Relationship between changed alveolar-capillary permeability and angiotensin converting enzyme activity in serum in sarcoidosis.

OpenAIRE

Eklund, A; Blaschke, E

1986-01-01

The effect of altered alveolar-capillary permeability on angiotensin converting enzyme (ACE) activity in serum (SACE) was studied in 45 patients with sarcoidosis and 21 healthy controls. In sarcoidosis increased albumin concentrations in the bronchoalveolar lavage fluid (L albumin) and increased ratios of L albumin to albumin in serum (S albumin) indicated an increased permeability of the alveolar-capillary membrane. ACE activity in the lavage fluid (LACE) was correlated with the number of al...

Improved anticancer effects of albumin-bound paclitaxel nanoparticle via augmentation of EPR effect and albumin-protein interactions using S-nitrosated human serum albumin dimer.

Science.gov (United States)

Kinoshita, Ryo; Ishima, Yu; Chuang, Victor T G; Nakamura, Hideaki; Fang, Jun; Watanabe, Hiroshi; Shimizu, Taro; Okuhira, Keiichiro; Ishida, Tatsuhiro; Maeda, Hiroshi; Otagiri, Masaki; Maruyama, Toru

2017-09-01

In the latest trend of anticancer chemotherapy research, there were many macromolecular anticancer drugs developed based on enhanced permeability and retention (EPR) effect, such as albumin bound paclitaxel nanoparticle (nab- PTX, also called Abraxane ® ). However, cancers with low vascular permeability posed a challenge for these EPR based therapeutic systems. Augmenting the intrinsic EPR effect with an intrinsic vascular modulator such as nitric oxide (NO) could be a promising strategy. S-nitrosated human serum albumin dimer (SNO-HSA Dimer) shown promising activity previously was evaluated for the synergistic effect when used as a pretreatment agent in nab-PTX therapy against various tumor models. In the high vascular permeability C26 murine colon cancer subcutaneous inoculation model, SNO-HSA Dimer enhanced tumor selectivity of nab-PTX, and attenuated myelosuppression. SNO-HSA Dimer also augmented the tumor growth inhibition of nab-PTX in low vascular permeability B16 murine melanoma subcutaneous inoculation model. Furthermore, nab-PTX therapy combined with SNO-HSA Dimer showed higher antitumor activity and improved survival rate of SUIT2 human pancreatic cancer orthotopic model. In conclusion, SNO-HSA Dimer could enhance the therapeutic effect of nab-PTX even in low vascular permeability or intractable pancreatic cancers. The possible underlying mechanisms of action of SNO-HSA Dimer were discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

PLACENTAL SECRETORY FACTORS INFLUENCE TO THP-1 CELLS PHENOTYPE AND THP-1 CELLS TRANSENDOTHELIAL MIGRATION

Directory of Open Access Journals (Sweden)

O. I. Stepanova

2013-01-01

Full Text Available Decidual and placental macrophage pools are renewed due to its transendothelial monocyte migration from peripheral blood. Tissue macrophages control placental development and provide fetomaternal immunological tolerance. Preeclamptic pregnancy is accompanied by increased monocyte migration to decidual tissue and local inflammatory events. Regulatory mechanisms of monocyte recruitment to placental and decidual tissues is still unclear. Therefore we investigated the influence soluble placental factors (SPFs during the first- and third-trimester normal pregnancy, as compared to effects of these factors in preeclamptic pregnancy. We studied biological actions of SPF upon transendothelial migration of monocyte-like THP-1 cells and their phenotypic pattern. Transendothelial migration of THP-1 cells was more intensive with firsttrimester SPFs from normal pregnancy, when compared with third-trimester samples, and it was accompanied by decreased CD11a expression. SPFs from pre-eclamptic pregnancy caused an increase in transendothelial migration of THP-1 cells, as compared to SPFs from normal pregnancies, being accompanied by increased CD11b expression. The present study was supported by grants ГК №  02.740.11.0711, НШ-3594.2010.7, МД-150.2011.7 and a grant from St.-Petersburg Goverment for young scientists.

Human neutrophils facilitate tumor cell transendothelial migration.

LENUS (Irish Health Repository)

Wu, Q D

2012-02-03

Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

The diaphragms of fenestrated endothelia: gatekeepers of vascular permeability and blood composition.

Science.gov (United States)

Stan, Radu V; Tse, Dan; Deharvengt, Sophie J; Smits, Nicole C; Xu, Yan; Luciano, Marcus R; McGarry, Caitlin L; Buitendijk, Maarten; Nemani, Krishnamurthy V; Elgueta, Raul; Kobayashi, Takashi; Shipman, Samantha L; Moodie, Karen L; Daghlian, Charles P; Ernst, Patricia A; Lee, Hong-Kee; Suriawinata, Arief A; Schned, Alan R; Longnecker, Daniel S; Fiering, Steven N; Noelle, Randolph J; Gimi, Barjor; Shworak, Nicholas W; Carrière, Catherine

2012-12-11

Fenestral and stomatal diaphragms are endothelial subcellular structures of unknown function that form on organelles implicated in vascular permeability: fenestrae, transendothelial channels, and caveolae. PV1 protein is required for diaphragm formation in vitro. Here, we report that deletion of the PV1-encoding Plvap gene in mice results in the absence of diaphragms and decreased survival. Loss of diaphragms did not affect the fenestrae and transendothelial channels formation but disrupted the barrier function of fenestrated capillaries, causing a major leak of plasma proteins. This disruption results in early death of animals due to severe noninflammatory protein-losing enteropathy. Deletion of PV1 in endothelium, but not in the hematopoietic compartment, recapitulates the phenotype of global PV1 deletion, whereas endothelial reconstitution of PV1 rescues the phenotype. Taken together, these data provide genetic evidence for the critical role of the diaphragms in fenestrated capillaries in the maintenance of blood composition. Copyright © 2012 Elsevier Inc. All rights reserved.

Direct quantification of transendothelial electrical resistance in organs-on-chips

NARCIS (Netherlands)

van der Helm, Marieke Willemijn; Odijk, Mathieu; Frimat, Jean-Philippe; van der Meer, Andries Dirk; Eijkel, Jan C.T.; van den Berg, Albert; Segerink, Loes Irene

2016-01-01

Measuring transendothelial or transepithelial electrical resistance (TEER) is a widely used method to monitor cellular barrier tightness in organs-on-chips. Unfortunately, integrated electrodes close to the cellular barrier hamper visual inspection of the cells or require specialized cleanroom

Usefulness of vitamin A binding protein as a marker for capillary endothelial permeability

Energy Technology Data Exchange (ETDEWEB)

Ishizaka, Akitoshi; Suzuki, Yukio; Kanazawa, Minoru; Kubo, Atsushi; Kawashiro, Takeo [Keio Univ., Tokyo (Japan). School of Medicine

1992-06-01

We performed a preliminary study to assess the usefulness of Vitamin A binding protein (VABP) as a gamma-camera marker for capillary endothelial permeability. We used a guinea pig model of endotoxin (LPS) induced acute lung injury. We calculated the concentration ratio of either {sup 125}I-albumin or {sup 125}I-VABP in lung tissue to that in plasma (tissue plasma ratio; T/P) as a parameter of capillary endothelial permeability. {sup 99m}Tc-diethylene triamine pentaacetic acid (DTPA) was used as marker for pulmonary interstitial volume. We estimated wet to dry lung weight ratio as a parameter of lung water accumulation (W/D). LPS increased the T/P of {sup 125}I-albumin and W/D, suggesting the development of permeability edema. The T/P for {sup 125}I-VABP was also increased, indicating that {sup 125}I-VABP can be used to detect elevated capillary endothelial permeability. In both groups, LPS and saline, the T/P was higher for {sup 125}I-VABP than for {sup 125}I-albumin. These data suggest that the pulmonary capillary endothelium is more permeable to VABP than albumin. (author).

Albumin modulates S1P delivery from red blood cells in perfused microvessels: mechanism of the protein effect.

Science.gov (United States)

Adamson, R H; Clark, J F; Radeva, M; Kheirolomoom, A; Ferrara, K W; Curry, F E

2014-04-01

Removal of plasma proteins from perfusates increases vascular permeability. The common interpretation of the action of albumin is that it forms part of the permeability barrier by electrostatic binding to the endothelial glycocalyx. We tested the alternate hypothesis that removal of perfusate albumin in rat venular microvessels decreased the availability of sphingosine-1-phosphate (S1P), which is normally carried in plasma bound to albumin and lipoproteins and is required to maintain stable baseline endothelial barriers (Am J Physiol Heart Circ Physiol 303: H825-H834, 2012). Red blood cells (RBCs) are a primary source of S1P in the normal circulation. We compared apparent albumin permeability coefficients [solute permeability (Ps)] measured using perfusates containing albumin (10 mg/ml, control) and conditioned by 20-min exposure to rat RBCs with Ps when test perfusates were in RBC-conditioned protein-free Ringer solution. The control perfusate S1P concentration (439 ± 46 nM) was near the normal plasma value at 37 °C and established a stable baseline Ps (0.9 ± 0.4 × 10(-6) cm/s). Ringer solution perfusate contained 52 ± 8 nM S1P and increased Ps more than 10-fold (16.1 ± 3.9 × 10(-6) cm/s). Consistent with albumin-dependent transport of S1P from RBCs, S1P concentrations in RBC-conditioned solutions decreased as albumin concentration, hematocrit, and temperature decreased. Protein-free Ringer solution perfusates that used liposomes instead of RBCs as flow markers failed to maintain normal permeability, reproducing the "albumin effect" in these mammalian microvessels. We conclude that the albumin effect depends on the action of albumin to facilitate the release and transport of S1P from RBCs that normally provide a significant amount of S1P to the endothelium.

Minocycline affects human neutrophil respiratory burst and transendothelial migration.

Science.gov (United States)

Parenti, Astrid; Indorato, Boris; Paccosi, Sara

2017-02-01

This study aimed at investigating the in vitro activity of minocycline and doxycycline on human polymorphonuclear (h-PMN) cell function. h-PMNs were isolated from whole venous blood of healthy subjects; PMN oxidative burst was measured by monitoring ROS-induced oxidation of luminol and transendothelial migration was studied by measuring PMN migration through a monolayer of human umbilical vein endothelial cells. Differences between multiple groups were determined by ANOVA followed by Tukey's multiple comparison test; Student's t test for unpaired data for two groups. Minocycline (1-300 µM) concentration dependently and significantly inhibited oxidative burst of h-PMNs stimulated with 100 nM fMLP. Ten micromolar concentrations, which are superimposable to C max following a standard oral dose of minocycline, promoted a 29.8 ± 4 % inhibition of respiratory burst (P minocycline impaired PMN transendothelial migration, with maximal effect at 100 µM (42.5 ± 7 %, inhibition, n = 5, P minocycline exerted on innate immune h-PMN cell function.

Asymmetric [14C]albumin transport across bullfrog alveolar epithelium

International Nuclear Information System (INIS)

Kim, K.J.; LeBon, T.R.; Shinbane, J.S.; Crandall, E.D.

1985-01-01

Bullfrog lungs were prepared as planar sheets and bathed with Ringer solution in Ussing chambers. In the presence of a constant electrical gradient (20, 0, or -20 mV) across the tissue, 14 C-labeled bovine serum albumin or inulin was instilled into the upstream reservoir and the rate of appearance of the tracer in the downstream reservoir was monitored. Two lungs from the same animal were used to determine any directional difference in tracer fluxes. An apparent permeability coefficient was estimated from a relationship between normalized downstream radioactivities and time. Results showed that the apparent permeability of albumin in the alveolar to pleural direction across the alveolar epithelial barrier is 2.3 X 10(-7) cm/s, significantly greater (P less than 0.0005) than that in the pleural to alveolar direction (5.3 X 10(-8) cm/s) when the tissue was short circuited. Permeability of inulin, on the other hand, did not show any directional dependence and averaged 3.1 X 10(-8) cm/s in both directions. There was no effect on radiotracer fluxes permeabilities of different electrical gradients across the tissue. Gel electrophoretograms and corresponding radiochromatograms suggest that the large and asymmetric isotope fluxes are not primarily due to digestion or degradation of labeled molecules. Inulin appears to traverse the alveolar epithelial barrier by simple diffusion through hydrated paracellular pathways. On the other hand, [ 14 C]albumin crosses the alveolar epithelium more rapidly than would be expected by simple diffusion. These asymmetric and large tracer fluxes suggest that a specialized mechanism is present in alveolar epithelium that may be capable of helping to remove albumin from the alveolar space

Simple clinical means of documenting increased pulmonary endothelial permeability to protein

Energy Technology Data Exchange (ETDEWEB)

Mishkin, F.S.; Niden, A.; Kumar, A.; Thomas, A.; Reese, I.C.; Vasinrapee, P.

1987-02-20

The authors investigated a simple method that can be used at the bedside for documenting the net accumulation of albumin in the lung. The technique employs measurement with a computer-linked gamma camera of the activity ratio in an area of the right lung compared with the same-sized area in the heart at 20 minutes and three hours following intravenous injection of technetium Tc 99m albumin. They applied this measurement to three groups of patients: a control group and patients with roentgenographic evidence of edema classified according to clinically available criteria as either hydrostatic edema or permeability edema to see if they could document differences among these groups. In control patients this ratio did not increase by more than seven units between the 20-minute and three-hour measurements. Of 18 patients classified by other routine clinical means as having hydrostatic pulmonary edema, 89% showed no increase in lung albumin accumulation. In 29 patients with permeability edema associated with the so-called adult respiratory distress syndrome, 31% showed evidence of net pulmonary albumin accumulation. These findings suggest that some patients otherwise classified as having hydrostatic edema have concomitant permeability changes in the microvasculature and that permeability edema represents a spectrum of endothelial damage.

Simple clinical means of documenting increased pulmonary endothelial permeability to protein

International Nuclear Information System (INIS)

Mishkin, F.S.; Niden, A.; Kumar, A.; Thomas, A.; Reese, I.C.; Vasinrapee, P.

1987-01-01

The authors investigated a simple method that can be used at the bedside for documenting the net accumulation of albumin in the lung. The technique employs measurement with a computer-linked gamma camera of the activity ratio in an area of the right lung compared with the same-sized area in the heart at 20 minutes and three hours following intravenous injection of technetium Tc 99m albumin. They applied this measurement to three groups of patients: a control group and patients with roentgenographic evidence of edema classified according to clinically available criteria as either hydrostatic edema or permeability edema to see if they could document differences among these groups. In control patients this ratio did not increase by more than seven units between the 20-minute and three-hour measurements. Of 18 patients classified by other routine clinical means as having hydrostatic pulmonary edema, 89% showed no increase in lung albumin accumulation. In 29 patients with permeability edema associated with the so-called adult respiratory distress syndrome, 31% showed evidence of net pulmonary albumin accumulation. These findings suggest that some patients otherwise classified as having hydrostatic edema have concomitant permeability changes in the microvasculature and that permeability edema represents a spectrum of endothelial damage

In vitro porcine blood-brain barrier model for permeability studies: pCEL-X software pKa(FLUX) method for aqueous boundary layer correction and detailed data analysis.

Science.gov (United States)

Yusof, Siti R; Avdeef, Alex; Abbott, N Joan

2014-12-18

In vitro blood-brain barrier (BBB) models from primary brain endothelial cells can closely resemble the in vivo BBB, offering valuable models to assay BBB functions and to screen potential central nervous system drugs. We have recently developed an in vitro BBB model using primary porcine brain endothelial cells. The model shows expression of tight junction proteins and high transendothelial electrical resistance, evidence for a restrictive paracellular pathway. Validation studies using small drug-like compounds demonstrated functional uptake and efflux transporters, showing the suitability of the model to assay drug permeability. However, one limitation of in vitro model permeability measurement is the presence of the aqueous boundary layer (ABL) resulting from inefficient stirring during the permeability assay. The ABL can be a rate-limiting step in permeation, particularly for lipophilic compounds, causing underestimation of the permeability. If the ABL effect is ignored, the permeability measured in vitro will not reflect the permeability in vivo. To address the issue, we explored the combination of in vitro permeability measurement using our porcine model with the pKa(FLUX) method in pCEL-X software to correct for the ABL effect and allow a detailed analysis of in vitro (transendothelial) permeability data, Papp. Published Papp using porcine models generated by our group and other groups are also analyzed. From the Papp, intrinsic transcellular permeability (P0) is derived by simultaneous refinement using a weighted nonlinear regression, taking into account permeability through the ABL, paracellular permeability and filter restrictions on permeation. The in vitro P0 derived for 22 compounds (35 measurements) showed good correlation with P0 derived from in situ brain perfusion data (r(2)=0.61). The analysis also gave evidence for carrier-mediated uptake of naloxone, propranolol and vinblastine. The combination of the in vitro porcine model and the software

Role of platelets in maintenance of pulmonary vascular permeability to protein

International Nuclear Information System (INIS)

Lo, S.K.; Burhop, K.E.; Kaplan, J.E.; Malik, A.B.

1988-01-01

The authors examined the role of platelets in maintenance of pulmonary vascular integrity by inducing thrombocytopenia in sheep using antiplatelet serum (APS). A causal relationship between thrombocytopenia and increase in pulmonary vascular permeability was established by platelet repletion using platelet-rich plasma (PRP). Sheep were chronically instrumented and lung lymph fistulas prepared to monitor pulmonary lymph flow (Q lym ). A balloon catheter was positioned in the left atrium to assess pulmonary vascular permeability to protein after raising the left atrial pressure (P la ). Thrombocytopenia was maintained for 3 days by daily intramuscular APS injections. In studies using cultured bovine pulmonary artery endothelial monolayers, transendothelia permeability of 125 I-labeled albumin was reduced 50 and 95%, respectively, when 2.5 x 10 7 or 5 x 10 7 platelets were added onto endothelial monolayers. However, addition of 5 x 10 6 platelets or 5 x 10 7 red blood cells did not reduce endothelial monolayer albumin permeability. Results indicate that platelets are required for the maintenance of pulmonary vascular permeability. Reduction in permeability appears to involve an interaction of platelets with the endothelium

Peritoneal Albumin and Protein Losses Do Not Predict Outcome in Peritoneal Dialysis Patients

NARCIS (Netherlands)

Balafa, Olga; Halbesma, Nynke; Struijk, Dirk G.; Dekker, Friedo W.; Krediet, Raymond T.

2011-01-01

Background and objectives Peritoneal clearance of albumin unlike the transport of small molecules is defined by both vascular surface area and size-selective permeability. Few studies have supported a positive correlation between peritoneal albumin loss and mortality. The aim of this study was to

Effect of desensitizing agents on dentin permeability.

Science.gov (United States)

Ishihata, Hiroshi; Kanehira, Masafumi; Nagai, Tomoko; Finger, Werner J; Shimauchi, Hidetoshi; Komatsu, Masashi

2009-06-01

To investigate the in vitro efficacy of two dentin desensitizing products at reducing liquid permeability through human dentin discs. The tested hypothesis was that the products, in spite of different chemical mechanisms were not different at reducing or eliminating flow through dentin discs. Dentin slices (1 mm thick) were prepared from 16 extracted human third molars and their permeability was indirectly recorded in a split chamber model, using a chemiluminescence technique, after EDTA treatment (control), after soaking with albumin, and after desensitizer application. Two products were studied: MS Coat, a self-curing resin-containing oxalate product, and Gluma Desensitizer, a glutaraldehyde/HEMA-based agent without initiator. The dentin slices were mounted between an upper chamber, filled with an aqueous solution of 1% potassium ferricyanide and 0.3% hydrogen peroxide, and a lower chamber filled with 1% sodium hydroxide solution and 0.02% luminol. The upper solution was pressurized, and upon contact with the luminol solution a photochemical signal was generated and recorded as a measure of permeability throughout two consecutive pressurizing cycles at 2.5 and 13 kPa (26 and 133 cm H2O), respectively. The permeability of the control and albumin-soaked samples was similarly high. After application of the desensitizing agents, dentin permeability was reduced to virtually zero at both pressure levels (P < 0.001).

Intimal permeability evaluated in a short-term organ culture of diabetic guinea pig aorta

International Nuclear Information System (INIS)

Schlosser, M.J.; Verlangieri, A.J.

1988-01-01

A novel short-term organ culture system was used to evaluate intimal permeability changes by measuring aortic [ 14 C]methylated albumin accumulation. Aortic plugs were removed from the upper thoracic aorta of male guinea pigs and maintained in serum-free media. The accumulation of [ 14 C]albumin in the intimal-medial layer was determined after a 5 h incubation. In preliminary studies, albumin recovered from intimal-injured aortic plugs was significantly greater than those from non-injured plugs. Aortic plugs from streptozotocin-treated guinea pigs, diabetic for 3 weeks, also accumulated significantly more [ 14 C]albumin than plugs from nondiabetic controls. Histological changes were not observed in the aorta of either the diabetic or control group. A strong significant inverse correlation was found between plasma ascorbic acid levels and [ 14 C]-activity recovered from aortic plugs. This study demonstrates a simple and rapid method for assessing aortic permeability changes under a well-defined in vitro system, and suggests that vascular permeability changes in the streptozotocin-diabetic guinea pig may be associated with an ascorbic acid deficit

Ethamsylate and lung permeability in ventilated immature newborn rabbits.

Science.gov (United States)

Amato, M; Sun, B; Robertson, B

1994-01-01

The leakage of proteins in the immature neonatal lung can reduce the effect of exogenous surfactant. The effect of ethamsylate, a more specific prostaglandin inhibitor than indomethacin and aspirin-like drugs, on alveolar albumin leak was studied in a group of 27 immature newborn rabbits (gestational age 27 days). A pilot study was carried out using 4 animals and low-dose ethamsylate (10 mg/kg). A second group of animals (n = 12) received at birth, by intravenous injection, ethamsylate (50 mg/kg) and 10% human albumin (7 ml/kg). Animals not receiving ethamsylate (n = 11) served as control group. After 30 min of artificial ventilation with standard tidal volume (10 ml/kg) the lungs were lavaged and the amount of human albumin in lung lavage fluid was determined by immunodiffusion. No statistically significant differences were found in lung-thorax compliance and vascular to alveolar albumin leak between ethamsylate-treated animals and controls (p > 0.5). However, there was a statistically significant negative correlation between protein leak and lung compliance (r = -0.41; p ethamsylate administration on neonatal lung permeability in the immature neonate confirming that lung permeability is inversely related to compliance.

Connexin 43 Expression on Peripheral Blood Eosinophils: Role of Gap Junctions in Transendothelial Migration

Directory of Open Access Journals (Sweden)

Harissios Vliagoftis

2014-01-01

Full Text Available Eosinophils circulate in the blood and are recruited in tissues during allergic inflammation. Gap junctions mediate direct communication between adjacent cells and may represent a new way of communication between immune cells distinct from communication through cytokines and chemokines. We characterized the expression of connexin (Cx43 by eosinophils isolated from atopic individuals using RT-PCR, Western blotting, and confocal microscopy and studied the biological functions of gap junctions on eosinophils. The formation of functional gap junctions was evaluated measuring dye transfer using flow cytometry. The role of gap junctions on eosinophil transendothelial migration was studied using the inhibitor 18-a-glycyrrhetinic acid. Peripheral blood eosinophils express Cx43 mRNA and protein. Cx43 is localized not only in the cytoplasm but also on the plasma membrane. The membrane impermeable dye BCECF transferred from eosinophils to epithelial or endothelial cells following coculture in a dose and time dependent fashion. The gap junction inhibitors 18-a-glycyrrhetinic acid and octanol did not have a significant effect on dye transfer but reduced dye exit from eosinophils. The gap junction inhibitor 18-a-glycyrrhetinic acid inhibited eosinophil transendothelial migration in a dose dependent manner. Thus, eosinophils from atopic individuals express Cx43 constitutively and Cx43 may play an important role in eosinophil transendothelial migration and function in sites of inflammation.

Dual effect of insulin on plasma volume and transcapillary albumin transport

DEFF Research Database (Denmark)

Hilsted, J; Christensen, N J

1992-01-01

vascular dilatation and increased muscle sympathetic nerve activity during a euglycaemic glucose clamp. During similar conditions insulin increased the transcapillary escape rate of albumin and reduced plasma volume. Insulin has also an indirect effect on vascular permeability during hypoglycaemia, which...... is mediated by the increase in plasma adrenaline. Adrenaline infusion increased haematocrit and decreased plasma volume and intravascular albumin mass. In contrast to insulin adrenaline did not increase the transcapillary escape rate of albumin. Total autonomic blockade during insulin-induced hypoglycaemia...... abolished the increase in haematocrit, but did not influence the decrease in plasma volume and the increase in the transcapillary escape rate of albumin. Insulin administration may also increase urinary albumin excretion, and this effect was observed during a euglycaemic clamp. The mechanism of the increase...

Cigarette smoke extract increases albumin flux across pulmonary endothelium in vitro

International Nuclear Information System (INIS)

Holden, W.E.; Maier, J.M.; Malinow, M.R.

1989-01-01

Cigarette smoking causes lung inflammation, and a characteristic of inflammation is an increase in vascular permeability. To determine if cigarette smoke could alter endothelial permeability, we studied flux of radiolabeled albumin across monolayers of porcine pulmonary artery endothelium grown in culture on microporous membranes. Extracts (in either dimethylsulfoxide or phosphate-buffered saline) of cigarette smoke in a range estimate of concentrations simulating cigarette smoke exposure to the lungs in vivo caused a dose-dependent increase in albumin flux that was dependent on extracellular divalent cations and associated with polymerization of cellular actin. The effect was reversible, independent of the surface of endothelial cells exposed (either luminal or abluminal), and due primarily to components of the vapor phase of smoke. The effects occurred without evidence of cell damage, but subtle morphological changes were produced by exposure to the smoke extracts. These findings suggest that cigarette smoke can alter permeability of the lung endothelium through effects on cytoskeletal elements

Albuminuria and overall capillary permeability of albumin in acute altitude hypoxia

DEFF Research Database (Denmark)

Hansen, J M; Olsen, Niels Vidiendal; Feldt-Rasmussen, B

1994-01-01

The mechanism of proteinuria at high altitude is unclear. Renal function and urinary excretion rate of albumin (Ualb) at rest and during submaximal exercise and transcapillary escape rate of 125I-labeled albumin (TERalb) were investigated in 12 normal volunteers at sea level and after rapid...... and passive ascent to 4,350 m. The calcium antagonist isradipine (5 mg/day; n = 6) or placebo (n = 6) was administered to abolish hypoxia-induced rises in blood pressure. Lithium clearance and urinary excretion of beta 2-microglobulin were used to evaluate renal tubular function. High altitude increased Ualb...... from 2.8 to > 5.0 micrograms/min in both groups (P high altitude significantly increased filtration fraction (P

Effect of platelet activating factor on endothelial permeability to plasma macromolecules

International Nuclear Information System (INIS)

Handley, D.A.; Arbeeny, C.M.; Lee, M.L.; Van Valen, R.G.; Saunders, R.N.

1984-01-01

The effect of intrajugular administration of platelet activating factor (PAF-C16) on vascular permeability was examined in the guinea pig. To examine the loss of selective endothelial permeability, the extravasative effect of PAF was assessed by monitoring hemoconcentration and the plasma loss of 125 I-albumin (6.7 nm), 125 I-low density lipoproteins (22.0 nm) or 125 I-very low density lipoproteins (62.1 nm). Extravasation was dose-dependent and began 1 min after PAF administration, continuing for 5-7 min. During extravasation, there was no evidence for selective plasma retention of any of the labeled plasma tracers, as measured by plasma radioactivity. These results suggest that PAF-induced extravasation is dose-dependent, with increases in vascular permeability sufficient to permit similar plasma efflux rates of albumin, low density lipoproteins and very low density lipoproteins

Isotopic test of capillary permeability to albumin in diabetic patients: effects of hypertension, microangiopathy, and duration of diabetes

International Nuclear Information System (INIS)

Valensi, P.; Attali, J.R.; Behar, A.; Sebaoun, J.

1987-01-01

Capillary permeability to albumin (CPA) was studied by performing an isotopic noninvasive test with venous compression on 87 nonselected diabetics with no edema, no cardiac failure, and no peripheral vascular disease. Excessive albumin retention (AR greater than or equal to 8%) ten minutes after removal of the compression was found in 27 patients (31%). The radioactivity disappearance curve was then analyzed using the Fast Fourier Transform (FFT). An abnormal isotopic CPA test was thus found in at least 45 out of the 87 patients. The prevalence of an abnormal test was not different in type 1 and type 2 diabetics. We studied the independent effects of hypertension, presence of specific clinical signs of microangiopathy (retinopathy and/or significant proteinuria), and duration of diabetes. Among diabetics free of specific clinical signs of microangiopathy, the prevalence of an AR greater than or equal to 8% was significantly higher in those with hypertension (11/19) than in those with normal blood pressure (2/28) and in nondiabetic hypertensive patients (0/16). Among normotensive diabetics, the prevalence of an abnormal test was higher, but not significantly, in patients with specific clinical signs of microangiopathy (8/11) than in those free of them (7/18). Seven normotensive diabetics without specific clinical signs of microangiopathy had an abnormal test; five of them had had diabetes for more than five years. The prevalence of diabetes of more than five years duration was significantly higher in patients with an abnormal test (35/45) than in normotensive diabetics free of specific clinical signs of microangiopathy with a normal test (4/11)

Normal overall leakiness of microvasculature for albumin in patients with chronic obstructive lung disease (COLD)

DEFF Research Database (Denmark)

Kok-Jensen, A; Henriksen, Jens Henrik Sahl

1984-01-01

The overall extravasation rate of albumin, TER (i.e. the fraction of the intravascular albumin mass (IVM) passing into, and during steady state returning from, the extravascular space per unit time) was determined from the disappearance of i.v. injected radioiodinated serum albumin in seven...... controls 6.0% IVM/h (range 4.3-7.4), indicating that no significant change in microvascular leakiness to albumin could be found in patients with COLD. Thus, the results bring no support to a generally increased microvascular permeability to proteins in patients with COLD....

Hypoxia/reoxygenation increases the permeability of endothelial cell monolayers: Role of oxygen radicals

International Nuclear Information System (INIS)

Inauen, W.; Payne, D.K.; Kvietys, P.R.; Granger, D.N.

1990-01-01

We assessed the effect of hypoxia/reoxygenation on 14C-albumin flux across endothelial monolayers. Cultured bovine pulmonary artery endothelial cells were grown to confluence on nitrocellulose filters (pore size 12 microns). The endothelialized filters were mounted in Ussing-type chambers which were filled with cell culture medium (M 199). Equimolar amounts (33 nM) of 14C-labeled and unlabeled albumin were added to the hot and cold chambers, respectively. The monolayers were then exposed to successive periods (90 min) of normoxia (pO2 145 mmHg), hypoxia (pO2 20 mmHg), and reoxygenation (pO2 145 mmHg). A gas bubbling system was used to control media pO2 and to ensure adequate mixing. Four aliquots of culture media were taken during each period in order to calculate the 14C-albumin permeability across the endothelialized filter. In some experiments, either the xanthine oxidase inhibitor, oxypurinol (10 microM), or superoxide dismutase (600 U/mL), was added to the media immediately prior to the experiments. As compared to the normoxic control period, albumin permeability was 1.5 times higher during hypoxia (p less than 0.01) and 2.3 times higher during reoxygenation (p less than 0.01). The reoxygenation-induced increase in albumin permeability was prevented by either oxypurinol or superoxide dismutase. These data indicate that xanthine oxidase-derived oxygen radicals contribute to the hypoxia/reoxygenation-induced endothelial cell dysfunction. The altered endothelial barrier function induced by hypoxia/reoxygenation is consistent with the microvascular dysfunction observed following reperfusion of ischemic tissues

A Cdc42/RhoA regulatory circuit downstream of glycoprotein Ib guides transendothelial platelet biogenesis

DEFF Research Database (Denmark)

Dütting, Sebastian; Gaits-Iacovoni, Frederique; Stegner, David

2017-01-01

Blood platelets are produced by large bone marrow (BM) precursor cells, megakaryocytes (MKs), which extend cytoplasmic protrusions (proplatelets) into BM sinusoids. The molecular cues that control MK polarization towards sinusoids and limit transendothelial crossing to proplatelets remain unknown...

Transcriptional profiling of human monocytes identifies the inhibitory receptor CD300a as regulator of transendothelial migration.

Directory of Open Access Journals (Sweden)

Sharang Ghavampour

Full Text Available Local inflammatory responses are characterized by the recruitment of circulating leukocytes from the blood to sites of inflammation, a process requiring the directed migration of leukocytes across the vessel wall and hence a penetration of the endothelial lining. To identify underlying signalling events and novel factors involved in these processes we screened for genes differentially expressed in human monocytes following their adhesion to and passage through an endothelial monolayer. Functional annotation clustering of the genes identified revealed an overrepresentation of those associated with inflammation/immune response, in particular early monocyte to macrophage differentiation. Among the gene products so far not implicated in monocyte transendothelial migration was the inhibitory immune receptor CD300a. CD300a mRNA and protein levels were upregulated following transmigration and engagement of the receptor by anti-CD300a antibodies markedly reduced monocyte transendothelial migration. In contrast, siRNA mediated downregulation of CD300a in human monocytes increased their rate of migration. CD300a colocalized and cosedimented with actin filaments and, when activated, caused F-actin cytoskeleton alterations. Thus, monocyte transendothelial migration is accompanied by an elevation of CD300a which serves an inhibitory function possibly required for termination of the actual transmigration.

In vitro dentin permeability after application of Gluma® desensitizer as aqueous solution or aqueous fumed silica dispersion

Directory of Open Access Journals (Sweden)

Hiroshi Ishihata

2011-04-01

Full Text Available OBJECTIVES: To assess and to compare the effects of Gluma® Desensitizer (GDL with an experimental glutaraldehyde and HEMA containing fumed silica dispersion (GDG on dentin permeability using a chemiluminous tracer penetration test. MATERIAL AND METHODS: Twenty disc-shaped dentin specimens were dissected from extracted human third molars. The dentin specimens were mounted in a split chamber device for determination of permeability under liquid pressure using a photochemical method. Ten specimens were randomly selected and allocated to the evaluation groups Gluma® Desensitizer as aqueous solution and glutaraldehyde/HEMA as fumed silica dispersion, respectively. Dentin disc permeability was determined at two pressure levels after removal of smear with EDTA, after albumin soaking, and after application of the desensitizing agents. Two desensitizer-treated and rinsed specimens of each group were examined by scanning electron microscopy (SEM for surface remnants. RESULTS: Comparatively large standard deviations of the mean EDTA reference and albumin soaked samples permeability values refected the differences of the dentin substrates. The mean chemiluminescence values of specimen treated with GDL and GDG, respectively, were signifcantly reduced after topical application of the desensitizing agents on albumin-soaked dentin. The effects of GDL and GDG on permeability were not signifcantly different. Treated specimens showed no surface remnants after rinsing. CONCLUSIONS: The experimental desensitizer gel formulation reduced dentin permeability as effectively as the original Gluma® Desensitizer solution.

Comparison between PVHIS on the MRI and the permeability of brain blood vessels in elderly patients

International Nuclear Information System (INIS)

Yamaguchi, Katsuhiko; Tanaka, Yuriko; Kubo, Hideki; Takagi, Yasushi; Tachikawa, Shinzo; Katsunuma, Hideyo.

1989-01-01

The degree of PVHIS (periventricular high intensity signal) on the MRI was composed with the permeability of brain blood vessels using the cerebrospinal fluid (CSF)/serum ratio for albumin, and the CSF/serum ratio for IgG in elderly patients. The 47 elderly patients (mean age=79.9) were divided into three groups: (1) Mild group (20 cases, M:6, F:14, mean age=75.8), (2) Moderate group (18 cases, M:7, F:11, mean age=82.6), (3) Severe group (9 cases, M:2, F:7, mean age=82.9), in accordance with the degree of PVHIS on the MRI. The MRI was operated at a field strength of 0.22 tesla. The pulse sequence (used on all patients) had a repetition times (TR) of 2,000 msec and a time to echo (TE) of 40 msec. The levels of albumin and IgG in the serum and CSF were measured. The CSF/serum ratio for albumin was used of analyze the permeability of the brain blood vessels in each group. There was no significant difference in the level of the serum albumin, the CSF albumin, the serum IgG, the CSF IgG and the CSF/serum ratio for IgG among the three groups. The same was found to be true for the IgG index which indicates the synthesis of immunoglobulin in the central nervous system. However, there was a statistically significant difference (p<0.05) in the CSF/serum ratio for albumin between groups (1) and (3). The increased CSF/serum ratio for albumin in the severe group indicated there were confluent lesions involving the entire extent of the periventriular white matter on the MRI. This suggested an increased permeability of brain blood vessels which revealed the dysfunction of the blood brain barrier due to affected cerebral endothelial cells in capillaries. (author)

Regulation of endothelial cell shape and monolayer permeability by atrial natriuretic peptide

International Nuclear Information System (INIS)

Lofton-Day, C.E.

1989-01-01

Atrial natriuretic peptide (ANP), considered to be an important regulator of intravascular fluid volume, binds specifically to receptors on endothelial cells. In this study, the role of ANP-specific binding was investigated by examining the effect of ANP on the morphology and macromolecular permeability of monolayer cultures of bovine aortic endothelial cells. ANP alone had no observable effect on the monolayers. However, incubation of monolayers with ANP antagonized thrombin- or glucose oxidase-induced cell shape changes and intercellular gap formation. ANP pretreatment also opposed the effect of thrombin and glucose oxidase on actin filament distribution as observed by rhodamine-phalloidin staining and digital image analysis of F0actin staining. In addition, ANP reversed cell shape changes and cytoskeletal alterations induced by thrombin treatment but did not reverse alternations induced by glucose oxidase treatment. ANP significantly reduced increases in monolayer permeability to albumin resulting from thrombin or glucose oxidases treatment. Thrombin caused a 2-fold increase in monolayer permeability to 125 I-labeled albumin, which was abolished by 10 -8 -10 -6 M ANP pretreatment. Glucose oxidase caused similar increases in permeability and was inhibited by ANP at slightly shorter time periods

Hydrogen sulfide metabolism regulates endothelial solute barrier function

Directory of Open Access Journals (Sweden)

Shuai Yuan

2016-10-01

Full Text Available Hydrogen sulfide (H2S is an important gaseous signaling molecule in the cardiovascular system. In addition to free H2S, H2S can be oxidized to polysulfide which can be biologically active. Since the impact of H2S on endothelial solute barrier function is not known, we sought to determine whether H2S and its various metabolites affect endothelial permeability. In vitro permeability was evaluated using albumin flux and transendothelial electrical resistance. Different H2S donors were used to examine the effects of exogenous H2S. To evaluate the role of endogenous H2S, mouse aortic endothelial cells (MAECs were isolated from wild type mice and mice lacking cystathionine γ-lyase (CSE, a predominant source of H2S in endothelial cells. In vivo permeability was evaluated using the Miles assay. We observed that polysulfide donors induced rapid albumin flux across endothelium. Comparatively, free sulfide donors increased permeability only with higher concentrations and at later time points. Increased solute permeability was associated with disruption of endothelial junction proteins claudin 5 and VE-cadherin, along with enhanced actin stress fiber formation. Importantly, sulfide donors that increase permeability elicited a preferential increase in polysulfide levels within endothelium. Similarly, CSE deficient MAECs showed enhanced solute barrier function along with reduced endogenous bound sulfane sulfur. CSE siRNA knockdown also enhanced endothelial junction structures with increased claudin 5 protein expression. In vivo, CSE genetic deficiency significantly blunted VEGF induced hyperpermeability revealing an important role of the enzyme for barrier function. In summary, endothelial solute permeability is critically regulated via exogenous and endogenous sulfide bioavailability with a prominent role of polysulfides.

Imaging alveolar-capillary permeability in experimental respiratory distress syndrome

International Nuclear Information System (INIS)

Suzuki, T.; Watanabe, S.; Wagner, H.N.; Swift, D.L.; Proctor, D.F.

1982-01-01

Pulmonary edema can be induced in dogs by low doses of oleic acid (20 μl/kg) given intravenously, simulating the adult respiratory distress syndrome (ARDS). Alveolar-capillary permeability was measured in dogs, using sup(99m)Tc-DTPA and sup(99m)Tc-albumin fine aerosols produced by a newly designed separator. This separator eliminates the effect of mucociliary movement on aerosol clearance. The small molecular-laden aerosol particles were cleared in the order: sup(99m)-TcO 4 - , sup(99m)Tc-DTPA, and sup(99m)Tc-disofenin; the Tsub(1/2) of lung clearance correlated with molecular sizes. Experimental ARDS increased the lung clearance of sup(99m)Tc-DTPA. Lung clearance of large molecule (sup(99m)Tc-albumin) laden aerosol particles was not accelerated in the ARDS model. Inhalation with fine aerosols revealed increased alveolar permeability in the ARDS model without any change of cardiac output

Renal albumin excretion: twin studies identify influences of heredity, environment, and adrenergic pathway polymorphism

DEFF Research Database (Denmark)

Rao, Fangwen; Wessel, Jennifer; Wen, Gen

2007-01-01

biosynthesis (tyrosine hydroxylase), catabolism (monoamine oxidase A), storage/release (chromogranin A), receptor target (dopamine D1 receptor), and postreceptor signal transduction (sorting nexin 13 and rho kinase). Epistasis (gene-by-gene interaction) occurred between alleles at rho kinase, tyrosine...... hydroxylase, chromogranin A, and sorting nexin 13. Dopamine D1 receptor polymorphism showed pleiotropic effects on both albumin and dopamine excretion. These studies establish new roles for heredity and environment in albumin excretion. Urinary excretions of albumin and catecholamines are highly heritable......, and their parallel suggests adrenergic mediation of early glomerular permeability alterations. Albumin excretion is influenced by multiple adrenergic pathway genes and is, thus, polygenic. Such functional links between adrenergic activity and glomerular injury suggest novel approaches to its prediction, prevention...

Study of albumin and fibrinogen membranes formed by interfacial crosslinking using microfluidic flow

Energy Technology Data Exchange (ETDEWEB)

Chang Hong; Khan, Rachel; Rong, Zimei; Vadgama, Pankaj [IRC in Biomedical Materials, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Sapelkin, Andrei, E-mail: p.vadgama@qmul.ac.u [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)

2010-09-15

Microfluidics enables scale reduction in sample volume with obvious benefits for reagent conservation. In contrast to conventional macro-scale flow, microfluidics also offers unprecedented control over flow dynamics. In particular, laminar flow is readily achieved, allowing for new analytical and synthetic strategies. Here, two parallel flows of buffer and xylene were used to create a stable liquid-liquid interface within linear micro-channels. These, respectively, carried protein (albumin or fibrinogen) and an acyl chloride to effect protein crosslinking. This created robust, micro-membranes at the interface that bisected the fluid channel. Membrane formation was self-limiting, with fibrinogen membranes showing greater solute permeability than albumin, based on dye transport (Ponceau S, Meldola Blue). The crosslinker isophthaloyl dichloride led to thinner, less permeable membranes than terephthaloyl chloride. Larger surface area membranes formed at a static liquid-liquid interface served as a more physically accessible model and allowed precise electrochemical determination of acetaminophen, catechol and peroxide diffusion coefficients, which confirmed the greater fibrinogen permeability. Scanning electron microscopy (SEM) of the membranes also indicated a higher population of discrete nanopores at the fibrinogen surface. A crosslinking pH had a strong effect on overall permeability. Adhesion of B50 neuronal cells was demonstrated, and it is proposed that the membranes could facilitate cell growth through bidirectional nutrient supply in a micrbioreactor format.

The use of albumin in the complications of cirrhosis: evidence and future perspectives

Directory of Open Access Journals (Sweden)

Alessandra Tovoli

2013-07-01

Full Text Available The therapeutic use of albumin in cirrhosis dates back to the 50s, when hypoalbuminemia was thought to play a crucial role in the pathophysiology of ascites. Today, while its efficacy in the treatment of ascites is still under investigation, it has been proved that albumin is able to improve patient outcome and survival in some specific complications of cirrhosis, such as the prevention of post-paracentesis circulatory dysfunction and the treatment of spontaneous bacterial peritonitis and hepatorenal syndrome. Beside its oncotic power, albumin carries other biological properties, the so called non-oncotic properties, including transportation and detoxification of several molecules, free radical scavenging, modulation of vascular permeability, activity on the immune system and on the haemostatic balance. Some experimental evidences indicate that not only albumin concentration but also its function is reduced in patients with cirrhosis. However, the clinical implications of such functional abnormalities is still unclear. We here present the available evidence on the use of albumin in cirrhosis and future perspectives.http://dx.doi.org/10.7175/rhc.v4i3.659

Renal type a intercalated cells contain albumin in organelles with aldosterone-regulated abundance.

Directory of Open Access Journals (Sweden)

Thomas Buus Jensen

Full Text Available 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.

Immunologic relationships of human serum albumin, macroaggregated albumin, and albumin microspheres

International Nuclear Information System (INIS)

Stang, P.C.; Roelands, J.F.; Cohen, P.

1975-01-01

Antigenic relationships of NSA (normal serum albumin), MAA (macroaggregated albumin), and HAM (human albumin microspheres) were determined in vivo in guinea pigs and in vitro in gel diffusion plates. Results showed that HAM could sensitize but seldom elicit anaphylaxis when used to challenge guinea pigs. In contrast, NSA and MAA were strong sensitizing antigens and inducers of anaphylaxis. The relative inability of HAM to induce anaphylaxis suggests that during production of the microspheres from soluble albumin, antigenic determinants of albumin may be altered or masked. Consequently, these determinants may be less available to react with antibody at the tissue sites

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

Directory of Open Access Journals (Sweden)

Levitt DG

2016-07-01

Full Text Available David G Levitt,1,* Michael D Levitt2,* 1Department of Integrative Biology and Physiology, University of Minnesota, 2Research Service, Veterans Affairs Medical Center, Minneapolis, MN, USA *These authors contributed equally to this work Abstract: 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

Water-Permeable Dialysis Membranes for Multi-Layered Micro Dialysis System

Directory of Open Access Journals (Sweden)

Naoya eTo

2015-06-01

Full Text Available This paper presents the development of water-permeable dialysis membranes that are suitable for an implantable microdialysis system that does not use dialysis fluid. We developed a microdialysis system integrating microfluidic channels and nanoporous filtering membranes made of polyethersulfone (PES, aiming at a fully implantable system that drastically improves the quality of life of patients. Simplicity of the total system is crucial for the implantable dialysis system, where the pumps and storage tanks for the dialysis fluid pose problems. Hence, we focus on hemofiltration, which does not require the dialysis fluid but water-permeable membranes. We investigated the water-permeability of the PES membrane with respect to the concentrations of the PES, the additives, and the solvents in the casting solution. Sufficiently water-permeable membranes were found through in vitro experiments using whole bovine blood. The filtrate was verified to have the concentrations of low-molecular-weight molecules, such as sodium, potassium, urea, and creatinine, while proteins, such as albumin, were successfully blocked by the membrane. We conducted in vivo experiments using rats, where the system was connected to the femoral artery and jugular vein. The filtrate was successfully collected without any leakage of blood inside the system and it did not contain albumin but low-molecular-weight molecules whose concentrations were identical to those of the blood. The rat model with renal failure showed 100% increase of creatinine in 5 h, while rats connected to the system showed only a 7.4% increase, which verified the effectiveness of the proposed microdialysis system.

Dextran/Albumin hydrogel sealant for Dacron(R) vascular prosthesis.

Science.gov (United States)

Lisman, Anna; Butruk, Beata; Wasiak, Iga; Ciach, Tomasz

2014-05-01

In this paper, the authors describe a novel type of hydrogel coating prepared from the copolymer of human serum albumin and oxidized dextran. The material was designed as a hydrogel sealant for polyester (Dacron®)-based vascular grafts. Dextran was chosen as a coating material due to its anti-thrombogenic properties. Prepared hydrogels were compared with similar, already known biomaterial made from gelatine with the same cross-linking agent. Obtained hydrogels, prepared from various ratios of oxidized dextran/albumin or oxidized dextran/gelatine, showed different cross-linking densities, which caused differences in swelling, degradation rate and mechanical properties. Permeability tests confirmed the complete tightness of the hydrogel-modified prosthesis. Results showed that application of the hydrogel coating provided leakage-free prosthesis and eliminated the need of pre-clotting.

Cortactin deficiency is associated with reduced neutrophil recruitment but increased vascular permeability in vivo.

Science.gov (United States)

Schnoor, Michael; Lai, Frank P L; Zarbock, Alexander; Kläver, Ruth; Polaschegg, Christian; Schulte, Dörte; Weich, Herbert A; Oelkers, J Margit; Rottner, Klemens; Vestweber, Dietmar

2011-08-01

Neutrophil extravasation and the regulation of vascular permeability require dynamic actin rearrangements in the endothelium. In this study, we analyzed in vivo whether these processes require the function of the actin nucleation-promoting factor cortactin. Basal vascular permeability for high molecular weight substances was enhanced in cortactin-deficient mice. Despite this leakiness, neutrophil extravasation in the tumor necrosis factor-stimulated cremaster was inhibited by the loss of cortactin. The permeability defect was caused by reduced levels of activated Rap1 (Ras-related protein 1) in endothelial cells and could be rescued by activating Rap1 via the guanosine triphosphatase (GTPase) exchange factor EPAC (exchange protein directly activated by cAMP). The defect in neutrophil extravasation was caused by enhanced rolling velocity and reduced adhesion in postcapillary venules. Impaired rolling interactions were linked to contributions of β(2)-integrin ligands, and firm adhesion was compromised by reduced ICAM-1 (intercellular adhesion molecule 1) clustering around neutrophils. A signaling process known to be critical for the formation of ICAM-1-enriched contact areas and for transendothelial migration, the ICAM-1-mediated activation of the GTPase RhoG was blocked in cortactin-deficient endothelial cells. Our results represent the first physiological evidence that cortactin is crucial for orchestrating the molecular events leading to proper endothelial barrier function and leukocyte recruitment in vivo.

Quantification of osmotic water transport in vivo using fluorescent albumin.

Science.gov (United States)

Morelle, Johann; Sow, Amadou; Vertommen, Didier; Jamar, François; Rippe, Bengt; Devuyst, Olivier

2014-10-15

Osmotic water transport across the peritoneal membrane is applied during peritoneal dialysis to remove the excess water accumulated in patients with end-stage renal disease. The discovery of aquaporin water channels and the generation of transgenic animals have stressed the need for novel and accurate methods to unravel molecular mechanisms of water permeability in vivo. Here, we describe the use of fluorescently labeled albumin as a reliable indicator of osmotic water transport across the peritoneal membrane in a well-established mouse model of peritoneal dialysis. After detailed evaluation of intraperitoneal tracer mass kinetics, the technique was validated against direct volumetry, considered as the gold standard. The pH-insensitive dye Alexa Fluor 555-albumin was applied to quantify osmotic water transport across the mouse peritoneal membrane resulting from modulating dialysate osmolality and genetic silencing of the water channel aquaporin-1 (AQP1). Quantification of osmotic water transport using Alexa Fluor 555-albumin closely correlated with direct volumetry and with estimations based on radioiodinated ((125)I) serum albumin (RISA). The low intraperitoneal pressure probably accounts for the negligible disappearance of the tracer from the peritoneal cavity in this model. Taken together, these data demonstrate the appropriateness of pH-insensitive Alexa Fluor 555-albumin as a practical and reliable intraperitoneal volume tracer to quantify osmotic water transport in vivo. Copyright © 2014 the American Physiological Society.

Albumin nanoparticles with synergistic antitumor efficacy against metastatic lung cancers.

Science.gov (United States)

Kim, Bomi; Seo, Bohyung; Park, Sanghyun; Lee, Changkyu; Kim, Jong Oh; Oh, Kyung Taek; Lee, Eun Seong; Choi, Han-Gon; Youn, Yu Seok

2017-10-01

Albumin nanoparticles are well-known as effective drug carriers used to deliver hydrophobic chemotherapeutic agents. Albumin nanoparticles encapsulating curcumin and doxorubicin were fabricated using slightly modified nanoparticle albumin-bound (nab™) technology, and the synergistic effects of these two drugs were examined. Albumin nanoparticles encapsulating curcumin, doxorubicin, and both curcumin and doxorubicin were prepared using a high pressure homogenizer. The sizes of albumin nanoparticles were ∼130nm, which was considered to be suitable for the EPR (enhanced permeability and retention) effect. Albumin nanoparticles gradually released drugs over a period of 24h without burst effect. To confirm the synergistic effect of two drugs, in vitro cytotoxicity assay was performed using B16F10 melanoma cells. The cytotoxic effect on B16F10 melanoma cells was highest when co-treated with both curcumin and doxorubicin compared to single treatment of either curcumin and doxorubicin. The combined index calculated by medium-effect equation was 0.6069, indicating a synergistic effect. Results of confocal laser scanning microscopy and fluorescence-activated cell sorting corresponded to results from an in vitro cytotoxicity assay, indicating synergistic cytotoxicity induced by both drugs. A C57BL/6 mouse model induced by B16F10 lung metastasis was used to study in vivo therapeutic effects. When curcumin and doxorubicin were simultaneously treated, the metastatic melanoma mass in the lungs macroscopically decreased compared to curcumin or doxorubicin alone. Albumin nanoparticles encapsulating two anticancer drugs were shown to have an effective therapeutic result and would be an excellent way to treat resistant lung cancers. Copyright © 2017 Elsevier B.V. All rights reserved.

Passage of albumin from the middle ear to the inner ear in otitis media in the chinchilla

International Nuclear Information System (INIS)

Goldberg, B.; Goycoolea, M.V.; Schleivert, P.M.; Shea, D.; Schachern, P.; Paparella, M.M.; Carpenter, A.M.

1981-01-01

A study of the permeability of the middle ear-inner ear interface for macromolecules was carried out in chinchillas with open and obstructed eustachian tubes utilizing tritiated human serum albumin and immunoelectrophoresis. Tritiated albumin was placed in the round window niche area or normal animals and animals in which the eustachian tubes had been obstructed for 24 hours or 14 days. The tritiated albumin was allowed to remain in the middle ear cavity for 24 hours, Samples of middle ear effusion, perilymph, blood and cerebrospinal fluid were collected and measured for radioactivity. Radioactivity was demonstrated in the perilymph. Samples of middle ear effusions and perilymph were also studied by immunoelectrophoresis with goat antihuman albumin. Albumin placed in the round window niche of an experimental animal could be recovered unchanged in the perilymph. The results suggest a pathophysiologic explanation for the association of otitis media and sensorineural hearing loss or endolymphatic hydrops

Live Brugia malayi microfilariae inhibit transendothelial migration of neutrophils and monocytes.

Directory of Open Access Journals (Sweden)

Jan-Hendrik Schroeder

Full Text Available Lymphatic filariasis is a major tropical disease caused by the parasite Brugia malayi. Microfilariae (Mf circulate in the peripheral blood for 2-3 hours in synchronisation with maximal feeding of the mosquito vector. When absent from the peripheral blood, Mf sequester in the capillaries of the lungs. Mf are therefore in close contact with vascular endothelial cells (EC and may induce EC immune function and/or wound repair mechanisms such as angiogenesis. In this study, Mf were co-cultured with human umbilical vein EC (HUVEC or human lung microvascular EC (HLMVEC and the transendothelial migration of leukocyte subsets was analysed. In addition, the protein and/or mRNA expression of chemokine, cytokine and angiogenic mediators in endothelial cells in the presence of live microfilariae were measured by a combination of cDNA arrays, protein arrays, ELISA and fluorescence antibody tests.Surprisingly, our findings indicate that Mf presence partially blocked transendothelial migration of monocytes and neutrophils, but not lymphocytes. However, Mf exposure did not result in altered vascular EC expression of key mediators of the tethering stage of extravasation, such as ICAM-1, VCAM-1 and various chemokines. To further analyse the immunological function of vascular EC in the presence of Mf, we measured the mRNA and/or protein expression of a number of pro-inflammatory mediators. We found that expression levels of the mediators tested were predominantly unaltered upon B. malayi Mf exposure. In addition, a comparison of angiogenic mediators induced by intact Mf and Wolbachia-depleted Mf revealed that even intact Mf induce the expression of remarkably few angiogenic mediators in vascular EC. Our study suggests that live microfilariae are remarkably inert in their induction and/or activation of vascular cells in their immediate local environment. Overall, this work presents important insights into the immunological function of the vascular endothelium during

Permeability of the arterial endothelium of spontaneously hypertensive rats to plasma macromolecules

International Nuclear Information System (INIS)

Yurukova, Z.B.; Georgiev, P.G.

1979-01-01

By means of vascular labelling technique at cellular level, the permeability of the arterial endothelium of spontaneously hypertensive rats has been studied. For this purpose colloidal carbon and plasma lipoproteins were introduced into the jugular vein of the animals. Material for light- and electron-microscopic and radioautographic examinations was taken from the thoracic and abdominal parts of the aorta. The results show that in long-term hypertension substances from plasma enter the aortic wall in increased amounts through two main pathways. First, through the selective physiological pathways of transendothelial transport (through cell junctions and vesicular transport) and secondly, through discontinuities of the endothelial lining (separation of the intercellular junctions, areas of loss of one to several endothelial cells). The alteration of the arterial endothelium barrier function in chronic hypertension seems to be an important mechanism for the progression of hypertensive arterial lesions. (A.B.)

A discussion of serum albumin level in advanced-stage hepatocellular carcinoma: a medical oncologist's perspective.

Science.gov (United States)

Tanriverdi, Ozgur

2014-11-01

Hepatocellular carcinoma is the most common primary malignant tumor of the liver, and it is particularly prevalent in East and Southeast Asia. With surgical and/or local interventional treatment methods, survival rates for early-stage hepatocellular cancers have increased. However, it is not yet clear which staging systems are more applicable in hepatocellular carcinoma. Serum albumin level is already being used as a criterion in most staging systems. Albumin is an important serum protein in human bodily functions, but only 5 % of the daily amount needed is synthesized by the liver. The serum albumin level is affected by multifactorial situations, including capillary permeability, drugs, liver insufficiency, inflammation and/or infections, dehydration or overhydration, protein loosing disorders, and decreased nutrition intake in anorexia-malnutrition syndrome and cancer cachexia. Because of this complex situation, serum albumin level may affect many staging systems for hepatocellular carcinoma by leading to false-negative results. In this paper, the statuses of current staging systems are reviewed, and possible negative events regarding the serum albumin levels found in these staging systems are discussed.

Novel ex vivo culture method for human monocytes uses shear flow to prevent total loss of transendothelial diapedesis function.

Science.gov (United States)

Tsubota, Yoshiaki; Frey, Jeremy M; Raines, Elaine W

2014-01-01

Monocyte recruitment to inflammatory sites and their transendothelial migration into tissues are critical to homeostasis and pathogenesis of chronic inflammatory diseases. However, even short-term suspension culture of primary human monocytes leads to phenotypic changes. In this study, we characterize the functional effects of ex vivo monocyte culture on the steps involved in monocyte transendothelial migration. Our data demonstrate that monocyte diapedesis is impaired by as little as 4 h culture, and the locomotion step is subsequently compromised. After 16 h in culture, monocyte diapedesis is irreversibly reduced by ∼90%. However, maintenance of monocytes under conditions mimicking physiological flow (5-7.5 dyn/cm²) is sufficient to reduce diapedesis impairment significantly. Thus, through the application of shear during ex vivo culture of monocytes, our study establishes a novel protocol, allowing functional analyses of monocytes not currently possible under static culture conditions. These data further suggest that monocyte-based therapeutic applications may be measurably improved by alteration of ex vivo conditions before their use in patients.

Dissociation of changes in the permeability of the blood-brain barrier from catecholamine-induced changes in blood pressure of normotensive and spontaneously hypertensive rats

International Nuclear Information System (INIS)

Sankar, R.; Domer, F.R.; Taylor, B.

1982-01-01

Researchers have studied the effects of the pressor catecholamine, dopamine, and the depressor catecholamine, isoproterenol, on the systemic blood pressure and the permeability of the blood-brain barrier (BBB) to albumin in normotensive (WKY) and spontaneously hypertensive (SHR) rats. The rats were anesthetized with pentobarbital. The permeability of the BBB to protein was measured by the extravasation of radioiodinated serum albumin (RISA). The permeability was decreased by both catecholamines despite the dose-dependent, yet opposite, changes in blood pressure in the WKY rats. The blood pressure response to both of the catecholamines was enhanced in the SHR rats. Isoproterenol caused a decrease in the permeability of the BBB in the SHR but dopamine did not. Results with both WKY and SHR rats are suggestive of an adrenergically-mediated decrease in movement across the BBB of compounds of large molecular weight, regardless of changes in blood pressure

Tissue to plasma capillary permeability of 131I-albumin in the perfused rabbit ear

DEFF Research Database (Denmark)

Bent-Hansen, L; Svendsen, Jesper Hastrup

1991-01-01

The tissue to plasma transfer of 131I-albumin was recorded in perfused rabbit ears (n = 6) following equilibration for 24 hr. 125I-fibrinogen served as the plasma marker, and was introduced intravenously 15 min before clamping. The ears were rollerpump perfused with isotonic diluted plasma...

Modeling error and stability of endothelial cytoskeletal membrane parameters based on modeling transendothelial impedance as resistor and capacitor in series.

Science.gov (United States)

Bodmer, James E; English, Anthony; Brady, Megan; Blackwell, Ken; Haxhinasto, Kari; Fotedar, Sunaina; Borgman, Kurt; Bai, Er-Wei; Moy, Alan B

2005-09-01

Transendothelial impedance across an endothelial monolayer grown on a microelectrode has previously been modeled as a repeating pattern of disks in which the electrical circuit consists of a resistor and capacitor in series. Although this numerical model breaks down barrier function into measurements of cell-cell adhesion, cell-matrix adhesion, and membrane capacitance, such solution parameters can be inaccurate without understanding model stability and error. In this study, we have evaluated modeling stability and error by using a chi(2) evaluation and Levenberg-Marquardt nonlinear least-squares (LM-NLS) method of the real and/or imaginary data in which the experimental measurement is compared with the calculated measurement derived by the model. Modeling stability and error were dependent on current frequency and the type of experimental data modeled. Solution parameters of cell-matrix adhesion were most susceptible to modeling instability. Furthermore, the LM-NLS method displayed frequency-dependent instability of the solution parameters, regardless of whether the real or imaginary data were analyzed. However, the LM-NLS method identified stable and reproducible solution parameters between all types of experimental data when a defined frequency spectrum of the entire data set was selected on the basis of a criterion of minimizing error. The frequency bandwidth that produced stable solution parameters varied greatly among different data types. Thus a numerical model based on characterizing transendothelial impedance as a resistor and capacitor in series and as a repeating pattern of disks is not sufficient to characterize the entire frequency spectrum of experimental transendothelial impedance.

Urine Albumin and Albumin/ Creatinine Ratio

Science.gov (United States)

... it used? The urine albumin test or albumin/creatinine ratio (ACR) is used to screen people with chronic conditions, such as diabetes and high blood pressure ( hypertension ) that put them at an ...

Relation between histamine release and dye permeability of pulmonary blood-air barrier in x-irradiated rat

Energy Technology Data Exchange (ETDEWEB)

Yamazaki, H [Kobe Univ. (Japan). School of Medicine

1976-04-01

The histamine-release kinetics and the influence of released histamine on the permeability of the pulmonary blood-air(BA) barrier during the early period after either whole-body or thoracic x irradiation of the rat were studied. Histamine contents of skin and lung of the irradiated rat decreased rapidly, reaching a minimum at 5 h, and this histamine depletion continued for at least 7 days. Conversely, in circulating blood histamine increased during the early period of 5 h and then decreased gradually. This early increase was linear up to 500R and then became saturated between 500 and 1,000R. Administration of polymixine B (5mg/100g body weight) to rats liberated histamine similarly. Rat sera containg histamine released soon after irradiation enhanced the capillary permeability of Evans blue(EB) in the guinea pig skin reaction, which was effectively countered by pretreatment of the guinea pig with anti-histaminic pyribenzamine (29..mu..g/100g body weight), but not by anti-serotonic chlorpromazine (0.3mg/100g body weight). Similarly, perhaps only the EB-bound serum albumin (EB-albumin), that was seen in alveolar perfusate, penetrated more through the pulmonary BA-barrier with increasing x-ray dose, in parallel with the increase in blood histamine. Pyribenzamine inhibited this effect effectively, but cysteamine (a radical scavenger) did so only partially. Thus, it seems possible that at soon after x irradiation the enhanced permeability of EB-albumin through the BA barrier of rat lung is due preferentially to the pharmacologic action of released histamine and subsidiarily to radiation damage to pulmonary cells.

Airway mucosal permeability in chronic bronchitics and bronchial asthmatics with hypersecretion

International Nuclear Information System (INIS)

Honda, I.; Shimura, S.; Sasaki, T.; Sasaki, H.; Takishima, T.; Nakamura, M.

1988-01-01

To determine airway mucosal permeability, radiolabeled albumin in sputum was examined on the basis of a 2-h period of sputum collection for as long as 8h after intravenous administration of 131 I-labeled human serum albumin. This technique was applied to 12 patients with bronchial asthma associated with hypersecretion or chronic bronchitis. Group A consisted of 6 asthmatics (2 females and 4 males, 56.0 +/- 6.4 yr of age, mean +/- SEM); Group B consisted of 6 bronchitics (3 females and 3 males, 53.8 +/- 6.5 yr of age). Between Groups A and B, there was no significant difference in sputum volume per day or in obstructive impairment. Radiolabeled albumin concentration (cpm/ml) was obtained from radiocount of each sputum sample and then divided by serum concentration at the time of each sampling (2, 4, 6, and 8 h after administration). Group B showed large values compared with those in Group A. In Group A, the ratios were 2.0 +/- 0.8, 2.5 +/- 0.5, 2.2 +/- 0.2, and 1.5 +/- 0.4% (mean +/- SEM) at 2, 4, 6, and 8 h after the administration, respectively, whereas in Group B, the ratios were 3.0 +/- 0.6, 7.0 +/- 1.8, 7.2 +/- 1.8, and 7.4 +/- 2.4%, respectively. The differences between Groups A and B were statistically significant (two-way analysis of variance). These findings suggest that an increase in airway mucosal permeability is due to mucosal epithelial damage by chronic inflammation in bronchitics and not to the underlying abnormality of asthma

The effect of metabolic regulation on microvascular permeability to small and large molecules in short-term juvenile diabetics

DEFF Research Database (Denmark)

Parving, H H; Noer, Ivan; Deckert, Toke

1976-01-01

injected 125I-labelled human serum albumin; GFR was measured on the forearm by straingauge plethysmography and CDS for 51Cr-EDTA clearance; CFC was measured on the forearm by straingauge plethysmography and CDC, for 51Cr-EDTA was determined in the jyperaemic anterio tibial muscle by the local clearance......The microvascular permeability to small and large molecules was studied during good and poor metabolic regulation in ten short duration juvenile diabetics. The following variables were measured; daily urinary albumin and beta2-microglobulin-excretion rates, whole body transcapillary escape rate...... of albumin (TER), glomerular filtration rate (GFR), capillary filtration coefficient (CFC), and capillary diffusion capacity (CDC). The urinary albumin and beta2-microglobulin concentration were measured by sensitive radioimmunoassays; TER was detemined from the initial disappearance of intravenously...

Lab-on-a-brane: A novel physiologically relevant planar arterial model to study transendothelial transport

Science.gov (United States)

Budhwani, Karim Ismail

The tremendous quality of life impact notwithstanding, cardiovascular diseases and Cancer add up to over US$ 700bn each year in financial costs alone. Aging and population growth are expected to further expand the problem space while drug research and development remain expensive. However, preclinical costs can be substantially mitigated by substituting animal models with in vitro devices that accurately model human cardiovascular transport. Here we present a novel physiologically relevant lab-on-a-brane that simulates in vivo pressure, flow, strain, and shear waveforms associated with normal and pathological conditions in large and small blood vessels for studying molecular transport across the endothelial monolayer. The device builds upon previously demonstrated integrated microfluidic loop design by: (a) introducing nanoscale pores in the substrate membrane to enable transmembrane molecular transport, (b) transforming the substrate membrane into a nanofibrous matrix for 3D smooth muscle cell (SMC) tissue culture, (c) integrating electrospinning fabrication methods, (d) engineering an invertible sandwich cell culture device architecture, and (e) devising a healthy co-culture mechanism for human arterial endothelial cell (HAEC) monolayer and multiple layers of human smooth muscle cells (HSMC) to accurately mimic arterial anatomy. Structural and mechanical characterization was conducted using confocal microscopy, SEM, stress/strain analysis, and infrared spectroscopy. Transport was characterized using FITC-Dextran hydraulic permeability protocol. Structure and transport characterization successfully demonstrate device viability as a physiologically relevant arterial mimic for testing transendothelial transport. Thus, our lab-on-a-brane provides a highly effective and efficient, yet considerably inexpensive, physiologically relevant alternative for pharmacokinetic evaluation; possibly reducing animals used in pre-clinical testing, clinical trials cost from false

HIV-1 Tat reduces nephrin in human podocytes: a potential mechanism for enhanced glomerular permeability in HIV-associated nephropathy.

Science.gov (United States)

Doublier, Sophie; Zennaro, Cristina; Spatola, Tiziana; Lupia, Enrico; Bottelli, Antonella; Deregibus, Maria Chiara; Carraro, Michele; Conaldi, Pier Giulio; Camussi, Giovanni

2007-02-19

To determine whether HIV-1 Tat may directly alter glomerular permeability in HIV-associated nephropathy (HIVAN). Heavy proteinuria is a hallmark of HIVAN. The slit diaphragm is the ultimate glomerular filtration barrier critical for maintaining the efficiency of the ultrafiltration unit of the kidney. In this study, we evaluated the direct effect of Tat protein on the permeability of isolated glomeruli and on the expression of nephrin, the main slit diaphragm component, by human cultured podocytes. Permeability was studied by measuring the permeability to albumin in isolated rat glomeruli. We also evaluated the expression of nephrin in human cultured podocytes by using immunofluorescence and Western blot. We found that Tat increased albumin permeability in isolated glomeruli, and rapidly induced the redistribution and loss of nephrin in cultured podocytes. Pretreatment of glomeruli and podocytes with blocking antibodies showed that Tat reduced nephrin expression by engaging vascular endothelial growth factor receptors types 2 and 3 and the integrin alphavbeta3. Pre-incubation of podocytes with two platelet-activating factor (PAF) receptor antagonists prevented the loss and redistribution of nephrin induced by Tat, suggesting that PAF is an intracellular mediator of Tat action. Tat induced a rapid PAF synthesis by podocytes. When podocytes transfected to overexpress PAF-acetylhydrolase, the main catabolic enzyme of PAF, were stimulated with Tat, the redistribution and loss of nephrin was abrogated. The present results define a mechanism by which Tat may reduce nephrin expression in podocytes, thus increasing glomerular permeability. This provides new insights in the understanding of HIVAN pathogenesis.

Changes in cardiac output and incidence of volume overload in cirrhotics receiving 20% albumin infusion.

Science.gov (United States)

Shasthry, Saggere M; Kumar, Manoj; Khumuckham, Jelen S; Sarin, Shiv Kumar

2017-08-01

Patients with cirrhosis are prone to develop volume over load, have increased capillary permeability and latent or overt cardiomyopathy. Whether albumin infusion causes volume overload in cirrhotics has not been adequately studied. Ninety nine consecutive cirrhotic patients receiving 1gm per kg albumin infusion were evaluated for development of volume overload. Clinical, echocardiographic and haemodynamic changes were closely monitored during and after albumin infusion. Thirty (30.30%) patients developed volume overload. Patients with higher BMI (P=.003), lower CTP (P=.01) and MELD (P=.034) were more often associated with the development of volume overload. Though baseline diastolic dysfunction was present in 82.8% of the patients, it did not influence the development of volume overload or changes in the cardiac output. The cardiac output increased significantly after albumin infusion (4.9±1.554 L/min to 5.86±1.85 L/min, Palbumin infusion develop volume overload, specially, those with higher BMI and lower severity of liver disease. Cardiac output increases after albumin infusion, and, baseline diastolic dysfunction has little effect on the development of volume overload or changes in cardiac output. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Permeability of endothelial and astrocyte cocultures: in vitro blood-brain barrier models for drug delivery studies.

Science.gov (United States)

Li, Guanglei; Simon, Melissa J; Cancel, Limary M; Shi, Zhong-Dong; Ji, Xinying; Tarbell, John M; Morrison, Barclay; Fu, Bingmei M

2010-08-01

The blood-brain barrier (BBB) is a major obstacle for drug delivery to the brain. To seek for in vitro BBB models that are more accessible than animals for investigating drug transport across the BBB, we compared four in vitro cultured cell models: endothelial monoculture (bEnd3 cell line), coculture of bEnd3 and primary rat astrocytes (coculture), coculture with collagen type I and IV mixture, and coculture with Matrigel. The expression of the BBB tight junction proteins in these in vitro models was assessed using RT-PCR and immunofluorescence. We also quantified the hydraulic conductivity (L (p)), transendothelial electrical resistance (TER) and diffusive solute permeability (P) of these models to three solutes: TAMRA, Dextran 10K and Dextran 70K. Our results show that L (p) and P of the endothelial monoculture and coculture models are not different from each other. Compared with in vivo permeability data from rat pial microvessels, P of the endothelial monoculture and coculture models are not significantly different from in vivo data for Dextran 70K, but they are 2-4 times higher for TAMRA and Dextran 10K. This suggests that the endothelial monoculture and all of the coculture models are fairly good models for studying the transport of relatively large solutes across the BBB.

Aortic lipid and 125I-albumin accumulation in streptozotocin-diabetic guinea pigs: prevention by insulin treatment

International Nuclear Information System (INIS)

Schlosser, M.J.; Bannon, A.W.; Verlangieri, A.J.

1986-01-01

Diabetes mellitus, a major risk factor of atherosclerosis, is associated with the aortic accumulation of macromolecules. The authors have examined this relationship in the streptozotocin (STZ)-diabetic guinea pig, a species (like man) unable to synthesize ascorbic acid and susceptible to atherosclerosis. Male Dunkin-Hartley guinea pigs received STZ (150 mg/kg, i.c.) or vehicle (control). After 5 days, insulin (10 U/kg/day) was given to half the STZ animals (STZ-INS0 while the remaining half (STZ-SAL) and controls received saline. 25 days later, animals were given 125 I-albumin (100 μCi/kg, i.a.). Activity was determined in plasma at 5 (C/sub p5), 15 and 30 minutes, and in the upper thoracic aorta after 30 minutes. Histopathological changes were evaluated in the lower aorta. Aortic albumin permeability defined as cpm/cm 2 /sec, cpm/cm 2 /sec/C/sub p5/, or cpm/C/sub p5//g tissue was significantly elevated in the STZ-SAL group compared to both STZ-INS and control groups; these latter two groups were not significantly different from each other. Oil-Red-O positive material (lipid) occurred at multifocal areas within the intima of the STZ-SAL animals only. This study demonstrates (1) an abnormal increase in aortic permeability to albumin, (2) histological evidence of early atherosclerotic lesions, and (3) that insulin treatment can prevent these angiopathies in this STZ-diabetic animal model

Albumin and multiple sclerosis.

Science.gov (United States)

LeVine, Steven M

2016-04-12

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.

Albumin receptor effect may be due to a surface-induced conformational change in albumin

International Nuclear Information System (INIS)

Reed, R.G.; Burrington, C.M.

1989-01-01

To determine whether equilibrium binding between albumin and hepatocytes involves a cell surface receptor for albumin, we incubated freshly isolated rat hepatocytes with 125 I-albumin and determined the amount of albumin associated with the cells as a function of the total albumin concentration. The resulting two-phase binding curve showed the rat albumin-hepatocyte interaction to consist of a saturable binding interaction with a dissociation constant of 1.1 microM and 2 X 10(6) sites/cell in addition to a weak, nonsaturable binding interaction. However, the saturable binding of albumin to hepatocytes did not appear to result from the presence of an albumin receptor on the cell surface; the interaction was the same for different species of albumin, for chemically modified albumins, and for fragments of albumin representing mutually exclusive domains of the molecule. The saturable binding was, instead, found to involve a subpopulation of albumin with an enhanced affinity for the cell surface. We show that this subpopulation of albumin is generated upon contact with either solid surfaces or cell surfaces and can be transferred from one surface to another. We propose that the two-phase Scatchard binding curve and the ''albumin receptor effect'' reflect two populations of albumin that bind to the cell surface with different affinities rather than one population of albumin that binds to two classes of binding sites

Profile of total protein, albumin, globulin and albumin globulin ratio in bulls

Directory of Open Access Journals (Sweden)

Ida Zahidah Irfan

2014-06-01

Full Text Available Determination of serum total protein concentration and main fractions (albumin and globulin can be used as an important diagnostic tool in clinical biochemistry. Several factors can affect the concentration of total protein, albumin, globulin and albumin globulin ratio (A/G. The aim of this study is to obtain serum protein profiles, albumin, globulin and A/G ratio based on breed, age and BCS (body condition score. Blood samples from 160 bulls were collected. Blood chemistry were analyzed by photometer principle using a commercial kit. There were significant (P<0.001 breed variation on total protein, albumin, globulin and albumin globulin ratio. Significant age differences were observed on total protein and albumin concentration (P<0.001, while globulin concentration and A/G ratio were also significant (P<0.05. Amongs groups of BCS, significant difference was verified only in the albumin concentration (P<0.05. The concentration of total proteins, albumins and globulins in the serum of the bulls are higher than standard values for cattle, while A/G ratio is lower.

Transcytosis Involvement in Transport System and Endothelial Permeability of Vascular Leakage during Dengue Virus Infection

Directory of Open Access Journals (Sweden)

Chanettee Chanthick

2018-02-01

Full Text Available The major role of endothelial cells is to maintain homeostasis of vascular permeability and to preserve the integrity of vascular vessels to prevent fluid leakage. Properly functioning endothelial cells promote physiological balance and stability for blood circulation and fluid components. A monolayer of endothelial cells has the ability to regulate paracellular and transcellular pathways for transport proteins, solutes, and fluid. In addition to the paracellular pathway, the transcellular pathway is another route of endothelial permeability that mediates vascular permeability under physiologic conditions. The transcellular pathway was found to be associated with an assortment of disease pathogeneses. The clinical manifestation of severe dengue infection in humans is vascular leakage and hemorrhagic diatheses. This review explores and describes the transcellular pathway, which is an alternate route of vascular permeability during dengue infection that corresponds with the pathologic finding of intact tight junction. This pathway may be the route of albumin transport that causes endothelial dysfunction during dengue virus infection.

Identification of two immortalized cell lines, ECV304 and bEnd3, for in vitro permeability studies of blood-brain barrier.

Directory of Open Access Journals (Sweden)

Shu Yang

Full Text Available To identify suitable cell lines for a mimetic system of in vivo blood-brain barrier (BBB for drug permeability assessment, we characterized two immortalized cell lines, ECV304 and bEnd3 in the respect of the tightness, tight junction proteins, P-glycoprotein (P-gp function and discriminative brain penetration. The ECV304 monoculture achieved higher transendothelial electrical resistance (TEER and lower permeability to Lucifer yellow than bEnd3. However, co-culture with rat glioma C6 cells impaired the integrity of ECV304 and bEnd3 cell layers perhaps due to the heterogeneity among C6 cells in inducing BBB characteristics. The immunostaining of ZO-1 delivered distinct bands along cell borders on both cell lines while those of occludin and claudin-5 were diffused and weak. P-gp functionality was only proved in bEnd3 by Rhodamine 123 (R123 uptake assay. A permeability test of reference compounds displayed a similar rank order (digoxin < R123 < quinidine, verapamil < propranolol in ECV304 and bEnd3 cells. In comparison with bEnd3, ECV304 developed tighter barrier for the passage of reference compounds and higher discrimination between transcellular and paracellular transport. However, the monoculture models of ECV304 and bEnd3 fail to achieve the sufficient tightness of in vitro BBB permeability models with high TEER and evident immunostaining of tight junction proteins. Further strategies to enhance the paracellular tightness of both cell lines to mimic in vivo BBB tight barrier deserve to be conducted.

Normal overall leakiness of microvasculature for albumin in patients with chronic obstructive lung disease (COLD).

Science.gov (United States)

Henriksen, J H; Kok-Jensen, A

1984-04-01

The overall extravasation rate of albumin, TER (i.e. the fraction of the intravascular albumin mass (IVM) passing into, and during steady state returning from, the extravascular space per unit time) was determined from the disappearance of i.v. injected radioiodinated serum albumin in seven patients with severe chronic obstructive lung disease (COLD) and in seven normal controls. Arterial oxygen tension in patients with COLD was median 60 mmHg (range 47-80, normal greater than 75 mmHg), vital capacity was on the average 55% of expected normal value (median 1.80 litre, range 1.45-1.95), and forced expired volume in first sec was decreased to 21% of expected normal value (median 0.55 litre, range 0.40-0.70). Right-heart catheterization revealed pulmonary hypertension in all but one patient. TER in patients with COLD was median 6.1% IVM/h (range 3.5-10.1) as compared to that of normal controls 6.0% IVM/h (range 4.3-7.4), indicating that no significant change in microvascular leakiness to albumin could be found in patients with COLD. Thus, the results bring no support to a generally increased microvascular permeability to proteins in patients with COLD.

Gamma scintigraphic analysis of albumin flux in patients with acute respiratory distress syndrome

International Nuclear Information System (INIS)

Sugerman, H.J.; Tatum, J.L.; Burke, T.S.; Strash, A.M.; Glauser, F.L.

1984-01-01

Computerized gamma-scintigraphy provides a new method for the analysis of albumin flux in patients with pulmonary permeability edema. In this technique, 10 mCi of 99 mTc -tagged human serum albumin is administered and lung:heart radioactivity ratios are determined. This ratio remains constant unless there is a leak of albumin, when a rising ratio with time, called the ''slope index'' (SI), is seen. Thirty-five scintigraphic studies were obtained in 28 patients by means of a portable computerized gamma-camera. Thirteen of these patients had clinical evidence of the acute respiratory distress syndrome (ARDS) and six had or were recovering from left ventricular induced congestive heart failure (CHF). Five of the patients with CHF and pulmonary capillary wedge pressure (PCWP) below 30 mm Hg had normal scintigraphic studies. The patients with ARDS were found to have significantly higher SIs than patients who did not have, or had recovered from, ARDS. Positive SIs were present from 1 to 8 days following the apparent onset of ARDS in seven studies in five patients. Recovery of gas exchange was associated with a return to a normal SI in four patients. In conclusion, computerized gamma-scintigraphy was a sensitive, noninvasive tool for the detection of a pathologic increase in pulmonary protein flux. Positive scintigraphic findings were associated with significantly impaired gas exchange. The method documented that the leak of albumin in patients with ARDS may last for days but resolves with recovery

Direct comparison of two albumin-based paclitaxel-loaded nanoparticle formulations: is the crosslinked version more advantageous?

Science.gov (United States)

Li, Chunlei; Li, Yanhui; Gao, Yuqing; Wei, Na; Zhao, Xi; Wang, Caixia; Li, Yongfeng; Xiu, Xian; Cui, Jingxia

2014-07-01

Nanoparticles using albumin as particle matrix have entered the mainstream of drug delivery. It was reported that non-crosslinked albumin nanoparticles were unstable in circulation and could deliver drugs into tumor through gp60/SPARC pathway; in contrast, the delivery of drugs with stable nanoparticles was dependent on enhanced permeability and retention effect. Thus, it is questionable which kind of nanoparticles was more advantageous. Two versions of albumin-bound paclitaxel nanoparticles were prepared. In vitro, the non-crosslinked particles could rapidly disintegrate and the crosslinked was stable. The pharmacokinetics of both formulations was different especially at early time and the non-crosslinked particles were cleared rapidly. After non-crosslinked particle treatment paclitaxel had a tendency to accumulate into heart and kidney and following therapy with the crosslinked particles, paclitaxel was liable to be delivered into lung, spleen and liver. The delivery efficiency of paclitaxel into tumor following the non-crosslinked particle treatment was greater than that of the crosslinked (palbumin nanoparticles. Copyright © 2014 Elsevier B.V. All rights reserved.

Enhancing Docetaxel Delivery to Multidrug-Resistant Cancer Cells with Albumin-Coated Nanocrystals.

Science.gov (United States)

Gad, Sheryhan F; Park, Joonyoung; Park, Ji Eun; Fetih, Gihan N; Tous, Sozan S; Lee, Wooin; Yeo, Yoon

2018-01-29

Intravenous delivery of poorly water-soluble anticancer drugs such as docetaxel (DTX) is challenging due to the low bioavailability and the toxicity related to solubilizing excipients. Colloidal nanoparticles are used as alternative carriers, but low drug loading capacity and circulation instability limit their clinical translation. To address these challenges, DTX nanocrystals (NCs) were prepared using Pluronic F127 as an intermediate stabilizer and albumin as a functional surface modifier, which were previously found to be effective in producing small and stable NCs. We hypothesize that the albumin-coated DTX NCs (DTX-F-alb) will remain stable in serum-containing medium so as to effectively leverage the enhanced permeability and retention effect. In addition, the surface-bound albumin, in its native form, may contribute to cellular transport of NCs through interactions with albumin-binding proteins such as secreted protein acidic and rich in cysteine (SPARC). DTX-F-alb NCs showed sheet-like structure with an average length, width, and thickness of 284 ± 96, 173 ± 56, and 40 ± 8 nm and remained stable in 50% serum solution at a concentration greater than 10 μg/mL. Cytotoxicity and cellular uptake of DTX-F-alb and unformulated (free) DTX were compared on three cell lines with different levels of SPARC expression and DTX sensitivity. While the uptake of free DTX was highly dependent on DTX sensitivity, DTX-F-alb treatment resulted in relatively consistent cellular levels of DTX. Free DTX was more efficient in entering drug-sensitive B16F10 and SKOV-3 cells than DTX-F-alb, with consistent cytotoxic effects. In contrast, multidrug-resistant NCI/ADR-RES cells took up DTX-F-alb more than free DTX with time and responded better to the former. This difference was reduced by SPARC knockdown. The high SPARC expression level of NCI/ADR-RES cells, the known affinity of albumin for SPARC, and the opposing effect of SPARC knockdown support that DTX-F-alb have exploited the

Effects of hypothyroidism on vascular 125I-albumin permeation and blood flow in rats

International Nuclear Information System (INIS)

Tilton, R.G.; Pugliese, G.; Chang, K.; Speedy, A.; Province, M.A.; Kilo, C.; Williamson, J.R.

1989-01-01

Effects of hypothyroidism on vascular 125I-albumin permeation and on blood flow were assessed in multiple tissues of male Sprague-Dawley rats rendered hypothyroid by dietary supplementation with 0.5% (wt/wt) 2-thiouracil or by thyroidectomy. In both thiouracil-treated and thyroidectomized rats, body weights, kidney weight, arterial blood pressure, and pulse rate were decreased significantly v age-matched controls. After 10 to 12 weeks of thiouracil treatment, 125I-albumin permeation was increased significantly in the kidney, aorta, eye (anterior uvea, choroid, retina), skin, and new granulation tissue, remained unchanged in brain, sciatic nerve, and heart, and was decreased in forelimb skeletal muscle. A similar pattern was observed in thyroidectomized rats, except that increases in 125I-albumin permeation for all tissues were smaller than those observed in thiouracil-treated rats, and 125I-albumin permeation in retina did not differ from controls. In both thiouracil-treated and thyroidectomized rats, changes in blood flow (assessed with 15-microns, 85Sr-labeled microspheres) relative to the decrease in arterial blood pressure were indicative of a decrease in regional vascular resistance except in the choroid and in the kidney, in which vascular resistance was increased significantly. Glomerular filtration rate was decreased, but filtration fraction and urinary excretion of albumin remained unchanged by thiouracil treatment and thyroidectomy. These results indicate that vascular hemodynamics and endothelial cell barrier functional integrity are modulated in many different tissues by the thyroid. In view of the correspondence of hypothyroid- and diabetes-induced vascular permeability changes, these results raise the possibility that altered thyroid function in diabetes may play a role in the pathogenesis of diabetic vascular disease

Transendothelial exchange of low-density lipoprotein is unaffected by the presence of severe atherosclerosis

DEFF Research Database (Denmark)

Kornerup, Karen; Nordestgaard, Børge Grønne; Jensen, Trine Krogsgaard

2004-01-01

intravenously (i.v.), and the 1-h fractional escape rates (FER(LDL) and FER(alb)) were taken as indices of transendothelial exchange. RESULTS: Patients with coronary or peripheral atherosclerosis had FER(LDL) similar to that of controls [4.3 (3.5-5.1) and 3.2 (2.3-4.1) versus 4.2 (3.7-4.7)%/h; P>0.05], even...... after adjustment for LDL distribution volume (DV(LDL)). In contrast, diabetes patients had significantly higher FER(LDL) than controls [5.2 (4.6-5.7) versus 4.2 (3.7-4.7)%/h; P..., FER(alb) was not elevated in patients with coronary atherosclerosis, possibly elevated in patients with peripheral atherosclerosis, but was elevated in diabetes patients. There was a tight positive correlation between FER(LDL) and FER(alb) in all groups of patients and controls. CONCLUSION...

Plasma proteins in a standardised skin mini-erosion (I: permeability changes as a function of time

Directory of Open Access Journals (Sweden)

Ryan Terence J

2002-02-01

Full Text Available Abstract Background A standardised technique using a suction-induced mini-erosion that allows serial sampling of dermal interstitial fluid (IF for 5 to 6 days has been described. In the present study, we studied permeability changes as a function of time. Methods We examined IF concentrations of total protein concentration and the concentration of insulin (6.6 kDa, prealbumin (55 kDa, albumin (66 kDa, transferrin (80 kDa, IgG (150 kDa and alpha-2-macroglobulin (720 kDa as a function of time, using an extraction pressure of 200 mmHg below atmospheric. Results At 0 h after forming the erosion, mean total IF protein content (relative to plasma was 26 ± 13% (SD. For the individual proteins, the relative mean concentrations were 65 ± 36% for insulin, 48 ± 12% for albumin, 30 ± 19% for transferrin, 31 ± 15%for IgG and 19.5 ± 10% for alpha-2-macroglobulin. At 24 h, the total IF protein content was higher than at 0 h (56 ± 26% vs 26 ± 13%; p Conclusions The results indicate that fluid sampled at 0 h after forming the erosion represents dermal IF before the full onset of inflammation. From 24 h onward, the sampled fluid reflects a steady state of increased permeability induced by inflammation. This technique is promising as a tool for clinically sampling substances that are freely distributed in the body and as a model for studying inflammation and vascular permeability.

An in vitro transport model for rapid screening and predicting the permeability of candidate compounds at blood-brain barrier.

Science.gov (United States)

Yang, Zhi-Hong; Sun, Xiao; Mei, Chao; Sun, Xiao-Bo; Liu, Xiao-Dong; Chang, Qi

2011-12-01

The aim of this study was to design and develop a simple in vitro blood-brain barrier (BBB) permeation model for elementarily and rapidly predicting the permeability of candidate compounds at BBB and further evaluating whether P-glycoprotein (P-gp) affects them across BBB. The model was mainly composed of cultured rat brain microvascular endothelial cells (rBMECs), glass contraption, and micropore membrane. First, we evaluated the model by morphological observation. Second, the restriction effects of paracellular transport were verified by measuring marker probes transport, and monitoring transendothelial electrical resistance (TEER) and leakage. Finally, protein expression and activity of P-gp were confirmed by carrying out Western blot analysis and polarized transport of rhodamine-123 (Rho123) in rBMECs. The rBMECs retained both endothelial cells and BBB features. The rBMECs model reproducibly attained approximately 130 Ω cm² on the steady-state TEER value, and displayed a barrier function to marker probes transport by decreasing the permeability. Protein band of 170 kDa manifested the existence of P-gp in the rBMECs, and the findings of cyclosporin A-sensitive decrease of Rho123 efflux confirmed the presence of P-gp activity. A simple, rapid, and convenient in vitro BBB permeation model was successfully established and applied to evaluate the BBB transport profiles of three natural flavonoids: quercetin, naringenin, and rutin.

Radioimmunoassay for urinary albumin

International Nuclear Information System (INIS)

Woo, J.; Floyd, M.; Cannon, D.C.; Kahan, B.

1978-01-01

We describe a rapid, sensitive, and precise radioimmunoassay for urinary albumin (U/sub alb/). Aliquots of diluted urine were incubated at room temperature for 1 h with 125 I-labelled albumin and a rabbit antiserum monospecifid for human albumin. Phase separation was effected by the double-antibody technique. The dose-response curve was linear in the range of 15.6 to 10,000 ng, equivalent to 4 to 3000 mg/liter of urine. The limit of sensitivity was 16 ng of albumin. The coefficient of assay variation was 4.8%, both at 44 mg/liter and at 1304 mg/liter. A displacement curve obtained with a serially diluted urine sample of high albumin concentration was completely superimposable with the curve for which human albumin was used as a standard. In 26 normal individuals the range for U/sub alb/ was 2.2 to 12.6 mg/24 h, and for albumin clearance (C/sub alb/), 1.8 x 10 -5 --19.6 x 10 -5 ml/min. After renal homografts in 25 patients, U/sub alb/ ranged from 16.9 to 9928 mg/24 h, and C/sub alb/ from 2.7 x 10 -4 to 1.7 x 10 -1 ml/min. Both increased U/sub alb/ and C/sub alb/ correlated well with the severity of renal homograft rejection

Effects of hypothyroidism on vascular /sup 125/I-albumin permeation and blood flow in rats

Energy Technology Data Exchange (ETDEWEB)

Tilton, R.G.; Pugliese, G.; Chang, K.; Speedy, A.; Province, M.A.; Kilo, C.; Williamson, J.R.

1989-05-01

Effects of hypothyroidism on vascular 125I-albumin permeation and on blood flow were assessed in multiple tissues of male Sprague-Dawley rats rendered hypothyroid by dietary supplementation with 0.5% (wt/wt) 2-thiouracil or by thyroidectomy. In both thiouracil-treated and thyroidectomized rats, body weights, kidney weight, arterial blood pressure, and pulse rate were decreased significantly v age-matched controls. After 10 to 12 weeks of thiouracil treatment, 125I-albumin permeation was increased significantly in the kidney, aorta, eye (anterior uvea, choroid, retina), skin, and new granulation tissue, remained unchanged in brain, sciatic nerve, and heart, and was decreased in forelimb skeletal muscle. A similar pattern was observed in thyroidectomized rats, except that increases in 125I-albumin permeation for all tissues were smaller than those observed in thiouracil-treated rats, and 125I-albumin permeation in retina did not differ from controls. In both thiouracil-treated and thyroidectomized rats, changes in blood flow (assessed with 15-microns, 85Sr-labeled microspheres) relative to the decrease in arterial blood pressure were indicative of a decrease in regional vascular resistance except in the choroid and in the kidney, in which vascular resistance was increased significantly. Glomerular filtration rate was decreased, but filtration fraction and urinary excretion of albumin remained unchanged by thiouracil treatment and thyroidectomy. These results indicate that vascular hemodynamics and endothelial cell barrier functional integrity are modulated in many different tissues by the thyroid. In view of the correspondence of hypothyroid- and diabetes-induced vascular permeability changes, these results raise the possibility that altered thyroid function in diabetes may play a role in the pathogenesis of diabetic vascular disease.

Expression of PKA inhibitor (PKI) gene abolishes cAMP-mediated protection to endothelial barrier dysfunction.

Science.gov (United States)

Lum, H; Jaffe, H A; Schulz, I T; Masood, A; RayChaudhury, A; Green, R D

1999-09-01

We investigated the hypothesis that cAMP-dependent protein kinase (PKA) protects against endothelial barrier dysfunction in response to proinflammatory mediators. An E1-, E3-, replication-deficient adenovirus (Ad) vector was constructed containing the complete sequence of PKA inhibitor (PKI) gene (AdPKI). Infection of human microvascular endothelial cells (HMEC) with AdPKI resulted in overexpression of PKI. Treatment with 0.5 microM thrombin increased transendothelial albumin clearance rate (0.012 +/- 0.003 and 0.035 +/- 0.005 microl/min for control and thrombin, respectively); the increase was prevented with forskolin + 3-isobutyl-1-methylxanthine (F + I) treatment. Overexpression of PKI resulted in abrogation of the F + I-induced inhibition of the permeability increase. However, with HMEC infected with ultraviolet-inactivated AdPKI, the F + I-induced inhibition was present. Also, F + I treatment of HMEC transfected with reporter plasmid containing the cAMP response element-directed transcription of the luciferase gene resulted in an almost threefold increase in luciferase activity. Overexpression of PKI inhibited this induction of luciferase activity. The results show that Ad-mediated overexpression of PKI in endothelial cells abrogated the cAMP-mediated protection against increased endothelial permeability, providing direct evidence that cAMP-dependent protein kinase promotes endothelial barrier function.

Assessment of vascularity and permeability in brain tumor using SPECT and [sup 99m]Tc-DTPA-human serum albumin in relation to [sup 201]Tl SPECT

Energy Technology Data Exchange (ETDEWEB)

Nakagawara, Jyoji; Fukuoka, Seiji; Takahashi, Shuhei; Takahashi, Masaaki; Satoh, Katsuyasu; Suematsu, Katsumi; Nakamura, Jun-ichi (Nakamura Memorial Hospital, Sapporo (Japan))

1994-02-01

Single photon emission computed tomography (SPECT) using technetium-99m-DTPA-human serum albumin ([sup 99m]Tc-HSA-D) and thallium-201 chloride ([sup 201]Tl) was simultaneously performed on 25 patients with brain tumors; 10 with brain metastasis, 8 with astrocytoma (Gr. 3) and 7 with meningioma. The early image was obtained 10 minutes after [sup 99m]Tc-HSA-D (740 MBq) injection, and the delayed image was taken 5 hours after the injection. HSA-D index, based on the ratio of [sup 99m]Tc-HSA-D uptake in the tumor versus the cortical area, was calculated on each image, and compared with Tl index (tumor/contralateral cerebrum ratio). HSA-D delayed index was significantly greater than HSA-D early index in all tumor types (p<0.05 by the Wilcoxon ranked sign test). Linear correlation between HSA-D early index and HSA-D delayed index was significant in astrocytoma (GR. 3) (p<0.01) and meningioma (p<0.001), and a linear correlation between HSA-D delayed index and Tl index was significant in astrocytoma (Gr. 3) (p<0.05). It is concluded that HSA-D early index and delayed index could reflect tumor vascularity and permeability, respectively, and provide supplementary information for Tl index. (author).

Urinary albumin in space missions

DEFF Research Database (Denmark)

Cirillo, Massimo; De Santo, Natale G; Heer, Martina

2002-01-01

Proteinuria was hypothesized for space mission but research data are missing. Urinary albumin, as index of proteinuria, was analyzed in frozen urine samples collected by astronauts during space missions onboard MIR station and on ground (control). Urinary albumin was measured by a double antibody...... radioimmunoassay. On average, 24h urinary albumin was 27.4% lower in space than on ground; the difference was statistically significant. Low urinary albumin excretion could be another effect of exposure to weightlessness (microgravity)....

Effect of leukotriene receptor antagonists on vascular permeability during endotoxic shock

International Nuclear Information System (INIS)

Cook, J.A.; Li, E.J.; Spicer, K.M.; Wise, W.C.; Halushka, P.V.

1990-01-01

Evidence has accumulated that sulfidopeptide leukotrienes are significant pathogenic mediators of certain hematologic and hemodynamic sequelae of endotoxic shock. In the present study, the effects of a selective LTD4/E4 receptor antagonist, LY171883 (LY), or a selective LTD4 receptor antagonist, SKF-104353 (SKF), were assessed on splanchnic and pulmonary localization of 99mTechnetium-labeled human serum albumin (99mTc-HSA) in acute endotoxic shock in the rat. Dynamic gamma camera imaging of heart (H), midabdominal (GI), and lung regions of interest generated time activity curves for baseline and at 5-35 min after Salmonella enteritidis endotoxin (10 mg/kg, i.v.). Slopes of GI/H and lung/H activity (permeability index, GI/H or lung/H X 10(-3)/min) provided indices of intestinal and lung localization. Rats received LY (30 mg/kg, i.v.), LY vehicle (LY Veh), SKF (10 mg/kg), or SKF vehicle (SK Veh) 10 min prior to endotoxin or endotoxin vehicle. In rats receiving the LY Veh and endotoxin (n = 8) or SKF Veh and endotoxin (n = 12), the splanchnic permeability indices to 99mTc-HSA were increased 11.2-fold and 5.1-fold, respectively (P less than 0.05) compared to vehicle control groups not given endotoxin (n = 5). Pulmonary permeability index for 99mTc-HSA was increased (P less than 0.05) to a lesser extent (3.2-fold) by endotoxin compared to vehicle controls. Pretreatment with SKF reduced the mesenteric permeability index to control levels (P less than 0.05) during the 5-35 min time interval post-endotoxin. LY reduced the mesenteric permeability index by 70%. Pulmonary relative permeability to 99mTc-HSA was not affected by LY pretreatment. Both splanchnic and lung relative permeability to the isotope was transient; at 135-225 min post-endotoxin, splanchnic localization of 99mTc-HSA (n = 4) was not significantly different from vehicle controls in these vascular beds

Albumin and pre-albumin levels do not reflect the nutritional status of female adolescents with restrictive eating disorders.

Science.gov (United States)

Huysentruyt, Koen; De Schepper, Jean; Vanbesien, Jesse; Vandenplas, Yvan

2016-04-01

Albumin and pre-albumin are frequently used as nutritional markers in clinical practice. We examined whether serum albumin and pre-albumin were predicted by body mass index (BMI), hydration and/or inflammation in female adolescents with a recently diagnosed restrictive eating disorder (RED). This was a retrospective study of female adolescents with RED from 2002 to 2011. Low albumin and pre-albumin levels were defined as nutritional status in adolescents with RED. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Albumin and its application in drug delivery.

Science.gov (United States)

Sleep, Darrell

2015-05-01

Rapid clearance of drugs from the body results in short therapeutic half-life and is an integral property of many protein and peptide-based drugs. To maintain the desired therapeutic effect patients are required to administer higher doses more frequently, which is inconvenient and risks undesirable side effects. Drug delivery technologies aim to minimise the number of administrations and dose-related toxicity while maximising therapeutic efficacy. This review describes albumin's inherent biochemical and biophysical properties, which make it an attractive drug delivery platform and the developmental status of drugs that are associated, conjugated or genetically fused with albumin. Albumin interacts with a number of cell surface receptors including gp18, gp30, gp60, FcRn, cubilin and megalin. The importance of albumin's interaction with the FcRn receptor, the basis for albumin's long circulatory half-life, is described, as are engineered albumins with improved pharmacokinetics. Albumin naturally accumulates at tumours and sites of inflammation, a characteristic which can be augmented by the addition of targeting ligands. The development of albumin drug conjugates which reply upon this property is described. Albumin's inherent biochemical and biophysical properties make it an ideal drug delivery platform. Recent advances in our understanding of albumin physiology and the improvement in albumin-based therapies strongly suggest that albumin-based therapies have a significant advantage over alternative technologies in terms of half-life, stability, versatility, safety and ease of manufacture. Given the importance of the albumin:FcRn interaction, the interpretation of the pharmacokinetic and pharmacodynamic profiles of albumin-based therapeutics with disturbed albumin:FcRn interaction may have to be reassessed. The FcRn receptor has additional functionality, especially in relation to immunology, antigen presentation and delivery of proteins across mucosal membranes

The impact of change in albumin assay on reference intervals, prevalence of 'hypoalbuminaemia' and albumin prescriptions.

Science.gov (United States)

Coley-Grant, Deon; Herbert, Mike; Cornes, Michael P; Barlow, Ian M; Ford, Clare; Gama, Rousseau

2016-01-01

We studied the impact on reference intervals, classification of patients with hypoalbuminaemia and albumin infusion prescriptions on changing from a bromocresol green (BCG) to a bromocresol purple (BCP) serum albumin assay. Passing-Bablok regression analysis and Bland-Altman plot were used to compare Abbott BCP and Roche BCG methods. Linear regression analysis was used to compare in-house and an external laboratory Abbott BCP serum albumin results. Reference intervals for Abbott BCP serum albumin were derived in two different laboratories using pathology data from adult patients in primary care. Prescriptions for 20% albumin infusions were compared one year before and one year after changing the albumin method. Abbott BCP assay had a negative bias of approximately 6 g/L compared with Roche BCG method.There was good agreement (y = 1.04 x - 1.03; R(2 )= 0.9933) between in-house and external laboratory Abbott BCP results. Reference intervals for the serum albumin Abbott BCP assay were 31-45 g/L, different to those recommended by Pathology Harmony and the manufacturers (35-50 g/L). Following the change in method there was a large increase in the number of patients classified as hypoalbuminaemic using Pathology Harmony references intervals (32%) but not when retrospectively compared to locally derived reference intervals (16%) compared with the previous year (12%). The method change was associated with a 44.6% increase in albumin prescriptions. This equated to an annual increase in expenditure of £35,234. We suggest that serum albumin reference intervals be method specific to prevent misclassification of albumin status in patients. Change in albumin methodology may have significant impact on hospital resources. © The Author(s) 2015.

21 CFR 862.1035 - Albumin test system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Albumin test system. 862.1035 Section 862.1035....1035 Albumin test system. (a) Identification. An albumin test system is a device intended to measure the albumin concentration in serum and plasma. Albumin measurements are used in the diagnosis and...

Presence of albumin mRNA precursors in nuclei of analbuminemic rat liver lacking cytoplasmic albumin mRNA.

OpenAIRE

Esumi, H; Takahashi, Y; Sekiya, T; Sato, S; Nagase, S; Sugimura, T

1982-01-01

Analbuminemic rats, which lack serum albumin, were previously found to have no albumin mRNA in the cytoplasm of the liver. In the present study, the existence of nuclear albumin mRNA precursors in the liver of analbuminemic rats was examined by RNA X cDNA hybridization kinetics. Albumin mRNA precursors were present in the nuclei of analbuminemic rat liver at almost normal levels, despite the absence of albumin mRNA from the cytoplasm. Nuclear RNA of analbuminemic rat liver was subjected to el...

Recombinant albumin monolayers on latex particles.

Science.gov (United States)

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.

Serum albumin: accuracy and clinical use.

Science.gov (United States)

Infusino, Ilenia; Panteghini, Mauro

2013-04-18

Albumin is the major plasma protein and its determination is used for the prognostic assessment of several diseases. Clinical guidelines call for monitoring of serum albumin with specific target cut-offs that are independent of the assay used. This requires accurate and equivalent results among different commercially available methods (i.e., result standardization) through a consistent definition and application of a reference measurement system. This should be associated with the definition of measurement uncertainty goals based on medical relevance of serum albumin to make results reliable for patient management. In this paper, we show that, in the current situation, if one applies analytical goals for serum albumin measurement derived from its biologic variation, the uncertainty budget derived from each step of the albumin traceability chain is probably too high to fulfil established quality levels for albumin measurement and to guarantee the accuracy needed for clinical usefulness of the test. The situation is further worsened if non-specific colorimetric methods are used for albumin measurement as they represent an additional random source of uncertainty. Copyright © 2013 Elsevier B.V. All rights reserved.

Albumin for End-Stage Liver Disease

Science.gov (United States)

2012-01-01

Albumin has been widely used in patients with cirrhosis in an attempt to improve circulatory and renal functions. The benefits of albumin infusions in preventing the deterioration in renal function associated with large-volume paracentesis, spontaneous bacterial peritonitis, and established hepatorenal syndrome in conjunction with a vasoconstrictor are well established. While some of these indications are supported by the results of randomized studies, others are based only on clinical experience and have not been proved in prospective studies. The paucity of well-designed trials, the high cost of albumin, the lack of a clear-cut survival benefit, and fear of transmitting unknown infections make the use of albumin controversial. The recent development of the molecular adsorbent recirculating system, an albumin dialysis, is an example of the capacity of albumin to act by mechanisms other than its oncotic effect. Efforts should be made to define the indications for albumin use, the dose required, and predictors of response, so that patients gain the maximum benefit from its administration. PMID:22403494

Detecting microalbuminuria by urinary albumin/creatinine concentration ratio

DEFF Research Database (Denmark)

Jensen, J S; Clausen, P; Borch-Johnsen, K

1997-01-01

BACKGROUND: Microalbuminuria, i.e. a subclinical increase of the albumin excretion rate in urine, may be a novel atherosclerotic risk factor. This study aimed to test whether microalbuminuria can be identified by measurement of urinary albumin concentration or urinary albumin/creatinine concentra......BACKGROUND: Microalbuminuria, i.e. a subclinical increase of the albumin excretion rate in urine, may be a novel atherosclerotic risk factor. This study aimed to test whether microalbuminuria can be identified by measurement of urinary albumin concentration or urinary albumin/creatinine...... not included. Urinary albumin (Ualb) and creatinine (Ucreat) concentrations were measured in an overnight collected sample by enzyme-linked immunosorbent and colorimetric assays, respectively. Urinary albumin excretion rate (UAER) and urinary albumin/creatinine concentration ratio (Ualb/Ucreat) were calculated......, and 73%, 97%, and 73% for Ualb/Ucreat, respectively. CONCLUSIONS: It is concluded that measurement of the albumin/creatinine concentration ratio is a specific and quite sensitive alternative to measurement of the urinary albumin excretion rate in timed collections, when screening for microalbuminuria....

Podocytes degrade endocytosed albumin primarily in lysosomes.

Science.gov (United States)

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%, plysosomes are involved in the processing of endocytosed albumin in podocytes, and lysosomal dysfunction may contribute to podocyte injury and glomerulosclerosis in albuminuric diseases. Modifiers of lysosomal activity may have therapeutic potential in slowing the progression of glomerulosclerosis by enhancing the ability of podocytes to process and degrade albumin.

Podocytes Degrade Endocytosed Albumin Primarily in Lysosomes

Science.gov (United States)

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%, palbumin 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 glomerulosclerosis in albuminuric diseases. Modifiers of lysosomal activity may have therapeutic

Influence of haemodynamic disturbances caused by acceleration on distribution of 125J-albumin in eyes of experimental animals

International Nuclear Information System (INIS)

Kozuchowska, I.; Wojtkowiak, M.; Tajchert, J.

1975-01-01

Examination of radioactivity in eyes of experimental animals (50 guinea pigs) was performed in order to investigate the disturbances in the intraocular blood circulation under the influence of centripetal accelerations. After an intracordial injection of 125 J-albumin the animals were whirled, up to the moment of bradycardia pointing to a breakdown of compensatory reactions of the circulatory system. Particular groups of animals were frozen in fluid nitrogen in various time. Results showed an increase of permeability of the blood-aqueous barrier for ablumins. (author)

Studies on kinetics of albumin in uraemic patients on chronic haemodialysis: evidence of interstitial albumin wash-down

DEFF Research Database (Denmark)

Hildebrandt, P; Jensen, H A; Henriksen, Jens Henrik Sahl

1983-01-01

Albumin-kinetic studies were performed in nine uraemic patients without oedema on chronic haemodialysis and in seven normal controls in order to determine microvascular leakiness and thereby, during steady state, lymph drainage of albumin. Transvascular escape rate of albumin [TERalb i.......e. the fraction of intravascular mass (IVMalb) passing into, or returning from, the extravascular space per unit time] and the distribution ratio (DRalb) between IVMalb and total albumin mass were determined from intravenously injected radioiodinated serum albumin. Before haemodialysis, TERalb was significantly...... with respect to controls (mean 0 X 44, range 0 X 42-0 X 48, P less than 0 X 01), and the extravascular mass of albumin was significantly decreased (mean 27 X 9 mumol kg-1, range 14.1 - 41.2 v. mean 35.9, range 27.1 - 43.8, P less than 0.05). We interpret the results as to indicate increased transvascular...

Increased pulmonary vascular permeability as a cause of re-expansion edema in rabbits

International Nuclear Information System (INIS)

Pavlin, D.J.; Nessly, M.L.; Cheney, F.W.

1981-01-01

In order to study the mechanism(s) underlying re-expansion edema, we measured the concentration of labeled albumin (RISA) in the extravascular, extracellular water (EVECW) of the lung as a measure of pulmonary vascular permeability. Re-expansion edema was first induced by rapid re-expansion of rabbit lungs that had been collapsed for 1 wk by pneumothorax. The RISA in EVECW was expressed as a fraction of its plasma concentration: (RISA)L/(RISA)PL. The volume of EVECW (ml/gm dry lung) was measured using a 24 Na indicator. Results in re-expansion edema were compared with normal control lungs and with oleic acid edema as a model of permeability edema. In re-expanded lungs, EVECW (3.41 +/- SD 1.24 ml/g) and (RISA)L/(RISA)PL 0.84 +/- SD 0.15) were significantly increased when compared with normal control lungs (2.25 +/- 0.41 ml/g and 0.51 +/- 0.20, respectively). Results in oleic acid edema (5.66 +/- 2.23 ml/g and 0.84 +/- 0.23) were similar to re-expansion edema. This suggested that re-expansion edema is due to increased pulmonary vascular permeability caused by mechanical stresses applied to the lung during re-expansion

Albumin modification and fragmentation in renal disease.

Science.gov (United States)

Donadio, Carlo; Tognotti, Danika; Donadio, Elena

2012-02-18

Albumin is the most important antioxidant substance in plasma and performs many physiological functions. Furthermore, albumin is the major carrier of endogenous molecules and exogenous ligands. This paper reviews the importance of post-translational modifications of albumin and fragments thereof in patients with renal disease. First, current views and controversies on renal handling of proteins, mainly albumin, will be discussed. Post-translational modifications, namely the fragmentation of albumin found with proteomic techniques in nephrotic patients, diabetics, and ESRD patients will be presented and discussed. It is reasonable to hypothesize that proteolytic fragmentation of serum albumin is due to a higher susceptibility to proteases, induced by oxidative stress. The clinical relevance of the fragmentation of albumin has not yet been established. These modifications could affect some physiological functions of albumin and have a patho-physiological role in uremic syndrome. Proteomic analysis of serum allows the identification of over-expressed proteins and can detect post-translational modifications of serum proteins, hitherto hidden, using standard laboratory techniques. Copyright © 2011 Elsevier B.V. All rights reserved.

21 CFR 640.80 - Albumin (Human).

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Albumin (Human). 640.80 Section 640.80 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Albumin (Human) § 640.80 Albumin (Human). (a) Proper...

Leukotriene B4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo.

Science.gov (United States)

Colom, Bartomeu; Bodkin, Jennifer V; Beyrau, Martina; Woodfin, Abigail; Ody, Christiane; Rourke, Claire; Chavakis, Triantafyllos; Brohi, Karim; Imhof, Beat A; Nourshargh, Sussan

2015-06-16

Breaching endothelial cells (ECs) is a decisive step in the migration of leukocytes from the vascular lumen to the extravascular tissue, but fundamental aspects of this response remain largely unknown. We have previously shown that neutrophils can exhibit abluminal-to-luminal migration through EC junctions within mouse cremasteric venules and that this response is elicited following reduced expression and/or functionality of the EC junctional adhesion molecule-C (JAM-C). Here we demonstrate that the lipid chemoattractant leukotriene B4 (LTB4) was efficacious at causing loss of venular JAM-C and promoting neutrophil reverse transendothelial cell migration (rTEM) in vivo. Local proteolytic cleavage of EC JAM-C by neutrophil elastase (NE) drove this cascade of events as supported by presentation of NE to JAM-C via the neutrophil adhesion molecule Mac-1. The results identify local LTB4-NE axis as a promoter of neutrophil rTEM and provide evidence that this pathway can propagate a local sterile inflammatory response to become systemic. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Albumin grafting on polymer surfaces by gamma-irradiation

International Nuclear Information System (INIS)

Kamath, K.R.; Park, K.; DeMeo, D.

1993-01-01

Polymeric biomaterial surfaces were modified by albumin grafting to improve their blood compatibility. Albumin molecules were functionalized by introduction of double bonds. The functionalized albumin was covalently attached to polypropylene fibers, polycarbonate, and poly(vinyl chloride) by gamma-irradiation. ESCA and ATR/FTIR analysis of the control and grafted surfaces was conducted. Albumin grafting efficiency was found to be dependent on the gamma-irradiation time and the concentration of albumin as indicated by platelet adhesion studies. The grafted albumin molecules were not displaced when exposed to blood for prolonged time period. Finally, PLEXUS oxygenators grafted with albumin using this approach showed a significant reduction in platelet adhesion when compared to control

Developments in permeable and low permeability barriers

International Nuclear Information System (INIS)

Jefferis, S.A.; Norris, G.H.; Thomas, A.O.

1997-01-01

The concept of the reactive treatment zone whereby pollutants are attenuated as they move along a pathway in the ground has enabled a re-thinking of many of the concepts of containment. In particular it offers the potential for the control of the flux from a contaminated area by controlling the contaminant concentration in the pathway(s) as well as or instead of using a low permeability barrier. The paper outlines the basic concepts of the reactive treatment zone and the use of permeable and low permeability reactive systems. The paper then gives a case history of the installation of a permeable barrier using an in-situ reaction chamber

A facile route to glycated albumin detection.

Science.gov (United States)

Bohli, Nadra; Meilhac, Olivier; Rondeau, Philippe; Gueffrache, Syrine; Mora, Laurence; Abdelghani, Adnane

2018-07-01

In this paper we propose an easy way to detect the glycated form of human serum albumin which is biomarker for several diseases such as diabetes and Alzheimer. The detection platform is a label free impedimetric immunosensor, in which we used a monoclonal human serum albumin antibody as a bioreceptor and electrochemical impedance as a transducing method. The antibody was deposited onto a gold surface by simple physisorption technique. Bovine serum albumin was used as a blocking agent for non-specific binding interactions. Cyclic voltammetry and electrochemical impedance spectroscopy were used for the characterization of each layer. Human serum albumin was glycated at different levels with several concentrations of glucose ranging from 0 mM to 500 mM representing physiological, pathological (diabetic albumin) and suprapathological concentration of glucose. Through the calibration curves, we could clearly distinguish between two different areas related to physiological and pathological albumin glycation levels. The immunosensor displayed a linear range from 7.49% to 15.79% of glycated albumin to total albumin with a good sensitivity. Surface plasmon resonance imaging was also used to characterize the developed immunosensor. Copyright © 2018 Elsevier B.V. All rights reserved.

Renal albumin absorption in physiology and pathology.

Science.gov (United States)

Birn, H; Christensen, E I

2006-02-01

Albumin is the most abundant plasmaprotein serving multiple functions as a carrier of metabolites, hormones, vitamins, and drugs, as an acid/base buffer, as antioxidant and by supporting the oncotic pressure and volume of the blood. The presence of albumin in urine is considered to be the result of the balance between glomerular filtration and tubular reabsorption. Albuminuria has been accepted as an independent risk factor and a marker for renal as well as cardiovascular disease, and during the past decade, evidence has suggested that albumin itself may cause progression of renal disease. Thus, the reduction of proteinuria and, in particular, albuminuria has become a target in itself to prevent deterioration of renal function. Studies have shown albumin and its ligands to induce expression of inflammatory and fibrogenic mediators, and it has been hypothesized that increased filtration of albumin causes excessive tubular reabsorption, resulting in inflammation and fibrosis, resulting in the loss of renal function. In addition, it is known that tubular dysfunction in itself may cause albuminuria owing to decreased reabsorption of filtered albumin, and, recently, it has been suggested that significant amounts of albumin fragments are excreted in the urine as a result of tubular degradation. Thus, although both tubular and glomerular dysfunction influences renal handling of albumin, it appears that tubular reabsorption plays a central role in mediating the effects of albumin on renal function. The present paper will review the mechanisms for tubular albumin uptake and the possible implications for the development of renal disease.

99mTc-albumin can replace 125I-albumin to determine plasma volume repeatedly

DEFF Research Database (Denmark)

Bonfils, Peter K; Damgaard, Morten; Stokholm, Knud H

2012-01-01

OBJECTIVE: Plasma volume assessment may be of importance in several disorders. The purpose of the present study was to compare the reliability of plasma volume measurements by technetium-labeled human serum albumin ((99m)Tc-HSA) with a simultaneously performed plasma volume determination...... with iodine-labeled human serum albumin ((125)I-HSA). MATERIALS AND METHODS: In 15 healthy volunteers, simultaneous plasma volume measurements with (99m)Tc-HSA and (125)I-HSA were performed after ½ hour in the supine position. Blood samples were obtained 10, 15, 20, and 30 minutes after the injection...... for accurate retropolation from the plasma counts to time zero to correct for leakage of the isotopes from the circulation. RESULTS: The mean difference (bias) between plasma volume measured with (125)I-albumin and (99m)Tc-albumin was 8 ml (0.1 ml/kg) with limits of agreement (bias ±1.96 SD) ranging from -181...

Crustal permeability

Science.gov (United States)

Gleeson, Tom; Ingebritsen, Steven E.

2016-01-01

Permeability is the primary control on fluid flow in the Earth’s crust and is key to a surprisingly wide range of geological processes, because it controls the advection of heat and solutes and the generation of anomalous pore pressures.  The practical importance of permeability – and the potential for large, dynamic changes in permeability – is highlighted by ongoing issues associated with hydraulic fracturing for hydrocarbon production (“fracking”), enhanced geothermal systems, and geologic carbon sequestration.  Although there are thousands of research papers on crustal permeability, this is the first book-length treatment.  This book bridges the historical dichotomy between the hydrogeologic perspective of permeability as a static material property and the perspective of other Earth scientists who have long recognized permeability as a dynamic parameter that changes in response to tectonism, fluid production, and geochemical reactions. 

Repression of the albumin gene in Novikoff hepatoma cells

International Nuclear Information System (INIS)

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 [/sup 32/P]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

Fibrinogen adsorption on blocked surface of albumin.

Science.gov (United States)

Holmberg, Maria; Hou, Xiaolin

2011-05-01

We have investigated the adsorption of albumin and fibrinogen onto PET (polyethylene terephthalate) and glass surfaces and how pre-adsorption of albumin onto these surfaces can affect the adsorption of later added fibrinogen. For materials and devices being exposed to blood, adsorption of fibrinogen is often a non-wanted event, since fibrinogen is part of the clotting cascade and unspecific adsorption of fibrinogen can have an influence on the activation of platelets. Albumin is often used as blocking agent for avoiding unspecific protein adsorption onto surfaces in devices designed to handle biological samples, including protein solutions. It is based on the assumption that proteins adsorbs as a monolayer on surfaces and that proteins do not adsorb on top of each other. By labelling albumin and fibrinogen with two different radioactive iodine isotopes that emit gamma radiation with different energies, the adsorption of both albumin and fibrinogen has been monitored simultaneously on the same sample. Information about topography and coverage of adsorbed protein layers has been obtained using AFM (Atomic Force Microscopy) analysis in liquid. Our studies show that albumin adsorbs in a multilayer fashion on PET and that fibrinogen adsorbs on top of albumin when albumin is pre-adsorbed on the surfaces. Copyright © 2010 Elsevier B.V. All rights reserved.

Evidência de alterações de permeabilidade vascular na dengue: quando a dosagem de albumina sérica define o quadro? Plasma leakage detection in severe dengue: when serum albumin quantification plays a role?

Directory of Open Access Journals (Sweden)

Carlos A.A. Brito

2007-04-01

Full Text Available Evidência de extravasamento vascular decorrente do aumento da permeabilidade capilar caracteriza e diferencia febre hemorrágica da dengue. Este artigo avalia o valor de albumina sérica na detecção de alterações de permeabilidade vascular em casos de dengue. Quatorze pacientes diagnosticados com febre hemorrágica da dengue em dois hospitais privados em Recife, Brasil, entre janeiro e maio de 2002 foram seguidos com dosagens diárias de hematócrito e albumina sérica. Ultra-son e Raio X de tórax foram realizados. Oito (57% casos apresentaram hemoconcentração de 20% ou mais. Hipoalbuminemia foi detectado em dez (71% pacientes. Dosagem de albumina sérica aumentou a detecção de alterações de permeabilidade em seis (43% casos na qual a hemoconcentração foi inferior a 20% e os sintomas foram compatíveis com um a resposta imune exacerbada. Raio-X foi normal em todos os casos. A utilização, portanto, de dosagem de albumina sérica aumenta a sensibilidade de detecção de casos de febre hemorrágica da dengue.Evidence of vascular leakage due to increased capillary permeability characterizes and differentiates dengue hemorrhagic fever. This article assesses the value of serum albumin for detecting vascular permeability abnormalities in dengue cases. Fourteen patients diagnosed with dengue hemorrhagic fever at two private hospitals in Recife, Brazil, between January and May 2002 were followed up with daily hematocrit and serum albumin assays. Ultrasound scans and chest X-rays were also performed. Eight (57% of the cases presented hemoconcentration of 20% or more. Hypoalbuminemia was detected in ten patients (71%. Serum albumin assays increased the detection of permeability abnormalities in six cases (43% in which the hemoconcentration was less than 20% and the symptoms were compatible with an exacerbated immune response. The X-rays were normal in all cases. Thus, the use serum albumin quantification increased the sensitivity of dengue

Radiolabeling Of Albumin Particles With Yttrium-90

International Nuclear Information System (INIS)

Nguyen Thi Thu; Nguyen Thi Khanh Giang; Bui Van Cuong, Vo Thi Cam Hoa

2011-01-01

This paper presents the process of the radiolabeling of microaggregated albumin particles with radionuclide Yttrium-90 using the directed method. The albumin microsphere kit was prepared in sodium phosphate buffer. The original solution includes 2 mg albumin particle and 0.5 mg stannous chloride dihydrate. The albumin particles size was ranged from 5 ?m to 30 ?m. The mixture was washed three times with phosphate buffer saline, pH 7.2 by centrifugation and suspended in 0.5 M sodium acetate buffer, pH 6. Yttrium - 90 in 1.0 M acetic acid was collected from 90 Sr/ 90 Y generator. The labeling of the particles with Y-90 (185 MBq) was performed at pH 5.5 in acetate buffer with agitating for 60 min at room temperature. The labeled albumin suspensions were centrifuged at 3000 rpm for 15 min. Labeling yields was calculated using centrifugation, filtration and compared with paper chromatography, which is developed in the Tris Acetic EDTA. In this system, the unbound of Y-90 migrates to an R f of 0.9-1.0 and the radiolabeled albumin particles remains at the point of origin (R f = 0). The size of 90 Y-albumin particles was compared with the albumin particles in the original solution to be sure that they did not change during the labeling treatment. The radiolabeling yields were more than 80%. The labeled compound was dialysis in phosphate buffer. The radiochemical purity was 98%. The 90 Y- albumin is an ideal radiopharmaceutical for potential use in malignant cancer treatment as brachytherapy. (author)

Development of ELISA kit for rat albumin

International Nuclear Information System (INIS)

Yuan Zhigang; Han Shiquan; Liu Yibing; Xu Wenge; Jia Juanjuan

2009-01-01

The Anti-rat albumin serum was prepared by immunized the sheep with rat albumin. A ELISA method was established for rat albumin. The measurement range of the assay was 1-50 mg/L, sensitivity of the assay was 0.42 mg/L, recovery rate was 85.0%-106.0%. Intra-and inter-assay variation coefficients were <8.9% and <12.8% respectively. The correlation coefficients between measured and expected values were 0.999 after serial dilution of the urine samples with high concentrations of rat albumin. A good correlation was observed between the ELISA and RIA methods, and the kit for rat albumin might provide a convenience in exploitation of renal drugs and experimental injury of the kidney. (authors)

The role of albumin conformation in the binding of diazepam to human serum albumin

NARCIS (Netherlands)

Wilting, J.; Hart, B.J. 't; Gier, J.J. de

2006-01-01

The effect of hydrogen, chloride and calcium ions on the binding of diazepare to human serum albumin has been studied by circular dichroism and equilibrium dialysis. In all cases the molar ellipticity of the diazepam-albumin complex increases with pH over the pH range 5 to 9. Under these

Thyroid albumin originates from blood

NARCIS (Netherlands)

de Vijlder, J. J.; Veenboer, G. J.; van Dijk, J. E.

1992-01-01

Iodoalbumin has been found in the goiter of Dutch goats with a thyroglobulin synthesis defect. Immunohistochemical studies showed that in the goiter the percentage of follicles containing albumin was higher than that in normal thyroid glands. In the albumin-containing follicles of normal and

Albumin-based drug delivery

DEFF Research Database (Denmark)

Larsen, Maja Thim; Kuhlmann, Matthias; Hvam, Michael Lykke

2016-01-01

The effectiveness of a drug is dependent on accumulation at the site of action at therapeutic levels, however, challenges such as rapid renal clearance, degradation or non-specific accumulation requires drug delivery enabling technologies. Albumin is a natural transport protein with multiple ligand...... binding sites, cellular receptor engagement, and a long circulatory half-life due to interaction with the recycling neonatal Fc receptor. Exploitation of these properties promotes albumin as an attractive candidate for half-life extension and targeted intracellular delivery of drugs attached by covalent...... conjugation, genetic fusions, association or ligand-mediated association. This review will give an overview of albumin-based products with focus on the natural biological properties and molecular interactions that can be harnessed for the design of a next-generation drug delivery platform....

An agent-based model of leukocyte transendothelial migration during atherogenesis.

Directory of Open Access Journals (Sweden)

Rita Bhui

2017-05-01

Full Text Available A vast amount of work has been dedicated to the effects of hemodynamics and cytokines on leukocyte adhesion and trans-endothelial migration (TEM and subsequent accumulation of leukocyte-derived foam cells in the artery wall. However, a comprehensive mechanobiological model to capture these spatiotemporal events and predict the growth and remodeling of an atherosclerotic artery is still lacking. Here, we present a multiscale model of leukocyte TEM and plaque evolution in the left anterior descending (LAD coronary artery. The approach integrates cellular behaviors via agent-based modeling (ABM and hemodynamic effects via computational fluid dynamics (CFD. In this computational framework, the ABM implements the diffusion kinetics of key biological proteins, namely Low Density Lipoprotein (LDL, Tissue Necrosis Factor alpha (TNF-α, Interlukin-10 (IL-10 and Interlukin-1 beta (IL-1β, to predict chemotactic driven leukocyte migration into and within the artery wall. The ABM also considers wall shear stress (WSS dependent leukocyte TEM and compensatory arterial remodeling obeying Glagov's phenomenon. Interestingly, using fully developed steady blood flow does not result in a representative number of leukocyte TEM as compared to pulsatile flow, whereas passing WSS at peak systole of the pulsatile flow waveform does. Moreover, using the model, we have found leukocyte TEM increases monotonically with decreases in luminal volume. At critical plaque shapes the WSS changes rapidly resulting in sudden increases in leukocyte TEM suggesting lumen volumes that will give rise to rapid plaque growth rates if left untreated. Overall this multi-scale and multi-physics approach appropriately captures and integrates the spatiotemporal events occurring at the cellular level in order to predict leukocyte transmigration and plaque evolution.

Composition comprising radioactive labeled-fibrinogen and albumin

International Nuclear Information System (INIS)

Charlton, J.C.; Gravett, D.L.

1976-01-01

The stability of fibrinogen is improved by mixing it with albumin, preferably at least 5 parts by weight of albumin per part by weight of fibrinogen. By this invention, iodinated ( 125 I) human fibrinogen can be stabilized with human serum albumin for use in the diagnosis of thrombi

Leukotriene B4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo

Science.gov (United States)

Colom, Bartomeu; Bodkin, Jennifer V.; Beyrau, Martina; Woodfin, Abigail; Ody, Christiane; Rourke, Claire; Chavakis, Triantafyllos; Brohi, Karim; Imhof, Beat A.; Nourshargh, Sussan

2015-01-01

Summary Breaching endothelial cells (ECs) is a decisive step in the migration of leukocytes from the vascular lumen to the extravascular tissue, but fundamental aspects of this response remain largely unknown. We have previously shown that neutrophils can exhibit abluminal-to-luminal migration through EC junctions within mouse cremasteric venules and that this response is elicited following reduced expression and/or functionality of the EC junctional adhesion molecule-C (JAM-C). Here we demonstrate that the lipid chemoattractant leukotriene B4 (LTB4) was efficacious at causing loss of venular JAM-C and promoting neutrophil reverse transendothelial cell migration (rTEM) in vivo. Local proteolytic cleavage of EC JAM-C by neutrophil elastase (NE) drove this cascade of events as supported by presentation of NE to JAM-C via the neutrophil adhesion molecule Mac-1. The results identify local LTB4-NE axis as a promoter of neutrophil rTEM and provide evidence that this pathway can propagate a local sterile inflammatory response to become systemic. PMID:26047922

Albumin extravasation in bicuculline-induced blood-brain barrier dysfunction

International Nuclear Information System (INIS)

Persson, L.I.; Rosengren, L.E.; Johansson, B.B.

1980-01-01

The extravasation of endogeneous rat albumin and exogeneous 125 I-labeled human serum albumin was compared in rats subjected to bicuculline-induced blood-brain barrier dysfunction. The correlation between rocket immunoelectrophoretic assays of endogeneous rat albumin and 125 I-labeled human serum albumin, assayed by gamma scintillation counting, was good irrespective of whether 125 I-labeled albumin was studied in whole brain tissue or in brain homogenates. The ratio of brain to serum albumin was similar with the two assay methods. (author)

Preparation of Tc-99m-macroaggregated albumin from recombinant human albumin for lung perfusion imaging.

Science.gov (United States)

Hunt, A P; Frier, M; Johnson, R A; Berezenko, S; Perkins, A C

2006-01-01

Human serum albumin (HSA) extracted from pooled blood taken from human donors is used in the production of (99m)Tc-labelled macroaggregated albumin (MAA) for lung perfusion imaging. However, concerns for the safety of blood-derived products due to potential contamination by infective agents (e.g. new variant CJD), make alternative production methods necessary. Recombinant DNA technology is a promising method of albumin production avoiding problems associated with human-derived HSA. This paper presents results comparing MAA prepared from recombinant human albumin (rHA, Recombumin) (rMAA) with in-house produced HSA MAA (hMAA) and commercially available MAA (cMAA). (99m)Tc-MAA was prepared using previously published production methods by heating a mixture of albumin and stannous chloride in acetate buffer (pH 5.4) at 70 degrees C for 20 min. Parameters investigated include aggregate size, radiolabelling efficiency, radiochemical and aggregate stability at 4 degrees C and in vitro (in whole human blood) at 37 degrees C and biodistribution studies. Results showed that rMAA could be produced with similar morphology, labelling efficiency and stability to hMAA and cMAA. Our findings confirm that rHA shows significant potential as a direct replacement for HSA in commercially available MAA.

Effect of permeability enhancers on paracellular permeability of acyclovir.

Science.gov (United States)

Ates, Muge; Kaynak, Mustafa Sinan; Sahin, Selma

2016-06-01

According to Biopharmaceutics Classification System (BCS), acyclovir is a class III (high solubility, low permeability) compound, and it is transported through paracellular route by passive diffusion. The aim of this study was to investigate the effect of various pharmaceutical excipients on the intestinal permeability of acyclovir. The single-pass in-situ intestinal perfusion (SPIP) method was used to estimate the permeability values of acyclovir and metoprolol across different intestinal segments (jejunum, ileum and colon). Permeability coefficient (Peff ) of acyclovir was determined in the absence and presence of a permeation enhancer such as dimethyl β-cyclodextrin (DM-β-CD), sodium lauryl sulfate (SLS), sodium caprate (Cap-Na) and chitosan chloride. All enhancers increased the permeability of paracellularly transported acyclovir. Although Cap-Na has the highest permeability-enhancing effect in all segments, permeation-enhancing effect of chitosan and SLS was only significant in ileum. On the other hand, DM-β-CD slightly decreased the permeability in all intestinal segments. These findings have potential implication concerning the enhancement of absorption of paracellularly transported compounds with limited oral bioavailability. In the case of acyclovir, Cap-Na either alone or in combination with SLS or chitosan has the potential to improve its absorption and bioavailability and has yet to be explored. © 2016 Royal Pharmaceutical Society.

A tripartite approach identifies the major sunflower seed albumins.

Science.gov (United States)

Jayasena, Achala S; Franke, Bastian; Rosengren, Johan; Mylne, Joshua S

2016-03-01

We have used a combination of genomic, transcriptomic, and proteomic approaches to identify the napin-type albumin genes in sunflower and define their contributions to the seed albumin pool. Seed protein content is determined by the expression of what are typically large gene families. A major class of seed storage proteins is the napin-type, water soluble albumins. In this work we provide a comprehensive analysis of the napin-type albumin content of the common sunflower (Helianthus annuus) by analyzing a draft genome, a transcriptome and performing a proteomic analysis of the seed albumin fraction. We show that although sunflower contains at least 26 genes for napin-type albumins, only 15 of these are present at the mRNA level. We found protein evidence for 11 of these but the albumin content of mature seeds is dominated by the encoded products of just three genes. So despite high genetic redundancy for albumins, only a small sub-set of this gene family contributes to total seed albumin content. The three genes identified as producing the majority of sunflower seed albumin are potential future candidates for manipulation through genetics and breeding.

[Protein losing enteropathy (PLE) detected by Tc99m-labelled human serum albumin abdominal scintigraphy--case report].

Science.gov (United States)

Hubalewska-Hoła, Alicja; Sowa-Staszczak, Anna; Szczerbiński, Tomasz; Lis, Grzegorz; Huszno, Bohdan; Szybiński, Zbigniew

2003-01-01

Protein losing enteropathy (PLE) is a gastrointestinal disorder that is associated with excessive loss of plasma protein into the gut resulting from abnormal mucosal permeability. The disease is usually caused by inflammation. The loss of protein in PLE is a nonselective process affecting albumin, globulin and transferrin. Abdominal scintigraphy with human serum albumin marked by Tc99m seems to be an easy and sensitive method for diagnosing PLE. An 4-year-old girl was presented to an outside Pediatric Department due to hypoproteinemia and recurrent pneumonia which had caused several prior hospitalizations. The laboratory tests revealed hypoproteinemia, hypoalbuminemia, low level of IgG, sideropenia, and a decreased level of T lymphocytes. The loss of protein into the gut was confirmed by fecal clearance of alfa-1 antitrypsin. Only nonspecific inflammation was detected by biopsy of the small intestine. These clinical and laboratory findings, quickly decreasing IgG and albumin levels in spite of i.v. supplementation and the lack of proteinuria permitted PLE diagnosis. The abdominal scintigraphy was planned to assess and localise protein losing through GIT and for strategy of possible surgical treatment. Abdominal dynamic scintigraphy was performed immediately after the injection of 300 MBq Tc99m human albumin. 90 images were taken within 180 minutes. Delayed abdominal images were obtained 6 and 24 hours after the tracer injection. Anterior abdominal scintigraphy showed pathological activity of Tc99m-albumin in small bowel in the upper left segment of the abdomen in the 40th minute after injection. Extensive accumulation of albumin was seen in the 160th minute. Delayed images, after 3 and 6 hours, revealed translocation of the tracer into the lower right abdominal segment. The further passage and tracer concentration was detected in ascendant and transverse colon. Based on the laboratory tests and scintigraphic images the girl was suspected to have segmental

Proximal Tubules Have the Capacity to Regulate Uptake of Albumin.

Science.gov (United States)

Wagner, Mark C; Campos-Bilderback, Silvia B; Chowdhury, Mahboob; Flores, Brittany; Lai, Xianyin; Myslinski, Jered; Pandit, Sweekar; Sandoval, Ruben M; Wean, Sarah E; Wei, Yuan; Satlin, Lisa M; Wiggins, Roger C; Witzmann, Frank A; Molitoris, Bruce A

2016-02-01

Evidence from multiple studies supports the concept that both glomerular filtration and proximal tubule (PT) reclamation affect urinary albumin excretion rate. To better understand these roles of glomerular filtration and PT uptake, we investigated these processes in two distinct animal models. In a rat model of acute exogenous albumin overload, we quantified glomerular sieving coefficients (GSC) and PT uptake of Texas Red-labeled rat serum albumin using two-photon intravital microscopy. No change in GSC was observed, but a significant decrease in PT albumin uptake was quantified. In a second model, loss of endogenous albumin was induced in rats by podocyte-specific transgenic expression of diphtheria toxin receptor. In these albumin-deficient rats, exposure to diphtheria toxin induced an increase in albumin GSC and albumin filtration, resulting in increased exposure of the PTs to endogenous albumin. In this case, PT albumin reabsorption was markedly increased. Analysis of known albumin receptors and assessment of cortical protein expression in the albumin overload model, conducted to identify potential proteins and pathways affected by acute protein overload, revealed changes in the expression levels of calreticulin, disabled homolog 2, NRF2, angiopoietin-2, and proteins involved in ATP synthesis. Taken together, these results suggest that a regulated PT cell albumin uptake system can respond rapidly to different physiologic conditions to minimize alterations in serum albumin level. Copyright © 2016 by the American Society of Nephrology.

DETERMINATION OF SERUM ALBUMIN WITH ...

African Journals Online (AJOL)

The reaction of tribromoarsenazo(TB-ASA) with serum albumin in the presence of emulgent OP was studied by spectrophotometry. In a Britton-Robinson buffer solution at pH 2.9, tribromoarsenazo and bovine serum albumin can immediately form a red compound in the presence of emulgent OP with a maximum absorption ...

Albumin-drug interaction and its clinical implication.

Science.gov (United States)

Yamasaki, Keishi; Chuang, Victor Tuan Giam; Maruyama, Toru; Otagiri, Masaki

2013-12-01

Human serum albumin acts as a reservoir and transport protein for endogenous (e.g. fatty acids or bilirubin) and exogenous compounds (e.g. drugs or nutrients) in the blood. The binding of a drug to albumin is a major determinant of its pharmacokinetic and pharmacodynamic profile. The present review discusses recent findings regarding the nature of drug binding sites, drug-albumin binding in certain diseased states or in the presence of coadministered drugs, and the potential of utilizing albumin-drug interactions in clinical applications. Drug-albumin interactions appear to predominantly occur at one or two specific binding sites. The nature of these drug binding sites has been fundamentally investigated as to location, size, charge, hydrophobicity or changes that can occur under conditions such as the content of the endogenous substances in question. Such findings can be useful tools for the analysis of drug-drug interactions or protein binding in diseased states. A change in protein binding is not always a problem in terms of drug therapy, but it can be used to enhance the efficacy of therapeutic agents or to enhance the accumulation of radiopharmaceuticals to targets for diagnostic purposes. Furthermore, several extracorporeal dialysis procedures using albumin-containing dialysates have proven to be an effective tool for removing endogenous toxins or overdosed drugs from patients. Recent findings related to albumin-drug interactions as described in this review are useful for providing safer and efficient therapies and diagnoses in clinical settings. This article is part of a Special Issue entitled Serum Albumin. Copyright © 2013 Elsevier B.V. All rights reserved.

Permeability of blood-tear barrier to fluorescein and albumin after application of platelet-activating factor to the eye of the guinea pig

Directory of Open Access Journals (Sweden)

J. L. Van Delft

1997-01-01

Full Text Available One of the inflammatory responses of the eye to local application of platelet-activating factor (PAF is oedema of the conjunctiva, caused by extravasation of plasma. Aim of the study was to investigate if fluorescein would leak from the blood into the tears together with plasma protein after application of PAF to the eye. Fluorescein was given intraperitoneally 30 min prior to application of 25 μl of 0.1% solution of PAF. Thirty min after PAF the tear film was collected by washing the surface of the eye with 25 μl of phosphate buffered saline (PBS. Fluorescein in eye washings and in plasma was measured by fluorophotometry and albumin by immunodiffusion. Both fluorescein and albumin appeared in a related fashion in tears, being absent in washings of placebo-treated control eyes. Extravasation of fluorescein can be used as a measure for plasma leakage in the conjunctiva with the advantage over the Evans Blue method that the former is a non-invasive method.

Preparation and characterization of microspheres of albumin-heparin conjugates

NARCIS (Netherlands)

Kwon, Glen S.; Bae, You Han; Kim, Sung Wan; Cremers, Harry; Cremers, H.F.M.; Feijen, Jan

1991-01-01

Albumin-heparin microspheres have been prepared as a new drug carrier. A soluble albumin-heparin conjugate was synthesized by forming amide bonds between human serum albumin and heparin. After purification the albumin-heparin conjugate was crosslinked in a water-in-oil emulsion to form

Fibrinogen adsorption on blocked surface of albumin

DEFF Research Database (Denmark)

Holmberg, Maria; Hou, Xiaolin

2011-01-01

We have investigated the adsorption of albumin and fibrinogen onto PET (polyethylene terephthalate) and glass surfaces and how pre-adsorption of albumin onto these surfaces can affect the adsorption of later added fibrinogen. For materials and devices being exposed to blood, adsorption...... of fibrinogen is often a non-wanted event, since fibrinogen is part of the clotting cascade and unspecific adsorption of fibrinogen can have an influence on the activation of platelets. Albumin is often used as blocking agent for avoiding unspecific protein adsorption onto surfaces in devices designed to handle...... energies, the adsorption of both albumin and fibrinogen has been monitored simultaneously on the same sample. Information about topography and coverage of adsorbed protein layers has been obtained using AFM (Atomic Force Microscopy) analysis in liquid. Our studies show that albumin adsorbs in a multilayer...

The development of radioimmunoassay kit for rat albumin

International Nuclear Information System (INIS)

Yuan Zhigang; Han Shiquan; Liu Yibing; Xu Wenge

2006-01-01

The Anti-rat albumin serum is prepared by immunized the sheep with rat albumin. A radioimmunoassay method is established for rat albumin. The measurement range of the assay is 1-50 mg/L, sensitivity of the assay is 0.12 mg/L, recovery rate is 97.8%- 108.4%. Intra- and inter-assay variation coefficients are <4.0% and <8.2% respectively. The correlation coefficients between measured and expected values are more than 0.990 after serial dilution of the urine samples with high concentrations of rat albumin. The kit for rat albumin might provide a convenience in exploitation of renal drugs and experimental in- jury of the kidney. (authors)

Zonulin as prehaptoglobin2 regulates lung permeability and activates the complement system.

Science.gov (United States)

Rittirsch, Daniel; Flierl, Michael A; Nadeau, Brian A; Day, Danielle E; Huber-Lang, Markus S; Grailer, Jamison J; Zetoune, Firas S; Andjelkovic, Anuska V; Fasano, Alessio; Ward, Peter A

2013-06-15

Zonulin is a protein involved in the regulation of tight junctions (TJ) in epithelial or endothelial cells. Zonulin is known to affect TJ in gut epithelial cells, but little is known about its influences in other organs. Prehaptoglobin2 has been identified as zonulin and is related to serine proteases (MASPs, C1qrs) that activate the complement system. The current study focused on the role of zonulin in development of acute lung injury (ALI) in C57BL/6 male mice following intrapulmonary deposition of IgG immune complexes. A zonulin antagonist (AT-1001) and a related peptide with permeability agonist activities (AT-1002) were employed and given intratracheally or intravenously. Also, zonulin was blocked in lung with a neutralizing antibody. In a dose-dependent manner, AT-1001 or zonulin neutralizing antibody attenuated the intensity of ALI (as quantitated by albumin leak, neutrophil accumulation, and proinflammatory cytokines). A similar pattern was found using the bacterial lipopolysaccharide model of ALI. Using confocal microscopy on sections of injured lungs, staining patterns for TJ proteins were discontinuous, reduced, and fragmented. As expected, the leak of blood products into the alveolar space confirmed the passage of 3 and 20 kDa dextran, and albumin. In contrast to AT-1001, application of the zonulin agonist AT-1002 intensified ALI. Zonulin both in vitro and in vivo induced generation of complement C3a and C5a. Collectively, these data suggest that zonulin facilitates development of ALI both by enhancing albumin leak and complement activation as well as increased buildup of neutrophils and cytokines during development of ALI.

Reabsorption kinetics of albumin from pleural space of dogs

International Nuclear Information System (INIS)

Miniati, M.; Parker, J.C.; Pistolesi, M.; Cartledge, J.T.; Martin, D.J.; Giuntini, C.; Taylor, A.E.

1988-01-01

The reabsorption of albumin from the pleural space was measured in eight dogs receiving 0.5 ml intrapleural injection of 131 I-labeled albumin and a simultaneous intravenous injection of 125 I-labeled albumin. Plasma curves for both tracers were obtained over 24 h. The 125 I-albumin curve served as input function of albumin for interstitial spaces, including pleura, whereas the 131 I-albumin curve represented the output function from pleural space. The frequency function of albumin transit times from pleural space to plasma was obtained by deconvolution of input-output plasma curves. Plasma recovery of 131 I-albumin was complete by 24 h, and the mean transit time from pleura to plasma averaged 7.95 +/- 1.57 (SD) h. Albumin reabsorption occurred mainly via lymphatics as indicated by experiments in 16 additional dogs in which their right lymph ducts or thoracic ducts were ligated before intrapleural injection. A pleural lymph flow of 0.020 +/- 0.003 (SD) ml.kg-1.h-1 was estimated, which is balanced by a comparable filtration of fluid into the pleural space. This suggests that, under physiological conditions, the subpleural lymphatics represent an important control mechanism of pleural liquid pressure

Albumin synthesis in protein energy malnutrition

Energy Technology Data Exchange (ETDEWEB)

Duggan, C; Hardy, S; Kleinman, R E [Harvard Medical School, Boston, MA (United States); Lembcke, J [Instituto de Investigacion Nutricional, La Molina, Lima (Peru); Young, V E [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Lab. of Human Nutrition

1994-12-31

The dietary treatment of protein-energy malnutrition (PEM) has been designed on an empirical basis, with outcomes for successful management including body weight gain and resolution of apathy. We propose using the measurements of protein synthesis as a more objective measure of renourishment. We will therefore randomize a group of malnourished children (weigh-for-height Z score <-2.0) to receive either a standard (10% of calories as protein) or increased (15%) amount of dietary protein early in their recovery phase. We will calculate albumin synthesis rates via the flooding dose technique, using {sup 13}C-leucine and serial measurements of {sup 13}C-enrichment of albumin. Isotope infusions will be performed on days one and three, following a standard three hour fast. Since albumin synthesis is reduced under the influence of cytokines which mediate the inflammatory response, results will be stratified according to the presence or absence of clinically apparent infections. We hypothesize that the provision of added dietary protein will optimize albumin synthesis rates in PEM as well as attenuate the reduction in albumin synthesis seen in the presence of infections. (author). 20 refs.

Suitability of Torrent Permeability Tester to measure air-permeability of covercrete

Energy Technology Data Exchange (ETDEWEB)

Andrade, C.; Gonzales-Gasca, C. [Institute of Construction Sciences ' Eduardo Torroja' , Madrid (Spain); Torrent, R. [Portland Cement Institute, (Argentina)

2000-07-01

Suitability of the Torrent Permeability Tester (TPT) to measure the permeability of covercrete to air, both in the laboratory and the field, is investigated, and test results obtained in laboratory studies are discussed. The tests performed included the determination of air permeability (TPT method), oxygen permeability (Cembureau method) and capillary suction, rapid chloride permeability test (ASTM C 1202), as well as a one-year carbonation depth test. Concrete specimens of various compositions and curing regimes were used in the tests; the gas-permeability tests were repeated on the same specimens after 28 days, than again at 6 months and 12 months. Test results confirmed the suitability of the TPT as a useful tool in the characterization of the quality the of concrete cover. It was found to be sensitive to changes in concrete quality; repeatable for sensitive properties such as gas permeability ; also, it was found to correlate well with other durability-related properties. 10 refs., 8 tabs., 8 figs.

Drug binding properties of neonatal albumin

DEFF Research Database (Denmark)

Brodersen, R; Honoré, B

1989-01-01

Neonatal and adult albumin was isolated by gel chromatography on Sephacryl S-300, from adult and umbilical cord serum, respectively. Binding of monoacetyl-diamino-diphenyl sulfone, warfarin, sulfamethizole, and diazepam was studied by means of equilibrium dialysis and the binding data were analyzed...... by the method of several acceptable fitted curves. It was found that the binding affinity to neonatal albumin is less than to adult albumin for monoacetyl-diamino-diphenyl sulfone and warfarin. Sulfamethizole binding to the neonatal protein is similarly reduced when more than one molecule of the drug is bound...

Albumin metabolism in health and disease

International Nuclear Information System (INIS)

Kirsch, R.E.; Saunders, S.J.; Brock, J.F.

1979-01-01

Studies performed at the University of Cape Town on the metabolism of albumin have been reviewed. The control of albumin metabolism in protein energy malnutrition, in acute exposure to alcohol and after partial hepatectomy in the rat is discussed

Albumin metabolism in health and disease

Energy Technology Data Exchange (ETDEWEB)

Kirsch, R E; Saunders, S J; Brock, J F [Cape Town Univ. (South Africa). Dept. of Medicine

1979-11-24

Studies performed at the University of Cape Town on the metabolism of albumin have been reviewed. The control of albumin metabolism in protein energy malnutrition, in acute exposure to alcohol and after partial hepatectomy in the rat is discussed.

2.6. Sorption of serum albumin by ethynyl-piperidol hydrogels

International Nuclear Information System (INIS)

Khalikov, D.Kh.

2012-01-01

The sorption of serum albumin by ethynyl-piperidol hydrogels was studied in this article. Albumins adsorption on the surface of solids was considered. The capacity of cross-linked ethynyl piperidol polymers to the serum albumin was considered as well. The kinetic curves of sorption of human serum albumin by triple copolymer of isopropenyl trimethyl ethynyl piperidol were constructed. Sorption activity of ethynyl-piperidol polymers depending on ph of solution of human serum albumin were defined. Influence of solution ionic strength on sorption of human serum albumin was defined as well. The desorption of human serum albumin from the complexes with hydrogels was examined.

Structural and permeability characterization of biosynthetic PVA hydrogels designed for cell-based therapy.

Science.gov (United States)

Nafea, Eman H; Poole-Warren, Laura A; Martens, Penny J

2014-01-01

Incorporation of extracellular matrix (ECM) components to synthetic hydrogels has been shown to be the key for successful cell encapsulation devices, by providing a biofunctional microenvironment for the encapsulated cells. However, the influence of adding ECM components into synthetic hydrogels on the permeability as well as the physical and mechanical properties of the hydrogel has had little attention. Therefore, the aim of this study was to investigate the effect of incorporated ECM analogues on the permeability performance of permselective synthetic poly(vinyl alcohol) (PVA) hydrogels in addition to examining the physico-mechanical characteristics. PVA was functionalized with a systematically increased number of methacrylate functional groups per chain (FG/c) to tailor the permselectivity of UV photopolymerized hydrogel network. Heparin and gelatin were successfully incorporated into PVA network at low percentage (1%), and co-hydrogels were characterized for network properties and permeability to bovine serum albumin (BSA) and immunoglobulin G (IgG) proteins. Incorporation of these ECM analogues did not interfere with the base PVA network characteristics, as the controlled hydrogel mesh sizes, swelling and compressive modulii remained unchanged. While the permeation profiles of both BSA and IgG were not affected by the addition of heparin and gelatin as compared with pure PVA, increasing the FG/c from 7 to 20 significantly limited the diffusion of the larger IgG. Consequently, biosynthetic hydrogels composed of PVA with high FG/c and low percent ECM analogues show promise in their ability to be permselective for various biomedical applications.

A New Application for Albumin Dialysis in Extracorporeal Organ Support: Characterization of a Putative Interaction Between Human Albumin and Proinflammatory Cytokines IL-6 and TNFα.

Science.gov (United States)

Pfensig, Claudia; Dominik, Adrian; Borufka, Luise; Hinz, Michael; Stange, Jan; Eggert, Martin

2016-04-01

Albumin dialysis in extracorporeal organ support is often performed in the treatment of liver failure as it facilitates the removal of toxic components from the blood. Here, we describe a possible effect of albumin dialysis on proinflammatory cytokine levels in vitro. Initially, albumin samples were incubated with different amounts of cytokines and analyzed by enzyme-linked immunosorbent assay (ELISA). Analysis of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) levels indicated that increased concentrations of albumin reduce the measureable amount of the respective cytokines. This led to the hypothesis that the used proinflammatory cytokines may interact with albumin. Size exclusion chromatography of albumin spiked with cytokines was carried out using high-performance liquid chromatography analysis. The corresponding fractions were evaluated by immunoblotting. We detected albumin and cytokines in the same fractions indicating an interaction of the small-sized cytokines IL-6 and TNFα with the larger-sized albumin. Finally, a two-compartment albumin dialysis in vitro model was used to analyze the effect of albumin on proinflammatory cytokines in the recirculation circuit during 6-h treatment. These in vitro albumin dialysis experiments indicated a significant decrease of IL-6, but not of TNFα, when albumin was added to the dialysate solution. Taken together, we were able to show a putative in vitro interaction of human albumin with the proinflammatory cytokine IL-6, but with less evidence for TNFα, and demonstrated an additional application for albumin dialysis in liver support therapy where IL-6 removal might be indicated. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Albumin supplementation for hypoalbuminemia following burns: unnecessary and costly!

Science.gov (United States)

Melinyshyn, Alex; Callum, Jeannie; Jeschke, Marc C; Cartotto, Robert

2013-01-01

Following fluid resuscitation, patients with major burns frequently develop prolonged hypoalbuminemia. It is not known whether this should be corrected by albumin supplementation. The purpose of this study was to determine whether there are any benefits associated with albumin supplementation to correct hypoalbuminemia in burned adults. We conducted a retrospective comparison of patients with burns ≥ 20% TBSA admitted to an adult regional American Burn Association-verified burn center, from May 1, 2009, to September 30, 2010, where we did not routinely supplement albumin (control group), with patients admitted from October 1, 2010, to May 30, 2011, where we had instituted a protocol in which 5% human albumin was provided to maintain serum albumin levels >20 g/L (albumin group). Comparisons were made from postburn (PB) day 2 to day 30 inclusive. There were no significant differences between control (n = 26) and albumin (n = 17) in age (48 ± 15 vs 45 ± 21 years; P = .56), burn size (33 ± 13 vs 34 ± 13 %TBSA; P = .831), or full thickness burn size (19 ± 19 vs 23 ± 19 %TBSA; P = .581). Inhalation injury was significantly more frequent in the albumin group than in controls (71% vs 31%; P = .01). The groups did not differ significantly in need for admission escharotomy, admission Sequential Organ Failure Assessment (SOFA) score, number of surgical procedures/first 30 days, or 24 and 48 hours fluid resuscitation volume requirements. The overall mean daily serum albumin level from PB day 2 to 30 in the albumin group (26.9 ± 3.0 g/L) was significantly greater than in controls (21.9 ± 4.4 g/L; P patient per day). We conclude that routine supplementation of 5% human albumin to maintain a serum albumin level ≥ 20 g/L in burn patients is expensive and provides no benefit.

Exploration of permeability and antifouling performance on modified cellulose acetate ultrafiltration membrane with cellulose nanocrystals.

Science.gov (United States)

Lv, Jinling; Zhang, Guoquan; Zhang, Hanmin; Yang, Fenglin

2017-10-15

Cellulose nanocrystals (CNCs) were introduced into cellulose diacetate (CDA) matrix via immerged phase-inversion process, aiming to improve the filtration and antifouling performance of CNCs/CDA blending membrane. The effects of CNCs on membrane morphologies, hydrophilicity, permeability and antifouling property were investigated. Results showed that the incorporation of CNCs into CDA membrane could effectively enhance the permeability and antifouling property of CNCs/CDA blending membrane by optimizing membrane microstructure and improving membrane hydrophilicity. A high pure water flux of 173.8L/m 2 h was achieved for the CNCs/CDA blending membrane at 200KPa, which is 24 times that of the CDA membrane (7.2L/m 2 h). The bovine serum albumin (BSA) adsorption amount of the CNCs/CDA blending membrane decreased about 48% compared to that of the CDA membrane. Additionally, the CNCs/CDA blending membrane exhibited better antifouling performance with the flux recovery ratio (FRR) of 89.5% after three fouling cycles, compared to 59.7% for the CDA membrane. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigation of ionizing radiation effect on albumin aqueous solutions

International Nuclear Information System (INIS)

Sizikov, A.M.; Adeeva, L.N.; Ogryzkova, I.F.

1986-01-01

Gamma radiation effect on 0.1-0.5%-albumin aqueous solutions has been investigated; variations of viscosity and optical density of solutions at pH medium different values and completeness of protein separation owing to radiation coagulation have been determined. It is shown that due to radiation coagulation it is possible to quantitatively separate albumin from irradiated aqueous solutions. The albumin coagulation is caused by OH radicals the action of which on albumin macromolecules results in destruction of intramolecular bonds and albumin conformation transformations

Albumin synthesis in protein energy malnutrition

International Nuclear Information System (INIS)

Duggan, C.; Hardy, S.; Kleinman, R.E.; Lembcke, J.; Young, V.E.

1994-01-01

The dietary treatment of protein-energy malnutrition (PEM) has been designed on an empirical basis, with outcomes for successful management including body weight gain and resolution of apathy. We propose using the measurements of protein synthesis as a more objective measure of renourishment. We will therefore randomize a group of malnourished children (weigh-for-height Z score 13 C-leucine and serial measurements of 13 C-enrichment of albumin. Isotope infusions will be performed on days one and three, following a standard three hour fast. Since albumin synthesis is reduced under the influence of cytokines which mediate the inflammatory response, results will be stratified according to the presence or absence of clinically apparent infections. We hypothesize that the provision of added dietary protein will optimize albumin synthesis rates in PEM as well as attenuate the reduction in albumin synthesis seen in the presence of infections. (author). 20 refs

21 CFR 866.5040 - Albumin immunological test system.

Science.gov (United States)

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 of...

Serum albumin--a non-saturable carrier

DEFF Research Database (Denmark)

Brodersen, R; Honoré, B; Larsen, F G

1984-01-01

The shape of binding isotherms for sixteen ligands to human serum albumin showed no signs of approaching saturation at high ligand concentrations. It is suggested that ligand binding to serum albumin is essentially different from saturable binding of substrates to enzymes, of oxygen to haemoglobi...

Bidirectional peritoneal transport of albumin in continuous ambulatory peritoneal dialysis

DEFF Research Database (Denmark)

Joffe, P; Henriksen, Jens Henrik Sahl

1995-01-01

The present study was undertaken in order to assess bidirectional peritoneal kinetics of albumin after simultaneous i.v. and i.p. injection of radioiodinated albumin tracers (125I-RISA and 131I-RISA) in eight clinically stable uraemic patients undergoing continuous ambulatory peritoneal dialysis...... (CAPD). The plasma volume, intravascular albumin mass (IVM), and overall extravasation rate of albumin were not significantly different from that found in healthy controls. Albumin flux from the plasma into the peritoneal cavity was 3.71 +/- 0.82 (SD) mumol/h, which was only 3% of the overall...... extravasation rate (137 +/- 52 mumol/h). Albumin flux from the peritoneal cavity into the plasma was substantially lower (0.22 +/- 0.07 mumol/h, P peritoneal accumulation of the albumin from plasma over 4 h was 14 +/- 3.2 mumol, which was significantly lower than the intraperitoneal albumin...

Amadori albumin in diabetic nephropathy

Directory of Open Access Journals (Sweden)

Km. Neelofar

2015-01-01

Full Text Available 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

A low-protein diet restricts albumin synthesis in nephrotic rats.

OpenAIRE

Kaysen, G A; Jones, H; Martin, V; Hutchison, F N

1989-01-01

High-protein diets increase albumin synthesis in rats with Heymann nephritis but albuminuria increases also, causing serum albumin concentration to be suppressed further than in nephrotic animals eating a low-protein diet. Experiments were designed to determine whether dietary protein augmentation directly stimulates albumin synthesis, or whether instead increased albumin synthesis is triggered by the decrease in serum albumin concentration. Evidence is presented that dietary protein augmenta...

Bacillus anthracis-derived edema toxin (ET counter-regulates movement of neutrophils and macromolecules through the endothelial paracellular pathway

Directory of Open Access Journals (Sweden)

Nguyen Chinh

2012-01-01

Full Text Available Abstract Background A common finding amongst patients with inhalational anthrax is a paucity of polymorphonuclear leukocytes (PMNs in infected tissues in the face of abundant circulating PMNs. A major virulence determinant of anthrax is edema toxin (ET, which is formed by the combination of two proteins produced by the organism, edema factor (EF, which is an adenyl cyclase, and protective antigen (PA. Since cAMP, a product of adenyl cyclase, is known to enhance endothelial barrier integrity, we asked whether ET might decrease extravasation of PMNs into tissues through closure of the paracellular pathway through which PMNs traverse. Results Pretreatment of human microvascular endothelial cell(ECs of the lung (HMVEC-L with ET decreased interleukin (IL-8-driven transendothelial migration (TEM of PMNs with a maximal reduction of nearly 60%. This effect required the presence of both EF and PA. Conversely, ET did not diminish PMN chemotaxis in an EC-free system. Pretreatment of subconfluent HMVEC-Ls decreased transendothelial 14 C-albumin flux by ~ 50% compared to medium controls. Coadministration of ET with either tumor necrosis factor-α or bacterial lipopolysaccharide, each at 100 ng/mL, attenuated the increase of transendothelial 14 C-albumin flux caused by either agent alone. The inhibitory effect of ET on TEM paralleled increases in protein kinase A (PKA activity, but could not be blocked by inhibition of PKA with either H-89 or KT-5720. Finally, we were unable to replicate the ET effect with either forskolin or 3-isobutyl-1-methylxanthine, two agents known to increase cAMP. Conclusions We conclude that ET decreases IL-8-driven TEM of PMNs across HMVEC-L monolayers independent of cAMP/PKA activity.

Adherence of platelets to in situ albumin-binding surfaces under flow conditions: role of surface-adsorbed albumin

International Nuclear Information System (INIS)

Guha Thakurta, Sanjukta; Miller, Robert; Subramanian, Anuradha

2012-01-01

Surfaces that preferentially bind human serum albumin (HSA) were generated by grafting albumin-binding linear peptide (LP1) onto silicon surfaces. The research aim was to evaluate the adsorption pattern of proteins and the adhesion of platelets from platelet-poor plasma and platelet-rich plasma, respectively, by albumin-binding surfaces under physiological shear rate (96 and 319 s −1 ) conditions. Bound proteins were quantified using enzyme-linked immunosorbent assays (ELISAs) and two-dimensional gel electrophoresis. A ratio of ∼1000:100:1 of adsorbed HSA, human immunoglobulin (HIgG) and human fibrinogen (HFib) was noted, respectively, on LP1-functionalized surfaces, and a ratio of ∼5:2:1 of the same was noted on control surfaces, as confirmed by ELISAs. The surface-adsorbed von Willebrand factor was undetectable by sensitive ELISAs. The amount of adhered platelets correlated with the ratio of adsorbed HSA/HFib. Platelet morphology was more rounded on LP1-functionalized surfaces when compared to control surfaces. The platelet adhesion response on albumin-binding surfaces can be explained by the reduction in the co-adsorption of other plasma proteins in a surface environment where there is an excess of albumin molecules, coupled with restrictions in the conformational transitions of other surface-adsorbed proteins into hemostatically active forms. (paper)

Quantitative determination of albumin in microlitre amounts of rat serum: With a short note on serum albumin levels in ageing rats

NARCIS (Netherlands)

Leeuw-Israel, F.R. de; Arp-Neefjes, J.M.; Hollander, C.F.

1967-01-01

A simple dye binding method for determining rat serum albumin, which employs the anionic dye 2-(4′-hydroxybenzneeazo) benzoic acid (HBABA) is described. Albumin in 5μ1 of serum is determined colorimetrically. Purified rat albumin is used as a primary standard and rat serum as a reference sample.

Interaction of amphiphilic drugs with human and bovine serum albumins.

Science.gov (United States)

Khan, Abbul Bashar; Khan, Javed Masood; Ali, Mohd Sajid; Khan, Rizwan Hasan; Kabir-Ud-Din

2012-11-01

To know the interaction of amphiphilic drugs nortriptyline hydrochloride (NOT) and promazine hydrochloride (PMZ) with serum albumins (i.e., human serum albumin (HSA) and bovine serum albumin (BSA)), techniques of UV-visible, fluorescence, and circular dichroism (CD) spectroscopies are used. The binding affinity is more in case of PMZ with both the serum albumins. The quenching rate constant (k(q)) values suggest a static quenching process for all the drug-serum albumin interactions. The UV-visible results show that the change in protein conformation of PMZ-serum albumin interactions are more prominent as compared to NOT-serum albumin interactions. The CD results also explain the conformational changes in the serum albumins on binding with the drugs. The increment in %α-helical structure is slightly more for drug-BSA complexes as compared to drug-HSA complexes. Copyright © 2012 Elsevier B.V. All rights reserved.

Glycated albumin: from biochemistry and laboratory medicine to clinical practice.

Science.gov (United States)

Dozio, Elena; Di Gaetano, Nicola; Findeisen, Peter; Corsi Romanelli, Massimiliano Marco

2017-03-01

This review summarizes current knowledge about glycated albumin. We review the changes induced by glycation on the properties of albumin, the pathological implications of high glycated albumin levels, glycated albumin quantification methods, and the use of glycated albumin as a complementary biomarker for diabetes mellitus diagnosis and monitoring and for dealing with long-term complications. The advantages and limits of this biomarker in different clinical settings are also discussed.

A structurally driven analysis of thiol reactivity in mammalian albumins.

Science.gov (United States)

Spiga, Ottavia; Summa, Domenico; Cirri, Simone; Bernini, Andrea; Venditti, Vincenzo; De Chiara, Matteo; Priora, Raffaella; Frosali, Simona; Margaritis, Antonios; Di Giuseppe, Danila; Di Simplicio, Paolo; Niccolai, Neri

2011-04-01

Understanding the structural basis of protein redox activity is still an open question. Hence, by using a structural genomics approach, different albumins have been chosen to correlate protein structural features with the corresponding reaction rates of thiol exchange between albumin and disulfide DTNB. Predicted structures of rat, porcine, and bovine albumins have been compared with the experimentally derived human albumin. High structural similarity among these four albumins can be observed, in spite of their markedly different reactivity with DTNB. Sequence alignments offered preliminary hints on the contributions of sequence-specific local environments modulating albumin reactivity. Molecular dynamics simulations performed on experimental and predicted albumin structures reveal that thiolation rates are influenced by hydrogen bonding pattern and stability of the acceptor C34 sulphur atom with donor groups of nearby residues. Atom depth evolution of albumin C34 thiol groups has been monitored during Molecular Dynamic trajectories. The most reactive albumins appeared also the ones presenting the C34 sulphur atom on the protein surface with the highest accessibility. High C34 sulphur atom reactivity in rat and porcine albumins seems to be determined by the presence of additional positively charged amino acid residues favoring both the C34 S⁻ form and the approach of DTNB. Copyright © 2011 Wiley Periodicals, Inc.

In-gel detection of esterase-like albumin activity: Characterization of esterase-free sera albumin and its putative role as non-invasive biomarker of hepatic fibrosis

Directory of Open Access Journals (Sweden)

Areeba Ahmad

2017-07-01

Full Text Available Albumin is a globular and un-glycosylated multifunctional plasma protein and thus correlated with several human diseases. Owing to esterase contamination, albumin levels are usually misleading. In this study, we propose methodical accuracy for albumin estimation taking healthy and fibrotic rats. Liver fibrosis in rats was generated by N′-Nitrosodimethylamine (NDMA (10 mg/kg body weight within three weeks followed by its confirmation through H&E and immunohistochemical staining for α-SMA expression. Animal sera were screened by native polyacrylamide gel electrophoresis (native-PAGE (7.5%. In-gel esterase-like albumin activity was detected using α- and β-naphthyl acetate (5.58 × 10−3 mM; pH 7.5 as substrate. Sera albumin was purified from unstained PA gel-slices through electroelution. Subsequent to conformation of albumin purity by its molecular weight determination using SDS–PAGE (10% and peptide mass fingerprinting by MALDI-TOF-MS, samples were treated with different concentrations of urea. Urea-treated albumins were screened for esterase activity, conformational change and, albumin levels by immunoblotting. Our results demonstrate that esterase-like albumin activity in rat sera albumin is located in domain-III. The esterase-like activity remains detectable up to 4 M urea, which diminishes with increasing urea concentrations. Further, immunoblotting of urea-treated albumin samples displays a significant decline in purified protein bands, indicating hypoalbuminemia during hepatic fibrosis in rats. In conclusion, the present approach of albumin separation and estimation is of potential interest and may be recommended for diagnostic purposes.

Generation of Urinary Albumin Fragments Does Not Require Proximal Tubular Uptake

OpenAIRE

Weyer, K.; Nielsen, R.; Christensen, E. I.; Birn, H.

2012-01-01

Urinary albumin excretion is an important diagnostic and prognostic marker of renal function. Both animal and human urine contain large amounts of albumin fragments, but whether these fragments originate from renal tubular degradation of filtered albumin is unknown. Here, we used mice with kidneys lacking megalin and cubilin, the coreceptors that mediate proximal tubular endocytosis of albumin, to determine whether proximal tubular degradation of albumin forms the detectable urinary albumin f...

Albumin grafting on biomaterial surfaces using gamma-irradiation

International Nuclear Information System (INIS)

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

Lipopolysaccharide-induced blood-brain barrier disruption: roles of cyclooxygenase, oxidative stress, neuroinflammation, and elements of the neurovascular unit.

Science.gov (United States)

Banks, William A; Gray, Alicia M; Erickson, Michelle A; Salameh, Therese S; Damodarasamy, Mamatha; Sheibani, Nader; Meabon, James S; Wing, Emily E; Morofuji, Yoichi; Cook, David G; Reed, May J

2015-11-25

Disruption of the blood-brain barrier (BBB) occurs in many diseases and is often mediated by inflammatory and neuroimmune mechanisms. Inflammation is well established as a cause of BBB disruption, but many mechanistic questions remain. We used lipopolysaccharide (LPS) to induce inflammation and BBB disruption in mice. BBB disruption was measured using (14)C-sucrose and radioactively labeled albumin. Brain cytokine responses were measured using multiplex technology and dependence on cyclooxygenase (COX) and oxidative stress determined by treatments with indomethacin and N-acetylcysteine. Astrocyte and microglia/macrophage responses were measured using brain immunohistochemistry. In vitro studies used Transwell cultures of primary brain endothelial cells co- or tri-cultured with astrocytes and pericytes to measure effects of LPS on transendothelial electrical resistance (TEER), cellular distribution of tight junction proteins, and permeability to (14)C-sucrose and radioactive albumin. In comparison to LPS-induced weight loss, the BBB was relatively resistant to LPS-induced disruption. Disruption occurred only with the highest dose of LPS and was most evident in the frontal cortex, thalamus, pons-medulla, and cerebellum with no disruption in the hypothalamus. The in vitro and in vivo patterns of LPS-induced disruption as measured with (14)C-sucrose, radioactive albumin, and TEER suggested involvement of both paracellular and transcytotic pathways. Disruption as measured with albumin and (14)C-sucrose, but not TEER, was blocked by indomethacin. N-acetylcysteine did not affect disruption. In vivo, the measures of neuroinflammation induced by LPS were mainly not reversed by indomethacin. In vitro, the effects on LPS and indomethacin were not altered when brain endothelial cells (BECs) were cultured with astrocytes or pericytes. The BBB is relatively resistant to LPS-induced disruption with some brain regions more vulnerable than others. LPS-induced disruption appears is

Soluble CD40 ligand directly alters glomerular permeability and may act as a circulating permeability factor in FSGS.

Science.gov (United States)

Doublier, Sophie; Zennaro, Cristina; Musante, Luca; Spatola, Tiziana; Candiano, Giovanni; Bruschi, Maurizio; Besso, Luca; Cedrino, Massimo; Carraro, Michele; Ghiggeri, Gian Marco; Camussi, Giovanni; Lupia, Enrico

2017-01-01

CD40/CD40 ligand (CD40L) dyad, a co-stimulatory bi-molecular complex involved in the adaptive immune response, has also potent pro-inflammatory actions in haematopoietic and non-haematopoietic cells. We describe here a novel role for soluble CD40L (sCD40L) as modifier of glomerular permselectivity directly acting on glomerular epithelial cells (GECs). We found that stimulation of CD40, constitutively expressed on GEC cell membrane, by the sCD40L rapidly induced redistribution and loss of nephrin in GECs, and increased albumin permeability in isolated rat glomeruli. Pre-treatment with inhibitors of CD40-CD40L interaction completely prevented these effects. Furthermore, in vivo injection of sCD40L induced a significant reduction of nephrin and podocin expression in mouse glomeruli, although no significant increase of urine protein/creatinine ratio was observed after in vivo injection. The same effects were induced by plasma factors partially purified from post-transplant plasma exchange eluates of patients with focal segmental glomerulosclerosis (FSGS), and were blocked by CD40-CD40L inhibitors. Moreover, 17 and 34 kDa sCD40L isoforms were detected in the same plasmapheresis eluates by Western blotting. Finally, the levels of sCD40Lwere significantly increased in serum of children both with steroid-sensitive and steroid-resistant nephrotic syndrome (NS), and in adult patients with biopsy-proven FSGS, compared to healthy subjects, but neither in children with congenital NS nor in patients with membranous nephropathy. Our results demonstrate that sCD40L directly modifies nephrin and podocin distribution in GECs. Moreover, they suggest that sCD40L contained in plasmapheresis eluates from FSGS patients with post-transplant recurrence may contribute, presumably cooperating with other mediators, to FSGS pathogenesis by modulating glomerular permeability.

Soluble CD40 ligand directly alters glomerular permeability and may act as a circulating permeability factor in FSGS.

Directory of Open Access Journals (Sweden)

Sophie Doublier

Full Text Available CD40/CD40 ligand (CD40L dyad, a co-stimulatory bi-molecular complex involved in the adaptive immune response, has also potent pro-inflammatory actions in haematopoietic and non-haematopoietic cells. We describe here a novel role for soluble CD40L (sCD40L as modifier of glomerular permselectivity directly acting on glomerular epithelial cells (GECs. We found that stimulation of CD40, constitutively expressed on GEC cell membrane, by the sCD40L rapidly induced redistribution and loss of nephrin in GECs, and increased albumin permeability in isolated rat glomeruli. Pre-treatment with inhibitors of CD40-CD40L interaction completely prevented these effects. Furthermore, in vivo injection of sCD40L induced a significant reduction of nephrin and podocin expression in mouse glomeruli, although no significant increase of urine protein/creatinine ratio was observed after in vivo injection. The same effects were induced by plasma factors partially purified from post-transplant plasma exchange eluates of patients with focal segmental glomerulosclerosis (FSGS, and were blocked by CD40-CD40L inhibitors. Moreover, 17 and 34 kDa sCD40L isoforms were detected in the same plasmapheresis eluates by Western blotting. Finally, the levels of sCD40Lwere significantly increased in serum of children both with steroid-sensitive and steroid-resistant nephrotic syndrome (NS, and in adult patients with biopsy-proven FSGS, compared to healthy subjects, but neither in children with congenital NS nor in patients with membranous nephropathy. Our results demonstrate that sCD40L directly modifies nephrin and podocin distribution in GECs. Moreover, they suggest that sCD40L contained in plasmapheresis eluates from FSGS patients with post-transplant recurrence may contribute, presumably cooperating with other mediators, to FSGS pathogenesis by modulating glomerular permeability.

Preparation of S-sulfo albumin film and its cell adhesive property

International Nuclear Information System (INIS)

Yamazoe, Hironori; Yamauchi, Kiyoshi; Tanabe, Toshizumi

2009-01-01

Recently, large-scale production of the pharmaceutical grade recombinant human serum albumin was achieved, and several clinical trials have proved its safety and efficacy. Albumin is thought to be a candidate for a safe biopolymer sources for application to biomaterials. In this study, we treated albumin with sodium sulfite and sodium tetrathionate to give S-sulfo albumin, which was found to loose native albumin structure by CD spectra analysis and dye-binding assay. A water-insoluble S-sulfo albumin films were prepared by drying S-sulfo albumin solution and subsequent reformation of disulfide bonds by the oxidation with iodine. Ultimate strength, ultimate elongation and Young's modulus of S-sulfo albumin film prepared at room temperature were 3.3 ± 0.4 MPa, 30.8 ± 3.2% and 40.8 ± 3.3 MPa before oxidative treatment and changed to 13.8 ± 4.2 MPa, 5.6 ± 2.8% and 401.7 ± 15.3 MPa after oxidative treatment. When the film was prepared at 60 deg. C, similar tendency was observed. Thus, the disulfide bonds formation between albumin molecules by oxidative treatment converted the film stronger and stiffer. Cell adhesion and proliferation on the films were evaluated using mouse L929 fibroblast cells. Cell adhesion largely depended on the albumin structure; that is, cells did not attach to native albumin coated surfaces, while cell adhesion and proliferation occurred on the S-sulfo albumin films which lost their native albumin structure. Eighty percent of seeded cells were adhered on S-sulfo albumin films and proliferated well in a similar manner to those on the conventional culture dish. Our results indicate that S-sulfo albumin is a favorable cell culture substrate.

An albumin-fixed membrane for the removal of protein-bound toxins

International Nuclear Information System (INIS)

Ge Dongtao; Wu Dewang; Shi Wei; Ma Yuanyuan; Tian Xiangdong; Liang Pengfei; Zhang Qiqing

2006-01-01

Established methods for kidney dialysis do not work for liver failure because kidney dialysis removes only water-soluble toxins, while the liver normally removes albumin-bound toxins. In the present study, a polysulfone dialysis membrane with a -OH reactive group was prepared by hydrolyzing the chloromethylated polysulfone membrane, and the bovine serum albumin molecules were fixed into the membrane with 1,1'-carbonyldiimidazole activation. The content of albumin of the albumin-fixed membrane was 121.3 mg (g membrane) -1 . The albumin-fixed dialysis membranes were used to remove protein-bound toxins, bilirubin, from the bilirubin-albumin solution. The transfer rate of bilirubin of the albumin-fixed membrane was obviously higher compared to the normal dialysis membrane. The clearance of bilirubin with the albumin-fixed membrane was 49.8%. The albumin-fixed membrane can easily be regenerated by the bovine serum albumin and NaOH solution. Regeneration of the membrane suggested good mechanical and chemical stability, as well as good clearance of bilirubin. In addition, the effects of membrane thickness and bilirubin initial concentration on the removal of bilirubin were discussed

Transfer of oleic acid between albumin and phospholipid vesicles

International Nuclear Information System (INIS)

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 13 C NMR spectroscopy and 90% isotopically substituted [1- 13 C]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 ≥80% of the oleic acid associated with albumin at pH 7.4; association was ≥90% 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 13 C 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

Albumin-derived peptides efficiently reduce renal uptake of radiolabelled peptides

International Nuclear Information System (INIS)

Vegt, Erik; Eek, Annemarie; Oyen, Wim J.G.; Gotthardt, Martin; Boerman, Otto C.; Jong, Marion de

2010-01-01

In peptide-receptor radionuclide therapy (PRRT), the maximum activity dose that can safely be administered is limited by high renal uptake and retention of radiolabelled peptides. The kidney radiation dose can be reduced by coinfusion of agents that competitively inhibit the reabsorption of radiolabelled peptides, such as positively charged amino acids, Gelofusine, or trypsinised albumin. The aim of this study was to identify more specific and potent inhibitors of the kidney reabsorption of radiolabelled peptides, based on albumin. Albumin was fragmented using cyanogen bromide and six albumin-derived peptides with different numbers of electric charges were selected and synthesised. The effect of albumin fragments (FRALB-C) and selected albumin-derived peptides on the internalisation of 111 In-albumin, 111 In-minigastrin, 111 In-exendin and 111 In-octreotide by megalin-expressing cells was assessed. In rats, the effect of Gelofusine and albumin-derived peptides on the renal uptake and biodistribution of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide was determined. FRALB-C significantly reduced the uptake of all radiolabelled peptides in vitro. The albumin-derived peptides showed different potencies in reducing the uptake of 111 In-albumin, 111 In-exendin and 111 In-minigastrin in vitro. The most efficient albumin-derived peptide (peptide 6), was selected for in vivo testing. In rats, 5 mg of peptide 6 very efficiently inhibited the renal uptake of 111 In-minigastrin, by 88%. Uptake of 111 In-exendin and 111 In-octreotide was reduced by 26 and 33%, respectively. The albumin-derived peptide 6 efficiently inhibited the renal reabsorption of 111 In-minigastrin, 111 In-exendin and 111 In-octreotide and is a promising candidate for kidney protection in PRRT. (orig.)

Electret filter collects more exhaled albumin than glass condenser

Science.gov (United States)

Jia, Ziru; Liu, Hongying; Li, Wang; Xie, Dandan; Cheng, Ke; Pi, Xitian

2018-01-01

Abstract In recent years, noninvasive diagnosis based on biomarkers in exhaled breath has been extensively studied. The procedure of biomarker collection is a key step. However, the traditional condenser method has low efficacy in collecting nonvolatile compounds especially the protein biomarkers in breath. To solve this deficiency, here we propose an electret filter method. Exhaled breath of 6 volunteers was collected with a glass condenser and an electret filter. The amount of albumin was analyzed. Furthermore, the difference of exhaled albumin between smokers and nonsmokers was evaluated. The electret filter method collected more albumin than the glass condenser method at the same breath volume level (P albumin than nonsmokers were also observed (P albumin than nonsmokers. PMID:29384875

Resistance of essential fatty acid-deficient rats to endotoxin-induced increases in vascular permeability

International Nuclear Information System (INIS)

Li, E.J.; Cook, J.A.; Spicer, K.M.; Wise, W.C.; Rokach, J.; Halushka, P.V.

1990-01-01

Resistance to endotoxin in essential fatty acid-deficient (EFAD) rats is associated with reduced synthesis of certain arachidonic acid metabolites. It was hypothesized that EFAD rats would manifest decreased vascular permeability changes during endotoxemia as a consequence of reduced arachidonic acid metabolism. To test this hypothesis, changes in hematocrit (HCT) and mesenteric localization rate of technetium-labeled human serum albumin (99mTc-HSA) and red blood cells (99mTc-RBC) were assessed in EFAD and normal rats using gamma-camera imaging. Thirty minutes after Salmonella enteritidis endotoxin, EFAD rats exhibited less hemoconcentration as determined by % HCT than normal rats. Endotoxin caused a less severe change in permeability index in the splanchnic region in EFAD rats than in normal rats (1.2 +/- 0.6 x 10(-3)min-1 vs. 4.9 +/- 1.7 x 10(-3)min-1 respectively, P less than 0.05). In contrast to 99mTc-HSA, mesenteric localization of 99mTc-RBC was not changed by endotoxin in control or EFAD rats. Supplementation with ethyl-arachidonic acid did not enhance susceptibility of EFAD rats to endotoxin-induced splanchnic permeability to 99mTc-HSA. Leukotrienes have been implicated as mediators of increased vascular permeability in endotoxin shock. Since LTC3 formation has been reported to be increased in EFA deficiency, we hypothesized that LTC3 may be less potent than LTC4. Thus the effect of LTC3 on mean arterial pressure and permeability was compared to LTC4 in normal rats. LTC3-induced increases in peak mean arterial pressure were less than LTC4 at 10 micrograms/kg (39 +/- 5 mm Hg vs. 58 +/- 4 mm Hg respectively, P less than 0.05) and at 20 micrograms/kg (56 +/- 4 mm Hg vs. 75 +/- 2 mm Hg respectively, P less than 0.05). LY171883 (30 mg/kg), an LTD4/E4 receptor antagonist, attenuated the pressor effect of LTC4, LTD4, and LTC3

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

International Nuclear Information System (INIS)

Kumagai, A.K.; Eisenberg, J.B.; Pardridge, W.M.

1987-01-01

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 [ 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 [ 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 [ 3 H]beta-endorphin to unlabeled cationized albumin (pI = 8.5-9) using the bifunctional reagent, N-succinimidyl 3-(2-pyridyldithio)proprionate. The [ 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

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

Energy Technology Data Exchange (ETDEWEB)

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.

Catalase and superoxide dismutase conjugated with platelet-endothelial cell adhesion molecule antibody distinctly alleviate abnormal endothelial permeability caused by exogenous reactive oxygen species and vascular endothelial growth factor.

Science.gov (United States)

Han, Jingyan; Shuvaev, Vladimir V; Muzykantov, Vladimir R

2011-07-01

Reactive oxygen species (ROS) superoxide anion (O(2)()) and hydrogen peroxide (H(2)O(2)) produced by activated leukocytes and endothelial cells in sites of inflammation or ischemia cause endothelial barrier dysfunction that may lead to tissue edema. Antioxidant enzymes (AOEs) catalase and superoxide dismutase (SOD) conjugated with antibodies to platelet-endothelial cell adhesion molecule-1 (PECAM-1) specifically bind to endothelium, quench the corresponding ROS, and alleviate vascular oxidative stress and inflammation. In the present work, we studied the effects of anti-PECAM/catalase and anti-PECAM/SOD conjugates on the abnormal permeability manifested by transendothelial electrical resistance decline, increased fluorescein isothiocyanate-dextran influx, and redistribution of vascular endothelial-cadherin in human umbilical vein endothelial cell (HUVEC) monolayers. Anti-PECAM/catalase protected HUVEC monolayers against H(2)O(2)-induced endothelial barrier dysfunction. Polyethylene glycol-conjugated catalase exerted orders of magnitude lower endothelial uptake and no protective effect, similarly to IgG/catalase. Anti-PECAM/catalase, but not anti-PECAM/SOD, alleviated endothelial hyperpermeability caused by exposure to hypoxanthine/xanthine oxidase, implicating primarily H(2)O(2) in the disruption of the endothelial barrier in this model. Thrombin-induced endothelial permeability was not affected by treatment with anti-PECAM/AOEs or the NADPH oxidase inhibitor apocynin or overexpression of AOEs, indicating that the endogenous ROS play no key role in thrombin-mediated endothelial barrier dysfunction. In contrast, anti-PECAM/SOD, but not anti-PECAM/catalase, inhibited a vascular endothelial growth factor (VEGF)-induced increase in endothelial permeability, identifying a key role of endogenous O(2)() in the VEGF-mediated regulation of endothelial barrier function. Therefore, AOEs targeted to endothelial cells provide versatile molecular tools for testing the roles of

Study of the deuterated albumin by FT-IR spectroscopy

International Nuclear Information System (INIS)

Stoenescu, Daniela; Sahini, V.E.

2000-01-01

The albumin is a protein from the soluble or corpuscular protein class, which exists in cells, in dissolved state or in form of a hydrated gel. Proteins are essential constituents beside water, inorganic salts, lipids, carbon hydrates, vitamins, enzymes. The albumin is also a protein soluble in water and in diluted electrolyte solutions (acids, bases and salts). The investigation of the vibration isotopic effect has a great importance both for the diatomic molecules and for the polyatomic molecules. This paper is the first from a series of works which are intended to study the physico-chemical properties of the deuterated albumin and of the albumin solutions in heavy water by an isotopic exchange method. To put in evidence H-D exchange, the FT-IR spectroscopy is used when the deuterated albumin has different layer thickness. It is also of interest to elucidate the isotopic exchange between the hydrogen and oxygen atoms in bovine serum albumin macromolecules. (authors)

Role of albumin and its modifications in glomerular injury.

Science.gov (United States)

Agrawal, Shipra; Smoyer, William E

2017-08-01

Albuminuria is both a characteristic hallmark and a known risk factor for progressive glomerular disease. Although the molecular basis for a potential causative role for albuminuria in progressive chronic kidney disease remains poorly understood, there have been several recent advances in our understanding of the role of albumin, and its molecular modifications, in the development and progression of glomerular disease. This review discusses recent findings related to the ability of albumin and its associated factors to directly induce podocyte and glomerular injury. Additional recent studies confirming the ability and mechanisms by which podocytes endocytose albumin are also discussed. Lastly, we present several known molecular modifications in the albumin molecule itself, as well as substances bound to it, which may be important and potentially clinically relevant mediators of albumin-induced glomerular injury. These recent findings may create entirely new opportunities to develop novel future therapies directed at albumin that could potentially help reduce podocyte and renal tubular injury and slow the progression of chronic glomerular disease.

The albumin of the brown trout (Salmo trutta) is a glycoprotein.

Science.gov (United States)

Metcalf, V J; Brennan, S O; Chambers, G K; George, P M

1998-07-28

The albumin from an Atlantic salmonid, the brown trout (Salmo trutta), is 1730 Da higher in molecular mass than the albumin from a Pacific salmonid, the chinook salmon (Oncorhynchus tshawytscha), at 65230 Da. Digestion with neuraminidase revealed that purified brown trout albumin contained sialic acid while chinook salmon albumin did not. Concanavalin A-sepharose affinity chromatography was used to purify a glycopeptide from a total tryptic digest of brown trout albumin. The mass of this glycopeptide (3815 Da) was determined by mass spectrometry, and the sequence largely confirmed by N-terminal sequencing. The identified sequence of IAHCCNQSYSM-, contains an Asn-Gln-Ser glycosylation site and is identical to residues 475-485 derived from the cDNA of the albumin from the Atlantic salmon, the closest relative of the brown trout. Glycosylation of albumin is very unusual, and has not been identified in either reptilian or mammalian albumins. The finding of a glycoalbumin in salmonids, ancient members of the teleost fish subclass, coupled with evidence of albumin glycosylation in the oldest vertebrates, agnathans, as well as amphibians, suggests that albumin was originally a glycoprotein, but lost this modification sometime between the divergence of amphibians and reptiles.

Distribution and degradation of albumin in extensive skin disease

DEFF Research Database (Denmark)

Worm, Anne-Marie; Taaning, E; Rossing, N

1981-01-01

The distribution and degradation of albumin were determined in twelve patients with extensive skin disease and in ten control subjects by measuring the metabolic turnover and transcapillary escape of 132 I-labelled albumin. The ratio of intravascular to total mass of albumin was normal. Thus...... the observed hypoalbuminaemia and the low intravascular mass reflect a reduced mass of total body albumin. The rate of synthesis was normal, but the transcapillary escape rate reflecting the microvascular leakiness to macromolecules, and the fractional disappearance rate were significantly higher...

Notional Permeability

NARCIS (Netherlands)

Kik, R.; Van den Bos, J.P.; Maertens, J.; Verhagen, H.J.; Van der Meer, J.W.

2012-01-01

Different layer design of a rock slope and under layers has a large effect on the strengths on the rock slope itself. In the stability formula developed of VAN DER MEER [1988] this effect is represented by the term Notional Permeability with symbol P. A more open, or permeable, structure underneath

High-permeability criterion for BCS classification: segmental/pH dependent permeability considerations.

Science.gov (United States)

Dahan, Arik; Miller, Jonathan M; Hilfinger, John M; Yamashita, Shinji; Yu, Lawrence X; Lennernäs, Hans; Amidon, Gordon L

2010-10-04

The FDA classifies a drug substance as high-permeability when the fraction of dose absorbed (F(abs)) in humans is 90% or higher. This direct correlation between human permeability and F(abs) has been recently controversial, since the β-blocker sotalol showed high F(abs) (90%) and low Caco-2 permeability. The purpose of this study was to investigate the scientific basis for this disparity between permeability and F(abs). The effective permeabilities (P(eff)) of sotalol and metoprolol, a FDA standard for the low/high P(eff) class boundary, were investigated in the rat perfusion model, in three different intestinal segments with pHs corresponding to the physiological pH in each region: (1) proximal jejunum, pH 6.5; (2) mid small intestine, pH 7.0; and (3) distal ileum, pH 7.5. Both metoprolol and sotalol showed pH-dependent permeability, with higher P(eff) at higher pH. At any given pH, sotalol showed lower permeability than metoprolol; however, the permeability of sotalol determined at pH 7.5 exceeded/matched metoprolol's at pH 6.5 and 7.0, respectively. Physicochemical analysis based on ionization, pK(a) and partitioning of these drugs predicted the same trend and clarified the mechanism behind these observed results. Experimental octanol-buffer partitioning experiments confirmed the theoretical curves. An oral dose of metoprolol has been reported to be completely absorbed in the upper small intestine; it follows, hence, that metoprolol's P(eff) value at pH 7.5 is not likely physiologically relevant for an immediate release dosage form, and the permeability at pH 6.5 represents the actual relevant value for the low/high permeability class boundary. Although sotalol's permeability is low at pH 6.5 and 7.0, at pH 7.5 it exceeds/matches the threshold of metoprolol at pH 6.5 and 7.0, most likely responsible for its high F(abs). In conclusion, we have shown that, in fact, there is no discrepancy between P(eff) and F(abs) in sotalol's absorption; the data emphasize that

Albumin Antioxidant Response to Stress in Diabetic Nephropathy Progression

Science.gov (United States)

Medina-Navarro, Rafael; Corona-Candelas, Itzia; Barajas-González, Saúl; Díaz-Flores, Margarita; Durán-Reyes, Genoveva

2014-01-01

Background A new component of the protein antioxidant capacity, designated Response Surplus (RS), was recently described. A major feature of this component is the close relationship between protein antioxidant capacity and molecular structure. Oxidative stress is associated with renal dysfunction in patients with renal failure, and plasma albumin is the target of massive oxidation in nephrotic syndrome and diabetic nephropathy. The aim of the present study was to explore the albumin redox state and the RS component of human albumin isolated from diabetic patients with progressive renal damage. Methods/Principal Findings Serum aliquots were collected and albumin isolated from 125 diabetic patients divided into 5 groups according to their estimated glomerular filtration rate (GFR). In addition to clinical and biochemical variables, the albumin redox state, including antioxidant capacity, thiol group content, and RS component, were evaluated. The albumin antioxidant capacity and thiol group content were reciprocally related to the RS component in association with GFR reduction. The GFR decline and RS component were significantly negatively correlated (R = –0.83, palbumin to stress in relation to the progression of diabetic renal disease was evaluated. The findings confirm that the albumin molecular structure is closely related to its redox state, and is a key factor in the progression of diabetes nephropathy. PMID:25187963

The role of nanoparticles in the albumin-cytarabine and albumin-methotrexate interactions

Energy Technology Data Exchange (ETDEWEB)

Pentak, Danuta, E-mail: danuta.pentak@us.edu.pl [Department of Materials Chemistry and Chemical Technology, Institute of Chemistry, University of Silesia, Szkolna 9, 40-006 Katowice (Poland); Maciążek-Jurczyk, Małgorzata; Zawada, Zygmunt H. [School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Department of Physical Pharmacy, Jagiellońska 4, 41-200 Sosnowiec (Poland)

2017-04-01

Understanding the interactions which occur between nanomaterials and biomolecules is one of the most important issues in nanotechnology. Determining the properties of nanoparticles obtained through the use of novel methods and defining the scope of their application as drug carriers has important practical significance. Nanoparticles containing methotrexate and cytarabine obtained by a modified reverse-phase evaporation method (mREV) were characterized through the use of the UV/Vis and NMR methods. Obtained results confirmed high degree of analysed drugs encapsulation. The encapsulation efficiencies of cytarabine (AraC) and methotrexate (MTX) in L{sub DPPC/AraC/MTX} were found to be 86.30% (AraC) and 86.00% (MTX). The increased permeability of the phospholipid membranes, resulting from physico-chemical properties and the location of the drug, as well as from the physico-chemical properties of the phospholipids themselves, has been confirmed by increase in the length of the T1 relaxation time of protons in the −N{sup +}(CH{sub 3}){sub 3} group. The study of analysed drugs release process from the liposomes has been made for bovine serum albumin, both in the absence (dBSA) and in the presence of fatty acid (BSA). Moreover two types of kinetic models (Bhaskar equation and Rigter-Peppas equation) have been used. Based on the study it has been concluded that mathematical modelling of drug release can be very helpful in speeding up product development and in better understanding the mechanisms controlling drug release from advanced delivery systems. - Graphical abstract: In vitro drug release profiles of different liposomal formulation. - Highlights: • Liposomes containing tested drugs can be obtained by mREV method. • High degree of encapsulation characterizes obtained liposomes. • Cytarabine and methotrexate release from liposomes followed both: diffusion and controlled mechanisms.

Atrial natriuretic peptide (ANP) increases urinary albumin excretion (UAE) in intact and uninephrectomized (UNX) rats

International Nuclear Information System (INIS)

Valentin, J.P.; Ribstein, J.; Mimran, A.

1990-01-01

Previous experimental observations have suggested that ANP increases the transcapillary shift of water and albumin. The present studies were conducted in anesthetized euvolemic rats 6 weeks after UNX or sham operation. The effect of iv infusion of 103-126 hANP was assessed on GFR and ERPF ( 99 Tc.DTPA and 131 I-hippuran clearances), and UAE (nephelemetric method). ANP infusion was associated with no change in mean arterial pressure during the low dose (LD) and a 30 mm Hg decrease during the high dose (HD). ANP induced a dose-dependent and reversible increase in UNaV. Both proximal (as assessed by lithium excretion) and distal reabsorption of sodium were decreased by ANP. GFR was altered whereas ERPF decreased only during HD-AMP; filtration fraction (FF) dose-dependently increased in response to ANP. UAE increased dose-dependently and to a similar extent in both groups in response to ANP. The increase in UAE was readily reversible after discontinuation of ANP. There was a positive correlation between changes in UAE and changes in FF induced by ANP. These results indicate that ANP has a potent albuminuric effect. The simultaneous increase in UAE and FF, which could explain the effect of ANP on proximal tubular handling of sodium, may result from an ANP-induced rise in intraglomerular capillary pressure and/or an increase in glomerular permeability to albumin

Lymphatic albumin clearance from psoriatic skin

International Nuclear Information System (INIS)

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

1983-01-01

In nine patients with untreated psoriasis vulgaris, human serum albumin labelled with 125 I or 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

A modified RIA for minute albumin in human urine

International Nuclear Information System (INIS)

Chen Panzao; Hao Xiuhua; Xiao Shuqing; Li Zhenjia

1989-01-01

A modified radioimmunoassay for minute albuminuria using a solid phase radioiodination technique (Iodogen), and a precipitating reagent (PR) separation was described. The results of RIA and EIA of albumin are compared with each other (r = 0.925). Aliquots of 100μl diluted urine (1:20-1:100) are incubated at 4 deg C overnight with 100μl 125 I-labelled albumin and 100μl antiserum. Separation with 500 μl PR is very successful. The concentration of standard albumin ranges from 50 to 3200 ng/ml. The sensitivity of detection is 5 ng of albumin. The coefficients of inter-assay and intr-assay variation are 3.2-8.2% and 13.0-14.5% respectively. In 70 normal individuals the range of urinary albumin is 1.2-17.8 mg/24h

Evaluation of measures of urinary albumin excretion

NARCIS (Netherlands)

Gansevoort, Ronald T.; Brinkman, Jacoline; Bakker, Stephan J. L.; De Jong, Paul E.; de Zeeuw, Dick

2006-01-01

Albuminuria has recently drawn much attention as a valuable risk marker for cardiovascular and renal disease progression. Albuminuria can be measured and expressed in several ways: 1) in a spot morning urine sample as urinary albumin concentration (mg/liter) or albumin:creatinine ratio (mg/mmol) and

Structural studies on metal-serum albumin. 4

International Nuclear Information System (INIS)

Zhou Yongquia; Hu Xuying; Dou Chao; Liu Hong; Wang Sheyi; Shen Panwen

1992-01-01

There have been no detailed and reliable studies on the environment and configuration of Zn(II), Cd(II) and Hg(II) in the metal centers of human serum albumin and bovine serum albumin to date. In this paper the authentic evidence for the involvement of the cystinyl sulfur atoms in the ligation to the zinc group ions has been obtained from the X-ray photoelectron spectra. To belief that each of the zinc group ions possesses several binding sites in human- and bovine serum albumin and is bound to the deprotonated thiol group (-RS - ) of the cysteinyl residues to form tetrahedral and linear metal centers has been further confirmed by the treatment of ligand to metal charge transfer data with Jorgensen's method. According to these results, it was inferred that these binding sites may be located at the 17 disulfide bridges, most likely at the 7 pairs of adjacent disulfide bridges between positions 75 and 567, in the serum albumin. (author). 42 refs.; 5 figs

Smartphone based point-of-care detector of urine albumin

Science.gov (United States)

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.

Sucrose/bovine serum albumin mediated biomimetic crystallization

Indian Academy of Sciences (India)

To understand the role of the sucrose/bovine serum albumin system in the biomineralization process, we have tested the influence of different concentration of the sucrose/bovine serum albumin (BSA) on calcium carbonate (CaCO3) precipitation. The CaCO3 crystals were characterized by scanning electron microscope ...

Gemcitabine-loaded magnetic albumin nanospheres for cancer chemohyperthermia

International Nuclear Information System (INIS)

Li Hongbo; Ke Fei; An Yanli; Hou Xinxin; Zhang Hao; Lin Mei; Zhang Dongsheng

2013-01-01

Eliminating cancer without harming normal body tissue remains a longstanding challenge in medicine. Toward this goal, we prepared nanosized magnetic albumin nanospheres encapsulating magnetic nanoparticles (Fe 3 O 4 ) and antitumor drugs (Gemcitabine, GEM). Magnetic albumin nanospheres (average size ≈ 224 nm) had good magnetic responsiveness upon exposure to an alternating magnetic field even though Fe 3 O 4 was encased in nanospheres. Thermodynamic test showed that Fe 3 O 4 could serve as a heating source under AMF and lead the nanospheres to reach their steady temperature (45 °C). The release results in vitro indicated that nanospheres had an obvious effect of sustained release of GEM. The result of cytotoxicity assay showed that the toxicity of this material was classified as grade 1, which belongs to no cytotoxicity. The antitumor efficacy of the GEM/Fe 3 O 4 albumin nanospheres combined with magnetic fluid hyperthermia on non-small lung cancer cell line GlC-82 was examined by MTT assay and flow cytometry assay. Compared with nanospheres entrapping GEM group, nanospheres entrapping Fe 3 O 4 combined with MFH group, and GEM/Fe 3 O 4 albumin nanospheres without MFH group, the GEM/Fe 3 O 4 albumin nanospheres exhibited enhanced antitumor efficacy. Thus, the GEM/Fe 3 O 4 albumin nanospheres have promising applications in cancer treatment.

Permeability measuremens of brazilian Eucalyptus

Directory of Open Access Journals (Sweden)

Marcio Rogério da Silva

2010-09-01

Full Text Available The permeability of Brazilian Eucalyptus grandis and Eucalyptus citriodora wood was measured in a custom build gas analysis chamber in order to determine which species could be successfully treated with preservatives. Liquid permeability was tested using an emulsion of Neen oil and a control of distillated water. Air was used to test the gas phase permeability. For both Eucalyptus grandis and Eucalyptus citriodora, the longitudinal permeability of gas was shown to be about twice as great as the liquid phase permeability. No radial permeability was observed for either wood. The permeability of air and water through the sapwood of Eucalyptus grandis was greater than that through the sapwood of Eucalyptus citriodora. The permeability of neen oil preservative through the sapwood of Eucalyptus grandis was also greater than through the sapwood of E. Citradora, but the difference was not statistically significant. Scanning Electron Microscopy images showed that the distribution and obstruction in the vessels could be correlated with observed permeability properties. Irrespective of the causes of differences in permeability between the species, the fluid phase flux through the sapwood of both species was significant, indicating that both Eucalyptus grandis and Eucalyptus citriodora could be successfully treated with wood preservative.

Albumin Dialysis for Liver Failure: A Systematic Review.

Science.gov (United States)

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. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Intestinal Permeability: The Basics

Directory of Open Access Journals (Sweden)

Ingvar Bjarnason

1995-01-01

Full Text Available The authors review some of the more fundamental principles underlying the noninvasive assessment of intestinal permeability in humans, the choice of test markers and their analyses, and the practical aspects of test dose composition and how these can be changed to allow the specific assessment of regional permeability changes and other intestinal functions. The implications of increased intestinal permeability in the pathogenesis of human disease is discussed in relation to findings in patients with Crohn’s disease. A common feature of increased intestinal permeability is the development of a low grade enteropathy, and while quantitatively similar changes may be found in Crohn’s disease these seem to predict relapse of disease. Moreover, factors associated with relapse of Crohn’s disease have in common an action to increase intestinal permeability. While increased intestinal permeability does not seem to be important in the etiology of Crohn’s disease it may be a central mechanism in the clinical relapse of disease.

Effects of ethanol and hyperosmotic perfusates on albumin synthesis and release

International Nuclear Information System (INIS)

Rothschild, M.A.; Oratz, M.; Schreiber, S.S.; Mongelli, J.

1986-01-01

Sucrose and ethanol inhibit albumin synthesis; sucrose via an osmotic mechanism and ethanol during its metabolism. The present study was undertaken to compare the effects of both of these agents on albumin synthesis and secretion, and to see if ethanol inhibition could be related to an osmotic effect. Male, fed rabbits served as liver donors in all studies. There were a total of 35 studies: 13 control; 10 ethanol (39 to 52 mM); 4 cycloheximide (0.5 mM), and 8 sucrose (1%). Plasma volume was measured with 125 I-albumin (human) and extracellular volume measured with either /sup 99m/Tc diethylenetriamine pentaacetic acid or [ 14 C]sucrose. During perfusion, rabbit albumin content in the perfusate was measured immunologically every 15 to 30 min for 225 min. Interstitial albumin efflux was measured by the rate of appearance in the perfusate of 125 I-albumin given to 10 other rabbits 3 days prior to hepatic removal and perfusion. During the initial 75 min of perfusion, 74% of the in vivo equilibrated exchangeable 125 I-albumin appeared in the perfusate, and during this period the rabbit albumin that entered the perfusate was taken to represent efflux from the interstitial volume plus synthesis. Rabbit albumin appearing in the perfusate during the later period of 150 min was taken to represent mainly synthesis and was used to calculate the amount of albumin that would be synthesized in 75 min. The difference between these two values would be hepatic interstitial albumin appearing in the perfusate

Predictive value of C-reactive protein/albumin ratio in acute pancreatitis.

Science.gov (United States)

Kaplan, Mustafa; Ates, Ihsan; Akpinar, Muhammed Yener; Yuksel, Mahmut; Kuzu, Ufuk Baris; Kacar, Sabite; Coskun, Orhan; Kayacetin, Ertugrul

2017-08-15

Serum C-reactive protein (CRP) increases and albumin decreases in patients with inflammation and infection. However, their role in patients with acute pancreatitis is not clear. The present study was to investigate the predictive significance of the CRP/albumin ratio for the prognosis and mortality in acute pancreatitis patients. This study was performed retrospectively with 192 acute pancreatitis patients between January 2002 and June 2015. Ranson scores, Atlanta classification and CRP/albumin ratios of the patients were calculated. The CRP/albumin ratio was higher in deceased patients compared to survivors. The CRP/albumin ratio was positively correlated with Ranson score and Atlanta classification in particular and with important prognostic markers such as hospitalization time, CRP and erythrocyte sedimentation rate. In addition to the CRP/albumin ratio, necrotizing pancreatitis type, moderately severe and severe Atlanta classification, and total Ranson score were independent risk factors of mortality. It was found that an increase of 1 unit in the CRP/albumin ratio resulted in an increase of 1.52 times in mortality risk. A prediction value about CRP/albumin ratio >16.28 was found to be a significant marker in predicting mortality with 92.1% sensitivity and 58.0% specificity. It was seen that Ranson and Atlanta classification were higher in patients with CRP/albumin ratio >16.28 compared with those with CRP/albumin ratio ≤16.28. Patients with CRP/albumin ratio >16.28 had a 19.3 times higher chance of death. The CRP/albumin ratio is a novel but promising, easy-to-measure, repeatable, non-invasive inflammation-based prognostic score in acute pancreatitis. Copyright © 2017 The Editorial Board of Hepatobiliary & Pancreatic Diseases International. Published by Elsevier B.V. All rights reserved.

Extraction and characterization of chickpea (Cicer arietinum) albumin and globulin.

Science.gov (United States)

Liu, L H; Hung, T V; Bennett, L

2008-06-01

Albumin and globulin fractions of 1 Desi and 2 Kabuli varieties of chickpeas (Cicer arietinum) were extracted with water and salt solutions (K(2)SO(4) and NaCl). The extractable yields and particularly the albumin-globulin ratio varied greatly with the extraction medium and chickpea variety. Depending on the procedure employed, albumin could be extracted as a major fraction of chickpea proteins. Higher levels of essential amino acids and sulfur containing amino acids were found in albumins than in globulins of all chickpeas investigated. The common structural characteristics of both Kabuli and Desi chickpea albumins and globulins were clearly identified by densitometric profiles of their sodium dodecyl sulfate polyacrylamide gel patterns. Albumins contained subunits with higher molecular weights than those of globulins. The in vitro digestibility of the chickpea proteins by papain, pepsin, chymotrypsin, and trypsin indicated that globulins were more susceptible to proteolytic hydrolysis.

Impaired Albumin Uptake and Processing Promote Albuminuria in OVE26 Diabetic Mice

Science.gov (United States)

Long, Y. S.; Zheng, S.; Kralik, P. M.; Benz, F. W.

2016-01-01

The importance of proximal tubules dysfunction to diabetic albuminuria is uncertain. OVE26 mice have the most severe albuminuria of all diabetic mouse models but it is not known if impaired tubule uptake and processing are contributing factors. In the current study fluorescent albumin was used to follow the fate of albumin in OVE26 and normal mice. Compared to normal urine, OVE26 urine contained at least 23 times more intact fluorescent albumin but only 3-fold more 70 kD fluorescent dextran. This indicated that a function other than size selective glomerular sieving contributed to OVE26 albuminuria. Imaging of albumin was similar in normal and diabetic tubules for 3 hrs after injection. However 3 days after injection a subset of OVE26 tubules retained strong albumin fluorescence, which was never observed in normal mice. OVE26 tubules with prolonged retention of injected albumin lost the capacity to take up albumin and there was a significant correlation between tubules unable to eliminate fluorescent albumin and total albuminuria. TUNEL staining revealed a 76-fold increase in cell death in OVE26 tubules that retained fluorescent albumin. These results indicate that failure to process and dispose of internalized albumin leads to impaired albumin uptake, increased albuminuria, and tubule cell apoptosis. PMID:27822483

Mena invasive (MenaINV) promotes multicellular streaming motility and transendothelial migration in a mouse model of breast cancer.

Science.gov (United States)

Roussos, Evanthia T; Balsamo, Michele; Alford, Shannon K; Wyckoff, Jeffrey B; Gligorijevic, Bojana; Wang, Yarong; Pozzuto, Maria; Stobezki, Robert; Goswami, Sumanta; Segall, Jeffrey E; Lauffenburger, Douglas A; Bresnick, Anne R; Gertler, Frank B; Condeelis, John S

2011-07-01

We have shown previously that distinct Mena isoforms are expressed in invasive and migratory tumor cells in vivo and that the invasion isoform (Mena(INV)) potentiates carcinoma cell metastasis in murine models of breast cancer. However, the specific step of metastatic progression affected by this isoform and the effects on metastasis of the Mena11a isoform, expressed in primary tumor cells, are largely unknown. Here, we provide evidence that elevated Mena(INV) increases coordinated streaming motility, and enhances transendothelial migration and intravasation of tumor cells. We demonstrate that promotion of these early stages of metastasis by Mena(INV) is dependent on a macrophage-tumor cell paracrine loop. Our studies also show that increased Mena11a expression correlates with decreased expression of colony-stimulating factor 1 and a dramatically decreased ability to participate in paracrine-mediated invasion and intravasation. Our results illustrate the importance of paracrine-mediated cell streaming and intravasation on tumor cell dissemination, and demonstrate that the relative abundance of Mena(INV) and Mena11a helps to regulate these key stages of metastatic progression in breast cancer cells.

Polymerized soluble venom--human serum albumin

International Nuclear Information System (INIS)

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

1985-01-01

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. 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

The CD157-integrin partnership controls transendothelial migration and adhesion of human monocytes.

Science.gov (United States)

Lo Buono, Nicola; Parrotta, Rossella; Morone, Simona; Bovino, Paola; Nacci, Giulia; Ortolan, Erika; Horenstein, Alberto L; Inzhutova, Alona; Ferrero, Enza; Funaro, Ada

2011-05-27

CD157, a member of the CD38 gene family, is an NAD-metabolizing ectoenzyme and a signaling molecule whose role in polarization, migration, and diapedesis of human granulocytes has been documented; however, the molecular events underpinning this role remain to be elucidated. This study focused on the role exerted by CD157 in monocyte migration across the endothelial lining and adhesion to extracellular matrix proteins. The results demonstrated that anti-CD157 antibodies block monocyte transmigration and adhesion to fibronectin and fibrinogen but that CD157 cross-linking is sufficient to overcome the block, suggesting an active signaling role for the molecule. Consistent with this is the observation that CD157 is prevalently located within the detergent-resistant membrane microdomains to which, upon clustering, it promotes the recruitment of β(1) and β(2) integrin, which, in turn, leads to the formation of a multimolecular complex favoring signal transduction. This functional cross-talk with integrins allows CD157 to act as a receptor despite its intrinsic structural inability to do so on its own. Intracellular signals mediated by CD157 rely on the integrin/Src/FAK (focal adhesion kinase) pathway, resulting in increased activity of the MAPK/ERK1/2 and the PI3K/Akt downstream signaling pathways, which are crucial in the control of monocyte transendothelial migration. Collectively, these findings indicate that CD157 acts as a molecular organizer of signaling-competent membrane microdomains and that it forms part of a larger molecular machine ruled by integrins. The CD157-integrin partnership provides optimal adhesion and transmigration of human monocytes.

Permeability to macromolecular contrast media quantified by dynamic MRI correlates with tumor tissue assays of vascular endothelial growth factor (VEGF)

International Nuclear Information System (INIS)

Cyran, Clemens C.; Sennino, Barbara; Fu, Yanjun; Rogut, Victor; Shames, David M.; Chaopathomkul, Bundit; Wendland, Michael F.; McDonald, Donald M.; Brasch, Robert C.; Raatschen, Hans-Juergen

2012-01-01

Purpose: To correlate dynamic MRI assays of macromolecular endothelial permeability with microscopic area–density measurements of vascular endothelial growth factor (VEGF) in tumors. Methods and material: This study compared tumor xenografts from two different human cancer cell lines, MDA-MB-231 tumors (n = 5), and MDA-MB-435 (n = 8), reported to express respectively higher and lower levels of VEGF. Dynamic MRI was enhanced by a prototype macromolecular contrast medium (MMCM), albumin-(Gd-DTPA)35. Quantitative estimates of tumor microvascular permeability (K PS ; μl/min × 100 cm 3 ), obtained using a two-compartment kinetic model, were correlated with immunohistochemical measurements of VEGF in each tumor. Results: Mean K PS was 2.4 times greater in MDA-MB-231 tumors (K PS = 58 ± 30.9 μl/min × 100 cm 3 ) than in MDA-MB-435 tumors (K PS = 24 ± 8.4 μl/min × 100 cm 3 ) (p < 0.05). Correspondingly, the area–density of VEGF in MDA-MB-231 tumors was 2.6 times greater (27.3 ± 2.2%, p < 0.05) than in MDA-MB-435 cancers (10.5 ± 0.5%, p < 0.05). Considering all tumors without regard to cell type, a significant positive correlation (r = 0.67, p < 0.05) was observed between MRI-estimated endothelial permeability and VEGF immunoreactivity. Conclusion: Correlation of MRI assays of endothelial permeability to a MMCM and VEGF immunoreactivity of tumors support the hypothesis that VEGF is a major contributor to increased macromolecular permeability in cancers. When applied clinically, the MMCM-enhanced MRI approach could help to optimize the appropriate application of VEGF-inhibiting therapy on an individual patient basis.

Albumin adsorption onto surfaces of urine collection and analysis containers.

Science.gov (United States)

Robinson, Mary K; Caudill, Samuel P; Koch, David D; Ritchie, James; Hortin, Glen; Eckfeldt, John H; Sandberg, Sverre; Williams, Desmond; Myers, Gary; Miller, W Greg

2014-04-20

Adsorption of albumin onto urine collection and analysis containers may cause falsely low concentrations. We added (125)I-labeled human serum albumin to urine and to phosphate buffered solutions, incubated them with 22 plastic container materials and measured adsorption by liquid scintillation counting. Adsorption of urine albumin (UA) at 5-6 mg/l was containers, and to instrument sample cups and showed <1% change in concentration at 5 mg/l and <0.5% change at 20 mg/l or higher concentrations. Adsorption of albumin from phosphate buffered solutions (2-28%) was larger than that from urine. Albumin adsorption differed among urine samples and plastic materials, but the total influence of adsorption was <1% for all materials and urine samples tested. Adsorption of albumin from phosphate buffered solutions was larger than that from urine and could be a limitation for preparations used as calibrators. Copyright © 2014 Elsevier B.V. All rights reserved.

Interaction of Citrinin with Human Serum Albumin

Directory of Open Access Journals (Sweden)

Miklós Poór

2015-12-01

Full Text Available 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.

Bioactive albumin-based carriers for tumour chemotherapy.

Science.gov (United States)

Shahzad, Yasser; Khan, Ikram Ullah; Hussain, Talib; Alamgeer; Serra, Christophe A; Rizvi, Syed A A; Gerber, Minja; du Plessis, Jeanetta

2014-01-01

Proteins are posed as the natural counterpart of the synthetic polymers for the development of drug delivery systems and few of them, have been regarded safe for drug delivery purposes by the United States Food and Drug Administration (FDA). Serum albumin is the most abundant protein in human blood. Interest in the exploration of pharmaceutical applications of albumin-based drug delivery carriers, especially for the delivery of chemotherapeutic agents, has increased in recent years. Albumin has several advantages over synthetic polymers, as it is biocompatible, biodegradable, has low cytotoxicity and has an excellent binding capacity with various drugs. Micro- and nano-carriers not only protect active pharmaceutical ingredients against degradation, but also offer a prolonged release of drugs in a controlled fashion. Since existing tumour chemotherapeutic agents neither target tumour cells, nor are they specific to tumour cells, a slow release of drugs from carriers would be beneficial in targeting carcinogenic cells intracellularly. This article aims at providing an overview of pharmaceutical applications of albumin as a drug delivery carrier in tumour chemotherapy.

Albumin has no role in the uptake of copper by human fibroblasts

International Nuclear Information System (INIS)

McArdle, H.J.; Guthrie, J.R.; Ackland, M.L.; Danks, D.M.

1987-01-01

The mechanism of copper uptake by cells has been the subject of controversy for some time. This paper examines the possibility of a role for albumin in the uptake of copper by fibroblasts. Although the cells could accumulate copper from a copper-albumin complex, there was no evidence for either copper-albumin or albumin receptors on the cell surface. The possibility of a surface exchange mechanism for copper was examined. While copper uptake showed saturation with increasing concentrations of labelled copper-albumin, adding unlabelled copper to the incubation medium did not inhibit uptake. Adding albumin or histidine to the copper-albumin complex resulted in an inhibition of copper uptake. The results can only be explained by the cell taking up free copper from the incubation medium, with the albumin then releasing its copper to maintain the equilibrium between free and bound metal. Since, in vivo there is essentially no free copper in serum, it is concluded that albumin is most unlikely to play a role in the uptake of copper by fibroblasts

Importance of albumin in cross-reactivity among cat, dog and horse allergens.

Science.gov (United States)

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.

Permeability of porour rhyolite

Science.gov (United States)

Cashman, K.; Rust, A.; Wright, H.; Roberge, J.

2003-04-01

The development of permeability in bubble-bearing magmas determines the efficiency of volatile escape during their ascent through volcanic conduits, which, in turn, controls their explosive potential. As permeability requires bubble connectivity, relationships between permeability and porosity in silicic magmas must be controlled by the formation, growth, deformation and coalescence of their constituent bubbles. Although permeability data on porous volcanic pyroclasts are limited, the database can be greatly extended by including data for ceramic and metallic foams1. Several studies indicate that a single number does not adequately describe the permeability of a foam because inertial effects, which predominate at high flow rates, cause deviations from Darcy's law. These studies suggest that permeability is best modeled using the Forschheimer equation to determine both the Darcy permeability (k1) and the non-Darcian (k2) permeability. Importantly, at the high porosities of ceramic foams (75-95%), both k1 and k2 are strongly dependent on pore size and geometry, suggesting that measurement of these parameters provides important information on foam structure. We determined both the connected porosity (by He-pycnometry) and the permeability (k1 and k2) of rhyolitic samples having a wide range in porosity (22-85%) and vesicle textures. In general, these data support previous observations of a power law relationship between connected porosity and Darcy permeability2. In detail, variations in k1 increase at higher porosities. Similarly, k2 generally increases in both mean and standard deviation with increasing porosity. Measurements made on three mutually perpendicular cores from individual pumice clasts suggest that some of the variability can be explained by anisotropy in the vesicle structure. By comparison with ceramic foams, we suggest that the remaining variability results from differences either in average vesicle size or, more likely, in the size of apertures

Polymerized soluble venom--human serum albumin

Energy Technology Data Exchange (ETDEWEB)

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.

alpha-Glucosidase-albumin conjugates: effect of chronic administration in mice

International Nuclear Information System (INIS)

Allen, T.M.; Murray, L.; Bhardwaj, D.; Poznansky, M.J.

1985-01-01

Enzyme albumin conjugates have been proposed as a means of increasing the efficacy of enzyme use in vivo and decreasing immune response to the enzyme. Particulate drug carriers, however, have a pronounced tendency to localize in the mononuclear phagocyte (reticuloendothelial) system. The authors have examined in mice the effect on phagocytic index, tissue distribution and organ size of continued administration of conjugates of alpha-glucosidase with either homologous or heterologous albumin. Mice received 10 X 2-mg injections of bovine serum albumin (BSA) or mouse serum albumin (MSA), either free, polymerized or conjugated with alpha-glucosidase. Experiments involving BSA had to be terminated before the end of the experiment because of anaphylaxis, but these reactions were less severe to the polymerized albumin than to free albumin. Free BSA, BSA polymer and BSA-enzyme conjugates all caused a decrease in phagocytic index after six injections. Mice receiving MSA showed no evidence of anaphylaxis, but mice receiving six or more injections of free MSA, MSA polymer or MSA-enzyme conjugate had significantly decreased phagocytic indices as compared to controls. Phagocytic indices had returned to normal by 7 days after the final injection. Tissue distribution of 125 I-labeled albumin preparations was determined in either naive or chronically injected mice

Circadian variation of urinary albumin excretion in pregnancy

NARCIS (Netherlands)

Douma, C. E.; van der Post, J. A.; van Acker, B. A.; Boer, K.; Koopman, M. G.

1995-01-01

OBJECTIVE: The hypothesis was tested that circadian variations in urinary albumin excretion of pregnant women in the third trimester of normal pregnancy are different from nonpregnant individuals. DESIGN: Circadian variability in urinary albumin excretion was studied both in pregnant women and in

Intestinal permeability study of minoxidil: assessment of minoxidil as a high permeability reference drug for biopharmaceutics classification.

Science.gov (United States)

Ozawa, Makoto; Tsume, Yasuhiro; Zur, Moran; Dahan, Arik; Amidon, Gordon L

2015-01-05

The purpose of this study was to evaluate minoxidil as a high permeability reference drug for Biopharmaceutics Classification System (BCS). The permeability of minoxidil was determined in in situ intestinal perfusion studies in rodents and permeability studies across Caco-2 cell monolayers. The permeability of minoxidil was compared with that of metoprolol, an FDA reference drug for BCS classification. In rat perfusion studies, the permeability of minoxidil was somewhat higher than that of metoprolol in the jejunum, while minoxidil showed lower permeability than metoprolol in the ileum. The permeability of minoxidil was independent of intestinal segment, while the permeability of metoprolol was region-dependent. Similarly, in mouse perfusion study, the jejunal permeability of minoxidil was 2.5-fold higher than that of metoprolol. Minoxidil and metoprolol showed similar permeability in Caco-2 study at apical pH of 6.5 and basolateral pH of 7.4. The permeability of minoxidil was independent of pH, while metoprolol showed pH-dependent transport in Caco-2 study. Minoxidil exhibited similar permeability in the absorptive direction (AP-BL) in comparison with secretory direction (BL-AP), while metoprolol had higher efflux ratio (ER > 2) at apical pH of 6.5 and basolateral pH of 7.4. No concentration-dependent transport was observed for either minoxidil or metoprolol transport in Caco-2 study. Verapamil did not alter the transport of either compounds across Caco-2 cell monolayers. The permeability of minoxidil was independent of both pH and intestinal segment in intestinal perfusion studies and Caco-2 studies. Caco-2 studies also showed no involvement of carrier mediated transport in the absorption process of minoxidil. These results suggest that minoxidil may be an acceptable reference drug for BCS high permeability classification. However, minoxidil exhibited higher jejunal permeability than metoprolol and thus to use minoxidil as a reference drug would raise the

Small-volume resuscitation from hemorrhagic shock with polymerized human serum albumin.

Science.gov (United States)

Messmer, Catalina; Yalcin, Ozlem; Palmer, Andre F; Cabrales, Pedro

2012-10-01

Human serum albumin (HSA) is used as a plasma expander; however, albumin is readily eliminated from the intravascular space. The objective of this study was to establish the effects of various-sized polymerized HSAs (PolyHSAs) during small-volume resuscitation from hemorrhagic shock on systemic parameters, microvascular hemodynamics, and functional capillary density in the hamster window chamber model. Polymerized HSA size was controlled by varying the cross-link density (ie, molar ratio of glutaraldehyde to HSA). Hemorrhage was induced by controlled arterial bleeding of 50% of the animal's blood volume (BV), and hypovolemic shock was maintained for 1 hour. Resuscitation was implemented in 2 phases, first, by infusion of 3.5% of the BV of hypertonic saline (7.5% NaCl) then followed by infusion of 10% of the BV of each PolyHSA. Resuscitation provided rapid recovery of blood pressure, blood gas parameters, and microvascular perfusion. Polymerized HSA at a glutaraldehyde-to-HSA molar ratio of 60:1 (PolyHSA(60:1)) provided superior recovery of blood pressure, microvascular blood flow, and functional capillary density, and acid-base balance, with sustained volume expansion in relation to the volume infused. The high molecular weight of PolyHSA(60:1) increased the hydrodynamic radius and solution viscosity. Pharmacokinetic analysis of PolyHSA(60:1) indicates reduced clearance and increased circulatory half-life compared with monomeric HSA and other PolyHSA formulations. In conclusion, HSA molecular size and solution viscosity affect central hemodynamics, microvascular blood flow, volume expansion, and circulation persistence during small-volume resuscitation from hemorrhagic shock. In addition, PolyHSA can be an alternative to HSA in pathophysiological situations with compromised vascular permeability. Copyright © 2012 Elsevier Inc. All rights reserved.

Interstitial adenosine concentration is increased by dipyridamole

International Nuclear Information System (INIS)

Gorman, M.W.; Wangler, R.D.; DeWitt, D.F.; Wang, C.Y.; Bassingthwaighte, J.B.; Sparks, H.V.

1986-01-01

The authors used the multiple indicator dilution technique to observe the capillary transport of adenosine (ADO) in isolated guinea pig hearts. Radiolabelled albumin, sucrose and ADO were injected on the arterial side and measured in venous samples collected during the following 20 seconds. Transport parameters calculated from these data include permeability-surface area products (PS) for transendothelial diffusion, endothelial cell (EC) uptake at the lumenal and ablumenal membranes, and EC metabolism. With simultaneous measurements of arterial and venous ADO concentrations and flow, the authors calculated the steady-state interstitial fluid (ISF) ADO concentration. Under control conditions the venous ADO concentration was 7.1 +/- 2.8 nM. The calculated ISF concentration depends on whether they assume the venous ADO comes from the ISF, or directly from ECs. These ISF concentrations are 25 +/- 12 nM and 9.8 +/- 4.0 nM, respectively. During dipyridamole infusion (10 uM) the EC transport parameters became nearly zero. Venous and ISF ADO concentrations increased to 33 +/- 8.9 nM and 169 +/- 42 nM, respectively. The authors conclude that the ISF ADO concentration is 1.5-4 fold higher than the venous concentration at rest, and the ISF concentration increases greatly with dipyridamole

Evaluation of use of human albumin in critically ill dogs: 73 cases (2003-2006).

Science.gov (United States)

Trow, Amy V; Rozanski, Elizabeth A; Delaforcade, Armelle M; Chan, Daniel L

2008-08-15

To evaluate the use of human albumin in critically ill dogs. Design-Retrospective case series. 73 client-owned hospitalized dogs. Medical records of dogs that received human albumin were reviewed to assess effects of the use of human albumin on serum albumin concentration, colloid osmotic pressure, and total protein concentration; determine the relationships between these variables and outcome; and assess its safety. Data for signalment, diagnoses, physiologic variables, dosage, amount of crystalloid fluid administered prior to human albumin administration, complications, and outcome were reviewed. Additionally, pre- and postadministration values for serum albumin, colloid osmotic pressure, and total protein were recorded. Administration of human albumin resulted in significant changes in serum albumin, colloid osmotic pressure, and total protein. The serum albumin, total protein, degree of improvement in serum albumin, colloid osmotic pressure, and dosage of human albumin were significantly greater in survivors. Seventeen of 73 (23%) dogs had at least 1 complication that could be potentially associated with the administration of human albumin that occurred during or immediately following administration of human albumin. Three of 73 (4%) dogs had severe delayed complications. Administration of human albumin significantly increased serum albumin, and total protein concentrations and colloid osmotic pressure, especially in survivors. Because of the high mortality rate of the study population and other confounding factors, it was uncertain whether complications were associated with the underlying disease or with human albumin administration. Acute and delayed complications may have been under-recognized.

Role played by Disabled-2 in albumin induced MAP Kinase signalling

International Nuclear Information System (INIS)

Diwakar, Ramaswamy; Pearson, Alexander L.; Colville-Nash, Paul; Baines, Deborah L.; Dockrell, Mark E.C.

2008-01-01

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 TGFβ-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 TGFβ-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 TGFβ-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

Investigation of the influence of ionizing radiation on aqueous solutions of albumin

International Nuclear Information System (INIS)

Sizikov, A.M.; Adeeva, L.N.; Ogryzkova, I.F.

1986-01-01

It was shown that as a result of radiation coagulation, a quantitative isolation of albumin from irradiated aqueous solutions is possible. The coagulation of albumin is induced by OH radicals, the action of which on the albumin macromolecules leads to a breakdown of intramolecular bonds and to conformational conversions of albumin

Albumin levels and cause-specific mortality in community-dwelling older adults.

Science.gov (United States)

Wu, Chen-Yi; Hu, Hsiao-Yun; Huang, Nicole; Chou, Yi-Chang; Li, Chung-Pin; Chou, Yiing-Jenq

2018-04-09

To investigate the association between serum albumin levels and cause-specific mortality among community-dwelling older adults. This cohort study was based on data obtained from the government-sponsored Annual Geriatric Health Examination Program for the older adults in Taipei City between 2006 and 2010. The study sample consisted of 77,531 community-dwelling Taipei citizens (≥65 years old). Mortality was determined by matching the participants' medical records with national death files. Serum albumin levels were categorized into dwelling older adults had a mean albumin level of 4.3 g/dL, which significantly reduced by age. Compared to albumin levels ≥4.4 g/dL, mildly low albumin levels (4.2-4.3 g/dL) were associated with an increased mortality risk (hazard ratio [HR]: 1.16, 95% confidence interval [CI]: 1.05-1.28 for all-cause mortality), and albumin levels dwelling older adults, and mortality risk increased as the albumin level decreased. Copyright © 2017. Published by Elsevier Inc.

Biocompatibility of electrospun human albumin: a pilot study.

Science.gov (United States)

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

2015-03-02

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.

Nephroprotective Potential of Human Albumin Infusion: A Narrative Review

OpenAIRE

Christian J. Wiedermann; Michael Joannidis

2015-01-01

Albumin infusion improves renal function in cirrhosis; however, mechanisms are incompletely understood. In clinical practice, human albumin is used in various intensive care unit indications to deal with a wide range of problems, from volume replacement in hypovolemic shock, or sepsis, to treatment of ascites in patients with liver cirrhosis. Against the background of the results of recent studies on the use of human albumin in septic patients, the importance of the natural colloid in these c...

Production of biological nanoparticles from bovine serum albumin ...

African Journals Online (AJOL)

Production of biological nanoparticles from bovine serum albumin for drug delivery. ... Bovine serum albumin (BSA) was used for generation of nanoparticles in a drug delivery system. ... The impact of protein concentration and additional rate of organic solvent (i.e. ethanol) upon the particle ... AJOL African Journals Online.

Real-Time Tracking the Synthesis and Degradation of Albumin in Complex Biological Systems with a near-Infrared Fluorescent Probe.

Science.gov (United States)

Jin, Qiang; Feng, Lei; Zhang, Shui-Jun; Wang, Dan-Dan; Wang, Fang-Jun; Zhang, Yi; Cui, Jing-Nan; Guo, Wen-Zhi; Ge, Guang-Bo; Yang, Ling

2017-09-19

In this study, a novel fluorescent detection system for biological sensing of human albumin (HA) was developed on the basis of the pseudoesterase activity and substrate preference of HA. The designed near-infrared (NIR) fluorescent probe (DDAP) could be effectively hydrolyzed by HA, accompanied by significant changes in both color and fluorescence spectrum. The sensing mechanism was fully investigated by fluorescence spectroscopy, NMR, and mass spectra. DDAP exhibited excellent selectivity and sensitivity toward HA over a variety of human plasma proteins, hydrolases, and abundant biomolecules found in human body. The probe has been successfully applied to measure native HA in diluted plasma samples and the secreted HA in the hepatocyte culture supernatant. DDAP has also been used for fluorescence imaging of HA reabsorption in living renal cells, and the results show that the probe exhibits good cell permeability, low cytotoxicity and high imaging resolution. Furthermore, DDAP has been successfully used for real-time tracking the uptaking and degradation of albumin in ex vivo mouse kidney models for the first time. All these results clearly demonstrated that DDAP-based assay held great promise for real-time sensing and tracking HA in complex biological systems, which would be very useful for basic researches and clinical diagnosis of HA-associated diseases.

Quantification of carbamylated albumin in serum based on capillary electrophoresis.

Science.gov (United States)

Delanghe, Sigurd; Moerman, Alena; Pletinck, Anneleen; Schepers, Eva; Glorieux, Griet; Van Biesen, Wim; Delanghe, Joris R; Speeckaert, Marijn M

2017-09-01

Protein carbamylation, a nonenzymatic posttranslational modification promoted during uremia, is linked to a poor prognosis. In the present study, carbamylation of serum albumin was assayed using the symmetry factor on a capillary electrophoresis instrument (Helena V8). The symmetry factor has been defined as the distance from the center line of the peak to the back slope, divided by the distance from the center line of the peak to the front slope, with all measurements made at 10% of the maximum peak height. Serum albumin, creatinine, and urea concentrations were assayed using routine methods, whereas uremic toxins were determined using HPLC. In vitro carbamylation induced a marked albumin peak asymmetry. Reference values for the albumin symmetry factor were 0.69-0.92. In kidney patients, albumin peak asymmetry corresponded to the chronic kidney disease stage (p < 0.0001). The symmetry factor correlated well with serum urea (r = -0.5595, p < 0.0001) and creatinine (r = -0.5986, p < 0.0001) concentrations. Several protein-bound uremic toxins showed a significant negative correlation with the symmetry factor. Morphology of the albumin fraction was not affected by presence of glycated albumin and protein-bound antibiotics. In conclusion, the presented method provides a simple, practical way for monitoring protein carbamylation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Functional and rheological properties of amaranth albumins extracted from two Mexican varieties.

Science.gov (United States)

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.

Heterogeneity of brain blood flow and permeability during acute hypertension

International Nuclear Information System (INIS)

Baumbach, G.L.; Heistad, D.D.

1985-01-01

The purpose of this study was to examine regional autoregulation of blood flow in the brain during acute hypertension. In anesthetized cats severe hypertension increased blood flow more in cerebrum (159%) and cerebellum (106%) than brain stem (58%). In contrast to the heterogeneous autoregulatory response, hypocapnia produced uniform vasoconstriction in the brain. The authors also compared vasodilatation during severe hypertension with vasodilatation during hypercapnia. During hypercapnia, blood flow increased as much in brain stem, as in cerebrum and cerebellum. Thus, regional differences in autoregulation appear to be specific for autoregulatory stimulus and are not secondary to nonspecific differences in vasoconstrictor or vasodilator capacity. To determine whether the blood-brain barrier is more susceptible to hypertensive disruption in regions with less effective autoregulation, permeability of the barrier was quantitated with 125 I-albumin. Severe hypertension produced disruption of the barrier in cerebrum but not in brain stem. Thus, there are parallel differences in effectiveness of autoregulation and susceptibility to disruption of the blood-brain barrier in different regions of the brain

Species Differences in the Binding of Sodium 4-Phenylbutyrate to Serum Albumin.

Science.gov (United States)

Yamasaki, Keishi; Enokida, Taisuke; Taguchi, Kazuaki; Miyamura, Shigeyuki; Kawai, Akito; Miyamoto, Shuichi; Maruyama, Toru; Seo, Hakaru; Otagiri, Masaki

2017-09-01

Sodium 4-phenylbutyrate (PB) is clinically used as a drug for treating urea cycle disorders. Recent research has shown that PB also has other pharmacologic activities, suggesting that it has the potential for use as a drug for treating other disorders. In the process of drug development, preclinical testing using experimental animals is necessary to verify the efficacy and safety of PB. Although the binding of PB to human albumin has been studied, our knowledge of its binding to albumin from the other animal species is extremely limited. To address this issue, we characterized the binding of PB to albumin from several species (human, bovine, rabbit, and rat). The results indicated that PB interacts with 1 high-affinity site of albumin from these species, which corresponds to site II of human albumin. The affinities of PB to human and bovine albumins were higher than those to rabbit and rat albumin, and that to rabbit albumin was the lowest. Binding and molecular docking studies using structurally related compounds of PB suggested that species differences in the affinity are attributed to differences in the structural feature of the PB-binding sites on albumins (e.g., charge distribution, hydrophobicity, shape, or size). Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Effect of glycation of albumin on its renal clearance in normal and diabetic rats

International Nuclear Information System (INIS)

Layton, G.J.; Jerums, G.

1988-01-01

Two independent techniques have been used to study the renal clearances of nonenzymatically glycated albumin and nonglycated albumin in normal and streptozotocin-induced diabetic rats, 16 to 24 weeks after the onset of diabetes. In the first technique, serum and urinary endogenous glycated and nonglycated albumin were separated using m-aminophenylboronate affinity chromatography and subsequently quantified by radioimmunoassay. Endogenous glycated albumin was cleared approximately twofold faster than nonglycated albumin in normal and diabetic rats. However, no difference was observed in the glycated albumin/nonglycated albumin clearance ratios (Cga/Calb) in normal and diabetic rats, respectively (2.18 +/- 0.39 vs 1.83 +/- 0.22, P greater than 0.05). The second technique measured the renal clearance of injected 125I-labelled glycated albumin and 125I-labelled albumin. The endogenous results were supported by the finding that 125I-labelled glycated albumin was cleared more rapidly than 125I-labelled albumin in normal (P less than 0.01) and diabetic (P less than 0.05) rats. The Cga/Calb ratio calculated for the radiolabelled albumins was 1.4 and 2.0 in normal and diabetic rats, respectively. This evidence suggests that nonenzymatic glycation of albumin increases its renal clearance to a similar degree in normal and diabetic rats

Sub-core permeability and relative permeability characterization with Positron Emission Tomography

Science.gov (United States)

Zahasky, C.; Benson, S. M.

2017-12-01

This study utilizes preclinical micro-Positron Emission Tomography (PET) to image and quantify the transport behavior of pulses of a conservative aqueous radiotracer injected during single and multiphase flow experiments in a Berea sandstone core with axial parallel bedding heterogeneity. The core is discretized into streamtubes, and using the micro-PET data, expressions are derived from spatial moment analysis for calculating sub-core scale tracer flux and pore water velocity. Using the flux and velocity data, it is then possible to calculate porosity and saturation from volumetric flux balance, and calculate permeability and water relative permeability from Darcy's law. Full 3D simulations are then constructed based on this core characterization. Simulation results are compared with experimental results in order to test the assumptions of the simple streamtube model. Errors and limitations of this analysis will be discussed. These new methods of imaging and sub-core permeability and relative permeability measurements enable experimental quantification of transport behavior across scales.

The CD157-Integrin Partnership Controls Transendothelial Migration and Adhesion of Human Monocytes*

Science.gov (United States)

Lo Buono, Nicola; Parrotta, Rossella; Morone, Simona; Bovino, Paola; Nacci, Giulia; Ortolan, Erika; Horenstein, Alberto L.; Inzhutova, Alona; Ferrero, Enza; Funaro, Ada

2011-01-01

CD157, a member of the CD38 gene family, is an NAD-metabolizing ectoenzyme and a signaling molecule whose role in polarization, migration, and diapedesis of human granulocytes has been documented; however, the molecular events underpinning this role remain to be elucidated. This study focused on the role exerted by CD157 in monocyte migration across the endothelial lining and adhesion to extracellular matrix proteins. The results demonstrated that anti-CD157 antibodies block monocyte transmigration and adhesion to fibronectin and fibrinogen but that CD157 cross-linking is sufficient to overcome the block, suggesting an active signaling role for the molecule. Consistent with this is the observation that CD157 is prevalently located within the detergent-resistant membrane microdomains to which, upon clustering, it promotes the recruitment of β1 and β2 integrin, which, in turn, leads to the formation of a multimolecular complex favoring signal transduction. This functional cross-talk with integrins allows CD157 to act as a receptor despite its intrinsic structural inability to do so on its own. Intracellular signals mediated by CD157 rely on the integrin/Src/FAK (focal adhesion kinase) pathway, resulting in increased activity of the MAPK/ERK1/2 and the PI3K/Akt downstream signaling pathways, which are crucial in the control of monocyte transendothelial migration. Collectively, these findings indicate that CD157 acts as a molecular organizer of signaling-competent membrane microdomains and that it forms part of a larger molecular machine ruled by integrins. The CD157-integrin partnership provides optimal adhesion and transmigration of human monocytes. PMID:21478153

Microalbuminuria reflects a generalized transvascular albumin leakiness in clinically healthy subjects

DEFF Research Database (Denmark)

Jensen, J S; Borch-Johnsen, K; Jensen, G

1995-01-01

1. In epidemiological studies microalbuminuria, i.e. slightly elevated urinary albumin excretion rate, predicts increased atherosclerotic vascular morbidity and mortality. This study aimed to test the hypothesis that microalbuminuria in clinically healthy subjects is associated with a systemic...... transvascular albumin leakiness. In animal experiments the outflux of albumin and lipids to the arterial wall are highly correlated, and both are elevated in atherosclerosis. 2. All participants were recruited at random from a population-based epidemiological study, where the upper decile of urinary albumin...... excretion rate was 6.6 micrograms/min. Twenty-seven patients with persistent microalbuminuria (urinary albumin excretion rate 6.6-150 micrograms/min), and 56 age- and sex-matched control subjects with persistent normoalbuminuria (UAER

Serum Albumin Is Independently Associated with Persistent Organ Failure in Acute Pancreatitis

Directory of Open Access Journals (Sweden)

Wandong Hong

2017-01-01

Full Text Available Background and Aims. To investigate the association between serum albumin levels within 24 hrs of patient admission and the development of persistent organ failure in acute pancreatitis. Methods. A total of 700 patients with acute pancreatitis were enrolled. Multivariate logistic regression and subgroup analysis determined whether decreased albumin was independently associated with persistent organ failure and mortality. The diagnostic performance of serum albumin was evaluated by the area under Receiver Operating Characteristic (ROC curves. Results. As levels of serum albumin decrease, the risk of persistent organ failure significantly increases (Ptrend<0.001. The incidence of organ failure was 3.5%, 10.6%, and 41.6% in patients with normal albumin and mild and severe hypoalbuminaemia, respectively. Decreased albumin levels were also proportionally associated with prolonged hospital stay (Ptrend<0.001 and the risk of death (Ptrend<0.001. Multivariate analysis suggested that biliary etiology, chronic concomitant diseases, hematocrit, blood urea nitrogen, and the serum albumin level were independently associated with persistent organ failure. Blood urea nitrogen and the serum albumin level were also independently associated with mortality. The area under ROC curves of albumin for predicting organ failure and mortality were 0.78 and 0.87, respectively. Conclusion. A low serum albumin is independently associated with an increased risk of developing of persistent organ failure and death in acute pancreatitis. It may also be useful for the prediction of the severity of acute pancreatitis.

Glycation alters ligand binding, enzymatic, and pharmacological properties of human albumin.

Science.gov (United States)

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.

Permeability prediction in chalks

DEFF Research Database (Denmark)

Alam, Mohammad Monzurul; Fabricius, Ida Lykke; Prasad, Manika

2011-01-01

The velocity of elastic waves is the primary datum available for acquiring information about subsurface characteristics such as lithology and porosity. Cheap and quick (spatial coverage, ease of measurement) information of permeability can be achieved, if sonic velocity is used for permeability p...... significantly using the effective specific surface as the fluid-flow concept. The FZI unit is appropriate for highly permeable sedimentary rocks such as sandstones and limestones that have small surface areas....

Albumin synthesis in protein energy malnutrition

International Nuclear Information System (INIS)

Duggan, C.; Hardy, S.; Kleinman, R.E.; Harvard Medical School, Children's Hospital, Boston, MA; Lembcke, J.; Young, V.R.

1996-01-01

Assessment of protein nutritional status during re-feeding children with protein energy malnutrition (PEM) can be difficult. We hypothesized that the fractional synthesis rate (FSR) of albumin, as measured by stable isotope technology, would serve as an objective measure of changes in protein status, and that increased amounts of dietary protein (15% of calories vs 10%) would lead to higher FSR. Eight (5 M, 3 F) Peruvian children (mean age 15.5 months) with PEM (mean wt/ht Z score = -2.47) were studied twice during the first week of admission by the flooding dose technique. An intravenous dose of 13 C-leucine (57 mg/kg, 99 atom%) was given and serial blood samples were drawn in intervals up to 90 minutes in order to measure isotopic enrichment of serum albumin. Mean FSR for the day one infusion was 6.11% (range 3.07 - 15.37%) (n = 8). Mean FSR for the follow-up infusion was 7.67% (range 3.63 - 12.37%) (n = 5), and FSR was no different between the two dietary groups. FSR on day one was inversely related to age (r = -0.62), and one patient with Shigella dysentery had the highest FSR (15.9%). We conclude that FSR of albumin can be measured successfully in children with PEM using the flooding dose technique, and that assessment of albumin FSR holds promise to help determine protein requirements and status during recovery from PEM. (author). 14 refs, 6 figs, 3 tabs

Albumin synthesis in protein energy malnutrition

Energy Technology Data Exchange (ETDEWEB)

Duggan, C; Hardy, S; Kleinman, R E [Massachusetts General Hospital, Boston, MA (United States); [Harvard Medical School, Children` s Hospital, Boston, MA (United States). Combined Program in Pediatric GI and Nutrition; Lembcke, J [Av. La Universidad S/N - La Molina, Lima (Peru). Inst. de Investigacion Nutricional; Young, V R [Massachussetts Inst. of Technology, Cambridge, MA (United States). Lab. of Human Nutrition

1997-12-31

Assessment of protein nutritional status during re-feeding children with protein energy malnutrition (PEM) can be difficult. We hypothesized that the fractional synthesis rate (FSR) of albumin, as measured by stable isotope technology, would serve as an objective measure of changes in protein status, and that increased amounts of dietary protein (15% of calories vs 10%) would lead to higher FSR. Eight (5 M, 3 F) Peruvian children (mean age 15.5 months) with PEM (mean wt/ht Z score = -2.47) were studied twice during the first week of admission by the flooding dose technique. An intravenous dose of {sup 13}C-leucine (57 mg/kg, 99 atom%) was given and serial blood samples were drawn in intervals up to 90 minutes in order to measure isotopic enrichment of serum albumin. Mean FSR for the day one infusion was 6.11% (range 3.07 - 15.37%) (n = 8). Mean FSR for the follow-up infusion was 7.67% (range 3.63 - 12.37%) (n = 5), and FSR was no different between the two dietary groups. FSR on day one was inversely related to age (r = -0.62), and one patient with Shigella dysentery had the highest FSR (15.9%). We conclude that FSR of albumin can be measured successfully in children with PEM using the flooding dose technique, and that assessment of albumin FSR holds promise to help determine protein requirements and status during recovery from PEM. (author). 14 refs, 6 figs, 3 tabs.

Albumin-mediated delivery of siRNA

DEFF Research Database (Denmark)

Bienk, Konrad

2015-01-01

. The human body, however, possesses several natural transport mechanisms for active transport of molecules. Amongst these is albumin, which is the most abundant plasma protein and has a circulatory half-life of ~21 days, partially due to engagement and recycling by the neonatal Fc receptor (FcRn). Albumin...... vehicle. This proof of concept silencing showed that siRNA can be used for therapeutic purposes without the use of non-biocompatible polymer or lipid materials. This work, therefore, provides a novel technology platform for the safe delivery of siRNA therapeutics....

DEGRADATION AND INTRAHEPATIC COMPATIBILITY OF ALBUMIN-HEPARIN CONJUGATE MICROSPHERES

NARCIS (Netherlands)

CREMERS, HFM; WOLF, RFE; BLAAUW, EH; SCHAKENRAAD, JM; LAM, KH; NIEUWENHUIS, P; VERRIJK, R; KWON, G; BAE, YH; KIM, SW; FEIJEN, J

The in vitro degradation properties of glutaraldehyde cross-linked albumin and albumin-heparin conjugate microspheres (AMS and AHCMS respectively) were evaluated using light microscopy, turbidity measurements and heparin release determinations, showing that the microspheres are degraded by

Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods.

Science.gov (United States)

Li, Hui; Kayhanian, Masoud; Harvey, John T

2013-03-30

Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50-90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability. Copyright © 2013 Elsevier Ltd. All rights reserved.

A comparative study of some physico-chemical properties of human serum albumin samples from different sources--I : Some physico-chemical properties of isoionic human serum albumin solutions

NARCIS (Netherlands)

Dröge, J.H.M.; Janssen, L.H.M.; Wilting, J.

1982-01-01

Human serum albumin samples from different sources were investigated. The fatty acid content of the albumin before and after deionization on a mixed bed ion-exchange column varied from sample to sample. When an albumin sample from one source was deionized under standard conditions the amount of

Relative Permeability of Fractured Rock

Energy Technology Data Exchange (ETDEWEB)

Mark D. Habana

2002-06-30

Contemporary understanding of multiphase flow through fractures is limited. Different studies using synthetic fractures and various fluids have yielded different relative permeability-saturation relations. This study aimed to extend the understanding of multiphase flow by conducting nitrogen-water relative permeability experiments on a naturally-fractured rock from The Geysers geothermal field. The steady-state approach was used. However, steady state was achieved only at the endpoint saturations. Several difficulties were encountered that are attributed to phase interference and changes in fracture aperture and surface roughness, along with fracture propagation/initiation. Absolute permeabilities were determined using nitrogen and water. The permeability values obtained change with the number of load cycles. Determining the absolute permeability of a core is especially important in a fractured rock. The rock may change as asperities are destroyed and fractures propagate or st rain harden as the net stresses vary. Pressure spikes occurred in water a solute permeability experiments. Conceptual models of an elastic fracture network can explain the pressure spike behavior. At the endpoint saturations the water relative permeabilities obtained are much less than the nitrogen gas relative permeabilities. Saturations were determined by weighing and by resistivity calculations. The resistivity-saturation relationship developed for the core gave saturation values that differ by 5% from the value determined by weighing. Further work is required to complete the relative permeability curve. The steady-state experimental approach encountered difficulties due to phase interference and fracture change. Steady state may not be reached until an impractical length of time. Thus, unsteady-state methods should be pursued. In unsteady-state experiments the challenge will be in quantifying rock fracture change in addition to fluid flow changes.

Human Albumin Use in Adults in U.S. Academic Medical Centers.

Science.gov (United States)

Suarez, Jose I; Martin, Renee H; Hohmann, Samuel F; Calvillo, Eusebia; Bershad, Eric M; Venkatasubba Rao, Chethan P; Georgiadis, Alexandros; Flower, Oliver; Zygun, David; Finfer, Simon

2017-01-01

To determine rates and predictors of albumin administration, and estimated costs in hospitalized adults in the United States. Cohort study of adult patients from the University HealthSystem Consortium database from 2009 to 2013. One hundred twenty academic medical centers and 299 affiliated hospitals. A total of 12,366,264 hospitalization records. Analysis of rates and predictors of albumin administration, and estimated costs. Overall the proportion of admissions during which albumin was administered increased from 6.2% in 2009 to 7.5% in 2013; absolute difference 1.3% (95% CI, 1.30-1.40%; p Albumin use varied geographically being lowest with no increase in hospitals in the North Eastern United States (4.9% in 2009 and 5.3% in 2013) and was more common in bigger (> 750 beds; 5.2% in 2009 and 7.3% in 2013) compared to smaller hospitals (albumin use were appropriate indication for albumin use (odds ratio, 65.220; 95% CI, 62.459-68.103); surgical admission (odds ratio, 7.942; 95% CI, 7.889-7.995); and high severity of illness (odds ratio, 8.933; 95% CI, 8.825-9.042). Total estimated albumin cost significantly increased from $325 million in 2009 to $468 million in 2013; (absolute increase of $233 million), p value less than 0.0001. The proportion of hospitalized adults in the United States receiving albumin has increased, with marked, and currently unexplained, geographic variability and variability by hospital size.

Potential Role of Amino Acid/Protein Nutrition and Exercise in Serum Albumin Redox State

Directory of Open Access Journals (Sweden)

Yasuaki Wada

2017-12-01

Full Text Available Albumin is the major protein in the serum of mammals. It is synthesized exclusively in the liver, before being secreted into the circulation. Similar to skeletal muscle protein, albumin synthesis is stimulated by dietary amino acids and proteins as well as exercise. Albumin has three isoforms based on the redox states of the free cysteine residue at position 34. The redox state of serum albumin has long been extensively investigated in terms of oxidative stress-related chronic diseases, with the redox state of serum albumin having been regarded as a marker of systemic oxidative stress. However, according to recent animal studies, the redox state of serum albumin is modulated by albumin turnover and may also reflect amino acid/protein nutritional status. Furthermore, as the redox state of serum albumin is modulated by exercise training, measuring the pre- and post-exercise redox states of serum albumin in athletes may be useful in assessing amino acid/protein nutritional status and exercise-induced oxidative stress, which are closely associated with skeletal muscle adaptive responses. This article extensively reviews serum albumin and the redox state of albumin in the context of amino acid/protein nutritional status and exercise training.

Photochemistry of modified proteins benzophenone-containing bovine serum albumin

International Nuclear Information System (INIS)

Mariano, P.S.; Glover, G.I.; Wilkinson, T.J.

1976-01-01

The results of exploratory and mechanistic studies of the photochemistry of poly-p-benzoyl-acetimido-bovine serum albumin, a modified protein containing photoreactive and photosensitizing groups, are reported. Specifically described are recent findings concerning (1) the synthesis and characterization of a modified bovine serum albumin that contains benzophenone-like moieties, (2) the photochemistry of this modified protein which appeared to involve photoreductive coupling of the benzophenone chromophores to the protein backbone, and (3) triplet energy transfer from modified bovine serum albumin to small molecule acceptors resulting in quenching of the photoreaction. (author)

In vitro evidence for the brain glutamate efflux hypothesis

DEFF Research Database (Denmark)

Helms, Hans Christian; Madelung, Rasmus; Waagepetersen, Helle Sønderby

2012-01-01

resistance values of 1014 ± 70 O cm(2) , and (14) C-D-mannitol permeability values of 0.88 ± 0.13 × 10(-6) cm s(-1) . Unidirectional flux studies showed that L-aspartate and L-glutamate, but not D-aspartate, displayed polarized transport in the brain-to-blood direction, however, all three amino acids......The concentration of the excitotoxic amino acid, L-glutamate, in brain interstitial fluid is tightly regulated by uptake transporters and metabolism in astrocytes and neurons. The aim of this study was to investigate the possible role of the blood-brain barrier endothelium in brain L......-glutamate homeostasis. Transendothelial transport- and accumulation studies of (3) H-L-glutamate, (3) H-L-aspartate, and (3) H-D-aspartate in an electrically tight bovine endothelial/rat astrocyte blood-brain barrier coculture model were performed. After 6 days in culture, the endothelium displayed transendothelial...

Notch signaling mediates granulocyte-macrophage colony-stimulating factor priming-induced transendothelial migration of human eosinophils.

Science.gov (United States)

Liu, L Y; Wang, H; Xenakis, J J; Spencer, L A

2015-07-01

Priming with cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances eosinophil migration and exacerbates the excessive accumulation of eosinophils within the bronchial mucosa of asthmatics. However, mechanisms that drive GM-CSF priming are incompletely understood. Notch signaling is an evolutionarily conserved pathway that regulates cellular processes, including migration, by integrating exogenous and cell-intrinsic cues. This study investigates the hypothesis that the priming-induced enhanced migration of human eosinophils requires the Notch signaling pathway. Using pan Notch inhibitors and newly developed human antibodies that specifically neutralize Notch receptor 1 activation, we investigated a role for Notch signaling in GM-CSF-primed transmigration of human blood eosinophils in vitro and in the airway accumulation of mouse eosinophils in vivo. Notch receptor 1 was constitutively active in freshly isolated human blood eosinophils, and inhibition of Notch signaling or specific blockade of Notch receptor 1 activation during GM-CSF priming impaired priming-enhanced eosinophil transendothelial migration in vitro. Inclusion of Notch signaling inhibitors during priming was associated with diminished ERK phosphorylation, and ERK-MAPK activation was required for GM-CSF priming-induced transmigration. In vivo in mice, eosinophil accumulation within allergic airways was impaired following systemic treatment with Notch inhibitor, or adoptive transfer of eosinophils treated ex vivo with Notch inhibitor. These data identify Notch signaling as an intrinsic pathway central to GM-CSF priming-induced eosinophil tissue migration. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Measurement of lung fluid volumes and albumin exclusion in sheep

International Nuclear Information System (INIS)

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

1989-01-01

A radioactive tracer technique was used to determine interstitial diethylenetriaminepentaacetic acid (DTPA) and albumin distribution volume in sheep lungs. 125 I- and/or 131 I-labeled albumin were injected intravenously and allowed to equilibrate for 24 h. 99m Tc-labeled DTPA and 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 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

Stability of therapeutic albumin solutions used for molecular adsorbent recirculating system-based liver dialysis.

Science.gov (United States)

De Bruyn, Tom; Meijers, Björn; Evenepoel, Pieter; Laub, Ruth; Willems, Ludo; Augustijns, Patrick; Annaert, Pieter

2012-01-01

Mounting evidence suggests beneficial effects of albumin dialysis-based liver support in patients suffering from acute-on-chronic liver failure. Molecular adsorbent recirculating system (MARS) is a nonbiological liver support device, based on the exchange of albumin-bound toxins between the patient's blood and a 20% human serum albumin solution in a secondary circuit. Bound toxins are continuously removed from the circulating albumin by exposure to activated charcoal and an ion-exchange resin. The aim of the present in vitro study was to determine the impact of exposure to charcoal and resin on the ligand binding properties of albumins, containing various levels of stabilizers and obtained from different suppliers (Baxter, CAF-DCF [Red Cross], and Sigma-Aldrich). Albumin binding properties were assessed by measuring equilibrium binding properties of warfarin, diazepam, and salicylate before and after incubation (for up to 7 h) with adsorbing materials; albumin-associated esterase-like activities were also determined. Notable changes in albumin binding upon incubation with adsorbing materials were only observed when using warfarin as a ligand. Affinity of warfarin for the Baxter and Sigma albumins showed a pronounced decrease (higher K(d) ) after the 1-7-h exposure to charcoal or resin. In the absence of adsorbing materials, similar effects were found, indicating that incubation time per se affects albumin binding properties. Following exposure to resin, Baxter albumin binding capacity (B(max)) increased about twofold. For albumin obtained from CAF-DCF, binding affinity and capacity for warfarin were constant under all conditions tested. Esterase-like activities associated with these albumins were either maintained or enhanced (up to 2.5-fold in case of Sigma albumin) following 7-h incubations with adsorbing materials. Our data suggest limited direct influence of the presence of stabilizers in therapeutic albumin solutions on baseline binding properties of human

Fluorescent investigation of the interactions between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and serum albumin: Synchronous fluorescence determination of serum albumin

International Nuclear Information System (INIS)

Cui Fengling; Wang Junli; Cui Yanrui; Li Jianping

2006-01-01

The interactions between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and serum albumin were investigated by fluorescence spectroscopy and UV absorption spectrum under physiological conditions. The results of spectroscopic measurements suggested that N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea should have a strong ability to quench the intrinsic fluorescence of both bovine serum albumin and human serum albumin through static quenching procedure, and the hydrophobic interaction was the predominant intermolecular force stabilizing the complex. Thermodynamic parameter enthalpy changes (ΔH) and entropy changes (ΔS) were calculated according to the Vant'Hoff equation. The binding distances between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and the proteins were evaluated on the basis of the theory of Foester energy transfer. In addition, the effects of other ions on the binding constants of complexes were also discussed. Synchronous fluorescence technology was successfully applied to the determination of serum albumins added to the CPNT solution

Electrokinetic effects and fluid permeability

International Nuclear Information System (INIS)

Berryman, J.G.

2003-01-01

Fluid permeability of porous media depends mainly on connectivity of the pore space and two physical parameters: porosity and a pertinent length-scale parameter. Electrical imaging methods typically establish connectivity and directly measure electrical conductivity, which can then often be related to porosity by Archie's law. When electrical phase measurements are made in addition to the amplitude measurements, information about the pertinent length scale can then be obtained. Since fluid permeability controls the ability to flush unwanted fluid contaminants from the subsurface, inexpensive maps of permeability could improve planning strategies for remediation efforts. Detailed knowledge of fluid permeability is also important for oil field exploitation, where knowledge of permeability distribution in three dimensions is a common requirement for petroleum reservoir simulation and analysis, as well as for estimates on the economics of recovery

Recombinant fusion protein of albumin-retinol binding protein inactivates stellate cells

International Nuclear Information System (INIS)

Choi, Soyoung; Park, Sangeun; Kim, Suhyun; Lim, Chaeseung; Kim, Jungho; Cha, Dae Ryong; Oh, Junseo

2012-01-01

Highlights: ► We designed novel recombinant albumin-RBP fusion proteins. ► Expression of fusion proteins inactivates pancreatic stellate cells (PSCs). ► Fusion proteins are successfully internalized into and inactivate PSCs. ► RBP moiety mediates cell specific uptake of fusion protein. -- Abstract: Quiescent pancreatic- (PSCs) and hepatic- (HSCs) stellate cells store vitamin A (retinol) in lipid droplets via retinol binding protein (RBP) receptor and, when activated by profibrogenic stimuli, they transform into myofibroblast-like cells which play a key role in the fibrogenesis. Despite extensive investigations, there is, however, currently no appropriate therapy available for tissue fibrosis. We previously showed that the expression of albumin, composed of three homologous domains (I–III), inhibits stellate cell activation, which requires its high-affinity fatty acid-binding sites asymmetrically distributed in domain I and III. To attain stellate cell-specific uptake, albumin (domain I/III) was coupled to RBP; RBP-albumin domain III (R-III) and albumin domain I -RBP-albumin III (I-R-III). To assess the biological activity of fusion proteins, cultured PSCs were used. Like wild type albumin, expression of R-III or I-R-III in PSCs after passage 2 (activated PSCs) induced phenotypic reversal from activated to fat-storing cells. On the other hand, R-III and I-R-III, but not albumin, secreted from transfected 293 cells were successfully internalized into and inactivated PSCs. FPLC-purified R-III was found to be internalized into PSCs via caveolae-mediated endocytosis, and its efficient cellular uptake was also observed in HSCs and podocytes among several cell lines tested. Moreover, tissue distribution of intravenously injected R-III was closely similar to that of RBP. Therefore, our data suggest that albumin-RBP fusion protein comprises of stellate cell inactivation-inducing moiety and targeting moiety, which may lead to the development of effective anti

Amino acid substitutions in inherited albumin variants from Amerindian and Japanese populations

International Nuclear Information System (INIS)

Takahashi, N.; Takahashi, Y.; Isobe, T.; Putnam, F.W.; Fujita, M.; Satoh, C.; Neel, J.V.

1987-01-01

The authors report an effort to determine the basis for the altered migration of seven inherited albumin variants detected by one-dimensional electrophoresis in population surveys involving tribal Amerindians and Japanese children. An amino acid substitution has thus far been determined for four of the variants. The randomness in the albumin polypeptide of these and the other sixteen independently ascertained amino acid substitutions of albumin and proalbumin thus far established was analyzed; the clustering of eight of these at two positions in the six-amino acid propeptide sequence seems noteworthy. By comparison with other proteins studied by electrophoresis, albumin exhibits average variability. It is a paradox that individuals who, for genetic reasons, lack albumin exhibit no obvious ill effects; yet, electrophoretic variants of albumin are no more numerous than are variants of proteins, the absence of which results in severe disease

Changes in protein metabolism after gastric resection studied by 125I-albumin

International Nuclear Information System (INIS)

Beno, I.; Cerven, J.

1976-01-01

The changes were studied in the metabolism of protein using albumin- 125 I in seven patients with benign conditions of the stomach or duodenum before gastrectomy and starting with the second week after the surgery. In the postoperative period body weight was found to be significantly reduced, there was a drop in erythrocyte count, and blood hemoglobin and plasma albumin concentration were decreased. There was a significant rise of plasma volume during this period. Compared with the preoperative findings, the intravascular albumin pool was diminished by 11%, the extravascular albumin pool by 19.%, so that the overall albumin pool was postoperatively found to be reduced by 1/6. (author)

Molecular Structure-Affinity Relationship of Flavonoids in Lotus Leaf (Nelumbo nucifera Gaertn.) on Binding to Human Serum Albumin and Bovine Serum Albumin by Spectroscopic Method.

Science.gov (United States)

Tang, Xiaosheng; Tang, Ping; Liu, Liangliang

2017-06-23

Lotus leaf has gained growing popularity as an ingredient in herbal formulations due to its various activities. As main functional components of lotus leaf, the difference in structure of flavonoids affected their binding properties and activities. In this paper, the existence of 11 flavonoids in lotus leaf extract was confirmed by High Performance Liquid Chromatography (HPLC) analysis and 11 flavonoids showed various contents in lotus leaf. The interactions between lotus leaf extract and two kinds of serum albumins (human serum albumin (HSA) and bovine serum albumin (BSA)) were investigated by spectroscopic methods. Based on the fluorescence quenching, the interactions between these flavonoids and serum albumins were further checked in detail. The relationship between the molecular properties of flavonoids and their affinities for serum albumins were analyzed and compared. The hydroxylation on 3 and 3' position increased the affinities for serum albumins. Moreover, both of the methylation on 3' position of quercetin and the C₂=C₃ double bond of apigenin and quercetin decreased the affinities for HSA and BSA. The glycosylation lowered the affinities for HSA and BSA depending on the type of sugar moiety. It revealed that the hydrogen bond force played an important role in binding flavonoids to HSA and BSA.

Studies of quality control of 99mTc-labelled macroaggregated albumin: Pt. 1

International Nuclear Information System (INIS)

Fukuoka, Masamichi; Kobayashi, Tetsu; Tanaka, Akira; Satoh, Takemichi; Kubodera, Akiko

1993-01-01

The aggregative condition of albumin was investigated using bovine serum albumin (BSA) as a model for quality control of 99m Tc-macroaggregated albumin ( 99 Tc-MAA). Uniformalized aggregates were obtained from the oxidized non-mercapt-type of BSA by heating. The size of the aggregates was affected by the pH and the types of buffer solutions used as well as the concentrations of albumin and buffers. The β form structure of the albumin was more stable on heating and this may contribute to its aggregation. Aggregation of oxidized non-mercaptalbumin afforded a portion of smaller sized particles in MAA, this being an inappropriate factor for scintiscanning of lungs. Our results suggest that it is necessary to remove oxidized type albumin from human serum albumin as the starting material, in order to prepare MAA with a uniform and larger particle size. (Author)

The preparation of albumin as a biological drug from human plasma by fiber filtration

Directory of Open Access Journals (Sweden)

Mousavi Hosseini K

2011-08-01

Full Text Available "nBackground: In recent years, consumption of whole-blood for the treatment of patients has decreased but use of biological plasma-derived medicines such as albumin, immunoglobulin and coagulation factors have increased instead. Paying attention to albumin molecular structure is important for its isolation from human plasma. Albumin is a single-chain protein consisting of about 585 amino acids and a molecular weight of 66500 Daltons. Albumin is a stable molecule and it is spherical in shape. There are different methods for human albumin preparation. Considering the large consumption of this biological drug in clinical settings, methods with fewer steps in production line are of big advantage in saving time and manufacturing more products."n "nMethods: In this project, we prepared human albumin using hollow fiber cartridges in order to omit the rework on fraction V+VI. Human albumin is usually produced by the application of cold ethanol method, where albumin is obtained from fraction V by doing a rework on fraction V+VI to separate fraction V."n "nResults: In the current work, human albumin was prepared from fraction V+VI by the help of hollow fiber cartridges. With a concentration of 20%, the obtained albumin had 96.5% of monomer and 3.5% of polymer and polymer aggregate."n "nConclusion: Comparing the obtained human albumin with a number of commercial human albumin samples by the use of SDS-page, the results were satisfactory regarding the 3.5 percent polymer and aggregate rate for the prepared albumin.

Paclitaxel Albumin-stabilized Nanoparticle Formulation

Science.gov (United States)

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.

Albumin: pathophysiologic basis of its role in the treatment of cirrhosis and its complications.

Science.gov (United States)

Garcia-Martinez, Rita; Caraceni, Paolo; Bernardi, Mauro; Gines, Pere; Arroyo, Vicente; Jalan, Rajiv

2013-11-01

Since the introduction of human serum albumin as a plasma expander in the 1940s, considerable research has allowed a better understanding of its biochemical properties and potential clinical benefits. Albumin has a complex structure, which is responsible for a variety of biological functions. In disease, the albumin molecule is susceptible to modifications that may alter its biological activity. During the last decades, different methods to measure albumin function have been developed. Recent studies have shown that not only albumin concentration but also albumin function is reduced in liver failure. This observation led to the concept of effective albumin concentration, which represents the fact that plasma albumin concentration does not reflect its function. Indeed, in liver disease albumin function is several times less than its concentration. In patients with cirrhosis, albumin infusion reduces mortality in patients with spontaneous bacterial peritonitis and improves outcome following large volume paracentesis. In combination with vasoconstrictors, albumin is useful in the management of patients with hepatorenal syndrome. Its role is being investigated in a large number of indications, which rely on its volume and nonvolume expansion functions such as stroke, severe sepsis, Alzheimer's disease, malaria, burns, and ovarian hyperstimulation syndrome. This review explores the above concepts, reviews the available evidence for the use of albumin in liver diseases, defines therapeutic limitations, and explores the challenges that should be addressed in future research. Copyright © 2013 American Association for the Study of Liver Diseases.

On-Chip Immunoassay for Determination of Urinary Albumin

Directory of Open Access Journals (Sweden)

Adisorn Tuantranont

2009-12-01

Full Text Available An immunoassay performed on a portable microfluidic device was evaluated for the determination of urinary albumin. An increase in absorbance at 500 nm resulting from immunoagglutination was monitored directly on the poly(dimethylsiloxane (PDMS microchip using a portable miniature fibre-optic spectrometer. A calibration curve was linear up to 10 mg L–1 (r2 = 0.993, with a detection limit of 0.81 mg L–1 (S/N = 3. The proposed system showed good precision, with relative standard deviations (RSDs of 5.1%, when evaluated with 10 mg L–1 albumin (n = 10. Determination of urinary albumin with the proposed system gave results highly similar to those determined by the conventional spectrophotometric method using immunoturbidimetric detection (r2 = 0.995; n = 15.

Micropinocytic ingestion of glycosylated albumin by isolated microvessels: possible role in pathogenesis of diabetic microangiopathy.

OpenAIRE

Williams, S K; Devenny, J J; Bitensky, M W

1981-01-01

Microvessels isolated from rat epididymal fat exhibit differential vesicular ingestion rates for unmodified and non-enzymatically 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 concentra...

Compact rock material gas permeability properties

Energy Technology Data Exchange (ETDEWEB)

Wang, Huanling, E-mail: whl_hm@163.com [Key Laboratory of Coastal Disaster and Defence, Ministry of Education, Hohai University, Nanjing 210098 (China); LML, University of Lille, Cite Scientifique, 59655 Villeneuve d’Ascq (France); Xu, Weiya; Zuo, Jing [Institutes of Geotechnical Engineering, Hohai University, Nanjing 210098 (China)

2014-09-15

Natural compact rocks, such as sandstone, granite, and rock salt, are the main materials and geological environment for storing underground oil, gas, CO{sub 2,} shale gas, and radioactive waste because they have extremely low permeabilities and high mechanical strengths. Using the inert gas argon as the fluid medium, the stress-dependent permeability and porosity of monzonitic granite and granite gneiss from an underground oil storage depot were measured using a permeability and porosity measurement system. Based on the test results, models for describing the relationships among the permeability, porosity, and confining pressure of rock specimens were analyzed and are discussed. A power law is suggested to describe the relationship between the stress-dependent porosity and permeability; for the monzonitic granite and granite gneiss (for monzonitic granite (A-2), the initial porosity is approximately 4.05%, and the permeability is approximately 10{sup −19} m{sup 2}; for the granite gneiss (B-2), the initial porosity is approximately 7.09%, the permeability is approximately 10{sup −17} m{sup 2}; and the porosity-sensitivity exponents that link porosity and permeability are 0.98 and 3.11, respectively). Compared with moderate-porosity and high-porosity rocks, for which φ > 15%, low-porosity rock permeability has a relatively lower sensitivity to stress, but the porosity is more sensitive to stress, and different types of rocks show similar trends. From the test results, it can be inferred that the test rock specimens’ permeability evolution is related to the relative particle movements and microcrack closure.

Permeability During Magma Expansion and Compaction

Science.gov (United States)

Gonnermann, Helge. M.; Giachetti, Thomas; Fliedner, Céline; Nguyen, Chinh T.; Houghton, Bruce F.; Crozier, Joshua A.; Carey, Rebecca J.

2017-12-01

Plinian lapilli from the 1060 Common Era Glass Mountain rhyolitic eruption of Medicine Lake Volcano, California, were collected and analyzed for vesicularity and permeability. A subset of the samples were deformed at a temperature of 975°, under shear and normal stress, and postdeformation porosities and permeabilities were measured. Almost all undeformed samples fall within a narrow range of vesicularity (0.7-0.9), encompassing permeabilities between approximately 10-15 m2 and 10-10 m2. A percolation threshold of approximately 0.7 is required to fit the data by a power law, whereas a percolation threshold of approximately 0.5 is estimated by fitting connected and total vesicularity using percolation modeling. The Glass Mountain samples completely overlap with a range of explosively erupted silicic samples, and it remains unclear whether the erupting magmas became permeable at porosities of approximately 0.7 or at lower values. Sample deformation resulted in compaction and vesicle connectivity either increased or decreased. At small strains permeability of some samples increased, but at higher strains permeability decreased. Samples remain permeable down to vesicularities of less than 0.2, consistent with a potential hysteresis in permeability-porosity between expansion (vesiculation) and compaction (outgassing). We attribute this to retention of vesicle interconnectivity, albeit at reduced vesicle size, as well as bubble coalescence during shear deformation. We provide an equation that approximates the change in permeability during compaction. Based on a comparison with data from effusively erupted silicic samples, we propose that this equation can be used to model the change in permeability during compaction of effusively erupting magmas.

Changes in the pharmacokinetics of teicoplanin in patients with hyperglycaemic hypoalbuminaemia: Impact of albumin glycosylation on the binding of teicoplanin to albumin.

Science.gov (United States)

Enokiya, Tomoyuki; Muraki, Yuichi; Iwamoto, Takuya; Okuda, Masahiro

2015-08-01

There is large interindividual variability in serum teicoplanin (TEIC) concentrations after administration of a loading dose, and the factors that influence the pharmacokinetics of TEIC are disputed. The aim of this study was to clarify changes in the pharmacokinetics of TEIC that occur in patients with hyperglycaemia as well as the impact of albumin glycosylation on the pharmacokinetics of TEIC. This study consisted of retrospective and prospective investigations. The pharmacokinetic parameters of TEIC were retrospectively compared between patients receiving TEIC treatment. Ninety-four patients were divided into four groups according to their serum albumin and blood glucose concentrations [(i) hyperglycaemic hypoalbuminaemia (albuminalbumin≥3.0g/dL) (n=9); and (iv) non-hyperglycaemic normoalbuminaemia (n=40)]. In addition, the concentration of glycosylated albumin was prospectively determined in 28 patients. At 12h after administration of a loading dose, patients with hyperglycaemic hypoalbuminaemia displayed significantly lower serum TEIC concentrations (Palbumin was significantly correlated with the association constant (Ka) of TEIC for albumin (r=0.53, P=0.004) and the Vd (r=0.41, P=0.031). These results suggest that hyperglycaemic hypoalbuminaemia lowers the serum TEIC concentration, which is attributable to the decreased Ka and increased Vd of TEIC by albumin glycosylation. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Stimulation of albumin gene transcription by insulin in primary cultures of rat hepatocytes

International Nuclear Information System (INIS)

Lloyd, C.E.; Kalinyak, J.E.; Hutson, S.M.; Jefferson, L.S.

1987-01-01

The first goal of the work reported here was to prepare single-stranded DNA sequences for use in studies on the regulation of albumin gene expression. A double-stranded rat albumin cDNA clone was subcloned into the bacteriophage vector M13mp7. Single-stranded recombinant clones were screened for albumin sequences containing either the mRNA strand or the complementary strand. Two clones were selected that contained the 1200 nucleotide long 3' end of the albumin sequence. DNA from the clone containing the mRNA strand was used as a template for DNA polymerase I to prepare a radiolabeled, single-stranded cDNA to albumin mRNA. This radiolabeled cDNA probe was used to quantitate the relative abundance of albumin mRNA in samples of total cellular RNA. DNA from the clone containing the complementary strand was used to measure relative rates of albumin gene transcription in isolated nuclei. The second goal was to use the single-stranded DNA probes to investigate the mechanism of the insulin-mediated stimulation of albumin synthesis in primary cultures of rat hepatocytes. Addition of insulin to hepatocytes maintained in a chemically defined, serum-free medium for 40 h in the absence of any hormones resulted in a specific 1.5- to 2.5-fold stimulation of albumin gene transcription that was maximal at 3 h and was maintained above control values for at least 24 h. The rate of albumin gene transcription in nuclei isolated from livers of diabetic rats was reduced to 50% of the value recorded in control nuclei. Taken together, these findings demonstrate that insulin regulates synthesis of albumin at the level of gene transcription

Uptake and metabolism of polymerized albumin by rat liver. Role of the scavenger receptor

International Nuclear Information System (INIS)

Wright, T.L.; Roll, F.J.; Jones, A.L.; Weisiger, R.A.

1988-01-01

Hepatitis B virus binds avidly to albumin polymers, which in turn may mediate viral attachment to liver cells. This hypothesis is critically dependent on prior results obtained using glutaraldehyde-polymerized human serum albumin as a model for naturally occurring albumin species. We used the perfused rat liver to characterize the uptake, cellular distribution, and metabolism of glutaraldehyde-polymerized human albumin. 125 I-glutaraldehyde-polymerized human albumin was efficiently removed from the perfusate by the liver (29% extraction). However, few autoradiographic grains were located over hepatic parenchymal cells (6%). Instead, most glutaraldehyde-polymerized human albumin appeared to be removed by endothelial (59%) or Kupffer (31%) cells. Hepatic uptake was strongly inhibited by formaldehyde-treated monomeric albumin, a known ligand of the endothelial scavenger receptor for chemically modified proteins. After uptake, most glutaraldehyde-polymerized human albumin was rapidly degraded and released into the perfusate (74% within 60 min). This process was blocked by chloroquine and leupeptin, suggesting that it involves lysosomal acid hydrolases. We conclude that glutaraldehyde-polymerized albumin is efficiently cleared and degraded by the endothelial scavenger pathway. Glutaraldehyde-polymerized albumin therefore appears to be a poor model for predicting the hepatic handling of naturally occurring albumin species bound to hepatitis B virions. Even if viral particles were to follow this pathway, few would enter parenchymal hepatocytes

Serum Albumin Predicts Long-Term Neurological Outcomes After Acute Spinal Cord Injury.

Science.gov (United States)

Tong, Bobo; Jutzeler, Catherine R; Cragg, Jacquelyn J; Grassner, Lukas; Schwab, Jan M; Casha, Steve; Geisler, Fred; Kramer, John L K

2018-01-01

There is a need to identify reliable biomarkers of spinal cord injury recovery for clinical practice and clinical trials. Our objective was to correlate serum albumin levels with spinal cord injury neurological outcomes. We performed a secondary analysis of patients with traumatic spinal cord injury (n = 591) participating in the Sygen clinical trial. Serum albumin concentrations were obtained as part of routine blood chemistry analysis, at trial entry (24-72 hours), 1, 2, and 4 weeks after injury. The primary outcomes were "marked recovery" and lower extremity motor scores, derived from the International Standards for the Neurological Classification of Spinal Cord Injury. Data were analyzed with multivariable logistic and linear regression to adjust for potential confounders. Serum albumin was significantly associated with spinal cord injury neurological outcomes. Higher serum albumin concentrations at 1, 2, and 4 weeks were associated with higher 52-week lower extremity motor score. Similarly, the odds of achieving "marked neurological recovery" was greater for individuals with higher serum albumin concentrations. The association between serum albumin concentrations and neurological outcomes was independent of initial injury severity, treatment with GM-1, and polytrauma. In spinal cord injury, serum albumin is an independent marker of long-term neurological outcomes. Serum albumin could serve as a feasible biomarker for prognosis at the time of injury and stratification in clinical trials.

Albumin-bound fatty acids but not albumin itself alter redox balance in tubular epithelial cells and induce a peroxide-mediated redox-sensitive apoptosis

Science.gov (United States)

Ruggiero, Christine; Elks, Carrie M.; Kruger, Claudia; Cleland, Ellen; Addison, Kaity; Noland, Robert C.

2014-01-01

Albuminuria is associated with metabolic syndrome and diabetes. It correlates with the progression of chronic kidney disease, particularly with tubular atrophy. The fatty acid load on albumin significantly increases in obesity, presenting a proinflammatory environment to the proximal tubules. However, little is known about changes in the redox milieu during fatty acid overload and how redox-sensitive mechanisms mediate cell death. Here, we show that albumin with fatty acid impurities or conjugated with palmitate but not albumin itself compromised mitochondrial and cell viability, membrane potential and respiration. Fatty acid overload led to a redox imbalance which deactivated the antioxidant protein peroxiredoxin 2 and caused a peroxide-mediated apoptosis through the redox-sensitive pJNK/caspase-3 pathway. Transfection of tubular cells with peroxiredoxin 2 was protective and mitigated apoptosis. Mitochondrial fatty acid entry and ceramide synthesis modulators suggested that mitochondrial β oxidation but not ceramide synthesis may modulate lipotoxic effects on tubular cell survival. These results suggest that albumin overloaded with fatty acids but not albumin itself changes the redox environment in the tubules, inducing a peroxide-mediated redox-sensitive apoptosis. Thus, mitigating circulating fatty acid levels may be an important factor in both preserving redox balance and preventing tubular cell damage in proteinuric diseases. PMID:24500687

Determination of albumin in bronchoalveolar lavage fluid by flow-injection fluorometry using chromazurol S.

Science.gov (United States)

Sato, Takaji; Saito, Yoshihiro; Chikuma, Masahiko; Saito, Yutaka; Nagai, Sonoko

2008-03-01

A highly sensitive flow injection fluorometry for the determination of albumin was developed and applied to the determination of albumin in human bronchoalveolar lavage fluids (BALF). This method is based on binding of chromazurol S (CAS) to albumin. The calibration curve was linear in the range of 5-200 microg/ml of albumin. A highly linear correlation (r=0.986) was observed between the albumin level in BALF samples (n=25) determined by the proposed method and by a conventional fluorometric method using CAS (CAS manual method). The IgG interference was lower in the CAS flow injection method than in the CAS manual method. The albumin level in BALF collected from healthy volunteers (n=10) was 58.5+/-13.1 microg/ml. The albumin levels in BALF samples obtained from patients with sarcoidosis and idiopathic pulmonary fibrosis were increased. This finding shows that the determination of albumin levels in BALF samples is useful for investigating lung diseases and that CAS flow injection method is promising in the determination of trace albumin in BALF samples, because it is sensitive and precise.

Serum Albumin Levels and Economic Status in Japanese Older Adults.

Directory of Open Access Journals (Sweden)

Asami Ota

Full Text Available 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.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.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.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.

Urinary albumin excretion. An independent predictor of ischemic heart disease

DEFF Research Database (Denmark)

Borch-Johnsen, K; Feldt-Rasmussen, B; Strandgaard, S

1999-01-01

Cross-sectional studies suggest that an increased urinary albumin excretion rate is associated with cardiovascular disease, dyslipidemia, and hypertension. The purpose of this study was to analyze prospectively whether the urinary albumin-to -creatinine (A/C) ratio can independently predict...... ischemic heart disease (IHD) in a population-based cohort. In 1983, urinary albumin and creatinine levels were measured, along with the conventional atherosclerotic risk factors, in 2085 consecutive participants without IHD, renal disease, urinary tract infection, or diabetes mellitus. The participants...

Clinical studies of alveolar-capillary permeability using technetium-99m DTPA aerosol

International Nuclear Information System (INIS)

Sundram, F.X.

1995-01-01

Soluble radioaerosols such as technetium-99m diethylene triamine pentacetate (DTPA) permit simple quantitative studies of alveolar-capillary permeability to be performed, since the submicronic aerosols are deposited mainly at the lung periphery and are cleared across the alveolar-capillary membrane. Regional alterations in permeability can also be noted using this radionuclide technique. We have measured the pulmonary epithelial permeability in normal subjects and the alteration in smokers, glue-sniffers, patients with inhalation burns, chronic obstructive pulmonary disease (COPD) and patients with lung metastases from thyroid cancer treated with radioiodine 131 I. In the normal volunteers, the time taken for 50% of inhaled 99m Tc DTPA to be cleared from the lungs (T1/2) was 66 minutes±1 sd of 12 mins. The smokers had a mean T1/2 of 20 mins±1 sd 4 min. In the hard-core glue-sniffing group, the majority were smokers who had stopped smoking and glue-sniffing for periods varying from 1 day to 42 days, and it was possible to note the changes in clearance times against period of abstinence. In the patients with inhalation burns, there was change in lung clearance arising from pulmonary epithelial damage; these patients showed increased rate of clearance (short T1/2) with mean T1/2 of 36 min±1 sd of 11 mins, while the retention images revealed regional lung damage in moderately severe inhalation burns. Twenty-four patients with COPD had inhalation scans done with Tc-99m tin colloid radioaerosol, and these images were compared with the perfusion lung scans done with 99m Tc macroaggregated albumin (MAA); in general the perfusion images matched the defects noted in the inhalation scans. The 99m Tc DTPA clearance rate in these patients was normal i.e. T1/2=78±14 mins. In the thyroid cancer patients with lung metastases, who had high doses of radioiodine treatment, the T1/2 values were normal or prolonged slightly, mean T1/2=76 min±23. (author)

Binding of anandamide to bovine serum albumin

DEFF Research Database (Denmark)

Bojesen, I.N.; Hansen, Harald S.

2003-01-01

The endocannabinoid anandamide is of lipid nature and may thus bind to albumin in the vascular system, as do fatty acids. The knowledge of the free water-phase concentration of anandamide is essential for the investigations of its transfer from the binding protein to cellular membranes, because...... a water-phase shuttle of monomers mediates such transfers. We have used our method based upon the use of albumin-filled red cell ghosts as a dispersed biological "reference binder" to measure the water-phase concentrations of anandamide. These concentrations were measured in buffer (pH 7.3) in equilibrium...... that BSA has one high-affinity binding site for anandamide at all four temperatures. The free energy of anandamide binding (¿G) is calculated to -43.05 kJ mol with a large enthalpy (¿H ) contribution of -42.09 kJ mol. Anandamide has vasodilator activity, and the binding to albumin may mediate its transport...

Analysis of albumin Raman scattering in visible and near-infrared ranges

Science.gov (United States)

Lykina, Anastasia A.; Artemyev, Dmitry N.

2018-04-01

In this work the analysis of the shape and intensity of albumin Raman signals in visible and near-IR ranges was carried out. The experimental setup using lasers from the visible region first of all excites the fluorescence of the albumin solution, the main contribution to which is produced by sodium chloride, which is a component of the tested sample. At the same time, lasers from the near-infrared range excited the Raman signal of albumin most effectively. It was found that the highest ratio of Raman scattering to autofluorescence intensities in the detected signal was obtained using a laser with a wavelength of 1064 nm. To determine the albumin solution concentration by type of spectrum, a regression approach with the projection to latent structures method was applied. The lowest predicted error of albumin concentration of 2-3 g/l was obtained by using the near-infrared range lasers.

Characterization of anticancer, DNase and antifungal activity of pumpkin 2S albumin.

Science.gov (United States)

Tomar, Prabhat Pratap Singh; Nikhil, Kumar; Singh, Anamika; Selvakumar, Purushotham; Roy, Partha; Sharma, Ashwani Kumar

2014-06-13

The plant 2S albumins exhibit a spectrum of biotechnologically exploitable functions. Among them, pumpkin 2S albumin has been shown to possess RNase and cell-free translational inhibitory activities. The present study investigated the anticancer, DNase and antifungal activities of pumpkin 2S albumin. The protein exhibited a strong anticancer activity toward breast cancer (MCF-7), ovarian teratocarcinoma (PA-1), prostate cancer (PC-3 and DU-145) and hepatocellular carcinoma (HepG2) cell lines. Acridine orange staining and DNA fragmentation studies indicated that cytotoxic effect of pumpkin 2S albumin is mediated through induction of apoptosis. Pumpkin 2S albumin showed DNase activity against both supercoiled and linear DNA and exerted antifungal activity against Fusarium oxysporum. Secondary structure analysis by CD showed that protein is highly stable up to 90°C and retains its alpha helical structure. These results demonstrated that pumpkin 2S albumin is a multifunctional protein with host of potential biotechnology applications. Copyright © 2014 Elsevier Inc. All rights reserved.

Fluorescent investigation of the interactions between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and serum albumin: Synchronous fluorescence determination of serum albumin

Energy Technology Data Exchange (ETDEWEB)

Cui Fengling [School of Chemistry and Environmental Science, Key Laboratory for Environmental Pollution Control Technology of Henan Province, Henan Normal University, Xinxiang, Hennan 453007 (China)]. E-mail: fenglingcui@hotmail.com; Wang Junli [School of Chemistry and Environmental Science, Key Laboratory for Environmental Pollution Control Technology of Henan Province, Henan Normal University, Xinxiang, Hennan 453007 (China); Cui Yanrui [School of Chemistry and Environmental Science, Key Laboratory for Environmental Pollution Control Technology of Henan Province, Henan Normal University, Xinxiang, Hennan 453007 (China); Li Jianping [School of Chemistry and Environmental Science, Key Laboratory for Environmental Pollution Control Technology of Henan Province, Henan Normal University, Xinxiang, Hennan 453007 (China)

2006-07-07

The interactions between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and serum albumin were investigated by fluorescence spectroscopy and UV absorption spectrum under physiological conditions. The results of spectroscopic measurements suggested that N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea should have a strong ability to quench the intrinsic fluorescence of both bovine serum albumin and human serum albumin through static quenching procedure, and the hydrophobic interaction was the predominant intermolecular force stabilizing the complex. Thermodynamic parameter enthalpy changes ({delta}H) and entropy changes ({delta}S) were calculated according to the Vant'Hoff equation. The binding distances between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and the proteins were evaluated on the basis of the theory of Foester energy transfer. In addition, the effects of other ions on the binding constants of complexes were also discussed. Synchronous fluorescence technology was successfully applied to the determination of serum albumins added to the CPNT solution.

Albumin Overload and PINK1/Parkin Signaling-Related Mitophagy in Renal Tubular Epithelial Cells.

Science.gov (United States)

Tan, Jin; Xie, Qi; Song, Shuling; Miao, Yuyang; Zhang, Qiang

2018-03-01

BACKGROUND Albumin, as a major urinary protein component, is a risk factor for chronic kidney disease progression. Mitochondrial dysfunction is one of the main causes of albumin-induced proximal tubule cells injury. Mitophagy is considered as a pivotal protective mechanism for the elimination of dysfunctional mitochondria. The objective of this research was to determine whether albumin overload-induced mitochondrial dysfunction can activate PINK1/Parkin-mediated mitophagy in renal tubular epithelial cells (TECs). MATERIAL AND METHODS Immunofluorescence assay and Western blot assay were used to detect the effects of albumin overload on autophagy marker protein LC3. Transmission electron microscopy and Western blot assay were used to investigate the role of albumin in mitochondrial injury. Western blot assay and co-localization of acidic lysosomes and mitochondria assay were employed to detect the activation of mitophagy induced by albumin. Finally, we explored the role of PINK1/Parkin signaling in albumin-induced mitophagy by inhibiting mitophagy by knockdown of PARK2 (Parkin) level. RESULTS Immunofluorescence and Western blot results showed that the expression level of LC3-II increased, and the maximum increase point was observed after 8 h of albumin treatment. Transmission electron microscopy results demonstrated that albumin overload-induced mitochondrial injury and quantity of autophagosomes increased. Additionally, expression of PINK1 and cytosolic cytochrome C increased and mitochondria cytochrome C decreased in the albumin group. The co-localization of acidic lysosomes and mitochondria demonstrated that the number of albumin overload-induced mitophagy-positive dots increased. The transient transfection of PARK2 siRNA result showed knockdown of the expression level of PARK2 can inhibit mitophagy induced by albumin. CONCLUSIONS In conclusion, our study suggests that mitochondrial dysfunction activates the PINK1/Parkin signaling and mitophagy in renal tubular

Film Permeability Determination Using Static Permeability Cells

Science.gov (United States)

The permeability of tarps to soil fumigant pesticides varies depending on the active ingredient chemical: dimethyl disulfide (DMDS), methyl bromide, chloropicrin, or other. The diffusion rate can be represented by the mass transfer coefficient (MTC).

Recombinant fusion protein of albumin-retinol binding protein inactivates stellate cells

Energy Technology Data Exchange (ETDEWEB)

Choi, Soyoung; Park, Sangeun; Kim, Suhyun [Laboratory of Cellular Oncology, Korea University Graduate School of Medicine, Ansan, Gyeonggi do 425-707 (Korea, Republic of); Lim, Chaeseung [Department of Laboratory Medicine, Korea University Guro Hospital, Seoul 152-703 (Korea, Republic of); Kim, Jungho [Department of Life Science, Sogang University, Seoul 121-742 (Korea, Republic of); Cha, Dae Ryong [Department of Internal Medicine, Korea University Ansan Hospital, Ansan, Gyeonggi do 425-020 (Korea, Republic of); Oh, Junseo, E-mail: ohjs@korea.ac.kr [Laboratory of Cellular Oncology, Korea University Graduate School of Medicine, Ansan, Gyeonggi do 425-707 (Korea, Republic of)

2012-02-03

Highlights: Black-Right-Pointing-Pointer We designed novel recombinant albumin-RBP fusion proteins. Black-Right-Pointing-Pointer Expression of fusion proteins inactivates pancreatic stellate cells (PSCs). Black-Right-Pointing-Pointer Fusion proteins are successfully internalized into and inactivate PSCs. Black-Right-Pointing-Pointer RBP moiety mediates cell specific uptake of fusion protein. -- Abstract: Quiescent pancreatic- (PSCs) and hepatic- (HSCs) stellate cells store vitamin A (retinol) in lipid droplets via retinol binding protein (RBP) receptor and, when activated by profibrogenic stimuli, they transform into myofibroblast-like cells which play a key role in the fibrogenesis. Despite extensive investigations, there is, however, currently no appropriate therapy available for tissue fibrosis. We previously showed that the expression of albumin, composed of three homologous domains (I-III), inhibits stellate cell activation, which requires its high-affinity fatty acid-binding sites asymmetrically distributed in domain I and III. To attain stellate cell-specific uptake, albumin (domain I/III) was coupled to RBP; RBP-albumin{sup domain} {sup III} (R-III) and albumin{sup domain} {sup I}-RBP-albumin{sup III} (I-R-III). To assess the biological activity of fusion proteins, cultured PSCs were used. Like wild type albumin, expression of R-III or I-R-III in PSCs after passage 2 (activated PSCs) induced phenotypic reversal from activated to fat-storing cells. On the other hand, R-III and I-R-III, but not albumin, secreted from transfected 293 cells were successfully internalized into and inactivated PSCs. FPLC-purified R-III was found to be internalized into PSCs via caveolae-mediated endocytosis, and its efficient cellular uptake was also observed in HSCs and podocytes among several cell lines tested. Moreover, tissue distribution of intravenously injected R-III was closely similar to that of RBP. Therefore, our data suggest that albumin-RBP fusion protein comprises

Permeability testing of biomaterial membranes

Energy Technology Data Exchange (ETDEWEB)

Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B [NMI Natural and Medical Sciences Institute at University Tuebingen, Markwiesenstr. 55, D-72770 Reutlingen (Germany); Ahlers, M [GELITA AG, Gammelsbacher Str. 2, D-69412 Eberbach (Germany)], E-mail: schlosshauer@nmi.de

2008-09-01

The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation.

Permeability testing of biomaterial membranes

International Nuclear Information System (INIS)

Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B; Ahlers, M

2008-01-01

The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation

Albumin treatment regimen for type 1 hepatorenal syndrome: a dose-response meta-analysis.

Science.gov (United States)

Salerno, Francesco; Navickis, Roberta J; Wilkes, Mahlon M

2015-11-25

Recommended treatment for type 1 hepatorenal syndrome consists of albumin and vasoconstrictor. The optimal albumin dose remains poorly characterized. This meta-analysis aimed to determine the impact of albumin dose on treatment outcomes. Clinical studies of type 1 hepatorenal syndrome treatment with albumin and vasoconstrictor were sought. Search terms included: hepatorenal syndrome; albumin; vasoconstrictor; terlipressin; midodrine; octreotide; noradrenaline; and norepinephrine. A meta-analysis was performed of hepatorenal syndrome reversal and survival in relation to albumin dose. Nineteen clinical studies with 574 total patients were included, comprising 8 randomized controlled trials, 8 prospective studies and 3 retrospective studies. The pooled percentage of patients achieving hepatorenal syndrome reversal was 49.5% (95% confidence interval, 40.0-59.1%). Increments of 100 g in cumulative albumin dose were accompanied by significantly increased survival (hazard ratio, 1.15; 95% confidence interval, 1.02-1.31; p = 0.023). A non-significant increase of similar magnitude in hepatorenal syndrome reversal was also observed (odds ratio, 1.15; 95% confidence interval, 0.97-1.37; p = 0.10). Expected survival rates at 30 days among patients receiving cumulative albumin doses of 200, 400 and 600 g were 43.2% (95% confidence interval, 36.4-51.3%), 51.4% (95% confidence interval, 46.3-57.1%) and 59.0% (95% confidence interval, 51.9-67.2), respectively. Neither survival nor hepatorenal syndrome reversal was significantly affected by vasoconstrictor dose or type, treatment duration, age, baseline serum creatinine, bilirubin or albumin, baseline mean arterial pressure, or study design, size or time period. This meta-analysis suggests a dose-response relationship between infused albumin and survival in patients with type 1 hepatorenal syndrome. The meta-analysis provides the best current evidence on the potential role of albumin dose selection in improving outcomes of

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

Science.gov (United States)

Vincent, Jean-Louis; Russell, James A; Jacob, Matthias; Martin, Greg; Guidet, Bertrand; Wernerman, Jan; Ferrer, Ricard; Roca, Ricard Ferrer; McCluskey, Stuart A; Gattinoni, Luciano

2014-07-16

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.

Determination of serum albumin with tribromoarsenazo by spectrophotometry

Directory of Open Access Journals (Sweden)

Qing-Zhou Zhai

2007-08-01

Full Text Available The reaction of tribromoarsenazo(TB-ASA with serum albumin in the presence of emulgent OP was studied by spectrophotometry. In a Britton-Robinson buffer solution at pH 2.9, tribromoarsenazo and bovine serum albumin can immediately form a red compound in the presence of emulgent OP with a maximum absorption wavelength at 354 nm. The presence of emulgent OP can increase the reaction sensitivity and the compound stability. The molar absorptivity of the compound is ε354 nm = 6.13 x 105 M-1•cm-1. Beer's law is obeyed over the range of 5.0-75.0 mg•L-1 for bovine serum albumin. The present method was applied to the determination of the total proteins in human serums with satisfactory results.

Biodistribution analysis of 125I-albumin-IFN-alpha2b fusion protein in rats

International Nuclear Information System (INIS)

Zhou Yaoyuan; Zhang Rongjun; Cai Gangming; Gu Xiaobo; Jiang Mengjun; Zhang Bo; Yang Min; Cao Guoxian; Yang Jianliang

2009-01-01

125 I-albumin-IFN-alpha2b was prepared with the methods of Ch-T and purified with PD-10 column. The radiochemical purity was measured with TCA (trichloroacetic acid) precipitation. The antiviral activities of 125 I-albumin-IFN-alpha2b and albumin-IFN-alpha2b were compared with WISH/VSV system in vitro. SD rats were injected with 125 I-albumin-IFN-alpha2b subcutaneously and sacrificed at 0.5, 2, 6, 24, 48, 90, 180 and 300 h post-injection. Selected organs were dissected, weighed and their radioactivity was measured using γ-counter. The accumulated radioactivity in the tissues was calculated in terms of percentage of injected dose per gram organ (%ID·g -1 ). The labeling yield was 82.72%. The radiochemical purity of 125 I-albumin-IFN-alpha2b was 95.53%, and its radioactivity was 0.26 MBq/μg. The antiviral bioactivities of albumin-IFN-alpha2b and 125 I-albumin- IFN-alpha2b did not change. Biodistribution analysis of 125 I-albumin-IFN-alpha2b in rats showed that concentrated 125 I-albumin-IFN-alpha2b in blood reached maximum at 6 h post injection, and eliminated slowly. No specific accumulation was seen in other tissues. 125 I-albumin-IFN-alpha2b could maintain in peripheral blood for a long time and it meant albumin-IFN-alpha2b would be an effective long-term interferon. (authors)

Identification of tissue sites for increased albumin degradation in sarcoma-bearing mice

International Nuclear Information System (INIS)

Andersson, C.; Iresjoe, B.M.L.; Lundholm, K.

1991-01-01

Plasma albumin concentration declines in both experimental and clinical cancer. Previous investigations have demonstrated that this is partly explained by increased breakdown of albumin. The present study has identified the tissue sites for increased albumin degradation in a nonmetastasizing sarcoma mouse (C57/BL6J) model. Results have been compared to nontumor-bearing animals either freely fed or food restricted (pair-weighed) so that their body composition was similar to tumor-bearing animals. Tumor-bearing mice had increased albumin degradation (0.13 +/- 0.02 mg/hr/g bw) compared to both freely fed (0.09 +/- 0.007) and pair-weighed control animals (0.05 +/- 0.008). Radioactivity from circulating [3H]raffine aldehyde labeled albumin appeared with maximum peak values in lysosomes isolated from both tumor and nontumor tissues at 48 hr following iv injection. The intralysosomal accumulation of radioactivity was two- to threefold higher in tumor tissue compared to liver tissue, although the specific activity of protease(s) for albumin degradation measured in vitro was not higher in tumor tissue (30.4 +/- 3.6 mg/hr/g tissue) compared to normal liver tissue (36.9 +/- 1.7). Accounting for the entire tumor the proteolytic capacity for albumin breakdown was however much larger in the tumor (161.6 +/- 32.6 mg/organ) compared to both normal liver (37.5 +/- 2.3) and tumor-host liver (56.4 +/- 2.8). Pepstatin inhibited 78 +/- 6% of the proteolytic activity in the tumor measured by 125I-labeled undenatured mouse albumin as the substrate. Leupeptin inhibited 49 +/- 6%. There was a significantly decreased breakdown of albumin in both skeletal muscles and the gastrointestinal tract from tumor-bearing animals

The effect of ionizing radiations on rat serum albumin on in vivo and in vitro

International Nuclear Information System (INIS)

Portakal, S.

1984-01-01

The effect of ionizing radiations on rat serum albumin was studied on in vivo and in vitro. Male rats (rattus norvegicus) were exposed to 225 roentgen wholebody X-irradiation on in vivo experiments. Time-course effects of irradiation on albumin level examined at immediately, 2.5 hours and 3 days after irradiation. Albumin level decreased above control level 2.5 hours after irradiation and rised within 3 days reaching control level. Pre-albumin/albumin ratio enhanced after x-irradiation. Aqueous solutions (0.5 percent) of rat serum albumin was exposed to various doses (0.2, 0.5, 1.0 and 1.9 Mrad) of 60 Co gamma irradiation on in vitro experiments. Results showed that electrophoretic mobility of serum albumin decreased after gamma irradiation. No significant change in albumin UV absorption spectrum was observed at 0.2, 0.5, 1.0 and 1.9 Mrad doses. Albumin becomes progressively less soluble in water as the radiation doses is increased. Radiation induced transformation into insoluble albumin agregates and scission products. (author)

Permeability-Porosity Relationships of Subduction Zone Sediments

Science.gov (United States)

Gamage, K.; Screaton, E.; Bekins, B.; Aiello, I.

2008-12-01

Permeability-porosity relationships for sediments from Northern Barbados, Costa Rica, Nankai, and Peru subduction zones were examined based on their sediment type and grain size distribution. Greater correlation was observed between permeability and porosity for siliciclastic sediments, diatom oozes, and nannofossil chalk than for nannofossil oozes. For siliciclastic sediments, grouping of sediments by clay content yields relationships that are generally consistent with results from other marine settings and suggest decreasing permeability for a given porosity as clay content increases. Correction of measured porosities for smectite content generally improves the quality of permeability-porosity relationships. The relationship between permeability and porosity for diatom oozes may be controlled by the amount of clay present in the ooze, causing diatom oozes to behave similarly to siliciclastic sediments. For a given porosity the nannofossil oozes have higher permeability values by 1.5 orders of magnitude than the siliciclastic sediments. However, the use of a permeability-porosity relation may not be appropriate for unconsolidated carbonates such as nannofossil oozes. This study provided insight to the effects of porosity correction for smectite, variations in lithology and grain size in permeability-porosity relationships. However, further progress in delineating controls on permeability will require more careful and better documented permeability tests on characterized samples.

Effect of phospholipid-based formulations of Boswellia serrata extract on the solubility, permeability, and absorption of the individual boswellic acid constituents present.

Science.gov (United States)

Hüsch, Jan; Gerbeth, Kathleen; Fricker, Gert; Setzer, Constanze; Zirkel, Jürgen; Rebmann, Herbert; Schubert-Zsilavecz, Manfred; Abdel-Tawab, Mona

2012-10-26

Boswellia serrata gum resin extracts are used widely for the treatment of inflammatory diseases. However, very low concentrations in the plasma and brain were observed for the boswellic acids (1-6, the active constituents of B. serrata). The present study investigated the effect of phospholipids alone and in combination with common co-surfactants (e.g., Tween 80, vitamin E-TPGS, pluronic f127) on the solubility of 1-6 in physiologically relevant media and on the permeability in the Caco-2 cell model. Because of the high lipophilicity of 1-6, the permeability experiments were adapted to physiological conditions using modified fasted state simulated intestinal fluid as apical (donor) medium and 4% bovine serum albumin in the basolateral (receiver) compartment. A formulation composed of extract/phospholipid/pluronic f127 (1:1:1 w/w/w) increased the solubility of 1-6 up to 54 times compared with the nonformulated extract and exhibited the highest mass net flux in the permeability tests. The oral administration of this formulation to rats (240 mg/kg) resulted in 26 and 14 times higher plasma levels for 11-keto-β-boswellic acid (1) and acetyl-11-keto-β-boswellic acid (2), respectively. In the brain, five times higher levels for 2 compared to the nonformulated extract were determined 8 h after oral administration.

Some human albumine metabolism aspects, gathered with the utilization of 131I-albumine in normal female individuals

International Nuclear Information System (INIS)

Cossermelli, W.; Papaleo Netto, M.; Carvalho, N.

1974-01-01

14 female individuals underwent a study of some aspects of the 131 I human albumine metabolism, by following-up the decreasing plasmatic radioactivity rate of this substance. The outcome of this study led to the following conclusions: the distribution hal-life presented an average and confidence interval of 15,40 +- -+ 2,16 hours; renovation half-life showed a median and confidence interval of 11,17 +- -+ 2,10 days; the renovation ratio presented an average and confidence interval of 6,80 +- -+ 1,31% days -1 . The conclusions hereabove allowed the authors to discuss the performance of these parameters upon the evaluation of the albumine synthesis and catabolism [pt

Gas and Water Permeability of Concrete

Energy Technology Data Exchange (ETDEWEB)

Villar, M. V.; Martin, P. L.; Romero, F. J.; Gutierrez-Rodirgo, V.; Barcala, J. M.

2012-11-01

The gas pressure of concrete samples was measured in an unsteady-state equipment working under low injection pressures and in a newly fine tuned steady-state setup working under different pressures. These measurements allowed the estimation of the intrinsic and relative gas permeability of the concrete and of the effect of boundary conditions on them. Permeability decreased with water content, but it was also greatly affected by the hydraulic history of concrete, i.e. if it had been previously dried or wetted. In particular, and for a given degree of saturation, the gas permeability of concrete previously saturated was lower than if the concrete had been just air dried or saturated after air drying. In any case, the gas permeability was about two orders of magnitude higher than the liquid water permeability (10-16 vs. 10-18 m2), probably due to the chemical reactions taking place during saturation (carbonation). The relative gas permeability of concrete increased sharply for water degrees of saturation smaller than 50%. The boundary conditions also affected the gas permeability, which seemed to be mostly conditioned by the back pressure and the confining pressure, increasing as the former increased and decreasing as the latter increased, i.e. decreasing as the effective pressure increased. Overall the increase of pressure head or injection pressure implied a decrease in gas permeability. External,microcracking during air-drying could not be ruled out as responsible for the decrease of permeability with confining pressure. The apparent permeability obtained applying the Klinkenberg method for a given effective pressure was only slightly smaller than the average of all the values measured for the same confining pressure range. For this reason it is considered that the Klinkenberg effect was not relevant in the range of pressures applied. (Author) 37 refs.

Structural changes during the unfolding of Bovine serum albumin

Indian Academy of Sciences (India)

The native form of serum albumin is the most important soluble protein in the body plasma. In order to investigate the structural changes of Bovine serum albumin (BSA) during its unfolding in the presence of urea, a small-angle neutron scattering (SANS) study was performed. The scattering curves of dilute solutions of BSA ...

Correlation between serum albumin, prealbumin and ventilator dependence in patients with COPD

Directory of Open Access Journals (Sweden)

Shu-Miao Wu

2016-04-01

Full Text Available Objective: To investigate the correlation between the serum albumin, prealbumin and ventilator dependence in patients with COPD. Methods: Serum albumin and prealbumin of 44 COPD patients using breathing machine>48 h were tested at admission, 1 week, 2 weeks treatment. According to the existence of ventilator dependence, divided the patients into the ventilator dependence group and the ventilator independence group, compare the albumin, prealbumin average of two groups, evaluate the correlation between the serum albumin, prealbumin and ventilator dependence in patients with COPD. Results: Albumin levels reduced in both groups after 1 week treatment, but there was no statistically significant difference. Albumin levels reduced in both groups after 2 weeks treatment, but more significantly in the ventilator dependence group, the difference had statistical significance. Prealbumin levels in the ventilator independence group after 1 week treatment didn’t reduced, but reduced in the ventilator dependence group, the difference was statistically significant. Prealbumin levels reduced in both groups after 2 weeks treatment, but more significant in the ventilator dependence group, the difference had statistical significance. Conclusion: Serum albumin and prealbumin levels were correlation with the ventilator dependence in patients with COPD. But prealbumin can more sensitively and more early predict the ventilator dependence in patients with COPD suffered from malnutrition.

Permeability of cork to gases.

Science.gov (United States)

Faria, David P; Fonseca, Ana L; Pereira, Helen; Teodoro, Orlando M N D

2011-04-27

The permeability of gases through uncompressed cork was investigated. More than 100 samples were assessed from different plank qualities to provide a picture of the permeability distribution. A novel technique based on a mass spectrometer leak detector was used to directly measure the helium flow through the central area of small disks 10 mm in diameter and 2 mm thick. The permeability for nitrogen, oxygen, and other gases was measured by the pressure rise technique. Boiled and nonboiled cork samples from different sections were evaluated. An asymmetric frequency distribution ranging 3 orders of magnitude (roughly from 1 to 1000 μmol/(cm·atm·day)) for selected samples without macroscopic defects was found, having a peak below 100 μmol/(cm·atm·day). Correlation was found between density and permeability: higher density samples tend to show lower permeability. However, boiled cork showed a mean lower permeability despite having a lower density. The transport mechanism of gases through cork was also examined. Calculations suggest that gases permeate uncompressed cork mainly through small channels between cells under a molecular flow regime. The diameter of such channels was estimated to be in the range of 100 nm, in agreement with the plasmodesmata size in the cork cell walls.

Human Albumin Improves Long-Term Behavioral Sequelae After Subarachnoid Hemorrhage Through Neurovascular Remodeling.

Science.gov (United States)

Xie, Yi; Liu, Wenhua; Zhang, Xiaohao; Wang, Liumin; Xu, Lili; Xiong, Yunyun; Yang, Lian; Sang, Hongfei; Ye, Ruidong; Liu, Xinfeng

2015-10-01

Subarachnoid hemorrhage results in significant long-lasting neurologic sequelae. Here, we investigated whether human albumin improves long-term outcomes in experimental subarachnoid hemorrhage and whether neurovascular remodeling is involved in the protection of albumin. Laboratory investigation. Hospital research laboratory. Male Sprague-Dawley rats. Rats underwent subarachnoid hemorrhage by endovascular perforation. Albumin of either 0.63 or 1.25 g/kg was injected IV immediately after the surgery. Modified Garcia test, beam-walking test, novel object recognition, and Morris water maze were employed to determine the behavioral deficits. The effects of albumin on early neurovascular dysfunction and chronic synaptic plasticity were also studied. Both doses of albumin significantly improved the sensorimotor scores (F = 31.277; p = 0.001) and cognitive performance (F = 7.982; p = 0.001 in novel object recognition test; and F = 3.431; p = 0.026 in the latency analysis of Morris water maze test) for at least 40 days after subarachnoid hemorrhage. There were remarkable microvasculature hypoperfusion, intracranial pressure rise, early vasoconstriction, neural apoptosis, and degeneration in subarachnoid hemorrhage rats, with albumin significantly attenuating such neurovascular dysfunction. Furthermore, albumin markedly prevented blood-brain barrier disruption, as indicated by less blood-brain barrier leakage, preserved blood-brain barrier-related proteins, and dampened gelatinase activities. The expressions of key synaptic elements were up-regulated with albumin supplementation in both acute and chronic phases. Accordingly, a higher dendritic spine density was observed in the prefrontal and hippocampal areas of albumin-treated subarachnoid hemorrhage animals. Albumin at low-to-moderate doses markedly improves long-term neurobehavioral sequelae after subarachnoid hemorrhage, which may involve an integrated process of neurovascular remodeling.

Interaction between toxic azo dye C.I. Acid Red 88 and serum albumins

International Nuclear Information System (INIS)

Naveenraj, Selvaraj; Solomon, Rajadurai Vijay; Venuvanalingam, Ponnambalam; Asiri, Abdullah M.; Anandan, Sambandam

2013-01-01

Serum albumin-toxic dye interaction studies will be of paramount importance in the field of toxicology due to its relation towards the distribution and transportation of dye in blood. In this regard, the binding between C.I. Acid Red 88 (AR88) and serum albumins (HSA and BSA) was investigated by using combination of spectroscopic and molecular modeling methods. The fluorescence results revealed that AR88 interact with serum albumins through the combination of static and dynamic quenching mechanism. The distance “r” between serum albumin and AR88 was obtained according to the Forster resonance energy transfer (FRET) theory. Synchronous fluorescence and CD spectral results showed alterations in the microenvironment and conformation of serum albumins. The molecular docking method is also employed to understand the interaction of AR88 with serum albumins. All these studies confirm that BSA has more affinity towards AR88 than that of HSA which suggests that AR88 is more easily transported in the body of bovid than human and so it is more hazardous to bovids. -- Highlights: • AR88 interacts with serum albumin through the combination of both static and dynamic quenching mechanism. • The binding site of AR88 in serum albumins is nearer to tryptophan moiety. • Circular Dichroism spectra showed that AR88 alters α-helicity of serum albumin. • This interaction study could be greatly imperative for further investigations in toxicology

Species dependence of [64Cu]Cu-Bis(thiosemicarbazone) radiopharmaceutical binding to serum albumins

International Nuclear Information System (INIS)

Basken, Nathan E.; Mathias, Carla J.; Lipka, Alexander E.; Green, Mark A.

2008-01-01

Introduction: Interactions of three copper(II) bis(thiosemicarbazone) positron emission tomography radiopharmaceuticals with human serum albumin, and the serum albumins of four additional mammalian species, were evaluated. Methods: 64 Cu-labeled diacetyl bis(N 4 -methylthiosemicarbazonato)copper(II) (Cu-ATSM), pyruvaldehyde bis(N 4 -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

Dynamics of albumin in plasma and ascitic fluid in patients with cirrhosis

DEFF Research Database (Denmark)

Henriksen, Jens Henrik; Siemssen, O; Krintel, J J

2001-01-01

BACKGROUND/AIMS: To determine dynamics of albumin in plasma and ascitic fluid of patients with cirrhosis. METHODS: Forty-seven patients were classified in four groups: I--patients without fluid retention; II--patients with ascites not resistant to subsequent diuretic treatment; III......--recompensated patients during diuretic treatment; and IV--patients with diuretic-resistant ascites. Transvascular and transperitoneal albumin transports were quantified by 131I-/125I-labelled human albumin. RESULTS: TER(P) (i.e. the fraction of intravascular albumin (IVM) passing from plasma into the interstitial space...... per hour) was increased in all groups. In group IV patients the transport rate of albumin from plasma into the ascitic fluid (TER(PA)) was significantly higher than the transport rate from the ascitic fluid back into the plasma: TER(AP) (0.45 vs. 0.26% IVM/h, P

Albumin administration prevents the onset of pressure ulcers in intensive care unit patients.

Science.gov (United States)

Serra, Raffaele; Grande, Raffaele; Buffone, Gianluca; Gallelli, Luca; Caroleo, Santo; Tropea, Francesco; Amantea, Bruno; de Franciscis, Stefano

2015-08-01

Pressure ulcers (PUs) are a common problem in critically ill patients admitted to the intensive care units (ICUs) and they account for more than 70% of patients with low serum albumin at admission. The aim of this study was to test the efficacy of intravenous administration of albumin in patients with low serum albumin albumin albumin for the first 3 days within the first week of ICU stay (group A) and 10 patients did not receive albumin (group B). Three patients (27·27%) showed the onset of PUs in group A, whereas seven patients (70%) showed the onset of PUs within the first 7 days of stay in group B. Moreover, ulcers of group B were more severe than those of group A. This study shows that intravenous administration of albumin reduces the onset of PUs in patients admitted to the ICU and in some cases it also reduces the risk of progression to advanced stages of PUs. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Thrombin stimulates albumin transcytosis in lung microvascular endothelial cells via activation of acid sphingomyelinase.

Science.gov (United States)

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. Copyright © 2016 the American Physiological Society.

Albumin Redhill (-1 Arg, 320 Ala → Thr): A glycoprotein variant of human serum albumin whose precursor has an aberrant signal peptidase cleavage site

International Nuclear Information System (INIS)

Brennan, S.O.; Myles, T.; Peach, R.J.; George, P.M.; Donaldson, D.

1990-01-01

Albumin Redhill is an electrophoretically slow genetic variant of human serum albumin that does not bind 63 Ni 2+ and has a molecular mass 2.5 kDa higher than normal albumin. Its inability to bind Ni 2+ was explained by the finding of an additional residue of Arg at position -1. This did not explain the molecular basis of the genetic variation or the increase in apparent molecular mass. Fractionation of tryptic digests on concanavalin A-Sepharose followed by peptide mapping of the bound and unbound fractions and sequence analysis of the glycopeptides identified a mutation of 320 Ala → Thr. This introduces as Asn-Tyr-Thr oligosaccharide attachment sequence centered on Asn-318 and explains the increase in molecular mass. This, however, did not satisfactorily explain the presence of the additional Arg residue at position -1. DNA sequencing of polymerase chain reaction-amplified genomic DNA encoding the prepro sequence of albumin indicated an additional mutation of -2 Arg → Cys. The authors propose that the new Phe-Cys-Arg sequence in the propeptide is an aberrant signal peptidase cleavage site and that the signal peptidase cleaves the propeptide of albumin Redhill in the lumen of the endoplasmic reticulum before it reaches the Golgi vesicles, the site of the diarginyl-specific proalbumin convertase

Relationship between urine albumin and endothelin in children with anaphylactoid purpura

International Nuclear Information System (INIS)

Duan Yongqiang; Chen Nianfa

2009-01-01

To study the function of urine albumin and endothelin (ET-1) in the occurrence and progress of ansphylactoid purura (HSP) and anaphylaxis purura nephritis (HSPN) in children, the serum level of ET-1 and urine albumin excretion rate in 29 children with HSP and 21 normal controls was detected by RIA and salicylic acid nephelometry respectively. The results showed that the content of urine albumin in 24 hours in HSP group has no significant difference compared with that of control group (P>0.05) , but the corresponding content in HSPN group has significant difference compared with that of control and HSP group (P<0.01). The serum ET-1 in HSP group has significant difference compared with control group (P<0.05), and the corresponding content in HSPN group has significant difference compared with control group and HSP group (P<0.01, P<0.05). The levels of urine albumin of 24 hours and serum ET-1 in HSPN group after treatment were decreased obviously compared with those before treatment (P<0.01). The content of urine albumin of 24 hours was positively correlated with serum levels of ET-1. The ET-1 participated the formation of HSP and HSPN, and was related to the occurrence and progress of urine albumin. (authors)

Clogging in permeable concrete: A review.

Science.gov (United States)

Kia, Alalea; Wong, Hong S; Cheeseman, Christopher R

2017-05-15

Permeable concrete (or "pervious concrete" in North America) is used to reduce local flooding in urban areas and is an important sustainable urban drainage system. However, permeable concrete exhibits reduction in permeability due to clogging by particulates, which severely limits service life. This paper reviews the clogging mechanism and current mitigating strategies in order to inform future research needs. The pore structure of permeable concrete and characteristics of flowing particulates influence clogging, which occurs when particles build-up and block connected porosity. Permeable concrete requires regular maintenance by vacuum sweeping and pressure washing, but the effectiveness and viability of these methods is questionable. The potential for clogging is related to the tortuosity of the connected porosity, with greater tortuosity resulting in increased potential for clogging. Research is required to develop permeable concrete that can be poured on-site, which produces a pore structure with significantly reduced tortuosity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Plasma disappearance of glycated and non-glycated albumin in type 1 (insulin-dependent) diabetes mellitus

DEFF Research Database (Denmark)

Bent-Hansen, L; Feldt-Rasmussen, B; Kverneland, Arne

1993-01-01

transport ratio) was determined from the disappearance data. The index was high in control subjects (1.021 +/- 0.0057 (SEM)). This reflects a mean difference between the two escape rates of 2.1% per hour (for comparison the mean of the fractional escape rate of non-glycated albumin of the normal control......The fractional plasma escape rates of glycated and non-glycated albumin have earlier been measured in groups of Type 1 (insulin-dependent) diabetic patients and control subjects. The escape of non-glycated albumin was similar in control subjects and normoalbuminuric patients, but elevated...... in patients with micro or macroalbuminuria. In all groups the escape rate of glycated albumin was lower than that of non-glycated albumin. Glycation increases the anionic charge of albumin. To assay for charge-dependent alterations of transport a selectivity index (non-glycated albumin/glycated albumin...

The intrarenal distribution of 125I-albumin in the syrian hamster

International Nuclear Information System (INIS)

Moeller, P.

1977-01-01

The intrarenal distribution of radioiodinated human serum albumin ( 125 RISA) after intravenous injection was studied in Syrian hamsters by scintillation counting and frozen section autoradiogrpahy. After 15, 30, and 60 min the virtual plasma albumin space in the renal cortex of the hamster represented 6.49, 7.13, and 8.06% respectively of the kidney tissue volume. From the cortex to the renal papilla the albumin space increased to about 30% of the tissue volume. In comparison to this the albumin space in the renal cortex of the rat was about 20%, and in the renal papilla about 33% (11). Frozen section autoradiography indicated that the distribution of radioalbumin in the renal cortex if the Syrian hamster is limited mainly to the kidney vessels, being especially noticeable in the glomerular capillaries. Toward the papilla increasingly greater (mainly extratubular) activity could be observed not only intravascularly but also interstitially. In the cortex of the rat kidney, on the other hand, radioactive albumin was accumulated (probably by filtration and reabsorption) predominantly in the proximal tubular epithelium. Within 30 min the kidneys of the rat excreted more than 10 times as much 125 I than the hamster kidneys. These results (substantially less cortical accumulation and urinary excretion of radioalbumin in the Syrian hamster) indicate that, in contrast to the rat, obviously much less albumin is filtered (and then accumulated by proximal reabsorption) by the Syrian hamster glomeruli. This suggests that the Syrian hamster kidney is more suitable than the rat kidney for determining the interstitial, cortical, albumin space. (orig./AJ) [de

Intravital Imaging Reveals Angiotensin II–Induced Transcytosis of Albumin by Podocytes

Science.gov (United States)

Schießl, Ina Maria; Hammer, Anna; Kattler, Veronika; Gess, Bernhard; Theilig, Franziska; Witzgall, Ralph

2016-01-01

Albuminuria is a hallmark of kidney disease of various etiologies and usually caused by deterioration of glomerular filtration barrier integrity. We recently showed that angiotensin II (Ang II) acutely increases albumin filtration in the healthy kidney. Here, we used intravital microscopy to assess the effects of Ang II on podocyte function in rats. Acute infusion of 30, 60, or 80 ng/kg per minute Ang II enhanced the endocytosis of albumin by activation of the type 1 Ang II receptor and resulted in an average (±SEM) of 3.7±2.2, 72.3±18.6 (Palbumin-containing vesicles per glomerulus, respectively, compared with none at baseline or 10 ng/kg per minute Ang II. Immunostaining of Ang II–infused kidneys confirmed the presence of albumin-containing vesicles, which colocalized with megalin, in podocin-positive cells. Furthermore, podocyte endocytosis of albumin was markedly reduced in the presence of gentamicin, a competitive inhibitor of megalin-dependent endocytosis. Ang II infusion increased the concentration of albumin in the subpodocyte space, a potential source for endocytic protein uptake, and gentamicin further increased this concentration. Some endocytic vesicles were acidified and colocalized with LysoTracker. Most vesicles migrated from the capillary to the apical aspect of the podocyte and were eventually released into the urinary space. This transcytosis accounted for approximately 10% of total albumin filtration. In summary, the transcellular transport of proteins across the podocyte constitutes a new pathway of glomerular protein filtration. Ang II enhances the endocytosis and transcytosis of plasma albumin by podocytes, which may eventually impair podocyte function. PMID:26116357

Albumin in Burn Shock Resuscitation: A Meta-Analysis of Controlled Clinical Studies.

Science.gov (United States)

Navickis, Roberta J; Greenhalgh, David G; Wilkes, Mahlon M

2016-01-01

Critical appraisal of outcomes after burn shock resuscitation with albumin has previously been restricted to small relatively old randomized trials, some with high risk of bias. Extensive recent data from nonrandomized studies assessing the use of albumin can potentially reduce bias and add precision. The objective of this meta-analysis was to determine the effect of burn shock resuscitation with albumin on mortality and morbidity in adult patients. Randomized and nonrandomized controlled clinical studies evaluating mortality and morbidity in adult patients receiving albumin for burn shock resuscitation were identified by multiple methods, including computer database searches and examination of journal contents and reference lists. Extracted data were quantitatively combined by random-effects meta-analysis. Four randomized and four nonrandomized studies with 688 total adult patients were included. Treatment effects did not differ significantly between the included randomized and nonrandomized studies. Albumin infusion during the first 24 hours showed no significant overall effect on mortality. However, significant statistical heterogeneity was present, which could be abolished by excluding two studies at high risk of bias. After those exclusions, albumin infusion was associated with reduced mortality. The pooled odds ratio was 0.34 with a 95% confidence interval of 0.19 to 0.58 (P Albumin administration was also accompanied by decreased occurrence of compartment syndrome (pooled odds ratio, 0.19; 95% confidence interval, 0.07-0.50; P albumin can improve outcomes of burn shock resuscitation. However, the scope and quality of current evidence are limited, and additional trials are needed.

Geothermal Permeability Enhancement - Final Report

Energy Technology Data Exchange (ETDEWEB)

Joe Beall; Mark Walters

2009-06-30

The overall objective is to apply known permeability enhancement techniques to reduce the number of wells needed and demonstrate the applicability of the techniques to other undeveloped or under-developed fields. The Enhanced Geothermal System (EGS) concept presented in this project enhances energy extraction from reduced permeability zones in the super-heated, vapor-dominated Aidlin Field of the The Geysers geothermal reservoir. Numerous geothermal reservoirs worldwide, over a wide temperature range, contain zones of low permeability which limit the development potential and the efficient recovery of heat from these reservoirs. Low permeability results from poorly connected fractures or the lack of fractures. The Enhanced Geothermal System concept presented here expands these technologies by applying and evaluating them in a systematic, integrated program.

Effect of Adsorbed Protein on the Hydraulic Permeability, Membrane and Streaming Potential Values Measured across a Microporous Membrane

DEFF Research Database (Denmark)

Benavente, Juana; Jonsson, Gunnar Eigil

1998-01-01

permeability decreases strongly when the pH decreases, having its minimum value at the isoelectric point of the protein; the apparent zeta potential values are also dependent on both pH and salt concentration. Differences in the streaming potential coefficient determined for two membranes fouled under......The effect of the adsorption of a protein, bovine serum albumin (BSA), on the membrane potential, flux reduction and streaming potential measured across a microporous polysulphone membrane with different NaCl solutions and pH values is studied. From electrokinetic phenomena, information about...... the electrical properties of the membrane (fixed charge concentration and ionic transport numbers) or the membrane/solute interactions (streaming and zeta potentials) can be obtained. The influence of pH and ionic strength on volume flux and streaming potential values is considered. Results show that hydraulic...

Release of proteins via ion exchange from albumin-heparin microspheres

NARCIS (Netherlands)

Kwon, Glen S.; Bae, You Han; Cremers, H.F.M.; Cremers, Harry; Feijen, Jan; Kim, Sung Wan

1992-01-01

Albumin-heparin and albumin microspheres were prepared as ion exchange gels for the controlled release of positively charged polypeptides and proteins. The adsorption isotherms of chicken egg and human lysozyme, as model proteins, on microspheres were obtained. An adsorption isotherm of chicken egg

A Reconciliation of Packed Column Permeability Data: Column Permeability as a Function of Particle Porosity

Directory of Open Access Journals (Sweden)

Hubert M. Quinn

2014-01-01

Full Text Available In his textbook teaching of packed bed permeability, Georges Guiochon uses mobile phase velocity as the fluid velocity term in his elaboration of the Darcy permeability equation. Although this velocity frame makes a lot of sense from a thermodynamic point of view, it is valid only with respect to permeability at a single theoretical boundary condition. In his more recent writings, however, Guiochon has departed from his long-standing mode of discussing permeability in terms of the Darcy equation and has embraced the well-known Kozeny-Blake equation. In this paper, his teaching pertaining to the constant in the Kozeny-Blake equation is examined and, as a result, a new correlation coefficient is identified and defined herein based on the velocity frame used in his teaching. This coefficient correlates pressure drop and fluid velocity as a function of particle porosity. We show that in their experimental protocols, Guiochon et al. have not adhered to a strict material balance of permeability which creates a mismatch of particle porosity and leads to erroneous conclusions regarding the value of the permeability coefficient in the Kozeny-Blake equation. By correcting the experimental data to properly reflect particle porosity we reconcile the experimental results of Guiochon and Giddings, resulting in a permeability reference chart which is presented here for the first time. This reference chart demonstrates that Guiochon’s experimental data, when properly normalized for particle porosity and other related discrepancies, corroborates the value of 267 for the constant in the Kozeny-Blake equation which was derived by Giddings in 1965.

Apparent loss of urinary albumin during long-term frozen storage : HPLC vs immunonephelometry

NARCIS (Netherlands)

Brinkman, Jacoline W.; De Zeeuw, Dick; Lambers Heerspink, Hiddo J.; Gansevoort, Ronald T.; Kema, Ido P.; de Jong, Paul E.; Bakker, Stephan J. L.

Background: Urinary albumin detection by immuno-nephelometry is decreased by -30% in samples that have been frozen at -20 degrees C. An HPLC method for assessment of urinary albumin that detects immunoreactive and immunochemically nonreactive albumin has been introduced as an alternative to

Crustal permeability: Introduction to the special issue

Science.gov (United States)

Ingebritsen, Steven E.; Gleeson, Tom

2015-01-01

The topic of crustal permeability is of broad interest in light of the controlling effect of permeability on diverse geologic processes and also timely in light of the practical challenges associated with emerging technologies such as hydraulic fracturing for oil and gas production (‘fracking’), enhanced geothermal systems, and geologic carbon sequestration. This special issue of Geofluids is also motivated by the historical dichotomy between the hydrogeologic concept of permeability as a static material property that exerts control on fluid flow and the perspective of economic geologists, geophysicists, and crustal petrologists who have long recognized permeability as a dynamic parameter that changes in response to tectonism, fluid production, and geochemical reactions. Issues associated with fracking, enhanced geothermal systems, and geologic carbon sequestration have already begun to promote a constructive dialog between the static and dynamic views of permeability, and here we have made a conscious effort to include both viewpoints. This special issue also focuses on the quantification of permeability, encompassing both direct measurement of permeability in the uppermost crust and inferential permeability estimates, mainly for the deeper crust.

In Vitro Effect of Lysozyme on Albumin Deposition to Hydrogel Contact Lens Materials.

Science.gov (United States)

Babaei Omali, Negar; Subbaraman, Lakshman N; Heynen, Miriam; Fadli, Zohra; Coles-Brennan, Chantal; Jones, Lyndon W

2017-11-01

Albumin deposition on contact lenses could be detrimental to contact lens (CL) wear because this may increase the risk of bacterial binding and reduce comfort. Lysozyme deposition on selected lens materials would reduce albumin deposition on lenses. This study aims to determine if lysozyme deposition on CLs could act as a barrier against subsequent albumin adsorption, using an in vitro model. Six hydrogel CL materials (etafilcon A, polymacon, nelfilcon A, omafilcon A, ocufilcon B, and nesofilcon A) were evaluated. Four CLs of each type were soaked in lysozyme solution for 16 hours at 37°C. Lysozyme-coated lenses were then placed in vials with 1.5 mL of artificial tear solution containing I-labeled albumin for 16 hours at 37°C with shaking. Four uncoated lenses of each type were used as controls. Lenses soaked in radiolabeled albumin were rinsed in a phosphate-buffered saline solution, and radioactive counts were measured directly on lenses using a gamma counter. Albumin uptake on lenses was measured using a calibration curve by plotting radioactive counts versus protein concentration. Results are reported as mean ± SD. Lysozyme-coated etafilcon A lenses exhibited lower levels of deposited albumin than uncoated etafilcon A lenses (58 ± 12 vs. 84 ± 5 ng/lens; P albumin adsorption between control (uncoated) and lysozyme-coated polymacon (105 ± 10 vs. 110 ± 34 ng/lens), nelfilcon A (51 ± 7 vs. 42 ± 20 ng/lens), omafilcon A (90 ± 20 vs. 80 ± 38 ng/lens), ocufilcon B (87 ± 20 vs. 115 ± 50 ng/lens), and nesofilcon A (170 ± 29 vs. 161 ± 10 ng/lens) lens materials (P > .05). Uncoated nesofilcon A lenses deposited the highest amount of albumin when compared with other uncoated lenses (P albumin, which may potentially be beneficial to CL wearers.

Methods of albumin estimation in clinical biochemistry: Past, present, and future.

Science.gov (United States)

Kumar, Deepak; Banerjee, Dibyajyoti

2017-06-01

Estimation of serum and urinary albumin is routinely performed in clinical biochemistry laboratories. In the past, precipitation-based methods were popular for estimation of human serum albumin (HSA). Currently, dye-binding or immunochemical methods are widely practiced. Each of these methods has its limitations. Research endeavors to overcome such limitations are on-going. The current trends in methodological aspects of albumin estimation guiding the field have not been reviewed. Therefore, it is the need of the hour to review several aspects of albumin estimation. The present review focuses on the modern trends of research from a conceptual point of view and gives an overview of recent developments to offer the readers a comprehensive understanding of the subject. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of serum albumin, analytical challenges: a French multicenter study.

Science.gov (United States)

Rossary, Adrien; Blondé-Cynober, Françoise; Bastard, Jean-Philippe; Beauvieux, Marie-Christine; Beyne, Pascale; Drai, Jocelyne; Lombard, Christine; Anglard, Ingrid; Aussel, Christian; Claeyssens, Sophie; Vasson, Marie-Paule

2017-06-01

Among the biological markers of morbidity and mortality, albumin holds a key place in the range of criteria used by the High Authority for Health (HAS) for the assessment of malnutrition and the coding of information system medicalization program (PMSI). If the principle of quantification methods have not changed in recent years, the dispersion of external evaluations of the quality (EEQ) data shows that the standardization using the certified reference material (CRM) 470 is not optimal. The aim of this multicenter study involving 7 sites, conducted by a working group of the French Society of Clinical Biology (SFBC), was to assess whether the albuminemia values depend on the analytical system used. The albumin from plasma (n=30) and serum (n=8) pools was quantified by 5 different methods [bromocresol green (VBC) and bromocresol purple (PBC) colorimetry, immunoturbidimetry (IT), immunonephelometry (IN) and capillary electrophoresis (CE)] using 12 analyzers. Bland and Altman's test evaluated the difference between the results obtained by the different methods. For example, a difference as high as 13 g/L was observed for the same sample between the methods (p albumin across the range of values tested compared to PBC (p albumin values inducing a difference of performance between the immunoprecipitation methods (IT vs IN, p albumin results are related to the technical/analyzer tandem used. This variability is usually not taken into account by the clinician. Thus, clinicians and biologists have to be aware and have to check, depending on the method used, the albumin thresholds identified as risk factors for complications related to malnutrition and PMSI coding.

Aging-associated oxidized albumin promotes cellular senescence and endothelial damage

Directory of Open Access Journals (Sweden)

Luna C

2016-02-01

Full Text Available Carlos Luna,1,* Matilde Alique,2,* Estefanía Navalmoral,2 Maria-Victoria Noci,3 Lourdes Bohorquez-Magro,2 Julia Carracedo,1 Rafael Ramírez2 1Nephrology Unit, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC, Reina Sofía University Hospital, Córdoba, Spain; 2Department of Systems Biology, Physiology Unit, Universidad de Alcalá, Madrid, Spain; 3Anesthesia Unit, Reina sofía University Hospital, Córdoba, Spain*These authors contributed equally to this work Abstract: 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.Keywords: elderly, oxidative stress, microparticles, vascular damage

Interactions of serum albumins with antitumor agent benzo [a] phenazine-a spectroscopic study

International Nuclear Information System (INIS)

Sivakumar, Radhakrishnan; Naveenraj, Selvaraj; Anandan, Sambandam

2011-01-01

We present an investigation on the site specific interaction of antitumor agent benzo [a] phenazine (BAP) with serum albumins (HSA and BSA) and related photo-physical properties using absorption, emission and lifetime measurements. The absorption and emission measurements reveal that the binding of biomolecule benzo [a] phenazine took place near tryptophan moiety present in sub-domain IIA in serum albumins (HSA and BSA). In the selective excitation of benzo [a] phenazine at 365 nm, it was observed that the ground state of serum albumin quenches the excited benzo [a] phenazine through charge transfer exciplexation. The fluorescence decay analysis of serum albumins in the presence of benzo [a] phenazine shows decrease in lifetime, which confirms that photo-induced electron transfer takes place from serum albumins (HSA and BSA) to BAP. Also a suitable mechanism was proposed for the observed photo-induced electron transfer processes. Binding average distance (r) between the donor (serum albumins) and acceptor (benzo [a] phenazine) calculated using FRET theory confirmed their high probability of binding interaction. - Graphical Abstract: Highlights: → Benzo [a] phenazine (BAP) specifically bounds with tryptophan present in HSA and BSA. → Ground state of serum albumin quenches the excited BAP at 365 nm. → Lifetime of serum albumins decreases in the presence of BAP. → Photo-induced electron transfer from HSA and BSA to BAP takes place.

Studies of 51Cr-albumin metabolism by the method of the whole body radiometry in men

International Nuclear Information System (INIS)

Bondarenko, N.I.; Kaplan, M.A.; Bolovin, L.M.

1980-01-01

A method of investigation on metabolism of human serum 61 Cr-labelled albumin is reported. The method allows to determine albumin and plasma losses without of collecting excreta. The studies of external losses show that healthy individuals lose about 2% or 2.5 g albumin and 60-70 ml plasma a day on the average. Total plasma albumin, extravascular albumin and total metabolic albumin are calculated by means of whole-body radiometry

Investigation of interactions between dendrimer-coated magnetite nanoparticles and bovine serum albumin

International Nuclear Information System (INIS)

Pan Bifeng; Gao Feng; Ao Limei

2005-01-01

We investigated the interactions between dendrimer-coated magnetite nanoparticles (MNPs) and the protein serum albumin. The investigation was based on the fluorescence quenching of tryptophan residue of serum albumin after binding with the dendrimer-coated magnetite nanoparticles. The extent of the interactions between bovine serum albumin and dendrimer-coated MNPs strongly depends on their surface groups and pH value

Radiation-induced Changes in the Electrophoretic Profile of Serum Albumin

Directory of Open Access Journals (Sweden)

Celso Vieira Lima

2018-01-01

Full Text Available ABSTRACT Albumin protein profiles were investigated in electrophoresis system in relation to the whole body exposition to the radiation. Two groups of rats Wistar were set up as the control (CG and the irradiated one (IG. The IG was exposed to Co-60 at a dose of 5 Gy. After a 72-hour exposition, 300 μL of blood was collected in the inferior vena cava, renal, jugular, hepatic, and pulmonary veins and the serum separated. The albumin protein was identified by vertical electrophoresis in acrylamide Commassi blue or silver stained. The calibration procedure was applied to albumin samples with well-known concentrations. The mathematical correlation was developed involving electrophoretic parameters of band intensities and sizes from gel representation, providing values of protein concentrations in comparison with standard bands with known concentrations. There were significant differences in the physiological concentrations in the jugular and pulmonary sites in relation to renal and cava regional sites. Significant differences induced by radiation in serum albumin concentration were also found in hepatic and jugular sites. Alteration of albumin concentration was found as a nearly effect from whole body irradiation. This phenomenon points out to alterations in cell metabolism in the liver justified by a possible indication of proteomics damage from radiation.

Effect of temperature on sandstone permeability

DEFF Research Database (Denmark)

Rosenbrand, Esther; Kjøller, Claus

Hot water injection in geothermal sandstone aquifers is considered for seasonal energy storage in Denmark. However, an increase in the aquifer temperature might reduce permeability, and thereby increase production costs. An understanding of the factors that control permeability is required in order...... and the Klinkenberg procedure showed the expected correlation between the two measures, however, differences could be around one order of magnitude. In tight gas sandstones, permeability is often sensitive to net stress, which might change due to the pore pressure change in the Klinkenberg procedure. Besides...... affecting the Klinkenberg procedure, the combined effect of slip and changes in permeability would affect production during pressure depletion in tight gas sandstone reservoirs; therefore effects of gas slip and net stress on permeability were combined in a model based on the Klinkenberg equation. A lower...

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

Directory of Open Access Journals (Sweden)

Shane A Liddelow

Full Text Available 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

Determination of albumin transport rate between plasma and peritoneal space in decompensated cirrhosis

DEFF Research Database (Denmark)

Ring-Larsen, H; Henriksen, Jens Henrik Sahl

1984-01-01

Plasma-to-peritoneal transport rate of albumin (TERperit.space) was determined in eighteen patients with decompensated cirrhosis by sampling ascitic fluid after i.v. injection of 125I-labelled serum albumin. Median TERperit.space was 0.30% of the intravascular albumin mass (IVM) per hour (range 0...

Increased transcapillary escape rate of albumin in patients with cirrhosis of the liver

DEFF Research Database (Denmark)

Parving, H H; Ranek, L; Lassen, N A

1977-01-01

The transcapillary escape rate of albumin (TERalb), i.e. the fraction of intravascular mass of albumin that passes to the extravascular space per unit time, was determined from the disappearance of intravenously injected 125I-labelled human serum albumin during the first 60 min after injection...... in nine patients with cirrhosis of the liver. Six of the patients had ascites. The wedged hepatic venous pressure or splenic pulp pressure ranged from 20 to 30 mmHg, mean 26 mmHg. Plasma albumin concentration was low, but plasma volume was slightly enlarged, and thus the intravascular mass of albumin...... was only moderately reduced. The transcapillary escape rate of albumin was significantly elevated in all the cirrhotics, mean 10.2%/h, range 8.8 to 12.3%/h, in comparison to values for twenty-eight normal subjects 5.4%/h, range 3.5-7.2%/h. Our results can best be explained by increased filtration out...

Intravital Imaging Reveals Angiotensin II-Induced Transcytosis of Albumin by Podocytes.

Science.gov (United States)

Schießl, Ina Maria; Hammer, Anna; Kattler, Veronika; Gess, Bernhard; Theilig, Franziska; Witzgall, Ralph; Castrop, Hayo

2016-03-01

Albuminuria is a hallmark of kidney disease of various etiologies and usually caused by deterioration of glomerular filtration barrier integrity. We recently showed that angiotensin II (Ang II) acutely increases albumin filtration in the healthy kidney. Here, we used intravital microscopy to assess the effects of Ang II on podocyte function in rats. Acute infusion of 30, 60, or 80 ng/kg per minute Ang II enhanced the endocytosis of albumin by activation of the type 1 Ang II receptor and resulted in an average (±SEM) of 3.7±2.2, 72.3±18.6 (Palbumin-containing vesicles per glomerulus, respectively, compared with none at baseline or 10 ng/kg per minute Ang II. Immunostaining of Ang II-infused kidneys confirmed the presence of albumin-containing vesicles, which colocalized with megalin, in podocin-positive cells. Furthermore, podocyte endocytosis of albumin was markedly reduced in the presence of gentamicin, a competitive inhibitor of megalin-dependent endocytosis. Ang II infusion increased the concentration of albumin in the subpodocyte space, a potential source for endocytic protein uptake, and gentamicin further increased this concentration. Some endocytic vesicles were acidified and colocalized with LysoTracker. Most vesicles migrated from the capillary to the apical aspect of the podocyte and were eventually released into the urinary space. This transcytosis accounted for approximately 10% of total albumin filtration. In summary, the transcellular transport of proteins across the podocyte constitutes a new pathway of glomerular protein filtration. Ang II enhances the endocytosis and transcytosis of plasma albumin by podocytes, which may eventually impair podocyte function. Copyright © 2016 by the American Society of Nephrology.

Dynamics of albumin synthetic response to intra-abdominal abscess in patients with gastrointestinal fistula.

Science.gov (United States)

Zhou, Bo; Ren, Jianan; Han, Gang; Chen, Yu; A, Jiye; Gu, Guosheng; Chen, Jun; Wang, Gefei; Li, Jieshou

2014-04-01

Low serum albumin concentration is a predictor of failure of source control for intra-abdominal infection. However, data on dynamics of albumin synthesis in these patients and to what extent these changes contribute to hypoalbuminemia are relatively scarce. We investigated in a group of patients with gastrointestinal fistula the dynamic response of liver albumin synthesis to intra-abdominal abscess and how these related to hypoalbuminemia and circulating endocrine hormone profiles. Eight gastrointestinal fistula patients scheduled to undergo percutaneous abscess sump drainage were enrolled prospectively to measure albumin synthesis rates at different stages of the inflammatory response (immediately after diagnosis and 7 d following sump drainage when clinical signs of intra-abdominal sepsis had been eradicated). Eight age-, sex-, and body mass index-matched intestinal fistula patients were studied as control patients. Consecutive arterial blood samples were drawn during a primed-constant infusion (priming dose: 4 micromol·kg(-1), infusion rate: 6 micromol·kg(-1)·min(-1)) to determine the incorporation rate of L-[ring-(2)H5]-phenylalanine directly into plasma albumin using gas chromatography/mass spectrometry analysis. Patients suffering from intra-abdominal infection had reduced plasma albumin and total plasma protein concentrations, compared with control patients. Albumin fractional synthesis rates in patients with intra-abdominal abscess were decreased, compared with those in the control group. When the source of infection was removed, albumin synthesis rates returned to control values, whereas albumin concentrations did not differ significantly from the corresponding concentrations in control subjects and patients with intra-abdominal abscess. Despite nutritional intervention, albumin synthesis rate is decreased in intestinal fistula patients with intra-abdominal abscess; albumin synthesis returns to control values during convalescence.

Fluorescent holograms with albumin-acrylamide

Science.gov (United States)

Ordóñez-Padilla, M. J.; Olivares-Pérez, A.; Fuentes-Tapia, I.

2014-02-01

We describe fluorescent holograms were made with photosensitive films of albumin (protein) quail, used as modified matrices. Albumin is mixed with acrylamide and eosin Y. Therefore, prepare a photosensitive emulsion and solid hydrated with the ability to phase transmission holograms and volume (VPH). Eosin Y is a fluorescent agent that acts as a photo-sensitizing dye which stimulates the polymerization of acrylamide. To record the interference pattern produced by two waves superimposed on the modified matrix, we use a He-Cd laser. To reconstruct the diffraction pattern is observed with He- Ne laser, λ = 632.8nm, the material is self-developing properties. Measure the diffraction efficiency of the diffracted orders (η[-1, +1]) as a function of exposure energy. We work with various thicknesses and measure the variation of the refractive index using the coupled wave theory of Kogelnik, the holographic gratings meet Bragg condition.

Mature forms of the major seed storage albumins in sunflower: A mass spectrometric approach.

Science.gov (United States)

Franke, Bastian; Colgrave, Michelle L; Mylne, Joshua S; Rosengren, K Johan

2016-09-16

Seed storage albumins are abundant, water-soluble proteins that are degraded to provide critical nutrients for the germinating seedling. It has been established that the sunflower albumins encoded by SEED STORAGE ALBUMIN 2 (SESA2), SESA20 and SESA3 are the major components of the albumin-rich fraction of the common sunflower Helianthus annuus. To determine the structure of sunflowers most important albumins we performed a detailed chromatographic and mass spectrometric characterization to assess what post-translational processing they receive prior to deposition in the protein storage vacuole. We found that SESA2 and SESA20 each encode two albumins. The first of the two SESA2 albumins (SESA2-1) exists as a monomer of 116 or 117 residues, differing by a threonine at the C-terminus. The second of the two SESA2 albumins (SESA2-2) is a monomer of 128 residues. SESA20 encodes the albumin SESA20-2, which is a 127-residue monomer, whereas SESA20-1 was not abundant enough to be structurally described. SESA3, which has been partly characterized previously, was found in several forms with methylation of its asparagine residues. In contrast to other dicot albumins, which are generally matured into a heterodimer, all the dominant mature sunflower albumins SESA2, SESA20-2, SESA3 and its post-translationally modified analogue SESA3-a are monomeric. Sunflower plants have been bred to thrive in various climate zones making them favored crops to meet the growing worldwide demand by humans for protein. The abundance of seed storage proteins makes them an important source of protein for animal and human nutrition. This study explores the structures of the dominant sunflower napin-type seed storage albumins to understand what structures evolution has favored in the most abundant proteins in sunflower seed. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Changes in serum albumin conformation under the effect of UV-radiation

Energy Technology Data Exchange (ETDEWEB)

Stepuro, I I; Artsukevich, A N; Ostrovskij, Yu N [AN Belorusskoj SSR, Minsk

1981-01-01

It has been established that a rapid photolysis of one (the most libile) disulfide bridge in bull serum albumins (BSA) and man's serum albumins (MSA) is caused by the sensitizing effect of 212 and 214 triptophan residues respectively; in fact the residues decompose simultaneously with the destruction of disulfide bond. This effect is not observed in 6-8 M guanosine. Conformation rebuilding of albumin globule is observed after the destruction of disulfide bond in albumin by UV-radiation and sodium boron hydride; it is accompanied by the decrease of accessible for fluorescent probe arginine residues, the accessibility of lysine residues being unchanged. Probe fluorescent intensity - 1.8-anilinonaphthalenesulfonate - decreases after the reduction of disulfide bond by 60-70% due to the loss of accessibility for chromophore of arginine residues.

Changes in serum albumin conformation under the effect of UV-radiation

International Nuclear Information System (INIS)

Stepuro, I.I.; Artsukevich, A.N.; Ostrovskij, Yu.N.

1981-01-01

It has been established that a rapid photolysis of one (the most libile) disulfide bridge in bull serum albumins (BSA) and man's serum albumins (MSA) is caused by the sensitizing effect of 212 and 214 triptophan residues respectively; in fact the residues decompose simultaneously with the destruction of disulfide bond. This effect is not observed in 6-8 M guanosine. Conformation rebuilding of albumin globule is observed after the destruction of disulfide bond in albumin by UV-radiation and sodium boron hydride; it is accompanied by the decrease of accessible for fluorescent probe arginine residues, the accessibility of lysine residues being unchanged. Probe fluorescent intensity - 1.8-anilinonaphthalenesulfonate - decreases after the reduction of disulfide bond by 60-70% due to the loss of accessibility for chromophore of arginine residues

Serum albumin coating of demineralized bone matrix results in stronger new bone formation.

Science.gov (United States)

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. © 2015 Wiley Periodicals, Inc.

Overestimation of Albumin Measured by Bromocresol Green vs Bromocresol Purple Method: Influence of Acute-Phase Globulins.

Science.gov (United States)

Garcia Moreira, Vanessa; Beridze Vaktangova, Nana; Martinez Gago, Maria Dolores; Laborda Gonzalez, Belen; Garcia Alonso, Sara; Fernandez Rodriguez, Eloy

2018-05-22

Usually serum albumin is measured with dye-binding assay as bromocresol green (BCG) and bromocresol purple (BCP) methods. The aim of this paper was to examine the differences in albumin measurements between the Advia2400 BCG method (AlbBCG), Dimension RxL BCP (AlbBCP) and capillary zone electrophoresis (CZE). Albumin concentrations from 165 serum samples were analysed using AlbBCG, AlbBCP and CZE. CZE was employed to estimate different serum protein fractions. Influence of globulins on albumin concentration discrepancies between methods was estimated as well as the impact of the albumin method on aCa concentrations. Medcalc was employed for statistical analysis, setting a value of P albumin concentrations. AlbBCG were positively biased versus CZE (3.54 g/L). There was good agreement between CZE and ALbBCP (Albumin results from the BCP and BCG methods may result in unacceptable differences and clinical confusion, especially at lower albumin concentrations. Serum acute phase proteins contribute to overestimating the albumin concentration using AlbBCG.

Ex vivo instability of glycated albumin: A role for autoxidative glycation.

Science.gov (United States)

Jeffs, Joshua W; Ferdosi, Shadi; Yassine, Hussein N; Borges, Chad R

2017-09-01

Ex vivo protein modifications occur within plasma and serum (P/S) samples due to prolonged exposure to the thawed state-which includes temperatures above -30 °C. Herein, the ex vivo glycation of human serum albumin from healthy and diabetic subjects was monitored in P/S samples stored for hours to months at -80 °C, -20 °C, and room temperature, as well as in samples subjected to multiple freeze-thaw cycles, incubated at different surface area-to-volume ratios or under different atmospheric compositions. A simple dilute-and-shoot method utilizing trap-and-elute LC-ESI-MS was employed to determine the relative abundances of the glycated forms of albumin-including forms of albumin bearing more than one glucose molecule. Significant increases in glycated albumin were found to occur within hours at room temperature, and within days at -20 °C. These increases continued over a period of 1-2 weeks at room temperature and over 200 days at -20 °C, ultimately resulting in a doubling of glycated albumin in both healthy and diabetic patients. It was also shown that samples stored at lower surface area-to-volume ratios or incubated under a nitrogen atmosphere experienced less rapid glucose adduction of albumin-suggesting a role for oxidative glycation in the ex vivo glycation of albumin. Copyright © 2017 Elsevier Inc. All rights reserved.

Recovery And Valorization Of Snakehead Fish Channa Striata Surimi Wash Water As Stock Albumin Tablet

Directory of Open Access Journals (Sweden)

Ikbal Syukroni

2017-11-01

Full Text Available Surimi washing process is aimed to concentrate the myofibril protein by removing catepsin enzyme fat pigment blood and sarcoplasmic protein which is soluble in wash water. The soluble subtances cause trouble environment if it was untreated. In addition recovery protein will give benefit both in reducing trouble environment and utilizing soluble protein as sources of albumin protein. The objectives of research were to recover albumin from snakehead fish surimi wash water and to valorize as stock albumin tablet. Recovery of albumin use 0.05 m ultrafiltration membrane and the valorization of albumin tablets was by direct compression. The protein band with molecular weight of 67.741 kDa on the retentate was detected as albumin. Concentration of protein recover by ultrafiltration membrane increased 89.98 and the albumin content 3.50.4 gdl. Based on the result of chemical composition and microbiology analysis albumin of snakehead surimi wash water appropriate with Indonesia National Standard SNI quality requirement about snakehead fish albumin extract. The best formulation in the preparation of surimi wash water albumin tablet was by using corn starch excipients with uniformity weight value 410.39 0.09 g hardness value 7.65 0.8 Kp uniformity size of tablet with diameter 1 cm and thickness 0.59 cm friability value 2.3 and disintregation time of the tablet is 2 minutes 16 second.

An experimental study on MRI signal intensity of albumin solution

International Nuclear Information System (INIS)

Ahn, In Oak; Chang, Kee Hyun; Han, Moon Hee; Song, Chi Sung; Yeon, Kyung Mo

1990-01-01

This in vitro study attempted to correlate magnetic resonance (MR) signal intensity with concentration of albumin solution in magnetic field strength of 2.0 Tesla (T) and 0.5T. MR imaging of bovine serum albumin solutions of various concentrations ranging from 0 to 40 g/dl was performed on both 2.0T and 0.5T MR units. The relative (with respect to normal saline) signal intensities of each albumin solution were measured in T1-weighted, proton density-weighted and T2-weighted MR images, correlated with albumin concentration on each pulse sequence, and compared between 2.0T and 0.5T. Additionally, the albumin concentrations showing signal intensities identical to those of white matter, cortical gray matter and cerebrospinal fluid (CSF) of normal brain MRI were determined by visual comparison of those images. 1. On T1-weighted (SE 400-500 msec/30 msec) images under 2.0T and 0.5T field strength, the signal intensity increased with increasing albumin concentrations up to about 30-35 g/dl and the decreased. For the solutions ranging from 0 to about 5 g/dl concentration, the signal intensities appeared isointense to normal saline on visual inspection. 2. On proton density-weighted (SE 2000-2500 msec/30 msec) images under 2.0T and 0.5T field strength, the signal intensity slightly increased with increasing albumin concentrations up to about 7.5-10 g/dl, and then gradually decreased. 3. On T2-weighted (SE 2000-2500 msec/80-100 msec) images under 2.0T and 0.5T field strength, the signal intensity slightly increased with increasing albumin concentrations up to about 7.5-10 g/dl, and then gradually decreased. Above the concentration of about 25-30 g/dl, the signal intensity appeared lower than that of normal saline on visual inspection. 4. Compared with the signal intensities of normal brain structures on T1-weighted images under 2.0T and 0.5T field strength, the signal intensities of the albumin solution below 2.5-5 g/dl concentration were similar to that of CSF, and those of

Albumin profile of snakehead fish (Channastriata) from East Kalimantan, Indonesia

Science.gov (United States)

Asikin, A. N.; Kusumaningrum, I.

2018-04-01

This study aimed to determine the properties of albumin of snakehead fish (Channastrata) by various method extraction. The extraction of snakehead fish albumin was done using water (W), NaCl 0,9% (N), HCl 0.1 M (H). This research used three groups weight of snakehead that were 300-600 g (small; S), 600-900 g (medium; M) and 900-1200 g (large; L). Raw materials (snakehead fish) obtained from Middle Mahakam area, East Kalimantan, Indonesia. The parameters of this research were yield, proximate, albumin, and colour. The data were analyzed by using completely randomized design which consist two factors of treatments (solvent and weight of snakehead) and three replications.

Albumin-Bilirubin and Platelet-Albumin-Bilirubin Grades Accurately Predict Overall Survival in High-Risk Patients Undergoing Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma.

Science.gov (United States)

Hansmann, Jan; Evers, Maximilian J; Bui, James T; Lokken, R Peter; Lipnik, Andrew J; Gaba, Ron C; Ray, Charles E

2017-09-01

To evaluate albumin-bilirubin (ALBI) and platelet-albumin-bilirubin (PALBI) grades in predicting overall survival in high-risk patients undergoing conventional transarterial chemoembolization for hepatocellular carcinoma (HCC). This single-center retrospective study included 180 high-risk patients (142 men, 59 y ± 9) between April 2007 and January 2015. Patients were considered high-risk based on laboratory abnormalities before the procedure (bilirubin > 2.0 mg/dL, albumin 1.2 mg/dL); presence of ascites, encephalopathy, portal vein thrombus, or transjugular intrahepatic portosystemic shunt; or Model for End-Stage Liver Disease score > 15. Serum albumin, bilirubin, and platelet values were used to determine ALBI and PALBI grades. Overall survival was stratified by ALBI and PALBI grades with substratification by Child-Pugh class (CPC) and Barcelona Liver Clinic Cancer (BCLC) stage using Kaplan-Meier analysis. C-index was used to determine discriminatory ability and survival prediction accuracy. Median survival for 79 ALBI grade 2 patients and 101 ALBI grade 3 patients was 20.3 and 10.7 months, respectively (P  .05). ALBI and PALBI grades are accurate survival metrics in high-risk patients undergoing conventional transarterial chemoembolization for HCC. Use of these scores allows for more refined survival stratification within CPC and BCLC stage. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

Increased transcapillary escape rate of albumin and IgG in essential hypertension

DEFF Research Database (Denmark)

Parving, H H; Jensen, H A; Westrup, M

1977-01-01

Transcapillary escape rates of albumin and IgG (fractions of intravascular mass of albumin and IgG that pass to the extravascular space per unit time) were determined simultaneously from the initial disappearance of intravenously injected 131I human albumin and 125I human IgG in seven untreated...... subjects suffering from essential hypertension. The average mean arterial blood pressure of these subjects 193/119 mmHg; four subjects had grade I-III funduscopic changes. Transcapillary escape rates of albumin (TERalb) and IgG (TERIgG) were found significantly increased in the hypertensive subjects......, average 7.8 +/- 0.9 (SD) and 4.7 +/- 1.0 (SD) %/h, respectively, compared with normal values of mean 5.2 +/- 1.0 (SD) and 3.0 +/- 0.7 (SD) %/h, respectively (P less than 0.01). There was a statistically significant positive correlation between the mean arterial blood pressure and TER of albumin and of Ig...

Interaction of indomethacin with adult human albumin and neonatal serum

DEFF Research Database (Denmark)

Honoré, B; Brodersen, R; Robertson, A

1983-01-01

The binding of indomethacin to albumin was investigated at 37 degrees C, pH 7.4. The first stoichiometric binding constant is 2.5 X 10(5) M-1. Indomethacin utilizes both the bilirubin and diazepam binding functions equally. The effect on bilirubin binding to albumin is negligible at therapeutic...

Endocytosis of Albumin by Podocytes Elicits an Inflammatory Response and Induces Apoptotic Cell Death

Science.gov (United States)

Okamura, Kayo; Dummer, Patrick; Kopp, Jeffrey; Qiu, Liru; Levi, Moshe; Faubel, Sarah; Blaine, Judith

2013-01-01

The presence of albuminuria is strongly associated with progression of chronic kidney disease. While albuminuria has been shown to injure renal proximal tubular cells, the effects of albumin on podocytes have been less well studied. We have addressed the hypothesis that exposure of podocytes to albumin initiates an injury response. We studied transformed human-urine derived podocytes-like epithelial cells (HUPECS, or podocytes). Upon differentiation, these cells retain certain characteristics of differentiated podocytes, including expression of synaptopodin, CD2AP, and nestin. We exposed podocytes to recombinant human albumin, which lacks lipids and proteins that bind serum albumin; this reagent allowed a direct examination of the effects of albumin. Podocytes endocytosed fluoresceinated albumin and this process was inhibited at 4°C, suggesting an energy-dependent process. Exposure to albumin at concentrations of 5 and 10 mg/ml was associated with increased cell death in a dose-dependent manner. The mechanism of cell death may involve apoptosis, as caspase 3/7 were activated and the pan-caspase inhibitor z-VAD reduced cell death. Albumin exposure also increased nuclear factor (NF)-κB activation and increased transcription and release of interleukin (IL-) 1β, tumor necrosis factor (TNF), and IL-6. We extended these findings to an in vivo model. Glomeruli isolated from mice with nephrotic syndrome also had increased expression of IL-1β and TNF RNA. These data suggest that while podocyte injury begets albuminuria, albumin in the glomerular ultrafiltrate may also beget podocyte injury. Thus, an additional mechanism by which anti-proteinuric therapies are beneficial in the treatment of glomerular diseases may be a reduction in injury to the podocyte by albumin. PMID:23382978

Species dependence of [{sup 64}Cu]Cu-Bis(thiosemicarbazone) radiopharmaceutical binding to serum albumins

Energy Technology Data Exchange (ETDEWEB)

Basken, Nathan E. [Division of Nuclear Pharmacy, Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, IN 47907 (United States)], E-mail: nbasken@purdue.edu; Mathias, Carla J. [Division of Nuclear Pharmacy, Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, IN 47907 (United States); Lipka, Alexander E. [Department of Statistics, Purdue University, West Lafayette, IN 47907 (United States); Green, Mark A. [Division of Nuclear Pharmacy, Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, IN 47907 (United States)], E-mail: magreen@purdue.edu

2008-04-15

Introduction: Interactions of three copper(II) bis(thiosemicarbazone) positron emission tomography radiopharmaceuticals with human serum albumin, and the serum albumins of four additional mammalian species, were evaluated. Methods: {sup 64}Cu-labeled diacetyl bis(N{sup 4}-methylthiosemicarbazonato)copper(II) (Cu-ATSM), pyruvaldehyde bis(N{sup 4}-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.

Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

Energy Technology Data Exchange (ETDEWEB)

Alves, Vinicius M. [Laboratory of Molecular Modeling and Design, Faculty of Pharmacy, Federal University of Goiás, Goiânia, GO 74605-220 (Brazil); Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States); Muratov, Eugene [Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States); Laboratory of Theoretical Chemistry, A.V. Bogatsky Physical–Chemical Institute NAS of Ukraine, Odessa 65080 (Ukraine); Fourches, Denis [Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States); Strickland, Judy; Kleinstreuer, Nicole [ILS/Contractor supporting the NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM), P.O. Box 13501, Research Triangle Park, NC 27709 (United States); Andrade, Carolina H. [Laboratory of Molecular Modeling and Design, Faculty of Pharmacy, Federal University of Goiás, Goiânia, GO 74605-220 (Brazil); Tropsha, Alexander, E-mail: alex_tropsha@unc.edu [Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States)

2015-04-15

Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R{sup 2} = 0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q{sup 2}{sub ext} = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. - Highlights: • It was compiled the largest publicly-available skin permeability dataset. • Predictive QSAR models were developed for skin permeability. • No concordance between skin

Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

International Nuclear Information System (INIS)

Alves, Vinicius M.; Muratov, Eugene; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

2015-01-01

Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R 2 = 0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q 2 ext = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. - Highlights: • It was compiled the largest publicly-available skin permeability dataset. • Predictive QSAR models were developed for skin permeability. • No concordance between skin sensitization and

Effects of non-enzymatic glycation in human serum albumin. Spectroscopic analysis

Science.gov (United States)

Szkudlarek, A.; Sułkowska, A.; Maciążek-Jurczyk, M.; Chudzik, M.; Równicka-Zubik, J.

2016-01-01

Human serum albumin (HSA), transporting protein, is exposed during its life to numerous factors that cause its functions become impaired. One of the basic factors - glycation of HSA - occurs in diabetes and may affect HSA-drug binding. Accumulation of advanced glycation end-products (AGEs) leads to diseases e.g. diabetic and non-diabetic cardiovascular diseases, Alzheimer disease, renal disfunction and in normal aging. The aim of the present work was to estimate how non-enzymatic glycation of human serum albumin altered its tertiary structure using fluorescence technique. We compared glycated human serum albumin by glucose (gHSAGLC) with HSA glycated by fructose (gHSAFRC). We focused on presenting the differences between gHSAFRC and nonglycated (HSA) albumin used acrylamide (Ac), potassium iodide (KI) and 2-(p-toluidino)naphthalene-6-sulfonic acid (TNS). Changes of the microenvironment around the tryptophan residue (Trp-214) of non-glycated and glycated proteins was investigated by the red-edge excitation shift method. Effect of glycation on ligand binding was examined by the binding of phenylbutazone (PHB) and ketoprofen (KP), which a primary high affinity binding site in serum albumin is subdomain IIA and IIIA, respectively. At an excitation and an emission wavelength of λex 335 nm and λem 420 nm, respectively the increase of fluorescence intensity and the blue-shift of maximum fluorescence was observed. It indicates that the glycation products decreases the polarity microenvironment around the fluorophores. Analysis of red-edge excitation shift method showed that the red-shift for gHSAFRC is higher than for HSA. Non-enzymatic glycation also caused, that the Trp residue of gHSAFRC becomes less accessible for the negatively charged quencher (I-), KSV value is smaller for gHSAFRC than for HSA. TNS fluorescent measurement demonstrated the decrease of hydrophobicity in the glycated albumin. KSV constants for gHSA-PHB systems are higher than for the unmodified serum

Albumin-based drug delivery: harnessing nature to cure disease.

Science.gov (United States)

Larsen, Maja Thim; Kuhlmann, Matthias; Hvam, Michael Lykke; Howard, Kenneth A

2016-01-01

The effectiveness of a drug is dependent on accumulation at the site of action at therapeutic levels, however, challenges such as rapid renal clearance, degradation or non-specific accumulation requires drug delivery enabling technologies. Albumin is a natural transport protein with multiple ligand binding sites, cellular receptor engagement, and a long circulatory half-life due to interaction with the recycling neonatal Fc receptor. Exploitation of these properties promotes albumin as an attractive candidate for half-life extension and targeted intracellular delivery of drugs attached by covalent conjugation, genetic fusions, association or ligand-mediated association. This review will give an overview of albumin-based products with focus on the natural biological properties and molecular interactions that can be harnessed for the design of a next-generation drug delivery platform.

Clearance of 99mTc-labeled albumin from lungs in anesthetized guinea pigs

International Nuclear Information System (INIS)

Connelly, J.C.; Peterson, B.T.

1993-01-01

Gamma imaging was used to measure the rate of clearance of aerosolized 99m Tc-human serum albumin (HSA) from the lungs of control guinea pigs and guinea pigs that received increased lung inflation or lung injury. Anesthetized guinea pigs were ventilated for 6 min with an aerosol of HSA and the radioactivity in the chest was monitored for 2 h with a gamma camera to determine whether the clearance rate would be a reliable assessment of lung epithelial permeability. Increased lung volumes were effected by application of 5 or 7 cm H 2 O positive end-expired pressure (5-PEEP and 7-PEEP, respectively). Lung injury was induced either by intravenous oleic acid (OA, 27-73 μl/kg) or inhalation of nitrogen dioxide (NO 2 , 80-100 ppm) for 2 h. Postmortem extravascular lung water volume (EVLW) provided an assessment of the degree of lung injury. Tracer clearance rates in animals receiving 5 or 7 cm H 2 O PEEP were not significantly different from controls (K = 0.15 ± 0.05 and 0.24 ± 0.10 vs 0.12 ± 0.03%/min, respectively, p > .05). Animals exposed to NO 2 had faster tracer clearance rates (K = 0.33 ± 0.21%/min, p 2 -exposed guinea pigs correlated well with injury as assessed by EVLW (r = .93, p 2 O PEEP (K = 0.58 ± 0.41%/min, EVLW = 8.1 ± 0.8 mL/g dry lung tissue, p < .05), but there was no correlation between these parameters in this injury model. It is concluded that imaging of the disappearance of radiolabeled HSA in the guinea pig can be a useful index of lung epithelial permeability, but this technique is limited to certain models of lung injury. 33 refs

Colloids Versus Albumin in Large Volume Paracentesis to Prevent Circulatory Dysfunction: Evidence-based Case Report.

Science.gov (United States)

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.

Is serum albumin an independent predictor of post chemotherapy febrile neutropenia?

International Nuclear Information System (INIS)

Saleem, L.; Zahid, N.A.

2017-01-01

Objective: To evaluate the association between serum albumin and risk of post chemotherapy febrile neutropenia. Study Design: Cross sectional study. Place and Duration of Study: Department of oncology, Liaquat National Hospital, from 1st Jan 2015 to 31st Dec 2016. Material and Method: One hundred and sixty-six biopsy proven cancer patients with Eastern cooperative oncology group (ECOG) performance status <2 and without significant co-morbidities received first cycle of chemotherapy during two years study period. Different chemotherapies with moderate to severe risk of FN were used. Patient's pre-treatment serum albumin was measured and patients followed for occurrence of FN. Association between serum albumin and post chemotherapy FN was analyzed. Results: Data of 166 patients was available for final analysis. Post chemotherapy FN was observed in 19.9% (33/166) patients. Pre-chemotherapy serum albumin level was <3.5 mg/dl in (35/166) 21.1% of patients, out of which (15/35) 42.9% developed FN. Serum albumin (p=0.0005) was highly significantly associated with a risk of FN. On analysis of other factors age, gender, body surface area (BSA) and pre-chemotherapy hemoglobin level were not significantly associated with a risk of FN while body mass index (p=0.0005) was found to be associated with risk of FN. Conclusion: Pre-chemotherapy serum albumin levels were found to be statistically significant predictor of postchemotherapy febrile neutropenia.

Defining clogging potential for permeable concrete.

Science.gov (United States)

Kia, Alalea; Wong, Hong S; Cheeseman, Christopher R

2018-08-15

Permeable concrete is used to reduce urban flooding as it allows water to flow through normally impermeable infrastructure. It is prone to clogging by particulate matter and predicting the long-term performance of permeable concrete is challenging as there is currently no reliable means of characterising clogging potential. This paper reports on the performance of a range of laboratory-prepared and commercial permeable concretes, close packed glass spheres and aggregate particles of varying size, exposed to different clogging methods to understand this phenomena. New methods were developed to study clogging and define clogging potential. The tests involved applying flowing water containing sand and/or clay in cycles, and measuring the change in permeability. Substantial permeability reductions were observed in all samples, particularly when exposed to sand and clay simultaneously. Three methods were used to define clogging potential based on measuring the initial permeability decay, half-life cycle and number of cycles to full clogging. We show for the first time strong linear correlations between these parameters for a wide range of samples, indicating their use for service-life prediction. Copyright © 2018 Elsevier Ltd. All rights reserved.

Different Methods of Predicting Permeability in Shale

DEFF Research Database (Denmark)

Mbia, Ernest Ncha; Fabricius, Ida Lykke; Krogsbøll, Anette

by two to five orders of magnitudes at lower vertical effective stress below 40 MPa as the content of clay minerals increases causing heterogeneity in shale material. Indirect permeability from consolidation can give maximum and minimum values of shale permeability needed in simulating fluid flow......Permeability is often very difficult to measure or predict in shale lithology. In this work we are determining shale permeability from consolidation tests data using Wissa et al., (1971) approach and comparing the results with predicted permeability from Kozeny’s model. Core and cuttings materials...... effective stress to 9 μD at high vertical effective stress of 100 MPa. The indirect permeability calculated from consolidation tests falls in the same magnitude at higher vertical effective stress, above 40 MPa, as that of the Kozeny model for shale samples with high non-clay content ≥ 70% but are higher...

Hepatic bilirubin uptake in the isolated perfused rat liver is not facilitated by albumin binding

International Nuclear Information System (INIS)

Stollman, Y.R.; Gaertner, U.; Theilmann, L.; Ohmi, N.; Wolkoff, A.W.

1983-01-01

Bilirubin uptake by the liver has kinetic characteristics which suggest carrier-mediation. Bilirubin is readily bound to albumin. A liver cell surface receptor for albumin has been postulated. The present study was designed to examine directly whether albumin facilitates the hepatic uptake of bilirubin and whether uptake of bilirubin depends on binding to albumin. Rat liver was perfused with a protein-free fluorocarbon medium, and single-pass uptake of 1, 10, or 200 nmol of [ 3 H]bilirubin was determined after injection as an equimolar complex with 125 I-albumin, with 125 I-ligandin, or free with only a [ 14 C]sucrose reference. Uptake of 10 nmol of [ 3 H]bilirubin was 67.5 +/- 3.7% of the dose when injected with 125 I-albumin, 67.4 +/- 6.5% when injected with 125 I-ligandin, and 74.9 +/- 2.4% when injected with [ 14 C]sucrose (P greater than 0.1). At 200 nmol, uptake fell to 46.4 +/- 3.1% ( 125 I-albumin) and 63.3 +/- 3.4% [( 14 C]sucrose) of injected [ 3 H]bilirubin (P less than 0.01), which suggests saturation of the uptake mechanism. When influx was quantitated by the model of Goresky, similar results were obtained. When [ 3 H]bilirubin was injected simultaneously with equimolar 125 I-albumin and a [ 14 C]sucrose reference, there was no delay in 125 I-albumin transit as compared with that of [ 14 C]sucrose. This suggested that the off-rate of albumin from a putative hepatocyte receptor would have to be very rapid, which is unusual for high affinity receptor-ligand interaction. There was no evidence for facilitation of bilirubin uptake by binding to albumin or for interaction of albumin with a liver cell surface receptor. These results suggest that the hepatic bilirubin uptake mechanism is one of high affinity which can extract bilirubin from circulating carriers such as albumin, ligandin, or fluorocarbon

Spectroscopic analysis of the riboflavin-serum albumins interaction on silver nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Voicescu, Mariana, E-mail: voicescu@icf.ro; Angelescu, Daniel G. [Institute of Physical Chemistry ' Ilie Murgulescu' , Romanian Academy (Romania); Ionescu, Sorana [University of Bucharest, Department of Physical Chemistry (Romania); Teodorescu, Valentin S. [Institute of Atomic Physics, National Institute of Materials Physics (Romania)

2013-04-15

Spectrophotometric behavior of riboflavin (RF) adsorbed on silver nanoparticles as well as its interaction with two serum albumins, BSA and HSA, respectively, has been evidenced. The time evolution of the plasmonic features of the complexes formed by RF/BSA/HSA and Ag(0) nanoparticles having an average diameter of 10.0 {+-} 2.0 nm have been investigated by UV-Vis absorption spectroscopy. Using steady-state and time-resolved fluorescence spectroscopy, the structure, stability, and dynamics of the serum albumins have been studied. The efficiency of energy transfer process between RF and serum albumins on silver nanoparticles has been estimated. A reaction mechanism of RF with silver nanoparticles is also proposed and the results are discussed with relevance to the involvement of the silver nanoparticles to the redox process of RF and to the RF-serum albumins interaction into a silver nanoparticles complex.

Spectroscopic analysis of the riboflavin—serum albumins interaction on silver nanoparticles

Science.gov (United States)

Voicescu, Mariana; Angelescu, Daniel G.; Ionescu, Sorana; Teodorescu, Valentin S.

2013-04-01

Spectrophotometric behavior of riboflavin (RF) adsorbed on silver nanoparticles as well as its interaction with two serum albumins, BSA and HSA, respectively, has been evidenced. The time evolution of the plasmonic features of the complexes formed by RF/BSA/HSA and Ag(0) nanoparticles having an average diameter of 10.0 ± 2.0 nm have been investigated by UV-Vis absorption spectroscopy. Using steady-state and time-resolved fluorescence spectroscopy, the structure, stability, and dynamics of the serum albumins have been studied. The efficiency of energy transfer process between RF and serum albumins on silver nanoparticles has been estimated. A reaction mechanism of RF with silver nanoparticles is also proposed and the results are discussed with relevance to the involvement of the silver nanoparticles to the redox process of RF and to the RF-serum albumins interaction into a silver nanoparticles complex.

Reutilization of amino acid carbons in relation to albumin turnover in nongrowing mice with sarcoma

International Nuclear Information System (INIS)

Karlberg, I.; Ekman, L.; Edstroem, S.; Schersten, T.; Lundholm, K.

1982-01-01

Reutilization of amino acid carbons was evaluated in relation to increased turnover of albumin in tumor-bearing mice. A methylcholanthrene-induced sarcoma (MCG 101) was used in nongrowing mice (C57BL/6J). Sarcoma-bearing mice developed hypoalbuminemia, but pair-fed controls did not. The hypoalbuminemia was caused by increased albumin degradation rate, measured by injection of Na 214 CO 3 , and by exponentially increased deposition of albumin into the tumor compartment. The fractional synthesis rate of albumin was doubled in tumor-bearing mice compared with controls. The translational capacity of albumin synthesis evaluated in vitro was maintained in tumor host livers. The recycling of [ 14 C]leucine carbons was almost extinguished in plasma albumin of sarcoma-bearing mice, while that of control mice contributed to 30 to 40% of the total leucine carbon flux in turned over albumin. The recycling of arginine carbons was also different when measured after simultaneous injection of [guanido- 14 C]arginine and [2,3- 3 H]arginine. The hepatic pool of free leucine was increased by 22% in tumor-bearing mice. It is concluded that increased albumin degradation in cancer may be a disordered event and is earlier and of initially greater quantitative importance than is altered synthesis of albumin for the development of hypoalbuminemia in experimental cancer

Early Identification of the Patient with Endotheliopathy of Trauma by Arrival Serum Albumin

DEFF Research Database (Denmark)

Rodriguez, Erika Gonzalez; Cardenas, Jessica C; Lopez, Ernesto

2017-01-01

OBJECTIVE: Traumatic endotheliopathy (EoT) is associated with glycocalyx breakdown and capillary leak resulting in the extravasation of proteins. We hypothesized that lower serum albumin levels are associated with EoT, poor outcomes, and can be used for early EoT screening in trauma patients. MET...... with leakage of albumin from the intravascular compartment, which reemphasizes that arrival albumin may be a novel and timely approach to the identification of patients needing endothelial rescue therapy.......OBJECTIVE: Traumatic endotheliopathy (EoT) is associated with glycocalyx breakdown and capillary leak resulting in the extravasation of proteins. We hypothesized that lower serum albumin levels are associated with EoT, poor outcomes, and can be used for early EoT screening in trauma patients....... METHODS: We enrolled severely injured trauma patients with serum albumin levels available on admission. Syndecan-1 and soluble thrombomodulin were quantified from plasma by ELISA. Demographic and clinical data were obtained. We evaluated the association of serum albumin and EoT+ (syndecan-1 level ≥40 ng...

Octanoate in Human Albumin Preparations Is Detrimental to Mesenchymal Stromal Cell Culture

Directory of Open Access Journals (Sweden)

Way-Wua Wong

2015-01-01

Full Text Available Cell therapies hold great promise as the next major advance in medical treatment. To enable safe, effective ex vivo culture whilst maintaining cell phenotype, growth media constituents must be carefully controlled. We have used a chemically defined mesenchymal stromal cell culture medium to investigate the influence of different preparations of human serum albumin. We examined two aspects of cell culture, growth rate as measured by population doubling time and colony forming ability which is a representative measure of the stemness of the cell population. Albumin preparations showed comparative differences in both of these criteria. Analysis of the albumin bound fatty acids also showed differences depending on the manufacturing procedure used. We demonstrated that octanoate, an additive used to stabilize albumin during pasteurization, slows growth and lowers colony forming ability during ex vivo culture. Further to this we also found the level of Na+/K+ ATPase, a membrane bound cation pump inhibited by octanoate, is increased in cells exposed to this compound. We conclude that the inclusion of human serum albumin in ex vivo growth media requires careful consideration of not only the source of albumin, but also the associated molecular cargo, for optimal cell growth and behavior.

Reversal of hepatorenal syndrome type 1 with terlipressin plus albumin vs. placebo plus albumin in a pooled analysis of the OT-0401 and REVERSE randomised clinical studies.

Science.gov (United States)

Sanyal, A J; Boyer, T D; Frederick, R T; Wong, F; Rossaro, L; Araya, V; Vargas, H E; Reddy, K R; Pappas, S C; Teuber, P; Escalante, S; Jamil, K

2017-06-01

The goal of hepatorenal syndrome type 1 (HRS-1) treatment is to improve renal function. Terlipressin, a synthetic vasopressin analogue, is a systemic vasoconstrictor used for the treatment of HRS-1, where it is available. To compare the efficacy of terlipressin plus albumin vs. placebo plus albumin in patients with HRS-1. Pooled patient-level data from two large phase 3, randomised, placebo-controlled studies were analysed for HRS reversal [serum creatinine (SCr) value ≤133 μmol/L], 90-day survival, need for renal replacement therapy and predictors of HRS reversal. Patients received intravenous terlipressin 1-2 mg every 6 hours plus albumin or placebo plus albumin up to 14 days. The pooled analysis comprised 308 patients (terlipressin: n = 153; placebo: n = 155). HRS reversal was significantly more frequent with terlipressin vs. placebo (27% vs. 14%; P = 0.004). Terlipressin was associated with a more significant improvement in renal function from baseline until end of treatment, with a mean between-group difference in SCr concentration of -53.0 μmol/L (P albumin resulted in a significantly higher rate of HRS reversal vs. albumin alone in patients with HRS-1. Terlipressin treatment is associated with improved renal function. (ClinicalTrials.gov identifier: OT-0401, NCT00089570; REVERSE, NCT01143246). © 2017 The Authors. Alimentary Pharmacology and Therapeutics published by John Wiley & Sons Ltd.

Development and characterization of glutathione-conjugated albumin nanoparticles for improved brain delivery of hydrophilic fluorescent marker.

Science.gov (United States)

Patel, Prerak J; Acharya, Niyati S; Acharya, Sanjeev R

2013-01-01

The glutathione-conjugated bovine serum albumin (BSA) nanoparticles were constructed in the present exploration as a novel biodegradable carrier for brain-specific drug delivery with evaluation of its in vitro and in vivo delivery properties. BSA nanocarriers were activated and conjugated to the distal amine functions of the glutathione via carbodiimide chemistry using EDAC as a mediator. These nanoparticles were characterized for particle shape, average size, SPAN value, drug entrapment and in vitro drug release. Further, presence of glutathione on the surface of BSA nanoparticles was confirmed by Ellman's assay, which has suggested that approximately 750 units of glutathione were conjugated per BSA nanoparticle. To evaluate the brain delivery properties of the glutathione-conjugated BSA nanoparticles fluorescein sodium was used as a model hydrophilic compound. Permeability and neuronal uptake properties of developed formulations were evaluated against the MDCK-MDR1 endothelial and neuro-glial cells, respectively. The permeability of glutathione-conjugated BSA nanoparticles across the monolayer of MDCK-MDR1 endothelial tight junction was shown significantly higher than that of unconjugated nanoparticles and fluorescein sodium solution. Similarly, glutathione-conjugated nanoparticles exhibited considerably higher uptake by neuro-glial cells which was inferred by high fluorescence intensity under microscope in comparison to unconjugated nanoparticles and fluorescein sodium solution. Following an intravenous administration, nearly three folds higher fluorescein sodium was carried to the rat brain by glutathione-conjugated nanoparticles as compared to unconjugated nanoparticles. The significant in vitro and in vivo results suggest that glutathione-conjugated BSA nanoparticles is a promising brain drug delivery system with low toxicity.

Quantifying porosity, compressibility and permeability in Shale

DEFF Research Database (Denmark)

Mbia, Ernest Ncha; Fabricius, Ida Lykke; Frykman, Peter

strain data. We found that Kozeny's modelled permeability fall in the same order of magnitude with measured permeability for shale rich in kaolinite but overestimates permeability by two to three orders of magnitudes for shale with high content of smectite. The empirical Yang and Aplin model gives good...... permeability estimate comparable to the measured one for shale rich in smectite. This is probably because Yang and Aplin model was calibrated in London clay which is rich in smectite....

Albumin infusion in patients undergoing large-volume paracentesis: a meta-analysis of randomized trials.

Science.gov (United States)

Bernardi, Mauro; Caraceni, Paolo; Navickis, Roberta J; Wilkes, Mahlon M

2012-04-01

Albumin infusion reduces the incidence of postparacentesis circulatory dysfunction among patients with cirrhosis and tense ascites, as compared with no treatment. Treatment alternatives to albumin, such as artificial colloids and vasoconstrictors, have been widely investigated. The aim of this meta-analysis was to determine whether morbidity and mortality differ between patients receiving albumin versus alternative treatments. The meta-analysis included randomized trials evaluating albumin infusion in patients with tense ascites. Primary endpoints were postparacentesis circulatory dysfunction, hyponatremia, and mortality. Eligible trials were sought by multiple methods, including computer searches of bibliographic and abstract databases and the Cochrane Library. Results were quantitatively combined under a fixed-effects model. Seventeen trials with 1,225 total patients were included. There was no evidence of heterogeneity or publication bias. Compared with alternative treatments, albumin reduced the incidence of postparacentesis circulatory dysfunction (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.27-0.55). Significant reductions in that complication by albumin were also shown in subgroup analyses versus each of the other volume expanders tested (e.g., dextran, gelatin, hydroxyethyl starch, and hypertonic saline). The occurrence of hyponatremia was also decreased by albumin, compared with alternative treatments (OR, 0.58; 95% CI, 0.39-0.87). In addition, mortality was lower in patients receiving albumin than alternative treatments (OR, 0.64; 95% CI, 0.41-0.98). This meta-analysis provides evidence that albumin reduces morbidity and mortality among patients with tense ascites undergoing large-volume paracentesis, as compared with alternative treatments investigated thus far. Copyright © 2011 American Association for the Study of Liver Diseases.

188Re-microspheres of albumin - the potential preparation for radiotherapy

International Nuclear Information System (INIS)

Dyomin, D.N.; Petriev, V.M.

2000-01-01

In this paper author describe preparation the albumin microspheres labelled with rhenium-188. We undertake an attempt to develop kits to the generator of rhenium-188 on the basis of albumin microspheres for radiotherapy of both oncological and non-oncological diseases. Microspheres, rhenium-188 with sizes 1 0-20 micron for treatment of rheumatoid arthritis (damage of large and intermediate joints), intraperitoneal administration and intrapleural administration at metastases covering a cavity. Microspheres, Re-188 with sizes 40-60 micron for treatment of disseminated kidney cancer (intraarterial, selectively), intratumoral administration to damaged nodules less than 2-3 cm. Microspheres, Re-188 with sizes 80-100 micron for large neoplasms and metastases of liver (intraarterial, selectively), intratumoral administration to damaged nodules with sizes over 3 cm. Preparation of albumin microspheres is carried out by thermal denaturation of protein in vegetable oil. Microspheres are obtained with the necessary range of sizes by ultrasonic fractionation. At our laboratory the method of preparation of albumin microspheres with any sizes of particles (from 5 -10 up to 800 -1000 microns) has been developed. (authors)

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

Science.gov (United States)

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. Copyright © 2016 Elsevier B.V. All rights reserved.

Microorganism Removal in Permeable Pavement Parking Lots ...

Science.gov (United States)

Three types of permeable pavements (pervious concrete, permeable interlocking concrete pavers, and porous asphalt) were monitored at the Edison Environmental Center in Edison, New Jersey for indicator organisms such as fecal coliform, enterococci, and E. coli. Results showed that porous asphalt had much lower concentration in monitored infiltrate compared to pervious concrete and permeable interlocking concrete pavers. Concentrations of monitored organisms in infiltrate from porous asphalt were consistently below the bathing water quality standard. Fecal coliform and enterococci exceeded bathing water quality standards more than 72% and 34% of the time for permeable interlocking concrete pavers and pervious concrete, respectively. Purpose is to evaluate the performance of permeable pavement in removing indicator organisms from infiltrating stormwater runoff.

Increased albumin permeation in eyes, aorta, and kidney of hypertensive rats fed galactose

International Nuclear Information System (INIS)

Tilton, R.G.; LaRose, L.; Chang, K.; Weigel, C.J.; Williamson, J.R.

1986-01-01

These experiments were undertaken to determine whether ingestion of galactose increases albumin permeation in the vasculature of hypertensive rats. 50% dextrin (control) or 50% galactose diets were fed to unilaterally nephrectomized, male Sprague-Dawley rats weighing 200 g. Hypertension (systolic pressure >175 mmHg) was induced by weekly IM injections of 25 mg/kg DOCA and 1% saline drinking water; 3 months later 125 I-albumin permeation was assessed in whole eyes, aorta and kidneys. 125 I-albumin permeation was significantly increased in all 3 tissues of hypertensive rats (n = 9) vs controls (n = 9): aorta (3.30 +/- 0.19 (SD) vs 2.87 +/- 0.14), eye (3.15 +/- 0.14 vs 2.59 +/- 0.11), and kidney (6.58 +/- 0.63 vs 3.85 +/- 0.50). Albumin permeation was increased still further in hypertensive rats fed the galactose diet (n = 8): aorta (3.75 +/- 0.38), eye (3.82 +/- 0.17), and kidney (10.74 +/- 3.13). Hypertension +/- galactose feeding had no effect on albumin permeation in lung, skin, or brain. These findings indicate that: (1) hypertension increases albumin permeation in vessels affected by diabetic vascular diseases, and 2) hypertension-induced increases in albumin permeation are increased still further by galactose ingestion, presumably mediated by imbalances in polyol/insitol metabolism (analogous to those induced by diabetes) independent of hyperglycemia and/or insulinopenia

Posttranslational nitro-glycative modifications of albumin in Alzheimer's disease: implications in cytotoxicity and amyloid-β peptide aggregation.

Science.gov (United States)

Ramos-Fernández, Eva; Tajes, Marta; Palomer, Ernest; Ill-Raga, Gerard; Bosch-Morató, Mònica; Guivernau, Biuse; Román-Dégano, Irene; Eraso-Pichot, Abel; Alcolea, Daniel; Fortea, Juan; Nuñez, Laura; Paez, Antonio; Alameda, Francesc; Fernández-Busquets, Xavier; Lleó, Alberto; Elosúa, Roberto; Boada, Mercé; Valverde, Miguel A; Muñoz, Francisco J

2014-01-01

Glycation and nitrotyrosination are pathological posttranslational modifications that make proteins prone to losing their physiological properties. Since both modifications are increased in Alzheimer's disease (AD) due to amyloid-β peptide (Aβ) accumulation, we have studied their effect on albumin, the most abundant protein in cerebrospinal fluid and blood. Brain and plasmatic levels of glycated and nitrated albumin were significantly higher in AD patients than in controls. In vitro turbidometry and electron microscopy analyses demonstrated that glycation and nitrotyrosination promote changes in albumin structure and biochemical properties. Glycated albumin was more resistant to proteolysis and less uptake by hepatoma cells occurred. Glycated albumin also reduced the osmolarity expected for a solution containing native albumin. Both glycation and nitrotyrosination turned albumin cytotoxic in a cell type-dependent manner for cerebral and vascular cells. Finally, of particular relevance to AD, these modified albumins were significantly less effective in avoiding Aβ aggregation than native albumin. In summary, nitrotyrosination and especially glycation alter albumin structural and biochemical properties, and these modifications might contribute for the progression of AD.

The relative role of serum albumin and urinary creatinine as ...

African Journals Online (AJOL)

Their weight, Body mass index, serum albumin and 24-hour urinary creatinine were determined before treatment, at the end of the 1st, 2nd, 4th and 6th month of treatment. Using ANOVA, the mean values of the weight, BIM and serum albumin were analysed with further analysis paired student T- test of the pre-treatment ...

Possibilities of Using Combined Optical and AFM Investigations of Albumin

Science.gov (United States)

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

2018-02-01

The results of a complex study of 10% aqueous solution of human serum albumin using methods of optical and atomic force microscopy have been presented. The fine structure of main structures of albumin facies (vitreous matrix and concretions) has been revealed and some observed structural effects have been interpreted from the viewpoint of polymer materials science.

Use of Interface Treatment to Reduce Emissions from Residuals in Lower Permeability Zones to Groundwater flowing Through More Permeable Zones (Invited)

Science.gov (United States)

Johnson, P.; Cavanagh, B.; Clifton, L.; Daniels, E.; Dahlen, P.

2013-12-01

Many soil and groundwater remediation technologies rely on fluid flow for contaminant extraction or reactant delivery (e.g., soil vapor extraction, pump and treat, in situ chemical oxidation, air sparging, enhanced bioremediation). Given that most unconsolidated and consolidated settings have permeability contrasts, the outcome is often preferential treatment of more permeable zones and ineffective treatment of the lower permeability zones. When this happens, post-treatment contaminant emissions from low permeability zone residuals can cause unacceptable long-term impacts to groundwater in the transmissive zones. As complete remediation of the impacted lower permeability zones may not be practicable with conventional technologies, one might explore options that lead to reduction of the contaminant emissions to acceptable levels, rather than full remediation of the lower permeability layers. This could be accomplished either by creating a sustained emission reaction/attenuation zone at the high-low permeability interface, or by creating a clean soil zone extending sufficiently far into the lower permeability layer to cause the necessary reduction in contaminant concentration gradient and diffusive emission. These options are explored in proof-of-concept laboratory-scale physical model experiments. The physical models are prepared with two layers of contrasting permeability and either dissolved matrix storage or nonaqueous phase liquid (NAPL) in the lower permeability layer. A dissolved oxidant is then delivered to the interface via flow across the higher permeability layer and changes in contaminant emissions from the low permeability zone are monitored before, during, and after oxidant delivery. The use of three oxidants (dissolved oxygen, hydrogen peroxide and sodium persulfate) for treatment of emissions from petroleum hydrocarbon residuals is examined.

The effect of Cerasus avium stalk extract on albumin glycation reaction

Directory of Open Access Journals (Sweden)

Mohadeseh Abdoli

2014-10-01

Full Text Available Background: Non-enzymatic glycosylation of proteins is the major cause of diabetic complications. The inhibition of glycation process can reduce complications of diabetes. In the Iranian traditional medicine, the decoction (boiled extraction of Cerasus avium stalk is used as a hypoglycemic agent. The aim of this study was to investigate the in vitro inhibitory effects of decoction and ethanolic and aqueous extracts of Cerasus avium stalk on albumin glycation reaction. Methods: In this experimental study, first, the ethanolic, aqueous and decoction extracts of Cerasus avium stalk were prepared. Then, different concentrations of these extracts were prepared and added to albumin and glucose solutions. Finally, compared to control group that was not treated with any extracts, the albumin glycation rate in the groups treated with various concentrations of extracts was evaluated using TBA (thio-barbituric acid method. Results: The results showed that compared to control group, decoction of Cerasus avium stalk in the concentrations of 20, 10 and 2 mg/dl could reduce albumin glycation to 85.10±1.55, 72.35±1.75 and 51.25±1.22 %, respectively (P>0.001. Moreover, in the concentration of 20 mg/dl, the inhibitory effect of decoction of Cerasus avium stalk on the albumin glycation reaction was higher than those of aqueous (P=0.021 and ethanolic (P=0.009 extracts. Conclusion: The findings showed that the extracs of Cerasus avium stalk, in particular in the decoction form, could significantly reduce the rate of albumin glycation; therefore, it can be used for decreasing diabetes mellitus complications.

Restricted Albumin Utilization Is Safe and Cost Effective in a Cardiac Surgery Intensive Care Unit.

Science.gov (United States)

Rabin, Joseph; Meyenburg, Timothy; Lowery, Ashleigh V; Rouse, Michael; Gammie, James S; Herr, Daniel

2017-07-01

Volume expansion is often necessary after cardiac surgery, and albumin is often administered. Albumin's high cost motivated an attempt to reduce its utilization. This study analyzes the impact limiting albumin infusion in a cardiac surgery intensive care unit. This retrospective study analyzed albumin use between April 2014 and April 2015 in patients admitted to a cardiac surgery intensive care unit. During the first 9 months, there were no restrictions. In January 2015, institutional guidelines limited albumin use to patients requiring more than 3 L crystalloid in the early postoperative period, hypoalbuminemic patients, and to patients considered fluid overloaded. Albumin utilization was obtained from pharmacy records and compared with outcome quality metrics. In all, 1,401 patients were admitted over 13 months. Albumin use, mortality, ventilator days, patients receiving transfusions, and length of stay were compared for 961 patients before and 440 patients after guidelines were initiated. After restrictive guidelines were instituted, albumin utilization was reduced from a mean of 280 monthly doses to a mean of 101 monthly doses (p albumin doses, the cardiac surgery intensive care unit demonstrated more than $45,000 of wholesale savings per month after restrictions were implemented. Albumin restriction in the cardiac surgery intensive care unit was feasible and safe. Significant reductions in utilization and cost with no changes in morbidity or mortality were demonstrated. These findings may provide a strategy for reducing cost while maintaining quality of care. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Controlling DC permeability in cast steels

Energy Technology Data Exchange (ETDEWEB)

Sumner, Aaran, E-mail: aaran.sumner@nottingham.ac.uk [University of Nottingham, Nottingham University Park Campus, Nottingham NG7 2RD, England (United Kingdom); Gerada, Chris, E-mail: chris.gerada@nottingham.ac.uk [Electrical Machines, University of Nottingham, Tower Building, Nottingham NG7 2RD, England (United Kingdom); Brown, Neil, E-mail: neil.brown@cummins.com [Advanced Electrical Machines Research and Technology at Cummins Power Generation, Peterborough PE2 6FZ, England (United Kingdom); Clare, Adam, E-mail: adam.clare@nottingham.ac.uk [Advanced Manufacturing, University of Nottingham, University Park Campus, Nottingham NG7 2RD, England (United Kingdom)

2017-05-01

Annealing (at multiple cooling rates) and quenching (with tempering) was performed on specimens of cast steel of varying composition. The aim was to devise a method for selecting the steel with the highest permeability, from any given range of steels, and then increasing the permeability by heat treatment. Metallographic samples were imaged using optical microscopy to show the effect of the applied heat treatments on the microstructure. Commonly cast steels can have DC permeability altered by the careful selection of a heat treatment. Increases of up to 381% were achieved by annealing using a cooling rate of 6.0 °C/min. Annealing was found to cause the carbon present in the steel to migrate from grain boundaries and from within ferrite crystals into adjacent pearlite crystals. The migration of the carbon resulted in less carbon at grain boundaries and within ferrite crystals reducing the number of pinning sites between magnetic domains. This gives rise to a higher permeability. Quenching then tempering was found to cause the formation of small ferrite crystals with the carbon content of the steel predominately held in the martensitic crystal structures. The results show that with any given range of steel compositions the highest baseline DC permeability will be found with the steel that has the highest iron content and the lowest carbon content. For the samples tested in this paper a cooling rate of 4.5 °C/min resulted in the relative permeability of the sample with the highest baseline permeability, AS4, increasing from 783 to 1479 at 0.5 T. This paper shows how heat treatments commonly applied to hypoeutectoid cast steels, to improve their mechanical performance, can be used to also enhance electromagnetic properties of these alloys. The use of cast steels allows the creation of DC components for electrical machines not possible by the widely used method of stacking of electrical grade sheet steels. - Highlights: • A range of structural steels had their

Controlling DC permeability in cast steels

International Nuclear Information System (INIS)

Sumner, Aaran; Gerada, Chris; Brown, Neil; Clare, Adam

2017-01-01

Annealing (at multiple cooling rates) and quenching (with tempering) was performed on specimens of cast steel of varying composition. The aim was to devise a method for selecting the steel with the highest permeability, from any given range of steels, and then increasing the permeability by heat treatment. Metallographic samples were imaged using optical microscopy to show the effect of the applied heat treatments on the microstructure. Commonly cast steels can have DC permeability altered by the careful selection of a heat treatment. Increases of up to 381% were achieved by annealing using a cooling rate of 6.0 °C/min. Annealing was found to cause the carbon present in the steel to migrate from grain boundaries and from within ferrite crystals into adjacent pearlite crystals. The migration of the carbon resulted in less carbon at grain boundaries and within ferrite crystals reducing the number of pinning sites between magnetic domains. This gives rise to a higher permeability. Quenching then tempering was found to cause the formation of small ferrite crystals with the carbon content of the steel predominately held in the martensitic crystal structures. The results show that with any given range of steel compositions the highest baseline DC permeability will be found with the steel that has the highest iron content and the lowest carbon content. For the samples tested in this paper a cooling rate of 4.5 °C/min resulted in the relative permeability of the sample with the highest baseline permeability, AS4, increasing from 783 to 1479 at 0.5 T. This paper shows how heat treatments commonly applied to hypoeutectoid cast steels, to improve their mechanical performance, can be used to also enhance electromagnetic properties of these alloys. The use of cast steels allows the creation of DC components for electrical machines not possible by the widely used method of stacking of electrical grade sheet steels. - Highlights: • A range of structural steels had their

Preparation of Tc-99m human serum albumin using stannous citrate and stannous chloride

International Nuclear Information System (INIS)

El-Asrag, H.A.; El-Wetery, A.S.; El-Mohty, A.A.

1988-01-01

99mTc-albumin is widely used as radioactive indicator in the measurement of cardiac output by external counting techniques and in blood volume studies. The quality of 99mTc-albumin depends on the method of preparation. A comparative study had been carried out on the 99mTc-albumin preparation by the stannous chloride, stannous tartarate and stannous citrate method. The different parameters investigated for each method include: pH, albumin concentration, reductant concentration and ascorbic acid as antioxidant stabilizer. The biological distribution of 99mTc-albumin, prepared by different methods, were determined in mice and rats. A procedure was developed for the preparation of stannous human serum albumin (HSA) kit for human application the kit provides a freeze dried sterile formulation for reconstitution with sterile 99mTc pertechnetate solution to give 99mTc-Hsa, the effect of irradiation sterilization on the freeze dried kit was studied by spectrophotometric determination and biological distribution in mice and rats

Microarchitecture of the Augmented Bone Following Sinus Elevation with an Albumin Impregnated Demineralized Freeze-Dried Bone Allograft (BoneAlbumin versus Anorganic Bovine Bone Mineral: A Randomized Prospective Clinical, Histomorphometric, and Micro-Computed Tomography Study

Directory of Open Access Journals (Sweden)

Kivovics Márton

2018-01-01

Full Text Available Serum albumin has been identified as an endogenous protein that is integral to early bone regeneration. We hypothesized that albumin addition to allografts may result in better bone remodeling than what can be achieved with anorganic xenografts. Sinus elevations were performed at 32 sites of 18 patients with the lateral window technique. Sites either received filling with an anorganic bovine bone mineral (ABBM, BioOss, Geistlich, CH or albumin impregnated allograft (BoneAlbumin, OrthoSera, AT. After 6-months patients received dental implants and 16 bone core biopsy samples were obtained from the ABBM filled, and 16 from the BoneAlbumin augmented sites. The biopsies were examined by histomorphometry and µCT. Percentage of the residual graft in the BoneAlbumin group was 0–12.7%, median 5.4% vs. ABBM 6.3–35.9%, median 16.9%, p < 0.05. Results of the µCT analysis showed that the microarchitecture of the augmented bone in the BoneAlbumin group resembles that of the native maxilla in morphometric parameters Trabecular Pattern Factor and Connectivity. Our data show that while ABBM successfully integrates into the newly formed bone tissue as persisting particles, BoneAlbumin is underway towards complete remodeling with new bone closely resembling that of the intact maxilla.

Determination of Urine Albumin by New Simple High-Performance Liquid Chromatography Method.

Science.gov (United States)

Klapkova, Eva; Fortova, Magdalena; Prusa, Richard; Moravcova, Libuse; Kotaska, Karel

2016-11-01

A simple high-performance liquid chromatography (HPLC) method was developed for the determination of albumin in patients' urine samples without coeluting proteins and was compared with the immunoturbidimetric determination of albumin. Urine albumin is important biomarker in diabetic patients, but part of it is immuno-nonreactive. Albumin was determined by high-performance liquid chromatography (HPLC), UV detection at 280 nm, Zorbax 300SB-C3 column. Immunoturbidimetric analysis was performed using commercial kit on automatic biochemistry analyzer COBAS INTEGRA ® 400, Roche Diagnostics GmbH, Manheim, Germany. The HLPC method was fully validated. No significant interference with other proteins (transferrin, α-1-acid glycoprotein, α-1-antichymotrypsin, antitrypsin, hemopexin) was found. The results from 301 urine samples were compared with immunochemical determination. We found a statistically significant difference between these methods (P = 0.0001, Mann-Whitney test). New simple HPLC method was developed for the determination of urine albumin without coeluting proteins. Our data indicate that the HPLC method is highly specific and more sensitive than immunoturbidimetry. © 2016 Wiley Periodicals, Inc.

Measurement of urinary albumin excretion rate (AER) in normal and diabetic subjects

International Nuclear Information System (INIS)

Giampetro, O.; Clerico, A.; Cruschelli, L.; Miccoli, R.; Dipalma, L.; Navalesi, R.

1987-01-01

The chemico-clinical characteristics of two commercial RIA kits for the measurement of urinary albumin excretion in normal and diabetic subjects were compared. The chief difference between the two methods concerns the bound/free separation of the antigen, since one employs the second antybody plus PEG (Sclavo Kit), while the other uses the solid phase [antiserum bound to sepharose (Pharmacia kit)]. The two RIA methods have demonstrated a similar degree of sensitivity, feasibility and cost. The precision of the two RIAs was also similar, although the Sclavo kit has shown a better precision for lower albumin concentrations and the Pharmacia kit for higher values. In diabetic patients, elevated urinary albumin concentrations (>60 mg/L) have been found more frequently than low values (<5 mg/L); hence the Pharmacia kit seems to be preferable, because it less frequently needs dilution of urinary sample for measuring with a better precision supranormal urinary albumin values. A significant bias (about 15%) was found between the two RIAs. Bias between different albumin RIA methods could partially explain the differences of normal values previously reported in the literature

Albumin-associated lipids regulate human embryonic stem cell self-renewal.

Directory of Open Access Journals (Sweden)

Francesc R Garcia-Gonzalo

Full Text Available BACKGROUND: Although human embryonic stem cells (hESCs hold great promise as a source of differentiated cells to treat several human diseases, many obstacles still need to be surmounted before this can become a reality. First among these, a robust chemically-defined system to expand hESCs in culture is still unavailable despite recent advances in the understanding of factors controlling hESC self-renewal. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we attempted to find new molecules that stimulate long term hESC self-renewal. In order to do this, we started from the observation that a commercially available serum replacement product has a strong positive effect on the expansion of undifferentiated hESCs when added to a previously reported chemically-defined medium. Subsequent experiments demonstrated that the active ingredient within the serum replacement is lipid-rich albumin. Furthermore, we show that this activity is trypsin-resistant, strongly suggesting that lipids and not albumin are responsible for the effect. Consistent with this, lipid-poor albumin shows no detectable activity. Finally, we identified the major lipids bound to the lipid-rich albumin and tested several lipid candidates for the effect. CONCLUSIONS/SIGNIFICANCE: Our discovery of the role played by albumin-associated lipids in stimulating hESC self-renewal constitutes a significant advance in the knowledge of how hESC pluripotency is maintained by extracellular factors and has important applications in the development of increasingly chemically defined hESC culture systems.

Raman spectroscopy provides a powerful diagnostic tool for accurate determination of albumin glycation.

Science.gov (United States)

Dingari, Narahara Chari; Horowitz, Gary L; Kang, Jeon Woong; Dasari, Ramachandra R; Barman, Ishan

2012-01-01

We present the first demonstration of glycated albumin detection and quantification using Raman spectroscopy without the addition of reagents. Glycated albumin is an important marker for monitoring the long-term glycemic history of diabetics, especially as its concentrations, in contrast to glycated hemoglobin levels, are unaffected by changes in erythrocyte life times. Clinically, glycated albumin concentrations show a strong correlation with the development of serious diabetes complications including nephropathy and retinopathy. In this article, we propose and evaluate the efficacy of Raman spectroscopy for determination of this important analyte. By utilizing the pre-concentration obtained through drop-coating deposition, we show that glycation of albumin leads to subtle, but consistent, changes in vibrational features, which with the help of multivariate classification techniques can be used to discriminate glycated albumin from the unglycated variant with 100% accuracy. Moreover, we demonstrate that the calibration model developed on the glycated albumin spectral dataset shows high predictive power, even at substantially lower concentrations than those typically encountered in clinical practice. In fact, the limit of detection for glycated albumin measurements is calculated to be approximately four times lower than its minimum physiological concentration. Importantly, in relation to the existing detection methods for glycated albumin, the proposed method is also completely reagent-free, requires barely any sample preparation and has the potential for simultaneous determination of glycated hemoglobin levels as well. Given these key advantages, we believe that the proposed approach can provide a uniquely powerful tool for quantification of glycation status of proteins in biopharmaceutical development as well as for glycemic marker determination in routine clinical diagnostics in the future.

Raman Spectroscopy Provides a Powerful Diagnostic Tool for Accurate Determination of Albumin Glycation

Science.gov (United States)

Dingari, Narahara Chari; Horowitz, Gary L.; Kang, Jeon Woong; Dasari, Ramachandra R.; Barman, Ishan

2012-01-01

We present the first demonstration of glycated albumin detection and quantification using Raman spectroscopy without the addition of reagents. Glycated albumin is an important marker for monitoring the long-term glycemic history of diabetics, especially as its concentrations, in contrast to glycated hemoglobin levels, are unaffected by changes in erythrocyte life times. Clinically, glycated albumin concentrations show a strong correlation with the development of serious diabetes complications including nephropathy and retinopathy. In this article, we propose and evaluate the efficacy of Raman spectroscopy for determination of this important analyte. By utilizing the pre-concentration obtained through drop-coating deposition, we show that glycation of albumin leads to subtle, but consistent, changes in vibrational features, which with the help of multivariate classification techniques can be used to discriminate glycated albumin from the unglycated variant with 100% accuracy. Moreover, we demonstrate that the calibration model developed on the glycated albumin spectral dataset shows high predictive power, even at substantially lower concentrations than those typically encountered in clinical practice. In fact, the limit of detection for glycated albumin measurements is calculated to be approximately four times lower than its minimum physiological concentration. Importantly, in relation to the existing detection methods for glycated albumin, the proposed method is also completely reagent-free, requires barely any sample preparation and has the potential for simultaneous determination of glycated hemoglobin levels as well. Given these key advantages, we believe that the proposed approach can provide a uniquely powerful tool for quantification of glycation status of proteins in biopharmaceutical development as well as for glycemic marker determination in routine clinical diagnostics in the future. PMID:22393405

Recombinant human serum albumin hydrogel as a novel drug delivery vehicle

International Nuclear Information System (INIS)

Hirose, Masaaki; Tachibana, Akira; Tanabe, Toshizumi

2010-01-01

Serum albumin acts as a physiological carrier for various compounds including drugs. A hydrogel consisting of recombinant human serum albumin (rHSA) was prepared to take advantage of drug binding ability of albumin for a sustained drug release carrier. The hydrogel was prepared by mixing rHSA and dithiothreitol and casted to a polystyrene mold. Hydrogel formation was thought to occur through the intermolecular interaction of the hydrophobic groups by protein denaturation. The release of sodium benzoate and salicylic acid from the hydrogel completed in 2 h, while warfarin release continued for 24 h. The total amounts of the drugs released from 100 mg of 15 and 5% rHSA hydrogel were 2.3 and 1.4 μmol for warfarin, 1.4 and 1.1 μmol for salicylic acid and 0.9 and 0.9 μmol for sodium benzoate. These results reflected the order of the binding ability of drugs for intact albumin indicating that the drug binding ability of HSA still remained after the hydrogel formation. However, fibroblast cells attached and proliferated well on the hydrogel, indicating that denaturation of rHSA proceeded to the extent to allow the cell attachment. The present rHSA hydrogel might be suitable for a sustained release carrier of drugs having affinity for albumin.

Recombinant human serum albumin hydrogel as a novel drug delivery vehicle

Energy Technology Data Exchange (ETDEWEB)

Hirose, Masaaki, E-mail: Hirose.Masaaki@mh.mt-pharma.co.jp [Advanced Medical Research Laboratory, Research Division, Mitsubishi Tanabe Pharma Corporation, 3-16-89 Kashima, Yodogawa-ku, Osaka 532-8505 (Japan); Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Tachibana, Akira; Tanabe, Toshizumi [Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan)

2010-06-15

Serum albumin acts as a physiological carrier for various compounds including drugs. A hydrogel consisting of recombinant human serum albumin (rHSA) was prepared to take advantage of drug binding ability of albumin for a sustained drug release carrier. The hydrogel was prepared by mixing rHSA and dithiothreitol and casted to a polystyrene mold. Hydrogel formation was thought to occur through the intermolecular interaction of the hydrophobic groups by protein denaturation. The release of sodium benzoate and salicylic acid from the hydrogel completed in 2 h, while warfarin release continued for 24 h. The total amounts of the drugs released from 100 mg of 15 and 5% rHSA hydrogel were 2.3 and 1.4 {mu}mol for warfarin, 1.4 and 1.1 {mu}mol for salicylic acid and 0.9 and 0.9 {mu}mol for sodium benzoate. These results reflected the order of the binding ability of drugs for intact albumin indicating that the drug binding ability of HSA still remained after the hydrogel formation. However, fibroblast cells attached and proliferated well on the hydrogel, indicating that denaturation of rHSA proceeded to the extent to allow the cell attachment. The present rHSA hydrogel might be suitable for a sustained release carrier of drugs having affinity for albumin.

Isolation, cloning, and characterization of the 2S albumin: A new allergen from hazelnut

NARCIS (Netherlands)

Garino, Cristiano; Zuidmeer, Laurian; Marsh, Justin; Lovegrove, Alison; Morati, Maria; Versteeg, Serge; Schilte, Piet; Shewry, Peter; Arlorio, Marco; van Ree, Ronald

2010-01-01

Scope: 2S albumins are the major allergens involved in severe food allergy to nuts, seeds, and legumes. We aimed to isolate, clone, and express 2S albumin from hazelnut and determine its allergenicity. Methods: 2S albumin from hazelnut extract was purified using size exclusion chromatography and

Frictional stability-permeability relationships for fractures in shales

Science.gov (United States)

Fang, Yi; Elsworth, Derek; Wang, Chaoyi; Ishibashi, Takuya; Fitts, Jeffrey P.

2017-03-01

There is wide concern that fluid injection in the subsurface, such as for the stimulation of shale reservoirs or for geological CO2 sequestration (GCS), has the potential to induce seismicity that may change reservoir permeability due to fault slip. However, the impact of induced seismicity on fracture permeability evolution remains unclear due to the spectrum of modes of fault reactivation (e.g., stable versus unstable). As seismicity is controlled by the frictional response of fractures, we explore friction-stability-permeability relationships through the concurrent measurement of frictional and hydraulic properties of artificial fractures in Green River shale (GRS) and Opalinus shale (OPS). We observe that carbonate-rich GRS shows higher frictional strength but weak neutral frictional stability. The GRS fracture permeability declines during shearing while an increased sliding velocity reduces the rate of permeability decline. By comparison, the phyllosilicate-rich OPS has lower friction and strong stability while the fracture permeability is reduced due to the swelling behavior that dominates over the shearing induced permeability reduction. Hence, we conclude that the friction-stability-permeability relationship of a fracture is largely controlled by mineral composition and that shale mineral compositions with strong frictional stability may be particularly subject to permanent permeability reduction during fluid infiltration.

Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

Science.gov (United States)

Alves, Vinicius M.; Muratov, Eugene; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

2015-01-01

Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R2=0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q2ext = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. PMID:25560673

Raman Spectroscopy Provides a Powerful Diagnostic Tool for Accurate Determination of Albumin Glycation

OpenAIRE

Dingari, Narahara Chari; Kang, Jeon Woong; Dasari, Ramachandra R.; Barman, Ishan; Horowitz, Gary Leigh

2012-01-01

We present the first demonstration of glycated albumin detection and quantification using Raman spectroscopy without the addition of reagents. Glycated albumin is an important marker for monitoring the long-term glycemic history of diabetics, especially as its concentrations, in contrast to glycated hemoglobin levels, are unaffected by changes in erythrocyte life times. Clinically, glycated albumin concentrations show a strong correlation with the development of serious diabetes complications...

SPECTROPHOTOMETRIC ANALYSIS OF BOVINE SERUM ALBUMIN IN PRESENCE OF SOME BISCHALCONES

OpenAIRE

Shweta Garg; Mamta Singh; N. Raghav

2013-01-01

We have synthesized a series of bischalcones by the Claisen-Schmidt condensation and their effect was observed on bovine serum albumin. We have found that the synthesized bischalcones interacted with bovine serum albumin irrespective of the nature and position of the substituent with a little difference.

Transverse Chemotactic Migration of Bacteria from High to Low Permeability Regions in a Dual Permeability Porous Microfluidic Device

Science.gov (United States)

Singh, R.; Olson, M. S.

2011-12-01

Low permeability regions sandwiched between high permeability regions such as clay lenses are difficult to treat using conventional treatment methods. Trace concentrations of contaminants such as non-aqueous phase liquids (NAPLs) remain trapped in these regions and over the time diffuse out into surrounding water thereby acting as a long term source of groundwater contamination. Bacterial chemotaxis (directed migration toward a contaminant source), may be helpful in enhancing bioremediation of such contaminated sites. This study is focused on simulating a two-dimensional dual-permeability groundwater contamination scenario using microfluidic devices and evaluating transverse chemotactic migration of bacteria from high to low permeability regions. A novel bi-layer polydimethylsiloxane (PDMS) microfluidic device was fabricated using photolithography and soft lithography techniques to simulate contamination of a dual- permeability region due to leakage from an underground storage tank into a low permeability region. This device consists of a porous channel through which a bacterial suspension (Escherchia Coli HCB33) is flown and another channel for injecting contaminant/chemo-attractant (DL-aspertic acid) into the porous channel. The pore arrangement in the porous channel contains a 2-D low permeability region surrounded by high permeability regions on both sides. Experiments were performed under chemotactic and non-chemotactic (replacing attractant with buffer solution in the non porous channel) conditions. Images were captured in transverse pore throats at cross-sections 4.9, 9.8, and 19.6 mm downstream from the attractant injection point and bacteria were enumerated in the middle of each pore throat. Bacterial chemotaxis was quantified in terms of the change in relative bacterial counts in each pore throat at cross-sections 9.8 and 19.6 mm with respect to counts at the cross-section at 4.9 mm. Under non-chemotactic conditions, relative bacterial count was observed

Inhibition of the Metabolic Degradation of Filtered Albumin Is a Major Determinant of Albuminuria

Science.gov (United States)

Vuchkova, Julijana; Comper, Wayne D.

2015-01-01

Inhibition of the degradation of filtered albumin has been proposed as a widespread, benign form of albuminuria. There have however been recent reports that radiolabeled albumin fragments in urine are not exclusively generated by the kidney and that in albuminuric states albumin fragment excretion is not inhibited. In order to resolve this controversy we have examined the fate of various radiolabeled low molecular weight protein degradation products (LMWDPs) introduced into the circulation in rats. The influence of puromycin aminonucleoside nephrosis on the processing and excretion of LMWDPs is also examined. The status and destinies of radiolabeled LMWDPs in the circulation are complex. A major finding is that LMWDPs are rapidly eliminated from the circulation (>97% in 2 h) but only small quantities (24 h) due to binding to high molecular weight components in the circulation. If LMWDPs of albumin seen in the urine are produced by extra renal degradation it would require the degradation to far exceed the known catabolic rate of albumin. Alternatively, if an estimate of the role of extra renal degradation is made from the limit of detection of LMWDPs in plasma, then extra renal degradation would only contribute albumin. We confirm that the degradation process for albumin is specifically associated with filtered albumin and this is inhibited in albuminuric states. This inhibition is also the primary determinant of the massive change in intact albuminuria in nephrotic states. PMID:26010895

Buoyancy-activated cell sorting using targeted biotinylated albumin microbubbles.

Directory of Open Access Journals (Sweden)

Yu-Ren Liou

Full Text Available 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

A DSC study of zinc binding to bovine serum albumin (BSA

Directory of Open Access Journals (Sweden)

SANJA OSTOJIC

2007-04-01

Full Text Available The thermal denaturation of bovine serum albumin (BSA is a kinetically and thermodynamically controlled process. The effects of zinc binding to bovine serum albumin (BSA, followed by differential scanning calorimetry (DSC, were investigated in this work, with the purpose of obtaining a better understanding of the albumin/zinc interaction. From the DSC curves, the thermodynamic parameters of protein denaturation were obtained, i.e., the temperature of thermal transition maximum (Tm, calorimetric enthalpy (DHcal, van't Hoff enthalpy (DHvH, the number of binding sites (I, II, the binding constants for each binding site (KbI, KbII and the average number of ligands bound per mole of native protein XN. The thermodynamic data of protein unfolding showed that zinc binding to bovine serum albumin increases the stability of the protein (higher values of DHcal and the different ratio DHcal/DHvH indicates the perturbation of the protein during thermal denaturation.

Age and sex variation in serum albumin concentration: an observational study.

Science.gov (United States)

Weaving, Gary; Batstone, Gifford F; Jones, Richard G

2016-01-01

In the UK, a common reference interval for serum albumin is widely used irrespective of age or sex. Implicit in this is that laboratories produce analytically similar results. This paper challenges the validity of this approach. A three-week collection of results sent to all primary care centres in England has been analysed by age, sex and laboratory. In all, 1,079,193 serum albumin reports were included in this analysis. The mean population serum albumin concentration increases to peak at around age 20 years and then decreases with increasing age. Values in females decrease more rapidly but become close to male values at 60 years. The variation between laboratories was large and potentially clinically significant. Reference intervals for serum albumin should be stratified by age and sex. Until there is greater methodological standardization, laboratories should determine their own reference intervals and not accept a single consensus reference interval. © The Author(s) 2015.

Effect of Exogenous Albumin on the Incidence of Postoperative Acute Kidney Injury in Patients Undergoing Off-pump Coronary Artery Bypass Surgery with a Preoperative Albumin Level of Less Than 4.0 g/dl.

Science.gov (United States)

Lee, Eun-Ho; Kim, Wook-Jong; Kim, Ji-Yeon; Chin, Ji-Hyun; Choi, Dae-Kee; Sim, Ji-Yeon; Choo, Suk-Jung; Chung, Cheol-Hyun; Lee, Jae-Won; Choi, In-Cheol

2016-05-01

Hypoalbuminemia may increase the risk of acute kidney injury (AKI). The authors investigated whether the immediate preoperative administration of 20% albumin solution affects the incidence of AKI after off-pump coronary artery bypass surgery. In this prospective, single-center, randomized, parallel-arm double-blind trial, 220 patients with preoperative serum albumin levels less than 4.0 g/dl were administered 100, 200, or 300 ml of 20% human albumin according to the preoperative serum albumin level (3.5 to 3.9, 3.0 to 3.4, or less than 3.0 g/dl, respectively) or with an equal volume of saline before surgery. The primary outcome measure was AKI incidence after surgery. Postoperative AKI was defined by maximal AKI Network criteria based on creatinine changes. Patient characteristics and perioperative data except urine output during surgery were similar between the two groups studied, the albumin group and the control group. Urine output (median [interquartile range]) during surgery was higher in the albumin group (550 ml [315 to 980]) than in the control group (370 ml [230 to 670]; P = 0.006). The incidence of postoperative AKI in the albumin group was lower than that in the control group (14 [13.7%] vs. 26 [25.7%]; P = 0.048). There were no significant between-group differences in severe AKI, including renal replacement therapy, 30-day mortality, and other clinical outcomes. There were no significant adverse events. Administration of 20% exogenous albumin immediately before surgery increases urine output during surgery and reduces the risk of AKI after off-pump coronary artery bypass surgery in patients with a preoperative serum albumin level of less than 4.0 g/dl.

Modelling of water permeability in cementitious materials

DEFF Research Database (Denmark)

Guang, Ye; Lura, Pietro; van Breugel, K.

2006-01-01

This paper presents a network model to predict the permeability of cement paste from a numerical simulation of its microstructure. Based on a linked list pore network structure, the effective hydraulic conductivity is estimated and the fluid flow is calculated according to the Hagen-Poiseuille law....... The pressure gradient at all nodes is calculated with the Gauss elimination method and the absolute permeability of the pore network is calculated directly from Darcy's law. Finally, the permeability model is validated by comparison with direct water permeability measurements. According to this model...

Bentonite Permeability at Elevated Temperature

Directory of Open Access Journals (Sweden)

Katherine A. Daniels

2017-01-01

Full Text Available Repository designs frequently favour geological disposal of radioactive waste with a backfill material occupying void space around the waste. The backfill material must tolerate the high temperatures produced by decaying radioactive waste to prevent its failure or degradation, leading to increased hydraulic conductivity and reduced sealing performance. The results of four experiments investigating the effect of temperature on the permeability of a bentonite backfill are presented. Bentonite is a clay commonly proposed as the backfill in repository designs because of its high swelling capacity and very low permeability. The experiments were conducted in two sets of purpose-built, temperature controlled apparatus, designed to simulate isotropic pressure and constant volume conditions within the testing range of 4–6 MPa average effective stress. The response of bentonite during thermal loading at temperatures up to 200 °C was investigated, extending the previously considered temperature range. The results provide details of bentonite’s intrinsic permeability, total stress, swelling pressure and porewater pressure during thermal cycles. We find that bentonite’s hydraulic properties are sensitive to thermal loading and the type of imposed boundary condition. However, the permeability change is not large and can mostly be accounted for by water viscosity changes. Thus, under 150 °C, temperature has a minimal impact on bentonite’s hydraulic permeability.

Human albumin prevents 6-hydroxydopamine-induced loss of tyrosine hydroxylase in in vitro and in vivo.

Directory of Open Access Journals (Sweden)

Li-Juan Zhang

Full Text Available Human albumin has recently been demonstrated to protect brain neurons from injury in rat ischemic brain. However, there is no information available about whether human albumin can prevent loss of tyrosine hydroxylase (TH expression of dopaminergic (DA neurons induced by 6-hydroxydopamine (6-OHDA toxicity that is most commonly used to create a rat model of Parkinson's disease (PD. In the present study, two microliters of 1.25% human albumin were stereotaxically injected into the right striatum of rats one day before or 7 days after the 6-OHDA lesion in the same side. D-Amphetamine-induced rotational asymmetry was measured 7 days, 3 and 10 weeks after 6-OHDA lesion. We observed that intrastriatal administration of human albumin significantly reduced the degree of rotational asymmetry. The number of TH-immunoreactive neurons present in the substantia nigra was greater in 6-OHDA lesioned rats following human albumin-treatment than non-human albumin treatment. TH-immunoreactivity in the 6-OHDA-lesioned striatum was also significantly increased in the human albumin-treated rats. To examine the mechanisms underlying the effects of human albumin, we challenged PC12 cells with 6-OHDA as an in vitro model of PD. Incubation with human albumin prevented 6-OHDA-induced reduction of cell viability in PC12 cell cultures, as measured by MTT assay. Furthermore, human albumin reduced 6-OHDA-induced formation of reactive oxygen species (ROS and apoptosis in cultured PC12 cells, as assessed by flow cytometry. Western blot analysis showed that human albumin inhibited 6-OHDA-induced activation of JNK, c-Jun, ERK, and p38 mitogen-activated protein kinases (MAPK signaling in PC12 cultures challenged with 6-OHDA. Human albumin may protect against 6-OHDA toxicity by influencing MAPK pathway followed by anti-ROS formation and anti-apoptosis.

Human Albumin Prevents 6-Hydroxydopamine-Induced Loss of Tyrosine Hydroxylase in In Vitro and In Vivo

Science.gov (United States)

Zhang, Li-Juan; Xue, Yue-Qiang; Yang, Chun; Yang, Wei-Hua; Chen, Long; Zhang, Qian-Jin; Qu, Ting-Yu; Huang, Shile; Zhao, Li-Ru; Wang, Xiao-Min; Duan, Wei-Ming

2012-01-01

Human albumin has recently been demonstrated to protect brain neurons from injury in rat ischemic brain. However, there is no information available about whether human albumin can prevent loss of tyrosine hydroxylase (TH) expression of dopaminergic (DA) neurons induced by 6-hydroxydopamine (6-OHDA) toxicity that is most commonly used to create a rat model of Parkinson's disease (PD). In the present study, two microliters of 1.25% human albumin were stereotaxically injected into the right striatum of rats one day before or 7 days after the 6-OHDA lesion in the same side. D-Amphetamine-induced rotational asymmetry was measured 7 days, 3 and 10 weeks after 6-OHDA lesion. We observed that intrastriatal administration of human albumin significantly reduced the degree of rotational asymmetry. The number of TH-immunoreactive neurons present in the substantia nigra was greater in 6-OHDA lesioned rats following human albumin-treatment than non-human albumin treatment. TH-immunoreactivity in the 6-OHDA-lesioned striatum was also significantly increased in the human albumin-treated rats. To examine the mechanisms underlying the effects of human albumin, we challenged PC12 cells with 6-OHDA as an in vitro model of PD. Incubation with human albumin prevented 6-OHDA-induced reduction of cell viability in PC12 cell cultures, as measured by MTT assay. Furthermore, human albumin reduced 6-OHDA-induced formation of reactive oxygen species (ROS) and apoptosis in cultured PC12 cells, as assessed by flow cytometry. Western blot analysis showed that human albumin inhibited 6-OHDA-induced activation of JNK, c-Jun, ERK, and p38 mitogen-activated protein kinases (MAPK) signaling in PC12 cultures challenged with 6-OHDA. Human albumin may protect against 6-OHDA toxicity by influencing MAPK pathway followed by anti-ROS formation and anti-apoptosis. PMID:22815976

Measurement of the modification and interference rate of urinary albumin detected by size-exclusion HPLC

International Nuclear Information System (INIS)

Markó, Lajos; Molnár, Gergő Attila; Wagner, Zoltán; Szijártó, István; Mérei, Ákos; Wittmann, István; Böddi, Katalin; Szabó, Zoltán; Matus, Zoltán; Kőszegi, Tamás; Nagy, Géza

2009-01-01

The measurement of the excretion of urinary albumin (albuminuria) is an important and well-established method to assess clinical outcomes. A high-performance liquid chromatography (HPLC) method has been introduced to measure albuminuria. Using this method, it was found that commonly used immunological methods do not measure a fraction of urinary albumin. Some authors presumed that the reason of immuno-unreactivity is the modification of urinary albumin; some others presumed that the difference is merely because of interference. In order to decide this question, we established an HPLC method equipped with tandem UV and fluorescent detection to assess the changes in the detectability of albumin with the rate of modification. For this measurement, differently modified forms of albumin were used. Urine samples of diabetic patients were also measured to find a potential connection between the modification rate and clinical parameters. Secondly, we have established a reversed phase HPLC method to assess the interference rate. We conclude that albumin modification does not affect immunoreactivity. The modification rate of urinary albumin in diabetic patients showed a correlation with renal function. The interference rate of the albumin peak was found to be 12.7% on average, which does not explain the difference between the two methods

MRI monitoring of tumor response following angiogenesis inhibition in an experimental human breast cancer model

International Nuclear Information System (INIS)

Turetschek, Karl; Preda, Anda; Shames, David M.; Novikov, Viktor; Roberts, Timothy P.L.; Fu, Yanjun; Brasch, Robert C.; Floyd, Eugenia; Carter, Wayne O.; Wood, Jeanette M.

2003-01-01

The aim of this study was to evaluate the potential of dynamic magnetic resonance imaging (MRI) enhanced by macromolecular contrast agents to monitor noninvasively the therapeutic effect of an anti-angiogenesis VEGF receptor kinase inhibitor in an experimental cancer model. MDA-MB-435, a poorly differentiated human breast cancer cell line, was implanted into the mammary fat pad in 20 female homozygous athymic rats. Animals were assigned randomly to a control (n=10) or drug treatment group (n=10). Baseline dynamic MRI was performed on sequential days using albumin-(GdDTPA) 30 (6.0 nm diameter) and ultrasmall superparamagnetic iron oxide (USPIO) particles (30 nm diameter). Subjects were treated either with PTK787/ZK 222584, a VEGF receptor tyrosine kinase inhibitor, or saline given orally twice daily for 1 week followed by repeat MRI examinations serially using each contrast agent. Employing a unidirectional kinetic model comprising the plasma and interstitial water compartments, tumor microvessel characteristics including fractional plasma volume and transendothelial permeability (K PS ) were estimated for each contrast medium. Tumor growth and the microvascular density, a histologic surrogate of angiogenesis, were also measured. Control tumors significantly increased (P PS ) based on MRI assays using both macromolecular contrast media. In contrast, tumor growth was significantly reduced (P PS values declined slightly. Estimated values for the fractional plasma volume did not differ significantly between treatment groups or contrast agents. Microvascular density counts correlated fairly with the tumor growth rate (r=0.64) and were statistically significant higher (P PS ), using either of two macromolecular contrast media, were able to detect effects of treatment with a VEGF receptor tyrosine kinase inhibitor on tumor vascular permeability. In a clinical setting such quantitative MRI measurements could be used to monitor tumor anti-angiogenesis therapy. (orig.)

Mapping of cat albumin using monoclonal antibodies: identification of determinants common to cat and dog.

Science.gov (United States)

Boutin, Y; Hébert, J; Vrancken, E R; Mourad, W

1989-01-01

Cat and dog albumins from commercial extracts were used to produce monoclonal antibodies (MoAb). Anti-cat albumin MoAb recognized both cat and dog albumin equally, as did anti-dog albumin MoAb; this confirms cross-reactivity between cat and dog. The MoAb were separated into two groups according to their epitopic specificity; they recognized two overlapping epitopes of cat albumin. Furthermore, by competitive inhibition of radio-allergosorbent test (RAST), it was shown that one MoAb group inhibited significantly the binding of human IgE antibodies (from a pool of 13 patients allergic to both cats and dogs) to insolubilized cat or dog extracts. These observations suggest that murine anti-cat or anti-dog MoAb and human IgE antibodies recognize identical or closely related determinants on cat and dog albumin. Images Fig. 1 Fig. 2 PMID:2478325

Cellular Specificity of the Blood-CSF Barrier for Albumin Transfer across the Choroid Plexus Epithelium

DEFF Research Database (Denmark)

Liddelow, Shane A; Dzięgielewska, Katarzyna M; Møllgård, Kjeld

2014-01-01

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...

Comparison of Enzymatic and Ultrasonic Extraction of Albumin from Defatted Pumpkin (Cucurbita pepo Seed Powder

Directory of Open Access Journals (Sweden)

Gia Loi Tu

2015-01-01

Full Text Available In this study, ultrasound- and enzyme-assisted extractions of albumin (water-soluble protein group from defatted pumpkin (Cucurbita pepo seed powder were compared. Both advanced extraction techniques strongly increased the albumin yield in comparison with conventional extraction. The extraction rate was two times faster in the ultrasonic extraction than in the enzymatic extraction. However, the maximum albumin yield was 16 % higher when using enzymatic extraction. Functional properties of the pumpkin seed albumin concentrates obtained using the enzymatic, ultrasonic and conventional methods were then evaluated. Use of hydrolase for degradation of cell wall of the plant material did not change the functional properties of the albumin concentrate in comparison with the conventional extraction. The ultrasonic extraction enhanced water-holding, oil-holding and emulsifying capacities of the pumpkin seed albumin concentrate, but slightly reduced the foaming capacity, and emulsion and foam stability.

Molecular Imaging Approaches to the Evaluation of Infectious Diseases- A Prospective Assessment

Science.gov (United States)

2016-05-25

perspective. The focus of the paper will be on the alphavirus, Venezuelan equine encephalitis virus, and the filovirus, Ebola virus, and on what molecular...damage is often associated with altered permeability and in the brain an altered blood brain barrier. With albumin being a major constituent of...blood, radiolabeling of albumin with PET or SPECT isotopes may be a useful tool to evaluate vascular permeability. Kilbourn and colleagues in 1987

Bilirubin Albumin Binding and Unbound Unconjugated Hyperbilirubinemia in Premature Infants.

Science.gov (United States)

Amin, Sanjiv B; Wang, Hongyue

2018-01-01

To evaluate the associations between unbound bilirubin (UB) and total serum bilirubin (TSB), bilirubin:albumin molar ratio (BAMR), and bilirubin albumin binding affinity (Ka) as a function of gestational age (GA) in infants born at 24-33 weeks GA. In a prospective observational study, TSB and UB were measured twice daily at least 8 hours apart during the first postnatal week. Serum albumin was measured to calculate BAMR on each day. The highest UB on each day, corresponding TSB, and serum albumin were used to calculate the Ka on each day. For the 166 infants studied, peak UB significantly correlated with concomitant Ka (r = -0.44, P = .001) but not with concomitant TSB or BAMR after adjusting for GA. On multiple regression analyses, there was a significant association of concomitant Ka (-0.06, 95% CI -0.08 to -0.04, P = .0001), but not concomitant TSB or BAMR with peak UB after controlling for GA, birth weight, race, and sex. GA group was a significant effect modifier for the association between Ka and peak UB (0.03, 95% CI 0.02-0.04, P bilirubin-induced neurotoxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

Initial plasma disappearance and tissue uptake of 131I-albumin in normal rabbits

International Nuclear Information System (INIS)

Bent-Hansen, L.

1991-01-01

The simultaneous plasma disappearance curves of 131I-albumin and 125I-fibrinogen were recorded in normal rabbits for 1 hr. Using fibrinogen as a plasma reference, the disappearance curves of albumin were shown to contain two separate phases of efflux: one fast from zero to 10 min. comprising 8% of the total tracer; and one slow appearing in the interval of 10 to 60 min. containing another 9% of the tracer. Total albumin escape was analyzed to yield an initial slope of 0.024 ± 0.004 min-1, corresponding to a wholebody unidirectional albumin clearance (Cl(0)) of 0.090 ± 0.009 ml(min*100 g)-1. The distribution of efflux was assessed by biopsy uptakes using the same tracers in spleen, kidney, heart, lung, liver, intestine, skin, muscle, and brain. The disappearance curve generally reflects a biphasic pattern of uptake in peripheral tissue, predominantly by muscle and lung. The rapid phase has contributions from the fast near equilibration of liver, and intestine and skin are significant codeterminants of the slow phase. Due to their low body masses highly perfused organs such as kidney, spleen, and heart have little influence on the plasma disappearance. In accordance, the Cl(0) determined for the wholebody was higher than initial clearances found in skin (0.053 ml(min*100 g)-1) and muscle (0.054 ml(min*100 g)-1), but much lower than those found in the highly perfused organs. The initial (unidirectional) rates of peripheral albumin transfer demonstrated, ranged from 10 to 30 times higher than estimates of lymphatic return, suggesting that transcapillary albumin exchange is mediated by high-rate bidirectional diffusion. The rapid decrease of net albumin exchange rates suggests a second, highly significant barrier located within the interstitial matrix, which restricts plasma escape and reduces plasma to lymph albumin transport

LOCALIZATION OF POLYSOME-BOUND ALBUMIN AND SERINE DEHYDRATASE IN RAT LIVER CELL FRACTIONS

Science.gov (United States)

Ikehara, Yukio; Pitot, Henry C.

1973-01-01

The polysomes involved in albumin and serine dehydratase synthesis were identified and localized by the binding to rat liver polysomes of anti-rat serum albumin and anti-serine dehydratase [125I]Fab dimer and monomer. Techniques were developed for the isolation of undegraded free and membrane-bound polysomes and for the preparation of [125I]Fab monomers and dimers from the IgG obtained from the antisera to the two proteins, rat serum albumin and serine dehydratase. The distribution of anti-rat serum albumin [125I]Fab dimer in the polysome profile is in accordance with the size of polysomes that are expected to be synthesizing albumin. By direct precipitation, it has been demonstrated that nascent chains isolated from the membrane-bound polysomes by puromycin were precipitated by anti-rat serum albumin-IgG at a level of 5–6 times those released from free polysomes. Anti-rat serum albumin-[125I]Fab dimer reacted with membrane-bound polysomes almost exclusively compared to the binding of nonimmune, control [125I]Fab dimer; a significant degree of binding of anti-rat serum albumin-[125I]Fab to free polysomes was also obtained. The [125I]Fab dimer made from normal control rabbit serum does not react with polysomes from liver at all and this preparation will not interact with polysomes extracted from tissues that do not synthesize rat serum albumin. Both anti-serine dehydratase-[125I]Fab monomer and dimer react with free and bound polysomes from livers of animals fed a chow diet or those fed a high 90% protein diet and given glucagon. In the latter instance, however, it is clear that the majority of the binding occurs to the bound polysomes. Furthermore, the specificity of this reaction may be further shown by the use of kidney polysomes that do not normally synthesize serine dehydratase. When these latter polysomes are isolated, even after the addition of crude and purified serine dehydratase, no reaction with anti-serine dehydratase-Fab fragments could be

Negative permeability from random particle composites

Energy Technology Data Exchange (ETDEWEB)

Hussain, Shahid, E-mail: shussain2@qinetiq.com

2017-04-15

Artificial media, such as those composed of periodically-spaced wires for negative permittivity and split ring resonators for negative permeability have been extensively investigated for negative refractive index (NRI) applications (Smith et al., 2004; Pendry et al., 1999) [1,2]. This paper presents an alternative method for producing negative permeability: granular (or particulate) composites incorporating magnetic fillers. Artificial media, such as split-ring resonators, are designed to produce a magnetic resonance feature, which results in negative permeability over a narrow frequency range about the resonance frequency. The position of the feature is dependent upon the size of the inclusion. The material in this case is anisotropic, such that the feature is only observable when the materials are orientated in a specific direction relative to the applied field. A similar resonance can be generated in magnetic granular (particulate) materials: ferromagnetic resonance from the natural spin resonance of particles. Although the theoretical resonance profiles in granular composites shows the permeability dipping to negative values, this is rarely observed experimentally due to resonance damping effects. Results are presented for iron in spherical form and in flake form, dispersed in insulating host matrices. The two particle shapes show different permeability performance, with the magnetic flakes producing a negative contribution. This is attributed to the stronger coupling with the magnetic field resulting from the high aspect ratio of the flakes. The accompanying ferromagnetic resonance is strong enough to overcome the effects of damping and produce negative permeability. The size of random particle composites is not dictated by the wavelength of the applied field, so the materials are potentially much thinner than other, more traditional artificial composites at microwave frequencies. - Highlights: • Negative permeability from random particle composites is

Studies on albumin-131I exchange by means of the whole body radiometry in healthy individuals

International Nuclear Information System (INIS)

Bondarenko, N.I.; Kalashnikov, B.V.; Kaplan, M.A.; Bolovin, L.M.

1979-01-01

The whole body radiometry method was used to elaborate a technique of processing experimental data with subsequent calculation of the turnover indices of human serum albumin labelled by 131 I. The studies on albumin metabolism in 36 healthy men showed that in the albumin synthesis synthesis rate equal to 1455 g a day, the albumin level in the extravascular space exceeded by 2.96 times (357.1 g) that of the total albumin (120.8 g) in the plasma. About half of the plasma albumin comes from the plasma to the extravascular space daily. The turnover indices calculated by the technique applied are comparable with the data presented by other investigators. The elaborated technique is sufficiently simple and informative, makes it possible to study albumin metabolism (without taking blood samples and collecting urine) in healthy persons, and what is of special importance, in various pathological conditions

Permeability enhancement by shock cooling

Science.gov (United States)

Griffiths, Luke; Heap, Michael; Reuschlé, Thierry; Baud, Patrick; Schmittbuhl, Jean

2015-04-01

The permeability of an efficient reservoir, e.g. a geothermal reservoir, should be sufficient to permit the circulation of fluids. Generally speaking, permeability decreases over the life cycle of the geothermal system. As a result, is usually necessary to artificially maintain and enhance the natural permeability of these systems. One of the methods of enhancement -- studied here -- is thermal stimulation (injecting cold water at low pressure). This goal of this method is to encourage new thermal cracks within the reservoir host rocks, thereby increasing reservoir permeability. To investigate the development of thermal microcracking in the laboratory we selected two granites: a fine-grained (Garibaldi Grey granite, grain size = 0.5 mm) and a course-grained granite (Lanhelin granite, grain size = 2 mm). Both granites have an initial porosity of about 1%. Our samples were heated to a range of temperatures (100-1000 °C) and were either cooled slowly (1 °C/min) or shock cooled (100 °C/s). A systematic microstructural (2D crack area density, using standard stereological techniques, and 3D BET specific surface area measurements) and rock physical property (porosity, P-wave velocity, uniaxial compressive strength, and permeability) analysis was undertaken to understand the influence of slow and shock cooling on our reservoir granites. Microstructurally, we observe that the 2D crack surface area per unit volume and the specific surface area increase as a result of thermal stressing, and, for the same maximum temperature, crack surface area is higher in the shock cooled samples. This observation is echoed by our rock physical property measurements: we see greater changes for the shock cooled samples. We can conclude that shock cooling is an extremely efficient method of generating thermal microcracks and modifying rock physical properties. Our study highlights that thermal treatments are likely to be an efficient method for the "matrix" permeability enhancement of

Normal urinary albumin excretion in recently diagnosed type 1 diabetic patients

DEFF Research Database (Denmark)

Lind, B; Jensen, T; Feldt-Rasmussen, B

1989-01-01

of diabetes. Urinary albumin excretion (median and 95% confidence interval) was similar in the diabetic patients and normal control subjects (8 (6-11) vs 8 (6-11) mg 24-h-1, NS). Four diabetic patients had urinary albumin excretion in the microalbuminuric range of 30-300 mg 24-h-1. There was no significant...... difference between the two groups in urinary excretion of retinol binding protein. The distribution among the individuals of both urinary proteins was positively skewed and similar in the two groups. In conclusion, no significant differences in the urinary excretion of albumin and retinol binding protein...... were found between recently diagnosed Type 1 diabetic patients and normal subjects....

Herbal medicines that benefit epidermal permeability barrier function

Directory of Open Access Journals (Sweden)

Lizhi Hu

2015-06-01

Full Text Available Epidermal permeability barrier function plays a critical role in regulating cutaneous functions. Hence, researchers have been searching for effective and affordable regimens to enhance epidermal permeability barrier function. In addition to topical stratum corneum lipids, peroxisome proliferator-activated receptor, and liver X receptor ligands, herbal medicines have been proven to benefit epidermal permeability barrier function in both normal and diseased skin, including atopic dermatitis, glucocorticoid-induced skin damage, and UVB-damaged skin. The potential mechanisms by which herbal medicines improve the permeability barrier include stimulation of epidermal differentiation, lipid production, antimicrobial peptide expression, and antioxidation. Therefore, utilization of herbal medicines could be a valuable alternative approach to enhance epidermal permeability barrier function in order to prevent and/or treat skin disorders associated with permeability barrier abnormalities.

Cryopreservation of donkey sperm using non-permeable cryoprotectants.

Science.gov (United States)

Diaz-Jimenez, M; Dorado, J; Ortiz, I; Consuegra, C; Pereira, B; Gonzalez-De Cara, C A; Aguilera, R; Mari, G; Mislei, B; Love, C C; Hidalgo, M

2018-02-01

The aim of this study was to evaluate the effect of different concentrations of sucrose combined with bovine serum albumin (BSA), as non-permeable cryoprotectants, on donkey sperm parameters after cryopreservation, in comparison to a control extender containing glycerol. Semen from five Andalusian donkeys (n = 12) were centrifuged and resuspended with a commercial extender for equine sperm (Gent A, Minitube) adding 1% BSA and different concentrations (M, mol/l) of water-diluted sucrose: 0.05, 0.1, 0.25, 0.35 and 0.45. Thereafter, semen (n = 24) were diluted in the same base extender containing 0.25 M sucrose (S25) or glycerol (GLY, Gent B). Sperm were slowly cooled, filled in 0.5 ml straws and frozen in nitrogen vapours. Post-thaw samples were assessed for sperm motility, plasma membrane and DNA integrity and results were compared by ANOVA. In Experiment 1, sperm motility was significantly higher (P < 0.001) for S25 than the remaining treatments, and no differences were found for plasma membrane or DNA integrity. In Experiment 2, no differences were found between S25 or GLY for sperm motility and DNA integrity but plasma membrane integrity was significantly higher (P < 0.05) for S25. In conclusion, the extender with sucrose 0.25 M combined with BSA can be considered as an alternative to conventional extenders with glycerol for donkey sperm cryopreservation. Copyright © 2017 Elsevier B.V. All rights reserved.

Human Albumin Fragments Nanoparticles as PTX Carrier for Improved Anti-cancer Efficacy

Directory of Open Access Journals (Sweden)

Liang Ge

2018-06-01

Full Text Available For enhanced anti-cancer performance, human serum albumin fragments (HSAFs nanoparticles (NPs were developed as paclitaxel (PTX carrier in this paper. Human albumins were broken into fragments via degradation and crosslinked by genipin to form HSAF NPs for better biocompatibility, improved PTX drug loading and sustained drug release. Compared with crosslinked human serum albumin NPs, the HSAF-NPs showed relative smaller particle size, higher drug loading, and improved sustained release. Cellular and animal results both indicated that the PTX encapsulated HSAF-NPs have shown good anti-cancer performance. And the anticancer results confirmed that NPs with fast cellular internalization showed better tumor inhibition. These findings will not only provide a safe and robust drug delivery NP platform for cancer therapy, but also offer fundamental information for the optimal design of albumin based NPs.

Albumin infusion after reperfusion prevents gut ischemia-reperfusion-induced gut-associated lymphoid tissue atrophy.

Science.gov (United States)

Ikezawa, Fumie; Fukatsu, Kazuhiko; Moriya, Tomoyuki; Maeshima, Yoshinori; Okamoto, Koichi; Hara, Etsuko; Hiraide, Hoshio; Compher, Charlene W

2006-01-01

Our recent study clarified that gut ischemia-reperfusion (I/R) causes gut-associated lymphoid tissue (GALT) mass atrophy, a possible mechanism for increased morbidity of infectious complications after severe surgical insults. Because albumin administration reportedly reduces hemorrhagic shock-induced lung injury, we hypothesized that albumin treatment prevents GALT atrophy due to gut I/R. Male mice (n = 37) were randomized to albumin, normal saline, and sham groups. All groups underwent jugular vein catheter insertion. The albumin and normal saline groups underwent 75-minute occlusion of the superior mesenteric artery. During gut ischemia, all mice received normal saline infusions at 1.0 mL/h. The albumin group was given 5% bovine serum albumin in normal saline at 1.0 mL/h for 60 minutes after reperfusion, whereas the normal saline group received 0.9% sodium chloride at 1.0 mL/h. The sham group underwent laparotomy only. Mice were killed on day 1 or 7, and the entire small intestine was harvested. GALT lymphocytes were isolated and counted. Their phenotypes (alphabetaTCR, gammadeltaTCR, CD4, CD8, B220) were determined by flow cytometry. On day 1, the gut I/R groups showed significantly lower total lymphocyte and B cell numbers in Peyer's patches and the lamina propria than the sham group. However, the albumin infusion partially but significantly restored these cell numbers. On day 7, there were no significant differences in any of the parameters measured among the 3 groups. Albumin infusion after a gut ischemic insult may maintain gut immunity by preventing GALT atrophy.

Surface-subsurface turbulent interaction at the interface of a permeable bed: influence of the wall permeability

Science.gov (United States)

Kim, T.; Blois, G.; Best, J.; Christensen, K. T.

2017-12-01

Coarse-gravel river beds possess a high degree of permeability. Flow interactions between surface and subsurface flow across the bed interface is key to a number of natural processes occurring in the hyporheic zone. In fact, it is increasingly recognized that these interactions drive mass, momentum and energy transport across the interface, and consequently control biochemical processes as well as stability of sediments. The current study explores the role of the wall permeability in surface and subsurface flow interaction under controlled experimental conditions on a physical model of a gravel bed. The present wall model was constructed by five layers of cubically arranged spheres (d=25.4mm, where d is a diameter) providing 48% of porosity. Surface topography was removed by cutting half of a diameter on the top layer of spheres to render the flow surface smooth and highlight the impact of the permeability on the overlying flow. An impermeable smooth wall was also considered as a baseline of comparison for the permeable wall flow. To obtain basic flow statistics, low-frame-rate high-resolution PIV measurements were performed first in the streamwise-wall-normal (x-y) plane and refractive-index matching was employed to optically access the flow within the permeable wall. Time-resolved PIV experiments in the same facility were followed to investigate the flow interaction across the wall interface in sptaio-temporal domain. In this paper, a detailed analysis of the first and second order velocity statistics as well as the amplitude modulation for the flow overlying the permeable smooth wall will be presented.

Effect of Temperature on Tolbutamide Binding to Glycated Serum Albumin

Directory of Open Access Journals (Sweden)

Agnieszka Szkudlarek

2017-03-01

Full Text Available Glycation process occurs in protein and becomes more pronounced in diabetes when an increased amount of reducing sugar is present in bloodstream. Glycation of protein may cause conformational changes resulting in the alterations of its binding properties even though they occur at a distance from the binding sites. The changes in protein properties could be related to several pathological consequences such as diabetic and nondiabetic cardiovascular diseases, cataract, renal dysfunction and Alzheimer’s disease. The experiment was designed to test the impact of glycation process on sulfonylurea drug tolbutamide-albumin binding under physiological (T = 309 K and inflammatory (T = 311 K and T = 313 K states using fluorescence and UV-VIS spectroscopies. It was found in fluorescence analysis experiments that the modification of serum albumin in tryptophanyl and tyrosyl residues environment may affect the tolbutamide (TB binding to albumin in subdomain IIA and/or IIIA (Sudlow’s site I and/or II, and also in subdomains IB and IIB. We estimated the binding of tolbutamide to albumin described by a mixed nature of interaction (specific and nonspecific. The association constants Ka (L∙mol−1 for tolbutamide at its high affinity sites on non-glycated albumin were in the range of 1.98–7.88 × 104 L∙mol−1 (λex = 275 nm, 1.20–1.64 × 104 L∙mol−1 (λex = 295 nm and decreased to 1.24–0.42 × 104 L∙mol−1 at λex = 275 nm (T = 309 K and T = 311 K and increased to 2.79 × 104 L∙mol−1 at λex = 275 nm (T = 313 K and to 4.43–6.61 × 104 L∙mol−1 at λex = 295 nm due to the glycation process. Temperature dependence suggests the important role of van der Waals forces and hydrogen bonding in hydrophobic interactions between tolbutamide and both glycated and non-glycated albumin. We concluded that the changes in the environment of TB binding of albumin in subdomain IIA and/or IIIA as well as in subdomains IB and IIB influence on

Increased metabolic turnover rate and transcapillary escape rate of albumin in long-term juvenile diabetics

DEFF Research Database (Denmark)

Parving, H H; Rossing, N; Sander, E

1975-01-01

The metabolic turnover rate and transcapillary escape rate of albumin were studied with 131I-labelled human albumin in nine patients with long-term diabetes mellitus. Retinopathy was present in all patients and nephropathy in four. Plasma albumin concentration and plasma volume were reduced (P...

An albumin-oligonucleotide assembly for potential combinatorial drug delivery and half-life extension applications

DEFF Research Database (Denmark)

Kuhlmann, Matthias; Hamming, Jonas Bohn Refslund; Voldum, Anders

2017-01-01

The long blood circulatory property of human serum albumin, due to engagement with the cellular recycling neonatal Fc receptor (FcRn), is an attractive drug half-life extension enabling technology. This work describes a novel site-specific albumin double-stranded (ds) DNA assembly approach, in wh...... technology platform that offers potential combinatorial drug delivery and half-life extension applications.......The long blood circulatory property of human serum albumin, due to engagement with the cellular recycling neonatal Fc receptor (FcRn), is an attractive drug half-life extension enabling technology. This work describes a novel site-specific albumin double-stranded (ds) DNA assembly approach......, in which the 3' or 5' end maleimide-derivatized oligodeoxynucleotides are conjugated to albumin cysteine at position 34 (cys34) and annealed with complementary strands to allow single site-specific protein modification with functionalized ds oligodeoxynucleotides. Electrophoretic gel shift assays...

Active intestinal drug absorption and the solubility-permeability interplay.

Science.gov (United States)

Porat, Daniel; Dahan, Arik

2018-02-15

The solubility-permeability interplay deals with the question: what is the concomitant effect on the drug's apparent permeability when increasing the apparent solubility with a solubility-enabling formulation? The solubility and the permeability are closely related, exhibit certain interplay between them, and ongoing research throughout the past decade shows that treating the one irrespectively of the other may be insufficient. The aim of this article is to provide an overview of the current knowledge on the solubility-permeability interplay when using solubility-enabling formulations for oral lipophilic drugs, highlighting active permeability aspects. A solubility-enabling formulation may affect the permeability in opposite directions; the passive permeability may decrease as a result of the apparent solubility increase, according to the solubility-permeability tradeoff, but at the same time, certain components of the formulation may inhibit/saturate efflux transporters (when relevant), resulting in significant apparent permeability increase. In these cases, excipients with both solubilizing and e.g. P-gp inhibitory properties may lead to concomitant increase of both the solubility and the permeability. Intelligent development of such formulation will account for the simultaneous effects of the excipients' nature/concentrations on the two arms composing the overall permeability: the passive and the active arms. Overall, thorough mechanistic understanding of the various factors involved in the solubility-permeability interplay may allow developing better solubility-enabling formulations, thereby exploiting the advantages analyzed in this article, offering oral delivery solution even for BCS class IV drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

Principal permeability determination from multiple horizontal well tests

Energy Technology Data Exchange (ETDEWEB)

Economides, M. [Texas A and M Univ., TX (United States); Munoz, A.; Ehlig-Economides, C.

1998-12-31

A method for obtaining principal permeability magnitudes and direction that requires only the linear flow regime from transient tests in three horizontal wells oriented in three distinct and arbitrary directions, is described. Well design optimization strategies require knowledge of both the principal permeability orientation as well as the horizontal permeability magnitudes. When the degree of horizontal permeability anisotropy (i.e. permeability in the bedding plane with respect to direction) is significant, the productivity of a long horizontal well will depend greatly on its direction, especially when the well is first brought into production. Productivities have been found to deviate substantially among wells in the same reservoir and this deviation has been attributed to differences in well orientation. In view of this fact, measuring permeability anisotropy becomes a compelling necessity. The success of the proposed method is illustrated by a case study in which the principal permeability magnitudes and direction from three wells were used to predict the productivity of a fourth well within 10 per cent. Use of the computed principal permeabilities from the case study, it was possible to forecast the cumulative production to show the significance of well trajectory optimization on the discounted cash flow and the net present value. 20 refs., 3 figs.

Reduced Albumin Dosing During Large-Volume Paracentesis Is Not Associated with Adverse Clinical Outcomes.

Science.gov (United States)

Johnson, Kara B; Mueller, Jessica L; Simon, Tracey G; Zheng, Hui; King, Lindsay Y; Makar, Robert S; Gervais, Debra A; Chung, Raymond T

2015-07-01

LVP is used to manage diuretic-resistant ascites in cirrhotic patients. Albumin administration prevents complications including acute kidney injury and paracentesis-induced circulatory dysfunction, but the optimal dose is unclear. We sought to assess adherence to guidelines enacted in July 2011 at our center for reducing the albumin dose administered at large-volume paracentesis (LVP) and evaluate the cost and rate of complications of LVPs before and after guideline enactment. All LVPs performed on cirrhotic patients in our center's Department of Radiology between July 2009 and January 2014 were studied. Outcomes included adherence to guidelines, LVP complications, and administered albumin cost. Groups were compared using Student's t tests for continuous data and Chi-square or Fisher's exact tests for categorical data. A repeated measurements model accounted for patients with multiple LVPs. Of the 935 LVPs, 288 occurred before guideline implementation (group 1) and 647 occurred after (group 2). The mean dose of albumin administered was 13.7 g/L of ascites removed in group 1 versus 10.3 g/L in group 2 (p albumin administration and associated cost savings was still observed. There was no increase in LVP-related complications after guideline implementation or in the adherent group, suggesting that albumin dose can be safely reduced. Future efforts should be directed at enhancing guideline adherence and potentially further reducing albumin dosing.

Amino acid substitutions in genetic variants of human serum albumin and in sequences inferred from molecular cloning

International Nuclear Information System (INIS)

Takahashi, N.; Takahashi, Y.; Blumberg, B.S.; Putnam, F.W.

1987-01-01

The structural changes in four genetic variants of human serum albumin were analyzed by tandem high-pressure liquid chromatography (HPLC) of the tryptic peptides, HPLC mapping and isoelectric focusing of the CNBr fragments, and amino acid sequence analysis of the purified peptides. Lysine-372 of normal (common) albumin A was changed to glutamic acid both in albumin Naskapi, a widespread polymorphic variant of North American Indians, and in albumin Mersin found in Eti Turks. The two variants also exhibited anomalous migration in NaDodSO 4 /PAGE, which is attributed to a conformational change. The identity of albumins Naskapi and Mersin may have originated through descent from a common mid-Asiatic founder of the two migrating ethnic groups, or it may represent identical but independent mutations of the albumin gene. In albumin Adana, from Eti Turks, the substitution site was not identified but was localized to the region from positions 447 through 548. The substitution of aspartic acid-550 by glycine was found in albumin Mexico-2 from four individuals of the Pima tribe. Although only single-point substitutions have been found in these and in certain other genetic variants of human albumin, five differences exist in the amino acid sequences inferred from cDNA sequences by workers in three other laboratories. However, our results on albumin A and on 14 different genetic variants accord with the amino acid sequence of albumin deduced from the genomic sequence. The apparent amino acid substitutions inferred from comparison of individual cDNA sequences probably reflect artifacts in cloning or in cDNA sequence analysis rather than polymorphism of the coding sections of the albumin gene

Role of permissive hypotension, hypertonic resuscitation and the global increased permeability syndrome in patients with severe hemorrhage: adjuncts to damage control resuscitation to prevent intra-abdominal hypertension.

Science.gov (United States)

Duchesne, Juan C; Kaplan, Lewis J; Balogh, Zsolt J; Malbrain, Manu L N G

2015-01-01

Secondary intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are closely related to fluid resuscitation. IAH causes major deterioration of the cardiac function by affecting preload, contractility and afterload. The aim of this review is to discuss the different interactions between IAH, ACS and resuscitation, and to explore a new hypothesis with regard to damage control resuscitation, permissive hypotension and global increased permeability syndrome. Review of the relevant literature via PubMed search. The recognition of the association between the development of ACS and resuscitation urged the need for new approach in traumatic shock management. Over a decade after wide spread application of damage control surgery damage control resuscitation was developed. DCR differs from previous resuscitation approaches by attempting an earlier and more aggressive correction of coagulopathy, as well as metabolic derangements like acidosis and hypothermia, often referred to as the 'deadly triad' or the 'bloody vicious cycle'. Permissive hypotension involves keeping the blood pressure low enough to avoid exacerbating uncontrolled haemorrhage while maintaining perfusion to vital end organs. The potential detrimental mechanisms of early, aggressive crystalloid resuscitation have been described. Limitation of fluid intake by using colloids, hypertonic saline (HTS) or hyperoncotic albumin solutions have been associated with favourable effects. HTS allows not only for rapid restoration of circulating intravascular volume with less administered fluid, but also attenuates post-injury oedema at the microcirculatory level and may improve microvascular perfusion. Capillary leak represents the maladaptive, often excessive, and undesirable loss of fluid and electrolytes with or without protein into the interstitium that generates oedema. The global increased permeability syndrome (GIPS) has been articulated in patients with persistent systemic inflammation failing

Permeability Tests on Eastern Scheldt Sand

DEFF Research Database (Denmark)

Jakobsen, Kim Parsberg

on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Eastern Scheldt Sand. The permeability is determined by use of a falling head apparatus. Finally the test results are briefly summarised and a relationship between......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

Thermodynamic parameters for binding of fatty acids to human serum albumin

DEFF Research Database (Denmark)

Pedersen, A O; Honoré, B; Brodersen, R

1990-01-01

Binding of laurate and myristate anions to human serum albumin has been studied over a range of temperatures, 5-37 degrees C, at pH 7.4. The binding curves indicate that the strength of binding of the first few molecules of fatty acid to albumin (r less than 5) decreases with increasing temperatu...

Plasma volume, intravascular albumin and its transcapillary escape rate in patients with extensive skin disease

DEFF Research Database (Denmark)

Parving, H H; Worm, A M; Rossing, N

1976-01-01

Plasma volume and plasma concentration and transcapillary escape rate of albumin (TER alb), i.e. the fraction of intravascular mass of albumin that passes to the extravascular space per unit time, were determined using 125I-labelled human albumin in eight patients with extensive skin disease....... Plasma volume and plasma albumin concentration were reduced (P less than 0-05). Thus the intravascular albumin mass was moderately decreased to an average of 0-55 +/- 0-06 (s.d.) g/cm height compared with a normal mean value of 0-77 +/- 0-07 (s.d.) g/cm. This 29% decrease is statistically significant (P...... less than 0-001). The transcapillary escape rate of albumin (TER alb) was significantly elevated, mean 8-6 +/- 1-1 (s.d.) % X h-1, as compared to normal subjects, mean 5-6 +/- 1-1 (s.d.) % X h-1, (+54%, P less than 0-001). The same patients were studied again after a 1-week treatment with prednisone...

Effect of Processing Delay and Storage Conditions on Urine Albumin-to-Creatinine Ratio.

Science.gov (United States)

Herrington, William; Illingworth, Nicola; Staplin, Natalie; Kumar, Aishwarya; Storey, Ben; Hrusecka, Renata; Judge, Parminder; Mahmood, Maria; Parish, Sarah; Landray, Martin; Haynes, Richard; Baigent, Colin; Hill, Michael; Clark, Sarah

2016-10-07

Because there is substantial biologic intraindividual variation in albumin excretion, randomized trials of albuminuria-reducing therapies may need multiple urine samples to estimate daily urinary albumin excretion. Mailing spot urine samples could offer a convenient and cost-effective method to collect multiple samples, but urine albumin-to-creatinine ratio stability in samples stored at ambient temperatures for several days is unknown. Patients with kidney disease provided fresh urine samples in two tubes (with and without boric acid preservative). Reference aliquots from each participant were analyzed immediately, whereas remaining aliquots were subject to different handling/storage conditions before analysis, including delayed processing for up to 7 days at three different storage temperatures (4°C, 18°C, and 30°C), multiple freeze-thaw cycles, and long-term frozen storage at -80°C, -40°C, and -20°C. We calculated the mean percentage change in urine albumin-to-creatinine ratio for each condition, and we considered samples stable if the 95% confidence interval was within a ±5% threshold. Ninety-three patients provided samples with detectable albuminuria in the reference aliquot. Median (interquartile range) urine albumin-to-creatinine ratio was 87 (20-499) mg/g. The inclusion of preservative had minimal effect on fresh urine albumin-to-creatinine ratio measurements but reduced the changes in albumin and creatinine in samples subject to processing delay and storage conditions. The urine albumin-to-creatinine ratio was stable for 7 days in samples containing preservative at 4°C and 18°C and 2 days when stored at 30°C. It was also stable in samples with preservative after three freeze-thaw cycles and in frozen storage for 6 months at -80°C or -40°C but not at -20°C. Mailed urine samples collected with preservative and received within 7 days if ambient temperature is ≤18°C, or within 2 days if the temperature is higher but does not exceed 30°C, are

Damage-induced permeability changes around underground excavations

International Nuclear Information System (INIS)

Coll, C.

2005-07-01

The storage of nuclear waste in deep geological formations is now considered more and more as a potential solution. During excavation, a disturbed zone develops in which damaging can be important and which can lead eventually to the failure of the rock. Fluid flow and permeability in the rock mass can be significantly modified producing a possible security risk. Our work consisted in an experimental study of the hydro-mechanical coupling of two argillaceous rocks: Boom clay (Mol, Belgium) and Opalinus clay (Mont-Terri, Switzerland). Triaxial tests were performed in a saturated state to study the permeability evolution of both clays with isotropic and deviatoric stresses. Argillaceous rocks are geo-materials with complex behaviour governed by numerous coupled processes. Strong physico-chemical interactions between the fluid and the solid particles and their very low permeability required the modification of the experimental set up. Moreover, specific procedures were developed to measure permeability and to detect strain localisation in shear bands. We show that for Boom Clay, permeability is not significantly influenced by strain localisation. For Opalinus clay, fracturing can induce an increase of the permeability at low confining pressure. (author)

Long-term Metal Performance of Three Permeable Pavements