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LEOPARD Syndrome
Noonan syndrome with multiple lentigines (NSML) which is part of a group called Ras/MAPK pathway syndromes, is a rare autosomal dominant, multisystem disease caused by a mutation in the protein tyrosine phosphatase, non-receptor type 11 gene (''PTPN11''). The disease is a complex of features, mostly involving the skin, skeletal and cardiovascular systems, which may or may not be present in all patients. The nature of how the mutation causes each of the condition's symptoms is not well known; however, research is ongoing. It is a RASopathy. Noonan syndrome with multiple lentigines is caused by a different missense mutation of the same gene. Noonan syndrome is fairly common (1:1,000 to 1:2,500 live births), and neurofibromatosis 1 (which was once thought to be related to NSML) is also common (1:3500); however, no epidemiological data exists for NSML. Signs and symptoms An alternative name of the condition, LEOPARD syndrome, is a mnemonic, originally coined in 1969, as the conditi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prognathism
Prognathism is a positional relationship of the mandible or maxilla to the skeletal base where either of the jaws protrudes beyond a predetermined imaginary line in the coronal plane of the skull. In the case of ''mandibular'' prognathism (never maxillary prognathism), this is often also referred to as Habsburg chin, Habsburg's chin, Habsburg jaw or Habsburg's jaw especially when referenced with the context of its prevalence amongst historical members of the House of Habsburg. Mandibular prognathism is typically pathological, whereas maxillary prognathism is often the result of normal human population variation. In general dentistry, oral and maxillofacial surgery, and orthodontics, this is assessed clinically or radiographically ( cephalometrics). The word ''prognathism'' derives from the Greek πρό (''pro'', meaning 'forward') and γνάθος (''gnáthos'', 'jaw'). One or more types of prognathism can result in the common condition of malocclusion, in which an individua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lentigo
A lentigo () (plural lentigines, ) is a small pigmented spot on the skin with a clearly defined edge, surrounded by normal-appearing skin. It is a harmless (benign) hyperplasia of melanocytes which is linear in its spread. This means the hyperplasia of melanocytes is restricted to the cell layer directly above the basement membrane of the epidermis where melanocytes normally reside. This is in contrast to the "nests" of multi-layer melanocytes found in moles (melanocytic nevi). Because of this characteristic feature, the adjective "lentiginous" is used to describe other skin lesions that similarly proliferate linearly within the basal cell layer.''Random House Webster's Unabridged Dictionary.'' Random House, Inc. 2001. p. 1101. .''Robbins and Cotran Pathologic Basis of Disease'' Elsevier. 2005. p. 1232. . Diagnosis Conditions characterized by lentigines include: * Lentigo simplex * Solar lentigo (Liver spots) * PUVA lentigines * Ink spot lentigo * LEOPARD syndrome * Muc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bundle Branch Block
A bundle branch block is a partial or complete interruption in the flow of electrical impulses in either of the bundle branches of the heart's electrical system. Anatomy and physiology The heart's electrical activity begins in the sinoatrial node (the heart's natural pacemaker), which is situated on the upper right atrium. The impulse travels next through the left and right atria and summates at the atrioventricular node. From the AV node the electrical impulse travels down the bundle of His and divides into the right and left bundle branches. The right bundle branch contains one fascicle. The left bundle branch subdivides into two fascicles: the left anterior fascicle, and the left posterior fascicle. Other sources divide the left bundle branch into three fascicles: the left anterior, the left posterior, and the left septal fascicle. The thicker left posterior fascicle bifurcates, with one fascicle being in the septal aspect. Ultimately, the fascicles divide into mill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abnormal
In psychology, abnormality (also dysfunctional behavior, maladaptive behavior, or deviant behavior) is a behavioral characteristic assigned to those with conditions that are regarded as dysfunctional. Behavior is considered to be abnormal when it is atypical or out of the ordinary, consists of undesirable behavior, and results in impairment in the individual's functioning. As applied to humans, abnormality may also encompass deviance, which refers to behavior that is considered to transgress social norms. The definition of abnormal behavior in humans is an often debated issue in abnormal psychology. ''Abnormal'' behavior should not be confused with ''unusual'' behavior. Behavior that is out of the ordinary is not necessarily indicative of a mental disorder. Abnormal behavior, on the other hand, while not a mental disorder in itself, is often an indicator of a possible mental or psychological disorder. A psychological disorder is defined as an "ongoing dysfunctional pattern of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Conduction
Electrical resistivity (also called volume resistivity or specific electrical resistance) is a fundamental specific property of a material that measures its electrical resistance or how strongly it resists electric current. A low resistivity indicates a material that readily allows electric current. Resistivity is commonly represented by the Greek letter (rho). The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). For example, if a solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is , then the resistivity of the material is . Electrical conductivity (or specific conductance) is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter (sigma), but ( kappa) (especially in electrical engineering) and (gamma) are sometimes used. The SI unit of electrical conductivity is siemens per metre (S/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrocardiographic
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity through repeated cardiac cycles. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat). Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including: * Cardiac rhythm disturbances, such as atrial fibrillation and ventricular tachycardia; * Inadequate coronary artery blood flow, such as myocardial ischemia and myocardial infarction; * and electrolyte disturbances, such as hypokalemia. Traditionally, "ECG" usually means a 12-lead ECG taken while lying down as discussed below. However, other devices can record the electrical activity of the heart such as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypopigmentation
Hypopigmentation is characterized specifically as an area of Human skin, skin becoming lighter than the baseline skin color, but not completely devoid of skin pigment, pigment. This is not to be confused with depigmentation, which is characterized as the absence of all pigment. It is caused by melanocyte or melanin depletion, or a decrease in the amino acid tyrosine, which is used by melanocytes to make melanin. Some common genetic causes include mutations in the tyrosinase gene or OCA2 gene. As melanin pigments tend to be in the skin, eye, and hair, these are the commonly affected areas in those with hypopigmentation. Hypopigmentation is common and approximately one in twenty have at least one hypopigmented macule. Hypopigmentation can be upsetting to some, especially those with darker skin whose hypopigmentation marks are seen more visibly. Most causes of hypopigmentation are not serious and can be easily treated. Presentation Associated conditions It is seen in: * Albinism * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitiligo
Vitiligo (, ) is a chronic autoimmune disorder that causes patches of skin to lose pigment or color. The cause of vitiligo is unknown, but it may be related to immune system changes, genetic factors, stress, or sun exposure, and susceptibility to it may be affected by regional environmental risk factors, especially early in life. Treatment options include topical medications, light therapy, surgery and cosmetics. The condition causes patches of a light peachy color of any size, which can appear on any place on the body; in particular, nonsegmental vitiligo, the common form, tends to progress, affecting more of the skin over time. Vitiligo spots on the skin can also vary in pigmentation over long periods, although they will stay in relatively the same areas. Signs and symptoms The only sign of vitiligo is the presence of pale patchy areas of depigmented skin which tend to occur on the extremities. Some people may experience itching before a new patch appears. The patches ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sclera
The sclera, also known as the white of the eye or, in older literature, as the tunica albuginea oculi, is the opaque, fibrous, protective outer layer of the eye containing mainly collagen and some crucial elastic fiber. In the development of the embryo, the sclera is derived from the neural crest. In children, it is thinner and shows some of the underlying pigment, appearing slightly blue. In the elderly, fatty deposits on the sclera can make it appear slightly yellow. People with dark skin can have naturally darkened sclerae, the result of melanin pigmentation. In humans, and some other vertebrates, the whole sclera is white or pale, contrasting with the coloured iris (anatomy), iris. The cooperative eye hypothesis suggests that the pale sclera evolved as a method of nonverbal communication that makes it easier for one individual to identify where another individual is looking. Other mammals with white or pale sclera include chimpanzees, many orangutans, some gorillas, and bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheek
The cheeks () constitute the area of the face below the eyes and between the nose and the left or right ear. ''Buccal'' means relating to the cheek. In humans, the region is innervated by the buccal nerve. The area between the inside of the cheek and the teeth and gums is called the vestibule or ''buccal'' pouch or ''buccal'' cavity and forms part of the mouth. In other animals, the cheeks may also be referred to as " jowls". Structure Cheeks are fleshy in humans, the skin being suspended by the chin and the jaws, and forming the lateral wall of the human mouth, visibly touching the cheekbone below the eye. The inside of the cheek is lined with a mucous membrane (''buccal'' mucosa, part of the oral mucosa). During mastication (chewing), the cheeks and tongue between them serve to keep the food between the teeth. Clinical significance The cheek is the most common location from which a DNA sample can be taken. (Some saliva is collected from inside the mouth, e.g. using a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
