Exploring the association between erythema multiforme and HIV infection: some mechanisms and implications.

Erythema multiforme (EM) is an immune-mediated mucocutaneous condition characterized by hypersensitivity reactions to antigenic stimuli from infectious agents and certain drugs. The most commonly implicated infectious agents associated with EM include herpes simplex virus (HSV) and Mycoplasma pneumoniae. Other infectious diseases reported to trigger EM include human immunodeficiency virus (HIV) infection and several opportunistic infections. However, studies focusing on EM and human immunodeficiency virus (HIV) infection are scarce. even though the incidence of EM among HIV-infected individuals have increased, the direct and indirect mechanisms that predispose HIV-infected individuals to EM are not well understood. In turn, this makes diagnosing and managing EM in HIV-infected individuals an overwhelming task. Individuals with HIV infection are prone to acquiring microorganisms known to trigger EM, such as HSV, Mycobacterium tuberculosis, Treponema pallidum, histoplasmosis, and many other infectious organisms. Although HIV is known to infect CD4 + T cells, it can also directly bind to the epithelial cells of the oral and genital mucosa, leading to a dysregulated response by CD8 + T cells against epithelial cells. HIV infection may also trigger EM directly when CD8 + T cells recognize viral particles on epithelial cells due to the hyperactivation of CD8 + T-cells. The hyperactivation of CD8 + T cells was similar to that observed in drug hypersensitivity reactions. Hence, the relationship between antiretroviral drugs and EM has been well established. This includes the administration of other drugs to HIV-infected individuals to manage opportunistic infections. Thus, multiple triggers may be present simultaneously in HIV-infected individuals. This article highlights the potential direct and indirect role that HIV infection may play in the development of EM and the clinical dilemma that arises in the management of HIV-infected patients with this condition. These patients may require additional medications to manage opportunistic infections, many of which can also trigger hypersensitivity reactions leading to EM.

Tumour Genetic Heterogeneity in Relation to Oral Squamous Cell Carcinoma and Anti-Cancer Treatment.

Oral squamous cell carcinoma (SCC) represents more than 90% of all oral cancers and is the most frequent SCC of the head and neck region. It may affect any oral mucosal subsite but most frequently the tongue, followed by the floor of the mouth. The use of tobacco and betel nut, either smoked or chewed, and abuse of alcohol are the main risk factors for oral SCC. Oral SCC is characterized by considerable genetic heterogeneity and diversity, which together have a significant impact on the biological behaviour, clinical course, and response to treatment and on the generally poor prognosis of this carcinoma. Characterization of spatial and temporal tumour-specific molecular profiles and of person-specific resource availability and environmental and biological selective pressures could assist in personalizing anti-cancer treatment for individual patients, with the aim of improving treatment outcomes. In this narrative review, we discuss some of the events in cancer evolution and the functional significance of driver-mutations in carcinoma-related genes in general and elaborate on mechanisms mediating resistance to anti-cancer treatment.

A micro-CT study of the greater palatine foramen in human skulls.

The greater palatine foramen (GPF) is an important anatomical landmark and has substantial clinical relevance in dental surgery. Knowledge of its precise location and dimensions is required for proper planning of surgical procedures involving the posterior maxilla. We used microfocus computed tomography to determine the location and dimensions of the GPF, and any sex and race variations in those measurements, in 77 human skulls scanned at the South African Nuclear Energy Corporation. Specialized software was used for three-dimensional rendering, segmentation, and visualization of the reconstructed volume data. GPF location ranged from adjacent to the first molar to distal of the third molar. The most common GPF location was near the third molar (66.7% of skulls), and the GPF was as close as 6.31 mm (mean distance 12.75 ± 3 mm). The mean GPF dimensions were 5.22 mm on the anterior-posterior axis and 2.81 mm on the lateral-medial axis. We noted no significant differences in relation to race, sex, or age in the sample. The GPF was adjacent or posterior to the third maxillary molar in most skulls.