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HIV-1 non-B subtype infections have been observed in Belgium since the 1980s. However, subtype B predominates amongst men having sex with men (MSM), whereas other subtypes are mainly associated with sub-Saharan African migrants and heterosexual risk behavior. In the last decade, subtype F1 diagnoses have increased substantially in Belgium, representing 9% of newly diagnosed and therapy-naïve HIV-1 patients linked to care in 2014. In the present study, the Belgian subtype F1 epidemic has been characterized within a global context, where F1 is responsible for

Background: CD4 cell recovery following first-line combination ART (cART) is poorer in HIV-2+ than in HIV-1+ patients. Only large comparisons may allow adjustments for demographic and pretreatment plasma viral load (pVL). Methods: ART-naive HIV+ adults from two European multicohort collaborations, COHERE (HIV-1 alone) and ACHIeV2e (HIV-2 alone), were included, if they started first-line cART (without NNRTIs or fusion inhibitors) between 1997 and 2011. Patients without at least one CD4 cell count before start of cART, without a pretreatment pVL and with missing a priori-defined covariables were excluded. Evolution of CD4 cell count was studied using adjusted linear mixed models. Results: We included 185 HIV-2+ and 30321 HIV-1+ patients with median age of 46 years (IQR 36-52) and 37 years (IQR 31-44), respectively. Median observed pretreatment CD4 cell counts/mm3 were 203 (95% CI 100-290) in HIV-2+ patients and 223 (95% CI 100-353) in HIV-1+ patients. Mean observed CD4 cell count changes from start of cART to 12months were +105 (95% CI 77-134) in HIV-2+ patients and +202 (95% CI 199-205) in HIV-1+ patients, an observed difference of 97 cells/mm3 in 1 year. In adjusted analysis, the mean CD4 cell increase was overall 25 CD4 cells/mm3/year lower (95% CI 5-44; P=0.0127) in HIV-2+ patients compared with HIV-1+ patients. Conclusions: A poorer CD4 cell increase during first-line cART was observed in HIV-2+patients, even after adjusting for pretreatment pVL and other potential confounders. Our results underline the need to identify more potent therapeutic regimens or strategies against HIV-2.

In 2011, a consensus was reached defining "late presenters" (LPs) as individuals presenting for care with a CD4 count, SCOPUS: ar.j, FLWOA, info:eu-repo/semantics/published

The Belgian HIV epidemic is largely concentrated among men who have sex with men and Sub-Saharan Africans. We studied the continuum of HIV care of those diagnosed with HIV living in Belgium and its associated factors., SCOPUS: ar.j, info:eu-repo/semantics/published

Contains fulltext : 97014.pdf (Publisher’s version ) (Open Access) BACKGROUND: Triple nucleoside reverse-transcriptase inhibitors (NRTIs) are recommended by the World Health Organization as first-line regimen in treatment-naive HIV-2-infected patients. However, ritonavir-boosted protease inhibitor (PI/r)-containing regimens are frequently prescribed. In the absence of previous randomized trials, we retrospectively compared these regimens in observational cohorts. METHODS: HIV-2-infected patients from 7 European cohorts who started triple NRTI or PI/r since January 1998 were included. Piecewise linear models were used to estimate CD4 cell count and plasma HIV-2 RNA level slopes, differentiating an early phase (until end of month 3) and a second phase (months 4-12). On-treatment analyses censored data at major treatment modification and systematically at month 12. RESULTS: Forty-four patients started triple NRTI therapy and 126 started PI/r therapy. Overall, the median CD4 cell count was 191 cells/mm(3) and the median plasma HIV-2 RNA level was >/=2.7 log(10) copies/ml in 61% of the patients at combination antiretroviral therapy (cART) initiation; the median duration of the first cART was 20 months, not differing between groups. PI/r regimens were associated with better CD4 cell count and HIV-2 RNA level outcomes, compared with NRTI regimens. Estimated CD4 cell count slopes were +6 and +12 cells/mm(3)/month during the early phase (P = .22), and -60 cells/mm(3)/year versus +76 cells/mm(3)/year during the second phase (P = .002), for triple NRTI and PI/r, respectively. Estimated mean HIV-2 RNA levels at month 12 in patients with detectable viremia at cART initiation were 4.0 and 2.2 log(10) copies/ml, respectively (P = .005). CONCLUSIONS: In this observational study, PI/r-containing regimens showed superior efficacy over triple NRTI regimens as first-line therapy in HIV-2-infected patients.

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Wood samples were taken from the upper and lower sides of 21 naturally tilted trees from 18 families of angiosperms in the tropical rain forest in French Guyana. The measurement of growth stresses ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile stressed wood on the upper side, called tension wood, and lower tensile stressed wood on the lower side, called opposite wood. Eight species had tension wood fibres with a distinct gelatinous layer (G-layer). The distribution of gelatinous fibres varied from species to species. One of the species, Casearia javitensis (Flacourtiaceae), showed a peculiar multilayered secondary wall in its reaction wood. Comparison between the stress level and the occurrence of the G-layer indicates that the G-layer is not a key factor in the production of high tensile stressed wood.

International audience; The anatomy of tension wood and opposite wood was compared in 21 tropical rain forest trees from 21 species belonging to 18 families from French Guyana. Wood secimens were taken from the upper and lower sides of naturally titled trees. Measurement of the growth stress level ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile-stressed wood on the upper side, called tension wood and normally tensile-stressed wood on the lower side, called opposite wood. Quantitative parameters relating to fibres and vessels were measured on transverse sections of both tension and opposite wood to check if certain criteria can easily discriminate the two kinds of wood. We observed a decrease in the frequency of vessels in the tension wood in all the trees studied. Other criteria concerning shape and surface area of the vessels, fibre diameter or cell wall thickness did not reveal any general trend.At the ultrastructural level, we observed that the microfibril angle in the tension wood sample was lower than in opposite wood in all the trees except one (Licania membranacea).

Tension wood is known to be the main mechanism for the shape control in angiosperms. An overview of the anatomical diversity of tension wood by comparison to opposite wood is presented from the result of a study on 21 species in tropical rain forest. Anatomical measurements on vessel and fibres do not allow to evidence common criteria for the high tensile stress generation. At the ultrastructural level, microfibrils angle is the only common criterion with a lower MFA in tension wood. Typical gelatinous (G-) layer appears to be present in few species only, some other species present an intermediary stage of modification between S2 and G and in some other, fibres do not present any anatomical difference between normal and tension wood. Typical gelatinous fibres do not show any evidence of producing a higher stress level than other types of tension wood. From this study, it appears that residual tension strains reach a maximum around 3500 µstrain. The presence of a maximum is discussed; it can be interpreted either as a physical limit in the mechanism generating maturation stress or as a trade-off in order prevent the stem from internal cracks. To increase the bending moment the role of opposite wood has to be taken into account. It can be observed some very low tensile stress value and sometime compression stress value on the opposite side of tension wood. Measurement of physical properties such as longitudinal shrinkage or ultrastructural features such as MFA have been done in order to prove that these compression values in angiosperms are not artefacts. Finally, few words are presented on another complementary mechanism: the growth eccentricity with the extreme case of buttresses of tropical rain forest trees.