Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cardiac markers are more likely to be elevated in dialysis patients than in patients with renal failure not on dialysis. In this study, 31 patients (20 males, 11 females) undergoing chronic haemodialysis were enrolled. The effect of haemodialysis on cardiac troponin T (cTnT), I (cTnI), creatine kinase MB (CKMB) mass, CKMB activity and myoglobin assays was assessed by comparing pre- and post-haemodialysis determinations. After correcting for haemoconcentration, significant differences were observed (mean +/- SEM, pre- vs post-dialysis) for myoglobin (178.9 +/- 19.3 vs 225.0 +/- 28.4 ng/ml; p=0.006) for cTnT (0.111 +/- 0.028 vs 0.148 +/- 0.037 ng/ml; p=0.004), for CKMB mass (2.75 +/- 0.37 vs 2.59 +/- 0.37 ng/ml; p=0.000) and CKMB activity (14.8 +/- 0.9 vs 13.1 +/- 0.9 U/l; p=0.000) assays. Our study questions the reliability of cardiac markers in dialysis patients and suggests that the clinical threshold value and diagnostic efficiency of each assay needs to be validated. Although these differences exceeded clinical threshold values in only a few patients, serum markers of myocardial damage in dialysis patients should be interpreted with caution.
 ...
PMID:Acute effect of haemodialysis on serum markers of myocardial damage. 1213 38

In developed countries where meat is an important constituent of the diet, much of the dietary iron is in the heme-iron form as hemoglobin and myoglobin. Heme-iron is absorbed more efficiently than inorganic iron by the human intestine. Thus, it is important to know how the dose of heme-iron affects iron absorption. The purpose of this study was to establish the dose-effect of heme-iron on the percentage and absolute amount of iron absorbed. Twenty-seven healthy women (28- to 50-y-old) were selected to participate in two iron absorption studies. Through the use of iron isotopes ((59)Fe and (55)Fe), the studies were performed to characterize the dose-response curve of non-heme-iron absorption (ferrous sulfate), and to establish the dose-response curve of heme-iron absorption (hemoglobin). The labeled hemoglobin was prepared by use of red blood cells from rabbits. The geometric means (+/-1 SEM range) of non-heme iron absorbed were 0.2 (0.2-0.3), 1.2 (1.0-1.5), 6.7 (5.7-8.0) and 13.0 (11.5-14.6) mg of iron for doses of 0.5, 5, 50 and 100 mg of iron as ferrous sulfate, respectively; and 0.1 (0.1-0.2), 0.4 (0.3-0.4), 2.2 (2.0-2.4) and 2.2 (1.7-3.0) mg of iron for doses of 0.5, 3, 15 and 30 mg of heme-iron as hemoglobin, respectively. The fitted curves for heme and non-heme iron differed (P < 0.04). These results strongly suggest that the heme-iron absorption pathway is saturable.
 ...
PMID:Heme-iron absorption is saturable by heme-iron dose in women. 1284 Jan 81

A comparative study was performed on strong cation-exchangers to investigate the pH dependence, efficiency, binding strength, particle size distribution, static and dynamic capacity, and SEM pictures of chromatographic resins. The resins tested included: SP Sepharose XL, Poros 50 HS, Toyopearl SP 550c, SP Sepharose BB, Source 30S, TSKGel SP-5PW-HR20, and Toyopearl SP 650c. Testing was performed with four different proteins: anti-FVII Mab (IgG), aprotinin, lysozyme, and myoglobin. Dependence of pH on retention was generally very low for proteins with high pI. An unexpected binding at pH 7.5 of anti-FVII Mab with pI < 7.5 was observed on several resins. Efficiency results show the expected trend of higher dependence of the plate height with increasing flow rate of soft resins compared to resins for medium and high-pressure operation. Determination of particle size distribution by two independent methods, Coulter counting and SEM, was in very good agreement. The mono-dispersed nature of Source 30S was confirmed. Binding to cation-exchange resins as a function of ionic strength varies depending on the specific protein. Generally, binding and elution at high salt concentration may be performed with Toyopearl SP 550c and Poros 50 HS, while binding and elution at low salt concentration may be performed with Toyopearl SP 650c. A very high binding capacity was obtained with SP Sepharose XL. Comparison of static capacity and dynamic capacity at 10% break-through shows in general approximately 50-80% utilisation of the total available capacity during chromatographic operation. A general good agreement was obtained between this study and data obtained by others. The results of this study may be used for selection of resins for testing in process development. The validity of experiments and results with model proteins were tested using human insulin precursor in pure state and in real feed-stock on Toyopearl SP 550c, SP Sepharose BB, and Toyopearl SP 650c. Results showed good agreement with experiments with model proteins.
 ...
PMID:Comparison of chromatographic ion-exchange resins. III. Strong cation-exchange resins. 1511 17

A comparative study was performed on heparin resins and strong and weak cation exchangers to investigate the pH dependence, efficiency, binding strength, particle size distribution, static and dynamic capacity, and scanning electron microscopy pictures of chromatographic resins. The resins tested include: Heparin Sepharose FF, SP Sepharose FF, CM Sepharose FF, Heparin Toyopearl 650 m, SP Toyopearl 650 m, CM Toyopearl 650 m, Ceramic Heparin HyperD M, Ceramic S HyperD 20, and Ceramic CM HyperD F. Testing was performed with four different proteins: anti-FVII Mab (IgG), aprotinin, lysozyme, and myoglobin. Dependence of pH on retention was generally very low for proteins with high isoelectric point (pI), though some decrease of retention with increasing pH was observed for CM Ceramic HyperD F and S Ceramic HyperD 20. Binding of anti-FVII Mab with pI < 7.5 was observed on several resins at pH 7.5. Efficiency results show the expected trend of increasing dependence of the plate height with increasing flow rate of Ceramic HyperD resins followed by Toyopearl 650 m resins and the highest flow dependence of the Sepharose FF resins corresponding to their pressure resistance. Determination of particle size distribution by two independent methods, coulter counting and SEM, was in good agreement. Binding strength of cation-exchange resins as a function of ionic strength varies depending on the protein. Binding and elution at high salt concentration may be performed with Ceramic HyperD resins, while binding and elution at low salt concentration may be performed with model proteins on heparin resins. Employing proteins with specific affinity for heparin, a much stronger binding is observed, however, some cation exchangers may still be good substitutions for heparin resins. Dynamic capacity at 10% breakthrough compared to static capacity measurements and dynamic capacity displays that approximately 40-80% of the total available capacity is utilized during chromatographic operation depending on flow rate. A general good agreement was obtained between results of this study and data obtained by others. Results of this study may be used in the selection of resins for testing during protein purification process development.
 ...
PMID:Comparison of chromatographic ion-exchange resins IV. Strong and weak cation-exchange resins and heparin resins. 1584 84

This study aimed to investigate if old men were more susceptible than young men to muscle damage induced by exercise consisting of repeated-lengthening muscle actions. The responses to a bout of eccentric exercise were compared between 10 young (mean age +/- SEM = 19.4 +/- 0.4 y) and 10 old (70.5 +/- 1.5 y) men. All subjects performed 6 sets of 5 lengthening actions of the left elbow flexors at a range of 90 degrees from an elbow flexed (90 degrees ) to an extended (180 degrees ) position in 5 s using a dumbbell massed at 40% maximal isometric strength (MVC) at an elbow joint angle of 90 degrees . Changes in MVC, range of motion (ROM), upper arm circumference (CIR), muscle soreness (DOMS), plasma creatine kinase activity (CK), and myoglobin (Mb) concentration over 7-10 d following exercise were compared between groups by 2-way repeated measures analysis of variance (ANOVA). Significant differences between groups were evident at baseline for ROM (significantly smaller for the older group) and CIR (significantly larger for the older group), but not for MVC and other measures. Contrary to the hypothesis, the young group showed significantly larger decreases in MVC and ROM and larger increases in circumference, DOMS, CK activity, and Mb con centration than those of the old group. These results suggest that muscle damage is not necessarily greater in old versus young men following voluntary eccentric exercise. It may be that physiological changes that occur with ageing, including a decrease in ROM, reduce damaging stress to muscles during lengthening muscle actions.
 ...
PMID:Comparison between old and young men for changes in makers of muscle damage following voluntary eccentric exercise of the elbow flexors. 1677 Mar 48

The design, synthesis and properties of a new class of enzyme/DNA/inorganic nanobiomaterials are described here. DNA has been used to stabilize the enzymes intercalated in the galleries of the inorganic solid, alpha-Zr(iv) phosphate (alpha-Zr(HPO(4))(2).H(2)O, abbreviated as alpha-ZrP). Interestingly, the presence of DNA improved the activity and stability of the bound enzymes. Key studies leading to the current strategy are presented initially, and these are followed by more recent developments. Several enzymes and proteins, including horseradish peroxidase, lysozyme, glucose oxidase, chymotrypsin, bovine serum albumin, cytochrome c, met-hemoglobin and met-myoglobin are successfully intercalated in the galleries of alpha-ZrP, under benign ambient conditions (aqueous buffered solutions, at room temperature and neutral pH). These novel materials are characterized by XRD, SEM and TEM as well as by biochemical, calorimetric and spectroscopic methods. Spectroscopic studies (circular dichroism, CD), for example, indicated that co-intercalation of DNA improved the retention of bound enzyme structure. The activity was enhanced markedly (five-fold) when DNA is co-intercalated, when compared to the activity in the absence of DNA. Addition of DNA to the sample, after enzyme intercalation, did not make any improvements. Our hypothesis is that enzyme-DNA supramolecular complex binds to the solid and the unfavorable interactions between the enzyme and the solid are minimized. These novel nanobiocomposite materials provide a simple method for packaging DNA and aid in engineering more effective synthetic materials for gene/RNA-delivery and drug delivery applications.
 ...
PMID:Novel enzyme/DNA/inorganic nanomaterials: a new generation of biocatalysts. 1804 9

In this report, a four-component nanocomposite, trypsin-immobilized polyaniline-coated Fe(3)O(4)/carbon nanotube composite, was synthesized for highly efficient protein digestion. Fe(3)O(4) was deposited by the chemical coprecipitation of Fe(2+) and Fe(3+) in an alkaline solution containing carbon nanotubes (CNTs) to prepare nano-Fe(3)O(4)/CNT composite. Subsequently, polyaniline (PA) was assembled on the Fe(3)O(4)/CNT composite by the in situ polymerization of aniline in the presence of trypsin to obtain trypsin-immobilized PA/Fe(3)O(4)/CNT nanocomposite. The novel 1D superparamagnetic biomaterial has been characterized by TEM, SEM, XRD, and magnetometric analysis. The feasibility and performance of the unique magnetic biomaterial have been demonstrated by the tryptic digestion of bovine serum albumin, myoglobin, and lysozyme within 5min. The digests were identified by MALDI-TOF MS with sequence coverages that were comparable to those obtained from the conventional in-solution tryptic digestion. The present biocomposite offers considerable promise for protein analysis due to its high magnetic responsivity and excellent dispersibility. It can be easily isolated from the digests with the aid of an external magnetic field. Because the enzyme-immobilized nanocomposite can be prepared by a simple two-step deposition approach at low cost, it may find a wide range of biological applications including proteome research.
 ...
PMID:Immobilization of trypsin in polyaniline-coated nano-Fe3O4/carbon nanotube composite for protein digestion. 1835 64

Since the discovery of ordered mesoporous silica M41S in 1992, a variety of ordered mesoporous materials have been synthesized by using the template technique. In this work, aminosilane-modified SBA-15 nanoparticles were prepared by incorporating various aminosilanes on original SBA-15 via post synthesis method. These aminosilanes were 3-aminopropyltriethoxysilane, N-2(-aminoethyl)-3-aminopropyl trimethoxysilane and (3-trimethoxysilylpropyl)diethylenetriamine. The synthesized nanoparticles were characterized by XRD, SEM, TEM and FT-IR. Adsorption and release studies of bovine serum albumin (BSA), lysozyme and myoglobin on SBA-15 samples were investigated. It was found that the synthesized SBA-15 nanoparicles can be successfully applied in drug delivery system.
 ...
PMID:Adsorption properties of proteins on SBA-15 nanoparticles functionalized with aminosilanes. 1919 10

Rapid assessment of acute myocardial infarction (AMI) was successfully demonstrated using an improved superparamagnetic polymer microsphere-assisted sandwich fluoroimmunoassay to detect two early cardiac markers-myoglobin and human heart-type fatty acid binding protein (H-FABP). This assay used a preparation of superparamagnetic poly(styrene-divinylbenzene-acrylamide) microspheres, glutaraldehyde-coupled capture antibodies (monoclonal anti-myoglobin 7C3 and anti-H-FABP 10E1) grafted onto the polymer microspheres, and a sequential sandwich fluoroimmunoassay using detection antibodies (FITC-labeled anti-myoglobin 4E2 and FITC-labeled anti-H-FABP 9F3). Characterization of the polymer microspheres by TEM, SEM and Fourier transform infrared spectroscopy (FT-IR) showed that the microspheres were uniformly round with an average diameter of 1.12 microm, and had a Fe(3)O(4)-polymer core-shell structure (shell thickness was about 84 nm) with 0.22 mmol/g amino groups on their surfaces. The magnetic behavior of the Fe(3)O(4)-polymer microspheres was superparamagnetic (M(s)=13 emu/g, H(c)=13.1 Oe). Fluorescence images of the post-immunoassay microspheres recorded using a confocal laser-scanning microscope showed that the average fluorescence intensity was correlated with the concentration of cardiac markers, in agreement with the results obtained by an F-4500 FL spectrophotometer; this indicated that the fluoroimmunoassay could be used to semi-quantitatively detect both myoglobin and H-FABP. The detection limit was 25 ng/mL for myoglobin and 1 ng/mL for H-FABP.
 ...
PMID:Superparamagnetic microsphere-assisted fluoroimmunoassay for rapid assessment of acute myocardial infarction. 1939 9

A novel biocompatible composite film based on a water-insoluble surfactant, didodecyldimethylammonium bromide (DDAB), and a hydrophobic room-temperature ionic liquid (RTIL), 1-hexyl-3-methyl-imidazolium hexafluorophosphate (HIMIMPF(6)), for the immobilization of biocatalytical proteins was reported. Differential scanning calorimetry (DSC) showed that the DDAB-HIMIMPF(6) composite film has higher thermal stability than the DDAB film alone. SEM images indicated that different microstructures existed between the DDAB film and the composite film, indicating the interaction between DDAB and RTILs. This composite can be used as the immobilization matrix of proteins and other biomacromolecules. Heme-proteins, including hemoglobin (Hb), myoglobin (Mb) and horseradish peroxidase (HRP), were used as model proteins for studying the electrochemical behaviors of the resulting biocatalytical composite films. In the case of Hb, a pair of well-defined quasi-reversible redox peaks was obtained when the composite film containing Hb was modified on a glassy carbon electrode. The formal potential (E degrees '), the surface coverage (Gamma(*)) and the electron transfer rate constant (k(s)) were calculated as -0.308V, 1.32x10(-11)molcm(-2) and 11.642s(-1), respectively. While, these parameters for Hb on DDAB films alone were -0.309V, 7.20x10(-12)molcm(-2) and 2.748s(-1), respectively. Therefore, the composite are more suitable for the direct electron transfer between Hb than DDAB alone. The native conformation and bioactivity of Hb adsorbed on the composite film was proved to be maintained, reflected by the unchanged ultraviolet-visible (UV-vis) as well as the catalytic activity toward hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) compared with the free Hb molecules. Furthermore, Hb on the composite film are more sensitive for the detection of hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) than that on DDAB film alone. The linear range of H(2)O(2) on Hb/DDAB-RTILs/GC electrode is from 0.5 to 57.5microM with linear regression equations I(microA)=0.149+0.00904C(microM), while, the linear range of H(2)O(2) on Hb/DDAB/GC electrode is from 0.5 to 57.5microM with linear regression equations I(microA)=0.0938+0.00553C(microM). For NO, its linear range on Hb/DDAB-RTILs/GC electrode is from 1.8 to 21.6microM with linear regression equations I(microA)=0.0937+0.0232C(microM). But its linear range on Hb/DDAB/GC electrode is from 1.8 to 21.6microM with linear regression equations I(microA)=0.0285+0.0167C(microM). Similar results were observed for Mb and HRP in the DDAB-HIMIMPF(6) composite film.
 ...
PMID:Electrochemical behavior of biocatalytical composite based on heme-proteins, didodecyldimethylammonium bromide and room-temperature ionic liquid. 2017 91


<< Previous 1 2 3 Next >>