Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
18 result(s) for "Pousada, Guillermo"
Sort by:
Characterization of rare ABCC8 variants identified in Spanish pulmonary arterial hypertension patients
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.
Efficacy and Safety of Two-Drug Regimens with Dolutegravir plus Rilpivirine or Lamivudine in HIV-1 Virologically Suppressed People Living with HIV
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.
Novel Mutations in BMPR2, ACVRL1 and KCNA5 Genes and Hemodynamic Parameters in Patients with Pulmonary Arterial Hypertension
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.
Molecular and functional characterization of the BMPR2 gene in Pulmonary Arterial Hypertension
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.
Dolutegravir Plus 3TC in Virologically Suppressed PLWHIV: Immunological Outcomes in a Multicenter Retrospective Cohort in Spain during the COVID-19 Pandemic
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.
Functional analysis by minigene assay of putative splicing variants found in Bardet–Biedl syndrome patients
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.
Complex inheritance in Pulmonary Arterial Hypertension patients with several mutations
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.
Molecular and clinical analysis of TRPC6 and AGTR1 genes in patients with pulmonary arterial hypertension
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.
Impact of the initial administration of an antiretroviral drug with latency reversal properties on the HIV reservoir size
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.