Temporary redundant transmission mechanism for SCTP multihomed hosts.
Ontology highlight
ABSTRACT:
SUBMITTER: Geetha DM
PROVIDER: S-EPMC4313524 | biostudies-other | 2015
REPOSITORIES: biostudies-other
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Project description:The flatworm Macrostomum lignano features a duo-gland adhesive system that allows it to repeatedly attach to and release from substrates in seawater within a minute. However, little is known about the molecules involved in this temporary adhesion. In this study, we showed that the attachment of M. lignano relieds on the secretion of two large adhesive proteins, Macrostomum lignano adhesion protein 1 (Mlig-ap1) and Mlig-ap2. We revealed that both proteins are expressed in the adhesive gland cells and that their distribution within the adhesive footprints was spatially restricted. RNA interference knock-down experiments demonstrated the essential function of these two proteins in flatworm adhesion. Negatively-charged modified sugars in the surrounding water inhibited flatworm attachment, while positively-charged molecules impeded detachment. In addition, we found that M. lignano could not adhere to strongly hydrated surfaces. We propose an attachment-release model where Mlig-ap2 attaches to the substrate and Mlig-ap1 exhibits a cohesive function. A small negatively-charged molecule is secreted that interferes with Mlig-ap1, inducing detachment. These findings are of relevance for fundamental adhesion science and efforts to mitigate biofouling. Further, this first model of flatworm temporary adhesion may serve as the starting point for the development of synthetic reversible adhesion systems for medicinal and industrial applications.
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Project description:Background The aim of this study is to estimate the reduction in new HIV infections and resultant cost outcomes of providing antiretroviral treatment (ART) through Australia's 'universal access' health scheme to all temporary residents with HIV infection living legally in Australia, but currently deemed ineligible to access subsidised ART via this scheme. METHODS:A mathematical model to estimate the number of new HIV infections averted and the associated lifetime costs over 5 years if all HIV-positive temporary residents in Australia had access to ART and subsidised medical care was developed. Input data came from a cohort of 180 HIV-positive temporary residents living in Australia who are receiving free ART donated by pharmaceutical companies for up to 4 years. RESULTS:Expanding ART access to an estimated total 450 HIV+ temporary residents in Australia for 5 years could avert 80 new infections. The model estimated the total median discounted (5%) cost for ART and associated care to be A$36million, while the total savings in lifetime-discounted costs for the new infections averted was A$22million. CONCLUSIONS:It is estimated that expanded access to ART for all HIV-positive temporary residents in Australia will substantially reduce HIV transmission to their sexual partners at little additional cost. In the context of Australia's National HIV strategy and Australia's endorsement of global goals to provide universal access to ART for all people with HIV, this is an important measure to remove inequities in the provision of HIV-related treatment and care.
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