Neonatal and infant immune responses are characterized by a limited capability to generate protective Ab titers and memory B cells as seen in adults. Multiple studies support an immature or even ...impaired character of umbilical cord blood (UCB) B cells themselves. In this study, we provide a comprehensive molecular and functional comparison of B cell subsets from UCB and adult peripheral blood. Most UCB B cells have a mature, naive B cell phenotype as seen in adults. The UCB Ig repertoire is highly variable but interindividually conserved, as BCR clonotypes are frequently shared between neonates. Furthermore, UCB B cells show a distinct transcriptional program that confers accelerated responsiveness to stimulation and facilitated IgA class switching. Stimulation drives extensive differentiation into Ab-secreting cells, presumably limiting memory B cell formation. Humanized mice suggest that the distinctness of UCB versus adult B cells is already reflected by the developmental program of hematopoietic precursors, arguing for a layered B-1/B-2 lineage system as in mice, albeit our findings suggest only partial comparability to murine B-1 cells. Our study shows that UCB B cells are not immature or impaired but differ from their adult mature counterpart in a conserved BCR repertoire, efficient IgA class switching, and accelerated, likely transient response dynamics.
Genetic and epigenetic aberrations contribute to the initiation and progression of acute myeloid leukemia (AML). GFI1, a zinc-finger transcriptional repressor, exerts its function by recruiting ...histone deacetylases to target genes. We present data that low expression of GFI1 is associated with an inferior prognosis of AML patients. To elucidate the mechanism behind this, we generated a humanized mouse strain with reduced GFI1 expression (GFI1-KD). Here we show that AML development induced by onco-fusion proteins such as MLL-AF9 or NUP98-HOXD13 is accelerated in mice with low human GFI1 expression. Leukemic cells from animals that express low levels of GFI1 show increased H3K9 acetylation compared to leukemic cells from mice with normal human GFI1 expression, resulting in the upregulation of genes involved in leukemogenesis. We investigated a new epigenetic therapy approach for this subgroup of AML patients. We could show that AML blasts from GFI1-KD mice and from AML patients with low GFI1 levels were more sensitive to treatment with histone acetyltransferase inhibitors than cells with normal GFI1 expression levels. We suggest therefore that GFI1 has a dose-dependent role in AML progression and development. GFI1 levels are involved in epigenetic regulation, which could open new therapeutic approaches for AML patients.
Heteropolyacids (HPA) with Keggin structures, such as H
3
PMo
12
O
40
(H
3
PMo), have been described as efficient catalysts in trans/esterification reactions due to their tolerance to water and free ...fatty acids contents, with particularly well-suited characteristics of high proton mobility and stability. The versatile array of HPA is considerably increased when such catalysts are supported onto solid matrices. In this sense, Al
2
O
3
was assessed as support for H
3
PMo to be used in trans/esterification reactions to produce biodiesel from high-acid feedstocks. The catalyst structure was characterized and applied on trans/esterification reaction of acid oils using ethanol as acyl acceptor. A face centered composite design was employed to conduct the experimental design and results analysis, taking macaw palm oil as study model. The process achieved an optimum level of 99.8% ester content and 4.1 mm
2
s
−1
viscosity under the following reaction conditions: 190 °C reaction temperature, 50 : 1 ethanol-to-oil molar ratio and 13.0% catalyst concentration. Other tested feedstocks (fungal single cell oil and residual frying oil) were also tested promoting satisfactory results, though the parameters were found to be slightly outside the limits set by the USA (ASTM D6715) standard. The H
3
PMo/Al
2
O
3
catalyst presented good regeneration and can be reused for up to four reaction cycles and requires lower ethanol-to-oil ratio, temperature, and catalyst concentration in comparison with other data from the literature.
Heteropolyacids (HPA) with Keggin structures, such as H
3
PMo
12
O
40
(H
3
PMo), have been described as efficient catalysts in trans/esterifications of high-acid feedstocks due to their tolerance to water and free fatty acids contents.
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•Sulfated niobium oxide shows efficient conversion of macaw palm oil into biodiesel.•Process conditions were established by response surface methodology.•Results are in close ...agreement with the model predictions.•The catalyst could be reused for five recycles with no major loss of activity.
Heterogeneous catalysis applied to esterification and transesterification of non-edible oil offers a strategy to the clean synthesis of the biodiesel and is driving research interested into the development of acid catalysts for efficient conversion of low quality vegetable oils into fuels to meet future societal demands. Thus, sulfated niobium oxide catalyst was synthesized by the impregnation method and used as a heterogeneous catalyst aimed at biodiesel production via macaw palm oil through high free fatty acid content transesterification with ethanol. The effect of two reaction parameters, molar ratio of ethanol to macaw palm oil and reaction temperature, on ester content and viscosity was studied by the response surface methodology (RSM). The ester content was determined by GC. The catalyst shows excellent activity (99.2% ester content and 4.5mm2/s viscosity) towards biodiesel production. Its optimum reaction conditions were: 120:1 molar ratio of ethanol to macaw palm oil at 250°C reaction temperature. The catalysts characterization was carried out by using the X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), and N2 Adsorption-desorption and Surface Acidity Analyses.
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•Two approaches for transesterification reaction of filamentous fungus were compared.•Ethanol was used for lipid extraction and acyl acceptor.•Reactions were catalyzed by ...heteropolyacid impregnated on alumina (H3PMo/Al2O3).•High levels of FAEE (>97%) were attained by both procedures.•Direct transesterification of biomass is simpler and renewable process.
Biodiesel production from Mucor circinelloides biomass was investigated by conventional method involving the lipid extraction using ethanol followed by transesterification (two-step process) in comparison with directly producing from the whole biomass without extraction (one-step process). Both processes used solid heteropolyacid catalyst (12-molybdophosphoric acid (H3PMo12O40) support on alumina (Al2O3) under conditions previously set up (200°C for 4h). Either one or two-step process was able to convert the microbial lipids into ethyl esters (FAEE) with high yields (97%), though the former simplifies the production process due to the elimination of an oil extraction step that incurs oil loss. Moreover, to minimize the energy used for dewatering, this method can be also used for transesterification of wet M. circinelloides biomass. Direct transesterification of wet biomass greatly simplifies the process of FAEE production by eliminating the drying and oil extraction steps, making this a renewable and environmental friendly process.
A combined effect of reaction temperature, ethanol-to-oil molar ratio and catalyst concentration on biodiesel production by H3PMo12O40 (HPMo) supported on niobia from macaw palm oil (Acrocomia ...aculeata) with high free fatty acid content has been studied herein through the response surface methodology. A 23 face centered central composite design was employed in order to conduct the experimental design and results analysis. Optimum conditions were found to be at 210 °C reaction temperature, 90:1 ethanol-to-oil molar ratio and 20.0% catalyst concentration, rendering high-quality biodiesel (99.65% ester content, 4.90 mm2/s viscosity and low monoacylglycerol and diacylglycerol levels). Such high performance can be associated with the catalyst satisfactory features, as characterized by typical analyses such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), N2 Adsorption-desorption and Surface acidity. Furthermore, the catalyst can be reused with no notable loss of catalytic activity until the second reaction cycle, thus maintaining an ester content higher than 94%.
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•Mesoporous solid acid catalyst was prepared and characterized.•Biodiesel from macaw palm oil having high FFA level was produced by ethonolysis.•Process optimization was performed by Response Surface Methodology.•The optimum conditions led to a high-quality biodiesel (99.65% ester content).•Catalyst can be reused twice with no notable loss of activity.
Solid waste from the red ceramic industry (chamotte clay) was assessed as glycerol adsorbent for biodiesel purification by dry washing. Its structure and composition was analyzed by several ...techniques, such as X-ray diffraction, FT-IR, scanning electron microscopy and particle size. By using a simulated medium (5w/v% glycerol in an ethanol solution), a face centered composite design was used to analyze the combined effect of chamotte concentration and temperature on glycerol removal. Chamotte levels of 2.5w/v% at 45°C maximized glycerol removal (1282mgglycerolg−1) with minimum loss of adsorbate. Kinetic data on glycerol adsorption by chamotte clay could be adjusted using the pseudo-second order model, which indicates that the rate-limiting step may be chemisorption. Moreover, chamotte clay was used for purifying ethyl biodiesel samples from palm kernel oil by chemical and biochemical catalysis. In the presence of chamotte clay, low glycerol levels (<0.02wt%) were found in comparison with crude biodiesel (0.29±0.03wt%). Chamotte clay was also able to remove residual levels of monoacylglycerols and diacylglycerols and provided samples with properties that are similar to those attained by traditional wet washing.
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•Chamotte clay an alternative sorbent for biodiesel purification was examined•Addition of 2.5 wt% at 45 °C removed 98% of glycerol from crude biodiesel.•Maximum predicted glycerol adsorption is 1282 mg g−1.•The adsorption process is controlled by chemisorption.•Chamotte was efficient for glycerol removal under batch and continuous runs
Increased costs and limited availability of traditional lipid sources for biodiesel production encourage researchers to find more sustainable feedstock at low prices. Microbial lipid stands out as ...feedstock replacement for vegetable oil to convert fatty acid esters. In this study, the potential of three isolates of filamentous fungi (Mucor circinelloides URM 4140, M. hiemalis URM 4144, and Penicillium citrinum URM 4126) has been assessed as single-cell oil (SCO) producers. M. circinelloides 4140 had the highest biomass concentration with lipid accumulation of up to 28 wt% at 120 hr of cultivation. The profile of fatty acids revealed a high content of saturated (SFA) and monounsaturated fatty acids (MUFA), including palmitic (C16:0, 33.2-44.1 wt%) and oleic (C18:1, 20.7-31.2 wt%) acids, with the absence of polyunsaturated fatty acids (PUFA) having more than four double bonds. Furthermore, the predicted properties of biodiesel generated from synthesized SCOs have been estimated by using empirical models which were in accordance with the limits imposed by the USA (ASTM D6715), European Union (EN 14214), and Brazilian (ANP 45/2014) standards. These results suggest that the assessed filamentous fungus strains can be considered as alternative feedstock sources for high-quality biofuel production.
Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals ...were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data.
An approach to producing biodiesel is the esterification of free fatty acids with an acyl acceptor. Free fatty acids can be produced through the hydrolysis of acylglycerols and represent a somewhat ...challenging feedstock for the production of biodiesel due to slower kinetics and the production of water in the reaction. The purpose of this work was to demonstrate the feasibility of a Keggin-structured heteropolyacid, H
3
PW
12
O
40
(HPW) supported onto Nb
2
O
5
to be used as a catalyst for the reaction of free fatty acids with ethanol to produce ethyl esters that comply with biodiesel norm values. The use of heteropolyacids as heterogeneous catalysts may present advantageous operational benefits, including the tolerance to residual water present in the medium and the potential for reusability. The catalyst was prepared via impregnation of HPW onto Nb
2
O
5
and was characterized in terms of acidity and surface properties. The enzymatic hydrolysis of macaw palm oil yielded a feedstock containing a free fatty acid content greater than 93%. The hydrolysate was assessed as a reactant for the esterification reaction, evaluating temperature, molar ratio, and catalyst amount, leading to optimal conversions greater than 99% with viscosity and density within the regulatory limits for biodiesel. The use of heterogeneous acid catalysts, such as HPW/Nb
2
O
5
, represents a potentially feasible alternative to unlocking the potential of working with challenging feedstocks as oil hydrolysates.
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