However purchase cefixime 200mg line, if surgery is delayed several hours generic 100mg cefixime overnight delivery, his con- dition will worsen and he will end up brain dead buy cheap cefixime 100mg on-line. His organs can then be used to save the lives of five other upstanding citizens who very much want to live but who otherwise would die of organ failure. We would certainly judge that any transplant surgeon who took advantage of a situation like this would be doing something grossly unethical. Someone might argue in response that there is a major disanalogy between this case and our Edward-like gene therapy case (where Edward is denied access to a clinical trial because of some co-morbid condition), namely, that our skid row bum is negligently harmed by delaying the surgery that will certainly benefit him. Edward is not treated negligently; he is simply being denied the opportunity to benefit from access to the trial. Edward will be denied access to the clinical trial because of a co-morbid condi- tion on the grounds that the quality of the clinical data might be corrupted by his participation. But the harm that we would hope to avoid there is potential, remote, maybe best described as “speculative” since we cannot assign any specific proba- bility to the likelihood of that occurring. Even from a utilitarian point of view, the argument goes, should not such devastating harm to an individual be given greater moral weight than remote and speculative possibilities of harm to possible individuals far in the future? We do sometimes make such judgments in medicine, invoking what is referred to as the rule of rescue analogy. Are these clinical trials for gene therapy one of those circumstances in which this rule is justifiably invoked? We move now to our third issue that arises in connection with our principle of justice. To set the stage for that issue we need to make explicit an assumption that has been silently operative in our two prior justice problems. Specifically, we have assumed that these clinical gene therapy trials are more likely than not going to have a therapeutic outcome. That assumption probably reflects characteristic American optimism about our scientific endeavors. But strictly speaking we are not entitled to that assumption, especially in the earliest stages of clinical trials. And, in some circumstances, it might be more appropriate to have a serious concern about poten- tial harms. That in fact is what motivated the early ethical discussions about medical experimentation. There were the Nazi medical experiments, which are best seen as being maliciously motivated. But then there were also the Tuskegee experiments that involved African-American men who were allowed to go untreated for their syphilis, even after we had penicillin that would have cured them. The argument given for non- treatment was that we were in the middle of a medical experiment that we had to allow to run its course for the sake of scientific knowledge. This would be another clear case where invoking utilitarian considerations would not be ethically justified. The more serious point is that in the case of Tuskegee, and in the case of Willowbrook (retarded children and orphans), and in the case of the Jewish Hospital in New York (old senile patients), socially disfavored groups were used as experimental material for risky medical interven- tions. That is, these were individuals who were captives of institutions who were not in a position to give free and informed consent to assume the risks associated with these medical experiments. There was an imposition of risks and burdens on these individuals for the sake of benefits that would go to other individuals. The motivations of the medical researchers may not have been ethically corrupt, as in the Nazi case, but the outcomes were nevertheless strongly morally objectionable. These are concerns that we need to be mindful of in the case of gene therapy as well. Appropriate Candidates for Gene Therapy We now turn to another dimension of ethics issues in gene therapy, namely, who the candidates are for therapy. We start with competent adults, and we begin by noting that we are using the term competence in its accepted meaning in medical ethics as opposed to law. If an individual is generally capable of managing the tasks of daily life for himself, then he is competent. If not, then he is incompetent, and a guardian may be appointed to act on that person’s behalf. The relevant moral question is: Is this patient capable of processing information relevant to the decision at hand in such a way that it would be reasonable to conclude that they are making an autonomous choice? That is, are they capable of giving free and informed consent to this inter- vention? Can we be morally confident that they have no gross misunderstandings of the risks and benefits associated with this intervention? Perhaps the two most common would be (1) an excessively optimistic view of what participation in the experimental therapy might yield for them; and (2) in those cases where the trial is structured as a double-blind randomized controlled study, a failure to appreciate that there is a 50% chance that they would not receive the therapy they might expect. The ethical obligation of researchers in these circumstances is to correct these misconceptions so that such patients are making autonomous decisions to participate. In standard medical practice we need to rely upon surrogate decision makers to make medical decisions for incom- petent patients. Usually we are talking about close family members, and usually we can be confident that these surrogate decision makers are loyal, caring, and trust- worthy, that is, not likely to make deliberately a medical decision for this patient that would be contrary to the best interests of this patient. Again, in ordinary medical practice such surrogates are asked to make substituted judgments. That is, they are asked to make a decision as much as they can from the point of view of the patient, a point of view that best captures the stable goals and values of that patient, as opposed to any decision they might make for themselves were they in the patient’s situation. In practice this is not an easy criterion to use or to know with confidence it is being used correctly. The alternate ethical standard is a best- interests test, which means the surrogate is asked to judge whether the benefits of the proposed treatment outweigh the burdens for the patient or vice versa. In exper- imental medicine both standards can be very difficult to apply with confidence. It will rarely have been the case that patients (now incompetent) had the opportunity to think about the sorts of decisions they would make for themselves if offered the opportunity to be part of a medical trial. It is also more difficult to apply meaning- fully the best-interests test because the starting point for such medical interventions is clinical equipoise. Researchers simply do not know whether that intervention will yield a net benefit for that patient, nor do they know more than very imprecisely the range of risks to which that patient may be exposed. A reasonable ethical con- clusion to draw from this is that in general incompetent patients should not be included in clinical trials. We will modify the cases by reducing the age of each to 8, and attributing to them no more than average intelligence. So from a moral point of view they are clearly thought of as incompetent patients, which means their parents will have to make decisions for them. The primary reason is that Donald’s disease process is well managed; and hence, it would be difficult to justify the risks that this child would be assuming. By waiting several years he will likely have access to a better understood intervention more likely to yield actual benefit. His parents might want him to have “every oppor- tunity for a normal life,” but that reasonable desire may not be sufficient to justify their choosing those risks for him. By way of contrast, our revised Edward patient is faced with a terminal prognosis for his cancer. In such circumstances parents may assume for their children a greater level of risk on the grounds that this is the only way to protect the long-term best interests of those children. We should be clear, however, that such tragic circumstances do not warrant parents exposing their chil- dren to any level of risk whatsoever. If the failure of the gene therapy is not likely to alter significantly either the quality of life or length of life for that child, then it is justifiable to consider him for the therapy. But if the experimental therapy itself would add to the suffering of that child and yield a worse death, then it is just as clear that it would be morally wrong to consider such a child for this experimental therapy. The sort of case we have in mind would be an extremely aggressive form of chemotherapy, examples of which have drawn media attention in the recent past. The other sort of patient that deserves separate moral consideration would be fetuses. Such cases are complicated by the fact that the fetus is medically accessible only through the mother, which means specific medical interventions intended for the benefit of the fetus may put her at risk as well. We are all mindful of the fact that there have been several major efforts aimed at fetal therapy in the past few years, often fetal surgery. It may be the case that there will be comparable efforts to employ gene therapy in comparable circumstances.

Aviculture and veterinary problems vestigations of visual defects in rap- thalmology 100mg cefixime with visa. A punctate or grid effective in controlling the uveitis in this keratotomy to restore normal epitheliza- case (courtesy of S buy 200mg cefixime overnight delivery. These changes are charac- responded to treatment with topical keto- teristic of uveitis not complicated by hy- conazole (courtesy of S purchase cefixime 200 mg with mastercard. Phitisis bulbi with tion with topical steroid medication was wrinkling of the lid margins are also evi- slow and several synechiae remained. In this case, the contralateral An adult male cockatiel was presented with a three-week history of ocular discharge eye was unaffected, the bird’s behavior was normal and surgical removal of the and scratching of the face. A severe pan- ophthalmitis was noted on physical exami- cataract was not attempted (courtesy of K. The bird was tillating appearance of the cataract, indi- placed on systemic and ophthalmic antibi- cating some resorption. Extracapsular enucleation was performed six days after cataract extraction was performed and the initial presentation. Avian Pathol 15:687-695, Am Vet Med Assoc 183:1232-1233, men einer konjuntivitis unbekannter 53. J Amazon parrots (Amazona aestiva) he avian heart is divided into four complete chambers and is located midway in the tho- racic cavity in an indention in the sternum C H A P T E R T 50,91 parallel to the long axis of the body. The left ventricle is heavily walled and is about two to three times thicker than 27 the right. The right ventricle works as a volume pump and responds rapidly to an increased workload by dilation and hypertrophy. Rigor mortis may not occur if severe degenerative disease of the myocardium is present. The normal pericardial sac is clear and in contact with the epicardium circumferentially and the mediasti- nal pleura dorsally (see Color 13). A normal bird should have a small quantity of clear to slightly yellow fluid in the pericardial sac (see Color 14). Ritchie their internal structure is simple, lacking the T-tu- bules found in mammals. The small surface area precludes the need for a complex T-tubule system for excitation to occur. The increased cardiac output requires a higher cally separates the atria from the ventricles by pene- arterial pressure to produce higher blood flow rates. There are also fibers running to in general have a bigger heart than larger birds. Electrical conduction in Purkinje fibers is The aorta in birds is derived embryologically from about five times faster than in normal cardiac muscle the right fourth arterial arch and right dorsal aorta cells and hence the conduction system plays an im- and therefore the ascending aorta curves to the right portant role in regulating myocardial contraction. This structure can After transmission of the electrical impulses through be clearly seen radiographically on a ventrodorsal the ventricular conduction system, all areas of the projection. Blood is returned to the heart from the ventricles are activated in a coordinated fashion. Birds have a mean electrical axis that is negative, while the mean electrical axis in dogs is positive. This difference can be explained by the fact that in birds, the depolarization wave of the ventricles begins subepicardially and spreads through the myocar- dium to the endocardium, while in the dog, depolari- Evaluating the Avian Heart zation of the ventricles starts subendocardially. Electrical impulses are transported 1726 mixed avian species necropsied in one zoologi- along ordinary muscle fibers in the interatrial sep- cal collection. Subtle interatrial septum or the caudodorsal part of the murmurs are easiest to detect when birds are under interventricular septum. Auscultation of the heart can best be per- cardiovascular shunt as the cause of severe dyspnea formed on the left and right ventral thorax. The proce- or pulmonary fluid accumulation may cause muffled dure is performed by injecting a bolus dose of con- lung sounds or rales when a bird is auscultated over trast medium into the catheterized basilic vein. Of the imaging techniques, echocardiograms gener- Mild stress, such as occurs in the veterinary exami- ally provide the most diagnostic information. Echo- nation room or following restraint, may cause a bird’s cardiography was used successfully to detect valvu- heart rate to increase substantially (two to three lar endocarditis on the aortic valve of a four-year-old times normal). Staphylo- stress factors, drug exposure, toxins, diet, percent coccus was isolated from the vegetative lesion, which body fat and blood pressure can all alter the avian was seen as a large mass using this technique. As a rule, the heart rate in a bird that is small birds, the echocardiographic image of the heart being restrained is higher than the heart rate ob- is best obtained by sweeping through the liver. Color tained in the same bird if the rate had been deter- flow doppler was used to demonstrate mitral regur- mined using telemetry. Radiographic detection of cardiovascular abnormali- ties may be difficult, although an enlarged cardiac It was demonstrated in 1949 that the negative mean silhouette or microcardia can often be visualized. Other radiographic changes that suggest cardiac disease include congestion of Despite its great clinical applicability, electrocardiog- pulmonary vessels, pulmonary edema, pleural effu- raphy has received relatively little attention from sion, hepatomegaly and ascites. This might be due to the scarcity of electrocardiographic refer- Non-selective angiocardiography with rapid se- ence values in companion birds. To the authors’ quence serial radiographs has been used to confirm knowledge these values have been established only impaired cardiac function in a racing pigeon (Figure in racing pigeons, African Grey Parrots and Amazon 27. The eyes were glazed and partially closed, the ulnar vein refill time was two seconds, and the skin on the toes would stay elevated for several seconds when pinched. The lateral radiograph indicated microcardia (indicative of dehydration) and gaseous dis- tention of the proventriculus (open arrows), which is common in birds that are anesthetized or are severely dyspneic. A single rapid intravenous bolus of contrast agent was administered via a catheter into the cutaneous ulnar vein of a normal Green-winged Macaw. The axillary vein (arrow), cranial vena cava (c), cardiac chambers and pulmonary arteries (open arrows) are clearly visible. Note that contrast media is also present in the kidneys (courtesy of Marjorie McMillan). Regardless of the type of electrocardiograph used, it Electrocardiography may be useful for detecting car- must be able to run electrocardiograms at a paper diac enlargement from hypertrophy of any of the four speed of at least 100 mm/s. Electrocardiography is indispen- rapid that inspecting and measuring the tracing is sable for the diagnosis and treatment of cardiac ar- less accurate at slower speeds. If the complexes When evaluating cardiac enlargement it is best to are so large that they exceed the edge of the tracing compare the electrocardiographic findings with those paper, the sensitivity should be halved. Metabolic, cardiac, neurologic and systemic thetized racing pigeon that is restrained in an up- diseases that produce toxemia can cause one or all of right position, while in parrots, isoflurane anesthesia these clinical changes. When comparing anesthetized and be used also to monitor heart rate and rhythm in an unanesthetized parrots, only the median heart rate anesthetized patient. Needle electrodes placed subcutaneously are superior to alligator clips for use in avian patients. The P-wave signifies that the atria have depolarized, causing contraction and ejection of their complement of blood into the ventricles. In dogs, this is caused by right atrial hypertrophy and is called auricular T-wave or Ta-wave. If the vector runs perpendicular sent, it is often elevated above the baseline (maxi- to a lead, that lead will record either no deflection or mum 0. This malian species, these changes are associated with is called an isoelectric lead. When the electrocardiograph is recorded at Diagnose primary heart disease a paper speed of 100 mm/s, each small box on the Monitor therapy of heart disease horizontal is 0. If the vector runs perpendicular to a lead, that lead will record either no deflection or an equal number of positive and negative forces. Now there are six leads, with a positive and a negative pole, and each In theory, these three leads form an equilateral tri- pole has an angle value. The three leads can be redrawn exactly at the for determining the mean electrical axis of ventricu- same length and polarity by passing each lead lar depolarization (see Figure 27. An augmented unipo- Determination of Heart Rate lar lead compares the electrical activity of the refer- All recording paper has a series of marks at the top ence limb to the sum of the electrical activity at the or bottom of the paper. A second method of determining heart rate per minute is to count the number of small boxes from S-wave to S-wave and divide into 1500 (there are 1500 small boxes per minute at 25 mm/s paper speed). Determination of Heart Rhythm Is the heart rate normal or abnormal for the spe- cies (bradycardia or tachycardia)? Determination of Mean Electrical Axis To determine the heart axis, the mean wave of elec- trical activity in the frontal plane that occurs when the ventricles depolarize is meas- ured. The procedure for a rough esti- mation of the axis is simple and in- volves three steps (Figure 27. Use the six-axis reference system chart and find which lead is per- pendicular to the isoelectric lead (see Figure 27.

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Remember buy discount cefixime 100mg line, the creative guidance mechanism within you is a goal-striving mech- anism generic 200mg cefixime overnight delivery, and the first requisite for using it is to have a clear- cut goal or target to shoot for buy cefixime 100 mg without prescription. A great many people want to "improve" themselves, and long for a "better person- ality," who have no clear-cut idea of the direction in which improvement lies, nor what constitutes a "good personality. Time and again, I have seen confused and unhappy people "straighten themselves out," when they were given a goal to shoot for and a straight course to follow. They find themselves in a new role, and are not sure what kind of a person they are supposed to "be" in order to live up to that role. The Picture of Success In this chapter I am going to give you the same "pre- scription" that I would give you should you come to my office. He was like the skipper of a ship who had relinquished his hold upon the wheel, and hoped that he would drift in the right direction. He was like a mountain climber, who as long as he looked upward to the peak he wished to scale, felt and acted courageously and boldly. But when he got to the top, he felt there was nowhere else to go, and began to look down, and became afraid. He was now on the defensive, defending his present position, rather than acting like a goal-striver and going on the offensive to attain his goal. He regained control when he set himself new goals and began to think in terms of, "What do I want out of this job? Your trouble is you are trying to maintain your balance sitting still, with no place to go. When we have no personal goal which we are interested in and which "means something" to us, we are apt to "go around in circles," feel "lost" and find life itself "aimless," and "purposeless. People who say that life is not worthwhile are really saying that they themselves have no personal goals which are worthwhile. Get interested in some project to help your fellow man—not out of a sense of duty, but because you want to. You cannot react appropriately if the information you act upon is faulty or misunderstood. To deal effectively with a problem, you must have some understanding of its true nature. He is merely responding appropriately to what—to him—seems to be the truth about the situation. To give the other person credit for be- ing sincere, if mistaken, rather than willful and malicious, can do much to smooth out human relations and bring about better understanding between people. Opinion Many times we create confusion when we add our own opinion to facts and come up with the wrong con- clusion. When she stopped reacting just as if she had been personally insulted, she was able to pause, analyze the situation, and select an appropriate response. Be Willing to See the Truth Oftentimes, we color incoming sensory data by our own fears, anxieties, or desires. But to deal effectively with environment we must be willing to acknowledge the truth about it. We do not like to admit to ourselves our errors, mistakes, shortcomings, or ever admit we have been in the wrong. We do not like to acknowledge that a situation is other than we would like it to be. Someone has said that it is a good exercise to daily admit one painful fact about ourselves to ourselves. The Success-type personality not only does not cheat and lie to other people, he learns to be honest with himself. What we call "sincerity" is itself based upon self-understanding and self-honesty. For no man can be sincere who lies to himself by "rationalizing," or telling himself "rational- lies. In dealing with other people try to see the situation from their point of view as well as your own. You must have the courage to act, for only by actions can goals, desires and beliefs be translated into realities. Touch a thistle timidly, and it pricks you; grasp it boldly and its spines crumble. We often think of courage in terms of heroic deeds on the battlefield, in a shipwreck, or similar crisis. I tell such people: "Study the situation thoroughly, go over in your imagination the various courses of action possible to you and the consequences which can and may follow from each course. If we wait until we are i absolutely certain and sure before we act we will never do anything. You must daily have the courage to risk making mistakes, risk failure, risk being humiliated. My own theory is that this universal "urge" is an instinct, which, when used correctly, urges us to bet on ourselves, to take a chance on our own creative potentialities. It is also my theory that people who frustrate this natural instinct, by refusing to live creatively and act with courage, are the people who develop "gambling fever" and become addicts of gam- bling tables. And the man who will not act with courage sometimes seeks the feeling of courage from a bottle. Faith and courage are natural human instincts and we feel a need to express them—in one way or an- other. Prescription: Be willing to make a few mistakes, to suf- fer a little pain to get what you want. In fact, many potential heroes, both men and women, live out their lives in self-doubt. If they only knew they had these deep resources, it would help give them the self-reliance to meet most problems, even a big crisis. Another helpful suggestion is to practice acting boldly and with courage in regard to "little things. Daily living also requires courage—and by practicing courage in little things, we develop the power and talent to act coura- geously in more important matters. They respect the dignity of human personality and deal with other people as if they were human beings, rather than as pawns in their own game. They recognize that every person is a child of God and is a unique individuality which deserves some dignity and respect. It is -a psychologic fact that our feelings about ourselves tend to correspond to our feelings about other people. When a person begins to feel more charitably about others, he invariably begins to feel more charitably to- ward himself. The person who feels that "people are not very important" cannot have very much deep-down self- respect and self-regard—for he himself is "people" and with what judgment he considers others, he himself is un- wittingly judged in his own mind. You will develop a better and more adequate self- image when you begin to feel that other people are more worthy. Another reason that Charity toward other people is symptomatic of the successful personality is because it means that the person is dealing with reality. People cannot for long be treated like ani- ; mals or machines, or as pawns to secure personal ends. So will other tyrants wherever they may be found—in the home, in business, or in individ- ual relationships. Prescription: The prescription for charity is three-fold: (1) Try to develop a genuine appreciation for people by realizing the truth about them; they are children of God, unique personalities, creative beings. A friend of mine kids his wife by telling her, whenever she asks him, "Do you love me? Jeal- ousy, for example, which is the scourge of many a mar- riage, is nearly always caused by self-doubt. The housewife who felt that a face lift might cause her husband and children to appreciate her more, really needed to appreciate herself more. Middle-age, plus a few wrinkles and a few grey hairs had caused her to lose self- esteem. Prescription: Stop carrying around a mental picture of yourself as a defeated, worthless person. This appreciation of your own worth is not egotism unless you assume that you made yourself and should take some of the credit. Practice treating other people as if they had some value—and surprisingly enough your own self-esteem will go up. When you come to this realization, however, you must necessarily conclude that all other people are to be appre- ciated for the same reason.

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One of the keys to gaining more energy in your body is to assume a more energetic posture cefixime 200mg for sale. You will probably notice that when you have low energy levels cefixime 200 mg cheap, you tend to hold your body in a tight posture with your head slightly down and shoulders slouched buy 200 mg cefixime. When you find yourself in this position, just start breathing with your diaphragm and pull your head up by imagining a cord affixed to the top of your head gently pulling your spine and neck straight and into alignment. By becoming aware of your breathing and your posture, you may notice a great deal of muscular tension or stress in certain areas of your body. That is where the next phase of physical care of the body comes into play—bodywork. In other countries around the world, bodywork practitioners are relied upon much more than in the United States. However, there is a growing trend among Americans toward increased popularity of bodywork treatments. There are many different types of bodywork to choose from, including various massage techniques, chiropractic spinal adjustment and manipulation, Rolfing, reflexology, shiatsu, and many more. Fortunately, all of these techniques can provide benefits, so it is really a matter of personal preference. Find a technique or practitioner that you really like and incorporate bodywork into your routine. Both of this book’s authors are fortunate to have experienced a broad range of bodywork, from Rolfing and deep tissue massage (often referred to as sports massage) to more gentle techniques such as Trager massage, Feldenkrais, and craniosacral therapy. Our experience has led us to the conclusion that the therapist is more critical to the outcome than the technique. If your physical body (as well as your attitude) is in need of a tune-up, begin looking for a good chiropractor or body worker. Our own personal belief is that the most effective techniques are those that teach body awareness and address underlying structural problems. We have divided these techniques into two major classifications: deep tissue work and light touch therapies. The techniques we discuss below require a practitioner to undertake extensive education and training before calling himself or herself a certified therapist. Deep tissue work such as Rolfing and Hellerwork are probably the most powerful bodywork techniques, able to quickly create change in body posture and energy levels. Unlike massage and spinal adjustment, Rolfing and Hellerwork are focused not on the muscles and spine but rather on the fascia, the network of elastic sheathing that helps support the body, keeping bones, muscles, and organs in place. According to Rolfers and Hellerwork practitioners, the fascia can be damaged by physical injury, emotional trauma, and bad postural habits, throwing the body out of alignment. Rolfing, Hellerwork, and other deep tissue treatments attempt to bring the body back into balance, restore efficiency of movement, and increase mobility by stretching and lengthening the fascia to bring it back it to its natural form and pliability. Rolfing or Hellerwork treatments consist of 10 or 11 sessions, each lasting between 60 and 90 minutes. Treatments are sequential, beginning with more superficial treatments and ending with deeper massage. Deep tissue therapies can be quite remarkable in their ability to improve breathing, posture, tolerance of stress, and energy levels. In addition, many people going through deep tissue therapy report resolution of emotional conflicts. It seems that many painful or traumatic experiences are stored in the fascia and muscles as tension. Releasing the tension and restoring freedom in the fascia can produce remarkable increases in energy levels. If Rolfing or Hellerwork is too painful for you, there are three light touch therapies that can produce similar but more gradual results and feel incredibly pleasurable. According to Trager, we all develop mental and physical patterns that may limit our movements or contribute to fatigue as well as pain and tension. During a typical session, the practitioner gently and rhythmically rocks, cradles, and moves the client’s body so as to encourage the client to see that freedom of movement and relaxation are entirely possible. The aim of the treatment is not so much to massage or manipulate, but rather to promote feelings of lightness, freedom, and well-being. Called Mentastics, these simple, dance-like movements are designed to help clients maintain and enhance the feelings of flexibility and freedom they may have experienced during the sessions. The other “light touch” therapies that we recommend are two similar techniques: Alexander and Feldenkrais. In these methods the practitioner guides the patient to become aware of habitual and limited movement patterns and replace them with more optimal movements. The participant learns the difference between muscular tension and relaxation, and how different postures feel—restricted or free. Final Comments Supplementary measures can make a dramatic impact on a person’s quality of health and quality of life. In some cases a supplementary measure is a primary therapy; in other situations it may be simply supporting or promoting good health. We highly recommend incorporating nutritional supplementation and physical care as essential supplementary measures to support or attain good health. A cellular approach to health reflects the recognition that the external and internal environment of a cell and its membrane composition, communication and signaling pathways, enzymatic activity, and cellular energy production all affect the function of that cell and, in turn, the human body’s tissues and organs. A basic cellular approach to health involves supplying both nutrients essential to cellular function and key protective antioxidants to protect cellular structures from being damaged by high blood sugar levels, toxins, and inflammation. This chapter will discuss in more detail their effects on basic cellular function. Homeostasis and Cell Membranes One of the basic functions of a cell is to create homeostasis—the ability to maintain a constant and steady internal environment. The cell accomplishes this goal by constantly adjusting its physiological processes, much the way a thermostat in a house will turn the heat or air-conditioning on and off. Every organism on the planet, from the simplest single-celled amoeba to the human being, relies on cellular homeostasis to sustain life. The first step in achieving a constant internal environment is creating a healthy cell membrane— the wall between the internal cell and its external environment. Without a healthy membrane, cells lose their ability to hold water, vital nutrients, and electrolytes. They also lose their ability to communicate with other cells and be controlled by regulating hormones. An alteration in cell membrane function can result in cell injury and death, which contribute to a number of chronic diseases. As a result, the composition of cell membranes and the resulting structure, function, and integrity can be influenced by dietary changes. A diet high in saturated fat (mostly from animal fats) and trans-fatty acids produces cell membranes that are much less fluid in nature than the membranes of people who eat optimal levels of monounsaturated fats (from nuts, seeds, and olive oil) and essential fatty acids, especially the omega-3 fatty acids. Cell membranes also act as a “pool” from which fatty acids are transformed into hormone-like compounds called eicosanoids. These compounds are responsible for regulating a wide variety of cellular processes, including inflammation, platelet aggregation, and constriction and dilation of blood vessels, as well as cardiovascular, digestive, and kidney function. Changing the type or ratio of dietary fat can produce significant changes in physiology. For example, a higher ratio of omega-3 to omega-6 fatty acids in cell membranes leads to a greater production of anti-inflammatory and brain- protective compounds known as resolvins and protectins. For example, long-chain omega-3 fatty acids and monounsaturated fats appear to improve the response to the hormone insulin, while saturated fats, trans-fatty acids, and too much cholesterol in cell membranes have the opposite effect. This system pumps three sodium ions out of the cell for every two potassium ions that it pumps in. In doing so, it helps maintain three important cell characteristics—resting electrical potential, pH, and cellular volume. It also plays a role in many more cellular functions, including cell communication, antioxidant protection, and regulation of other important cellular ions such as calcium. For nerve cells, it is even more critical, and is responsible for nearly 70% of the nerve cell’s energy expenditure. Obviously, impairment of the sodium-potassium pump is severely detrimental to the health of the cell. For example, an elevation in blood sugar (hyperglycemia, as occurs in diabetes or after a large intake of high-sugar foods) is known to induce the production of inflammatory proteins, increase oxidative damage, and lead to the binding of glucose to cellular proteins (glycosylation), and any one of these potential mechanisms can lead to damage of the sodium-potassium pump. Other ways the pump can be damaged include oxidative damage and lack of oxygen (hypoxia).

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