Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chemical diversity of estrogen and progestogen components of oral contraceptive (OC) products, their use alone or in combination, and the diversity of treatment regimens and doses account for the majority of contradictions in the immense literature on vascular and metabolic side effects of these hormones. OCs are exclusively composed of synthetic hormones. All OCs impose metabolic modifications on the organism and especially on the hepatic parenchyma due to delayed hepatic degradation. Certain factors increase the risk of vascular accidents associated with OC use: metabolic changes affecting coagulation, lipids, glucides, and arterial hypertension, immunologic phenomena, smoking, and obesity. As a whole, OCs affect coagulation by elevating factors 7 and 10, decreasing antithrombin iii (in high doses), and decreasing plasma fibrinolytic activity. synthetic estrogens cause an elevation of HDL cholesterol, a slight elevation of phospholipids, and a dose-dependent elevation of triglycerides and their VLDL fraction. As a group, progestogens tend to decrease the HDL fraction of cholesterol. Norethindrone is incapable of opposing the hypertriglyceridemic action of synthtic estrogens, while norgestrel partially opposes it. Lipid modifications provoked by combined OCs are a function of the nature and dosage of the components. Among hemodynamic modifications, synthetic estrogens cause elevations in renin substrate, plasma renin activity, angiotensin 2 and aldosterone. Synthetic progestogens may have various effects depending on type and dose, but they do not appear sufficient to cause hypertension unless other factors linked to individual predispositions are present. Microdoses of progestogens alone do not affect the renin-angiotensin-aldosterone system. Studies have also been conducted on the effect of OCs on cardiac function and on the vascular walls. Prospective studies suggest a relative risk of 3 for venous thromboembolic accidents among OC users, while retrospective studies suggest a relative risk of 4-11. Thromboembolic risk is directly correlated with the dose of synthetic estrogens. Recent studies indicate a relative risk of 3-5 for myocardial infarct and cerebral vascular accidents in OC users. Most studies have indicated a multiplier effect of OCs on preexisting risk factors, especially age and smoking. Prevention of vascular accidents is based on the prescription of smaller doses and careful observation of absolute and relative contraindications to OC use.
...
PMID:[Sex steroids and vascular risk]. 1233 12

The plasma thrombomodulin (TM) level, an indicator of systemic endothelial cell damage, was measured in spontaneously hypertensive rats (SHR), deoxycorticosteron acetate (DOCA)-induced hypertensive rats and normotensive Wistar-Kyoto (WKY) rats to clarify its changes in hypertension. Plasma TM levels, measured by enzyme-linked immuno-sorbent assay, decreased with aging (5-20-weeks-old) in both SHR and WKY, and they were lower in SHR than age-matched WKY in all ages examined. Deoxycorticosteron acetate-induced hypertensive WKY also showed decreased TM levels compared with normotensive WKY. Accelerated coagulation and fibrinolysis shown by the increases in thrombin-antithrombin complex (TAT) and D-dimer levels were observed in both groups of hypertensive rats. These results suggest that hypertension may decrease plasma TM levels and induce a hypercoagulable state in rats.
...
PMID:Hypertension associated with reduced plasma thrombomodulin levels and a hypercoagulable state in rats. 1261 20

Vasomotor function of vascular endothelium was studied in 62 patients with grade 1-2 hypertension with moderate and high added risk. Methods included study of brachial and middle cerebral artery endothelium dependent and independent vasodilation/vasoconstriction, measurement of plasma levels of nitric oxide metabolites (NO(n)-), endothelin-1, and antithrombin, as well as registration of their changes during vasomotor tests with calculation of integral indexes. Most patients with hypertension differed from controls by preponderance of vasoconstrictor over vasodilator reactions both in peripheral and cerebral vascular bed. At the same time patients with hypertension had pronounced dissociation between vasomotor responses of cerebral and peripheral vessels compared with subjects with normal blood pressure (p<0.05). Besides lowered basal level of NO(n)- and high concentration of endothelin-1 patients with hypertension were characterized by hyperreactivity of nitricoxidergic system, augmented lability of endothelin producing system, and impaired athrombogenecity of vascular endothelium. Complex assessment of vasomotor function of vascular endothelium by sequential vasoactive tests characterizes functional and metabolic activity of cerebral and peripheral vessels and can be used for improvement of risk stratification and monitoring of efficacy of treatment of patients with hypertension.
...
PMID:[Complex assessment of vasomotor function of vascular endothelium in patients with hypertension]. 1511 71

The present study was designed to evaluate prothrombotic risk profiles in 59 consecutively recruited white neonates with renal venous thrombosis (RVT). The rates of prothrombotic risk factors (PRs)-for example, the factor V (FV) 1691G> A mutation, the factor II (FII) 20210G> A variant, antithrombin (AT), protein C (PC), protein S (PS), elevated lipoprotein(a) (Lp(a)), total fasting plasma homocysteine (tHcy) levels, and anticardiolipin antibodies (ACAs)-were compared with those of 118 healthy control children. At onset, 32 (54.2%) of the 59 neonates showed underlying clinical conditions; 40 (67.8%) of them and 23 (85.2%) of the 27 infants with idiopathic RVT showed at least one PR. Univariate analysis revealed significantly elevated odds ratios/95% confidence intervals (ORs/95% CIs) for FV and Lp(a). Additionally, PC/AT deficiency and ACAs were found significantly more often in the patient group (P =.04). Multivariate analysis calculated significant ORs/95% CIs only for FV (OR, 9.4; 95% CI, 3.3-26.6) and elevated Lp(a) (OR, 7.6; 95% CI, 2.4-23.8). Of the 59 neonates investigated, 53 revealed renal atrophy, and 13 children additionally suffered from severe arterial hypertension. In conclusion, the present study demonstrates the significance of genetic PR-especially the FV mutation and elevated Lp(a)-for the etiology of neonatal RVT.
...
PMID:Renal venous thrombosis in neonates: prothrombotic risk factors and long-term follow-up. 1515 75

Pre-eclampsia is a pregnancy-specific syndrome of unknown aetiology, observed in 3 - 5% of all pregnancies, associated with pathological vascular lesions in multiple organs, activation of the coagulation system, and maternal multisystemic and fetal complications. Clinically, pre-eclampsia is characterised by the onset of hypertension, proteinuria and oedema, usually beginning in the third trimester. Conventionally, antihypertensive agents are the main pharmacological treatment. Recently, some studies have shown that the treatment of pre-eclampsia with antithrombin concentrate corrects the hypercoagulability and improves the fetal status and the perinatal outcome. No clear evidence supports the use of heparin. A conservative treatment of moderate- to- severe pre-eclampsia, based on the administration of antithrombin concentrate, may allow a significant prolongation of pregnancy and a better neonatal outcome, as well as fewer maternal complications.
...
PMID:Recent progress in the therapeutic management of pre-eclampsia. 1550 Mar 69

A lacunar infarct is defined as the occlusion of a single perforating artery. Certain researchers have proposed that patients with lacunar infarcts can be classified into two clinically distinct entities: patients with a single, symptomatic lacunar infarct, and patients with multiple lacunar infarcts together with hypertension and leukoaraiosis. The present study attempted to delineate the characteristics of lacunar infarcts and evaluate the validity of the aforementioned hypothesis. A total of 130 consecutive patients with first-time symptomatic lacunar infarct were studied. All patients were dichotomized into two groups according to two different kinds of models as follows. Model-1: patients with a single lacune and patients with multiple lacunes; and Model-2: patients with large lacune and patients with small lacune. Associated factors for the multiple lacune group compared with the single lacune group as well as the large lacune group compared with the small lacune group, were analyzed by multivariate logistic regression analysis. Associated factors included age, sex, hypertension, diabetes mellitus, dyslipidemia, smoking, extracranial and intra-cranial vascular lesions, extent of lacunes and white matter lesions, progression status and blood pressure in the acute stage, and coagulation markers such as fibrinogen, thrombin-antithrombin complex, D-dimer, beta-thromboglobulin, platelet factor 4. Results for Model-1: hypertension (age-and sex-adjusted OR: 2.58, p = 0.017) and elevated systolic blood pressure (>160mmHg for the mean value during the first post-ictal week; OR: 2.55, p = 0.016) were significantly associated with the multiple lacune group. Large lacunes (>10mm in diameter) were negatively associated with the multiple lacune group (OR: 0.38, p = 0.017). Association between confluent white matter lesions and the multiple lacune group approached significance (OR: 2.16, p = 0.056). Results for Model-2: female sex (OR: 0.39, p = 0.021), mild stenosis of intracranial and extracranial arteries (<25%) (intracranial; OR: 5.42, p = 0.0042, extracranial; OR: 3.30, p = 0.016), progressing stroke (OR: 6.77, p<0.0001), and high levels of TAT (>3ng/ml) (OR: 2.80, p = 0.039) were significantly associated with the large lacune group. Multiple lacunes (OR: 0.38, p = 0.016) and confluent white matter lesions (OR: 0.28, p = 0.007) exhibited a significant negative association with the large lacune group. In conclusion, underlying vasculopathy in the presence of multiple lacunes may correspond to lipohyalinosis resulting from hypertension. Moreover, large lacune may correspond to microatheroma at the orifice of penetrating arteries.
...
PMID:[Clinical classification for lacunar infarct. An investigation of 130 consecutive cases of lacunar infarctions]. 1571 93

Previous studies have shown an increased risk of retinal vein occlusion (RVO) in patients with hypertension, hypercholesterolemia and diabetes mellitus. Literature on the association between thrombophilic factors and RVO consists of small studies and case reports. The objective was to determine the relationship between thrombophilic risk factors and RVO. Thrombophilic risk factors analyzed were hyperhomocysteinemia, MTHFR gene mutation, factor V Leiden mutation, protein C and S deficiency, antithrombin deficiency, prothrombin gene mutation, anticardiolipin antibodies and lupus anticoagulant. For all currently known thrombophilic risk factors odds ratios for RVO were calculated as estimates of relative risk. The odds ratios were 8.9 (95% CI 5.7 - 13.7) for hyperhomocysteinemia, 3.9 (95% CI 2.3 - 6.7) for anticardiolipin antibodies, 1.2 (95% CI 0.9 - 1.6) for MTHFR, 1.5 (95% CI 1.0 - 2.2) for factor V Leiden mutation and 1.6 (95% CI 0.8 - 3.2) for prothrombin gene mutation. In conclusion, regarding thrombophilic risk factors and RVO there is only evidence for an association with hyperhomocysteinemia and anticardiolipin antibodies, factors that are known as risk factors for venous thrombosis as well as for arterial vascular disease. The minor effect of factor V Leiden mutation and the protrombin gene mutation (risk factors for venous thrombosis only) suggests that atherosclerosis might be an important factor in the development of CRVO.
...
PMID:Retinal vein occlusion: a form of venous thrombosis or a complication of atherosclerosis? A meta-analysis of thrombophilic factors. 1596 81

Retinal vein occlusion (RVO) is a multifactorial disease involving vessel damage, stasis, viscosity and thrombosis. Conflicting findings on hereditary thrombophilic risk factors have been reported and their impact on RVO features remains to be defined. The aim of the present study was to evaluate the prevalence of hereditary thrombophilic risk factors (HTRF) and characteristics of RVO in patients with or without HTRF. The design of the study was a prospective, observational case series. Two hundred and thirty-four patients with RVO were included consecutively. A French healthy population of the same region was studied as control group. The HTRF studied were protein C (PC), protein S (PS) and antithrombin (AT) deficiencies, factor V Leiden (FVL) and factor II 20210A polymorphisms. Chi-Square was used for comparison with the healthy subjects and between RVO patient with and without HTRF according to localisation (branch vs. central), type of RVO (ischemic or non-ischemic), recurrence, age at first event and classical vascular risk factors. Twenty-two patients had HTRF (12 FV Leiden heterozygotes, 9 FII 20210A heterozygotes and 1 PS deficiency). No AT or PC deficiency was detected. Frequencies of PS deficiency, FVL and FII 20210A allele were similar to the reference population as well as to published data in the general caucasian population. Eighty-six patients experienced their first episode before the age of 60 years. Systemic hypertension, glaucoma and angina were significantly less frequent in patients with RVO before 60 years. Fourteen of the 22 patients with one HTRF (64%) experienced their first episode of RVO before the age of 60 years compared to 72 of 212 without HTRF (34%) (p = 0.006). Heterozygote status for FV Leiden was significantly more frequent in patients who had experienced their first episode of RVO before 60 years (p = 0.027). In conclusion, this study suggests a role of FV Leiden in the occurrence of RVO in patients younger than 60 years who exhibit fewer acquired vascular risk factors than in older patients.
...
PMID:Increased prevalence of factor V Leiden in patients with retinal vein occlusion and under 60 years of age. 1611 92

The role of thrombophilia in the pathogenesis of preeclampsia is controversial. The aim of this case-controlled study was to determine whether thrombophilia increases the risk of preeclampsia or interferes with its clinical course. A total of 808 white patients who developed preeclampsia (cases) and 808 women with previous uneventful pregnancies (controls) matched for age and parity were evaluated for inherited and acquired thrombophilia (factor V Leiden; factor II G20210A; methylenetetrahydrofolate reductase C677T; protein S, protein C, and antithrombin III deficiency; anticardiolipin antibodies; lupus anticoagulant; and hyperhomocysteinemia). Odds ratios (ORs) with 95% confidence intervals (CIs) for risk of being carriers of thrombophilia in cases compared with controls and for risk of maternal life-threatening complications and adverse perinatal outcomes in preeclamptic patients with or without thrombophilia were calculated. Women with severe preeclampsia (406 cases) had a higher risk (OR, 4.9; 95% CI, 3.5 to 6.9) of being carriers of either an inherited or acquired thrombophilic factor, except for protein S, protein C, and antithrombin deficiency. In women with mild preeclampsia (402 cases), only prothrombin and homozygous methylenetetrahydrofolate reductase gene mutations were significantly more prevalent than in the controls. Thrombophilic patients with severe preeclampsia are at increased risk of acute renal failure (OR, 1.8; 95% CI, 1.5 to 2.2), disseminated intravascular coagulation (OR, 2.7; 95% CI, 1.1 to 6.4), abruptio placentae (OR, 2.6; 95% CI, 1.2 to 6.0) and perinatal mortality (OR, 1.7; 95% CI, 1.5 to 2.2) compared with nonthrombophilic preeclamptic patients. Our study demonstrates a significant association between maternal thrombophilia and severe preeclampsia in white women. Thrombophilia also augments the risk of life-threatening maternal complications and adverse perinatal outcomes in preeclamptic patients.
Hypertension 2005 Dec
PMID:Thrombophilia is significantly associated with severe preeclampsia: results of a large-scale, case-controlled study. 1628 82

Kidney transplant recipients are prone to hypertension, dyslipidemia, and cardiovascular death. Hypertension is associated with hemostatic abnormalities. Thrombin activatable fibrinolysis inhibitor (TAFI) is a glycoprotein that links coagulation and fibrinolysis. The purpose of this study was to assess TAFI concentrations in renal transplant recipients in relation to blood pressure. Additionally, we evaluated thrombin activity (thrombin-antithrombin complex [TAT], prothrombin fragments 1+2 [F1+2]), thrombomodulin (TM), and the degree of plasmin generation (plasmin-antiplasmin complex [PAP]) using commercially available kits. The studies were performed on 86 renal allograft recipients (48 women, 38 men) at age range 26 to 73 years. The immunosuppressive regimen consisted of cyclosporine (CsA), prednisone, and azathioprine (n = 58) or mycophenolate mofetil (MMF; n = 28). All patients maintained sufficient and stable graft function, showing no clinical signs of rejection. In patients with hypertension (n = 68), we observed significantly higher concentrations of TAFI and of markers of thrombin generation (F1+2, TAT), and of thrombomodulin with significantly prolonged euglobulin clot lysis time (ECLT), which reflects overall fibrinolytic activity and lower fibrinolytic activity index (FAI). Both groups did not differ with respect to age, creatinine clearance, body mass index, time after transplantation, albumin, fibrinogen, and PAP. Diastolic blood pressure correlated significantly with TAFI concentrations, uric acid, and prednisone dose, whereas systolic blood pressure correlated with urea, uric acid, creatinine clearance, and MCV. Elevated TAFI concentrations and enhanced thrombin generation in hypertensive kidney transplant recipients may contribute to the hypofibrinolysis and progressive atherosclerosis in this population. Blood pressure was related to kidney function, maintenance prednisone dose, and TAFI concentration.
...
PMID:Thrombin activatable fibrinolysis inhibitor in hypertensive kidney transplant recipients. 1650 76


<< Previous 1 2 3 4 5 6 Next >>