By H. Gamal. Saint Ambrose University. 2018.
Whether such gamma bursts also occur during motor imagery remains to be shown in ongoing research work pristiq 50mg generic. Animal studies pristiq 50mg mastercard, focused on multiple-unit neuronal activity (the ﬁring of groups of neurons) to perform two- and three-dimensional cursor control purchase pristiq 100mg without prescription, are of special value for the realization of a multidimensional human BCI buy pristiq 100mg otc. The feasibility of direct cursor control for the selection of icons or letters using an implanted neurotropic cortical electrode was already dem- onstrated by Kennedy et al. This research was partially supported by FWF and AUVA in Austria, DFG in Germany, and NIH in the United States. It is considered to be based on central processes, which are responsible for the maximally efﬁcient organization of motor performance. A strong argument in favor of such an efﬁciency hypothesis of preparatory processes is the fact that providing prior information about movement parameters or removing time uncer- tainty about when to move signiﬁcantly shortens reaction time. In this chapter, I will brieﬂy summarize the behavioral effects of prior information and then describe some underlying neuronal correlates encountered in motor cortical areas of behaving 0-8493-1287-6/05/$0. The types of changes in neuronal activity and their selectivity during preparation will be portrayed and compared with other cortical areas that are involved in motor behavior. Furthermore, by linking motor cortical activity directly to behav- ioral performance, the trial-by-trial correlation between single neuron ﬁring rate and reaction time revealed strong task-related cortical dynamics. Finally, the cooperative interplay among neurons, expressed by precise synchronization of their action poten- tials, will be illustrated and compared with changes in the ﬁring rate of the same neurons. New concepts, including the notion of coordinated ensemble activity, and their functional implication during movement preparation will be discussed. To adjust appropriately, the motor system has to assess the context in which it acts, including the properties of objects in the surrounding world and the prevailing environmental conditions. Since we often face problems that need to be solved immediately, the most essential processes underlying interactive behavior and performed in an interactive way include attention, intention, estimation of temporal and spatial constraints, anticipation, motivation, judgment, decision-making, and movement preparation. To perform all these processes, the brain continuously needs to monitor the external world, read out important information, input the desired information, retrieve related information from memory, manipulate and integrate all types of information, select the appropriate (motor) response, and then output the information necessary for initiating the response to particular brain areas. It is also needed to suppress unnecessary output to inappropriate brain areas and to inhibit inappropriate actions in order to perform spatially and temporally coordinated actions. It would be too long-winded to go into the details of all these processes and the related concepts here. For instance, many conceptual discussions about the linkage between attention, intention, and preparation within the framework of infor- mation processing operations are presented in the literature. One of the most fascinating processes involved in motor behavior is movement preparation. It is based on central processes responsible for the maximally efﬁcient organization of motor performance. In order for motor performance to be efﬁciently organized, both contextual and sensory information have to be assembled and integrated to shape the motor output. The notion of uncertainty, which is related to the manipulation of contextual information, is at the core of preparatory processes. The best-suited paradigm for studying such processes is the so-called “preparation paradigm. This picture, modiﬁed after the seminal anatomical work of Korbinian Brodmann, which appeared in 1909,5 shows, among others, the location of the primary motor cortex, area 4 (ﬁlled circles), just in front of the central sulcus (the curved line between numbers 4 and 1) and the premotor cortex (area 6, empty circles). Furthermore, posterior to the central sulcus, the somatosensory cortex is located (areas 1 and 2, stripes) as well as parietal area 5 (triangles). Neuronal activity presented in this chapter was mainly recorded in the primary motor cortex and the dorsal premotor cortex. By means of such prior information, the context in which the subject is placed can be experimentally manipulated. The subject knows with more or less precision both what to do and when to initiate the requested movement, and has to adjust movement preparation accordingly. Requin and colleagues4 reviewed the topic of movement preparation in great detail. The focus here will be restricted to a description of the neuronal correlates of movement preparation obtained mainly in motor cortical areas such as the hand areas of the primary motor cortex and the dorsal premotor cortex (Figure 8.
It will enhance the effect of any other cen- mans in the same way that it affects rodents discount pristiq 50mg with amex. People operating consistent anti-inflammatory buy pristiq 100 mg without prescription, anti-fungal cheap pristiq 50 mg, anti-stress generic 100 mg pristiq overnight delivery, and heavy equipment or working in situations that require a sedative effects. In one well-known study, extracts of high level of alertness should keep this in mind when ashwaganda root were shown to significantly increase using ashwaganda. Side effects Experimenters have had mixed results in demon- strating anti-tumor and anti-cancer properties of ashwa- No undesirable side effects have been reported with ganda. GALE ENCYCLOPEDIA OF ALTERNATIVE MEDICINE 2 135 OTHER KEY TERMS “Withania somnifera aphrodisiaca. Decoction—A liquid extract of a herb, made by simmering or boiling the herb in water, then straining out the plant parts. Poultice—A soft moist mass of cloth, usually con- Asthma taining herbs, applied warm or hot to relieve pain or speed healing in a part of the body. Definition Psoriasis—A skin disease characterized by dry, Asthma is a chronic inflammatory disease of the air- scaling, whitish patches. This inflammation periodically causes Scabies—A contagious skin disease caused by a the airways to narrow, producing wheezing and breath- mite and characterized by small, raised, red, very lessness sometimes to the point where the patient gasps itchy pinprick bumps on the skin. This obstruction of the air flow either stops spon- Tincture—An alcohol-based extract of a herb pre- taneously or responds to a wide range of treatments. Description Vegan—Food products made without any animal Between 16 and 17 million Americans have asthma products such as meat, milk, or eggs. Blacks, Hispanics, American Indians, and Alaskan na- tives had higher rates of asthma-control problems than whites or Asians in the United States. Interactions The changes that take place in the lungs of asthmat- ics make their airways (the bronchi and the smaller bron- There are few, studies of how ashwaganda interacts chioles) hyper-reactive to many different types of stimuli with traditional Western medicines. In an asthma attack, the many years in combination with other Ayurvedic herbs muscle tissue in the walls of the bronchi go into spasm, without incident. Ayurvedic practitioners believe that and the cells that line the airways swell and secrete when ashwaganda is combined with other herbs in reju- mucus into the air spaces. Both these actions cause the venation formulas, it enhances the effects of these other bronchi to narrow, a change that is called bronchocon- herbs. Resources Cells in the bronchial walls, called mast cells, release BOOKS certain substances that cause the bronchial muscle to con- Chevallier, Andrew. The American Pharmaceutical Association leukotrienes, also bring white blood cells into the area. New York: William Many patients with asthma are prone to react to substances Morrow and Company, 1999. Many people with asthma do not realize that aller- ORGANIZATIONS gens are triggering their attacks. While the symp- 136 GALE ENCYCLOPEDIA OF ALTERNATIVE MEDICINE 2 toms may be similar, certain important aspects of asthma are different in children and adults. When asthma begins INHALED ALLERGENS in childhood, it often does so in a child who is likely, for MOST OFTEN TRIGGERING ASTHMA ATTACKS genetic reasons, to become sensitized to common aller- gens in the environment. In 2004, scientists in Helsinki, Finland, Animal dander identified two new genes that cause atopic asthma. The discovery might lead to earlier prediction of asthma in Cockroach allergens children and adults. When these children are exposed to Dust mites dust, animal proteins, fungi, or other potential allergens, Indoor fungi (molds) they produce a type of antibody that is intended to engulf and destroy the foreign materials. This has the effect of Occupational allergens such as chemicals, fumes, particles of industrial materials making the airway cells sensitive to particular materials. This condition of atopy is present in at least one third and as many as one half of the general population. When an infant or young child wheezes during viral in- • cockroach allergens fections, the presence of allergy (in the child or a close • pollen relative) is a clue that asthma may well continue throughout childhood. Many adults who are • air pollutants not allergic have such conditions as sinusitis or nasal In addition, there are three important factors that polyps, or they may be sensitive to aspirin and related regularly produce attacks in certain asthmatic patients, drugs.
A number of infections caused by Chlamydia tra- Signiﬁcant drug–drug interactions are those that po- chomatis purchase pristiq 50mg amex, such as trachoma generic pristiq 100mg overnight delivery, inclusion conjunctivitis discount pristiq 50mg on line, tentiate the effects of other agents and require dosage pneumonia cheap pristiq 100mg, and urethritis, can be treated with topical or modiﬁcation. These include certain anticoagulants, hy- systemic sulfonamides, although tetracycline or erythro- poglycemic sulfonylureas, and hydantoin anticonvul- mycin is preferred. Sulfonamides, such as sulfadiazine, in combination with pyrimethamine, are considered the treatment of choice of symptomatic toxoplasmosis. Patients should be TRIMETHOPRIM well hydrated to prevent crystalluria; this problem may be reduced with the use of triple sulfas (trisulfapyrimi- Chemistry, Structure, and Mechanism dine). Some regimens have included a sulfonamide (sul- of Action fadoxine) in combination with pyrimethamine (Fansidar) for the treatment of chloroquine-resistant malaria caused Trimethoprim (Trimpex, Proloprim) is a structural ana- by P. It dif- Topically active sulfonamides are useful in prevent- fers from the sulfonamides in that it acts at a second ing infections in burn patients. Mafenide acetate step in the folic acid synthetic pathway; that is, it 518 VI CHEMOTHERAPY competitively inhibits dihydrofolate reductase. This is Peak drug levels in plasma are achieved in 1 to 4 hours the enzyme that catalyzes the reduction of dihydrofolic following oral administration and 1 to 1. At this time, the TMP-SMX plasma ratio is Dihydrofolate reductase is present in both mammalian 1:20, which is the ratio most effective for producing a tissue and bacteria, but 20,000 to 60,000 times more synergistic effect against most susceptible pathogens. Tri- bind to plasma protein (45 and 66% respectively) and methoprim was added to sulfamethoxazole to synergisti- both are metabolized in the liver. Approximately 40 to cally and sequentially inhibit bacterial synthesis of 60% of both parent drugs and their metabolites is ex- tetrahydrofolic acid. The combination was also designed to creted by the kidney within 24 hours; in moderate to se- delay development of bacterial resistance. Sulfameth- vere renal dysfunction the dose should be reduced by oxazole was selected in part because it is a congener of the approximately one-half. Only the parent compounds frequently used sulﬁsoxazole but exhibits slower enteric are excreted in the bile. Clinical Use of Antibacterial Spectrum and Resistance Trimethoprim–Sulfamethoxazole Trimethoprim exhibits broad-spectrum activity. It is most TMP-SMX (Septra, Bactrim) is used in the treatment of commonly used in combination with sulfamethoxazole genitourinary, GI, and respiratory tract infections and is active against most gram-positive and gram- caused by susceptible bacteria. Trimethoprim is present in vaginal secretions in Resistance can develop from alterations in dihydro- high enough levels to be active against many of the or- folate reductase, bacterial impermeability to the drug, ganisms found in the introital area that are often re- and by overproduction of the dihydrofolate reductase. In some patients with re- The most important mechanism of bacterial resistance current UTIs, most notably women of childbearing age, to trimethoprim clinically is the production of plasmid- the long-term use of one tablet taken at night is an ef- encoded trimethoprim-resistant forms of dihydrofolate fective form of chemoprophylaxis. Food and Drug Administration Because trimethoprim and sulfamethoxazole have (FDA) for treating UTIs in both children and adults. The combination ance to the combination is less than that observed when is also effective for covering the carrier state of the drugs are used individually. Resistance is an in- Salmonella typhi, the agent of typhoid fever, and other creasing problem in a number of bacteria, but is espe- Salmonella spp.. Trimethoprim is well absorbed from the GI tract, and Because trimethoprim accumulates in the prostate, peak blood levels are achieved in about 2 hours. Tissue TMP-SMX is used to treat prostatitis caused by sensi- levels often exceed those of plasma, and the urine con- tive organisms. Therapy can be prolonged (4–6 weeks) centration of trimethoprim may be 100 times that of the and repeat courses of therapy may be necessary. Trimethoprim readily enters the CSF if inﬂam- Trimethoprim alone, because of its lipid solubility, can mation is present. The half-life of the drug is approxi- be effectively used when patients exhibit an allergic re- mately 11 hours. Recently a second target, unique to the ﬂuoro- TMP-SMX remains the antimicrobial therapy of quinolones, has been identiﬁed as topoisomerase type choice in both the treatment and prevention of infec- IV. In those with AIDS, treatment is belong to the general class of DNA enzymes called more prolonged and relapse is common. The effect of quinolones on these are at increased risk for untoward effects such as fever, DNA enzymes is initially bacteriostatic but becomes hepatitis, rash, and leukopenia. These drug targets may be primary or Adverse Effects and Drug Interactions secondary depending upon the organism; this observa- tion can affect the bacterial potential for the develop- Serious adverse effects are rare except in AIDS patients. Each generation and skin rashes are particularly common in patients with (ﬁrst through fourth) has spectrum speciﬁcity and AIDS.
The child can have an inguinal hernia that tures buy pristiq 100 mg low cost, chromosome analysis cheap pristiq 50 mg with amex, hormone levels order 100 mg pristiq, and analy- upon repair is found to contain testicles purchase 50 mg pristiq amex. Chromosome analysis reveals normal male chro- Affected individuals have a short, blind ending vagina mosomes. Affected individuals can have elevated and no uterus, cervix, fallopian tubes, or ovaries. During luteinizing hormone, normal to slightly elevated testos- puberty, some girls will have absent or decreased sexual terone, and high estradiol for men. Breasts develop normally and can be large in size hormone may also be normal to elevated. People with androgen receptor function in skin fibroblast cells is also CAIS are usually raised as females and have normal used to aid in a diagnosis. All women with CAIS are ster- As of 2001, direct genetic testing for molecular ile. In families with CAIS, all affected members will have defects in the androgen receptor gene is being done on a complete androgen insensitivity and similar physical research basis only. Partial androgen insensitivity syndrome Treatment and management Children with PAIS usually present at birth due to Complete androgen insensitivity ambiguous genitalia. The genitalia can look like female genitals with some masculinization, completely Treatment of CAIS requires the removal of the testi- ambiguous genitals where the sex of the baby cannot be cles from the pelvis or inguinal canal to decrease risk of immediately determined, or male genitals with some testicular malignancy. The degree of severity is a direct result of nancy is approximately 5% and rarely occurs before age the degree of severity of the genetic alteration in the 25, the testicles are usually removed after the develop- androgen receptor and resulting amount of functional ment of the secondary sex characteristics, as the testes androgen receptor. After the removal of the same as CAIS, with absent fallopian tubes, cervix, the testes, estrogen supplementation is started to aid in GALE ENCYCLOPEDIA OF GENETIC DISORDERS 85 the development of secondary sex characteristics and to Intersex Society of North America. Reconstructive sur- Carin Lea Beltz, MS, CGC gery of the genitals and lengthening of the vagina may be necessary. People with PAIS raised as boys may need surgery to improve the appearance of the genitals. Androgen sup- plementation may be implemented, though long-term IAnemia, sideroblastic affects of androgen therapy are not known. Definition X-linked sideroblastic anemia is a hereditary Mild androgen insensitivity enzyme disorder in which the body has adequate iron but Males with MAIS may require no treatment at all or is unable to incorporate it into hemoglobin. Males who are infertile may benefit from assisted reproductive tech- Description nologies. X-linked sideroblastic anemia is the hereditary form of sideroblastic anemia, also known as iron overload ane- Prognosis mia or sideroblastosis. Another, more common type of sideroblastic anemia is called acquired sideroblastic For CAIS and MAIS, the prognosis is excellent. Generally, gender assignment is not difficult and sexual orientation is female for CAIS and male for MAIS. In sideroblastic anemia, iron enters a developing red Treatment usually involves minimal surgery and hor- blood cell and is not incorporated properly into the hemo- mone supplementation. This causes prognosis is very dependent upon the severity of the con- iron to accumulate in the mitochondria and sideroblasts. Assignment of gender can be difficult and genital The defective hemoglobin then transports oxygen poorly, surgery can be more involved. Sideroblastic anemia is often mistaken for iron defi- ciency anemia, but tests usually reveal normal or Resources increased levels of iron. The pri- PERIODICALS mary type of inherited sideroblastic anemia was first Warne, G. He identified of the molecular genetics and the internet: A point of cases of X-linked sideroblastic anemia in two brothers view. The genetic abnormality that causes ORGANIZATIONS X-linked sideroblastic anemia was identified almost 40 AIS Support Group (AISSG). KEY TERMS Other inherited forms of sideroblastic anemia Heme—The iron-containing molecule in hemo- globin that serves as the site for oxygen binding. A rare autosomal recessive form Hemochromatosis—Accumulation of large of inherited sideroblastic anemia occurs in both males amounts of iron in the tissues of the body. Autosomal dominant Hemoglobin—Protein-iron compound in the inheritance has also been reported.
The commonly used decision support techniques in medical decision support systems are intelligent agents discount 50 mg pristiq otc, rule- based engines generic pristiq 50mg line, heuristics buy 100mg pristiq with amex, and decision algorithms 100mg pristiq sale. The use of an intelligent agent or softbot (intelligent software robot) is a popular decision support technique that has the potential to become one of the most important in the next decade (Turban & Aronson, 2000). There are several definitions of an intelligent agent, but the general concept is that the agent carries out a set of operations with some degree of autonomy (Murch & Johnson, 1999). The key characteristics of an intelligent agent are that it should be autonomous, goal-oriented, collaborative, and flexible (Brenner, Zarnekow, & Wittig, 1998). A heuristic is a rule of thumb that is used primarily to arrive at a “good enough” solution to a complex problem. When the problem or the reality is extremely complex and optimization techniques are not available, a heuristic may be used. Heuristics do not yield definitive solutions, but assist decision makers in arriving at provisional solutions (Camms & Evans, 1996). For example, the determination of the choice of initial doses of both medication and dialysis treatment for a renal patient relies on population-based pharma- cokinetic and solute kinetic heuristics, respectively. Rule-based decision support systems primarily store knowledge in the form of rules and problem solving procedures. Rules are applied on the data collected using an inference engine, decisions are suggested, and explanations supplied (Turban & Aronson, 2000). For example, DARWIN, a renal decision support system, uses rule-based reasoning to advise dialysis technical staff regarding the response to bacteriologic monitoring of fluids used during hemodialysis. Another example of a rule-based or expert system is the use of clinical protocols to generate suggestions regarding anemia treatment using erythropoietin and iron protocols. On the basis of knowledge of new and historical laboratory results and medications, the expert system can suggest the modification of drug doses or the discontinuation of a medication. The inference engine can also provide an explanation of the basis of the recommendation in the protocol. A decision algorithm is a set of instructions that is repeated to solve a problem. Highly intelligent algorithms include the capability to learn and to perform several iterations of the algorithm or of parts of the algorithm until an optimal solution is reached (Turban & Copyright © 2005, Idea Group Inc. Copying or distributing in print or electronic forms without written permission of Idea Group Inc. A very simple decision algorithm may alert physicians on receipt of out- of-range laboratory results. In the next sections, we will discuss about the characteristics of a medical decision support systems, generic components, problem areas in which decision support systems are used and knowledge sharing standards. Characteristics of M edical Decision Support Systems To understand the characteristics of a medical decision support system, it is important to analyze the medical decision making process. A clear understanding of the medical decision making process is essential to appreciate the value and the characteristics of a medical decision support system. It is an extremely complex sequence of inter related and differentiated activities that occur over a period of time. The vastness of the knowledge area presents itself infinite paths to reach a decision. Thus, the importance of finding an optimal path is extremely important in the decision making process. Any assistance in this critical step can be of immense value to the medical decision makers. The second is the beliefs and opinions about the objective states, and the processes including input and outcomes states. The third is the values and consequences attached to each outcome of the event-choice-action combination. The decision support literature classifies problems into three major categories: struc- tured, semi-structured, and unstructured (Gorry & Morton, 1971).