Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiotensin converting enzyme inhibitors are utilized in the treatment of essential hypertension and of chronic cardiac failure. They are also employed in the treatment of the myocardial lesion of ischemia-reperfusion, which involves oxygen free radicals. In the present study we investigated the possibility of three angiotensin converting enzyme inhibitors (captopril, enalapril, lisinopril) to act as hydroxyl radical scavengers. The rate constants for reactions of those compounds with .OH were determined using the deoxyribose method. All there compounds proved to be good scavengers of .OH with rate constants of about 10(10)M-1s-1 and are iron chelators specially enalapril. The fact that captopril possesses a thiol group does not confer an higher antioxidative capacity. These results suggest that scavenging of oxygen free radicals may be a possible mechanism contributing to the therapeutic effect of angiotensin converting enzyme inhibitors.
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PMID:[Angiotensin-converting enzyme inhibitors as neutralizers of hydroxyl radical]. 132 14

In the last 18 years, we have observed 24 cases of hypoparathyroidism (HPT) in beta-thalassemia major. At present, 4.5% of patients followed regularly in our department have this complication. HPT is thought to be mainly the consequence of iron deposition in the parathyroid glands. The age of our patients when HPT was diagnosed ranged from 11 to 24 years (mean 16.5 years). Their serum ferritin levels ranged from 810 to 15,200 ng/ml (mean 3,772 ng/ml). The severity of HPT varied widely. In only 3 patients was hypocalcemia severe with signs of tetany, seizures or cardiac failure. The onset of HPT was preceded or followed in most patients by other endocrine and/or cardiac complications. We found no clear relationship between HPT and serum ferritin levels in our patients, suggesting either an individual sensitivity to iron toxicity or early damage of the parathyroid gland before chelation had reduced the iron overload. However, the diagnosis of no new cases of HPT in the last 3 years coinciding with the much improved regime of chelation therapy suggests that chelation may have helped to prevent the development of HPT.
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PMID:Hypoparathyroidism in beta-thalassemia major. Clinical and laboratory observations in 24 patients. 146 90

Deferoxamine is still today the only preventive and curative treatment of transfusional hemochromatosis. It must be perfused daily, intravenously or subcutaneously, during several hours. Implantable infusion devices (Port-A-Cath) offer intravenous access, allowing to use higher doses, while avoiding local swelling due to subcutaneous injections. This device was inserted in 7 major thalassemic patients who presented with severe complications of iron overload, including 4 of them with signs of cardiac failure. Ferritinemias of all patients were lowered after intensifying iron chelation: cardiac function improved drastically in 2 patients. Devices were responsible for some complications: occlusion in one patient, local infections in two. This way of administration of desferal seems useful in patients with high ferritinemia and/or organic complications related to hemochromatosis.
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PMID:[Intensifying iron chelating therapy with desferrioxamine using implantable venous access catheters (Port-A-Cath)]. 161 Feb 70

During the period 1950-1985, a total of 179 cases of clinically overt hereditary haemochromatosis (HH) were registered in Denmark, 140 males and 39 females. Median age at diagnosis was 55 years (range 29-81). Diagnostic approaches, symptoms and physical signs at discovery are described. All patients had grade 3-4 liver haemosiderin iron, and cirrhosis was present in 84%. Serum (S-) transaminase was elevated in 92%, S-alkaline phosphatase in 47% and S-bilirubin in 23%, while plasma prothrombin time was below normal in 34%. Females had higher alkaline phosphatase than males (p less than 0.05). Bone marrow haemosiderin iron (n = 81) showed no relation to iron status indicators and was unsuitable as a diagnostic tool. Skin biopsy (n = 56) was positive for haemosiderin iron in 67% and for melanin in 57%, but was of limited value in the assessment of HH. Arthropathy was registered in 44%; arthralgias and clinical joint abnormalities occurred more frequently in females than in males (p less than 0.05). Latent diabetes mellitus was found in 34% and overt diabetes in 55%, being more frequent in males than in females (p less than 0.05). Other endocrine abnormalities were seen in 66%. Cardiac failure was observed in 9% and abnormal ECG in 35%. Males had higher haemoglobin (p less than 0.0001) and S-iron (p less than 0.01) than females, while S-transferrin, transferrin saturation, S-ferritin and mobilizable iron stores showed no significant sex differences. Median transferrin saturation was 87% (range 52-100); values greater than 62% were observed in 96% of the patients. Median S-ferritin was 3,400 micrograms/l (800-12,700) and median iron stores 14.8 g (4.5-36.4).
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PMID:Hereditary haemochromatosis in Denmark 1950-1985. Clinical, biochemical and histological features in 179 patients and 13 preclinical cases. 191 39

To determine whether survival of patients with beta-thalassemia major has been prolonged by management that utilizes hypertransfusion and chelation with deferoxamine, we analyzed longevity by the Kaplan-Meier product-limit method. Group 1 patients (n = 71) followed between 1960 and 1976 with a low-transfusion regimen (pretransfusion hemoglobin level 7 to 8 gm/dl) and no chelation had an estimated median age of survival of 17.4 years, whereas it was 31.0 years for group 2 subjects (n = 80), who began hypertransfusion between 1976 and 1978 (pretransfusion hemoglobin level 10.5 to 11.5 gm/dl) and chelation with deferoxamine (20 to 60 mg/kg per day) (p less than 0.0001). For 70 patients who were treated with hypertransfusion and deferoxamine, we had data to calculate the ratio of total milligrams of transfusional iron to cumulative grams of deferoxamine. The 24 patients who died had a total iron burden of greater than 1.05 gm/kg; the ratio for them exceeded 31. These patients were characterized by poor compliance with chelation or by late start of therapy, with inability to receive enough deferoxamine before death. Death was preceded by arrhythmia requiring therapy in all but one, and by cardiac failure in all. Of 41 similarly iron-loaded survivors, 33 had a ratio of less than 31; only three had an arrhythmia, and five had cardiac failure. We conclude that treatment with deferoxamine, when used in amounts proportional to iron burden, delayed cardiac complications and improved longevity.
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PMID:Prolonged survival in patients with beta-thalassemia major treated with deferoxamine. 200 28

25 cases of thalassaemia major were studied by 2D and M-mode echocardiography. A significantly increased (p less than 0.001) mean value (100.8 +/- 27.37 msec, range 80 to 140 msec) of A2-E (early relaxation period) interval on M-mode was observed in thalassemia in comparison to mean level (82.6 +/- 5.7, range 60 to 100 msec) of control population. No significant differences were noted in FS % (fractional shortening) and EF% (ejection fraction) when compared to corresponding normal values respectively. Mean serum iron concentration (142.2 +/- 29.1 micrograms/dl, range 102 to 192 micrograms/dl) was significantly higher in thalassaemia as compared to normal population (mean 106.3 +/- 11.4 micrograms/dl, range 75 to 120 micrograms/dl). There was also a direct correlation between serum iron concentration and A2-E interval. 11 patients (44%) showed abnormal A2-E interval but only 3 patients (12%) showed abnormal percentage of FS and EF. It is therefore concluded that A2-E interval will help to detect early left ventricular dysfunction much before overt and irreversible heart failure becomes manifest and which will also help to optimise transfusion and chelation therapy.
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PMID:An echo-cardiographic (M-mode & 2D) analysis of thalassaemia major. 235 4

The consequences of transfusional iron overload on left ventricular diastolic filling have never been investigated systematically in patients with thalassemia major. In the present study, the pattern of left ventricular filling was assessed by Doppler echocardiography in 32 patients with thalassemia major (age, 17 +/- 5 years) who had not experienced symptoms of heart failure and had normal left ventricular systolic function. Data were compared with those obtained in 32 age-matched and sex-matched normal subjects. An abnormal Doppler pattern of left ventricular filling with increased flow velocity at mitral valve opening followed by an abrupt and premature decrease of flow velocity in early diastole was identified in the patients with thalassemia. Peak flow velocity in early diastole was increased in patients compared with controls (90 +/- 10 vs. 81 +/- 15 cm/sec; p less than 0.01), and rate of deceleration of flow velocity after the early diastolic peak and the ratio between the early and late (atrial) peaks of flow velocity were also increased (1,050 +/- 325 vs. 762 +/- 193 cm/sec2 and 2.7 +/- 0.7 vs. 2.2 +/- 0.5, respectively; p less than 0.001), whereas flow velocity deceleration time was reduced (97 +/- 22 vs. 119 +/- 19 msec; p less than 0.001). This Doppler pattern of diastolic filling is usually described as "restrictive" and reflects a decrease in left ventricular chamber compliance. A restrictive pattern of left ventricular filling was also identified in the subgroup of 16 study patients who had undergone optimal iron chelation therapy with deferoxamine.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Restrictive diastolic abnormalities identified by Doppler echocardiography in patients with thalassemia major. 236 28

Iron catalysis is involved in the generation of the highly cytotoxic hydroxyl radical and in the chain reactions of subsequent lipid peroxidation that lead to irreversible membrane damage. Assuming that ischemically stored heart transplants may incur free radical injury at the time of reoxygenation, we assessed the effects of the iron chelator deferoxamine in 70 isolated isovolumic buffer-perfused rat hearts subjected to the following protocol: cardioplegic arrest; cold (2 degrees C) storage for 5 hours; global ischemia at 15 degrees C for 1 hour, intended to simulate the implantation procedure; and normothermic reperfusion for 1 additional hour. During poststorage ischemic arrest, the following techniques of myocardial protection were evaluated: hypothermia alone; high-pressure (60 cm H2O) cardioplegia given at 0, 30, and 55 minutes of arrest; low-pressure (30 cm H2O) cardioplegia given at 0 and 55 minutes of arrest; and low-pressure (30 cm H2O) cardioplegia only given at 55 minutes of arrest. Treated hearts had deferoxamine (6 mumol) added to the cardioplegic solution used throughout the experimental time course. Further, in the treated group subjected to the protocol of single cardioplegic delivery at end ischemia, deferoxamine was given both in the cardioplegic reperfusate and in the Krebs buffer over the 15 initial minutes of reflow. Based on comparisons of postreperfusion ventricular pressure development, maximal rate of rise of ventricular pressure, left ventricular compliance, and coronary flow, the best myocardial protection was afforded by deferoxamine given as an additive to single-dose cardioplegic solution at the end of arrest and to the reperfusate during the initial phase of reoxygenation. As the drug has no inotropic effect, its protective action is most likely related to a decrease in catalytic iron available for free radical production and lipid peroxidation. These results support the hypothesis that oxidative damage may contribute to donor heart failure and demonstrate that this form of damage can be efficiently acted upon by iron chelation. The clinical relevance of these data stems from the fact that deferoxamine is available for human use and might become an effective means of improving donor heart preservation in the setting of clinical heart transplantation.
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PMID:A promising approach for improving the recovery of heart transplants. Prevention of free radical injury through iron chelation by deferoxamine. 236 51

The occurrence of hepatocellular carcinoma in a 22-year-old man with thalassemia major is reported. As a result of transfusional hemochromatosis, this patient had already developed diabetes, hypogonadism, heart failure, and the sicca syndrome; he was serum and tissue HBsAg negative. Liver iron concentration measured postmortem was found to be 50 times normal. Multiply transfused patients are at risk of developing hepatocellular carcinoma. Serial measurements of serum alpha-fetoprotein should permit early detection of the tumor and reduce mortality. Preventive measures include early immunisation against hepatitis B virus and prevention of iron accumulation by intensive use of desferrioxamine. Treatment of hemochromatosis-associated hypogonadism with androgens should be considered with caution.
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PMID:Hepatocellular carcinoma in thalassemia major. 243 Dec 57

FeSO4 0.1-0.7 mmol/L shortened the action potential duration, decreased the action potential amplitude (APA) and maximal upstroke velocity of 0 phase (Vmax), and reduced the contractile force of myocardium in a concentration-dependent manner. FeSO4 0.2 mmol/L depressed the APA and Vmax of papillary muscles in Tyrode's solution containing MnCl2 3 mmol/L, and reduced the APA, Vmax and duration of slow action potentials in potassium-depolarized papillary muscles. These results suggest that Fe2+ may inhibit the transmembrane movement of Ca2+ and Na+ in myocardial cells. This may be one of the mechanisms of heart failure and circulatory collapse in acute iron poisoning.
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PMID:[Effects of FeSO4 on electrical and mechanical activity of guinea pig papillary muscles]. 264 50


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