|
Alzheimer's disease (AD), also called Alzheimer disease or simply Alzheimer's, is the most common cause of dementia, afflicting 24 million people worldwide. Alzheimer's is a degenerative and terminal disease for which there is currently no known cure. In its most common form, it occurs in people over 65 years old although a less-prevalent early-onset form also exists.[1] The disease can begin many years before it is eventually diagnosed. In its early stages, short-term memory loss is the most common symptom, often initially thought to be caused by aging or stress by the sufferer.[2] Later symptoms include confusion, anger, mood swings, language breakdown, long-term memory loss, and the general withdrawal of the sufferer as his or her senses decline.[2][3] Gradually the sufferer loses minor, and then major bodily functions, until death occurs.[4] Although the symptoms are common, each individual experiences the symptoms in unique ways.[5] The duration of the disease is estimated as being between 5 and 20 years.[6][7] Aloysius Alois Alzheimer (14 June 1864, Marktbreit, Bavaria - 19 December 1915, Breslau, now Wrocław, Poland) was a German psychiatrist and neuropathologist and a colleague of Emil Kraepelin. ...
Alzheimer may refer to: Alzheimers disease, a neurodegenerative disease Alois Alzheimer, the neuropathologist who characterized the disease that bears his name Alzheimers Society Alzheimers Association Alzheimer, a record by Spanish metal rap band Def Con Dos. ...
Image File history File linksMetadata Alzheimer_dementia_(3)_presenile_onset. ...
Histopathology is a field of pathology which specialises in the histologic study of diseased tissue. ...
The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ...
The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ...
// G00-G99 - Diseases of the nervous system (G00-G09) Inflammatory diseases of the central nervous system (G00) Bacterial meningitis, not elsewhere classified (G01) Meningitis in bacterial diseases classified elsewhere (G02) Meningitis in other infectious and parasitic diseases classified elsewhere (G03) Meningitis due to other and unspecified causes (G04) Encephalitis, myelitis...
// F00-F99 - Mental and behavioural disorders (F00-F09) Organic, including symptomatic, mental disorders (F00) Dementia in Alzheimers disease (F01) Vascular dementia (F011) Multi-infarct dementia (F02) Dementia in other diseases classified elsewhere (F020) Dementia in Picks disease (F021) Dementia in Creutzfeldt-Jakob disease (F022) Dementia in Huntingtons...
The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ...
The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ...
The Mendelian Inheritance in Man project is a database that catalogues all the known diseases with a genetic component, and - when possible - links them to the relevant genes in the human genome. ...
The Disease Bold textDatabase is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ...
MedlinePlus (medlineplus. ...
eMedicine is an online clinical medical knowledge base that was founded in 1996. ...
Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ...
For other uses, see Dementia (disambiguation). ...
A degenerative disease is a disease in which the function or structure of the affected tissues or organs will progressively deteriorate over time, whether due to normal bodily wear or lifestyle choices such as exercise or eating habits. ...
This article is about incurable disease. ...
Familial Alzheimers disease (FAD) is an uncommon form of Alzheimers disease that comes on earlier in life, defined as before the age of 65 (usually between 30 and 65 years of age) and is inherited in an autosomal dominant fashion. ...
Short-term memory, sometimes referred to as primary, working, or active memory, is said to hold a small amount of information for about 20 seconds. ...
In medical terms, stress is the disruption of homeostasis through physical or psychological stimuli. ...
Severe confusion of a degree considered pathological usually refers to loss of orientation (ability to place oneself correctly in the world by time, location, and personal identity), and often memory (ability to correctly recall previous events or learn new materal). ...
This article is about the emotion. ...
A mood swing is an extreme or rapid change in mood. ...
Long-term memory (LTM) is memory, stored as meaning, that can last as little as 30 seconds or as long as decades. ...
For other uses, see Death (disambiguation). ...
The symptoms of Alzheimer's disease are generally reported to a physician when memory-loss causes concern, and on suspecting Alzheimer’s disease, the physician or healthcare specialists will confirm the diagnosis with a behavioral assessment and cognitive tests, often followed by a brain scan.[8] For other uses, see Doctor. ...
Neuroimaging includes the use of various techniques to either directly or indirectly image the structure, function, or pharmacology of the brain. ...
The cause and progression of Alzheimer's disease is not well understood, but is associated with plaques and tangles in the brain.[9] Possible causes and potential cures of the disease have been conjectured, with varying evidence supporting each claim. No treatment has been found to stop or reverse the disease, and it is not known whether current treatments slow the progression, or simply manage the symptoms. Many preventative measures have been suggested for Alzheimer's disease, but their value is unproven in reducing the course and severity of the disease. Mental stimulation, exercise and a balanced diet are often recommended, both as a possible prevention and as a sensible way of managing the disease.[10] Senile plaques are clumps of A-beta peptides commonly found in Alzheimers disease on microscopic examination of brain tissue. ...
Neurofibrillary tangles are pathological protein aggregates found within neurons in cases of Alzheimers disease. ...
For other uses, see Brain (disambiguation). ...
The term Exercise can refer to: Physical exercise such as running or strength training Exercise (options), the financial term for enacting and terminating a contract Category: ...
Fresh Vegetables A healthy diet contains a balance of food groups and all the nutrients necessary to promote good health. ...
Due to the incurable and degenerative nature of the disease, care-management of Alzheimer's is essential. The role of the main caregiver is often taken by the spouse or a close relative.[11] Caregivers may themselves suffer from stress, over-work, depression, and being physically hit or struck.[12] Stress has different meanings in different fields: Look up stress in Wiktionary, the free dictionary. ...
On the Threshold of Eternity. ...
Characteristics The disease course is typically divided into four stages, with a different pattern of cognitive and functional impairment occurring at each stage. Look up functional in Wiktionary, the free dictionary. ...
The term disability, as it is applied to humans, refers to any condition that impedes the completion of daily tasks using traditional methods. ...
Predementia Detailed neuropsychological testing can reveal mild cognitive difficulties up to eight years before a person fulfills clinical criteria of diagnosis.[13] It is not yet clear if these early symptoms affect daily living activities. Recent studies show impairments in the most complex activities.[14] The most noticeable deficit is short-term memory loss and the resultant inability to acquire new information. In addition, subtle executive problems or semantic memory impairments can also occur.[15][16] Apathy can be observed at this stage, and is the most common and persistent neuropsychiatric symptom throughout the course of the disease.[17][18][19] This stage of the disease has also been termed mild cognitive impairment,[20] but there is still a debate on whether this term corresponds to a different diagnostic entity by itself or just a first step of the disease.[21] Neuropsychology is a branch of psychology and neurology that aims to understand how the structure and function of the brain relate to specific psychological processes and overt behaviors. ...
In general, diagnosis (plural diagnoses) has two distinct dictionary definitions. ...
Activities of daily living (ADLs), is a way to describe the functional status of a person. ...
Short-term memory, sometimes referred to as primary, working, or active memory, is said to hold a small amount of information for about 20 seconds. ...
Executive functions is a term synonymous with cognitive control, and used by psychologists and neuroscientists to describe a loosely defined collection of brain processes whose role is to guide thought and behaviour in accordance with internally generated goals or plans. ...
Semantic memory refers to the memory of meanings, understandings, and other factual knowledge; in contrast to episodic memory. ...
This article does not cite any references or sources. ...
Neuropsychiatry is the branch of medicine dealing with mental disorders attributable to diseases of the nervous system. ...
Mild cognitive impairment (MCI) is a diagnosis given to individuals who have cognitive impairments beyond that expected for their age and education, but that do not interfere significantly with their daily activities [1]. MCI is also used interchangeably with incipient dementia, or isolated memory impairment. ...
Early dementia  In 1994 United States ex-president R. Reagan informed the country of his AD diagnosis via a hand-written letter. Writing is usually affected in the first stages of the disease. In most people with the disease the increasing impairments in learning and memory will lead to diagnosis, while in a small proportion of them language, executive or visuoconstructional difficulties will be more salient.[22] Nevertheless, memory problems do not affect all memory subcapacities equally. Older memories of the patient's life (episodic memory), facts learned (declarative memory), and implicit memory (the memory of the body on how to do things, such as using a knife to eat) are affected to a much lesser degree than the capacities needed to learn new facts or make new memories.[23][24] Language problems are mainly characterized by a shrinking vocabulary and a decreased word fluency which leads to a general impoverishment of oral and written language. The Alzheimer's patient is usually capable of adequately communicating basic ideas.[25][26][27] While performing fine motor tasks such as writing, drawing or dressing, certain visoconstructional difficulties, or apraxia, may be present, which may appear as clumsiness.[28] As the disease progresses to the middle stage, patients might still be able to live and perform tasks independently for most of the time, but may need assistance or supervision with the most complicated activities.[22] Reagan redirects here. ...
Ronald Reagan A portion of the two-page, handwritten letter Ronald Reagans Alzheimers letter was a hand-written letter authored by former United States President Ronald Reagan in November 1994, disclosing the fact he had recently been diagnosed with having Alzheimers disease and was departing from public...
Long-term memory (LTM) is memory, stored as meaning, that can last as little as 30 seconds or as long as decades. ...
Episodic memory, or autobiographical memory, a sub-category of declarative memory, is the recollection of events. ...
It has been suggested that Explicit_memory be merged into this article or section. ...
Procedural memory is the long-term memory of skills and procedures, or how to knowledge. ...
Semantic memory refers to the memory of meanings, understandings, and other factual knowledge; in contrast to episodic memory. ...
The vocabulary of a person is defined either as the set of all words that are understood by that person or the set of all words likely to be used by that person when constructing new sentences. ...
Fluency is the property of a person or of a system that delivers information quickly and with expertise. ...
Fine motor skills can be defined as small muscle movements which occur in the fingers, in coordination with the eyes. ...
Apraxia is a neurological disorder characterized by loss of the ability to execute or carry out learned (familiar) movements, despite having the desire and the physical ability to perform the movements. ...
Look up clumsy, clumsiness in Wiktionary, the free dictionary. ...
Moderate dementia In the early stage, people with Alzheimer's can usually care for themselves. At the moderate stage, progressive deterioration seriously hinders the possibility of independence.[22] Language difficulties become clearly noticeable: the person makes frequent paraphasias due to difficulties in finding words, and content is poor. Reading and writing are also progressively forgotten.[25][29] As time passes, complex motor sequences become less coordinated, costing the patient most of their daily-living abilities.[30] Memory problems worsen, and the person may not recognize close relatives.[31] Long-term memory, which was previously left intact, is now also impaired.[32] Patients are usually almost completely unaware of their own deficits, and behavior changes are the norm. Common neuropsychiatric manifestations in this stage are irritability and labile affect, leading to crying or outbursts of unpremeditated aggression and physical violence, even in patients whose life-long behavior has been peaceful. Approximately 30% of the patients also develop illusionary misidentifications and other delusional symptoms.[17][33] Often urinary incontinence develops.[34] Because of the communication deficit along with delusions, patients often resist when caregivers attempt to provide care.[35] It is important to prevent escalation of resistiveness to care into combativeness when patient might strike out. All these symptoms create stress for relatives and caretakers, increasing the likelihood of moving the patient from home care to other long-term care facilities.[22][36] Paraphasia (also known as paragrammatism) is a notable feature of aphasia (also known as dysphasia) in which one loses the ability of speaking correctly, substitutes one word for another, and changes words and sentences in an inappropriate way. ...
Neuropsychiatry, as a subspecialty of Psychiatry, is the branch of medicine dealing with mental disorders attributable to diseases of the nervous system. ...
Irritability is an excessive response to stimuli. ...
Labile affect or Pseudobulbar affect refers to the pathological expression of laughter, crying, or smiling. ...
In psychology and other social and behavioral sciences, aggression refers to behavior that is intended to cause harm or pain. ...
Delusional misidentification syndrome is an umbrella term for a group of delusional disorders that occur in the context of mental or neurological illness. ...
A delusion is commonly defined as a fixed false belief and is used in everyday language to describe a belief that is either false, fanciful or derived from deception. ...
In medical terms, stress is the disruption of homeostasis through physical or psychological stimuli. ...
Home Care, AKA. domiciliary care, is health care provided in the patients home by healthcare professionals (often referred to as home health care or formal care; in the United States, it is known as skilled care) or by family and friends (also known as caregivers, primary caregiver, or voluntary...
Advanced In the last stage of Alzheimer's disease all human behavior is likely to become entirely automatic. Language is reduced to simple phrases or even single words before being lost altogether.[25] Nevertheless many patients can receive and return emotional signals long after the loss of verbal language.[37] Although aggressiveness can still be present, extreme apathy and exhaustion are much more common.[22] Patients will ultimately not be able to perform even the most simple tasks independently. Finally, deterioration of muscle and mobility will develop, leading the patient to become bedridden[38] and to lose the ability to feed oneself[39] if death from some external cause, such as infection due to pressure ulcers or pneumonia, does not occur first.[40][41] For the Björk song, see Human Behaviour Human behavior is the collection of behaviors exhibited by human beings and influenced by culture, attitudes, emotions, values, ethics, authority, rapport, hypnosis, persuasion, coercion and/or genetics. ...
This article does not cite any references or sources. ...
Fatigue is a feeling of excessive tiredness or lethargy, with a desire to rest, perhaps to sleep. ...
A top-down view of skeletal muscle Muscle is the contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. ...
Bedsores, also called pressure sores or decubitus ulcers, are ulcers (sores) caused by prolonged pressure or rubbing on vulnerable areas of the body. ...
This article is about human pneumonia. ...
Causes Most cases of Alzheimer's disease do not exhibit familial inheritance. At least 80% of sporadic AD cases involve genetic risk factors. Inheritance of the ε4 allele of the apolipoprotein E (ApoE) gene is regarded as a risk factor for development of up to 50% of late-onset sporadic Alzheimer's. The presence of this gene allele along with infection by Herpes simplex virus type 1 (HSV-1) further increases the risk of Alzheimer's disease. Several viral-host interactions are postulated, most relating to HSV-1’s targeting of Alzheimer’s susceptibility genes.[42][43] Genetic experts agree that there are other risk and protective factor genes that influence the development of late onset Alzheimer's disease. Over 400 genes have been tested for association with late-onset sporadic AD.[44] [45] An allele (pronounced , ) (from the Greek αλληλος, meaning each other) is one member of a pair or series of different forms of a gene. ...
Apolipoprotein E (APOE), a main apoprotein of the chylomicron, binds to a specific receptor on liver cells and peripheral cells. ...
This article is about the disease. ...
Five to ten percent of AD cases involve a clear familial pattern of inheritance in which the patient has at least two first-degree relatives with a history of AD. These cases often have an early age of onset (usually younger than sixty years). Nearly 200 different mutations in the presenilin-1 or presenilin-2 genes have been documented in over 500 families. Mutations of presenilin 1 (PS1) lead to the most aggressive form of familial Alzheimer's disease. Over twenty different mutations in the amyloid precursor protein (APP) gene on chromosome 21 can also cause early onset of the disease. The presenilins have been identified as essential components of the proteolytic processing machinery that produces beta amyloid peptides through cleavage of APP. Most mutations in the APP and presenilin genes increase the production of a small protein (peptide) called Abeta42, the main component of senile plaques in brains of AD patients.[46] Presenilins are a family of related multi-pass transmembrane proteins that function as a part of the gamma-secretase protease complex. ...
Familial Alzheimers disease (FAD) is an uncommon form of Alzheimers disease that comes on earlier in life, defined as before the age of 65 (usually between 30 and 65 years of age) and is inherited in an autosomal dominant fashion. ...
The metal-binding domain of APP with a bound copper ion. ...
Chromosome 21 is one of the 23 pairs of chromosomes in humans. ...
Proteolysis is the directed degradation (digestion) of proteins by cellular enzymes called proteases or by intramolecular digestion. ...
Pathophysiology -
Alzheimers disease (AD), one of the most common causes of adult dementia, is as yet not well understood at the molecular level. ...
Neuropathology
 MRI images of a normal aged brain (right) and an Alzheimer's patient's brain (left). In the Alzheimer brain, atrophy is clearly seen. At a macroscopic level, AD is characterized by loss of neurons and synapses in the cerebral cortex and certain subcortical regions. This results in gross atrophy of the affected regions, including degeneration in the temporal lobe and parietal lobe, and parts of the frontal cortex and cingulate gyrus.[47] Image File history File links Alzheimer's_disease_-_MRI.jpg‎ Beskrivelse Source: http://rst. ...
Image File history File links Alzheimer's_disease_-_MRI.jpg‎ Beskrivelse Source: http://rst. ...
The mri are a fictional alien species in the Faded Sun Trilogy of C.J. Cherryh. ...
Macroscopic is commonly used to describe physical objects that are measurable and observable by the naked eye. ...
This article is about cells in the nervous system. ...
Illustration of the major elements in a prototypical synapse. ...
For other uses, see Cortex. ...
Atrophy is the partial or complete wasting away of a part of the body. ...
The temporal lobes are part of the cerebrum. ...
The parietal lobe is a lobe in the brain. ...
The frontal lobe is an area in the brains of vertebrates. ...
Cingulate gyrus is a gyrus in the medial part of the brain. ...
Both amyloid plaques and neurofibrillary tangles are clearly visible by microscopy in AD brains.[9] Plaques are dense, mostly insoluble deposits of amyloid-beta protein and cellular material outside and around neurons. Tangles are insoluble twisted fibers that build up inside the nerve cell. Though many older people develop some plaques and tangles, the brains of AD patients have them to a much greater extent and in different brain locations.[48] For other uses, see Amyloid (disambiguation). ...
Neurofibrillary tangles are pathological protein aggregates found within neurons in cases of Alzheimers disease. ...
Microscopy is any technique for producing visible images of structures or details too small to otherwise be seen by the human eye, using a microscope or other magnification tool. ...
Insoluble Not soluble ...
A representation of the 3D structure of myoglobin showing coloured alpha helices. ...
Look up cell in Wiktionary, the free dictionary. ...
Biochemical characteristics Alzheimer's disease has been identified as a protein misfolding disease, or proteopathy, due to the accumulation of abnormally folded A-beta and tau proteins in the brains of AD patients.[49] Plaques are made of a small peptide (39 to 43 amino acid residues) called beta-amyloid (also A-beta or Aβ), a protein fragment snipped from a larger protein called amyloid precursor protein (APP). APP is a transmembrane protein; which means that it sticks through the neuron's membrane; and is believed to help neurons grow, survive and repair themselves after injury.[50][51] In AD, something causes APP to be divided by enzymes through a mechanism called proteolysis.[52] One of these fragments is beta-amyloid. Beta-amyloid fragments (amyloid fibrils) outside the cell come together into clumps that deposit outside neurons in dense formations known as senile plaques.[53][9] Protein before and after folding. ...
Proteopathy (Proteo- [pref. ...
Peptides (from the Greek πεπτος, digestible), are the family of short molecules formed from the linking, in a defined order, of various α-amino acids. ...
Amyloid beta (Aβ or Abeta) is a protein fragment of 39-42 amino acids that is the main constituent of amyloid plaques in various neurological disorders, most prominently Alzheimers disease. ...
A representation of the 3D structure of myoglobin showing coloured alpha helices. ...
The metal-binding domain of APP with a bound copper ion. ...
A transmembrane protein is a protein that spans the entire biological membrane. ...
Neuraminidase ribbon diagram An enzyme (in Greek en = in and zyme = blend) is a protein, or protein complex, that catalyzes a chemical reaction and also controls the 3D orientation of the catalyzed substrates. ...
Proteolysis is the directed degradation (digestion) of proteins by cellular enzymes called proteases or by intramolecular digestion. ...
Amyloid beta (Aβ or Abeta) is a protein fragment of 39-42 amino acids that is the main constituent of amyloid plaques in various neurological disorders, most prominently Alzheimers disease. ...
Senile plaques are clumps of A-beta peptides commonly found in Alzheimers disease on microscopic examination of brain tissue. ...
AD is also considered a tauopathy due to abnormal aggregation of the tau protein. Healthy neurons have an internal support structure, or cytoskeleton, partly made up of structures called microtubules. These microtubules act like tracks, guiding nutrients and molecules from the body of the cell down to the ends of the axon and back. A special kind of protein, tau, makes the microtubules stable through a process named phosphorylation and is therefore called a microtubule-associated protein.[54] In AD, tau is changed chemically, becoming hyperphosphorylated. Tauopathy is a neurodegenerative disease resulting from the aggregation of tau protein. ...
Tau proteins are normal proteins found within the brain. ...
The eukaryotic cytoskeleton. ...
Microtubules are protein structures found within cells. ...
An axon or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neurons cell body or soma. ...
A phosphorylated serine residue Phosphorylation is the addition of a phosphate (PO4) group to a protein molecule or a small molecule. ...
In cell biology, microtubule-associated proteins (MAPs) are proteins that interact with the microtubules of the cellular cytoskeleton. ...
Hyperphosphorylation occurs when a biochemical with multiple phosphorylation sites is fully saturated. ...
Disease mechanism Three major competing hypotheses exist to explain the cause of the disease. The oldest, on which most currently available drug therapies are based, is known as the cholinergic hypothesis and suggests that AD is due to reduced biosynthesis of the neurotransmitter acetylcholine. However, the medications that treat acetylcholine deficiency only affect symptoms of the disease and neither halt nor reverse it.[55] The cholinergic hypothesis has not maintained widespread support in the face of this evidence, although cholinergic effects have been proposed to initiate large-scale aggregation,[56] leading to generalized neuroinflammation.[47] A synapse is cholinergic if it uses acetylcholine as its neurotransmitter. ...
Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ...
The chemical compound acetylcholine, often abbreviated as ACh, was the first neurotransmitter to be identified. ...
In 1991 the amyloid hypothesis was proposed, [57] while research after 2000 is also centered on tau proteins. The two positions differ with one stating that the tau protein abnormalities initiate the disease cascade, while the other states that amyloid beta (Aβ) deposits are the causative factor in the disease.[58] Amyloid beta (Aβ or Abeta) is a peptide of 39–43 amino acids that is the main constituent of amyloid plaques in the brains of Alzheimers disease patients. ...
Tau proteins are normal proteins found within the brain. ...
The tau hypothesis is supported by the long-standing observation that deposition of amyloid plaques does not correlate well with neuron loss,[59]. In this model, hyperphosphorylated tau begins to pair with other threads of tau and they become tangled up together inside nerve cell bodies in masses known as neurofibrillary tangles.[60] When this happens, the microtubules disintegrate, collapsing the neuron's transport system. This may result first in malfunctions in communication between neurons and later in the death of the cells.[61] Neurofibrillary tangles are pathological protein aggregates found within neurons in cases of Alzheimers disease. ...
A majority of researchers support the alternative hypothesis that Aβ is the primary causative agent.[58] The amyloid hypothesis is compelling because the gene for the amyloid beta precursor (APP) is located on chromosome 21, and patients with trisomy 21 (Down Syndrome) who thus have an extra gene copy almost universally exhibit AD-like disorders by 40 years of age.[62][63] It should be noted further that ApoE4, the major genetic risk factor for AD, leads to excess amyloid build-up in the brain before AD symptoms arise. Thus, Aβ deposition precedes clinical AD.[64] It is known that some types of inherited AD involve only mutations in the APP gene (although this is not the most common type-- others involve genes for "pre-senilin" proteins which process APP and may also have still-unknown functions). [65] However, another strong support for the amyloid hypothesis, which looks at Aβ as the common initiating factor for Alzheimer's disease, is that transgenic mice solely expressing a mutant human APP gene develop fibrillar amyloid plaques.[66] Chromosome 21 is one of the 23 pairs of chromosomes in humans. ...
A child with Down syndrome Down syndrome (also called Downs syndrome) encompasses a number of genetic disorders, of which trisomy 21 (a nondisjunction) is the most representative, causing highly variable degrees of learning difficulties and physical disabilities. ...
Gene dosage is the number of copies of a gene present in a cell or nucleus. ...
Apolipoprotein E (APOE), a main apoprotein of the chylomicron, binds to a specific receptor on liver cells and peripheral cells. ...
GMO redirects here. ...
If damage from Aβ is the primary initiating cause of AD, the exact mechanism has not been elucidated. The traditional formulation of the amyloid hypothesis points to the cytotoxicity of mature aggregated amyloid fibrils, which are believed to be the toxic form of the protein responsible for disrupting the cell's calcium ion homeostasis and thus inducing apoptosis.[67] It is also known that Aβ selectively builds up in the mitochondria of samples from the brains of humans with AD, and in mitochondria from transgenic mice with APP genes, and in both cases inhibits certain mitochondrial enzyme functions, and a similar decrease in glucose utilization in neurons to the one which is a known characteristic of AD. This process may also lead to the formation of damaging reactive oxygen species, calcium influx, and apoptosis. Mechanisms which involve direct damage from Aβ before it forms fibrils and plaques also address the issue that neuronal damage is not correlated as well with plaques, since in this model it is not the plaques themselves which cause the major damage, but rather the precursor Aβ protein directly, via another mechanism. [68] A section of mouse liver showing an apoptotic cell indicated by an arrow Apoptosis (pronounced apo tÅ sis) is a process of suicide by a cell in a multicellular organism. ...
Various inflammatory processes and inflammatory cytokines may also have a hand in the pathology of Alzheimer's disease. However, these are general markers of tissue damage in any disease, and may also be either secondary causes of tissue damage in AD, or else bystander "marker" effects. [69]
Diagnosis Dementia is by definition a clinical condition but not an exact diagnosis. Alzheimer's disease is usually diagnosed clinically from the patient history, collateral history from relatives, and clinical observations, based on the presence of characteristic neurological and neuropsychological features and the absence of alternative conditions.[70][71] Advanced medical imaging with CT or MRI are generally used to help to diagnose the subtype of dementia and exclude other cerebral pathology.[72] Neuropsychological evaluation including memory testing and assessment of intellectual functioning can further characterize the dementia.[73] Medical organizations have created diagnostic criteria to ease and standardize the process for practicing physicians. Sometimes the diagnoses can be confirmed or made at postmortem when brain material is available and can be examined histologically and histochemically.[74] For other uses, see Dementia (disambiguation). ...
Neurology is a branch of medicine dealing with disorders of the nervous system. ...
Neuropsychology is a branch of psychology and neurology that aims to understand how the structure and function of the brain relate to specific psychological processes and overt behaviors. ...
The term diagnosis of exclusion (per exclusionem) refers to a medical condition whose presence cannot be established with complete confidence from examination or testing. ...
Medical imaging designates the ensemble of techniques and processes used to create images of the human body (or parts thereof) for clinical purposes (medical procedures seeking to reveal, diagnose or examine disease) or medical science (including the study of normal anatomy and function). ...
negron305 Cat scan redirects here. ...
MRI redirects here. ...
Diagnostic criteria The diagnostic criteria for Alzheimer of the NINCDS-ADRDA (NINCDS and the ADRDA) are among the most used.[75] These criteria require that the presence of cognitive impairment and a suspected dementia syndrome be confirmed by neuropsychological testing for a clinical diagnosis of possible or probable AD while they need histopathologic confirmation (microscopic examination of brain tissue) for the definitive diagnosis. They have shown good reliability and validity.[76] They specify as well eight cognitive domains that may be impaired in AD (i.e., memory, language, perceptual skills, attention, constructive abilities, orientation, problem solving and functional abilities). Similar to the NINCDS-ADRDA Alzheimer's Criteria are the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) criteria published by the American Psychiatric Association.[77][78] Neuropsychological assessment was traditionally carried out to assess the extent of impairment to a particular skill and to attempt to locate an area of the brain which may have been damaged after brain injury or neurological illness. ...
Histopathology is a field of pathology which specialises in the histologic study of diseased tissue. ...
A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ...
The human brain controls the central nervous system (CNS), by way of the cranial nerves and spinal cord, the peripheral nervous system (PNS) and regulates virtually all human activity. ...
In statistics, reliability is the consistency of a set of measurements or measuring instrument, often used to describe a test. ...
In psychology, validity has two distinct fields of application. ...
For other uses, see Memory (disambiguation). ...
In psychology and the cognitive sciences, perception is the process of acquiring, interpreting, selecting, and organizing sensory information. ...
This article is about psychological concept of attention. ...
Orientation is a function of the mind involving awareness of three dimensions: time, place and person. ...
Problem solving forms part of thinking. ...
The Diagnostic and Statistical Manual published by the American Psychiatric Association The Diagnostic and Statistical Manual of Mental Disorders (DSM) is a handbook for mental health professionals that lists different categories of mental disorder and the criteria for diagnosing them, according to the publishing organization the American Psychiatric Association. ...
Due to the epidemic of medical errors, readers are cautioned to be aware that the American Psychiatric Association isnt immune to this. ...
Diagnostic tools
 Neuropsychological screening tests can help in the diagnosis of AD. In them patients have to copy drawings similar to the one shown in the picture, remember words, read or sum. Neuropsychological screening tests as the Mini mental state examination (MMSE) are widely used to evaluate the cognitive impairments needed for diagnosis, but more comprehensive batteries are necessary for high reliability by this method; especially in the earliest stages of the disease.[79][80] On the other hand neurological examination in early AD will usually be normal, independent of cognitive impairment; but for many of the other dementing disorders is key for diagnosis. Therefore, neurological examination is crucial in the differential diagnosis of Alzheimer and other diseases.[73] In addition, interviews with family members are also utilized in the assessment of the disease. Caregivers can supply important information on the daily living abilities, as well as on the decrease over time of the patient's mental function.[81] This is especially important since a patient with AD is commonly unaware of his or her own deficits (anosognosia).[82] Many times families also have difficulties in the detection of initial dementia symptoms and in adequately communicating them to a physician.[83] Finally supplemental testing provide extra information on some features of the disease or are utilized to rule out other diagnoses. Examples are blood tests, which can identify other causes for dementia different than AD;[73] which rarely may even be reversible;[84] or psychological tests for depression, as depression can both co-occur with AD or on the contrary be at the origin of the patient's cognitive impairment.[85][86] Image File history File links InterlockingPentagons. ...
Image File history File links InterlockingPentagons. ...
Screening, in medicine, is a strategy used to identify disease in an unsuspecting population. ...
The mini mental state examination (MMSE) or Folstein test is a brief 30-point questionnaire test that is used to assess cognition. ...
This article does not cite any references or sources. ...
Anosognosia is a condition in which a person who suffers disability due to brain injury, seems unaware of or denies the existence of their handicap. ...
Blood tests are laboratory tests done on blood to gain an appreciation of disease states and the function of organs. ...
Psychological testing is a field characterized by the use of samples of behavior in order to infer generalizations about a given individual. ...
On the Threshold of Eternity. ...
Increasingly, the functional neuroimaging modalities of single photon emission computed tomography (SPECT) and positron emission tomography (PET) are being used to diagnose Alzheimer's, as they have shown similar ability to diagnose Alzheimer's disease as methods involving mental status examination.[87] Furthermore, the ability of SPECT to differentiate Alzheimer's disease from other possible causes, in a given patient already known to be suffering from dementia, appears to be superior to attempts to differentiate the cause of dementia cause by mental testing and history.[88] A new technique known as "PiB PET" has been developed for directly and clearly imaging beta-amyloid deposits in vivo using a contrasting tracer that binds selectively to the Abeta deposits.[89][90][91] Another recent objective marker of the disease is the analysis of cerebrospinal fluid for amyloid beta or tau proteins.[92] Both advances (neuroimaging and cerebrospinal fluid analysis) have led to the proposal of new diagnostic criteria.[75][73] Functional neuroimaging is the use of neuroimaging technology to measure an aspect of brain function, often with a view to understanding the relationship between activity in certain brain areas and specific mental functions. ...
Single photon emission computed tomography (SPECT) is a nuclear medicine tomographic imaging technique using gamma rays. ...
Image of a typical positron emission tomography (PET) facility Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three-dimensional image or map of functional processes in the body. ...
Mental status examination, or MSE, is a medical process where a clinician working in the field of mental health (usually a social worker, psychiatrist, psychiatric nurse or psychologist) systematically examines a patients mind. ...
Image of a typical positron emission tomography (PET) facility Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three-dimensional image or map of functional processes in the body. ...
In vivo (Latin for (with)in the living). ...
A contrast medium is a radiopaque substance used to facilitate roentgen visualization of internal structures of the body such as the urogenital sinus. ...
A radioactive tracer is a substance containing a radioactive isotope (radioisotope). ...
Molecular binding is a method of molecular interaction to bind together or separate two or more molecules, and is important in the development of new medical drugs and other chemicals. ...
Cerebrospinal fluid (CSF), Liquor cerebrospinalis, is a clear bodily fluid that occupies the subarachnoid space in the brain (the space between the skull and the cerebral cortex—more specifically, between the arachnoid and pia layers of the meninges). ...
Amyloid beta (Aβ or Abeta) is a peptide of 39–43 amino acids that is the main constituent of amyloid plaques in the brains of Alzheimers disease patients. ...
Tau proteins are normal proteins found within the brain. ...
Prevention
 Intellectual activities such as playing chess or regular social interaction have been linked to a reduced risk of AD in epidemiological studies, although no causal relationship has been found. At present contradictory results in global studies, incapacity to prove causal relationships between risk factors and the disease, and possible secondary effects indicate a lack of specific measures to prevent or delay the onset of AD.[93] Different epidemiological studies have proposed relationships between certain modifiable factors, such as diet, cardiovascular risk, pharmaceutical products, or intellectual activities among others, and a population's likelihood of developing AD. Only further research, including clinical trials, will reveal whether, in fact, these factors can help to prevent AD.[94] Image File history File links Download high resolution version (2024x1564, 273 KB) Description: Title: de: Schachspieler Technique: de: Öl auf Leinwand Dimensions: de: 24 × 32 cm Country of origin: de: Frankreich Current location (city): de: Paris Current location (gallery): de: Musée du Petit-Palais Other notes: Source: The Yorck...
Image File history File links Download high resolution version (2024x1564, 273 KB) Description: Title: de: Schachspieler Technique: de: Öl auf Leinwand Dimensions: de: 24 × 32 cm Country of origin: de: Frankreich Current location (city): de: Paris Current location (gallery): de: Musée du Petit-Palais Other notes: Source: The Yorck...
The components of a Mediterranean diet, which include fruit and vegetables, bread, wheat and other cereals, olive oil, fish, and red wine, may all individually or together reduce the risk and course of Alzheimer's disease.[95] Vitamins E, B, and C, or folic acid have appeared to be related to a reduced risk of AD,[96] but other studies indicate that they do not have any significant effect on the onset or course of the disease, while at the same time may have important secondary effects in conjunction with other therapies. [97] Curcumin in curry has shown some effectiveness in preventing brain damage in mouse models.[98] For cuisine, see Cuisine of the Mediterranean. ...
For other uses, see Bread (disambiguation). ...
Species T. aestivum T. boeoticum T. dicoccoides T. dicoccon T. durum T. monococcum T. spelta T. sphaerococcum T. timopheevii References: ITIS 42236 2002-09-22 Wheat Wheat For the indie rock group, see Wheat (band). ...
Grain redirects here. ...
For the Popeye character, see Olive Oyl. ...
For other uses, see Fish (disambiguation). ...
This article is about the beverage. ...
Tocopherol, or Vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. ...
The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ...
This article is about the nutrient. ...
Folic acid and folate (the anion form) are forms of the water-soluble Vitamin B9. ...
Curcumin is the active ingredient of the Indian curry spice turmeric. ...
This article is about the dish. ...
Although cardiovascular risk factors, such as hypercholesterolemia, hypertension, diabetes, and smoking, are associated with a higher risk of onset and course of AD,[99][100] statins, which are cholesterol lowering drugs, have not been effective in preventing or improving the course of the disease.[101][102] However long-term usage of non-steroidal anti-inflammatory drug (NSAIDs), is associated with a reduced likelihood of developing AD in some individuals.[103] Other pharmaceutical therapies such as female hormone replacement therapy are no longer thought to prevent dementia,[104][105] while a 2007 systematic review concluded that there was inconsistent and unconvincing evidence that ginkgo has any positive effect on dementia or cognitive impairment.[106] Hypercholesterolemia (literally: high blood cholesterol) is the presence of high levels of cholesterol in the blood [1]. It is not a disease but a metabolic derangement that can be secondary to many diseases and can contribute to many forms of disease, most notably cardiovascular disease. ...
For other forms of hypertension, see Hypertension (disambiguation). ...
This article is about the disease that features high blood sugar. ...
Lovastatin, the first statin to be marketed The statins form a class of hypolipidemic agents. ...
Cholesterol is a sterol (a combination steroid and alcohol). ...
Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAIDs, are drugs with analgesic, antipyretic and anti-inflammatory effects - they reduce pain, fever and inflammation. ...
Hormone replacement therapy (HRT) is a system of medical treatment for perimenopausal and postmenopausal women, based on the assumption that it may prevent discomfort and health problems caused by diminished circulating estrogen hormones. ...
Systematic reviews are named as the highest level of medical evidence, by evidence based medicine professionals. ...
Binomial name Ginkgo biloba L. The Ginkgo (Ginkgo biloba), sometimes also known as the Maidenhair tree, is a unique tree with no living relatives. ...
Intellectual activities such as playing chess, completing crossword puzzles or regular social interaction, may also delay the onset or reduce the severity of Alzheimer's disease.[107][108] Bilingualism is also related to a later onset of Alzheimer.[109] This article is about the Western board game. ...
A crossword is a word puzzle that normally takes the form of a square grid of black and white squares. ...
A puzzle undone, which forms a cube Puzzle cube; a type of puzzle For other uses, see Puzzle (disambiguation). ...
Social interaction is a dynamic, changing sequence of social actions between individuals (or groups) who modify their actions and reactions due to the actions by their interaction partner(s). ...
Bilingual redirects here. ...
Management There is no known cure for Alzheimer's disease. Available treatments offer relatively small symptomatic benefit but remain palliative in nature. Current treatments can be divided into pharmaceutical, psychosocial and caregiving. Palliative care (from Latin palliare, to cloak) is any form of medical care or treatment that concentrates on reducing the severity of disease symptoms, rather than providing a cure. ...
Pharmaceutical
 Molecular structure of memantine, a medication approved for advanced AD symptoms. Four medications are currently approved to treat the cognitive manifestations of AD by regulatory agencies, including the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMEA). Three are acetylcholinesterase inhibitors and the other is memantine, an NMDA receptor antagonist. No drug has an indication for delaying or halting the progression of the disease. Donepezil, marketed under the trade name Aricept® (Eisai), is a centrally acting reversible acetyl cholinesterase inhibitor. ...
A cholinesterase inhibitor or anticholinesterase is a chemical that inhibits a cholinesterase enzyme from breaking down acetylcholine, so increasing both the level and duration of action of the neurotransmitter acetylcholine. ...
Image File history File links Memantine. ...
Image File history File links Memantine. ...
Memantine is the first in a novel class of Alzheimers disease medications acting on the glutamatergic system by blocking NMDA glutamate receptors. ...
FDA redirects here. ...
The European Medicines Agency (EMEA) is a European agency for the evaluation of medicinal products. ...
A cholinesterase inhibitor or anticholinesterase is a chemical that inhibits a cholinesterase enzyme from breaking down acetylcholine, so increasing both the level and duration of action of the neurotransmitter acetylcholine. ...
Memantine is the first in a novel class of Alzheimers disease medications acting on the glutamatergic system by blocking NMDA glutamate receptors. ...
The NMDA receptor (NMDAR) is an ionotropic receptor for glutamate (NMDA (N-methyl d-aspartate) is a name of its selective specific agonist). ...
Antagonists will block the binding of an agonist at a receptor molecule, inhibiting the signal produced by a receptor-agonist coupling. ...
Because reduction in the activity of the cholinergic neurons in the disease is well known,[110] acetylcholinesterase inhibitors are employed to reduce the rate at which acetylcholine (ACh) is broken down and so to increase the concentration of ACh in the brain, thereby combatting the loss of ACh caused by the death of the cholinergin neurons.[111] Cholinesterase inhibitors currently approved include donepezil (brand name Aricept),[112] galantamine (Razadyne),[113] and rivastigmine (branded as Exelon,[114] and Exelon Patch[115]). There is also evidence for the efficacy of these medications in mild to moderate Alzheimer’s disease,[116] and some evidence for their use in the advanced stage. Only donepezil is approved for treatment of advanced AD dementia.[117] The use of these drugs in mild cognitive impairment has not shown any effect in a delay of the onset of AD.[118] Most common side effects include nausea and vomiting, both of which are linked to cholinergic excess. These side effects arise in approximately 10% to 20% of users and are mild to moderate in severity. Less common secondary effects include muscle cramps; decreased heart rate (bradycardia), decreased appetite and weight, and increased gastric acid.[119][120][121][122] A synapse is cholinergic if it uses acetylcholine as its neurotransmitter. ...
A cholinesterase inhibitor or anticholinesterase is a chemical that inhibits a cholinesterase enzyme from breaking down acetylcholine, so increasing both the level and duration of action of the neurotransmitter acetylcholine. ...
The chemical compound acetylcholine, often abbreviated as ACh, was the first neurotransmitter to be identified. ...
Donepezil, marketed under the trade name Aricept® (Eisai), is a centrally acting reversible acetyl cholinesterase inhibitor. ...
Galantamine (trade name Razadyne®) is a medication used in the treatment of Alzheimers disease. ...
Exelon (rivastigmine tartrate) is a pharmaceutical product developed and marketed by Novartis for the treatment of Alzheimers disease. ...
Mild cognitive impairment (MCI) is a diagnosis given to individuals who have cognitive impairments beyond that expected for their age and education, but that do not interfere significantly with their daily activities [1]. MCI is also used interchangeably with incipient dementia, or isolated memory impairment. ...
Side-effect can mean: Side-effect (computer science), a state change caused by a function call Adverse drug reaction, an unintended consequence specifically arising from drug therapy Therapeutic effect (medicine), a d
|
