Serum Albumin In Blood Research Articles

Study Of Cardic Valvular Calcification In ESRD Patients On Regular Hemodialysis (A Single Center Study)

Cardiac valve calcification are common among patients with chronic kidney disease (CKD). Risk factors include alterations in calcium and phosphorus metabolism, elevated calcium phosphorus product and persistent elevations in plasma parathyroid hormone (PTH). Echocardiography is a simple and inexpensive method for detection of valvular calcifications as suggested by KDIGO guidelines. 60 Patients on regular HD constituted group A (36 males and 24 females) and 25 healthy volunteers constituted group B. Group A was subdivided into: Group I: 21 patients with no valvular calcification, group 2: 26 patients with aortic valve calcification and group 3: 13 patients with aortic and mitral valve calcification. For all, the following was done: clinical examination, serum Ca, serum P, serum albumin, serum creatinine, BUN and PTH level in blood. M-mode echo cardiography was done for all. Age, duration of dialysis and duration of 1ry kidney disease was higher in group 2 and 3 compared to group 1 (p = 0.0001). Calcium was higher in group 2 than group 1 (p = 0.09) and group 3 (p = 0.004) than group I phosphorus was higher in group 2 and 3 than group 1 (P = 0.001). P was higher in group 3 than group 2 (p = 0.0001). Ca x P was higher in group 2 and 3 than group 1 (p = 0.0001), in group 3 than group 2 (p = 0.01) PTH was higher in group 1 than group 2 (p = 0.06). Cardiac dysfunction by echocardiography was least in group 1, increasing in group 2 and being highest in group 3. It was found that calcified valve groups has taken higher doses of Calcium and Vitamin D3 . We have to take care on prescribing Ca and vitamin D3 to ESRD patients on regular HD.

Albinterferon-alfa 2b: a new treatment option for hepatitis C

Importance of the field: HCV infection affects 180 million people worldwide. Standard therapy combines weekly injections of pegIFN and daily ribavirin (RBV). Albinterferon (albIFN)-α2b is the most advanced in the development of an IFN-based compound.Areas covered in this review: The rationale for albIFN-α2b is to combine IFN-α antiviral activity with prolonged presence of human serum albumin in human blood. Initial experimental studies on albIFN-α2b were published in 2002. This review provides results of preclinical and subsequent clinical trials. Results of two Phase III clinical trials were presented in 2009 and will be published shortly.What the reader will gain: This review discusses the current status of knowledge on the efficacy and safety of albIFN-α2b. Phase III clinical trials demonstrated comparable efficacy of albIFN-α2b given every 2 weeks to weekly pegIFN-α2a, both in combination with RBV. However, the most promising seems to be every 4 weeks dosage.Take home message: Treatment with albIFN-α2b combined with RBV can provide comparable efficacy with the current standard of care medication with a reduced number of injections. Lower frequency of some adverse events and improved quality of life can be expected in patients receiving albIFN-α2b every 4 weeks.

Influence of the Galloyl Moiety in Tea Catechins on Binding Affinity for Human Serum Albumin

The major catechins of green tea extract are (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg). Recent research has indicated that catechins form complexes with human serum albumin (HSA) in blood, and differences in their binding affinity toward HSA are believed to modulate their bioavailability. In this study, we kinetically investigated the interaction between the catechins and HSA immobilized on a quartz-crystal microbalance (QCM). The association constants obtained from the frequency changes of QCM revealed interactions of ECg and EGCg with HSA that are 100 times stronger than those of EC and EGC. Furthermore, comparisons of these catechins by native-gel electrophoresis/blotting with redox-cycling staining revealed that, in a phosphate buffer, ECg and EGCg have a higher binding affinity toward HSA than EC and EGC. These observations indicate that catechins with a galloyl moiety have higher binding affinities toward HSA than catechins lacking a galloyl moiety.

Covalent Binding of the Flavonoid Quercetin to Human Serum Albumin

Quercetin is an abundant flavonoid in the human diet with numerous biological activities, which may contribute to the prevention of human disease but also may be potentially harmful. Quercetin is oxidized in cells to products capable of covalently binding to cellular proteins, a process that may be important for its biological activities. In the present study, using radiolabeled drug and quantifying the products after electrophoretic separation, proteins to which oxidized quercetin is binding irreversibly were identified. The binding of quercetin to human serum albumin (HSA) in human blood and the effect of stimulation of neutrophilic myeloperoxidase on this binding were also measured. The in vitro binding of quercetin to eight proteins in the presence of catalytic amounts of horseradish peroxidase and hydrogen peroxide was highly selective for HSA. For all proteins the binding was dramatically decreased by reduced L-glutathione. In the blood samples, the release of neutrophilic myeloperoxidase by phorbol ester caused a 3-fold increase in the binding of quercetin to HSA. This study shows that quercetin in the presence of peroxidase/hydrogen peroxide covalently links to proteins with a particularly high affinity for HSA and that this also may occur in vivo after exposure to quercetin. This provides further insights into the complex behavior of this major dietary flavonoid.

Determination of Serum Albumin in Blood by Constant-Current Coulometry Using Electrochemically Generated Oxidizers

A method is developed for the determination of human serum albumin by constant-current coulometry using electrochemically generated oxidizers. It is found that human serum albumin interacts with electrochemically generated bromine and iodine at a ratio of 1 : 73 and 1 : 64, respectively. Milligrams of human serum albumin were determined in model solutions with RSD = 1–2%. A procedure is proposed for the determination of serum albumin in human blood.

Albumin leakage into the brain and wireless-communication radiation

A series of reports from Lund, Sweden, based on observed leakages of endogenous serum albumin in blood, suggested that repeated exposure to microwave radiation from GSM cellular telephones could alter the permeability of the blood-brain barrier at SARs that were well below the maximum permissible level for cellular telephones. While an effort to confirm had failed at SARs of 0.3-1.5 W/kg, it had confirmed extravasation of serum albumin at 7.5 W/kg: a level about four times greater than the maximum permissible level for cellular telephones. Currently, there is considerable interest from several laboratories around the world in replicating the reported occurrence of abnormal neurons in the rat brain resulting from leakage of endogenous serum albumin.

S-nitrosation of Ca(2+)-loaded and Ca(2+)-free recombinant calbindin D(28K) from human brain.

Calbindin D(28K) is noted for its abundance and specific distribution in mammalian brain and sensory neurons. It can bind three to five Ca(2+) ions and may act as a Ca(2+) buffer to maintain intracellular Ca(2+) homeostasis, but its exact role is still unknown. In the present study, mass spectrometric analysis reveals that the five cysteine residues in recombinant human brain calbindin D(28K) (rHCaBP) are derivatized with N-ethylmaleimide, consistent with the determination of 5.3 +/- 0.4 and 4.7 +/- 0.4 free thiols in the protein using the thiol-specific reagents 5,5'-dithiobis(2-nitrobenzoic acid) and 5-(octyldithio)-2-nitrobenzoic acid, respectively. The results of UV-vis and circular dichroism absorption, intrinsic fluorescence, and mass spectrometry measurements indicate that both Ca(2+)-loaded (holo) and Ca(2+)-free (apo) rHCaBP are S-nitrosated by S-nitrosocysteine (CysNO). The number of cysteine residues S-nitrosated in holorHCaBP and aporHCaBP are 2.6 +/- 0.05 and 3.4 +/- 0.09, respectively, as determined by the Saville assay. HolorHCaBP also undergoes S-nitrosation at one to three cysteine residues when exposed to S-nitrosoglutathione (GSNO), and Cys100 was found to be an S-nitrosation site by peptide mass mapping. Treatment of holorHCaBP with free NO resulted in a mass increase of 59 +/- 2 Da, corresponding to two NO adducts. Since up to four cysteine residues can be S-nitrosated in rHCaBP, it is proposed that the protein may act as a NO buffer or reservoir in the brain in a manner similar to serum albumin in blood. It is significant in this context that rHCaBP is found coexistent with nitric oxide synthase in cerebellum and that S-nitrosation varies with Ca(2+) binding, with S-nitrosation occurring to a greater extent in aporHCaBP than in the holoprotein. Furthermore, exposure of rHCaBP to either CysNO or GSNO also leads to rapid S-thiolation of Cys187. We demonstrate here for the first time that intrinsic protein fluorescence is a sensitive probe of protein S-nitrosation. This is due to efficient Förster energy transfer (R(0) approximately 17 A) between tryptophan donors and S-nitrosothiol acceptors.

Fluorescence properties of albumin blue 633 and 670 in plasma and whole blood.

We have determined the fluorescence characteristics of two long wavelength dyes, albumin blue 633 (AB633) and 670 (AB670), in plasma and blood to evaluate the possibility of making direct fluorescence sensing measurements in blood. Using binding and lifetime measurements we were also able to show that these dyes bind selectively to human serum albumin (HSA) in plasma and blood. By measuring changes in the mean lifetime of AB670 with changes in the HSA concentration, we showed that lifetime-based sensing can be used to monitor HSA concentrations using these albumin blue dyes. Anisotropy measurements for AB633 and AB670 in plasma and blood revealed high anisotropy values for these dyes in these media. Exploiting these high anisotropies, we were also able to determine HSA concentrations in plasma and blood mimics using changes in AB670 anisotropy with HSA concentration. These results show that, apart from being able to make fluorescence measurements directly in plasma and blood, it is possible to sense directly for specific plasma/blood components using fluorescent probes that bind preferentially to them.

The Effect of Serum Albumin on the Aggregation State and Toxicity of Amphotericin B

Studies have shown that the dose‐limiting toxicity of amphotericin B (AmB), a key drug for systemic mycoses, depends on its self‐aggregation state. In a step toward understanding the various factors in blood mediating the toxicity of AmB, we have investigated the effect of serum albumin, the most abundant plasma protein, on the aggregation state of AmB using absorption spectroscopy. The critical aggregation concentration (CAC) of AmB, which coincides with its concentration at the onset of toxicity (hemolysis), was 1.1 μM, but rose in proportion to the level of serum albumin (1.0 to 4.0% w/v). The CAC of AmB was 8.0 μM at 4.0% w/v serum albumin, which is considerably higher than peak therapeutic levels of AmB in plasma (i.e., 2.0 μM). Serum albumin (4.0% w/v) lowered the degree of aggregation of AmB (size of aggregates) above the CAC and increased its solubility. The results suggest that serum albumin attenuates the toxicity of AmB at a membrane level by affecting its aggregation state. In this way, serum albumin in blood may balance deleterious effects of AmB mediated by serum low‐density lipoproteins. ©2000 Wiley‐Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 89: 1589–1593, 2000

Monitoring and antibacterial treatment for postoperative bacterial overgrowth in Crohn's disease.

Bacterial overgrowth sometimes complicates the clinical course of Crohn's disease and may lead to inappropriate treatment. To clarify the effect of antibiotic therapy, we monitored the hydrogen concentration in expiratory breath after fasting. We evaluated 18 patients (15 males; median age, 32.7; range, 22.3-60 years) for postoperative bacterial overgrowth symptoms and for intestinal dilation by plain abdominal x-ray. Five patients had ileitis and 13 patients had ileocolitis. Various intestinal resections were performed in all, and strictureplasties were done at the same time in 13 patients. The median postoperative period was 10.2 (range, 1.2-102) months. Nine patients, who had symptoms such as bloating, nausea, vomiting, or pain, were classified as the symptomatic group, whereas nine other patients, who had no symptoms, were classified as the symptom-free group. Sixteen patients who had undergone intestinal resections for noninflammatory bowel disease served as the control group. After overnight fasting, hydrogen concentration in end-expiration, breath was measured with gas chromatography. At the same time clinical examinations of white blood cell count, hemoglobin, total protein, serum albumin, iron, sialic acid, and C-reactive protein in the peripheral blood were performed. To assess the effect of antibacterial treatment, changes in symptoms were assessed in eight patients who received antibacterial treatment. Hydrogen concentration was measured repeatedly before and after treatment in six patients. The symptomatic group had an expiratory hydrogen concentration level significantly higher (median, 40; range, 20-139 ppm) than the control group (median, 3; range, 1-6 ppm) and the symptom-free group (median, 4; range, 1-10 ppm). After the antibiotic treatment the symptoms were improved in all of the patients, and the hydrogen concentration level was significantly reduced (median, 4.5; range, 2-13 ppm). Antibacterial treatment was useful in the postoperative patients whose assessments were complicated by bacterial overgrowth. Using a hydrogen breath test, bacterial overgrowth was effectively monitored and managed, effecting a change in clinical symptoms.

High prevalence of hypophosphataemia amongst patients with infectious diseases. A retrospective study.

To describe the prevalence of hypophosphataemia amongst all patients treated during 1993 for infectious diseases. The associations between serum C-reactive protein, serum albumin and white blood cells in blood were studied amongst hypophosphataemic patients. Comparisons were made according to the severity of infection. A retrospective study of the prevalence of hypophosphataemia, and a case-control study amongst a subgroup of patients. The Department of Infectious Diseases, University Hospital, Umeå, Sweden. For the prevalence study all 967 patients (449 women and 518 men) treated during 1993 were included. In the case-control study, 108 cases, with serum phosphate < or =0.64 mmol L(-1), 216 age-and sex-matched controls with serum phosphate >0.82 mmol L(-1) (men) and >0.86 mmol L(-1) (women), respectively, were included. In 402 of 967 patients (42%) at least one serum phosphate value was below the reference level. Hypophosphataemia was found in 573 of 1966 blood samples (29%). Severe hypophosphataemia (<0.30 mmol L(-1)) was seen in 1.2% of the patients (0.9% of blood samples). The prevalence of hypophosphataemia was higher amongst women than amongst men. In the case-control study, the serum C-reactive protein and the number of white blood cells was higher amongst the cases compared with the controls (124 vs. 94 mg L(-1) and 11.4 vs. 9.3 cells/L x10(9), respectively). The multiple logistic regression showed a 4-fold higher risk of having low serum phosphate in patients with severe infection, compared with mild infections. None of the other variables (albumin, days of hospital stay or white blood cells in blood) increased the risk for hypophosphataemia. The high prevalence of low serum phosphate levels and the increased risk of having low levels in severe infections shown in this study needs further attention.

Binding of disodium cromoglycate to human serum albumin

The binding of several benzopiranone derivatives to human serum albumin was determined. The antiallergic drug disodium cromoglycate binds weakly to serum albumin. However, its precursors, chromones of smaller size, were able to bind in a hydrophobic pocket in the protein, and are carried by serum albumin in blood.

Entry of the synthetic ACTH(4–10) analogue into the rat brain following intravenous injection

In view of known central effects of N-terminal ACTH fragments, a possibility of their entry into the brain was studied. Rat blood and brain extracts after intravenous injection of the tritiated synthetic ACTH(4–10) analogue, Met-Glu-His-Phe-Pro-Gly-Pro, were subjected to a high-performance liquid chromatographic analysis. At two time points the labelled peptide was detected in brain extracts. The brain to blood ratios of peptide content in brain and blood were found to be significantly higher than those calculated for a distribution of labelled bovine serum albumin in rat brain capillaries and blood. This strongly suggests that this peptide penetrates into the brain tissues, its quantity not exceeding 0.01% of dose injected. Peptide diffusion through the vascular epithelium of brain capillaries could account for the data obtained.

Determination of endogenous serum proteins in normal and oedematous brain tissue of cat by rocket and crossed immunoelectrophoresis

A quantitative method for determination of endogenous serum proteins has been established and tested in an experimental model of peritumoural brain oedema in cats. Rocket and crossed immunoelectrophoresis were applied for determination of total serum proteins, albumin, IgG and haemoglobin in blood and brain homogenates. Modifications such as the use of non-ionic detergents and of antisera with different specificity were established for each antigen under investigation. The content of total serum proteins, albumin and IgG was substantially higher in tumour and peritumoural brain tissue than in the non-oedematous brain. The measurement of haemoglobin allowed the calculation of blood volume and, in consequence, the differentiation between intra- and extravascular serum proteins. The results are in line with earlier measurements obtained by different analytical methods and demonstrate that the present technique provides a reliable approach for the quantitative assessment of serum protein extravasation.

Protein-synthesizing function of the liver in rabbits with experimental myocardial infarction

The content of serum albumin in rabbit blood was found to be lowered within the first day after reproduction of experimental myocardial infarction. The rate and the level of translation of endogenous mRNA were studied in cell-free systems from normal rabbit liver and 6-12-24 h after experimental myocardial infarction. The decrease of the total protein synthesis in the crude cell-free system from the liver of experimental animals was shown to depend on the lack of energy supply rather than on the reduced activity of the protein-synthesizing apparatus. The relative drop of protein synthesis in the cell-free system with saturating concentration of ATP, GTP and creatine phosphate is likely to be connected with a decrease in the proportion of membrane-bound polysomes.

Multi-origins of milk serum albumin in the lactating goat

L-[U- 14C]Leucine was infused into the right-hand mammary glands of lactating goats. Milk from both glands of the animals was sampled at intervals for 36 h. After 3 h the specific activity of milk serum albumin from the infused glands was more than six times that from the non-infused glands. The specific activity of milk serum albumin was considerably lower than that of α-lactalbumin or β-lactoglobulin which are exclusively synthesized by mammary secretory cells. Following the intravenous injection of 125I-labeled serum albumin, maximum specific activity of this protein appeared in milk in 12 h. The specific activity of serum albumin in milk attained no more than 45% of the specific activity of the serum albumin in blood. It is concluded that milk serum albumin has multiple origins and that a portion of it, at least (10–20%), is made in the mammary gland.

Indicator dilution measurements of flow parameters in curved tubes and branching networks

An experimental investigation has been made of the application of the indicator-dilution bolus-injection technique to measure flow rate, mean transit time and vessel volume with steady flow. Measurements were made with 131I in 2N KCl, and 131I-human serum albumin in isotonic saline, plasma and whole blood under laminar flow conditions up to a Reynolds' number of 460.