Long considered a freewheeling loner, the Trypanosoma brucei parasite responsible for African sleeping sickness has revealed a totally unexpected social side, opening a potential chink in the behavioral armor of this and other supposedly solitary human parasites, according to research presented at the American Society for Cell Biology’s 50th Annual Meeting in Philadelphia. Read More
Author Summary
Understanding of the dynamics and distribution of Leishmania in the human host is fundamental to the targeting of control measures and their evaluation. Amplification of parasite gene sequences in clinical samples from cutaneous leishmaniasis patients has provided evidence of Leishmania in blood, other tissues and sites distinct from the lesion and of persistence of infection after clinical resolution of disease. Read More
Background:
Based on recent studies in Israel demonstrating that attractive toxic sugar bait (ATSB) methods can be used to decimate local anopheline and culicine mosquito populations, an important consideration is whether the same methods can be adapted and improved to attract and kill malaria vectors in Africa. Read More
Author Summary
Spotted fever rickettsioses are endemic diseases known since the beginning of the 21st century. They may be severe, like Rocky Mountain Spotted fever in the Americas, and are always transmitted by the tick bite. In Africa, little is known about the prevalence of these diseases; most available data is from the travelers who felt ill after coming back to Europe and USA. Read More
The HIV-1-specific antibodies PG9 and PG16 show marked cross-isolate neutralization breadth and potency. Antibody neutralization has been shown to be dependent on the presence of N-linked glycosylation at position 160 in gp120. We show here that (i) the loss of several key glycosylation sites in the V1, V2, and V3 loops; (ii) the generation of pseudoviruses in the presence of various glycosidase inhibitors; and (iii) the growth of pseudoviruses in a mutant cell line (GnT1–/–) that alters envelope glycosylation patterns all have significant effects on the sensitivity of virus to neutralization by PG9 and PG16. Read More
Author Summary
Bacterial infections have long been studied using Koch’s postulates wherein the paradigm is that a single clone leads to a given infection. Over the past decade, it has become clear that chronic bacterial infections often do not fit this paradigm. Instead these are associated with the presence of multiple strains or species (polyclonal) of bacteria that are organized into highly structured communities, termed biofilms, which can persist in the body and are recalcitrant to antibiotic treatment. Read More
Author Summary
HIV infection leads to the depletion of CD4+ T cells, the major viral cell target. The destruction of these cells can occur because of cytopathic effect or apoptosis. HIV Tat is one of the proteins that can contribute to the apoptotic process of both infected and uninfected cells, as it is released in the plasma and enter uninfected cells. Tat expression in CD4+ T-cells is linked to increased transcriptional activity of FOXO3a, a factor that targets the transcription of pro-apoptotic genes. The mechanism by which Tat leads to activation apoptotic pathways is by associating with the promoters of the phospatases PTEN and PP2A and by increasing their levels. Read More
Author Summary
Identifying genes essential for survival in the host is fundamental to unraveling the biology of human pathogens and understanding mechanisms of pathogenesis. The protozoan parasite Trypanosoma brucei causes devastating diseases in humans and animals in sub-Saharan Africa, and the publication in 2005 of the genome sequence provided the first glance at the coding potential of this organism. Read More
Author Summary
The Ebola virus (EBOV) is a highly pathogenic virus that infects humans and non-human primates, causing severe disease or death in the majority of these cases. The interaction of this virus with its host on a cellular level is only just beginning to be understood. EBOV, like many viruses, affects the expression or function of several cell surface proteins, including adhesion factors and protein complexes responsible for allowing the immune system to recognize infected cells. Our group and others have previously shown that expression of the main viral glycoprotein of EBOV in cultured cells is sufficient to cause this disruption. Here we have identified the mechanism by which this disruption occurs. Heavily glycosylated domains of the EBOV glycoprotein form a steric shield over proteins at the cell surface. This steric interference blocks the detection of affected surface proteins using antibody reagents, but also has the functional effect of abrogating cell adhesion and preventing interactions with CD8 T cells. The results from this study highlight a novel mechanism for viral disruption of host cell surface protein functions and give insight to interactions between the Ebola virus and its host.
Background:
Two lymphatic filariasis endemic communities Mampong and Hwida in Ghana have been regularly monitored for impact on transmission after annual mass drug administration (MDA) with albendazole and ivermectin. After six MDAs even though the ABR for Mampong was 55883/person/year and that of Hwida was 2494 /person/year, they both had ATPs of 15.21 infective larvae/person/year. Interestingly the human microfilaraemia levels had reduced significantly from 14% to 0% at Mampong and 12% to 3% at Hwida. Read More
It now appears that the malaria mosquito needs more than one family of odor sensors to sniff out its human prey.
That is the implication of new research into the mosquito’s sense of smell published in the Aug. 31 issue of the online, open-access journal Public Library of Science Biology. Read More
Disease Outbreaks
Built on Simply Works Core
Powered by WordPress
Copyright © Mednews Africa
Medical Journals , Latest News, Alerts
Copyright 2002-2012 MednewsAfrica. Creative Commons