| 1. |
|
|
| 2. |
- Lopes, Fatima, et al.
(författare)
-
Identification of novel genetic causes of Rett syndrome-like phenotypes
- 2016
-
Ingår i: Journal of Medical Genetics. - : BMJ. - 0022-2593 .- 1468-6244. ; 53:3, s. 190-199
-
Tidskriftsartikel (refereegranskat)abstract
- Background The aim of this work was to identify new genetic causes of Rett-like phenotypes using array comparative genomic hybridisation and a whole exome sequencing approach. Methods and results We studied a cohort of 19 Portuguese patients (16 girls, 3 boys) with a clinical presentation significantly overlapping Rett syndrome (RTT). Genetic analysis included filtering of the single nucleotide variants and indels with preference for de novo, homozygous/compound heterozygous, or maternally inherited X linked variants. Examination by MRI and muscle biopsies was also performed. Pathogenic genomic imbalances were found in two patients (10.5%): an 18q21.2 deletion encompassing four exons of the TCF4 gene and a mosaic UPD of chromosome 3. Variants in genes previously implicated in neurodevelopmental disorders (NDD) were identified in six patients (32%): de novo variants in EEF1A2, STXBP1 and ZNF238 were found in three patients, maternally inherited X linked variants in SLC35A2, ZFX and SHROOM4 were detected in two male patients and one homozygous variant in EIF2B2 was detected in one patient. Variants were also detected in five novel NDD candidate genes (26%): we identified de novo variants in the RHOBTB2, SMARCA1 and GABBR2 genes; a homozygous variant in EIF4G1; compound heterozygous variant in HTT. Conclusions Network analysis reveals that these genes interact by means of protein interactions with each other and with the known RTT genes. These findings expand the phenotypical spectrum of previously known NDD genes to encompass RTT-like clinical presentations and identify new candidate genes for RTT-like phenotypes.
|
|
| 3. |
|
|
| 4. |
- Mendieta-Leiva, Glenda, et al.
(författare)
-
EpIG-DB: A database of vascular epiphyte assemblages in the Neotropics
- 2020
-
Ingår i: Journal of Vegetation Science. - : Wiley. - 1100-9233 .- 1654-1103. ; 31, s. 518-528
-
Tidskriftsartikel (refereegranskat)abstract
- Vascular epiphytes are a diverse and conspicuous component of biodiversity in tropical and subtropical forests. Yet, the patterns and drivers of epiphyte assemblages are poorly studied in comparison with soil-rooted plants. Current knowledge about diversity patterns of epiphytes mainly stems from local studies or floristic inventories, but this information has not yet been integrated to allow a better understanding of large-scale distribution patterns. EpIG-DB, the first database on epiphyte assemblages at the continental scale, resulted from an exhaustive compilation of published and unpublished inventory data from the Neotropics. The current version of EpIG-DB consists of 463,196 individual epiphytes from 3,005 species, which were collected from a total of 18,148 relevés (host trees and ‘understory’ plots). EpIG-DB reports the occurrence of ‘true’ epiphytes, hemiepiphytes and nomadic vines, including information on their cover, abundance, frequency and biomass. Most records (97%) correspond to sampled host trees, 76% of them aggregated in forest plots. The data is stored in a TURBOVEG database using the most up-to-date checklist of vascular epiphytes. A total of 18 additional fields were created for the standardization of associated data commonly used in epiphyte ecology (e.g. by considering different sampling methods). EpIG-DB currently covers six major biomes across the whole latitudinal range of epiphytes in the Neotropics but welcomes data globally. This novel database provides, for the first time, unique biodiversity data on epiphytes for the Neotropics and unified guidelines for future collection of epiphyte data. EpIG-DB will allow exploration of new ways to study the community ecology and biogeography of vascular epiphytes.
|
|
| 5. |
- Barbosa, Pedro, et al.
(författare)
-
Bariatric Surgery Induces Alterations in the Immune Profile of Peripheral Blood T Cells
- 2024
-
Ingår i: Biomolecules. - : MDPI. - 2218-273X. ; 14:2
-
Tidskriftsartikel (refereegranskat)abstract
- Low-grade inflammation is closely linked to obesity and obesity-related comorbidities; therefore, immune cells have become an important topic in obesity research. Here, we performed a deep phenotypic characterization of circulating T cells in people with obesity, using flow cytometry. Forty-one individuals with obesity (OB) and clinical criteria for bariatric surgery were enrolled in this study. We identified and quantified 44 different circulating T cell subsets and assessed their activation status and the expression of immune-checkpoint molecules, immediately before (T1) and 7-18 months after (T2) the bariatric surgery. Twelve age- and sex-matched healthy individuals (nOB) were also recruited. The OB participants showed higher leukocyte counts and a higher percentage of neutrophils. The percentage of circulating Th1 cells were negatively correlated to HbA1c and insulin levels. OB Th1 cells displayed a higher activation status and lower PD-1 expression. The percentage of Th17 and Th1/17 cells were increased in OB, whereas the CD4+ Tregs' percentage was decreased. Interestingly, a higher proportion of OB CD4+ Tregs were polarized toward Th1- and Th1/17-like cells and expressed higher levels of CCR5. Bariatric surgery induced the recovery of CD4+ Treg cell levels and the expansion and activation of Tfh and B cells. Our results show alterations in the distribution and phenotype of circulating T cells from OB people, including activation markers and immune-checkpoint proteins, demonstrating that different metabolic profiles are associated to distinct immune profiles, and both are modulated by bariatric surgery.
|
|
| 6. |
- Barbosa, Pedro, et al.
(författare)
-
CD8+Treg cells play a role in the obesity-associated insulin resistance
- 2024
-
Ingår i: Life Sciences. - : Elsevier. - 0024-3205 .- 1879-0631. ; 336
-
Tidskriftsartikel (refereegranskat)abstract
- Obesity-related chronic low-grade inflammation may trigger insulin resistance and type 2 diabetes (T2D) development. Cells with regulatory phenotype have been shown to be reduced during obesity, especially CD4+ Treg cells. However, little is known about the CD8+ Treg cells. Therefore, we aim to characterize the CD8+ Treg cells in human peripheral blood and adipose tissue, specifically, to address the effect of obesity and insulin resistance in this regulatory immune cell population. A group of 42 participants with obesity (OB group) were recruited. Fourteen of them were evaluated pre-and post-bariatric surgery. A group of age-and sex-matched healthy volunteers (n = 12) was also recruited (nOB group). CD8+ Treg cell quantification and phenotype were evaluated by flow cytometry, in peripheral blood (PB), subcutaneous (SAT), and visceral adipose tissues (VAT). The OB group displayed a higher percentage of CD8+ Treg cells in PB, compared to the nOB. In addition, they were preferentially polarized into Tc1-and Tc1/17-like CD8+ Treg cells, compared to nOB. Moreover, SAT displayed the highest content of CD8+ Tregs infiltrated, compared to PB or VAT, while CD8+ Tregs infiltrating VAT displayed a higher percentage of cells with Tc1-like phenotype. Participants with pre-diabetes displayed a reduced percentage of TIM-3+CD8+ Tregs in circulation, and PD-1+CD8+ Tregs infiltrated in the VAT. An in-crease in the percentage of circulating Tc1-like CD8+ Treg cells expressing PD-1 was observed post-surgery. In conclusion, obesity induces significant alterations in CD8+ Treg cells, affecting their percentage and phenotype, as well as the expression of important immune regulatory molecules.
|
|
| 7. |
- Barbosa, Pedro M., et al.
(författare)
-
Large Seasonal and Habitat Differences in Methane Ebullition on the Amazon Floodplain
- 2021
-
Ingår i: Journal of Geophysical Research - Biogeosciences. - : American Geophysical Union (AGU). - 2169-8953 .- 2169-8961. ; 126:7
-
Tidskriftsartikel (refereegranskat)abstract
- Tropical floodplains are an important source of methane (CH4) to the atmosphere, and ebullitive fluxes are likely to be important. We report direct measurements of CH4 ebullition in common habitats on the Amazon floodplain over two years based on floating chambers that allowed detection of bubbles, and submerged bubble traps. Ebullition was highly variable in space and time. Of the 840 floating chamber measurements (equivalent to 8,690 min of 10-min deployments), 22% captured bubbles. Ebullitive CH4 fluxes, measured using bubble traps deployed for a total of approximately 230 days, ranged from 0 to 109 mmol CH4 m−2 d−1, with a mean of 4.4 mmol CH4 m−2 d−1. During falling water, a hydroacoustic echosounder detected bubbles in 24% of the 70-m segments over 34 km. Ebullitive flux increased as the water level fell faster during falling water periods. In flooded forests, highest ebullitive fluxes occurred during falling water, while in open water and herbaceous plant habitats, higher ebullitive fluxes were measured during low water periods. The contribution of diffusive plus ebullitive CH4 flux represented by ebullition varied from 1% (high and rising water in open water of the lake) to 93% (falling water in flooded forests) based on bubble traps. Combining ebullitive and diffusive fluxes among habitats in relation to variations in water depth and areal coverage of aquatic habitats provides the basis for improved floodplain-wide estimates of CH4 evasion.Plain Language SummaryMethane is a trace gas that contributes to global warming, and wetlands are major natural sources. High concentrations of methane in sediments can lead to large releases to the atmosphere via bubbling (called ebullition). The Amazon basin is known to be an important source of CH4 to the atmosphere. We measured CH4 ebullition over two years in flooded forest, macrophytes and open water habitats in an Amazon floodplain using floating chambers that allowed detection of bubbles, and bubble traps; we also used hydroacoustics to detect bubbles in the water column. We found high spatial and temporal variability in all habitats, with ebullitive fluxes tending to be higher when water level was low or falling. While ebullition was often the major route of evasion of methane to the atmosphere, it varied from only about 1% to 93% of the diffusive plus ebullitive flux. The episodic nature and spatial variations of ebullition introduce considerable uncertainty in estimates of ebullitive CH4 flux. Our results have important implications for the regionalization of CH4 fluxes for Amazon floodplains and inland waters elsewhere, and emphasize the inter-related temporal and spatial variations in habitats and fluxes especially in aquatic systems with large seasonal variations in extent.
|
|
| 8. |
- Bose, Sourav, et al.
(författare)
-
Optical Lithography Patterning of SiO2 Layers for Interface Passivation of Thin Film Solar Cells
- 2018
-
Ingår i: Solar RRL. - : Wiley. - 2367-198X. ; 2:12
-
Tidskriftsartikel (refereegranskat)abstract
- Ultrathin Cu(In,Ga)Se-2 solar cells are a promising way to reduce costs and to increase the electrical performance of thin film solar cells. An optical lithography process that can produce sub-micrometer contacts in a SiO2 passivation layer at the CIGS rear contact is developed in this work. Furthermore, an optimization of the patterning dimensions reveals constrains over the features sizes. High passivation areas of the rear contact are needed to passivate the CIGS interface so that high performing solar cells can be obtained. However, these dimensions should not be achieved by using long distances between the contacts as they lead to poor electrical performance due to poor carrier extraction. This study expands the choice of passivation materials already known for ultrathin solar cells and its fabrication techniques.
|
|
| 9. |
- Cunha, Jose M. V., et al.
(författare)
-
High-Performance and Industrially Viable Nanostructured SiOx Layers for Interface Passivation in Thin Film Solar Cells
- 2021
-
Ingår i: Solar RRL. - : John Wiley & Sons. - 2367-198X. ; 5:3
-
Tidskriftsartikel (refereegranskat)abstract
- Herein, it is demonstrated, by using industrial techniques, that a passivation layer with nanocontacts based on silicon oxide (SiOx) leads to significant improvements in the optoelectronical performance of ultrathin Cu(In,Ga)Se-2 (CIGS) solar cells. Two approaches are applied for contact patterning of the passivation layer: point contacts and line contacts. For two CIGS growth conditions, 550 and 500 degrees C, the SiOx passivation layer demonstrates positive passivation properties, which are supported by electrical simulations. Such positive effects lead to an increase in the light to power conversion efficiency value of 2.6% (absolute value) for passivated devices compared with a nonpassivated reference device. Strikingly, both passivation architectures present similar efficiency values. However, there is a trade-off between passivation effect and charge extraction, as demonstrated by the trade-off between open-circuit voltage (V-oc) and short-circuit current density (J(sc)) compared with fill factor (FF). For the first time, a fully industrial upscalable process combining SiOx as rear passivation layer deposited by chemical vapor deposition, with photolithography for line contacts, yields promising results toward high-performance and low-cost ultrathin CIGS solar cells with champion devices reaching efficiency values of 12%, demonstrating the potential of SiOx as a passivation material for energy conversion devices.
|
|
| 10. |
- de Melo, Michaela L, et al.
(författare)
-
Flood pulse regulation of bacterioplankton community composition in an Amazonian floodplain lake
- 2019
-
Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 64:1, s. 108-120
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding spatial and temporal dynamics of microbial communities is a central challenge in microbial ecology since microorganisms play a key role in ecosystem functioning and biogeochemical cycles. Amazonian aquatic systems comprise a dynamic mosaic of heterogeneous habits but are understudied and there is limited information about the mechanisms that shape bacterial community composition (BCC). There is a consensus that environmental selection (species sorting) and dispersal processes (source?sink dynamics) act in concert to shape the composition of these communities, but the relative importance of each mechanism may vary dramatically through time and between systems. Applying 16S rRNA gene amplicon high-throughput sequencing, we studied factors and processes that modulate BCC in an Amazonian floodplain lake and used source-tracking models to trace the main dispersal sources of microorganisms in the whole floodplain system during a full hydrological cycle. Our source-tracking models indicated that dispersal processes were predominant, explaining most of the BCC variability throughout the study period. We observed more sources contributing to the sink community during the falling water than rising water period, when contributions from the Solim?es River dominated. There was a clear seasonal pattern in BCC, closely related to environmental variables, suggesting that the successful establishment of dispersing bacteria also depends on environmental filtering that is linked to water flow. In summary, source?sink dynamics and species sorting were strongly affected by water exchange and connectivity with the main river that varied throughout the flood pulse cycle. Our results demonstrated the influence of lateral transport and temporal dynamics on BCC in Amazonian floodplain lakes that could ultimately impact regional carbon budgets and biogeochemical cycles.
|
|
