By C. Emet. Massachusetts College of Liberal Arts. 2018.
Spina bifida appears as a localized mass on the back covered by skin or by the meninges buy avanafil 100mg with amex, the three-layered membrane that envelops the spinal cord purchase 100mg avanafil with visa. Anencephaly is a lethal birth defect characterized by absence of all or part of the skull and scalp and malformation of the brain generic 200mg avanafil with amex. Encephaloceles are rare and are characterized by protrusion of brain tissue and membranes through the skull buy avanafil 200 mg visa. Hydrocephaly develops in most the highest prevalence (about one in 100 pregnancies) infants either before or after surgical repair of the spine exists in certain northern provinces in China; an interme- defect discount avanafil 100mg online. Most infants with anencephaly nancies) has been found in the Scandinavian countries. In are stillborn, or die within the initial days or weeks after the United States, the highest prevalence has occurred in birth. Worldwide there has been a steady down- Infants with encephaloceles have variable neurologic ward trend in prevalence rates over the past 50-70 years. When only the brain covering is involved, the indi- Signs and symptoms vidual may escape any adverse effect. However, when the brain is involved in the defect, impairments of the special Because of the faulty development of the spinal cord senses such as sight, hearing, and cognitive thinking and nerves, a number of consequences are commonly commonly result. As a rule, the nerves below the level of the defect develop in a faulty manner and fail to func- Diagnosis tion, resulting in paralysis and loss of sensation below the level of the spinal lesion. Since most defects occur in the At birth, the diagnosis is usually obvious based on lumbar region, the lower limbs are usually paralyzed and external findings. Furthermore, the bowel and blad- ultrasound examination after 12-14 weeks of pregnancy. Open neural tube defects leak this fetal chemical ability whether surgical correction is performed or not. Surgery closes the defect, providing protection Disabilities Research Reviews 4, no. A common complication ORGANIZATIONS that may occur before or after surgical correction is the March of Dimes Birth Defects Foundation. Atlanta, GA (770) spinal fluid from the ventricles to drain into the circula- 488-3550. International Shrine surgical procedures have been used to protect the urinary Headquarters, 2900 Rocky Point Dr. Stevenson, MD It has been found that 400 micrograms of folic acid taken during the periconceptional period (two to three months prior to conception, and two to three months fol- lowing conceptions) protects against most neural tube defects. While there are a number of foods (green leafy vegetables, legumes, liver, and orange juice) that are INeuraminidase deficiency good sources of natural folic acid, synthetic folic acid is Definition available in over-the-counter multivitamins and a number of fully-fortified breakfast cereals. Neuraminidase deficiency, or sialidosis, is a rare inherited metabolic disorder with multiple symptoms that Additionally, a population-wide increase in folic can include skeletal abnormalities and progressive neuro- acid intake has been achieved through the fortification of logical degeneration. The increased blood folic acid levels Description achieved in recent years has likely resulted from the syn- Nomenclature ergy of dietary, supplementation, and fortification sources of folic acid. Neuraminidase deficiency is caused by a mutation, or change, in the NEU1 gene that codes for the lysoso- mal enzyme alpha-N-acetylneuraminidase, or neu- Prognosis raminidase for short. This enzyme sometimes is referred Infants with anencephaly are usually stillborn or die to as sialidase. Sialidosis type II is the more severe form of 802 GALE ENCYCLOPEDIA OF GENETIC DISORDERS neuraminidase deficiency, with symptoms developing in Neuraminidase the fetus, at birth, or during infancy or early childhood. Neuraminidase, or sialidase, is a type of enzyme known as an exoglycosidase because it cleaves terminal Over the years, this disorder has been called by a sugar units, or residues, off oligosaccharides. Specifi- number of different names, in addition to neuraminidase cally, neuraminidase cleaves, or hydrolyzes, terminal deficiency, alpha-neuraminidase deficiency, sialidase sialic acid residues. It sometimes is known as neuraminic acid, is a type of sugar molecule that often is cherry-red spot and myoclonus syndrome, cherry-red at an end of an oligosaccharide. The oligosaccharides spot myoclonus epilepsy syndrome, or myoclonus and with sialic acid residues may be attached to proteins (gly- cherry-red spot syndrome, in reference to characteristic coproteins). Other names include glyco- vents the proper breakdown of oligosaccharides and protein neuraminidase deficiency, NEUG deficiency, glycoproteins that contain sialic acid and the disorder is NEU or NEU1 deficiency, and neuraminidase 1 defi- ciency. Sialidosis type I sometimes is referred to as juve- characterized by the accumulation and excretion of these nile sialidosis and type II as infantile sialidosis, in substances. In addition to interfering with the lysosomal break- down of sialic acid compounds, neuraminidase defi- Lysosomal storage diseases ciency can lead to abnormal proteins. Following protein Lysosomes are membrane-bound spherical compart- synthesis, some lysosomal enzymes reach the lysosome ments or vesicles within the cytosol, the semi-fluid areas in an inactive form and require further processing for of cells.
We initially focused on well-learned tasks rather than on the process of learning such tasks generic avanafil 200 mg with amex. This was largely a pragmatic approach to the question of how stable neural states are represented in the brain best 50 mg avanafil. The robotic device also appears to be well suited for exploring the role of afferent feedback in motor control purchase avanafil 200 mg overnight delivery. It is known that there is a rough correspondence between sensory and motor representations in M1 discount avanafil 200mg on line. The making of movements at an angle from a stimulus direction: studies of motor cortical activity at the single cell and population levels generic avanafil 200mg visa, Exp. It is now established that 10-, 20-, and 40-Hz motor cortical oscillations are associated with constant, sustained muscle contractions, again a static condition. Sigma band oscillations of about 14 Hz may be indicative of maintained active suppression of a motor response. The dynamic phase at the onset of an intended movement is preceded by a marked drop in oscillatory power, but not all frequencies are suppressed. Moreover, there is increasing evidence that oscilla- tory potentials, even of low frequencies (4–12 Hz), may be linked to dynamic episodes of movement. Most surprisingly, the 8-Hz cortical oscillation — the neurogenic component of physiological tremor — is emerging as a major factor in shaping the pulsatile dynamic microstructure of movement, and possibly in coordinating diverse actions performed together. Based on a thorough study of rabbit cortical activity, Kornmüller postulated that alpha rhythms dominate in granular cortex, and beta rhythms in agranular cortex. Extracellular ﬁeld potentials are generated by neuronal dipoles created within elongated dendritic ﬁelds, aligned in parallel arrays. Cortical pyramidal cells with their long apical dendrites are the classic example of dipole generators. The current sink is the site of net depolarization, and the source is the site of normal membrane polarity or of hyperpolarization. Many cortical neurons have pacemaker-like membrane properties such that they can produce oscillatory potentials at a variety of frequencies; generally, the higher the depolarization, the faster the frequency. Inevitably such circuits involve inhibitory interneurons to reinforce the excitation–inhibition alternation. Linked oscillators, with close to the same frequency, invariably synchronize over time. Therefore, oscillations offer a useful strategy for circumventing, or at least offsetting, conduction delays within the nervous system, but the price to pay is a preparatory, oscillatory lead-up time. Brain rhythms can be monitored with noninvasive EEG or magnetoencephalo- graphic (MEG) recording, electrocorticograms (ECoG) recorded with subdural grids of electrodes placed on the surface of the brain, or local ﬁeld potentials (LFPs) recorded with microwires or microelectrodes within the brain tissue. They can also be seen in the ﬁring patterns of single neurons, but not as clearly and reliably. In sensorimotor cortex, mu and beta rhythms, which may be prominent prior to a movement, are commonly suppressed at the onset of a movement. These changes in oscillatory potentials are time-locked to the event, but unlike event-related poten- tials, they are not usually phase-locked to the event. Such phenom- ena are manifested as frequency-speciﬁc changes of the ongoing electromagnetic Copyright © 2005 CRC Press LLC activity of the brain. A decrease in power in a given frequency band is thought to be due to a decrease in synchrony of the underlying neuronal population, and therefore is commonly termed an event-related desynchronization (ERD). Con- versely an increase in power in a frequency band is termed an event-related syn- chronization (ERS) of the neuronal population. Because of the well-established ERD of both mu and beta rhythms at the time of movement onset, and their reappearance when movement stops, they are commonly equated with “inhibition” or “deactivation” of the motor cortex. Even if the inhibitory duty cycle is more than 50%, there is a regular period of depolarization following the inhibition. Neglecting this dichotomy can severely limit the usefulness of many ideas about the function of rhythms in sensorimotor cortex. The appearance of a strong LFP oscillation in a cortical area does have an inﬂuence on trains of action potentials.
Intake of fresh • being HIV positive grape juice buy avanafil 200mg fast delivery, preferably made from from dark grapes order avanafil 50 mg online, on a • a history of steroid drug use or drug abuse daily basis at a time other than mealtime has also been found to be helpful trusted 50 mg avanafil. Minor backaches may be relieved • development of an obvious structural deformity with the application of a heating paste of ginger(Zingiber • a history of rapid weight loss officinale) powder and water buy generic avanafil 200mg on line, allowed to sink in for 10 • unexplained fever 50mg avanafil overnight delivery, or nightsweats, with back pain minutes, and followed by an eucalyptus rub. Treatment A thorough differential diagnosis is important be- Homeopathy fore any treatment is considered. There are times when Homeopathic treatment for acute back pain consists alternative therapies may be most beneficial, and other of various applications of Arnica (Arnica montana); as an times when more invasive treatments are needed. Bellis perennis may be recommended forms of alternative treatment in the United States for relief for deep muscle injuries. Other remedies may be recom- of back pain caused by straining or lifting injuries, and has mended based on the symptoms presented by the patient. Some osteopathic physicians, physical thera- Body work and yoga pists, and naturopathic physicians also use spinal manipu- Massage and the numerous other body work tech- lation to treat patients with low back pain, along with work niques can be very effective in treating low back pain. Additional recommenda- Yoga, practiced regularly and done properly, can be tions of shoe orthotics, exercise, cold packs to reduce and combined with meditation or imagery to both treat and inhibit swelling immediately after injury followed one to prevent future episodes of low back pain. Nutritional supplements known to be bene- Allopathic treatment ficial to joint repair and integrity, collagen support, and All forms of treatment of low back pain are aimed wound repair may also be recommended, including glu- either at symptom relief or to prevent interference with 1236 GALE ENCYCLOPEDIA OF ALTERNATIVE MEDICINE 2 the processes of healing. None of these methods appear mended for patients whose back pain is associated with a to speed up healing. Low back pain with leg involvement Acute pain Treatment of sciatica and other disorders that in- Acute back pain is treated with muscle relaxantsor volve the legs may include NSAIDs. Patients with long- nonsteroidal anti-inflammatory drugs (NSAIDs), such as standing sciatica or spinal stenosis that do not respond to ibuprofen or aspirin. Patients tors use cortisone injections in trigger points and verte- are recommended by one source, do not worry, and to bral facet joints to relieve the pain, this form of treatment stay active. Some patients may be prescribed opiod analgesics traction and transcutaneous (through the skin) electrical (pain relievers with codeine or codeine similars), howev- nerve stimulation. The use of muscle relaxants may increase risk of further damage, but they have been Expected results shown to be more effective than placebo (though no bet- The prognosis for most patients with acute low back ter than NSAIDS alone) in relieving acute pain. About 80% of patients recover com- patient has not experienced some improvement after sev- pletely in 4–6 weeks. The prognosis for recovery from eral weeks of treatment, the doctor will reinvestigate the chronic pain depends on the underlying cause. Prevention Chronic pain Low back pain due to muscle strain can be prevent- Patients with chronic back pain are treated with a ed by lifestyle choices, including regular physical exer- combination of medications, physical therapy, and occu- cise and weight control, avoiding smoking, and learning pational or lifestyle modification. The medications given the proper techniques for lifting and moving heavy ob- are usually NSAIDs, although patients with hyperten- jects. Exercises designed to strengthen the muscles of the sion, kidney problems, or stomach ulcers are advised not lower back and the opposing abdominals are also recom- take these drugs. Simple actions can also help prevent low back than six weeks are advised to be monitored periodically pain, such as putting a small, firm cushion behind the for complications. Chronic pain, by definition longer lower back when sitting for long intervals, using a soft than three months in duration, may also prompt a more pillow for sleep that supports the lower neck without cre- thorough diagnostic workup. Resources Patients with herniated disks may be treated surgi- cally if the pain does not respond to medication. A newer surgical procedure known In Current Medical Diagnosis & Treatment 1998, edited as kyphoplasty, involving guided penetration of the back by Lawrence. Stamford, CT: Appleton & and cemented repair, may be indicated in pain due to Lange, 1998. Waikanae, New sometimes benefit from pain management techniques, Zealand: Spinal Publications New Zealand Ltd. Chiropractic—A method of treatment based on the interactions of the spine and the nervous system. Lowfat diet see Ornish diet Lumbar spine—The segment of the human spine Lumbar pain see Low back pain above the pelvis that is involved in low back pain. Radicular—Pain that is caused by compression or Lung cancer impingement at the root of a nerve. Referred pain—Pain that is experienced in one Definition part of the body but originates in another organ or Lung cancer is a disease in which the cells of the area. The pain is referred because the nerves that lung tissues grow uncontrollably and form tumors. It is supply the damaged organ enter the spine in the the leading cause of death from cancer among both men same segment as the nerves that supply the area and women in the United States. Society (ACS) estimated that in 1998, at least 172,000 Sciatica—Pain caused by irritation of the sciatic new cases of lung cancer were diagnosed, and that lung nerve.
The first one consists of five multi-layer perceptron ANNs discount 50 mg avanafil with visa, each using as input either one of the computed texture feature sets or its reduced version after GA-based feature selection discount avanafil 50 mg. The second ensemble of classifiers was generated by combining five different type primary classifiers generic 200mg avanafil visa, namely one multi-layer perceptron ANN buy 100mg avanafil, one probabilistic ANN proven avanafil 50mg, and three k-Nearest Neighbour (k-NN) classifiers. The primary classifiers of the second ensemble used identical input vectors, which resulted from the combination of the five texture feature sets, either directly or after proper GA- Copyright © 2005, Idea Group Inc. Copying or distributing in print or electronic forms without written permission of Idea Group Inc. Examples of typical CT images of liver showing different types of liver tissue: (a) normal liver tissue, (b) hepatic cyst, (c) haemangioma, and (d) hepatocellular carcinoma (a) (b) (c) (d) based feature selection. The final decision of each ensemble of classifiers was extracted by applying appropriate voting schemes across the outputs of the primary classifiers. The optimally performing CAD system architecture was chosen, based on the achieved classification performances in a testing data set. Therapeutic Decision Support TDS systems aim to optimise and individualise patient treatment, including diet, drug treatment or radiotherapy treatment. In the following, the fundamental theory for the development of TDS systems is presented along with an example of a TDS system. Copying or distributing in print or electronic forms without written permission of Idea Group Inc. Clinical Decision Support Systems 263 Basic Principles TDS systems are based on the combined use of available patient or literature data and simulation models (Figure 4). More specifically, individualised patient data (medical history, laboratory tests, medical imaging data) along with information about the disease available in databases (DBs) provide input to appropriate simulation models. Simulation is then performed for alternative therapeutic schemes leading to the estimation of an optimal therapeutic scheme for the specific patient. TDS systems can be based on the use of simulation models of biological and physiologi- cal procedures and/or stochastical analysis of available data. The most widely used methodologies include Compartmental Models (CMs), stochastical simulation methods, cellular automata methods, ANNs and AI methods (Brown & Rothery, 1993). The specific goal of CMs is to represent complicated physiological systems with relatively simple mathematical models. In compartmental analysis, systems that are continuous and essentially non-homogeneous are replaced with a series of discrete spatial regions, termed compartments, considered to be homogeneous (Jacquez, 1985). A system can be defined by a class of dynamic models widely used in quantitative studies of the kinetics of materials in physiological systems. Materials are considered to be either exogenous (such as a drug or tracer) or endogenous (such as a substrate like glucose or an enzyme or hormone like insulin). Kinetics refers to time-variant processes, such as production, distribution, transport, utilisation, and substrate-hormone control interac- tions. A compartment is an amount of material or spatial region that behaves as though it is well mixed and kinetically homogeneous. This means that any samples taken from the compartment at the same time will have identical properties and are equally representative of the system. Kinetic homogeneity means that each particle within a chamber has the same probability of taking any exit pathway. A CM then is defined as a finite number of compartments with specific interconnections between them, each representing a flux of material which physiologi- cally represents transport from one location to another and/or a chemical transformation (Cobelli & Foster, 1998). Copying or distributing in print or electronic forms without written permission of Idea Group Inc. Consequently, the ability to equate a compartment to a physical space depends on the system being studied and associated model assumptions. Stochastical models involve random variables that are functions of time and include probabilistic considerations. For a given set of initial conditions, a stochastic model yields a different solution each and every time (Brown & Rothery, 1993). Cellular automata are widely used to solve diffusion problems in physiological systems. The set of variables is renewed, at regular intervals, using the same renewal rule for every point. The rules are local in space and time, that is, their value in a point at time t depends only on the values of neighbouring points at time t-1 (Deutsch & Dormann, 2003). ANNs can be used to simulate complex physiological/biological systems, such as the glucose metabolism, presented in the next paragraph. Their wide use in the simulation of non-linear systems is due to their ability to extract hidden data information, and to efficiently approximate any function of many variables.
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