Diseases heart

Rheumatic mitral valve disease is associated with thromboembolic complications at reported rates of 1.5 to 4.7% per year the incidence in patients with mitral stenosis is approximately 1.5 to 2 times that in patients with mitral regurgitation. The presence of atrial fibrillation is the single most important risk factor for thromboembolism in valvular disease, increasing the incidence of thromboembolism in both mitral stenosis and regurgitation four- to sevenfold. In current practice, patients with nonrheumatic atrial fibrillation at low risk for thromboembolism based on clinical characteristics frequently are treated with aspirin. Warfarin therapy is considered in higher-risk patients, especially those with previous thromboembolism and in whom anticoagulation is not contraindicated due to preexisting conditions. 

Most ischemic strokes are due to atherosclerotic cerebrovascular disease. Patients with symptomatic carotid stenosis of 70% should be considered for endarterectomy. Aspirin is used for prophylaxis following transient ischemic attacks and minor stroke. 

Coronary Heart Disease Several studies have linked mercury exposure to cardiovascular disease. These studies are important because consumers are advised to eat fish to protect against heart disease. Some fish species contain beneficial omega-3 fatty acids, and fish is also a low-fat source of protein. However, recent studies have raised the possibility that a moderate mercury content in fish may diminish the cardioprotective effect of fish intake in humans. Salonen et al. (2000) reported an association between moderate hair mercury content and accelerated progression of carotid arteriosclerosis in a prospective study among 1014 men aged 42-60 years in Finland. Hair mercury levels 2 pg g showed a doubling of the risk of 

The results of studies in humans on the immune reaction to elemental mercury vapor exposure have been inconsistent, with either increases or decreases in immune activity. In workers exposed occupationally to mercury vapor, a stimulation of T-lymphocytes, manifested by an increased number of T cells, T-helper cells and T-suppressor cells, was observed (Moszczynski et al. 1995). Further, a reduction in the number of B lymphocytes as of CD4+ lymphocytes in T cells was found in mercury vapor-exposed workers and, on the other hand, increased immunoglobulin E levels (Dantas and Queiroz 1997). Renal biopsies of two mercury-exposed workers who had developed proteinuria revealed deposits if IgG and complement C3 in the glomeruli (Tubbs et al. 1982). High anti-DNA antibody titers have been reported 

An autoimmune response to mercury vapor, such as increased levels of serum IgE and antilaminin autoantibodies, deposition of IgG deposits in the renal glomeruli and proteinuria was observed in a susceptible strain of rats (Hua et al. 1993, Druet et al. 

Autoimmune effects in the kidney, lung and spleen were also reported in rats exposed to HgCl2 aerosols (Bernaudin et al. 1981). Mercuric chloride can induce antinuclear antibodies in mice (Robinson et al. 1986), and glomerular nephritis in rats (Druet et al. 1978). No data are available on the effect of methylmercury on immune function in humans (NCR 2000, ERA 

Cell-culture studies on MeHg-exposed lymphocytes demonstrated an inhibition of mitogen-induced DNA synthesis, cell proliferation and antibody synthesis (Nakatsuru etal. 1985). Nuclear changes such as hyperchromaticity or fragmentation also occurred (Shenker et al. 1993). InTcells exposed to MeHg, the earliest adverse effects were detected in the mitochondria (Shenker et al. 1999). 

Many drugs and surgical techniques now in use are able to decrease the death rate and improve the quality of life for persons suffering from heart disease. However, heart disease remains the number-one killer of Americans. Known medically as cardiovascular disease, heart disease results from any condition that decreases the flow of blood, and consequently oxygen, to the heart or diminishes the ability of the heart to beat regularly and function in a normal 

The most common cause of heart disease is the plaque buildup on artery walls known as atherosclerosis, which was discussed in Section 16.4 in coryunction with the role of diet in plaque formation. If changes in lifestyle do not successfully combat this condition, the next step is cholesterol-lowering drugs, which include lovastatin and cholestyramine. Lovastatin acts by interfering with cholesterol synthesis in the liver. Cholestyramine acts by binding to bile acids in the intestines and accelerating their excretion. This causes the hver to convert more cholesterol into bUe acids, leaving less to enter the circulatory system. 

High blood pressure also contributes to heart disease. For this condition the next step after lifestyle changes is use of a diuretic, most commonly a thiazide (e.g., Diazide), which stimulates the production of urine and excretion of Na. With increased urine output, blood volume and consequendy blood pressure are decreased. 

The development of beta-blockers, drugs used to treat angina and other aspects of heart disease, illustrates how understanding the biochemistry of disease can lead to design of drugs. 

In the 1960s two types of receptors that are part of the natural regulatory system for heart rate were discovered and named beta-receptors. The beta-1 receptors are located primarily in the heart—stimulation of these sites speeds up the rate at which the heart beats. The beta-2 receptors are located in the peripheral blood vessels and the bronchial tubes. Stimulation of the beta-2 receptors relaxes muscle fibers, opening up the blood vessels and bronchial tubes so that blood flows more easily, making it easier to breathe deeply and quickly. These receptors are stimulated by the natural hormones epinephrine and norepinephrine during the fight-or- light response (Section 17.5). 

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Boyd D.P., Gould R.G., Quinu J.R, Sparks R., Stanly J.H., Herrmansfedt W.B. A proposed dynamic cardiac 3-D densitometer for early detection and evaluation of heart disease., IEEE Trans. Nucl. Sci., V. NS-26, 1979, p.2724-2727. 

Cholesterol is biosynthesized in the liver trans ported throughout the body to be used in a va riety of ways and returned to the liver where it serves as the biosynthetic precursor to other steroids But cholesterol is a lipid and isn t soluble in water How can it move through the blood if it doesn t dis solve in if The answer is that it doesn t dissolve but IS instead carried through the blood and tissues as part of a lipoprotein (lipid + protein = lipoprotein) The proteins that carry cholesterol from the liver are called low density lipoproteins or LDLs those that return it to the liver are the high-density lipoproteins or HDLs If too much cholesterol is being transported by LDL or too little by HDL the extra cholesterol builds up on the walls of the arteries caus mg atherosclerosis A thorough physical examination nowadays measures not only total cholesterol con centration but also the distribution between LDL and HDL cholesterol An elevated level of LDL cholesterol IS a risk factor for heart disease LDL cholesterol is bad cholesterol HDLs on the other hand remove excess cholesterol and are protective HDL cholesterol IS good cholesterol... 

Some scientific studies indicate that the gam in performance obtained through the use of anabolic steroids is small This may be a case though in which the anecdotal evidence of the athletes may be closer to the mark than the scientific studies The scientific studies are done under ethical conditions in which patients are treated with prescription level doses of steroids A 240 pound offensive tackle ( too small by todays standards) may take several ana bolic steroids at a time at 10-20 times their pre scribed doses in order to weigh the 280 pounds he (or his coach) feels is necessary The price athletes pay for gams in size and strength can be enormous This price includes emotional costs (friendships lost because of heightened aggressiveness) sterility testicular atro phy (the testes cease to function once the body starts to obtain a sufficient supply of testosterone like steroids from outside) and increased risk of prema ture death from liver cancer or heart disease... 

Low density lipoprotein (LDL) (Section 26 11) A protein which cames cholesterol from the liver through the blood to the tissues Elevated LDL levels are a nsk factor for heart disease LDL is often called bad cholesterol... 

Corn syrups [8029-43-4] Corn wet-milling Corn whiskey Coronadite [12414-82-3] Corona resistance Coronary bypass Coronary heart disease Coronates Coronavims Coronene [191-07-1] Coromte... 

Prior to this work, dietary fiber, of which ceUulose is oae of the more important constituents, was considered important primarily as a means of preventing or overcoming constipation. Otherwise, dietary fiber was considered to be a metaboHcally iaert substance. A large variety of diseases such as appendicitis, hiatus hernia, gallstones, ischemic heart disease, diabetes, obesity, dental caries, and duodenal ulcers are now suspected to be associated with the consumption of a highly refined diet (42). 

J. Stamler, in B. Rifkind, B. Dennis, and N. Ernst, eds.. Nutrition ofPipids and Corona Heart Diseases, Raven Books, New York, 1979, pp. 32—50. 

Other Calcium Disorders. In addition to hypocalcemia, tremors, osteoporosis, and muscle spasms (tetary), calcium deficiency can lead to rickets, osteomalacia, and possibly heart disease. These, as well as Paget s disease, can also result from faulty utilization of calcium. Calcium excess can lead to excess secretion of calcitonin, possible calcification of soft tissues, and kidney stones when combined with magnesium deficiency. 

OtherMa.gnesium Disorders. Neuromuscular irritabHity, convulsions, muscle tremors, mental changes such as confusion, disorientation, and haHucinations, heart disease, and kidney stones have aH been attributed to magnesium deficiency. Excess Mg " can lead to intoxication exemplified by drowsiness, stupor, and eventuaHy coma. 

Type of heart disease Prevalence Incidence MortaHty... 

There is a close correlation between myocardial infarctions and tachyarrhythmias, illustrated by the presence of complex ventricular arrhythmias among heart attack victims which are estimated to affect one-third of the survivors each year. Frequendy, the immediate cause of sudden death is ventricular fibrillation, an extreme arrhythmia that is difficult to detect or treat. In the majority of cases, victims have no prior indication of coronary heart disease. 

Nuclear medicine studies may reveal information that is primarily anatomic in nature, or indicate the function of an organ on a regional basis (Table 1). These studies may be intended to identify new disease, confirm or deny suspected disease, or foUow the progress of treatment or the course of disease. The diseases may be relatively benign or extremely serious and can range from widespread medical problems such as ischemic heart disease to rarities such as Legge-Perthe s disease and malignant pheochromocytoma (7). 

Technetium-9 9m sestamibi is used in myocardial perfusion imaging for the evaluation of ischemic heart disease. It is prepared from a lyophilized kit containing tetrakis(2-methoxy isobutyl isonittile) copper(I) tetrafluoroborate stored under nitrogen. Upon reconstitution with up to 5.6 GBq (150 mCi) of 99mTc pertechnetate, the product is formed by boiling for 10 minutes. 

Another example is the use of Tc-sestamibi, approved for use in the evaluation of coronary artery disease and myocardial infarction, in patients with breast cancer. Use in breast cancer is under investigation by a number of physicians. The data are not yet sufficient to determine the efficacy of this agent in this setting. Its safety, of course, has already been demonstrated as part of its initial evaluation for heart disease. 

In 1986, the FDA s Sugars Task Force assessed the impact of sugar consumption on human health and nutrition and concluded that sucrose is not an independent risk factor for heart disease, nor does it cause or contribute to the development of diabetes (62). Although diet is important after the onset of diabetes, sucrose can be well tolerated by insulin-dependent diabetics (63—65). 

Sugar is one of the purest foods made, from natural sources, and has never been known to contain any toxic or harmful components. Intensive investigations by the U.S. Food and Dmg Administration resulted in a book in 1986 on the health and safety factors of sugar (cane and beet) in the diet (18). The conclusion was that sugar has no deleterious effect on health in regard to heart disease, diabetes, or other metaboHc disorder. 

Corona.iy Hea.rt Disea.se, A theory for atherogenesis (120) has been developed whereby oxidation of low density Hpoprotein (LDL) within the arterial wall is the critical first step. It has been hypothesized that sufficient intake of antioxidants would prevent oxidation of LDL and reduce development of coronary heart disease (122). Interest in determining the role of antioxidants in blocking LDL oxidation has led to the development of in vitro test systems. 

Papaverine, used to treat heart diseases as a vasodilator, is a dmg that was originally made from vanillin but has since been made from veratrole and (9f2v (9-l,2-dimethoxybenzene. Vanillin is also used as a pharmaceutical excipient. 

Ascorbic acid also forms soluble chelate complexes with iron (142—145). It seems ascorbic acid has no effect on high iron levels found in people with iron overload (146). It is well known, in fact, that ascorbic acid in the presence of iron can exhibit either prooxidant or antioxidant effects, depending on the concentration used (147). The combination of citric acid and ascorbic acid may enhance the iron load in aging populations. Iron overload may be the most important common etiologic factor in the development of heart disease, cancer, diabetes, osteoporosis, arthritis, and possibly other disorders. The synergistic combination of citric acid and ascorbic acid needs further study, particularly because the iron overload produced may be correctable (147). 

Reduction in semm Hpids can contribute significantly to prevention of atherosclerosis. In 1985 a consensus report indicating that for every 1% reduction in semm cholesterol there is a 2% reduction in adverse effects of coronary heart disease was issued (145). Recommended semm cholesterol concentration was 200 mg/dL for individuals under 30 years of age, and individuals having concentration 240 mg/dL and LDL-cholesterol over 160 mg/dL should undertake dietary modification and possibly pharmacotherapy (146). Whereas the initial step in reducing semm cholesterol is through reduction of dietary cholesterol intake, a number of dmgs are available that can affect semm Hpid profile (see Fat substitutes). The pathway to cholesterol synthesis is shown in Figure 2. 

Hypertension is one of the two principal risk factors of many cardiovascular diseases, such as coronary heart disease (CHD), stroke, and CHF. Individuals are considered hypertensive if their systoHc arterial blood pressure is over 140 mm Hg (18.7 Pa) or their diastoHc arterial blood pressure is over 90 mm Hg (12 Pa). Over 60 million people, or one-third of the adult population in the United States are estimated to be hypertensive (163). About 90% of these patients are classified as primary or essential hypertensive because the etiology of their hypertension is unknown. It is generally agreed that there is a very strong genetic or hereditary component to this disease. 

In most situations, adequate, usuaHy forced, ventilation is necessary to prevent excessive exposure. Persons who drink alcohol excessively or have Hver, kidney, or heart diseases should be excluded from any exposure to carbon tetrachloride. AH individuals regularly exposed to carbon tetrachloride should receive periodic examinations by a physician acquainted with the occupational hazard involved. These examinations should include special attention to the kidneys and the Hver. There is no known specific antidote for carbon tetrachloride poisoning. Treatment is symptomatic and supportive. Alcohol, oHs, fats, and epinephrine should not be given to any person who has been exposed to carbon tetrachloride. FoHowing exposure, the individual should be kept under observation long enough to permit the physician to determine whether Hver or kidney injury has occurred. Artificial dialysis may be necessary in cases of severe renal faHure. 

A third study (85) enrolled 7825 hypertensive patients (55% males and 45% females) having diastoHc blood pressures (DBP) of 99—104 mm Hg (13—14 Pa) there were no placebo controls. Forty-six percent of the patients were assigned to SC antihypertensive dmg therapy, ie, step 1, chlorthaUdone step 2, reserpine [50-55-5] or methyldopa [555-30-6], and step 3, hydralazine [86-54-4]. Fifty-four percent of the patients were assigned to the usual care (UC) sources in the community. Significant reductions in DBP and in cardiovascular and noncardiovascular deaths were noted in both groups. In the SC group, deaths from ischemic heart disease increased 9%, and deaths from coronary heart disease (CHD) and acute myocardial infarctions were reduced 20 and 46%, respectively. 

Nowadays the one of the leading cause of death in industrial country is Heart Failure (HF). Under the pathological conditions (e.g., Ischemic Heart Disease (IHD)) the changes in the enzymes activity and ultrastructure of tissue were obtained. The behavior of trace elements may reflect the activity of different types of enzymes. Pathological changes affects only small area of tissue, hence the amount of samples is strictly limited. Thereby, nondestructive multielemental method SRXRF allow to perfonu the analysis of mass samples in a few milligrams, to save the samples, to investigate the elemental distribution on the sample area. 

The large difference in the mortality from respiratory and heart disease may have a simple explanation. Ammonium nitrate is explosive and the fertilizer workers were probably not allowed to smoke at work. 

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