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Query: UMLS:C0149871 (
deep vein thrombosis
)
12,364
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We have previously demonstrated an in vivo model of
deep vein thrombosis
which suggests that the neutrophil promotes vascular injury and thrombosis following blood flow stasis. Since leukotrienes are potent mediators of vascular injury and neutrophil (PMN) chemotaxis, we wished to determine if in vivo inhibition of 5-lipoxygenase would reduce neutrophil mediated events in our model. Lipoxygenase was inhibited in vivo with 2,3-diethyl-4-methoxy,1-naphthalenol acetate (U-66,855). The in vivo activity of U-66,855 was demonstrated in 4 cats. Each animal was treated with 5 mg/kg of U-66,855 intravenously. Blood cell leukotriene B4 (LTB4) and thromboxane A2, via its metabolite thromboxane B2 (TBX2) was assessed before and 30, 60, and 120 min after dosing. Blood cell LTB4 and TBX2 production was stimulated by A23187 (24 microM) and assayed by radioimmunoassay. We exposed and isolated a 3-cm segment of the jugular veins from 10 additional cats 5 of which were treated with U-66,855 (5 mg/kg, iv). In order to assess the effect of stasis, the jugular veins were ligated at the thoracic inlet for 2 hr after which the veins were perfused, fixed in 2.5% glutaraldehyde, and prepared for electron microscopy. U-66,855 reduced LTB4 production significantly (P less than 0.01), but not TBX2. In untreated cats, PMNs adhered to and migrated underneath the venous endothelium. Additionally, platelets, fibrin and formed thrombi were found on the basement membrane exposed by the migrating neutrophils. In contrast, we observed significantly reduced PMN adhesion as well as no fibrin deposition in veins obtained from cats treated with U-66,855. The results suggest that 5-lipoxygenase inhibition can significantly reduce undesirable neutrophil/vessel wall interactions.
Exp
Mol
Pathol 1986 Dec
PMID:Leukocyte mediated vein injury and thrombosis is reduced by a lipoxygenase inhibitor. 302 12
Hypervascularity, focal necrosis, persistent cerebral edema, and rapid cellular proliferation are key histopathologic features of glioblastoma multiforme (GBM), the most common and malignant of human brain tumors. By immunoperoxidase and immunofluorescence, we definitively have demonstrated the presence of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFr) in five out of five human glioma cell lines (U-251MG, U-105MG, D-65MG, D-54MG, and CH-235MG) and in eight human GBM tumor surgical specimens. In vitro experiments with glioma cell lines revealed a consistent and reliable relation between EGFr activation and VEGF production; namely, EGF (1-20 ng/ml) stimulation of glioma cells resulted in a 25-125% increase in secretion of bioactive VEGF. Conditioned media (CM) prepared from EGF-stimulated glioma cell lines produced significant increases in cytosolic free intracellular concentrations of Ca2+ ([Ca2+]i) in human umbilical vein endothelial cells (HUVECs). Neither EGF alone or CM from glioma cultures prepared in the absence of EGF induced [Ca2+]i increases in HUVECs. Preincubation of glioma CM with A4.6.1, a monoclonal antibody to VEGF, completely abolished VEGF-mediated [Ca2+]i transients in HUVECs. Likewise, induction by glioma-derived CM of von Willebrand factor release from HUVECs was completely blocked by A4.6.1 pretreatment. These observations provide a key link in understanding the basic cellular pathophysiology of GBM tumor angiogenesis, increased vascular permeability, and cellular proliferation. Specifically, EGF activation of EGFr expressed on glioma cells leads to enhanced secretion of VEGF by glioma cells. VEGF released by glioma cells in situ most likely accounts for pathognomonic histopathologic and clinical features of GBM tumors in patients, including striking tumor angiogenesis, increased cerebral edema and hypercoagulability manifesting as focal tumor necrosis,
deep vein thrombosis
, or pulmonary embolism.
Mol
Biol Cell 1993 Jan
PMID:Epidermal growth factor stimulates vascular endothelial growth factor production by human malignant glioma cells: a model of glioblastoma multiforme pathophysiology. 768 Feb 47
A heterozygous GTG to ATG (Val297Met) mutation was detected in a patient with inherited protein C deficiency and
deep vein thrombosis
. Cosegregation of the mutation with protein C deficiency was observed through a family pedigree study. Molecular models of the serine protease domains of wild type and mutant protein C were constructed by standard comparative method. Val 297 was found to be located in the hydrophobic core of the protein. Although the substitution of Met for Val does not greatly alter the hydrophobicity of the protein, it introduces a bulkier side chain, which yields steric hindrance between this residue and adjacent residues, such as Met364, Tyr393, Ile321, Ile323, and Val378. It seems that the Met can not fit into the tight packing into which it is trapped, thereby probably inducing misfolding and/or greater instability of the protein. Such misfolding and/or instability thereby eventually disturbs the catalytic triad, in consistent with the observed type I deficiency state.
Exp
Mol
Med 1999 Mar 31
PMID:A molecular model of a point mutation (Val297Met) in the serine protease domain of protein C. 1023 Oct 23
A fluorogenic probe-based PCR assay (Taqman; Perkin Elmer corp/Applied Biosystems, Foster City, CA, USA) was used for the detection of Factor V Leiden, a point mutation in the factor V gene (G1691A) that is the most common inherited risk factor for
Deep Vein Thrombosis
. This assay allows for the direct detection of specific PCR products within minutes of completion of the PCR by monitoring the increase in fluorescence of a dye-labelled oligonucleotide probe. Two dye-labelled probes are used in this allelic discrimination assay, one probe for each allele in the two-allele system. Each probe consists of an oligonucleotide with a 5'-reporter dye and a 3'-quencher dye. Tet (6-carboxy-4,7,2',7'-tetrachloro-fluorescein) is covalently linked to the 5'-end of the probe for the detection of allele 2 (wild-type). Fam (6-carboxy-fluorescein) is covalently linked to the 5'-end of the probe for detection of allele 1 (mutant). Each of the reporters is quenched by Tamra (6-carboxy-N,N,N', N'-tetramethylrhodamine) attached via a linker arm located at the 3'-end of each probe. The two probes were complementary to a 24-base sequence at the factor V Leiden mutation site, but differing in the 5'-labelled reporter dye and the nucleotide opposite the mutation site (C vs T). Wild-type and factor V Leiden alleles were differentiated in highly purified DNA and crudely purified DNA specimens. The assay was successfully applied to genomic DNA from leukocytes isolated from whole blood. The factor V status of 120 patients as determined by this method was in complete concordance with a standard PCR-based assay and clearly discriminated between healthy wild-type (+/+), factor V Leiden homozygote (-/-) and heterozygote (+/-) carriers.
Mol
Cell Probes 2000 Aug
PMID:Factor V Leiden genotyping using real-time fluorescent polymerase chain reaction. 1097 Jul 29
Thrombophilia traditionally refers to rare inherited defects leading to enhanced coagulation, especially of the venous system. In recent years, a broader search for genetic polymorphisms of prothrombotic genes has been carried out to determine the relative impact on venous and arterial thrombosis. The bulk of evidence is drawn from numerous, often small, heterogeneous, case control association studies, with a variety of end points (
deep venous thrombosis
, myocardial infarction, or stroke). The data are often conflicting and inconclusive with only factor V Leiden and prothrombin polymorphisms having clear associations with venous thrombosis. Many of the polymorphisms interact with established cardiovascular risk factors, in particular smoking, to increase greatly the risk of a thrombotic episode. Future studies will need to consider the confounding factors of sample size, race, and clinical end points as well gene-environment interactions.
Mol
Pathol 2000 Dec
PMID:Thrombophilia, polymorphisms, and vascular disease. 1119 48
Protein C (PC) is the pivotal anticoagulant and antithrombotic in the human coagulation cascade. PC deficiency can result in major medical problems such as
deep vein thrombosis
(
DVT
), leading to tissue oxygen deprivation. PC treatment has no bleeding or skin necrosis problems because it circulates in the blood as a zymogen and is only activated when and where it is needed. One source of PC is transgenic animal milk. The major components in the milk, such as alpha-casein, beta-casein, kappa-casein, alpha-lactalbumin and beta-lactoglobulin, are proteins that must be separated from PC. Immobilized metal affinity chromatography (IMAC) is an inexpensive separation technology with relatively high specificity, and it has great potential for difficult protein separations. After systematic studies of different chelator, metal ion and buffers, the combination of iminodiacetic acid (IDA) and Fe was found to be effective to separate PC from major milk components. alpha-Lactalbumin and beta-lactoglobulin fell through the column in the starting buffer. PC was eluted. alpha-Casein, beta-casein, kappa-casein remained bound in the column after PC elution. This technology might be applied for PC separation from transgenic animal milk. It is very important for PC production in large quantities and at low cost to treat PC-deficient patients.
Comp Biochem Physiol A
Mol
Integr Physiol 2002 May
PMID:Chelator, metal ion and buffer studies for protein C separation. 1206 12
The G20210A mutation variant of prothrombin gene is the second most frequent mutation identified in patients with
deep venous thrombosis
, after factor V Leiden. The risk for developing
deep venous thrombosis
is high in patients identified as heterozygous for G20210A mutation. In order to identify this polymorphism in the gene coding prothrombin, the 345bp fragment in the 3'- untranslated region of the prothrombin gene was amplified using amplification by polymerase chain reaction and enzymatic digestion by HindIII (restriction endonuclease enzyme). The products of amplification and enzymatic's digestion were analized using agarose gel electrophoresis. We investigated 20 patients with venous leg ulcers and we found 2 heterozygous (10%) for G20210A mutation. None of the patients in the control group had G20210A mutation. Our study confirms the presence of G20210A mutation in the Romanian population. Our study also shows the link between venous leg ulcers and this polymorphism in the prothrombin gene.
J Cell
Mol
Med
PMID:G20210A prothrombin gene mutation identified in patients with venous leg ulcers. 1206 73
Tissue factor pathway inhibitor (TFPI) is a multivalent Kunitz-type serine proteinase inhibitor that plays a central role in the extrinsic pathway of blood coagulation. In earlier studies we could identify the [P151L]TFPI mutant, and we could also demonstrate that heterozygous carriers of this mutant show a nine-fold increased risk for
deep venous thrombosis
(
DVT
). To express greater amounts of both proteins and to enable their characterization, we expressed wild-type TFPI as well as [P151L]TFPI in High Five insect cells with expression rates of up to 215 ng/ml for wild-type TFPI and 214 ng/ml for [P151L]TFPI. The specific inhibitory activities for the recombinant proteins were determined as 11.3 and 11.5 mU/ng, respectively. Both proteins were detected via Western blot analysis and ELISA. The recombinant proteins' inhibitory activities were characterized by a chromogenic assay and by the determination of a modified activated thromboplastin time (aPTT) in which both of them proved to be inhibitorily active. We also examined both recombinant proteins' binding properties to glycoproteins, glycosaminoglycans, lipoproteins and tissue factor. Our results show that we have developed an efficient model system for the recombinant expression of inhibitorily active wild-type TFPI as well as [P151L]TFPI in insect cells, and we were able to characterize both proteins' inhibitory properties by determination of their influence on the aPTT and also their binding properties. Although both recombinant proteins did not show a significant difference in their effect on the aPTT, their binding properties differed significantly between the wild type and mutant protein.
Mol
Cell Biochem 2006 Feb
PMID:Expression and characterization of wild-type TFPI and the [P151L]TFPI mutant in insect cells. 1644 83
Aim-To determine the relation of the low anticoagulant response phenotype with the Factor V Q506 (Leiden) mutation in a cohort of patients with thrombophilia.Methods-Fifty four patients with either a personal or family history of
deep vein thrombosis
were investigated both for their anticoagulant response by the activated protein C resistance test (APCR) and their genetic status in respect of the Leiden mutation by means of a PCR-RFLP method.Results-Low APCR ratios do not necessarily predict possession of the Leiden mutation. Conversely, normal ratios do not exclude the mutation. Of 14 individuals with low APCR ratios, the Leiden mutation was absent in five. Of the remainder, three were heterozygous and six homozygous. Of nine heterozygote individuals, only three had low APCR ratios. All patients homozygous for the defect had low APCR ratios.Conclusions-These results lend further weight to the hypothesis that the APC resistant phenotype results from more than one genetic defect and indicate the value of combined functional and molecular investigations in all patients with thrombophilia.
Clin
Mol
Pathol 1996 Aug
PMID:An assessment of the comparative utility of functional and molecular level analyses in the investigation of patients with thrombophilia. 1669 79
NAPc2, an anticoagulant protein from the hematophagous nematode Ancylostoma caninum evaluated in phase-II/IIa clinical trials, inhibits the extrinsic blood coagulation pathway by a two step mechanism, initially interacting with the hitherto uncharacterized factor Xa exosite involved in macromolecular recognition and subsequently inhibiting factor VIIa (K(i)=8.4 pM) of the factor VIIa/tissue factor complex. NAPc2 is highly flexible, becoming partially ordered and undergoing significant structural changes in the C terminus upon binding to the factor Xa exosite. In the crystal structure of the ternary factor Xa/NAPc2/selectide complex, the binding interface consists of an intermolecular antiparallel beta-sheet formed by the segment of the polypeptide chain consisting of residues 74-80 of NAPc2 with the residues 86-93 of factor Xa that is additional maintained by contacts between the short helical segment (residues 67-73) and a turn (residues 26-29) of NAPc2 with the short C-terminal helix of factor Xa (residues 233-243). This exosite is physiologically highly relevant for the recognition and inhibition of factor X/Xa by macromolecular substrates and provides a structural motif for the development of a new class of inhibitors for the treatment of
deep vein thrombosis
and angioplasty.
J
Mol
Biol 2007 Feb 16
PMID:Intermolecular interactions and characterization of the novel factor Xa exosite involved in macromolecular recognition and inhibition: crystal structure of human Gla-domainless factor Xa complexed with the anticoagulant protein NAPc2 from the hematophagous nematode Ancylostoma caninum. 1717 31
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