Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:Q8NEX9 (reductase)
 26,410 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Antibiotics of the beta-lactam class may cause coagulation defects and bleeding. It has been suggested that N-methyltetrazolethiol (NMTT), a common side chain group at the 3'-position of the cephem or 1-oxacephem frame, could be responsible for the hypoprothrombinemic effect of the antibiotics and that it could inhibit the liver vitamin K-epoxide reductase activity. Flomoxef (6315-S) is a new oxacephem antibiotic which differs from latamoxef because it has [1-(2-hydroxethyl)-1H-tetrazol-5-yl] thiomethyl (HTT) as a side chain at the 3'-position of cephem group instead of NMTT and an extensive modification of 7 beta-acylamino side chain. The present study was carried out to study its effects on vitamin K-dependent blood coagulation parameters in human volunteers. Ten adult patients (6 men and 4 women), suffering from chronic bronchitis, entered into the study. Each patient received ten 1 g i.m. injections of flomoxef at 12-hourly intervals. Apparently, the treatment with this oxacephem antibiotic had no significant effect. PT, PTT and fibrinogen remained in the normal range in all patients and factors II+VII+X, protein C, protein S and AT III were not depleted. The trend was similar both in men and women. Based on the results of the present study, we conclude that flomoxef is an antibiotic that does not exhibit an effect on blood coagulation, even in males.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Flomoxef, a new oxacephem antibiotic, does not cause hemostatic defects. 846 13

Mild hyperhomocysteinemia has been identified as a risk factor for arterial disease and for venous thrombosis. Individuals homozygous for the thermolabile variant of the methylene tetrahydrofolate reductase gene (MTHFR) which results from a common mutation Ala677-->Val and is found in 5-15% of the general population, have significantly elevated plasma homocysteine levels and may account for one of the genetic risk factors in vascular disease. We have analyzed the prevalence of MTHFR-T homozygotes in patients with arterial disease or venous thrombosis. We studied 191 patients with arterial disease and 127 individuals with venous thrombosis and compared with 296 unmatched controls. The results showed that there was a high prevalence of homozygotes for the mutated MTHFR-T allele among a group of patients with arterial disease (19%) in the absence of hyperlipoproteinemia, hypertension, and diabetes mellitus when compared to controls (4%), odds ratio of 5.52 (95% C.I., 2.27 to 13.51). The prevalence of homozygotes among patients with venous thrombosis was 11%, odds ratio of 2l93 (95% C.I., 1.23 to 7.01). The risk of venous thrombosis remained high, odds ratio of 2.63, even after we excluded 27 patients with hereditary thrombophilia (e.g. factor V Leiden, dysfibrinogenemia, deficiency of protein C, protein S, antithrombin III, or factor XII) from the 127 overall cases with venous thrombosis. These data support the hypothesis that being a homozygote for the MTHFR-T is a risk factor for the development of arterial disease and also for venous thrombosis.
 ...
PMID:The mutation Ala677-->Val in the methylene tetrahydrofolate reductase gene: a risk factor for arterial disease and venous thrombosis. 918 84

According to a recent hypothesis, venous thrombosis results from the concurrence of several factors. This hypothesis was assessed in patients with portal or hepatic venous thrombosis by simultaneously investigating most of the currently identified prothrombotic disorders, local precipitating factors, and other risk factors such as oral contraceptive use. Patients with a tumorous obstruction and patients with cirrhosis with portal vein thrombosis were excluded. The prothrombotic disorders that were investigated included classical and occult myeloproliferative disorders; antiphospholipid syndrome; protein C; protein S and antithrombin deficiency; factor V Leiden; factor II; and methylene-tetrahydrofolate-reductase gene mutations. We found 1 or several prothrombotic disorders and a local precipitating factor in 26 and 10 of the 36 patients with portal vein thrombosis, respectively; and in 28 and none of the 32 patients with hepatic vein thrombosis, respectively. We found a combination of prothrombotic disorders in 5 and 9 patients with portal and hepatic vein thrombosis, respectively, whereas such a combination is expected in less than 1% of asymptomatic subjects. Of the 10 patients with a local precipitating factor, 8 had a prothrombotic disorder. Of the 13 patients who use oral contraceptives, 10 had a prothrombotic disorder. We conclude that portal or hepatic venous thrombosis should be regarded as an index for 1 or several prothrombotic disorders, whether or not local precipitating factors or oral contraceptive use are found. Concurrence of prothrombotic disorders is more common than expected. Extensive investigation of prothrombotic disorders and anticoagulation should be considered in patients with portal or hepatic venous thrombosis.
 ...
PMID:Cause of portal or hepatic venous thrombosis in adults: the role of multiple concurrent factors. 1070 47

Evaluation of inherited thrombophilia in patients with venous thromboembolism includes testing for functional activity of antithrombin, protein C and protein S, and resistance to activated protein C (factor V Leiden), which can be assessed with plasma and DNA-based assays. The antiphospholipid syndrome is an acquired disorder related to the development of antibodies against phospholipid-protein complexes. Testing for the antiphospholipid syndrome includes measurement of antibodies to phospholipid-protein complexes by immunoassay or by detecting interference of anti-phospholipid antibodies in sensitive phospholipid-based assays. Other genetic risk factors have been listed, including a common polymorphism in prothrombin gene (3'-untranslated region) related to an increase of prothrombin level (> 115%) and a common polymorphism in the methylene tetrahydrofolate reductase (enzyme involved in homocysteine metabolism) gene related to a mild increase of homocysteine blood level. More recently high plasmatic levels of factor VIII (> 150%) or factor XI (> 120%), not related so far to a molecular defect, have been identified as risk factors for deep vein thrombosis. As a candidate gene, factor XIII gene polymorphisms are under investigation. Beside the acquired or genetic risk factors involved in thrombophilia, the gene-environment interactions are of importance in the onset of thrombosis.
 ...
PMID:[Laboratory testing for venous thromboembolism]. 1120 40

Environmental and genetic risk factors interact to cause venous thromboembolism. Renal vein thrombosis in the newborn has been frequently associated with "risk factors" as catheters, surgery or trauma, but it has also been demonstrated a pathogenetic role of genetic prothrombotic risk factors, i.e. activated protein C resistance and FV Leiden. The treatment of neonatal venous thrombosis varies worldwide and different approaches have been proposed. We present a case of renal vein thrombosis in a female newborn with normal plasma levels of protein C, protein S and antithrombin III, but with her genotype characterized by the presence of three prothrombotic risk factors: factor V Leiden, methylentetrahydrofolate reductase and platelet glycoprotein IIIa polymorphisms. The treatment with recombinant tissue plasminogen determined complete thrombus dissolution.
 ...
PMID:Renal vein thrombosis in a newborn with prothrombotic genetic risk factors. 1134 77

Congenital and acquired thrombophilia are associated with an increased risk of pregnancy-associated venous thrombosis and fetal loss. Two hundred eighty-nine patients with a history of recurrent spontaneous abortion were subjected to screening examinations for the etiology of these abortions. Endocrine abnormality (28.0%), uterine abnormality (10.4%), autoimmune diseases (1.4%), antiphospholipid antibody syndrome (4.5%), and balanced type chromosome translocation (4.2%) were found as underlying causes of recurrent abortions, and the remaining 55.0% of the 289 patients were classified as having an unexplained etiology. Congenital thrombophilia such as protein C (PC) deficiency, protein S (PS) deficiency, antithrombin deficiency, and factor V Leiden mutation was not frequently detected; only one patient had PS deficiency. A reduced factor XII activity was found at a frequency of 4.2%. The frequency of methylene tetrahydrofolate reductase gene C677T mutation in recurrent aborters (0.38) was the same as that found in a fertile control group. Although the prevalence of anti-beta2-glycoprotein I antibody (abeta2-GPI) syndrome was very low (1.7%), patients with a high titer of immunoglobulin G (IgG) class abeta2-GPI, despite anticoagulation therapy, experienced severe fetomaternal complications in subsequent pregnancies. The rate (13.8%) of positive tests for serum IgA class abeta2-GPI in patients with unexplained etiology was higher than that in the controls (0%) (P < .05). We conclude that congenital thrombophilia is rare in Japanese patients who had experienced consecutive spontaneous abortions.
 ...
PMID:Recurrent pregnancy loss: etiology of thrombophilia. 1137 65

A subgroup of children with arterial ischemic stroke in the pre- or perinatal period present with delayed diagnosis. We identified 22 children who met the following criteria: (1) normal neonatal neurological history, (2) hemiparesis and/or seizures first recognized after two months of age, and (3) computed tomography or magnetic resonance imaging showing remote cerebral infarct. Laboratory evaluations included protein C, protein S, antithrombin, activated protein C resistance screen (APCR), Factor V Leiden (FVL), prothrombin gene defect, methylene tetrahydrofolate reductase variant (MTHFR), anticardiolipin antibody (ACLA), and lupus anticoagulant. Not all children received all tests. Age at last visit ranged from 8 months to 16.5 years (median 4 years). Twelve were boys. Fourteen had left hemisphere infarcts. Median age at presentation was 6 months. Eighteen had gestational complications. Fourteen children had at least transient coagulation abnormalities (ACLA = 11, ACLA + APCR = 1, APCR = 2 with FVL + MTHFR = 1); six of these children had family histories suggestive of thrombosis. Cardiac echocardiogram was unremarkable in the 15 tested. Outcomes included persistent hemiparesis in 22; speech, behavior, or learning problems in 12; and persistent seizures in five, with no evidence of further stroke in any patient. The persistence and importance of coagulation abnormalities in this group need further study.
 ...
PMID:Presumed pre- or perinatal arterial ischemic stroke: risk factors and outcomes. 1150 98

We describe a 36-year-old man with familial protein S deficiency and homozygosity to the methylene tetrahydrofolate reductase (MTHFR) thermolabile variant who had a stroke followed by an episode of idiopathic osteonecrosis that was successfully managed by surgical core decompression. The patient's symptomatic thrombophilia, as well as that of several of his first-degree relatives who also had thrombotic events, raises the possibility that the thrombophilia was a contributing factor to the development of his osteonecrosis.
 ...
PMID:Idiopathic osteonecrosis in an adult with familial protein S deficiency and hyperhomocysteinemia. 1168 42

During an 18-month period, 10 consecutive Mexican mestizos with a dinical marker associated with a primary hypercoagulable state were studied. The assessment of the sticky platelet syndrome (SPS) was done by the method described by Mammen. In addition, the activated protein C resistance phenotype, coagulation protein C activity and antigen, coagulation protein S, antithrombin III, plasminogen, tissue-type plasminogen activator activity, plasminogen activator inhibitor activity, plasminogen activator inhibitor type 1, IgG and IgM isotypes of anti-phospholipid antibodies, homocysteine levels, the factor V gene Leiden mutation, the 677 C->T mutation in the 5,10-methylen-tetrahydrofolate-reductase (MTHFR), and the G20210A polymorphism in the 3'-untranslated region of the prothrombin gene were studied. Six patients with the SPS were identified: only one displayed this as the single thrombophilic abnormality; in five others, additional thrombosis-prone conditions were found: heterozygosity for the MTHFR 677 gene mutation in five cases; and, in one case each, heterozygosity for the factor V Leiden mutation, heterozygosity for the factor II G20210A mutation, and antiphospholipid antibodies in another. Four of the six patients had a family history of thrombophilia. All patients were treated with aspirin and no new vasoocclusive episodes have been recorded. SPS in not an infrequent finding in Mexican mestizo thrombophilic patients and may contribute to thrombophilia.
 ...
PMID:Primary thrombophilia in Mexico III: A prospective study of the sticky platelet syndrome. 1236 Dec 6

Familial multiple coagulation factor deficiency (FMFD) of factors II, VII, IX, X, protein C, and protein S is a very rare bleeding disorder with autosomal recessive inheritance. The phenotypic presentation is variable with respect to the residual activities of the affected proteins, its response to oral administration of vitamin K, and to the involvement of skeletal abnormalities. The disease may result either from a defective resorption/transport of vitamin K to the liver, or from a mutation in one of the genes encoding gamma-carboxylase or other proteins of the vitamin K cycle. We have recently presented clinical details of a Lebanese family and a German family with 10 and 4 individuals, respectively, where we proposed autosomal recessive inheritance of the FMFD phenotype. Biochemical investigations of vitamin K components in patients' serum showed a significantly increased level of vitamin K epoxide, thus suggesting a defect in one of the subunits of the vitamin K 2,3-epoxide reductase (VKOR) complex. We now have performed a genome-wide linkage analysis and found significant linkage of FMFD to chromosome 16. A total maximum 2-point LOD score of 3.4 at theta = 0 was obtained in the interval between markers D16S3131 on 16p12 and D16S419 on 16q21. In both families, patients were autozygous for 26 and 28 markers, respectively, in an interval of 3 centimorgans (cM). Assuming that FMFD and warfarin resistance are allelic, conserved synteny between human and mouse linkage groups would restrict the candidate gene interval to the centromeric region of the short arm of chromosome 16.
 ...
PMID:Homozygosity mapping of a second gene locus for hereditary combined deficiency of vitamin K-dependent clotting factors to the centromeric region of chromosome 16. 1238 21


1 2 3 4 5 6 7 8 Next >>