Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00631 (Gel)
 14,881 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gel filtration of human platelet-rich plasma (PRP) on columns of Sepharose 2B removed at least 99.85% of the plasma proteins from platelets when a column 10 cm in height was used and a plasma volume 11 to 14% of the gel-bed volume was applied. ADP and ATP levels in gel-filtered platelets (GFP) were not significantly different from those in PRP. By transmission electron microscopy, GFP were indistinguishable from PRP. Gel filtration appears to be a highly satisfactory technique of separating platelets from plasma without modifying structure, function, or contents significantly. The roles of several crude protein fractions in platelet aggregation and aspirin's inhibition of aggregation were examined. Fraction I (mostly fibrinogen) enhanced collagen-induced aggregation of gel-filtered platelets; Fraction V (mostly albumin) was inhibitory. Fraction II (mostly gamma-globulin) or gelatin had no significant effect. Aspirin added to gel-filtered platelets inhibited aggregation by 80%. The addition of mixtures of plasma proteins containing albumin increased albumin's inhibitory effect. Incubation of gel-filtered platelets with aspirin labeled in the carboxyl position resulted in no uptake of the label. In contrast, incubation with acetyl-labeled aspirin was followed by uptake of more than 2 X 10(6) acetyl groups per platelet in 1 minute. Incubation for 30 minutes resulted in a five- to sixfold further increase in uptake of the label. Aspirin can acetylate platelets and inhibit aggregation directly. Plasma proteins, in particular albumin or a contaminant of the albumin fraction tested, enhance the inhibitory effect of aspirin on platelet aggregation.
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PMID:Gel-filtered human platelets. Ultrastructure, function, and role of proteins in inhibition of aggregation by aspirin. 5 50

Migration of alveolar macrophages collected by lavage from normal rhesus monkeys was tested in an under agarose migration system. Lung lining material and serum albumin obtained from normal rhesus monkeys enhanced the random migration of alveolar macrophages. A chemotactic effect for alveolar macrophages was demonstrated in response to lung lining material. Gel filtration of lung lining material using Sephadex G-200 indicated the presence of 4 distinct fractions. Fraction IV, which had a molecular weight of less than 5,000 daltons, had the greatest ability to enhance alveolar macrophage migration. Macrophages obtained from lungs of rhesus monkeys after they breathed an oxidant gas (ozone) for 7 days demonstrated decreases in both the number of cells randomly migrating and the distance they migrated. The addition of normal lung lining material to macrophages exposed to ozone enhanced their random mobility but did not restore migration values to control values. Ozonized lung lining material or rhesus monkey serum did not significantly alter alveolar macrophage migration from that of control lung lining material or serum. These data indicate that components of the acellular lining material of the lung can produce directional migration of alveolar macrophages and may serve to direct the central flow and clearance of macrophages from alveolar regions. Intraluminal alveolar macrophage accumulation during lung insult with ozone appeared to be related more to migration inhibition of resident cells than to recruitment of additional cells by chemotaxis.
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PMID:Alveolar macrophage migration. Influence of lung lining material and acute lung insult. 11 95

A fibrillar protein complex, possessing ouabain-insensitive Ca2+-ATPase activity was isolated from human erythrocyte membranes by using a low ionic strength extraction procedure. Mg2+-ATPase activity was revealed upon addition of rabbit skeletal muscle actin, thus demonstrating the presence of a myosin-like protein in the crude extract of the erythrocyte membrane. Upon sodium dodecylsulfate gel electrophoresis, the extract showed mainly the doublet of subunit molecular weight bands of 230 000 and 210 000, and more than 10 faster moving bands. Gel filtration of the erythrocyte membrane extract on Sepharose 4B furnished 4 fractions. Fraction I, containing the doublet and 80 000, 60 000 and 46 000 subunit molecular weight bands was 5-fold purified with respect to Ca2+-ATPase activity, but was devoid of actin-activated Mg2+-ATPase activity. Fraction II, containing only the doublet, was devoid of Ca2+ and actin-activated Mg2+-ATPase activity. The 210 000 subunit molecular weight protein could be phosphorylated in the presence of Mg2+ in the crude extract and Fraction I but not in Fraction II.
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PMID:Actin-activated ATPase from human erythrocytes. 12 97

Two proteins with gonadotropin activity have been isolated from a highly purified chum salmon (Oncorhynchus keta) gonadotropin preparation (G-75 Fraction II) by chromatography on DEAE Bio Gel A. These gonadotropins exhibited distinct behaviour in polyacrylamide gel electrophoresis, chromatography on Sephadex G-75 superfine, and ratios of cAMP stimulation in immature rainbow trout ovaries and testes. Rechromatography of G-75 Fraction II on Sephadex G-75 superfine gave a symmetrical protein peak with a coincident cAMP activity profile. Repeated freezing and thawing elicited a shift in the cAMP activity profile toward the trailing edge of the protein peak. Data are discussed in terms of two gonadotropin molecules which respond differently to phase changes. Charge polymorphism was exhibited by isoelectric focusing in polyacrylamide gels of one of the DEAE fractions. Five UV absorbing bands were observed which stimulated cAMP production in immature rainbow trout gonads. Three of these bands increased adenyl cyclase activity in trout ovaries and testes. One of the bands stimulated cAMP production primarily in trout testes and the other stimulated trout ovaries, providing evidence for two gonadotropins, each of which is sex specific.
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PMID:Fish gonadotropin(s). III. Evidence for more than one gonadotropin in chum salmon pituitary glands. 17 57

Partial purification of cyclic AMP-binding proteins from porcine thyroid cytosol was performed by gel filtration on Bio Gel 1.5 m followed by ion exchange chromatography on DEAE Sephadex A25. Three fractions presenting cyclic AMP-binding activities were resolved by gel filtration (I, II, III). Approximate molecular weights were respectively 280 000, 145 000 and 65 000. Fraction I was further resolved into two peaks (Ialpha and Ibeta) on DEAE-Sephadex A25. Fractions I, Ialpha, Ibeta comigrated with protein kinase activity whereas peaks II and III did not. These fractions differed with respect to the folling characteristics: rate and stability of cyclic AMP binding to isolated fractions were differently affected by pH (4.0 or 7.5). Electrophoretic mobility on polyacrylamide gels (5%) of fractions preincubated with cyclic [3H]AMP showed similar mobilities for Ialpha, Ibeta or II (Rf 0.37) whereas fraction III displayed a much greater mobility (RF 0.73); Scatchard plots were linear for fractions Ialpha, II and III with an apparent Kd in the same range (2 to 5 nM) whereas fraction Ibeta generated a biphasic plot with Kd 0.4 nM and 20 nM; cyclic [3H] AMP added to fraction I, Ialpha or Ibeta generated a cyclic [3H] AMP-binding protein complex of lower molecular weight as shown by Sephadex G 150 filtration; on the basis of the elution volume, this complex was not distinguished from fraction II. In the course of this work, we separated at the first step of purification (Bio Gel 1.5 m) a protein kinase not associated with cyclic AMP binding activity which exhibited marked specificity for protamine as compared to histone II A.
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PMID:Cyclic AMP-binding proteins and protamine kinases in porcine thyroid cytosol. 21 21

This communication presents evidence for the existence in the ovine testis of proteinaceous factors which suppress LH as well as FSH. Isolation of these factors has been achieved by using three different procedures: cytosol preparation, metaphosphoric acid extraction and ultrafiltration. Chromatography of cytosol or metaphosphoric acid extract on Sephadex G-75 resulted in separation into three protein fractions designated as G-75-I, II and III in order of their elution. When administered to castrated male rats, Fraction G-75-I suppressed circulatory levels of LH (53% inhibition, P less than 0.05) without altering FSH. The most retarded fraction, G-75-III, suppressed FSH (29% inhibition, P less than 0.001) without any concomitant change in LH. When fraction G-75-III was further fractionated on Sephadex G-25, three components were found and two, G-25-II and G-25-III, were biologically active. These fractions were homogeneous on polyacrylamide disc-gel electrophoresis. The FSH-suppressing factor (inhibin) was heat labile and susceptible to trypsin digestion, indicating that it is proteinaceous. Treatment with urea did not reveal any subunits. The molecular weight of this factor, as determined by gel filtration and SDS-urea gel electrophoresis was estimated to be around 1400-1500. The absence of sialic acid and the molecular weight data suggested that the isolated material was a simple protein and probably a small peptide. Gel filtration on Sephadex G-75 of the metaphosphoric acid extracts of liver, kidney, testis and ovary revealed an identical elution pattern for ovarian and testicular inhibin.
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PMID:Characterization of a gonadal factor involved in the control of FSH secretion. 29 12

In this work we have studied the chromatographic pattern on Bio-Gel P-30 columns of the glucagon-like immunoreactivity (GLI) present in unextracted plasma from normal dogs in the basal state and after intraduodenal administration of glucose. Basal plasma GLI, measured by R-8 antiserum, was distributed in four distinct fractions, whose approximate molecular weights were: greater than 30000 delta (Fraction I), 10000 delta (Fraction II), 3500 delta (Fraction III) and 2000 delta (Fraction IV). Fraction I accounted for the highest percent of total immunoreactivity. The increase in plasma GLI during glucose absorption was due to a significant increase of Fraction II, which may well correspond to tissue GLI Peak I, while no significant changes were evident in the other three fractions. The fact that tissue Peak I (or plasma Fraction II) ssems to be the factor secreted during glucose absorption puts the material/s of this molecular size in the first place for further investigation.
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PMID:Chromatographic pattern of gut glucagon-like immunoreactivity (GLI) in plasma before and during glucose absorption. 47 29

Purification of rat liver tyrosine tRNA synthetase yields two protein fractions A and B and both fractions are required for charging of tyrosine to tRNAtyr. Fraction B catalyzes the activation of tyrosine. Fractions A and B have been purified to near homogeneity and they are composed of single polypeptide chains of 62,000 daltons each. Gel filtration studies suggest a molecular weight of 120,000 for the synthetase.
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PMID:Purification and properties of tyrosyl tRNA synthetase of rat liver. 59 93

Bacteriophage MX-1 is a virulent DNA phage for Myxococcus. The host range includes strains of Myxococcus xanthus, M. fulvus and M. virescens. The phage has a sedimentation coefficient (S degrees 20,w) of 1145S and a density of 1-531 g/ml. By using SDS-polyacrylamide gel electrophoresis, 23 phage proteins with apparent mol. wt. between 10000 and 150000 were resolved. Gel filtration in the presence of non-ionic detergent partially resolved the proteins. The fraction excluded from Sephadex G-100, fraction 1, contains two glycoproteins. Fraction 1 was resolved into three fractions (1-1, 1-2 and 1-3) by chromatography on Sephadex G-200. The glycoproteins were present in fraction 1-2; all the proteins from this fraction were derived from the phage tail. Comparison of the amino-acid, hexosamine and neutral-sugar compositions of the two glycoproteins showed that they are distinct molecular species; the smaller molecule is not a subunit of the larger. The significance of these findings is discussed and compared with the proteins of the tails of T-even phage of Escherichia coli.
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PMID:Bacteriophage MX-1: properties of the phage and its structural proteins. 81 57

Raw extract in 2 m CaCl2 of bovine nasal septum cartilage was eluted from 4 per cent agarose gel to give a "void volume" Fraction v-4, which was indistinguishable in composition and behavior on viscometric and sedimentation analysis from the densest fraction obtained by associative centrifugation in a cesium chloride density gradient. The sulfated proteoglycan was precipitated (Fraction A) by cetylpyridinium chloride from acidic solutions of Fraction v-4 or of dialyzed raw ectract. Neutralization under conditions of low ionic strength precipitated a further small fraction (B), which contained from 0.5 to 1 per cent of the uronic acid in the original extract. Analysis by associative and dissociative density gradient centrifugation demonstrated that Fraction B resembled in effective density known samples of hyaluronic acid from other sources. Gel chromatography of proteolytic digests of Fractions A and B on 6 per cent agarose indicated that cetylpyridinium chloride precipitation essentially separated sulfated proteoglycan (A) from hyaluronic acid (B). A viscosity-average molecular weight of about 5 x 10(5) was estimated for a sample of Fraction B purified in a dissociative (4 M guanidine hydrochloride + CsCl) density gradient. Sedimentation velocity data were consistent with this result. Analysis of hexosamines showed that the sample contained 96 per cent glucosamine, confirming the identification of hyaluronic acid. The proteoglycan fraction (A) resembled "subunits" in its sedimentation behavior.
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PMID:Isolation and physical characterization of hyaluronic acid prepared from bovine nasal septum by cetylpyridinium chloride precipitation. 83 35


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