China
Africa
Explore chapters and articles related to this topic
Cutaneous Neoplastic Manifestations of HIV Disease
Published in Clay J. Cockerell, Antoanella Calame, Cutaneous Manifestations of HIV Disease, 2012
Cindy Berthelot, Clay J. Cockerell
The search for an infectious agent was initiated by Giraldo and coworkers who observed herpes-like particles in cell cultures from classic and endemic KS.7 They also found a serologic association between cytomegalovirus (CMV) and classic endemic KS. During the outbreak of the AIDS epidemic and the increase in KS patients, isolated reports appeared that suggested Mycoplasma penetrans, hepatitis B virus, and human papilloma virus (HPV) as possible causal agents of KS.8 In 1994, Chang et al. identified deoxyribonucleic acid (DNA) sequences in AIDS-KS coding for amino acids that shared striking homology (30–50%) with two oncogenic gamma-herpesviruses: herpesvirus saimiri and Epstein–Barr virus (EBV).9 These findings suggested that a new herpesvirus, designated as human herpesvirus type 8 (HHV-8) or KS-associated herpesvirus (KSHV) could possibly be the causative agent of KS. In addition, it is the only virus of the genus Rhadinovirus known to infect human beings.
Nuclease activity: an exploitable biomarker in bacterial infections
Published in Expert Review of Molecular Diagnostics, 2022
Javier Garcia Gonzalez, Frank J. Hernandez
In fact, recent studies have identified membrane-associated extracellular nucleases in Mycoplasma meleagridis (Mm19) [83] and Mycoplasma hyopneumoniae (mhp379) [84], common animal pathogens, as well as in species isolated from humans, such as Mycoplasma pneumoniae (M. pneumoniae) (Mpn133) [85], Mycoplasma genitalium (MG-168) [86] or Mycoplasma penetrans (P40) [87,88]. Interestingly, mhp379, MG-168 and Mpn133 are Ca2+-dependent nuclease homologues with broad substrate specificity belonging to the MN cluster of orthologous proteins (COG1525) that are encoded upstream of genes encoding for homologous ABC transport systems, which is in line with the previously proposed nutrient scavenging roles of mycoplasma nucleases [28]. This hypothesis is further supported by the ability of other mycoplasmas to use undegraded DNA and RNA as a nutrient source [89] and the observed reduction of the cytotoxic effects of M. pneumoniae in the presence of adenine supplement [90]. However, their ability to induce internucleosomal DNA degradation [86,91,92] and observations in in vitro models of human-derived cell of membrane binding, internalization, reduction of viability and induction of apoptosis [85,88], also suggest a role of mycoplasmas´ extracellular nucleases as pathogenic determinants.