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Telangectasia
Telangiectasias, also known as spider veins, are small dilated blood vessels that can occur near the surface of the skin or mucous membranes, measuring between 0.5 and 1 millimeter in diameter. These dilated blood vessels can develop anywhere on the body, but are commonly seen on the face around the nose, cheeks and chin. Dilated blood vessels can also develop on the legs, although when they occur on the legs, they often have underlying venous reflux or "hidden varicose veins" (see Venous hypertension section below). When found on the legs, they are found specifically on the upper thigh, below the knee joint and around the ankles. Many patients with spider veins seek the assistance of physicians who specialize in vein care or peripheral vascular disease. These physicians are called vascular surgeons or phlebologists. More recently, interventional radiologists have started treating venous problems. Some telangiectasias are due to developmental abnormalities that can closely mimic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal-cell Carcinoma
Basal-cell carcinoma (BCC), also known as basal-cell cancer, is the most common type of skin cancer. It often appears as a painless raised area of skin, which may be shiny with small blood vessels running over it. It may also present as a raised area with ulceration. Basal-cell cancer grows slowly and can damage the tissue around it, but it is unlikely to spread to distant areas or result in death. Risk factors include exposure to ultraviolet light, having lighter skin, radiation therapy, long-term exposure to arsenic and poor immune-system function. Exposure to UV light during childhood is particularly harmful. Tanning beds have become another common source of ultraviolet radiation. Diagnosis often depends on skin examination, confirmed by tissue biopsy. It remains unclear whether sunscreen affects the risk of basal-cell cancer. Treatment is typically by surgical removal. This can be by simple excision if the cancer is small; otherwise, Mohs surgery is generally recommen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CREST Syndrome
CREST syndrome, also known as the limited cutaneous form of systemic sclerosis (lcSSc), is a multisystem connective tissue disorder. The acronym "CREST" refers to the five main features: calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia. CREST syndrome is associated with detectable antibodies against centromeres (a component of the cell nucleus), and usually spares the kidneys (a feature more common in the related condition systemic scleroderma). If the lungs are involved, it is usually in the form of pulmonary arterial hypertension. Signs and symptoms Calcinosis CREST causes thickening and tightening of the skin with deposition of calcific nodules ("calcinosis"). Raynaud's phenomenon Raynaud's phenomenon is frequently the first manifestation of CREST/lcSSc, preceding other symptoms by years. Stress and cold temperature induce an exaggerated vasoconstriction of the small arteries, arterioles, and thermoregulatory vessels of the skin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enchondroma
Enchondroma is a type of benign bone tumor belonging to the group of cartilage tumors. There may be no symptoms, or it may present typically in the short tubular bones of the hands with a swelling, pain or pathological fracture. Diagnosis is by X-ray, CT scan and sometimes MRI. Most occur as a less than three centimetre size single tumor. When several occur in one long bone or several bones, the syndrome is called enchondromatosis. Where there are no symptoms, treatment is often not needed. If treatment is required, curettage may be performed. Less than 1% become malignant, unless part of a syndrome. They comprise around 30% of cartilage tumors. 90% of tumors in the hand are enchondromas. Symptoms and signs Individuals with an enchondroma often have no symptoms at all. The following are the most common symptoms of an enchondroma. However, each individual may experience symptoms differently. Symptoms may include: * Pain that may occur at the site of the tumor if the tumor i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maffucci Syndrome
Maffucci syndrome is a very rare disorder in which multiple benign tumors of cartilage develop within the bones (such tumors are known as enchondromas). The tumors most commonly appear in the bones of the hands, feet, and limbs, causing bone deformities and short limbs. It is named for the Italian pathologist Angelo Maffucci who described it in 1881. Fewer than 200 cases of this syndrome have been reported. Signs and symptoms Patients are normal at birth and the syndrome manifests during childhood. The enchondromas affect the extremities and their distribution is asymmetrical. The most common sites of enchondromas are the metacarpal bones and phalanges of the hands. The feet are less commonly affected. Disfigurations of the extremities are a result. Pathological fractures can arise in affected metaphyses and diaphyses of the long bones and are common (26%). The risk for sarcomatous degeneration of enchondromas, hemangiomas, or lymphangiomas is 15–30% in the setting of Maffucci s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naevus Flammeus
A port-wine stain (''nevus flammeus'') is a discoloration of the human skin caused by a vascular anomaly (a capillary malformation in the skin). They are so named for their coloration, which is similar in color to port wine, a fortified red wine from Portugal. A port-wine stain is a capillary malformation, seen at birth. Port-wine stains persist throughout life. The area of skin affected grows in proportion to general growth. Port-wine stains occur most often on the face but can appear anywhere on the body, particularly on the neck, upper trunk, arms and legs. Early stains are usually flat and pink in appearance. As the child matures, the color may deepen to a dark red or purplish color. In adulthood, thickening of the lesion or the development of small lumps may occur. Port-wine stains may be part of a syndrome such as Sturge–Weber syndrome or Klippel–Trénaunay–Weber syndrome. Types Nevus flammeus may be divided as follows:James, William; Berger, Timothy; Elston, D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Repair
DNA repair is a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human cells, both normal metabolic activities and environmental factors such as radiation can cause DNA damage, resulting in tens of thousands of individual molecular lesions per cell per day. Many of these lesions cause structural damage to the DNA molecule and can alter or eliminate the cell's ability to transcribe the gene that the affected DNA encodes. Other lesions induce potentially harmful mutations in the cell's genome, which affect the survival of its daughter cells after it undergoes mitosis. As a consequence, the DNA repair process is constantly active as it responds to damage in the DNA structure. When normal repair processes fail, and when cellular apoptosis does not occur, irreparable DNA damage may occur, including double-strand breaks and DNA crosslinkages (interstrand crosslinks or ICLs). This can eventually lead to malignant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Null Allele
A null allele is a nonfunctional allele (a variant of a gene) caused by a genetic mutation. Such mutations can cause a complete lack of production of the associated gene product or a product that does not function properly; in either case, the allele may be considered nonfunctional. A null allele cannot be distinguished from deletion of the entire locus solely from phenotypic observation. A mutant allele that produces no RNA transcript is called an RNA null (shown by Northern blotting or by DNA sequencing of a deletion allele), and one that produces no protein is called a protein null (shown by Western blotting). A genetic null or amorphic allele has the same phenotype when homozygous as when heterozygous with a deficiency that disrupts the locus in question. A genetic null allele may be both a protein null and an RNA null, but may also express normal levels of a gene product that is nonfunctional due to mutation. Null alleles can have lethal effects depending on the importance o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bloom Syndrome
Bloom syndrome (often abbreviated as BS in literature) is a rare autosomal recessive genetic disorder characterized by short stature, predisposition to the development of cancer, and genomic instability. BS is caused by mutations in the ''BLM'' gene which is a member of the RecQ DNA helicase family. Mutations in other members of this family, namely WRN and RECQL4, are associated with the clinical entities Werner syndrome and Rothmund–Thomson syndrome, respectively. More broadly, Bloom syndrome is a member of a class of clinical entities that are characterized by chromosomal instability, genomic instability, or both and by cancer predisposition. Cells from a person with Bloom syndrome exhibit a striking genomic instability that includes excessive crossovers between homologous chromosomes and sister chromatid exchanges (SCEs). The condition was discovered and first described by New York dermatologist Dr. David Bloom in 1954. Bloom syndrome has also appeared in the older literature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth defects are divided into two main types: structural disorders in which problems are seen with the shape of a body part and functional disorders in which problems exist with how a body part works. Functional disorders include metabolic and degenerative disorders. Some birth defects include both structural and functional disorders. Birth defects may result from genetic or chromosomal disorders, exposure to certain medications or chemicals, or certain infections during pregnancy. Risk factors include folate deficiency, drinking alcohol or smoking during pregnancy, poorly controlled diabetes, and a mother over the age of 35 years old. Many are believed to involve multiple factors. Birth defects may be vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sclerodactyly
Sclerodactyly is a localized thickening and tightness of the skin of the fingers or toes that yields a characteristic claw-like appearance and spindle shape of the affected digits, and renders them immobile or of limited mobility. The thickened, discolored patches of skin are called morphea, and may involve connective tissue below the skin, as well as muscle and other tissues. Sclerodactyly is often preceded by months or even years by Raynaud's phenomenon when it is part of systemic scleroderma. The term "sclerodactyly" comes from the combination of the Greek words "skleros" meaning hard and "daktylos" meaning a finger or toe – "hard fingers or toes". It is generally associated with systemic scleroderma and mixed connective tissue disease, and auto-immune disorders. Sclerodactyly is one component of the limited cutaneous form of systemic sclerosis (lcSSc), also known as CREST syndrome (CREST is an acronym that stands for calcinosis, Raynaud's phenomenon, esophageal dysmot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophageal Motility Disorder
An esophageal motility disorder (EMD) is any medical disorder causing difficulty in swallowing, regurgitation of food and a spasm-type pain which can be brought on by an allergic reaction to certain foods. The most prominent one is dysphagia. Esophageal motility disorder may be a result of CREST syndrome, referring to the five main features: calcinosis, Raynaud syndrome, esophageal dysmotility, sclerodactyly and telangiectasia. Symptoms Symptoms of EMD can include chest pain, and intermittent Dysphagia for solids, liquids, or both, and regurgitation. There are contractions along the lower esophagus, and these contractions prevent the passage of food. Types Dysphagia could be for solids only, or for solids and liquids both. * Solid dysphagia is due to obstructions such as esophageal cancer, esophageal webs, or stricture. * Solid-and-liquid dysphagia is due to an esophageal motility disorder (or dysmotility) either in the upper esophagus (caused by, for example, myasthenia gravis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
