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)

Essential trace elements such as zinc, iron, and copper participate in various enzyme reactions directly related to the regulation of blood pressure and indirectly related to generation of oxidative metabolic energy, alterations in blood lipid levels, and alterations in taste acuity. The toxicological action of several heavy metal ions including cadmium, lead, mercury, and thallium can cause hypertension by affecting hormone metabolism, vasoconstriction, and renal tubular function. We conclude, however, that neither deficiencies of essential elements nor the presence of toxic heavy metals are primary causes of hypertension in our population.
 ...
PMID:Trace elements and blood pressure. 684 20

An increased awareness of sodium's possible relation to hypertension has resulted in many Americans trying to avoid foods high in sodium without realizing the nutritional risks taken when these foods are eliminated from the diet. A recent study shows that a significant proportion of the population is consuming less than 66% of the recommended dietary allowance for calcium, iron, magnesium, and vitamin B6. Most of the population's daily sodium intake is from foods in the meat, grain, and milk food groups. Foods contributing sodium to the diet also contribute other essential nutrients currently consumed at inadequate levels by many Americans. There is a risk in reducing foods containing sodium from the diet without considering other nutrients. Emphasis should be on eliminating discretionary salt and selecting a balanced diet from the basic five food groups.
 ...
PMID:Nutritional consequences of reducing sodium intake. 684 27

The previously reported elevation of serum iron in association with toxemia of pregnancy was evaluated to determine if this chemical test could be clinically useful. When patients with toxemia and pregnant women with chronic hypertension were compared, a serum iron value greater than 100 micrograms/dl or an increase greater than 70% above baseline was a sensitive and specific indicator of toxemia. The predictive value is high and exceeds that of other commonly available tests. The clinical value of this model is discussed.
 ...
PMID:Clinical applications of the altered iron kinetics of toxemia of pregnancy. 685 80

Needs for virtually all nutrients increase during pregnancy and lactation but those for iron are the most difficult to meet from a normal diet. During pregnancy, nutritional objectives include helping the woman to increase the quality of her diet in protective nutrients as well as energy to meet the elevated needs of gestation, ensuring satisfactory weight gain patterns, prescribing iron and possible folic acid supplements, ensuring that intakes of alcohol, drugs, and other potentially harmful substances are moderate, preparing her for feeding the infant, and coping with any special diet-related problems that may arise. These issues and the management of edema, high blood pressure, and diabetes mellitus are discussed. Prenatal preparations for lactation and diet during lactation are also discussed. Specific objectives of nutritional education on lactation include helping the mother to make the decision to breast or bottle feed, taking steps to prepare her nipples if this is necessary and planning her diet. Dietary adjustments are discussed and a food guide presented. Iron supplements for ther lactating mother and iron, vitamin D, and fluoride supplements for the infant are recommended.
 ...
PMID:Nutritional support during pregnancy and lactation. 692 84

Weanling rats were fed a casein-based diet containing either 150 ppm cadmium, 500 ppm nickel, or the combination of these metals for 16 wk. Blood pressure of rats fed the diet with cadmium decreased after 8 wk, but this effect was counteracted by dietary nickel. Cadmium caused a depletion of iron and resulted in an accumulation of zinc in liver and kidney of rats. Nickel partially counteracted the iron loss due to cadmium. In a second experiment, the inclusion of 10 or 20 ppm cadmium in drinking water for 24 mo did not result in elevated blood pressure in normal or genetically hypertensive rats. Cadmium had no effect on the plasma renin levels in either experiment. Low intake of cadmium (10 or 20 ppm) in drinking water resulted in elevated cadmium content in hair. Thus, our data do not indicate that high levels of cadmium contribute to hypertension.
 ...
PMID:Cadmium and nickel influence on blood pressure, plasma renin, and tissue mineral concentrations. 698 93

Experimental hypertension in rats increases vascular permeability to tracers such as Trypan blue or colloidal iron. The amount of tracer which enters the tissues examined : brain, skin and aortic wall is proportional to the damage of the vascular wall. The highest permeability increase was seen in the aortic wall, then in the skin. Brain vessels seem to be the most resistant to permeability increase induced by experimental hypertension.
 ...
PMID:The early arterial effects of renovascular hypertension in rats. 703 98

This paper documents diagnosis and treatment of hypotension among a sample of subjects visiting blood pressure screening booths as part of a hypertension screening survey in Montreal. Of 1019 subjects, over one quarter had been diagnosed as hypotensive. Though low blood pressure is harmless for the majority of people, almost 10% of the screened sample reported receiving treatment from their physicians for the condition. Treatment typically consisted of harmless, but ineffective placebo-like medications including veal liver extract capsules or injections, iron capsules, tonics and vitamin B12 liquid, injections or capsules. Additional analysis discovered little meaningful difference in systolic and diastolic readings among individuals treated for hypotension, those diagnosed but not treated, and an undiagnosed group. Subjects receiving the hypotensive label from practitioners were typically older women with less education and income. Findings are discussed in light of the overlap between statistical and pathological models of illness; presenting symptoms of patients and their demands for treatment; and assumptions of physicians in diagnostic decision-making. It is speculated that medical definition of a nondisease such as low blood pressure may serve to individualize discomfort when true etiology lies in the environment; legitimate neglect of responsibilities and obligations by assigning one to the sick role; or cause organization of vague impulses into symptoms. Hypotension should be included in utilization studies to determine prevalence of treatment, life history of those being treated and complaints offered for treatment.
 ...
PMID:Treatment for a nondisease: the case of low blood pressure. 710 Sep 54

During the past decade the World Health Organization (WHO) has embarked on a $17 million program to study different kinds of contraceptive methods and their effect on maternal health. More than 600 scientists from 85 countries are participating. These investigations have implicated abortion as a factor in miscarriage, perinatal morbidity, and perinatal mortality due to isthmus-cervical inadequacy. It is also implicated in sterility and extrauterine pregnancy, as well as other disorders of pregnancy. Hence WHO emphasizes other birth control methods, in particular the pill. But the birth control pill also has side effects, as this is the first time that hormones have been used not to treat some illness but in healthy women. Their incidence increases with age (after 30-35 years of age) and also is enhanced by smoking, high blood pressure, hyperlipoproteinemia, and diabetes. Oral contraceptives (OCs) also reduce the incidence of benign tumors of the breast, ovarian cysts, iron-deficiency anemia, and rheumatoid arthritis. They have a beneficial effect also in endometriosis, dysfunctional hemorrhages, polyposis and endometrial hyperplasia, ovulatory problems, and inflammatory conditions of the genitals. Many of the longterm effects of these contraceptives are still unknown, such as their influence on cancer or on the fetus. The WHO investigation has shown that 1/2 stop taking the birth control pill after 1 year, and 2/3 after 2 years. Another widespread technique is the IUD, used by over 60 million women. But this causes hemorrhage in some, especially the women of India, Pakistan, and other countries. Work is now being done on ways to minimize the hemorrhage associated with the IUD, to clarify its presence as a cause of inflammatory processes of the genitals, extrauterine pregnancies, and subsequent sterility. The WHO also studied the rhythm method of preventing conception and found that 35% of women ceased employing it after 13 months, while 20% became pregnant. It was decided to work on elucidating new methods of determining the onset of ovulation. The WHO is also studying the use of prostaglandins to interrupt pregnancy. A major task for the future is determining which women are at greatest risk from the various birth control techniques.
 ...
PMID:[Modern methods of regulating generative function]. 733 55

Avoidance of homologous blood products and patients' demand for preoperative autologous blood donation programs are increasing. As many of these patients are older, with a compromised cardiovascular system and a slow response of the erythropoietic system when anemia occurs, the feasibility and benefit of autologous blood donation is often limited. Augmentation of preoperative blood donation by therapy with recombinant human erythropoietin (rHuEPO) has been described in animal models and in patients. METHODS. In a multicenter, controlled, randomized trial, 49 patients scheduled for orthopaedic or vascular surgery received 0 (control group, n = 9), 200 (n = 10), 300 (n = 11), 400 (n = 10) or 500 (n = 9) U/kg rHuEPO (Erypo, Cilag, Sulzbach, distributor Fresenius, Oberursel, Germany) subcutaneously twice a week for 3 weeks while every week 450 ml blood was collected. Iron sulphate 100 mg was prescribed orally twice a day. Patients were ineligible if they had uncontrolled hypertension, recent myocardial infarction, haematological disorders or a history of seizures. Blood donation had to be cancelled if the haematocrit was below 30%. RESULTS. There was a significant (ANOVA) drop of the haematocrit value only in the control group, and end-point values for haematocrit and haemoglobin were significantly elevated in the 400 and 500 U/kg groups compared with the control group (Table 9). DISCUSSION. The erythropoietic stimulus of phlebotomy for autologous blood donations is often not efficient enough to guarantee a constant haematocrit. Lowering of the preoperative haematocrit jeopardizes the aim of avoidance of homologous blood transfusions. rHuEPO increased the efficiency of autologous blood collections, as predonation haematocrit values could be preserved in the high-dosage groups. As a consequence, homologous transfusions could be avoided. However, there were broad interindividual differences in the erythropoietic response, possibly due to limitations in iron availability. Adverse effects of rHuEPO therapy, such as hypertension, thrombosis or neurologic disorders, are mostly reported in patients with terminal kidney failure. No such disturbances were observed in the present study. CONCLUSION. rHuEPO ameliorates the preoperative decrease of haemoglobin and haematocrit values due to autologous blood donations in a dose-related fashion. The individually adjusted dosage of rHuEPO and iron supplementation merits further investigation.
 ...
PMID:[Erythropoietin therapy during frequent autologous blood donations. Dose-finding study]. 748 23

Three isozymes of nitric oxide (NO) synthase (EC 1.14.13.39) have been identified and the cDNAs for these enzymes isolated. In humans, isozymes I (in neuronal and epithelial cells), II (in cytokine-induced cells), and III (in endothelial cells) are encoded for by three different genes located on chromosomes 12, 17, and 7, respectively. The deduced amino acid sequences of the human isozymes show less than 59% identity. Across species, amino acid sequences for each isoform are well conserved (> 90% for isoforms I and III, > 80% for isoform II). All isoforms use L-arginine and molecular oxygen as substrates and require the cofactors NADPH, 6(R)-5,6,7,8-tetrahydrobiopterin, flavin adenine dinucleotide, and flavin mononucleotide. They all bind calmodulin and contain heme. Isoform I is constitutively present in central and peripheral neuronal cells and certain epithelial cells. Its activity is regulated by Ca2+ and calmodulin. Its functions include long-term regulation of synaptic transmission in the central nervous system, central regulation of blood pressure, smooth muscle relaxation, and vasodilation via peripheral nitrergic nerves. It has also been implicated in neuronal death in cerebrovascular stroke. Expression of isoform II of NO synthase can be induced with lipopolysaccharide and cytokines in a multitude of different cells. Based on sequencing data there is no evidence for more than one inducible isozyme at this time. NO synthase II is not regulated by Ca2+; it produces large amounts of NO that has cytostatic effects on parasitic target cells by inhibiting iron-containing enzymes and causing DNA fragmentation. Induced NO synthase II is involved in the pathophysiology of autoimmune diseases and septic shock. Isoform III of NO synthase has been found mostly in endothelial cells. It is constitutively expressed, but expression can be enhanced, eg, by shear stress. Its activity is regulated by Ca2+ and calmodulin. NO from endothelial cells keeps blood vessels dilated, prevents the adhesion of platelets and white cells, and probably inhibits vascular smooth muscle proliferation.
Hypertension 1994 Jun
PMID:Nitric oxide synthase isozymes. Characterization, purification, molecular cloning, and functions. 751 53


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>