Embryonic stem cells (ESCs) can instruct the conversion of differentiated cells toward pluripotency following cell-to-cell fusion by a mechanism that is rapid but poorly understood. Here, we used ...centrifugal elutriation to enrich for mouse ESCs at sequential stages of the cell cycle and showed that ESCs in S/G2 phases have an enhanced capacity to dominantly reprogram lymphocytes and fibroblasts in heterokaryon and hybrid assays. Reprogramming success was associated with an ability to induce precocious nucleotide incorporation within the somatic partner nuclei in heterokaryons. BrdU pulse-labeling experiments revealed that virtually all successfully reprogrammed somatic nuclei, identified on the basis of Oct4 re-expression, had undergone DNA synthesis within 24 hr of fusion with ESCs. This was essential for successful reprogramming because drugs that inhibited DNA polymerase activity effectively blocked pluripotent conversion. These data indicate that nucleotide incorporation is an early and critical event in the epigenetic reprogramming of somatic cells in experimental ESC-heterokaryons.
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► Counterflow centrifugal elutriation enriches for specific cell-cycle stages in ESCs ► S/G2-enriched ESCs have an enhanced capacity to reprogram somatic cells ► DNA synthesis is critical in fusion-mediated reprogramming of somatic cells by ESCs
The capacity of mouse embryonic stem cells (ESCs) to reprogram somatic cells within heterokaryons requires induction of DNA synthesis in the somatic nucleus, suggesting that DNA replication is essential for the successful conversion of somatic cells toward pluripotency.
In burn trauma, hands are often injured due to defensive action or proximity to the causative agent, leading to significant morbidity during a patients work and social rehabilitation process. In this ...context, the use of patient-reported outcome measures is a first step in measuring and improving these outcomes. The Burned Hand Outcome Tool (BHOT) is a specific questionnaire for adults with burned hands aimed at quantifying outcomes related to this trauma.
To translate, culturally adapt, and validate the BHOT into Brazilian Portuguese.
Following established standards in the literature, the original English questionnaire was translated, back translated, and analyzed by a panel of experts in the field. Cultural adaptation of the translation was carried out with a sample of target patients. The questionnaire was validated concurrently with the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire translated into Portuguese, at three time points (0 h, 2 h, 48 h), with two different evaluators.
The cultural adaptation was conducted on a sample of 30 adult patients with hand burns without the need for reassessment of the translated items. The questionnaire validation was carried out on a sample of 100 adult patients with hand burns. The Cronbach's Alpha found at the first time point was 0.936. The correlations between the questionnaires varied from 0.656 to 0.915.
The Burned Hand Outcome Tool has been translated, culturally adapted, and validated for a target population in Brazilian Portuguese.
•Patient-reported outcomes measures (PROMs) are important in the quest for patient centered holistic care in burns.•The translation process of the Burnt hand outcomes tool (BHOT) into Brazilian Portuguese followed a standardized approach.•The translation of questionnaires guide treatments, track progress, and foster a collaborative, patient-centered care.
Mixed-species plantations of Eucalyptus and legume trees can symbiotically fix nitrogen and potentially improve the soil quality and biomass productivity compared with a conventional Eucalyptus ...monoculture. In this study, we evaluated changes in the structure and abundance of different microbial groups and nitrogen cycle genes in mixed and pure plantations of Acacia mangium and Eucalyptus urograndis in an experimental area in southeastern Brazil. Soil samples (0–10 cm) collected in two- and three-year-old stands were submitted to chemical characterization and molecular analyses using DGGE and real time-PCR for bacteria (16S rRNA), fungi (ITS), and genes involved in nitrogen cycling (nirK, amoA, nifH). The mixed plantation did not significantly change general soil fertility or total soil C and N content compared with the Eucalyptus monoculture. However, there was a significant increase in available phosphorus and soil nitrate content in both the A. mangium and mixed-species treatments. The multivariate ordination of the DGGE profiles of bacteria, fungi and archaea groups showed distinct community structures in each treatment. Significant differences in the abundance of copies of the target genes were found for fungi, with higher values in the Eucalyptus followed by the mixed and A. mangium plantations. The analysis of nitrogen cycle genes showed no clear difference in the communities of nitrogen fixing bacteria or nitrifying archaea among treatments. The nitrification activity was dominated by archaea because it was not possible to detect the presence of bacterial nitrifiers; the denitrifier community had a distinct profile in the Eucalyptus monoculture. The abundance of archaeal amoA and nirK genes suggests that the A. mangium treatment had higher nitrification and lower denitrification than the other treatments, which would explain the higher soil nitrate levels found in pure A. mangium treatments. Our data suggest that mixed plantations of E. urograndis and A. mangium result in a distinct microbial community relative to the respective monocultures with positive effects on soil phosphorus and nitrate content, which potentially reduces the need for anthropogenic fertilization.
•We studied soil fertility and microbiology in an Acacia–Eucalyptus mixed plantation.•The monocultures and the mixed plantation increased soil C and N over time.•Acacia and mixed plantation showed higher soil nitrate and phosphorus than Eucalyptus.•Bacteria, fungi and Archaea community had structure altered by management practices.•Nitrate accumulation may resulted from nitrifiers increase and denitrifiers decrease.
Genomic imprinting directs the allele-specific marking and expression of loci according to their parental origin. Differential DNA methylation at imprinted control regions (ICRs) is established in ...gametes and, although largely preserved through development, can be experimentally reset by fusing somatic cells with embryonic germ cell (EGC) lines. Here, we show that the Ten-Eleven Translocation proteins Tet1 and Tet2 participate in the efficient erasure of imprints in this model system. The fusion of B cells with EGCs initiates pluripotent reprogramming, in which rapid re-expression of Oct4 is accompanied by an accumulation of 5-hydroxymethylcytosine (5hmC) at several ICRs. Tet2 was required for the efficient reprogramming capacity of EGCs, whereas Tet1 was necessary to induce 5-methylcytosine oxidation specifically at ICRs. These data show that the Tet1 and Tet2 proteins have discrete roles in cell-fusion-mediated pluripotent reprogramming and imprint erasure in somatic cells.
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► EGCs can erase DNA methylation at ICRs in somatic cells after fusion ► EGCs selectively induce 5hmC accumulation at ICRs in the somatic genome ► Conversion of 5mC to 5hmC at these imprinted domains requires Tet1 ► Tet2 depletion results in delayed reprogramming by EGCs
Flooding, economic losses in agricultural activity and climatological variability are very natural phenomena on plains. In particular, the central plains in Argentina, that are the most productive ...agrarian areas in the country, are characterized by significant alternate inter-annual droughts and floods. Moreover, the topographic features of the study area contribute to high exposure to flooding. In this study, a method for estimating the Hydrological Vulnerability (HV), related to the hydrological surplus, is developed for three river basins in the Pampas plains in Argentina, which includes a comprehensive analysis and scoring of various physical, climatological and hydrological variables. All the data were processed in a raster format, in a GIS environment. Finally, the method was validated, in a qualitative and a quantitative form, with a world and national disasters database, government national and satellite data and previous studies. It provides a structured approach for carrying out an assessment of hydrological vulnerability, which is applicable at different spatial scales.
Simple hydrological models, such as the Seasonal Water Yield Model developed by the Natural Capital Project (InVEST SWYM), are attractive as data requirements are relatively easy to satisfy. However, ...simple models may produce unrealistic results when the underlying hydrological processes are inadequately described. We used the variation in performance of the InVEST SWYM across watersheds to identify correlates of poorly modeled outcomes of InVEST SWYM. We grouped 749 watersheds from across North America into five bioclimatic regions using nine environmental variables. For each region, we compared the predicted flow patterns to actual flow conditions over a 15-year period. The correlation between the modeled and actual flows was highly dispersed and relatively poor, with 92% of r2 values less than 0.5 and 42% less than 0.1. We linked cryospheric variables to model performance in the bioclimatic region with the poorest model performance (the Low elevation Boreal Sub-humid region—LeBSh). After incorporating cryospheric conditions into the InVEST SWYM, predictions improved significantly in 30% of the LeBSh watersheds. We provide a relatively straightforward approach for identifying processes that simple hydrological models may not consider or which need further attention or refinement.
Temporal dynamics of a zooplankton community were examined in the surf zone of Pehuen Co beach (PC), Argentina. The effect of environmental variables on the zooplankton composition and abundance was ...also investigated. Samples were obtained monthly between December 2016 and November 2017 from a fixed site during low tide. In all, 37 taxa were representative of the community. Meroplankton represented 59.45% of the total taxa, whereas holoplankton reached 40.54%. Five species were dominant: Acartia tonsa in summer months (2032 ind. m−3 in March), Paracalanus parvus and Ctenocalanus vanus in winter (4055 ind. m−3 and 264 ind. m−3, respectively, in July), and the sergestid Peisos petrunkevitchi (838.7 ind. m−3 in September) and the mysids Arthromysis magellanica (284 ind. m−3 in October) in spring. The highest total zooplankton abundances were registered in summer and winter, and the lowest ones were registered in autumn. The zooplankton community showed a strong seasonality, which can be mainly attributed to temporal changes in water temperature and to variations in suspended particulate matter (SPM), particulate organic matter (POM), and chlorophyll-a (Chl-a). Our results show that the zooplankton community structure was also affected by local variations in the velocity of the littoral current (VLC) and the wave height (WH). The present study shows that, besides seasonality, which seemed to be strong in this temperate region, other events affect zooplankton dynamics at a short-term time scale. Both VLC and WH are key factors that affect the zooplankton community structure in PC.
•The zooplankton community showed a strong seasonality in surf zone waters.•Seasonality is mainly attributed to temporal changes in water temperature.•Abundance was affected by local variations of littoral current velocities and wave's height.•Surf-waters hydrodynamic can mask the effects of seasonality on zooplankton community.
This study explores the effect of different wind events (direction and duration) on the surf zone zooplankton community in a temperate sandy beach. Samplings were realized on the surf zone of Pehuen ...Co sandy beach during 17 wind events from May 17th, 2017, to July 19th, 2019. Biological samples were taken before and after the events. The identification of the events was realized using recorded high-frequency wind speed data. General Linear Model (LM) and Generalized linear models (GLM) were employed to compare physical and biological variables. We observed that the wind direction unequally altered the ecosystem along with its duration, modifying the composition and abundance of zooplankton communities. Short-duration wind events were associated with an increment in the zooplankton abundances, being Acartia tonsa and Paracalanus parvus dominant. Within the short-duration cases, winds from the W sector were identified with the inner continental shelf species' presence, such as Ctenocalanus vanus and Euterpina acutifrons, and to a lesser extent, Calanoides carinatus, and Labidocera fluviatilis, together with surf zone copepods. Long-duration cases were associated with a significant decrease in the zooplankton abundance. Within this group, SE-SW wind events were identified with adventitious fraction taxa. Considering that the occurrence of extreme events is growing because of climate change, affecting the frequency and intensity of storm surges, the knowledge of the responses of biological communities to these events is necessary. This work provides quantitative evidence on a short-time scale of the implications of the physical-biological interaction during different strong wind cases in surf zone waters of sandy beaches.
•Composition and abundance of surf zooplankton was highly affected by strong winds.•Wind direction and duration became a key factor establishing a different impact on the distribution of the zooplankton.•W winds events were identified with the inner continental shelf species' presence.•SE-SW wind events were identified with adventitious fraction taxa.•Short/long duration was associated to an increase/decrease of the abundances, respectively.
Areal variation in lakes is closely associated with other factors such as intensity of land use of the hydrological basins, climatology, geomorphology and depth. The main objective of this study is ...to assess the relationship between climatic variability events (El Niño Southern Oscillation, ENSO), land use and shallow lakes’ areal variations in the temperate plains of Argentina for the period 2002–2011. The standard precipitation evaporation index (SPEI) was employed in this study in conjunction with the oceanic Niño index (ONI) and in situ annual precipitation data to determine wet, dry and normal years. Shallow lakes’ areal variation was analyzed by satellite imagery (MODIS) processing and the variability of the land use intensity was determined based on agricultural estimations. Frequency in the maximum of shallow lake areas was relatively more dependent on any changes in the rainfall regime (ENSO events) than in the land use (decrease/increase of the cultivated area). The El Niño (2002/3) and La Niña (2007/8) events clearly affected the precipitations of the total studied lake regions, with maximum areas in 2002 and minimum in 2008. The results obtained may be an important contribution to mitigate flooding and droughts in the studied area.
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