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1.
J Environ Manage ; 358: 120909, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38642487

RESUMO

Achieving an equilibrium between exceptional oil absorption and remarkable elasticity has emerged as a formidable challenge for magnetic porous materials designed for oil absorption. Here, we propose an original, magnetic and superhydrophobic cellulose nanofibril (CNF) based aerogel system with a rope-ladder like skeleton by to greatly improve the issue. Within this system, CNF as the skeleton was combined with multiwalled carbon nanotubes (MWCNT)@Fe3O4 as the magnetic and enhanced component, both methyltrimethoxysilane (MTMS) and acetonitrile-extracted lignin (AEL) as the soft-hard associating constituents. The resultant CNF based aerogel shows a rope-ladder like pore structure to contribute to high elasticity and excellent oil absorption (28.34-61.09 g/g for various oils and organic solvents) under the synergistic effect of Fe3O4@MWCNT, AEL and MTMS, as well as good specific surface area (27.97 m2/g), low density (26.4 mg/cm3). Notably, despite the introduced considerable proportion (0.5 times of mass-CNF) of Fe3O4@MWCNT, the aerogel retained an impressive compression-decompression rate (88%) and the oil absorption efficiency of above 87% for various oils due to the soft-hard associating structure supported by both MTMS and AEL. This study provides a prospective strategy to balance between high elasticity and excellent oil absorption of CNF based aerogel doping inorganic particles.


Assuntos
Celulose , Interações Hidrofóbicas e Hidrofílicas , Nanofibras , Celulose/química , Nanofibras/química , Óleos/química , Géis/química , Nanotubos de Carbono/química , Elasticidade , Porosidade
2.
iScience ; 27(4): 109315, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38487547

RESUMO

As the only cell type responsible for oxygen delivery, erythrocytes play a crucial role in supplying oxygen to hypoxic tissues, ensuring their normal functions. Hypoxia commonly occurs under physiological or pathological conditions, and understanding how erythrocytes adapt to hypoxia is fundamental for exploring the mechanisms of hypoxic diseases. Additionally, investigating acute and chronic mountain sickness caused by plateaus, which are naturally hypoxic environments, will aid in the study of hypoxic diseases. In recent years, increasingly developed proteomics and metabolomics technologies have become powerful tools for studying mature enucleated erythrocytes, which has significantly contributed to clarifying how hypoxia affects erythrocytes. The aim of this article is to summarize the composition of the cytoskeleton and cytoplasmic proteins of hypoxia-altered erythrocytes and explore the impact of hypoxia on their essential functions. Furthermore, we discuss the role of microRNAs in the adaptation of erythrocytes to hypoxia, providing new perspectives on hypoxia-related diseases.

3.
Int J Biol Macromol ; 265(Pt 1): 130807, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484808

RESUMO

Magnetic superhydrophobic materials have broad application prospect in oil-water separation. In this study, a magnetic and superhydrophobic aerogel with lamellar structure was successfully prepared using cellulose nanofibrils (CNF) as the skeleton, Fe3O4 as the magnetic ion, 1H, 1H, 2H, 2H trialkylfluorooctane triethoxysilane (FS) and 3-(2-aminoethyl amino)-propyl trimethoxysilane (AS) as the combined modifier. The prepared aerogel shows lower density (38.63 mg/cm3), excellent magnetic (15.13 emu/g), high elasticity and good oil sorption properties (21 g/g). In addition, FS/AS also exhibits excellent mechanical properties and superhydrophobic ability (water contact angle (WCA) of 151.9 ± 1.4°), as it provides sufficient toughness and low surface energy for the layer-branch structure. It should be noted that the entire preparation process is carried out in the aqueous phase, without the use of any organic solvents, providing a green oil-water separation strategy.


Assuntos
Celulose , Água , Elasticidade , Compostos Radiofarmacêuticos , Interações Hidrofóbicas e Hidrofílicas
4.
Int J Biol Macromol ; 258(Pt 2): 128918, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134986

RESUMO

Applications for polylactic acid (PLA) are significantly impacted by its poor mechanical properties and lack of thermal stability. The goal of this work is to bridge the gap of poor compatibility among the components and enhance their interface interlocking capability to improve the toughness and thermal stability. Ultrafine bamboo charcoal (UFBC) was treated through deep eutectic solvent (DES) method to deposit sodium lignosulfonate (LS) on its surface. LS was used with PLA as a bio-coupling agent to create an eco-friendly PLA composite film with a wide range of characteristics. Benefiting from the penetration of PLA to the internal pores in UFBC, the resultant L-UFBC/PLA film has a good mechanical interlocking structure. Ls can increase the compatibility and strengthen the interface interlocking capability through DES method, which greatly improves the mechanical properties of the system. In comparison to pure PLA one, the elongation at break was 136.24 % greater, and the crystallinity (Xc) increased from 1.09 % to 3.33 %. Furthermore, the thermal stability of the system was also improved, and the residual at 600 °C rose by 4.83 %. These characteristics offer the prepared L-UFBC/PLA film a wide range of potential applications in the packaging, medical, agricultural, and other sectors.


Assuntos
Agricultura , Carvão Vegetal , Análise por Conglomerados , Poliésteres
5.
Front Genet ; 13: 927018, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36061178

RESUMO

Objective: This study aimed to identify specific dysregulated genes with potential diagnostic and predictive values for JAK2V617F + myelofibrosis. Methods: Two gene expression datasets of CD34+ hematopoietic stem and progenitor cells (HSPCs) from patients with JAK2V617F + myeloproliferative neoplasm (MPN) [n = 66, including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF)] and healthy controls (HC) (n = 30) were acquired from the GEO (Gene Expression Omnibus) database. The differentially expressed genes (DEGs) were screened between each JAK2V617F + MPN entity and HC. Subsequently, functional enrichment analyses, including Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome, and Gene Set Enrichment Analysis (GSEA), were conducted to decipher the important biological effects of DEGs. Protein-protein interaction (PPI) networks of the DEGs were constructed to identify hub genes and significant modules. Another two gene expression profiles of patients with JAK2V617F + MPN [n = 23, including PV, ET, secondary myelofibrosis (SMF), and PMF] and HC (n = 6) from GEO were used as external validation datasets to prove the reliability of the identified signatures. Results: KEGG analysis revealed the upregulated genes in three JAK2V617F + MPN entities compared with HC were essentially enriched in inflammatory pathways and immune response signaling pathways, and the number of these pathways enriched in PMF was obviously more than that in PV and ET. Following the PPI analysis, 10 genes primarily related to inflammation and immune response were found upregulated in different JAK2V617F + MPN entities. In addition, Reactome enrichment analysis indicated that interferon signaling pathways were enriched specifically in PMF but not in PV or ET. Furthermore, several interferon (IFN)-stimulated genes were identified to be uniquely upregulated in JAK2V617F + PMF. The external datasets validated the upregulation of four interferon-related genes (OAS1, IFITM3, GBP1, and GBP2) in JAK2V617F + myelofibrosis. The receiver operating characteristic (ROC) curves indicate that the four genes have high area under the ROC curve (AUC) values when distinguishing JAK2V617F + myelofibrosis from PV or ET. Conclusion: Four interferon-stimulated genes (OAS1, IFITM3, GBP1, and GBP2) exclusively upregulated in JAK2V617F + myelofibrosis might have the potential to be the auxiliary molecular diagnostic and predictive indicators of myelofibrosis.

6.
Evol Dev ; 24(5): 158-170, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35971657

RESUMO

Stripe patterns are a striking example for a repeatedly evolved color pattern. In the African adaptive radiations of cichlid fishes, stripes evolved several times independently. Previously, it has been suggested that regulatory evolution of a single gene, agouti-related-peptide 2 (agrp2), explains the evolutionary lability of this trait. Here, using a comparative transcriptomic approach, we performed comparisons between (adult) striped and nonstriped cichlid fishes of representatives of Lake Victoria and the two major clades of Lake Malawi (mbuna and non-mbuna lineage). We identify agrp2 to be differentially expressed across all pairwise comparisons, reaffirming its association with stripe pattern divergence. We therefore also provide evidence that agrp2 is associated with the loss of the nonstereotypic oblique stripe of Mylochromis mola. Complementary ontogenetic data give insights into the development of stripe patterns as well as vertical bar patterns that both develop postembryonically. Lastly, using the Lake Victoria species pair Haplochromis sauvagei and Pundamilia nyererei, we investigated the differences between melanic and non-melanic regions to identify additional genes that contribute to the formation of stripes. Expression differences-that most importantly also do not include agrp2-are surprisingly small. This suggests, at least in this species pair, that the stripe phenotype might be caused by a combination of more subtle transcriptomic differences or cellular changes without transcriptional correlates. In summary, our comprehensive analysis highlights the ontogenetic and adult transcriptomic differences between cichlids with different color patterns and serves as a basis for further investigation of the mechanistic underpinnings of their diversification.


Assuntos
Ciclídeos , Animais , Ciclídeos/genética , Perfilação da Expressão Gênica , Lagos , Fenótipo , Transcriptoma
7.
Nat Commun ; 13(1): 296, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027541

RESUMO

Polymorphisms have fascinated biologists for a long time, but their genetic underpinnings often remain elusive. Here, we aim to uncover the genetic basis of the gold/dark polymorphism that is eponymous of Midas cichlid fish (Amphilophus spp.) adaptive radiations in Nicaraguan crater lakes. While most Midas cichlids are of the melanic "dark morph", about 10% of individuals lose their melanic pigmentation during their ontogeny and transition into a conspicuous "gold morph". Using a new haplotype-resolved long-read assembly we discover an 8.2 kb, transposon-derived inverted repeat in an intron of an undescribed gene, which we term goldentouch in reference to the Greek myth of King Midas. The gene goldentouch is differentially expressed between morphs, presumably due to structural implications of inverted repeats in both DNA and/or RNA (cruciform and hairpin formation). The near-perfect association of the insertion with the phenotype across independent populations suggests that it likely underlies this trans-specific, stable polymorphism.


Assuntos
Ciclídeos/genética , Íntrons , Polimorfismo Genético , Animais , Evolução Molecular , Estudo de Associação Genômica Ampla , Genótipo , Lagos , Fenótipo , Pigmentação
8.
Biol Open ; 10(9)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34463758

RESUMO

Molecular and cellular mechanisms underlying variation in adult form remain largely unknown. Adult pigment patterns of fishes in the genus Danio, which includes zebrafish, Danio rerio, consist of horizontal stripes, vertical bars, spots and uniform patterns, and provide an outstanding opportunity to identify causes of species level variation in a neural crest derived trait. Understanding pigment pattern variation requires quantitative approaches to assess phenotypes, yet such methods have been mostly lacking for pigment patterns. We introduce metrics derived from information theory that describe patterns and pattern variation in Danio fishes. We find that these metrics used singly and in multivariate combinations are suitable for distinguishing general pattern types, and can reveal even subtle phenotypic differences attributable to mutations. Our study provides new tools for analyzing pigment pattern in Danio and potentially other groups, and sets the stage for future analyses of pattern morphospace and its mechanistic underpinnings.


Assuntos
Desenvolvimento Embrionário/genética , Metamorfose Biológica/genética , Crista Neural/embriologia , Pigmentação/genética , Peixe-Zebra/embriologia , Animais , Evolução Biológica , Embrião não Mamífero , Mutação , Fenótipo
9.
J Exp Zool B Mol Dev Evol ; 336(5): 443-450, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33755299

RESUMO

While color patterns are highly diverse across the animal kingdom, certain patterns such as countershading and stripe patterns have evolved repeatedly. Across vertebrates, agouti-signaling genes have been associated with the evolution of both patterns. Here we study the functional conservation and divergence by investigating the expression patterns of the two color-pattern-related agouti-signaling genes, agouti-signaling protein 1 (asip1) and agouti-signaling protein 2b (asip2b, also known as agrp2) in Teleostei. We show that the dorsoventral expression profile of asip1 and the role of the "stripe repressor" asip2b are shared across multiple teleost lineages and uncover a previously unknown association between stripe-interstripe patterning and both asip1 and asip2b expression. In some species, including the zebrafish (Danio rerio), these two genes show complementary and overlapping expression patterns in line with functional redundancy. Our results thus suggest how conserved and novel functions of agouti-signaling genes might have shaped the evolution of color patterns across teleost fishes.


Assuntos
Proteína Agouti Sinalizadora/metabolismo , Peixes/fisiologia , Regulação da Expressão Gênica/fisiologia , Pigmentação/fisiologia , Proteína Agouti Sinalizadora/classificação , Proteína Agouti Sinalizadora/genética , Animais , Peixes/anatomia & histologia , Peixes/classificação , Peixes/genética , Filogenia , Pigmentação/genética , Pigmentos Biológicos
10.
Sci Rep ; 10(1): 12329, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32704058

RESUMO

Many species change their coloration during ontogeny or even as adults. Color change hereby often serves as sexual or status signal. The cellular and subcellular changes that drive color change and how they are orchestrated have been barely understood, but a deeper knowledge of the underlying processes is important to our understanding of how such plastic changes develop and evolve. Here we studied the color change of the Malawi golden cichlid (Melanchromis auratus). Females and subordinate males of this species are yellow and white with two prominent black stripes (yellow morph; female and non-breeding male coloration), while dominant males change their color and completely invert this pattern with the yellow and white regions becoming black, and the black stripes becoming white to iridescent blue (dark morph; male breeding coloration). A comparison of the two morphs reveals that substantial changes across multiple levels of biological organization underlie this polyphenism. These include changes in pigment cell (chromatophore) number, intracellular dispersal of pigments, and tilting of reflective platelets (iridosomes) within iridophores. At the transcriptional level, we find differences in pigmentation gene expression between these two color morphs but, surprisingly, 80% of the genes overexpressed in the dark morph relate to neuronal processes including synapse formation. Nerve fiber staining confirms that scales of the dark morph are indeed innervated by 1.3 to 2 times more axonal fibers. Our results might suggest an instructive role of nervous innervation orchestrating the complex cellular and ultrastructural changes that drive the morphological color change of this cichlid species.


Assuntos
Axônios/metabolismo , Ciclídeos/anatomia & histologia , Ciclídeos/fisiologia , Pigmentação , Caracteres Sexuais , Animais , Axônios/ultraestrutura , Cromatóforos/metabolismo , Cromatóforos/ultraestrutura , Ciclídeos/genética , Epitélio/metabolismo , Feminino , Masculino , Fenótipo , Pele/anatomia & histologia , Transcriptoma/genética , Regulação para Cima/genética
11.
Front Cell Dev Biol ; 8: 62, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117987

RESUMO

The East African adaptive radiations of cichlid fishes are renowned for their diversity in coloration. Yet, the developmental basis of pigment pattern formation remains largely unknown. One of the most common melanic patterns in cichlid fishes are vertical bar patterns. Here we describe the ontogeny of this conspicuous pattern in the Lake Kyoga species Haplochromis latifasciatus. Beginning with the larval stages we tracked the formation of this stereotypic color pattern and discovered that its macroscopic appearance is largely explained by an increase in melanophore density and accumulation of melanin during the first 3 weeks post-fertilization. The embryonal analysis is complemented with cytological quantifications of pigment cells in adult scales and the dermis beneath the scales. In adults, melanic bars are characterized by a two to threefold higher density of melanophores than in the intervening yellow interbars. We found no strong support for differences in other pigment cell types such as xanthophores. Quantitative PCRs for twelve known pigmentation genes showed that expression of melanin synthesis genes tyr and tyrp1a is increased five to sixfold in melanic bars, while xanthophore and iridophore marker genes are not differentially expressed. In summary, we provide novel insights on how vertical bars, one of the most widespread vertebrate color patterns, are formed through dynamic control of melanophore density, melanin synthesis and melanosome dispersal.

12.
Genome Biol Evol ; 11(12): 3452-3465, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31821504

RESUMO

Color patterns in African cichlid fishes vary spectacularly. Although phylogenetic analysis showed already 30 years ago that many color patterns evolved repeatedly in these adaptive radiations, only recently have we begun to understand the genomic basis of color variation. Horizontal stripe patterns evolved and were lost several times independently across the adaptive radiations of Lake Victoria, Malawi, and Tanganyika and regulatory evolution of agouti-related peptide 2 (agrp2/asip2b) has been linked to this phenotypically labile trait. Here, we asked whether the agrp2 locus exhibits particular characteristics that facilitate divergence in color patterns. Based on comparative genomic analyses, we discovered several recent duplications, insertions, and deletions. Interestingly, one of these events resulted in a tandem duplication of the last exon of agrp2. The duplication likely precedes the East African radiations that started 8-12 Ma, is not fixed within any of the radiations, and is found to vary even within some species. Moreover, we also observed variation in copy number (two to five copies) and secondary loss of the duplication, illustrating a surprising dynamic at this locus that possibly promoted functional divergence of agrp2. Our work suggests that such instances of exon duplications are a neglected mechanism potentially involved in the repeated evolution and diversification that deserves more attention.


Assuntos
Proteína Relacionada com Agouti/genética , Ciclídeos/genética , Evolução Molecular , Pigmentação da Pele , Animais , Ciclídeos/classificação , Éxons , Duplicação Gênica , Genômica , Mutação INDEL , Filogenia , Seleção Genética , Pigmentação da Pele/genética , Transcrição Gênica
13.
Science ; 362(6413): 457-460, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30361373

RESUMO

The color patterns of African cichlid fishes provide notable examples of phenotypic convergence. Across the more than 1200 East African rift lake species, melanic horizontal stripes have evolved numerous times. We discovered that regulatory changes of the gene agouti-related peptide 2 (agrp2) act as molecular switches controlling this evolutionarily labile phenotype. Reduced agrp2 expression is convergently associated with the presence of stripe patterns across species flocks. However, cis-regulatory mutations are not predictive of stripes across radiations, suggesting independent regulatory mechanisms. Genetic mapping confirms the link between the agrp2 locus and stripe patterns. The crucial role of agrp2 is further supported by a CRISPR-Cas9 knockout that reconstitutes stripes in a nonstriped cichlid. Thus, we unveil how a single gene affects the convergent evolution of a complex color pattern.


Assuntos
Proteína Relacionada com Agouti/fisiologia , Evolução Biológica , Ciclídeos/anatomia & histologia , Ciclídeos/fisiologia , Pigmentação da Pele , Proteína Relacionada com Agouti/genética , Animais , Sistemas CRISPR-Cas , Mapeamento Cromossômico , Ciclídeos/genética , Técnicas de Inativação de Genes , Loci Gênicos , Mutação , Pigmentação da Pele/genética
14.
BMC Dev Biol ; 17(1): 15, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29169323

RESUMO

BACKGROUND: The Midas cichlid species complex (Amphilophus spp.) is widely known among evolutionary biologists as a model system for sympatric speciation and adaptive phenotypic divergence within extremely short periods of time (a few hundred generations). The repeated parallel evolution of adaptive phenotypes in this radiation, combined with their near genetic identity, makes them an excellent model for studying phenotypic diversification. While many ecological and evolutionary studies have been performed on Midas cichlids, the molecular basis of specific phenotypes, particularly adaptations, and their underlying coding and cis-regulatory changes have not yet been studied thoroughly. RESULTS: For the first time in any New World cichlid, we use Tol2 transposon-mediated transgenesis in the Midas cichlid (Amphilophus citrinellus). By adapting existing microinjection protocols, we established an effective protocol for transgenesis in Midas cichlids. Embryos were injected with a Tol2 plasmid construct that drives enhanced green fluorescent protein (eGFP) expression under the control of the ubiquitin promoter. The transgene was successfully integrated into the germline, driving strong ubiquitous expression of eGFP in the first transgenic Midas cichlid line. Additionally, we show transient expression of two further transgenic constructs, ubiquitin::tdTomato and mitfa::eGFP. Transgenesis in Midas cichlids will facilitate further investigation of the genetic basis of species-specific traits, many of which are adaptations. CONCLUSION: Transgenesis is a versatile tool not only for studying regulatory elements such as promoters and enhancers, but also for testing gene function through overexpression of allelic gene variants. As such, it is an important first step in establishing the Midas cichlid as a powerful model for studying adaptive coding and non-coding changes in an ecological and evolutionary context.


Assuntos
Ciclídeos/genética , Elementos de DNA Transponíveis/genética , Animais , Ecologia , Evolução Molecular , Técnicas de Transferência de Genes , Especiação Genética , Especificidade da Espécie
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