Background: Lopinavir/ritonavir is a protease inhibitor (PI) that has shown great effectiveness as salvage therapy in PI-experienced HIV-infected children. Objectives: To study whether mutations in ...the HIV-1 protease gene can reliably predict virological responses to salvage therapy with lopinavir/ritonavir in HIV-infected children. Patients and methods: We carried out a prospective study in 56 HIV-infected children. PI-associated resistance mutations were determined by genotypic testing and were scored according to the IAS-USA guidelines 2005. Results: Children with a ‘lopinavir mutation score’ (LMS) ≥6 had a negative association for achieving viral load (VL) control undetectable viral load (uVL) ≤400 copies/mL and maintaining uVL for at least 6 months. Moreover, children with protease-associated mutations (PRAMs) ≥2 had a negative association for achieving VL control but not for maintaining uVL for at least 6 months. The relative proportion (RP) to uVL was 0.32 (CI95%: 0.16; 0.33; P = 0.002) in children with I54V (46% of total) and 0.48 (CI95%: 0.24; 0.97; P = 0.041) in children with V82A/F (52% of total). Children with I54V and V82A/F had higher prevalence of lopinavir-associated resistance mutations and showed RP of 0.36 (CI95%: 0.17; 0.76; P = 0.007) for achieving uVL. Conclusions: LMS and PRAMs in HIV-infected children were associated with virological failure in pre-treated HIV-infected children on salvage therapy with lopinavir/ritonavir. Moreover, I54V and V82A/F led to the poorest virological response.
To update antiretroviral recommendations in antiretroviral therapy (ART) in HIV-infected children and adolescents.
Theses guidelines have been formulated by a panel of members of the Plan Nacional ...sobre el SIDA (PNS) and the Asociacion Espanola de Pediatria (AEP) by reviewing the current available evidence of efficacy, safety, and pharmacokinetics in pediatric studies. Three levels of evidence have been defined according to the source of data: Level A: randomized and controlled studies; Level B: Cohort and case-control studies; Level C: Descriptive studies and experts' opinion.
When to start ART should be made on an individual basis, discussed with the family, considering the risk of progression according to age, CD4 and viral load, the ART-related complications and adherence. The ART goal is to reach a maximum and durable viral suppression. This is not always possible, even with clinical and immunologic improvement. The difficulties of permanent adherence and side-effects are resulting in a more conservative trend to initiate ART, and to less toxic and simpler strategies. Currently, combinations of at least three drugs are of first choice both in acute and chronic infection. They must include 2 NA 1 1 NN or 2 NA 1 1 PI. ART is recommended in all symptomatic patients and, with few exceptions, in all infants in the first year of life. Older asymptomatic children should start ART according to CD4 count, especially CD4 percentage, that vary with age. Despite potent salvage therapies, it is common not to reach viral undetectability. Therapeutical options when ART fails are scarce due to cross-resistance. The cause of failure must be identified. Occasionally, there exists clinical and/or immunological progression, and a change of therapy with at least two new drugs still active for the patient, is warranted with the aim of increasing the CD4 count to a lower level of risk. Toxicity and adherence must be regularly monitored. Some aspects about post exposure prophylaxis and coinfection with HCV or HBV are discussed.
A higher level of evidence with regard to ART effectiveness and toxicity in pediatrics is currently available, leading to a more conservative and individualized approach. Clinical symptoms and CD4 count are the main determinants to start and change ART.
We present the Lyman-\(a\) (Lya) Luminosity Function (LF) at \(2.05<z<3.75\), estimated from a sample of 67 Lya-emitter (LAE) candidates in the J-PAS Pathfinder surveys: miniJPAS and J-NEP. These two ...surveys cover a total effective area of \(\sim 1.14\) deg\(^2\) with 54 Narrow Band (NB) filters across the optical range, with typical limiting magnitudes of \(\sim 23\). This set of NBs allows to probe Lya emission in a wide and continuous range of redshifts. We develop a method for detecting Lya emission for the estimation of the Lya LF using the whole J-PAS filter set. We test this method by applying it to the miniJPAS and J-NEP data. In order to compute the corrections needed to estimate the Lya LF and to test the performance of the candidates selection method, we build mock catalogs. These include representative populations of Lya Emitters at \(1.9<z<4.5\) as well as their expected contaminants, namely low-\(z\) galaxies and \(z<2\) QSOs. We show that our method is able to provide the Lya LF at the intermediate-bright range of luminosity (\(\rm 10^{43.5} erg\,s^{-1} \lesssim L_{Lya} \lesssim 10^{44.5} erg\,s^{-1}\)). The photometric information provided by these surveys suggests that our samples are dominated by bright, Lya-emitting Active Galactic Nuclei. At \(L_{{\rm Ly}a}<10^{44.5}\) erg\,s\(^{-1}\), we fit our Lya LF to a power-law with slope \(A=0.70\pm0.25\). We also fit a Schechter function to our data, obtaining: Log\((\Phi^* / \text{Mpc\)^{-3}\(})=-6.30^{+0.48}_{-0.70}\), Log\((L^*/ \rm erg\,s^{-1})=44.85^{+0.50}_{-0.32}\), \(a=-1.65^{+0.29}_{-0.27}\). Overall, our results confirm the presence of an AGN component at the bright-end of the Lya LF. In particular, we find no significant contribution of star-forming LAEs to the Lya LF at Log\((L_{\rm Lya}\) / erg s\(^{-1}\))>43.5. This work serves as a proof-of-concept for the results that can be obtained with the upcoming data releases of the J-PAS survey.
We present ELDAR, a new method that exploits the potential of medium- and narrow-band filter surveys to securely identify active galactic nuclei (AGN) and determine their redshifts. Our methodology ...improves on traditional approaches by looking for AGN emission lines expected to be identified against the continuum, thanks to the width of the filters. To assess its performance, we apply ELDAR to the data of the ALHAMBRA survey, which covered an effective area of \(2.38\,{\rm deg}^2\) with 20 contiguous medium-band optical filters down to F814W\(\simeq 24.5\). Using two different configurations of ELDAR in which we require the detection of at least 2 and 3 emission lines, respectively, we extract two catalogues of type-I AGN. The first is composed of 585 sources (\(79\,\%\) of them spectroscopically-unknown) down to F814W\(=22.5\) at \(z_{\rm phot}>1\), which corresponds to a surface density of \(209\,{\rm deg}^{-2}\). In the second, the 494 selected sources (\(83\,\%\) of them spectroscopically-unknown) reach F814W\(=23\) at \(z_{\rm phot}>1.5\), for a corresponding number density of \(176\,{\rm deg}^{-2}\). Then, using samples of spectroscopically-known AGN in the ALHAMBRA fields, for the two catalogues we estimate a completeness of \(73\,\%\) and \(67\,\%\), and a redshift precision of \(1.01\,\%\) and \(0.86\,\%\) (with outliers fractions of \(8.1\,\%\) and \(5.8\,\%\)). At \(z>2\), where our selection performs best, we reach \(85\,\%\) and \(77\,\%\) completeness and we find no contamination from galaxies.
We present a catalogue of 348 galaxy clusters and groups with \(0.2<z<1.2\) selected in the 2.78 \(deg^2\) ALHAMBRA Survey. The high precision of our photometric redshifts, close to \(1\%\), and the ...wide spread of the seven ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and is less affected by cosmic variance than comparable samples. The detection has been carried out with the Bayesian Cluster Finder (BCF), whose performance has been checked in ALHAMBRA-like light-cone mock catalogues. Great care has been taken to ensure that the observable properties of the mocks photometry accurately correspond to those of real catalogues. From our simulations, we expect to detect galaxy clusters and groups with both \(70\%\) completeness and purity down to dark matter halo masses of \(M_h\sim3\times10^{13}\rm M_{\odot}\) for \(z<0.85\). Cluster redshifts are expected to be recovered with \(\sim0.6\%\) precision for \(z<1\). We also expect to measure cluster masses with \(\sigma_{M_h|M^*_{CL}}\sim0.25-0.35\, dex\) precision down to \(\sim3\times10^{13}\rm M_{\odot}\), masses which are \(50\%\) smaller than those reached by similar work. We have compared these detections with previous optical, spectroscopic and X-rays work, finding an excellent agreement with the rates reported from the simulations. We have also explored the overall properties of these detections such as the presence of a colour-magnitude relation, the evolution of the photometric blue fraction and the clustering of these sources in the different ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that, for a fixed stellar mass, the environment is playing a crucial role at lower redshifts (z\(<\)0.5).
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