Author Archives: chzechze

Kaposi’s sarcoma Part 2

Mouth

Is involved in about 30%, and is the initial site in 15% of AIDS-related KS. In the mouth, the hard palate is most frequently affected, followed by the gums. Lesions in the mouth may be easily damaged by chewing and bleed or suffer secondary infection, and even interfere with eating or speaking. Continue reading →

Kaposi’s sarcoma Part 1

Kaposi’s sarcoma (KS) is a tumor caused by Human herpesvirus 8 (HHV8), also known as Kaposi’s sarcoma-associated herpesvirus (KSHV). It was originally described by Moritz Kaposi (KA-po-she), a Hungarian dermatologist practicing at the University of Vienna in 1872. It became more widely known as one of the AIDS defining illnesses in the 1980s. The viral cause for this cancer was discovered in 1994. Although KS is now well-established to be caused by a virus infection, there is widespread lack of awareness of this even among persons at risk for KSHV/HHV-8 infection. Continue reading →

Progeria Part 2

A type of anticancer drug, the farnesyltransferase inhibitors (FTIs), has been proposed, but their use has been mostly limited to animal models. A Phase II clinical trial using the FTI lonafarnib began in May 2007. In studies on the cells another anti-cancer drug, rapamycin, caused removal of progerin from the nuclear membrane through autophagy. It has been proved that pravastatin and zoledronate are effective drugs when it comes to the blocking of farnesyl group production. However, it is important to remember that no treatment is able to cure progeria. Continue reading →

Progeria Part 1

Progeria (also known as “Hutchinson–Gilford Progeria Syndrome“, “Hutchinson–Gilford syndrome“, and “Progeria syndrome“) is an extremely rare genetic condition wherein symptoms resembling aspects of aging are manifested at an early age. The word progeria comes from the Greek words “pro” (πρό), meaning “before”, and “géras” (γῆρας), meaning “old age”. The disorder has very low incidences and occurs in an estimated 1 per 8 million live births. Those born with progeria typically live to their mid teens and early twenties. It is a genetic condition that occurs as a new mutation (de novo), and is rarely inherited. Although the term progeria applies strictly speaking to all diseases characterized by premature aging symptoms, and is often used as such, it is often applied specifically in reference to Hutchinson-Gilford Progeria Syndrome (HGPS). Continue reading →

Hurler’s Syndrome

Hurler syndrome, also known as mucopolysaccharidosis type I (MPS I), Hurler’s disease, also gargoylism, is a genetic disorder that results in the buildup of glycosaminoglycans (formerly known as mucopolysaccharides) due to a deficiency of alpha-L iduronidase, an enzyme responsible for the degradation of mucopolysaccharides in lysosomes. Without this enzyme, a buildup of heparan sulfate and dermatan sulfate occurs in the body. Symptoms appear during childhood and early death can occur due to organ damage. Continue reading →

Chediak-Higashi syndrome

Chédiak–Higashi syndrome is a rare autosomal recessive disorder that arises from a microtubule polymerization defect which leads to a decrease in phagocytosis. The decrease in phagocytosis results in recurrent pyogenic infections, partial albinism and peripheral neuropathy. It occurs in humans, cattle, white tigers, blue Persian cats, Australian blue rats, mice, mink, foxes, and the only known captive albino orca. Continue reading →

Apert syndrome Part 2

Causes

Acrocephalosyndactyly may be an autosomal dominant disorder. Males and females are affected equally; however research is yet to determine an exact cause. Nonetheless, almost all cases are sporadic, signifying fresh mutations or environmental insult to the genome. The offspring of a parent with Apert syndrome has a 50% chance of inheriting the condition. In 1995, A.O.M. Wilkie published a paper showing evidence that acrocephalosyndactyly is caused by a defect on the fibroblast growth factor receptor 2 gene, on chromosome 10. Continue reading →

Apert syndrome Part 1

Apert syndrome is a form of acrocephalosyndactyly, a congenital disorder characterized by malformations of the skull, face, hands and feet. It is classified as a branchial arch syndrome, affecting the first branchial (or pharyngeal) arch, the precursor of the maxilla and mandible. Disturbances in the development of the branchial arches in fetal development create lasting and widespread effects. Continue reading →

Dentinogenesis

Odontoblasts

Dentin-forming cells, odontoblasts, which originate from the ectomesenchyme, form a single layer of cells between the dentin and pulp. The cell body is located on the pulpal wall of dentin and the cellular process extends into the dentinal tubule within the mineralized dentin. The cell bodies are from 3 to 5 m wide and 20 to 40 m long depending on the age of the tooth. The odontoblastic process fills the lumen of the dentin tubule and it is composed of a main trunk, with a diameter of 0.5 to 1 m, and lateral branches. Contrary to the cell body, cell organelles (Golgi apparatus, rough endoblastic reticulum or mitochondria) usually do not appear in the odontoblastic process; however, microtubules, filaments and coated vesicles are present. Odontoblasts are connected to each other with interodontoblastic collagen, the so-called von Korff fibers. Frequent bundles of collagen fibrils enter the odontoblast layer from predentin and are present between odontoblast cell bodies. Ultimately they pass through the odontoblast layer into pulp. Histologically, secretory odontoblasts are columnar in shape. A large number of cytoplasmic organelles are identifiable in young odontoblasts, whereas, aged odontoblasts lose their columnar shape and contain a small number of Golgi apparatus and a small-sized rough endoblasmic reticulum. Continue reading →