PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “FACTOR VII”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18Linked to original sources
PubMed1988

Age-related changes in factor VII activation in healthy women.

1. To investigate the age-related changes in factor VII activation in healthy women, a regular factor VII clotting assay (factor VIIc) was carried out simultaneously with a new enzyme immunoassay for the quantification of antigen factor VII (factor VIIag). 2. Both factor VIIc and factor VIIag levels were positively correlated with age (r = 0.79 and r = 0.62, respectively, n = 25, P less than 0.001). The rise with age in factor VIIc was steeper than in factor VIIag and the ratio of factor VIIc to factor VIIag (an indicator of the activity state of factor VII) increased with age (r = 0.42, P less than 0.05). 3. The results show that an increased conversion of native single-chain factor VII to the fully active double-chain form is associated with advancing age in women. 4. This finding is consistent with a possible role of activated factor VII in the pathogenesis of thrombo-occlusive vascular disease in women.

Adult↗
PubMed2002

Genetic contribution to factor VII levels in families of patients undergoing coronary arteriography.

An elevated plasma level of factor VII is a risk factor for coronary artery disease. We investigated environmental, familial, and genetic influences on factor VII activity in 508 family members of 87 probands who underwent elective coronary arteriography. Maximum likelihood methods were used to fit several genetic and non-genetic models of inheritance to these data to determine whether an unobserved Mendelian major gene could explain the familial distribution of factor VII. Factor VII activities were adjusted for age, gender, body mass index, smoking, alcohol consumption, menopause status, and triglycerides prior to this segregation analysis (this model accounted for 33.5% of the total variation). Adjusted factor VII activities showed strong familial aggregation with an estimated parent-offspring correlation of 0.34, sibling correlation of 0.36 and a smaller spouse correlation of 0.16. Regressive models were used to test genetic and non-genetic models in these 87 families. Mendelian single-locus models with either two or three underlying genotypic distributions of factor VII activities were best supported by these data. Essentially, these Mendelian models suggest most individuals come from a low distribution (mean, 116%), with a few individuals homozygous for a high allele drawn from a distribution with a mean of 166%. Future linkage studies may be worthwhile to further clarify the mechanisms controlling factor VII activity.

Adolescent↗
PubMed1995

[Recombinant activated Factor VII (Novoseven Novo Nordisk) for hemostasis in acquired Factor VIII-inhibitor hemophilia].

One life threatening mediastinal hemorrhage and two limb threatening hemorrhages, one in the retroperitoneal and thigh muscles and the other in the back of the hand requiring surgical evacuation, were treated with recombinant activated factor VII concentrate (rFVIIa; Novoseven Novó Nordisk) in a patient with a postpartum acquired inhibitor against factor VIII. High dose activated prothrombin complex concentrate (Feiba sTIM4 Immuno), repeatedly administered, had proven to be ineffective; porcine factor VIII concentrate (Hyate C Porton) had become ineffective due to a rise in inhibitor titers against human and porcine factor VIII as well. 90 micrograms rFVIIa per kg body weight was administered as an i.v. bolus injection every 2-3.5 hours. The treatment periods were 22.5 days in the mediastinal and 11 days in each of the two other hemorrhages. Hemostasis was promptly achieved and maintained. All manipulations (bone marrow biopsy, surgical evacuation of the hematoma, change of venous access, withdrawal of drains, change of dressings) were done immediately after rFVIIa administration, without bleeding complications. There were no side effects despite the high dose, frequent and long lasting treatment with a total of 234 x 4.8 and 46 x 3.6 mg rFVIIa. The concentrate was well tolerated, there were no signs of systemic activation of coagulation, either in the coagulation test results or clinically, in spite of patient's factor VII levels up to 60 U/mL and prothrombin times around 6 s. No inhibitors against patient's factor VII, induced by rFVIIa, were detected. Due to its extrinsic factor VIII bypass effect, rFVIIa led to excellent hemostasis even with inhibitor titers of 376 Bethesda units against human and 44 against porcine factor VIII. Nevertheless, immunosuppressive treatment with cyclophosphamide and prednisone was performed, with prompt decrease of the inhibitor titer.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Frequency of genetic polymorphism (Arg353-->Gln) and factor VII levels in Japanese healthy adults].

We studied factor VII levels and frequency for a G-to-A substitution resulting in the replacement of glutamine for arginine at codon 353 of factor VII by Msp I polymorphism in 101 Japanese healthy adults. An homozygote and seven heterozygotes for the factor VII Gln 353 allele was found in the samples. The frequency of Japanese was not different from those of populations of the United Kingdom, Europe and Afro-Caribbeans, but was different from that in Gurjarati Indians (0.25) previously reported by Humphries et al (Arch Pathol Lab Med 116:1322-1329, 1992). The homozygote had the lowest levels (factor VII activity; 50% and factor VII antigen; 45%) in all samples. The seven heterozygotes had levels of factor VII activity and factor VII antigen about 25% lower than those with only the arginine allele. There were no difference in the levels of factor VII between smoking and no smoking heterozygotes, and between those taking fatty and non-fatty diet.

Adult↗
PubMed1999

Genetic effects for plasma factor VII levels independent of and in common with triglycerides.

BACKGROUND: Coagulation factor VII has been demonstrated as a potential risk factor for cardiovascular disease. Both genes and non-genetic factors are related to plasma levels of factor VII. However, the extent to which genetic effects influence variability in plasma factor VII levels is unknown. Further, increased levels of plasma factor VII are associated with serum triglycerides, yet the reason for this association is not fully understood. METHODS AND RESULTS: Quantitative genetic analyses were applied to evaluate the relative importance of genetic and different environmental influences on plasma factor VII levels and to test the significance of genetic and environmental factors in common to factor VII and triglycerides in 215 pairs of middle-aged and elderly twins, of whom 104 were reared apart and 120 were women. Genetic influences were found to account for 57% of the individual differences in plasma factor VII levels, whereas shared-rearing and residual-familial environmental factors were not significant. Furthermore, a significant genetic correlation of 0.38 was found between factor VII and triglycerides, but the environmental correlation between these two measures was not significant. Genetic factors in common to factor VII and triglycerides explain about 7% of the total variance for factor VII. CONCLUSION: The present study suggests that there are substantial genetic influences on plasma factor VII levels. Furthermore, genetic effects explain the phenotypic association between factor VII and triglycerides.

Aged↗
PubMed1995

Orphan nuclear receptor HNF-4 binds to the human coagulation factor VII promoter.

The human coagulation protease factor VII plays a pivotal role in the initiation of the coagulation cascade by both the extrinsic and the intrinsic pathway. Although the gene, encoding factor VII, is expressed predominantly in the liver, the mechanisms underlying this tissue-specific expression have not been elucidated. In this study, we have analyzed the contribution of 5 kilobases upstream of the ATG translational initiation codon upon hepatic factor VII gene transcription. Transient transfection assays of a set of nested deletions in both liver and non-liver cell lines, HepG2 and HeLa respectively, indicate that several regions are involved in liver-specific expression. A slight negative effect on factor VII promoter activity in HepG2 cells is mediated by sequences upstream of position -1212. DNase I protection experiments reveal six footprints, FPVII1 through FPVII6, within the proximal 714 base pairs but a minimal promoter of 165 base pairs containing only FPVII3-6 is sufficient to confer liver-specific expression in HepG2 cells. Interestingly, FPVII6, at position -14 to +10 on the sense strand, would indicate that an as yet unknown transcription factor covers the ATG translational initiation codon. Gel retardation experiments show that the liver-enriched transcription factor HNF-4 binds specifically to footprint FPVII4 at position -71 to -49. Furthermore, a T --> A transversion, that in the HNF-4 binding site of factor IX causes a severe bleeding disorder, was introduced into the HNF-4-binding site of factor VII and reduced promoter activity by 20-50%. Coordinate HNF-4-mediated regulation of several blood protease genes as well as genes involved in lipid metabolism might account for the positive correlation of these factors with increased risk of occlusive heart diseases.

Amino Acid Sequence↗
PubMed2006

Management of bleeding emergencies: when to use recombinant activated factor VII.

Recombinant activated Factor VII (rVIIa) was originally released as a clotting factor, with use limited to a select group of patients who had few other treatment options. Due to the apparent ability of rVIIa to stop bleeding, no matter what the underlying cause, there is great interest in use of rVIIa in a wide range of bleeding patients. This article discusses rVIIa and its uses in a variety of patients, especially liver disease and trauma patients, and makes suggestions for appropriate use. Although most of the reports on rVIIa are anecdotes and case series, there is increasing data for clinical trials to help guide usage.

Disease Management↗
PubMed2001

Demonstration of the extrinsic coagulation pathway in teleostei: identification of zebrafish coagulation factor VII.

It is not known whether the mammalian mechanism of coagulation initiation is conserved in fish. Identification of factor VII is critical in providing evidence for such a mechanism. A cDNA was cloned from a zebrafish (teleost) library that predicted a protein with sequence similarity to human factor VII. Factor VII was shown to be present in zebrafish blood and liver by Western blot analysis and immunohistochemistry. Immunodepletion of factor VII from zebrafish plasma selectively inhibited thromboplastin-triggered thrombin generation. Heterologous expression of zebrafish factor VII demonstrated a secreted protein (50 kDa) that reconstituted thromboplastin-triggered thrombin generation in immunodepleted zebrafish plasma. These results suggest conservation of the extrinsic coagulation pathway between zebrafish and humans and add credence to the zebrafish as a model for mammalian hemostasis. The structure of zebrafish factor VIIa predicted by homology modeling was consistent with the overall three-dimensional structure of human factor VIIa. However, amino acid disparities were found in the epidermal growth factor-2/serine protease regions that are present in the human tissue factor-factor VIIa contact surface, suggesting a structural basis for the species specificity of this interaction. In addition, zebrafish factor VII demonstrates that the Gla-EGF-EGF-SP domain structure, which is common to coagulation factors VII, IX, X, and protein C, was present before the radiation of the teleosts from the tetrapods. Identification of zebrafish factor VII significantly narrows the evolutionary window for development of the vertebrate coagulation cascade and provides insight into the structural basis for species specificity in the tissue factor-factor VIIa interaction.

Amino Acid Sequence↗
PubMed2003

Palliative open heart surgery in an infant with factor VII deficiency.

An infant with factor VII deficiency underwent palliative open heart surgery for pulmonary atresia with an intact ventricular septum. No references had been found on the management of this rare coagulation disorder in infantile cardiac surgery. We describe the peri- and postoperative management with a replacement therapy including a recombinant factor VIIa concentrate. We conclude that an appropriate replacement therapy is needed to control bleeding during open heart surgery with factor VII deficiency.

Cardiac Surgical Procedures↗
PubMed1975

[Methodological studies on the immunologic determination of proconvertin (factor VII)].

The influence of the different determinations of factor VII activities on the determination of the concentrations of the immunoreactive factor VII in the neutralizing test according to Good-Night were re-examined. The measurement of activity was performed with Seitz filtered cattle plasma as a complex proof of factor VII and X and with a specific artificial deficiency plasma. The examinations had the following results: In the plasma of healthy grown-up people there is a considerable, apparently physiologic range of dispersion of the immunoreactive concentration of factor VII within its normal activity which can be traced irrespective of the used measurements of activity. In plasma samples with a decreased activity of factor VII the values of measurement of the complex evidence will surpass those of the specific determination. The extent of neutralizing the activity in factor VII is not only dependent on the antibody concentration, but will mostly depend on the antibody-antigen relation. The findings obtained prove that the natural deficiency plasma of factor VII used in the original method of Goodnight can be replaced by an artificial substrate plasma.

Adult↗
PubMed2005

Recombinant activated factor VII (rFVIIa, NovoSeven).

Recombinant activated factor VII (rFVIIa, NovoSeven) enhances haemostasis in individuals, with its predominant action limited to areas of injury, apparently without systemic activation of the coagulation cascade. rFVIIa is currently licensed in most countries worldwide, for its use in the treatment of bleeding episodes in patients with hemophilia and the presence of inhibitors. Recently in the European Union, rFVIIa, has been approved for use in congenital Factor VII deficiency and Glanzmann's thrombasthenia. Furthermore, a large number of case series studies and anecdotal evidences, from patients with different bleeding conditions, have now shown that rFVIIa is actually a very valuable general haemostatic agent. It has been reported to reduce bleeding in patients with liver disease, thrombocytopenia/thrombocytopathia, trauma, spontaneous intracerebral hemorrhage and in the reversal of anticoagulant overdosage or toxicity. A number of trials have been carried out, which have shown that it is a relatively safe and well tolerated drug with a few episodes of unwanted thrombosis.

Blood Coagulation Disorders↗
PubMed1999

[Inherited factor VII deficiency and pregnancy. Apropos of 1 case].

Hereditary factor VII deficiency is a rare autosomal recessive condition. Factor VII's level elevates during pregnancy in normal patients, as well in deficient individuals for some authors. Various treatments (fresh frozen plasma, prothrombin complex or factor VII concentrate) have been used to lessen the peri-partum hemorrhage in those factor VII-deficient pregnant women. We report the case of a pregnant woman presenting a factor VII deficiency (level 4%), without variation of level during her pregnancy. The single infusion of factor VII concentrate, prior to delivery, has elevated factor VII's level at 17% and has likely permitted minimal post-partum bleeding. The peripartum management of factor VII deficiency is discussed.

Adult↗
PubMed2004

Congenital factor VII deficiency: a case report.

Factor VII deficiency is a rare congenital blood disorder. Its clinical features are rather variable and ranges from epistaxis to massive intracranial haemorrhage. Treatment involves replacement therapy, which constitutes use of fresh frozen plasma, prothrombin complex concentrates or recombinant activated factor VII. Although it is a rare entity, one still needs to consider it as a probable diagnosis in a newborn with coagulopathy. We report here a case of Factor VII deficiency in a newborn who presented with subdural haemorrhage at day 4 of life.

Blood Component Transfusion↗
PubMed1989

Acquired factor VII deficiency associated with aplastic anaemia: correction with bone marrow transplantation.

We report a patient with severe aplastic anaemia found to have a prolonged prothrombin time due to acquired factor VII deficiency. No evidence for a factor VII inhibitor or inactivator was demonstrable. Laboratory studies identified deficiency both of factor VII activity and factor VII antigen. The factor VII deficiency persisted from clinical presentation until approximately 50 d after allogeneic marrow transplantation when restoration of factor VII activity and antigen was noted. The patient's serum could be depleted of factor VII activity by in vitro incubation with Protein A bound to Sepharose, suggesting the presence of an IgG or IgG containing complex able to bind factor VII, but not neutralize its procoagulant activity. A dual specificity solid phase immunoassay identified a factor VII binding immunoglobulin which was detectable throughout the course of factor VII deficiency. The concordant appearance of this factor VII reactive immunoglobulin and the factor VII deficiency suggested the pathologic role of this immunoglobulin in the aetiology of the factor VII deficiency. This factor VII binding immunoglobulin may have induced rapid plasma clearance of the factor VII molecule or, alternatively, may have modified factor VII synthesis. The immunosuppressive therapy and subsequent lymphohaematopoietic engraftment following allogeneic marrow transplant was accompanied by complete resolution of the factor VII deficiency.

Adolescent↗
PubMed2000

Dimerization of tissue factor supports solution-phase autoactivation of factor VII without influencing proteolytic activation of factor X.

Tissue factor (TF) is a transmembrane receptor that initiates the thrombogenic cascade by assembly with the serine protease factor VII or VIIa (VII/VIIa) resulting in formation of the bimolecular active complex TF.VIIa. Chemical cross-linking studies identified that a minor population of TF forms dimers on the surface of cells, possibly influencing TF.VIIa proteolytic function as a result of dimerization. We here investigate the effects of dimerization of the extracellular domain of TF on the proteolytic function of the TF. VIIa complex. The leucine zipper dimerization domain of the yeast transcriptional factor GCN4 (LZ) was genetically fused at the C-terminus of the extracellular domain of TF separated by a short linker (TF(L)LZ). TF(L)LZ homodimerized with a K(d) similar to that of the LZ peptide. Tryptophan fluorescence indicated that the two TF moieties were in close proximity and parallel orientation in TF(L)LZ. TF(L)LZ dimers bound two molecules of VIIa, and VIIa binding did not influence the TF dimer equilibrium. Dimerization influenced neither amidolytic nor the factor X activation activities of the TF. VIIa complexes. Notably, dimer TF(L)LZ efficiently promoted the autoactivation of VII to VIIa in solution in contrast to monomeric TF(L)LZ or TF(1)(-)(218). Thus, TF dimerization on cells may serve to "prime" the initiation of the coagulation pathway by generating active TF.VIIa complexes for the subsequent activation of downstream macromolecular substrates.

Amides↗
PubMedDate not supplied

Open heart surgery with factor VII deficiency.

A case with marked factor VII deficiency, undergoing open heart surgery for atrial myxoma, is reported. The syndrome was unknown to the patient and only pre-operative routine coagulation studies showed a low prothrombin activity (22%). Further investigations revealed a severe factor VII deficiency. The operation was carried out under factor VII concentrate administration and no bleeding complication occurred.

Factor VII↗