (<10%) in case of HuPA under the similar condition. The experimentally observed difference in the extent of modulatory effect was correlated with the sequestration ability of HSA towards different drugs predicted from molecular docking calculations. The result in this study demonstrates the importance to consider the plasma protein binding tendency of a newly synthesized AD drug before claiming its potency over the existing one. Further, development of new and intelligent delivery medium that shields the administered drugs from serum adsorption may reduce the optimal drug dose requirement. PMID:26902639

  3. Interaction between endothelial cells and albumin encapsulated droplets in Poiseuille flow

    NASA Astrophysics Data System (ADS)

    Seda, Robinson; Fowlkes, J. Brian; Bull, Joseph

    2012-11-01

    Acoustic droplet vaporization (ADV) of DDFP encapsulated microdroplets has the ability to transform these emulsions into larger gas emboli capable of occluding blood vessels for therapy. An albumin shell is able to stabilize the droplet's superheated core, but can also interact with endothelial cells (EC) at the vessel wall if in close proximity. Radial migration of these microdroplets could bring them close enough to make this interaction possible leading to bioeffects that include cell detachment and death if an ADV event occurs. The purpose of this study is to investigate the hydrodynamic conditions (i.e. shear stresses) that make possible this EC-droplet interaction. A flow chamber coated with a monolayer of EC and connected to a syringe pump is used to flow a DDFP droplet solution at physiological shear stresses (1-50 dyne/cm2) and inspected for droplet attachment. Droplets have been observed to interact and reversibly attach to EC in a static environment, thus it is expected that at low shear stress values interaction and further attachment will be possible. Knowing the flow conditions at which this interaction is likely to occur will aid in preventative measures to avoid significant bioeffects associated with ADV near the vessel wall. This work is supported by NIH grant R01EB006476.

  4. The interaction between 4-aminoantipyrine and bovine serum albumin: multiple spectroscopic and molecular docking investigations.

    PubMed

    Teng, Yue; Liu, Rutao; Li, Chao; Xia, Qing; Zhang, Pengjun

    2011-06-15

    4-Aminoantipyrine (AAP) is widely used in the pharmaceutical industry, in biochemical experiments and in environmental monitoring. AAP as an aromatic pollutant in the environment poses a great threat to human health. To evaluate the toxicity of AAP at the protein level, the effects of AAP on bovine serum albumin (BSA) were investigated by multiple spectroscopic techniques and molecular modeling. After the inner filter effect was eliminated, the experimental results showed that AAP effectively quenched the intrinsic fluorescence of BSA via static quenching. The number of binding sites, the binding constant, the thermodynamic parameters and binding subdomain were measured, and indicated that AAP could spontaneously bind with BSA on subdomain IIIA through electrostatic forces. Molecular docking results revealed that AAP interacted with the Glu 488 and Glu 502 residues of BSA. Furthermore, the conformation of BSA was demonstrably changed in the presence of AAP. The skeletal structure of BSA loosened, exposing internal hydrophobic aromatic ring amino acids and peptide strands to the solution. PMID:21497437

  5. Binding of manganese and iron tetraphenylporphine sulfonates to albumin is relevant to their contrast properties.

    PubMed

    Yushmanov, V E; Tominaga, T T; Borissevitch, I E; Imasato, H; Tabak, M

    1996-01-01

    The interaction of Fe(III) and Mn(III) complexes of TPPS4 with bovine serum albumin (BSA) was studied by T1 relaxation measurements of water protons and high resolution 1H NMR of the porphyrin moieties. At excess of BSA, both metalloporphyrins bind to BSA as the high spin monomers. The relaxivity of bound MnTPPS4 is significantly higher as compared to the free form in solution. When metalloporphyrins are in excess, they aggregate at the BSA surface, up to two MnTPPS4, and up to 10-15 FeTPPS4 units per BSA globule. Bound aggregates are unable to enhance magnetic relaxation of water protons due to the antiferromagnetic coupling between metal ions in the aggregates. Therefore, the dose-effect dependences for metalloporphyrins in the range of metalloporphyrin/BSA ratio of 0 to 25 at the constant BSA concentration at pH 7.4 are characterized by a local maximum at about 2 for MnTPPS4, and a global maximum at about 3 for FeTPPS4, MnTPPS4 complex is more effective than FeTPPS4 in the whole concentration range. It is suggested that the difference in binding and aggregation properties of metalloporphyrins may be relevant to their relaxation efficiency in vivo, blood transport, and biodistribution. PMID:8725191

  6. The effect of Berberine on the secondary structure of human serum albumin

    NASA Astrophysics Data System (ADS)

    Li, Ying; He, WenYing; Tian, Jianniao; Tang, Jianghong; Hu, Zhide; Chen, Xingguo

    2005-05-01

    The presence of several high affinity binding sites on human serum albumin (HSA) makes it a possible target for many drugs. This study is designed to examine the effect of Berberine (an ancient Chinese drug used for antimicrobial, antiplasmodial, antidiarrheal and cardiovascular) on the solution structure of HSA using fluorescence, Fourier transform infrared (FT-IR), circular dichroism (CD) spectroscopic methods. The fluorescence spectroscopic results show that the fluorescence intensity of HSA was significantly decreased in the presence of Berberine. The Scatchard's plots indicated that the binding of Berberine to HSA at 296, 303, 318 K is characterized by one binding site with the binding constant is 4.071(±0.128)×10 4, 3.741(±0.089)×10 4, 3.454(±0.110)×10 4 M -1, respectively. The protein conformation is altered (FT-IR and CD data) with reductions of α-helices from 54 to 47% for free HSA to 45-32% and with increases of turn structure5% for free HSA to 18% in the presence of Berberine. The binding process was exothermic, enthalpy driven and spontaneous, as indicated by the thermodynamic analyses, Berberine bound to HSA was mainly based on hydrophobic interaction and electrostatic interaction cannot be excluded from the binding. Furthermore, the displace experiments indicate that Berberine can bind to the subdomain IIA, that is, high affinity site (site II).

  7. Studies of drug interactions with glycated human serum albumin by high-performance affinity chromatography

    PubMed Central

    Matsuda, Ryan; Kye, So-Hwang; Anguizola, Jeanethe; Hage, David S.

    2015-01-01

    Diabetes is a health condition associated with elevated levels of glucose in the bloodstream and affects 366 million people worldwide. Type II diabetes is often treated with sulfonylurea drugs, which are known to bind tightly in blood to the transport protein human serum albumin (HSA). One consequence of the elevated levels of glucose in diabetes is the non-enzymatic glycation of proteins such as HSA. Several areas of HSA are now known to be affected by glycation-related modifications, which may in turn affect the binding of sulfonylurea drugs and other solutes to this protein. This review discusses some recent studies that have examined these changes in drug-protein binding by employing high-performance affinity chromatography (HPAC). A description of the theoretical and experimental techniques that were used in these studies is given. The information on drug interactions with glycated HSA, as obtained through this method, is also summarized. In addition, the potential advantages of this approach in the areas of biointeraction analysis and personalized medicine are considered. PMID:26526139

  8. Studies of drug interactions with glycated human serum albumin by high-performance affinity chromatography.

    PubMed

    Matsuda, Ryan; Kye, So-Hwang; Anguizola, Jeanethe; Hage, David S

    2014-08-01

    Diabetes is a health condition associated with elevated levels of glucose in the bloodstream and affects 366 million people worldwide. Type II diabetes is often treated with sulfonylurea drugs, which are known to bind tightly in blood to the transport protein human serum albumin (HSA). One consequence of the elevated levels of glucose in diabetes is the non-enzymatic glycation of proteins such as HSA. Several areas of HSA are now known to be affected by glycation-related modifications, which may in turn affect the binding of sulfonylurea drugs and other solutes to this protein. This review discusses some recent studies that have examined these changes in drug-protein binding by employing high-performance affinity chromatography (HPAC). A description of the theoretical and experimental techniques that were used in these studies is given. The information on drug interactions with glycated HSA, as obtained through this method, is also summarized. In addition, the potential advantages of this approach in the areas of biointeraction analysis and personalized medicine are considered. PMID:26526139

  9. A comparative study of the interaction of Tamiflu and Oseltamivir carboxylate with bovine serum albumin.

    PubMed

    Vishkaee, Tahereh Sadigh; Mohajerani, Niloufar; Nafisi, Shohreh

    2013-02-01

    Oseltamivir phosphate (Tamiflu) is a pro-drug that is metabolized to its active form (Oseltamivir carboxylate), after oral administration. OC inhibits influenza A and B neuraminidases in vitro and OP inhibits influenza virus infection and replication in vitro. Serum albumin is the most abundant of the proteins in the circulatory system of a wide variety of organisms and plays an important role in the transport and deposition of many drugs. The aim of this study was to examine the interaction of BSA with Tamiflu and Oseltamivir carboxylate in aqueous solution at physiological conditions, using a constant protein concentration and various drug contents. FTIR, UV-Vis spectroscopic methods were used to determine the drugs binding mode, the binding constant and the effects of drug complexation on protein secondary structure. Structural analysis showed that OP and OC bind BSA with overall binding constants of K(OP-BSA)=1.88 (±0.16)×10(4)M(-1) and K(OC-BSA)=5.7 (±0.09)×10(2)M(-1). Drug complexation alters protein conformation by major reduction of α-helix and random coil and increase of β-sheet and turn structures that indicate a partial protein destabilization. The results suggest that BSA might act as carrier proteins for OP in delivering it to target molecules. PMID:23353784

  10. nanoparticles via a facile one-step solvothermal process for adsorption of bovine serum albumin

    NASA Astrophysics Data System (ADS)

    Shen, Mao; Yu, Yujing; Fan, Guodong; Chen, Guang; Jin, Ying min; Tang, Wenyuan; Jia, Wenping

    2014-06-01

    Preparation of magnetic nanoparticles coated with chitosan (CS-coated Fe3O4 NPs) in one step by the solvothermal method in the presence of different amounts of added chitosan is reported here. The magnetic property of the obtained magnetic composite nanoparticles was confirmed by X-ray diffraction (XRD) and magnetic measurements (VSM). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) allowed the identification of spherical nanoparticles with about 150 nm in average diameter. Characterization of the products by Fourier transform infrared spectroscopy (FTIR) demonstrated that CS-coated Fe3O4 NPs were obtained. Chitosan content in the obtained nanocomposites was estimated by thermogravimetric analysis (TGA). The adsorption properties of the CS-coated Fe3O4 NPs for bovine serum albumin (BSA) were investigated under different concentrations of BSA. Compared with naked Fe3O4 nanoparticles, the CS-coated Fe3O4 NPs showed a higher BSA adsorption capacity (96.5 mg/g) and a fast adsorption rate (45 min) in aqueous solutions. This work demonstrates that the prepared magnetic nanoparticles have promising applications in enzyme and protein immobilization.

  11. Quantification of total content of non-esterified fatty acids bound to human serum albumin.

    PubMed

    Pavićević, Ivan D; Jovanović, Vesna B; Takić, Marija M; Aćimović, Jelena M; Penezić, Ana Z; Mandić, Ljuba M

    2016-09-10

    Non-esterified fatty acids bound to the human serum albumin (HSA) contribute to several HSAs properties of special concern in pathologies, for instance to the reactivity of the free HSA-Cys34 thiol group (important antioxidative thiol pool in plasma), and to the affinity for binding of molecules and ions (for example cobalt as a prominent biomarker in heart ischemia). Therefore, the method for determination of FAs bound to HSA was developed. FAs were released from HSA (previously isolated from serum by ammonium sulfate precipitation) using acidic copper(II) sulfate in phosphoric acid, extracted by n-heptane-chloroform (4:1, v/v) mixture, spotted on TL silica-gel and then developed with n-heptane-chloroform-acetic acid (5:3:0.3, v/v/v). Common office flatbed scanner and software solution for densitometric image analysis, developed in R, were used. The linearity of calibration curve in concentration range from 0.1 to 5.0mmol/L stearic acid was achieved. The method was proved to be precise (with RSD of 1.4-4.7%) and accurate. Accuracy was examined by standard addition method (recoveries 97.2-102.5%) and by comparison to results of GC. The method is sample saving, technically less demanding, and cheap, and therefore suitable for determination of FAs/HSA ratio when elevated concentrations of free FAs are reliable diagnostic/risk parameter of pathological states. PMID:27394177

  12. Suppression of albumin enhancer activity by H-ras and AP-1 in hepatocyte cell lines.

    PubMed Central

    Hu, J; Isom, H C

    1994-01-01

    We demonstrated, using a transient transfection assay, that the albumin enhancer increased the expression of the albumin promoter in a highly differentiated, simian virus 40 (SV40)-immortalized hepatocyte cell line, CWSV1, but was not functional in two ras-transformed cell lines (NR3 and NR4) derived from CWSV1 by stable transfection with the T24ras oncogene. A transient cotransfection assay showed that T24ras and normal c-Ha-ras were each able to inhibit the activity of the albumin enhancer in an immortal hepatocyte cell line. DNase I footprinting and gel mobility shift assays demonstrated that the DNA binding activities specific to the albumin enhancer were not decreased in the ras-transformed cells. ras also did not diminish the expression of HNF1 alpha, C/EBP alpha, HNF3 alpha, HNF3 beta, or HNF3 gamma but did significantly increase AP-1 binding activity. Three AP-1 binding sites were identified within the albumin enhancer, and DNA binding activities specific to these AP-1 sites were induced in the ras-transformed hepatocytes. Subsequent functional assays showed that overexpression of c-jun and c-fos inhibited the activity of the albumin enhancer. Site-directed mutagenesis of the AP-1 binding sites in the albumin enhancer partially abrogated the suppressing effect of ras and c-jun/c-fos on the enhancer. These functional studies therefore supported the results of the structural studies with AP-1. We conclude that the activity of the albumin enhancer is subject to regulation by ras signaling pathways and that the effect of ras on the albumin enhancer activity may be mediated by AP-1. Images PMID:8114691

  13. Serum albumin coating of demineralized bone matrix results in stronger new bone formation.

    PubMed

    Horváthy, Dénes B; Vácz, Gabriella; Szabó, Tamás; Szigyártó, Imola C; Toró, Ildikó; Vámos, Boglárka; Hornyák, István; Renner, Károly; Klára, Tamás; Szabó, Bence T; Dobó-Nagy, Csaba; Doros, Attila; Lacza, Zsombor

    2016-01-01

    Blood serum fractions are hotly debated adjuvants in bone replacement therapies. In the present experiment, we coated demineralized bone matrices (DBM) with serum albumin and investigated stem cell attachment in vitro and bone formation in a rat calvaria defect model. In the in vitro experiments, we observed that significantly more cells adhere to the serum albumin coated DBMs at every time point. In vivo bone formation with albumin coated and uncoated DBM was monitored biweekly by computed tomography until 11 weeks postoperatively while empty defects served as controls. By the seventh week, the bone defect in the albumin group was almost completely closed (remaining defect 3.0 ± 2.3%), while uncoated DBM and unfilled control groups still had significant defects (uncoated: 40.2 ± 9.1%, control: 52.4 ± 8.9%). Higher density values were also observed in the albumin coated DBM group. In addition, the serum albumin enhanced group showed significantly higher volume of newly formed bone in the microCT analysis and produced significantly higher breaking force and stiffness compared to the uncoated grafts (peak breaking force: uncoated: 15.7 ± 4 N, albumin 46.1 ± 11 N). In conclusion, this investigation shows that implanting serum albumin coated DBM significantly reduces healing period in nonhealing defects and results in mechanically stronger bone. These results also support the idea that serum albumin coating provides a convenient milieu for stem cell function, and a much improved bone grafting success can be achieved without the use of exogenous stem cells. PMID:25677203

  14. Role played by Disabled-2 in albumin induced MAP Kinase signalling

    SciTech Connect

    Diwakar, Ramaswamy Pearson, Alexander L.; Colville-Nash, Paul; Baines, Deborah L.; Dockrell, Mark E.C.

    2008-02-15

    Albumin has been shown to activate the mitogen activated protein kinase (MAPK) pathway in proximal tubular cells (PTECs) of the kidney. Megalin, the putative receptor for albumin has potential signalling properties. However, the mechanisms by which megalin signals are unclear. The adaptor phosphoprotein Disabled-2 (Dab2) is known to interact with the cytoplasmic tail of megalin and may be involved in albumin-mediated MAPK signalling. In this study, we investigated the role of Dab2 in albumin-mediated MAPK signalling and further studied the role of Dab2 in albumin-induced TGF{beta}-1 secretion, a MAPK dependent event. We used RNA interference to knockdown Dab2 protein abundance in HKC-8 cells a model of human PTECs. Albumin activated ERK1,2 and Elk-1 in a MEK-1 dependent manner and resulted in secretion of TGF{beta}-1. In the absence of albumin, knockdown of Dab2 resulted in a trend towards increase in pERK1,2 consistent with its putative role as an inhibitor of cell proliferation. However albumin-induced ERK1,2 activation was completely abolished by Dab2 knockdown. Dab2 knockdown did not however result in inhibition of albumin-induced TGF{beta}-1 secretion. These results suggest that Dab2 is a ligand dependent bi-directional regulator of ERK1,2 activity by demonstrating that in addition to its more traditional role as an inhibitor of ERK1,2 it may also activate ERK1,2.

  15. Focal Mechanism Solutions of the 2008 Wenchuan earthquake sequence from P-wave polarities and SH/P amplitude ratios: new results and implications

    NASA Astrophysics Data System (ADS)

    Tian, Yuan; Ning, Jieyuan; Yu, Chunquan; Cai, Chen; Tao, Kai

    2013-12-01

    The 2008 Wenchuan earthquake, a major intraplate earthquake with M w 7.9, occurred on the slowly deforming Longmenshan fault. To better understand the causes of this devastating earthquake, we need knowledge of the regional stress field and the underlying geodynamic processes. Here, we determine focal mechanism solutions (FMSs) of the 2008 Wenchuan earthquake sequence (WES) using both P-wave first-motion polarity data and SH/P amplitude ratio (AR) data. As P-wave polarities are more reliable information, they are given priority over SH/P AR, the latter of which are used only when the former has loose constraint on the FMSs. We collect data from three categories: (1) permanent stations deployed by the China Earthquake Administration (CEA); (2) the Western Sichuan Passive Seismic Array (WSPSA) deployed by Institute of Geology, CEA; (3) global stations from Incorporated Research Institutions for Seismology. Finally, 129 events with magnitude over M s 4.0 in the 2008 WES are identified to have well-constrained FMSs. Among them, 83 are well constrained by P-wave polarities only as shown by Cai et al. (Earthq Sci 24(1):115-125, 2011), and the rest of which are newly constrained by incorporating SH/P AR. Based on the spatial distribution and FMSs of the WES, we draw following conclusions: (1) the principle compressional directions of most FMSs of the WES a