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18
result(s) for
"Pousada, Guillermo"
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Characterization of rare ABCC8 variants identified in Spanish pulmonary arterial hypertension patients
by
Baloira, Adolfo
,
Lapunzina, Pablo
,
Pérez-Olivares, Carmen
in
631/208/200
,
631/208/737
,
692/4019/592
2020
Pulmonary Arterial Hypertension (PAH) is a rare and fatal disease where knowledge about its genetic basis continues to increase. In this study, we used targeted panel sequencing in a cohort of 624 adult and pediatric patients from the Spanish PAH registry. We identified 11 rare variants in the ATP-binding Cassette subfamily C member 8 (
ABCC8
) gene, most of them with splicing alteration predictions. One patient also carried another variant in
SMAD1
gene (c.27delinsGTAAAG). We performed an
ABCC8
in vitro biochemical analyses using hybrid minigenes to confirm the correct mRNA processing of 3 missense variants (c.211C > T p.His71Tyr, c.298G > A p.Glu100Lys and c.1429G > A p.Val477Met) and the skipping of exon 27 in the novel splicing variant c.3394G > A. Finally, we used structural protein information to further assess the pathogenicity of the variants. The results showed 11 novel changes in
ABCC8
and 1 in
SMAD1
present in PAH patients. After in silico and in vitro biochemical analyses, we classified 2 as pathogenic (c.3288_3289del and c.3394G > A), 6 as likely pathogenic (c.211C > T, c.1429G > A, c.1643C > T, c.2422C > A, c.2694 + 1G > A, c.3976G > A and
SMAD1
c.27delinsGTAAAG) and 3 as Variants of Uncertain Significance (c.298G > A, c.2176G > A and c.3238G > A). In all, we show that coupling in silico tools with in vitro biochemical studies can improve the classification of genetic variants.
Journal Article
Efficacy and Safety of Two-Drug Regimens with Dolutegravir plus Rilpivirine or Lamivudine in HIV-1 Virologically Suppressed People Living with HIV
by
Iribarren, José A.
,
Troya, Jesús
,
Buzón, Luis
in
Acquired immune deficiency syndrome
,
AIDS
,
Anti-HIV Agents - adverse effects
2023
Background: The high effectiveness and safety of the two-drug (2DRs) strategy using dolutegravir (DTG) plus lamivudine (3TC) have led to international guidelines recommending their use for treatment-naive HIV patients. In virologically suppressed patients, de-escalating from 3DRs to DTG plus either rilpivirine (RPV) or 3TC has shown high rates of virological suppression. Objectives: This study aimed to compare the real-life data of two multicenter Spanish cohorts of PLWHIV treated with DTG plus 3TC (SPADE-3) or RPV (DORIPEX) as a switch strategy, not only in terms of virological suppression, safety, and durability but also in terms of immune restoration. The primary endpoint was the percentage of patients with virological suppression on DTG plus 3TC and DTG plus RPV at weeks 24 and 48. The secondary outcomes included the proportion of patients who experienced the protocol-defined loss of virological control by week 48; changes in immune status in terms of CD4+ and CD8+ T lymphocyte counts and the CD4+/CD8+ ratio; the rate, incidence, and reasons for discontinuation of treatment over the 48-week study period; and safety profiles at weeks 24 and 48. Methods: We conducted a retrospective, observational, multicenter study of 638 and 943 virologically suppressed HIV-1-infected patients in two cohorts who switched to 2DRs with DTG plus RPV or DTG plus 3TC. Results: The most frequent reasons for starting DTG-based 2DRs were treatment simplification/pill burden or drug decrease. The virological suppression rates were 96.9%, 97.4%, and 99.1% at weeks 24, 48, and 96, respectively. The proportion of patients with virological failure over the 48-week study period was 0.01%. Adverse drug reactions were uncommon. Patients treated with DTG+3TC increased CD4, CD8, and CD4/CD8 parameters at 24 and 48 weeks. Conclusions: We conclude that DTG-based 2DRs (combined with 3TC or RPV) in clinical practice were effective and safe as a switching strategy, with a low VF and high viral suppression rates. Both regimens were well tolerated, and ADR rates were low, including neurotoxicity and induced treatment discontinuations.
Journal Article
Novel Mutations in BMPR2, ACVRL1 and KCNA5 Genes and Hemodynamic Parameters in Patients with Pulmonary Arterial Hypertension
by
Baloira, Adolfo
,
Pousada, Guillermo
,
Cifrian, Jose Manuel
in
Activin
,
Activin Receptors, Type II - genetics
,
Analysis
2014
Pulmonary arterial hypertension (PAH) is a rare and progressive vascular disorder characterized by increased pulmonary vascular resistance and right heart failure. The aim of this study was to analyze the Bone Morphogenetic Protein Receptor 2 (BMPR2), Activin A type II receptor like kinase 1 (ALK1/ACVRL1) and potassium voltage-gated channel, shakerrelated subfamily, member 5 (KCNA5) genes in patients with idiopathic and associated PAH. Correlation among pathogenic mutations and clinical and functional parameters was further analyzed.
Forty one patients and fifty controls were included in this study. Analysis of BMPR2, ACVRL1 and KCNA5 genes was performed by polymerase chain reaction (PCR) and direct sequencing. Fifty one nucleotide changes were detected in these genes in 40 of the 41 patients; only 22 of these changes, which were classified as pathogenic, have been detected in 21 patients (51.2%). Ten patients (62.5%) with idiopathic PAH and 10 (40%) with associated PAH showed pathogenic mutations in some of the three genes. Several clinical and hemodynamics parameters showed significant differences between carriers and non-carriers of mutations, being more severe in carriers: mean pulmonary artery pressure (p = 0.043), pulmonary vascular resistence (p = 0.043), cardiac index (p = 0.04) and 6 minute walking test (p = 0.02). This differences remained unchanged after adjusting for PAH type (idiopathic vs non idiopathic).
Pathogenic mutations in BMPR2 gene are frequent in patients with idiopathic and associated PAH group I. Mutations in ACVRL1 and KCNA5 are less frequent. The presence of these mutations seems to increase the severity of the disease.
Journal Article
Molecular and functional characterization of the BMPR2 gene in Pulmonary Arterial Hypertension
2017
Pulmonary arterial hypertension is a progressive disease that causes the obstruction of precapillary pulmonary arteries and a sustained increase in pulmonary vascular resistance. The aim was to analyze functionally the variants found in the
BMPR2
gene and to establish a genotype-phenotype correlation. mRNA expression studies were performed using
pSPL3
vector, studies of subcellular localization were performed using
pEGFP-N1
vector and luciferase assays were performed using
pGL3-Basic
vector. We have identified 30 variants in the
BMPR2
gene in 27 of 55 patients. In 16 patients we detected pathogenic mutations. Minigene assays revealed that 6 variants (synonymous, missense) result in splicing defect. By immunofluorescence assay, we observed that 4 mutations affect the protein localization. Finally, 4 mutations located in the 5′UTR region showed a decreased transcriptional activity in luciferase assays. Genotype-phenotype correlation, revealed that patients with pathogenic mutations have a more severe phenotype (sPaP p = 0.042, 6MWT p = 0.041), a lower age at diagnosis (p = 0.040) and seemed to have worse response to phosphodiesterase-5-inhibitors (p = 0.010). Our study confirms that
in vitro
expression analysis is a suitable approach in order to investigate the phenotypic consequences of the nucleotide variants, especially in cases where the involved genes have a pattern of expression in tissues of difficult access.
Journal Article
Dolutegravir Plus 3TC in Virologically Suppressed PLWHIV: Immunological Outcomes in a Multicenter Retrospective Cohort in Spain during the COVID-19 Pandemic
by
Buzón, Luis
,
Dueñas, Carlos
,
Moreno, Estela
in
Acquired immune deficiency syndrome
,
AIDS
,
Antigens
2023
Dolutegravir (DTG) based dual therapies for treating PLWHIV are a standard of care nowadays. Switching to DTG and lamivudine (3TC) safety and efficacy were proven in TANGO randomized clinical trial. This multicenter retrospective study included 1032 HIV virologically suppressed patients switching to DTG+3TC from 13 Spanish hospitals. DTG+3TC provided high rates of undetectable viral load over 96%, corresponding to 96.6% (889/921) at 24 weeks, 97.5% (743/763) at 48 weeks, and 98.3% (417/425) at 96 weeks. No significant differences are evident when comparing the total population according to sex, presence of comorbidity, or presence of AIDS. The analysis for paired data showed an increase in CD4+ cell count. A statistically significant increase in CD4+ lymphocyte count was found in those without comorbidities in the three-time series analyzed [average increase at 24 weeks: 48.7 (SD: 215.3) vs. 25.8 (SD: 215.5), p-value = 0.050; a mean increase at 48 weeks: 75.1 (SD: 232.9) vs. 42.3 (SD: 255.6), p-value = 0.003; a mean increase at 96 weeks: 120.1 (SD: 205.0) vs. 63.8 (SD:275.3), p-value = 0.003]. In conclusion, our cohort demonstrates that DTG+3TC is an effective treatment strategy for virologically-suppressed PLWHIV independent of age, sex, and HIV stage, as well as a safe and durable strategy.
Journal Article
Functional analysis by minigene assay of putative splicing variants found in Bardet–Biedl syndrome patients
by
Pousada, Guillermo
,
Álvarez‐Satta, María
,
Castro‐Sánchez, Sheila
in
ADP-Ribosylation Factors - genetics
,
Alternative Splicing
,
Amino acids
2017
Bardet–Biedl syndrome (BBS) and Alström syndrome (ALMS) are rare diseases belonging to the group of ciliopathies. Although mutational screening studies of BBS/ALMS cohorts have been extensively reported, little is known about the functional effect of those changes. Thus, splicing variants are estimated to represent 15% of disease‐causing mutations, and there is growing evidence that many exonic changes are really splicing variants misclassified. In this study, we aimed to analyse for the first time several variants in BBS2, ARL6/BBS3, BBS4 and ALMS1 genes predicted to produce aberrant splicing by minigene assay. We found discordance between bioinformatics analysis and experimental data when comparing wild‐type and mutant constructs. Remarkably, we identified nonsense variants presumably resistant to nonsense‐mediated decay, even when a premature termination codon would be introduced in the second amino acid (p.(G2*) mutation in ARL6/BBS3 gene). As a whole, we report one of the first functional studies of BBS/ALMS1 variants using minigene assay, trying to elucidate their role in disease. Functional studies of variants identified in BBS and ALMS patients are essential for their proper classification and subsequent genetic counselling and could also be the start point for new therapeutic approaches, currently based only on symptomatic treatment.
Journal Article
Complex inheritance in Pulmonary Arterial Hypertension patients with several mutations
2016
Pulmonary Arterial Hypertension (PAH) is a rare and progressive disease with low incidence and prevalence, and elevated mortality. PAH is characterized by increased mean pulmonary artery pressure. The aim of this study was to analyse patients with combined mutations in
BMPR2
,
ACVRL1
,
ENG
and
KCNA5
genes and to establish a genotype-phenotype correlation. Major genes were analysed by polymerase chain reaction (PCR) and direct sequencing. Genotype-phenotype correlation was performed. Fifty-seven (28 idiopathic PAH, 29 associated PAH group I) were included. Several mutations in different genes, classified as pathogenic by
in silico
analysis, were present in 26% of PAH patients. The most commonly involved gene was
BMPR2
(12 patients) followed by
ENG
gene (9 patients).
ACVRL1
and
KCNA5
genes showed very low incidence of mutations (5 and 1 patients, respectively). Genotype-phenotype correlation showed statistically significant differences for gender (p = 0.045), age at diagnosis (p = 0.035), pulmonary vascular resistance (p = 0.030), cardiac index (p = 0.035) and absence of response to treatment (p = 0.011). PAH is consequence of a heterogeneous constellation of genetic arrangements. Patients with several pathogenic mutations seem to display a more severe phenotype.
Journal Article
Molecular and clinical analysis of TRPC6 and AGTR1 genes in patients with pulmonary arterial hypertension
2015
Background
Pulmonary arterial hypertension (PAH) is a rare and progressive vascular disorder characterized by increased pulmonary vascular resistance and right heart failure. The aim of this study was to analyze 5′UTR region in canonical transient receptor potential isoform 6 (
TRPC6
) and 3′UTR region in Angiotensin II type I receptor (
AGTR1
) genes in patients with idiopathic and associated PAH. Correlation among mutations and clinical and functional parameters was further analyzed.
Methods
Analysis of
TRPC6
and
AGTR1
genes was performed by polymerase chain reaction (PCR) and direct sequencing. We used a non-parametric test to determine if significant differences were found between the groups studied and chi-square test to compare clinical and hemodynamic variables among genotypes.
Results
Fifty five patients and fifty two controls were included in this study. We found statistically significant differences for c.1-361A > T (p = 0.0077), c.1-254C > G (p < 0.0001) and c.1-218C > T (p = 0.0021) in
TRPC6
gene and c.1166A > C (p < 0.001) in
AGTR1
gene, between patients and controls. Idiopathic PAH patients (IPAH) and controls presented significant differences for all 3
TRPC6
polymorphisms (p = 0.020), (p = 0.002) and (p = 0.008) respectively, and also showed differences for
AGTR1
gene (p < 0.001). In associated PAH (APAH) patients we found statistical differences for c.1-254C > G (p < 0.001) and c.1-218C > T (p = 0.001) in
TRPC6
gene and c.1166A > C (p = 0.001) in
AGTR1
gene. Several clinical and hemodynamic parameters showed significant differences between carriers and non-carriers of these single nucleotide polymorphisms (SNPs). Nineteen patients were carriers of all 3 SNPs in
TRPC6
gene and presented a more severe phenotype with differences in mean pulmonary arterial pressure (p = 0.016), systolic pulmonary arterial pressure (p = 0.040), cardiac index (p < 0.001) and 6 minute walking test (p = 0.049). 16 of these patients harbored the SNP in
AGTR1
gene. These patients showed differences in age at diagnosis (p = 0.049), mean pulmonary arterial pressure (p = 0.033), cardiac index (p = 0.002) and 6 minute walking test (p = 0.039).
Conclusions
PAH is a rare disease with pulmonary vascular remodeling caused in part by a heterogeneous constellation of genetic arrangements. This study seems to suggest that c.1-361A > T, c.1-254C > G and c.1-218C > T polymorphisms in
TRPC6
gene and c.1166A > C polymorphism in
AGTR1
could have a role in the development of this disease.
Journal Article
Impact of the initial administration of an antiretroviral drug with latency reversal properties on the HIV reservoir size
by
De La Torre Tarazona, Erick
,
Vicens-Artés, Sònia
,
Luna, Laura
in
631/250/255/1901
,
631/250/255/2514
,
631/326/596/1787
2025
The elimination of the latent viral reservoir remains the main barrier in the quest for a cure for people with HIV (PWH). The administration of latency reversal agents (LRA) at antiretroviral treatment (ART) initiation could improve the effectiveness of strategies aimed at HIV remission. This study assessed the impact of maraviroc (MVC), an antiretroviral drug with HIV latency reversal properties, on the viral reservoir size when it is administered at ART initiation. We conducted a longitudinal observational study in PWH initiating ART with a regimen including (MVC-initiation, n = 12) or not including MVC (non-MVC-initiation, n = 22), or switching to an MVC-containing regimen after achieving an undetectable viral load (VL) (MVC-switch, n = 9). The HIV reservoir size was determined via Alu-LTR and Intact Proviral DNA Assay (IPDA) methods, and cell-associated HIV-RNA (ca-HIV-RNA) by nested-qPCR. Comparative analyses employed mixed multivariate linear models. After a median of 90 weeks, the MVC-initiation group showed a greater reduction in integrated and IPDA-total (7.1- and 4.0-fold, respectively), but not IPDA-intact, HIV-DNA reservoir compared to the non-MVC-initiation group. The reductions in integrated, IPDA-total, and IPDA-intact HIV-DNA levels in the MVC-initiation group were also greater compared to the MVC-switch group (from 5.4 to 13.8-fold). Moreover, no significant differences in the HIV transcriptional activity, assessed by ca-HIV-RNA levels or HIV-RNA/HIV-DNA ratios, were observed between the MVC-initiation and non-MVC-initiation groups. In conclusion, starting ART with a drug with HIV latency reversing activity at detectable VL phase may contribute to a greater reduction in the HIV-DNA reservoir. These findings could inform the design of future trials targeting HIV remission via a “kick and kill” strategy.
Journal Article