Global trends in molecular epidemiology of HIV-1 during 2000-2007

Objective To estimate the global and regional distribution of HIV-1 subtypes and recombinants between 2000 and 2007. Design Country-specific HIV-1 molecular epidemiology data were combined with estimates of the number of HIV-infected people in each country. Method Cross-sectional HIV-1 subtyping data were collected from 65913 samples in 109 countries between 2000 and 2007. The distribution of HIV-1 subtypes in individual countries was weighted according to the number of HIV-infected people in each country to generate estimates of regional and global HIV-1 subtype distribution for the periods 2000–2003 and 2004–2007. Results Analysis of the global distribution of HIV-1 subtypes and recombinants in the two time periods indicated a broadly stable distribution of HIV-1 subtypes worldwide with a notable increase in the proportion of circulating recombinant forms (CRFs), a decrease in unique recombinant forms (URFs), and an overall increase in recombinants. In 2004–2007, subtype C accounted for nearly half (48%) of all global infections, followed by subtypes A (12%) and B (11%), CRF02_AG (8%), CRF01_AE (5%), subtype G (5%) and D(2%). Subtypes F, H, J and K together cause fewer than 1% of infections worldwide. Other CRFs and URFs are each responsible for 4% of global infections, bringing the combined total of worldwide CRFs to 16% and all recombinants (CRFs plus URFs) to 20%. Conclusions The global and regional distributions of individual subtypes and recombinants are broadly stable, although CRFs may play an increasing role in the HIV pandemic. The global diversity of HIV-1 poses a formidable challenge to HIV vaccine development.Fil: Hemelaar, Joris. University of Oxford; Reino UnidoFil: Gouwsb, Eleanor. UNAIDS; SuizaFil: Ghysb, Peter D.. UNAIDS; SuizaFil: Osmanov, Saladin. WHO-UNAIDS HIV Vaccine Initiative; SuizaFil: WHO-UNAIDS Network for HIV Isolation and Characterisation.Fil: Salomon, Horacio Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentin

Ensuring quality: a key consideration in scaling-up HIV-related point-of-care testing programs.

OBJECTIVE: The objective of the WHO/US President's Emergency Plan for AIDS Relief consultation was to discuss innovative strategies, offer guidance, and develop a comprehensive policy framework for implementing quality-assured HIV-related point-of-care testing (POCT). METHODS: The consultation was attended by representatives from international agencies (WHO, UNICEF, UNITAID, Clinton Health Access Initiative), United States Agency for International Development, Centers for Disease Control and Prevention/President's Emergency Plan for AIDS Relief Cooperative Agreement Partners, and experts from more than 25 countries, including policy makers, clinicians, laboratory experts, and program implementers. MAIN OUTCOMES: There was strong consensus among all participants that ensuring access to quality of POCT represents one of the key challenges for the success of HIV prevention, treatment, and care programs. The following four strategies were recommended: implement a newly proposed concept of a sustainable quality assurance cycle that includes careful planning; definition of goals and targets; timely implementation; continuous monitoring; improvements and adjustments, where necessary; and a detailed evaluation; the importance of supporting a cadre of workers [e.g. volunteer quality corps (Q-Corps)] with the role to ensure that the quality assurance cycle is followed and sustained; implementation of the new strategy should be seen as a step-wise process, supported by development of appropriate policies and tools; and joint partnership under the leadership of the ministries of health to ensure sustainability of implementing novel approaches. CONCLUSION: The outcomes of this consultation have been well received by program implementers in the field. The recommendations also laid the groundwork for developing key policy and quality documents for the implementation of HIV-related POCT

Rapport suisse

Saladin Peter. Rapport suisse. In: Annuaire international de justice constitutionnelle, 7-1991, 1993. Cours constitutionnelles européennes et droits fondamentaux (nouveau bilan : 1981-1991) pp. 149-158

Le référendum populaire en Suisse

Saladin Peter. Le référendum populaire en Suisse. In: Revue internationale de droit comparé. Vol. 28 N°2, Avril-juin 1976. pp. 331-347

CXCL12 receptor preference, signal transduction, biological response and the expression of 5T4 oncofoetal glycoprotein

CXCL12 is a pleiotropic chemokine capable of eliciting multiple signal transduction cascades and functions, via interaction with either CXCR4 or CXCR7. Factors that determine CXCL12 receptor preference, intracellular signalling route and biological response are poorly understood but are of central importance in the context of therapeutic intervention of the CXCL12 axis in multiple disease states. We have recently demonstrated that 5T4 oncofoetal glycoprotein facilitates functional CXCR4 expression leading to CXCL12 mediated chemotaxis in mouse embryonic cells. Using wild type (WT) and 5T4 knockout (5T4KO) murine embryonic fibroblasts (MEFs), we now show that CXCL12 binding to CXCR4 activates both the ERK and AKT pathways within minutes, but while these pathways are intact they are non-functional in 5T4KO cells treated with CXCL12. Importantly, in the absence of 5T4 expression, CXCR7 is upregulated and becomes the predominant receptor for CXCL12, activating a distinct signal transduction pathway with slower kinetics involving transactivation of the EGFR, eliciting proliferation rather than chemotaxis. Thus the surface expression of 5T4 marks the use of the CXCR4 rather than the CXCR7 receptor, with distinct consequences for CXCL12 exposure, relevant to the spread and growth of a tumour. Consistent with this hypothesis we have identified human small cell lung carcinoma cells with similar 5T4/CXCR7 reciprocity that is predictive of biological response to CXCL12 and determined that 5T4 expression is required for functional chemotaxis in these cells.</jats:p