Related Experiment Videos
Parakeratosis variegata: a possible role of environmental hazards?
T T Rogoziński1, C Zekanowski, L Kaldan
1Department of Dermatology, Warsaw School of Medicine, Warsaw, Poland.
Abstract:
We report 2 cases of parakeratosis variegata (PV) evolving from lesions beginning with characteristics of ashy dermatosis. Both patients presented with a reticulated, poikilodermatous and hyperpigmented eruption with bizarre coalescent lichenoid papules. Histology showed lichenoid epidermotropic infiltrates, more pronounced in case No. 1, consistent with early malignancy. The course was chronic: after more than 10 years, systemic symptoms were not present. In patient No. 1, a monoclonal T-cell population was detected 12 years after the onset of the disease. Both patients had close contact with fertilizers and insecticides. In patient No. 2, the lesions spontaneously regressed within 3 years after cessation of exposure. PV may be a prelymphomatous stage of mycosis fungoides or some closely related cutaneous T-cell lymphoma and does not always evolve into overt malignancy. Gene rearrangement detection techniques may be helpful in predicting the course of the disease.
Related Concept Videos
Background and Environment Affect Phenotype
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
Nucleotide Excision Repair
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Nucleotide Excision Repair
Skin Diseases and Disorders
Gram-positive Staphylococcus spp. and Streptococcus spp. are responsible for many of the most common skin infections. However, many...
Epistasis
Pigmentation
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...