27 research outputs found
Lymphoproliferative syndromes associated with human herpesvirus-6A and human herpesvirus-6B
Human herpesvirus 6A and 6B (HHV-6A and HHV-6B) have been noted since their discovery for their T-lymphotropism. Although it has proven difficult to determine the extent to which HHV-6A and HHV-6B are involved in the pathogenesis of many diseases, evidence suggests that primary infection and reactivation of both viruses may induce or contribute to the progression of several lymphoproliferative disorders, ranging from benign to malignant and including infectious mononucleosis-like illness, drug induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS), and nodular sclerosis Hodgkin's lymphoma. Herein, we discuss the conditions associated with the lymphoproliferative capacity of HHV-6, as well as the potential mechanisms behind them. Continued exploration on this topic may add to our understanding of the interactions between HHV-6 and the immune system and may open the doors to more accurate diagnosis and treatment of certain lymphoproliferative disorders
Possible chromosomal and germline integration of human herpesvirus 7
Publisher Copyright: © 2017 The Authors. Copyright: Copyright 2017 Elsevier B.V., All rights reserved.Human herpesvirus 7 (HHV-7) is a betaherpesvirus, and is phylogenetically related to both HHV-6A and HHV-6B. The presence of telomeric repeat sequences at both ends of its genome should make it equally likely to integrate into the human telomere as HHV-6. However, numerous studies have failed to detect germline integration of HHV-7, suggesting an important difference between the HHV-6A/-6B and HHV-7 genomes. In search of possible germline integrated HHV-7, we developed a sensitive and quantitative real-time PCR assay and discovered that primers designed against some parts of the HHV-7 genome can frequently miss HHV-7 positive clinical samples even though they work efficiently in cell-culture-derived HHV-7 positive materials. Using a primer pair against the U90 ORF of HHV-7, we identified a possible case of germline integration of HHV-7 with one copy of viral genome per cell in both peripheral blood cells and hair follicles. Chromosomal integration of HHV-7 in these individuals was confirmed by fluorescence in situ hybridization analysis. Germline integration of HHV-7 was further confirmed by detection of ~2.6 copies of HHV-7 in the hair follicles of one of the parents. Our results shed light on the complex nature of the HHV-7 genome in human-derived materials in comparison to cell-culture-derived materials and show the need for stringent criteria in the selection of primers for epidemiological HHV-7 studies.Peer reviewe
K21 compound, a potent antifungal agent: Implications for the treatment of fluconazole-resistant HIV-associated Candida species
Background/objectives: With mucocutaneous candidiasis being highly prevalent in HIV patients, the emergence of fluconazole-resistant Candida species forms a major challenge in treating and eradicating these infections. The objective of this study was to establish the antifungal activity of K21, a membrane-rupturing antimicrobial compound derived from a silica quaternary ammonium compound (SiQAC) with tetraethoxysilane (TEOS).
Methods: The study sample included 81 Candida species of which 9 were type strains and 72 were clinical isolates. Minimum inhibitory concentrations, synergy, fractional inhibitory concentration index (FICI) and time kill assays were determined by broth microdilution. Electron microscopy (EM) was used to determine the qualitative changes brought about after treatment with K21.
Results: K21 inhibited the growth of all fluconazole-resistant and susceptible Candida strains with only 2 hours of exposure required to effectively kill 99.9% of the inoculum, and a definite synergistic effect observed with a combination of K21 and fluconazole. EM demonstrated the presence of two forms of extracellular vesicles indicative of biofilm formation and cell lysis.
Conclusion: The study established the efficacy of K21 as an antifungal agent and with fluconazole-resistant candidiasis on the increase, the development of K21 can provide a promising alternative to combat acquired drug resistance.KHG fiteBac Technology (grant no. TTOC1705-02
Human Herpesvirus 6 and Malignancy: A Review
In order to determine the role of human herpesvirus 6 (HHV-6) in human disease, several confounding factors, including methods of detection, types of controls, and the ubiquitous nature of the virus, must be considered. This is particularly problematic in the case of cancer, in which rates of detection vary greatly among studies. To determine what part, if any, HHV-6 plays in oncogenesis, a review of the literature was performed. There is evidence that HHV-6 is present in certain types of cancer; however, detection of the virus within tumor cells is insufficient for assigning a direct role of HHV-6 in tumorigenesis. Findings supportive of a causal role for a virus in cancer include presence of the virus in a large proportion of cases, presence of the virus in most tumor cells, and virus-induced in-vitro cell transformation. HHV-6, if not directly oncogenic, may act as a contributory factor that indirectly enhances tumor cell growth, in some cases by cooperation with other viruses. Another possibility is that HHV-6 may merely be an opportunistic virus that thrives in the immunodeficient tumor microenvironment. Although many studies have been carried out, it is still premature to definitively implicate HHV-6 in several human cancers. In some instances, evidence suggests that HHV-6 may cooperate with other viruses, including EBV, HPV, and HHV-8, in the development of cancer, and HHV-6 may have a role in such conditions as nodular sclerosis Hodgkin lymphoma, gastrointestinal cancer, glial tumors, and oral cancers. However, further studies will be required to determine the exact contributions of HHV-6 to tumorigenesis
Introduction
General view, looking southeast, showing the west (left) and north (right) enclosure wall; When Egypt became an unofficial British protectorate in the late 19th century, it was decided to construct a dam at Aswan to control the inundation and to create a reserve of water for irrigation. However, the Aswan Dam, completed in 1902, proved inadequate and was replaced by the Aswan High Dam, built with Russian assistance in the 1960s. The consequent creation of Lake Nasser threatened the destruction of numerous ancient monuments, the most important of which were saved by a relocation programme carried out under UNESCO auspices. Relocated temples in the vicinity of Aswan include the Philae temples on Agilqiyya Island and the temples of Kalabsha and Beit el-Wali at New Kalabsha on the lake shore. Source: Grove Art Online; http://www.groveart.com/ (accessed 1/18/2008
LYMPHOPROLIFERATIVE SYNDROMES ASSOCIATED WITH HUMAN HERPESVIRUS-6A AND HUMAN HERPESVIRUS-6B
Cell mediated immunity to meet the avian influenza A (H5N1) challenge
Abstract Avian influenza A subtype H5N1 virus with its recombination potential with the human influenza viruses presents a threat of producing a pandemic. The consensus is that the occurrence of such a pandemic is only a matter of time. This is of great concern, since no effective vaccine is available or can be made before the occurrence of the event. We present arguments for the use of cell mediated immunity for the prevention of the infection as well as for the treatment of infected patients. Transfer factor (TF), an immunomodulator of low molecular weight capable of transferring antigenspecific cell mediated immune information to T-lymphocytes, has been used successfully over the past quarter of a century for treating viral, parasitic, and fungal infections, as well as immunodeficiencies, neoplasias, allergies and autoimmune diseases. Moreover, several observations suggest that it can be utilised for prevention, transferring immunity prior to infection. Because it is derived from lymphocytes of immune donors, it has the potential to answer the challenge of unknown or ill-defined pathogens. Indeed, it is possible to obtain an antigen-specific TF preparation to a new pathogen before its identification. Thus, a specific TF to a new influenza virus can be made swiftly and used for prevention as well as for the treatment of infected patients