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1.
Blood ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848513

RESUMEN

Comparison of the 2007 EORTC/ISCL and the 2022 EORTC/ISCL/USCLC blood staging guidelines for cutaneous T-cell lymphoma at a single institution reveals the newer guidelines fail to detect a subset of Sézary syndrome patients with low blood burden.

2.
Nucleic Acids Res ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869066

RESUMEN

Translational fidelity relies critically on correct aminoacyl-tRNA supply. The trans-editing factor AlaX predominantly hydrolyzes Ser-tRNAAla, functioning as a third sieve of alanyl-tRNA synthetase (AlaRS). Despite extensive studies in bacteria and archaea, the mechanism of trans-editing in mammals remains largely unknown. Here, we show that human AlaX (hAlaX), which is exclusively distributed in the cytoplasm, is an active trans-editing factor with strict Ser-specificity. In vitro, both hAlaX and yeast AlaX (ScAlaX) were capable of hydrolyzing nearly all Ser-mischarged cytoplasmic and mitochondrial tRNAs; and robustly edited cognate Ser-charged cytoplasmic and mitochondrial tRNASers. In vivo or cell-based studies revealed that loss of ScAlaX or hAlaX readily induced Ala- and Thr-to-Ser misincorporation. Overexpression of hAlaX impeded the decoding efficiency of consecutive Ser codons, implying its regulatory role in Ser codon decoding. Remarkably, yeast cells with ScAlaX deletion responded differently to translation inhibitor treatment, with a gain in geneticin resistance, but sensitivity to cycloheximide, both of which were rescued by editing-capable ScAlaX, alanyl- or threonyl-tRNA synthetase. Altogether, our results demonstrated the previously undescribed editing peculiarities of eukaryotic AlaXs, which provide multiple checkpoints to maintain the speed and fidelity of genetic decoding.

3.
Nucleic Acids Res ; 52(6): 3213-3233, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38227555

RESUMEN

N 6-Threonylcarbamoyladenosine at A37 (t6A37) of ANN-decoding transfer RNAs (tRNAs) is a universal modification whose functions have been well documented in bacteria and lower eukaryotes; however, its role in organellar translation is not completely understood. In this study, we deleted the mitochondrial t6A37-modifying enzyme OSGEPL1 in HEK293T cells. OSGEPL1 is dispensable for cell viability. t6A37 hypomodification selectively stimulated N1-methyladenosine at A9 (m1A9) and N2-methylguanosine at G10 (m2G10) modifications and caused a substantial reduction in the aminoacylation of mitochondrial tRNAThr and tRNALys, resulting in impaired translation efficiency. Multiple types of amino acid misincorporation due to the misreading of near-cognate codons by t6A37-unmodified tRNAs were detected, indicating a triggered translational infidelity. Accordingly, the alterations in mitochondrial structure, function, and the activated mitochondrial unfolded protein response were observed. Mitochondrial function was efficiently restored by wild-type, but not by tRNA-binding-defective OSGEPL1. Lastly, in Osgepl1 deletion mice, disruption to mitochondrial translation was evident but resulted in no observable deficiency under physiological conditions in heart, which displays the highest Osgepl1 expression. Taken together, our data delineate the multifaceted roles of mitochondrial t6A37 modification in translation efficiency and quality control in mitochondria.


Asunto(s)
Genes Mitocondriales , Mitocondrias , ARN de Transferencia , Animales , Humanos , Ratones , Células HEK293 , Mitocondrias/genética , Mitocondrias/metabolismo , Biosíntesis de Proteínas , ARN de Transferencia/metabolismo
4.
Nucleic Acids Res ; 52(9): 5226-5240, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38613394

RESUMEN

RNA acetylation is a universal post-transcriptional modification that occurs in various RNAs. Transfer RNA (tRNA) acetylation is found at position 34 (ac4C34) in bacterial tRNAMet and position 12 (ac4C12) in eukaryotic tRNASer and tRNALeu. The biochemical mechanism, structural basis and functional significance of ac4C34 are well understood; however, despite being discovered in the 1960s and identification of Kre33/NAT10 and Tan1/THUMPD1 as modifying apparatuses, ac4C12 modification activity has never been reconstituted for nearly six decades. Here, we successfully reconstituted the ac4C12 modification activity of yeast Kre33 and Tan1. Biogenesis of ac4C12 is primarily dependent on a minimal set of elements, including a canonical acceptor stem, the presence of the 11CCG13 motif and correct D-arm orientation, indicating a molecular ruler mechanism. A single A13G mutation conferred ac4C12 modification to multiple non-substrate tRNAs. Moreover, we were able to introduce ac4C modifications into small RNAs. ac4C12 modification contributed little to tRNA melting temperature and aminoacylation in vitro and in vivo. Collectively, our results realize in vitro activity reconstitution, delineate tRNA substrate selection mechanism for ac4C12 biogenesis and develop a valuable system for preparing acetylated tRNAs as well as non-tRNA RNA species, which will advance the functional interpretation of the acetylation in RNA structures and functions.


Asunto(s)
ARN de Transferencia , Proteínas de Unión al ARN , Proteínas de Saccharomyces cerevisiae , Acetilación , Mutación , Conformación de Ácido Nucleico , Procesamiento Postranscripcional del ARN , ARN de Transferencia/metabolismo , ARN de Transferencia/genética , ARN de Transferencia/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Unión al ARN/metabolismo
5.
Proc Natl Acad Sci U S A ; 120(37): e2309714120, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37669377

RESUMEN

Proofreading (editing) of mischarged tRNAs by cytoplasmic aminoacyl-tRNA synthetases (aaRSs), whose impairment causes neurodegeneration and cardiac diseases, is of high significance for protein homeostasis. However, whether mitochondrial translation needs fidelity and the significance of editing by mitochondrial aaRSs have been unclear. Here, we show that mammalian cells critically depended on the editing of mitochondrial threonyl-tRNA synthetase (mtThrRS, encoded by Tars2), disruption of which accumulated Ser-tRNAThr and generated a large abundance of Thr-to-Ser misincorporated peptides in vivo. Such infidelity impaired mitochondrial translation and oxidative phosphorylation, causing oxidative stress and cell cycle arrest in the G0/G1 phase. Notably, reactive oxygen species (ROS) scavenging by N-acetylcysteine attenuated this abnormal cell proliferation. A mouse model of heart-specific defective mtThrRS editing was established. Increased ROS levels, blocked cardiomyocyte proliferation, contractile dysfunction, dilated cardiomyopathy, and cardiac fibrosis were observed. Our results elucidate that mitochondria critically require a high level of translational accuracy at Thr codons and highlight the cellular dysfunctions and imbalance in tissue homeostasis caused by mitochondrial mistranslation.


Asunto(s)
Aminoacil-ARNt Sintetasas , Cardiomiopatías , Cardiopatías , Animales , Ratones , Especies Reactivas de Oxígeno , Puntos de Control del Ciclo Celular , Estrés Oxidativo , Mamíferos
6.
J Biol Chem ; 299(5): 104704, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37059185

RESUMEN

Aminoacyl-tRNA synthetases (aaRSs) are essential components for mRNA translation. Two sets of aaRSs are required for cytoplasmic and mitochondrial translation in vertebrates. Interestingly, TARSL2 is a recently evolved duplicated gene of TARS1 (encoding cytoplasmic threonyl-tRNA synthetase) and represents the only duplicated aaRS gene in vertebrates. Although TARSL2 retains the canonical aminoacylation and editing activities in vitro, whether it is a true tRNA synthetase for mRNA translation in vivo is unclear. In this study, we showed that Tars1 is an essential gene since homozygous Tars1 KO mice were lethal. In contrast, when Tarsl2 was deleted in mice and zebrafish, neither the abundance nor the charging levels of tRNAThrs were changed, indicating that cells relied on Tars1 but not on Tarsl2 for mRNA translation. Furthermore, Tarsl2 deletion did not influence the integrity of the multiple tRNA synthetase complex, suggesting that Tarsl2 is a peripheral member of the multiple tRNA synthetase complex. Finally, we observed that Tarsl2-deleted mice exhibited severe developmental retardation, elevated metabolic capacity, and abnormal bone and muscle development after 3 weeks. Collectively, these data suggest that, despite its intrinsic activity, loss of Tarsl2 has little influence on protein synthesis but does affect mouse development.


Asunto(s)
Aminoacil-ARNt Sintetasas , Biosíntesis de Proteínas , Treonina-ARNt Ligasa , Animales , Ratones , Aminoacil-ARNt Sintetasas/metabolismo , ARN de Transferencia/metabolismo , Treonina-ARNt Ligasa/genética , Treonina-ARNt Ligasa/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo
7.
Hum Mol Genet ; 31(4): 523-534, 2022 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-34508595

RESUMEN

TARS2 encodes human mitochondrial threonyl tRNA-synthetase that is responsible for generating mitochondrial Thr-tRNAThr and clearing mischarged Ser-tRNAThr during mitochondrial translation. Pathogenic variants in TARS2 have hitherto been reported in a pair of siblings and an unrelated patient with an early onset mitochondrial encephalomyopathy and a combined respiratory chain enzyme deficiency in muscle. We here report five additional unrelated patients with TARS2-related mitochondrial diseases, expanding the clinical phenotype to also include epilepsy, dystonia, hyperhidrosis and severe hearing impairment. In addition, we document seven novel TARS2 variants-one nonsense variant and six missense variants-that we demonstrate are pathogenic and causal of the disease presentation based on population frequency, homology modeling and functional studies that show the effects of the pathogenic variants on TARS2 stability and/or function.


Asunto(s)
Enfermedades Mitocondriales , Encefalomiopatías Mitocondriales , Treonina-ARNt Ligasa , Humanos , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/patología , Encefalomiopatías Mitocondriales/genética , Mutación , Fenotipo , ARN de Transferencia de Treonina/genética , Treonina-ARNt Ligasa/genética
8.
Opt Express ; 32(12): 21988-21995, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38859539

RESUMEN

Optical traps, including those used in atomic physics, cold chemistry, and quantum science, are widely used in the research on cold atoms and molecules. Owing to their microscopic structure and excellent operational capability, optical traps have been proposed for cold atom experiments involving complex physical systems, which generally induce violent background scattering. In this study, using a background-free imaging scheme in cavity quantum electrodynamics systems, a cold atomic ensemble was accurately prepared below a fiber cavity and loaded into an optical trap for transfer into the cavity. By satisfying the demanding requirements for the background-free imaging scheme in optical traps, cold atoms in an optical trap were detected with a high signal-to-noise ratio while maintaining atomic loading. The cold atoms were then transferred into the fiber cavity using an optical trap, and the vacuum Rabi splitting was measured, facilitating relevant research on cavity quantum electrodynamics. This method can be extended to related experiments involving cold atoms and molecules in complex physical systems using optical traps.

9.
Oecologia ; 205(1): 107-119, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38698244

RESUMEN

Community weighted mean trait, i.e., functional composition, has been extensively used for upscaling of individual traits to the community functional attributes and ecosystem functioning in recent years. Yet, the importance of intraspecific trait variation relative to species turnover in determining changes in CWM still remains unclear, especially under nutrient enrichment scenarios. In this study, we conducted a global data synthesis analysis and three nutrient addition experiments in two sites of alpine grassland to reveal the extent to which species turnover and ITV contribute to shift in CWM in response to nutrient enrichment. The results consistently show that the importance of ITV relative to species turnover in regulating CWM in response to nutrient enrichment strongly depends on trait attributes rather than on environmental factors (fertilization type, climatic factors, soil properties, and light transmittance). For whole plant traits (height) and leaf morphological traits, species turnover is generally more important than ITV in determining CWM following most treatments of nutrient addition. However, for leaf nutrient traits, ITV outweighed species turnover in determining shifts in CWM in response to almost all treatments of nutrient addition, regardless of types and gradients of the nutrient addition. Thus, our study not only provides robust evidence for trait-dependent importance of ITV in mediating community functional composition, but also highlights the need to consider the nature of functional traits in linking ITV to community assembly and ecosystem functioning under global nutrient enrichment scenarios.


Asunto(s)
Ecosistema , Nutrientes , Suelo , Hojas de la Planta , Pradera
10.
J Cutan Pathol ; 51(6): 459-467, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38443749

RESUMEN

BACKGROUND: Interstitial mycosis fungoides (IMF) is a rare subtype of mycosis fungoides (MF) characterized by atypical lymphocytes infiltrating the reticular dermis between collagen bundles with limited epidermotropism and variable granulomatous features. METHODS: Retrospective single institution review of 31 cases of IMF including clinical characteristics, disease course and pathological features. RESULTS: Our cohort was predominately male (19; 61%, M:F 1.6:1) with a mean age at diagnosis of 43 years (range 11-85), mean signs/symptoms duration of 7 years prior to diagnosis, and 6 years mean follow-up duration. Clinically, patients often exhibited symmetric ill-defined patches/plaques involving intertriginous regions with tan-yellow hyperpigmentation and follicular-based papules, wrinkling, and alopecia. Lymphadenopathy was noted in seven patients. Fifteen (52%) patients were in near or complete clinical remission at the latest follow-up. T-cell receptor gene rearrangement was positive in 23/24 (96%) cases. Histopathologically, atypical cells were small-medium, CD4+ (29; 94%) or rarely CD4+/CD8+ (1; 3%) lymphocytes infiltrating the reticular dermis with thickened collagen bundles (27; 87%), multinucleated giant cells (12; 39%), and often tracing along adnexa with subtle folliculotropism (12/20; 60%). CONCLUSIONS: Our study demonstrates IMF is an indolent subtype of MF with distinct features, including frequent granulomatous and subtle follicular involvement resulting in alopecia.


Asunto(s)
Micosis Fungoide , Neoplasias Cutáneas , Humanos , Micosis Fungoide/patología , Micosis Fungoide/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Neoplasias Cutáneas/patología , Estudios Retrospectivos , Anciano de 80 o más Años , Adolescente , Niño , Folículo Piloso/patología
11.
Nucleic Acids Res ; 50(4): 2223-2239, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35104889

RESUMEN

N 6-Threonylcarbamoyladenosine (t6A) is a universal and pivotal tRNA modification. KEOPS in eukaryotes participates in its biogenesis, whose mutations are connected with Galloway-Mowat syndrome. However, the tRNA substrate selection mechanism by KEOPS and t6A modification function in mammalian cells remain unclear. Here, we confirmed that all ANN-decoding human cytoplasmic tRNAs harbor a t6A moiety. Using t6A modification systems from various eukaryotes, we proposed the possible coevolution of position 33 of initiator tRNAMet and modification enzymes. The role of the universal CCA end in t6A biogenesis varied among species. However, all KEOPSs critically depended on C32 and two base pairs in the D-stem. Knockdown of the catalytic subunit OSGEP in HEK293T cells had no effect on the steady-state abundance of cytoplasmic tRNAs but selectively inhibited tRNAIle aminoacylation. Combined with in vitro aminoacylation assays, we revealed that t6A functions as a tRNAIle isoacceptor-specific positive determinant for human cytoplasmic isoleucyl-tRNA synthetase (IARS1). t6A deficiency had divergent effects on decoding efficiency at ANN codons and promoted +1 frameshifting. Altogether, our results shed light on the tRNA recognition mechanism, revealing both commonality and diversity in substrate recognition by eukaryotic KEOPSs, and elucidated the critical role of t6A in tRNAIle aminoacylation and codon decoding in human cells.


Asunto(s)
Eucariontes , ARN de Transferencia de Isoleucina , Adenosina/genética , Animales , Codón , Eucariontes/genética , Células HEK293 , Humanos , Mamíferos/genética , Conformación de Ácido Nucleico , ARN de Transferencia/genética , ARN de Transferencia de Metionina
12.
Nucleic Acids Res ; 50(20): 11755-11774, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36350636

RESUMEN

Mitochondrial translation is of high significance for cellular energy homeostasis. Aminoacyl-tRNA synthetases (aaRSs) are crucial translational components. Mitochondrial aaRS variants cause various human diseases. However, the pathogenesis of the vast majority of these diseases remains unknown. Here, we identified two novel SARS2 (encoding mitochondrial seryl-tRNA synthetase) variants that cause a multisystem disorder. c.654-14T > A mutation induced mRNA mis-splicing, generating a peptide insertion in the active site; c.1519dupC swapped a critical tRNA-binding motif in the C-terminus due to stop codon readthrough. Both mutants exhibited severely diminished tRNA binding and aminoacylation capacities. A marked reduction in mitochondrial tRNASer(AGY) was observed due to RNA degradation in patient-derived induced pluripotent stem cells (iPSCs), causing impaired translation and comprehensive mitochondrial function deficiencies. These impairments were efficiently rescued by wild-type SARS2 overexpression. Either mutation caused early embryonic fatality in mice. Heterozygous mice displayed reduced muscle tissue-specific levels of tRNASers. Our findings elucidated the biochemical and cellular consequences of impaired translation mediated by SARS2, suggesting that reduced abundance of tRNASer(AGY) is a key determinant for development of SARS2-related diseases.


Asunto(s)
Aminoacil-ARNt Sintetasas , COVID-19 , Serina-ARNt Ligasa , Humanos , Ratones , Animales , ARN de Transferencia de Serina/genética , Serina-ARNt Ligasa/genética , Serina-ARNt Ligasa/metabolismo , Aminoacil-ARNt Sintetasas/genética , Aminoacilación
13.
Nucleic Acids Res ; 50(22): 12951-12968, 2022 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-36503967

RESUMEN

Mitochondrial RNA metabolism is suggested to occur in identified compartmentalized foci, i.e. mitochondrial RNA granules (MRGs). Mitochondrial aminoacyl-tRNA synthetases (mito aaRSs) catalyze tRNA charging and are key components in mitochondrial gene expression. Mutations of mito aaRSs are associated with various human disorders. However, the suborganelle distribution, interaction network and regulatory mechanism of mito aaRSs remain largely unknown. Here, we found that all mito aaRSs partly colocalize with MRG, and this colocalization is likely facilitated by tRNA-binding capacity. A fraction of human mitochondrial AlaRS (hmtAlaRS) and hmtSerRS formed a direct complex via interaction between catalytic domains in vivo. Aminoacylation activities of both hmtAlaRS and hmtSerRS were fine-tuned upon complex formation in vitro. We further established a full spectrum of interaction networks via immunoprecipitation and mass spectrometry for all mito aaRSs and discovered interactions between hmtSerRS and hmtAsnRS, between hmtSerRS and hmtTyrRS and between hmtThrRS and hmtArgRS. The activity of hmtTyrRS was also influenced by the presence of hmtSerRS. Notably, hmtSerRS utilized the same catalytic domain in mediating several interactions. Altogether, our results systematically analyzed the suborganelle localization and interaction network of mito aaRSs and discovered several mito aaRS-containing complexes, deepening our understanding of the functional and regulatory mechanisms of mito aaRSs.


Asunto(s)
Aminoacil-ARNt Sintetasas , Aminoacilación de ARN de Transferencia , Humanos , Aminoacil-ARNt Sintetasas/metabolismo , Gránulos de Ribonucleoproteínas Citoplasmáticas/metabolismo , ARN Mitocondrial/metabolismo , ARN de Transferencia/metabolismo
14.
Nucleic Acids Res ; 50(7): 4012-4028, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35357504

RESUMEN

METTL8 has recently been identified as the methyltransferase catalyzing 3-methylcytidine biogenesis at position 32 (m3C32) of mitochondrial tRNAs. METTL8 also potentially participates in mRNA methylation and R-loop biogenesis. How METTL8 plays multiple roles in distinct cell compartments and catalyzes mitochondrial tRNA m3C formation remain unclear. Here, we discovered that alternative mRNA splicing generated several isoforms of METTL8. One isoform (METTL8-Iso1) was targeted to mitochondria via an N-terminal pre-sequence, while another one (METTL8-Iso4) mainly localized to the nucleolus. METTL8-Iso1-mediated m3C32 modification of human mitochondrial tRNAThr (hmtRNAThr) was not reliant on t6A modification at A37 (t6A37), while that of hmtRNASer(UCN) critically depended on i6A modification at A37 (i6A37). We clarified the hmtRNAThr substrate recognition mechanism, which was obviously different from that of hmtRNASer(UCN), in terms of requiring a G35 determinant. Moreover, SARS2 (mitochondrial seryl-tRNA synthetase) interacted with METTL8-Iso1 in an RNA-independent manner and modestly accelerated m3C modification activity. We further elucidated how nonsubstrate tRNAs in human mitochondria were efficiently discriminated by METTL8-Iso1. In summary, our results established the expression pattern of METTL8, clarified the molecular basis for m3C32 modification by METTL8-Iso1 and provided the rationale for the involvement of METTL8 in tRNA modification, mRNA methylation or R-loop biogenesis.


Asunto(s)
Metiltransferasas/metabolismo , Mitocondrias/metabolismo , ARN de Transferencia , Empalme Alternativo , Humanos , Metiltransferasas/genética , Mitocondrias/genética , ARN Mensajero , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , ARN de Transferencia de Treonina/genética
15.
Sensors (Basel) ; 24(5)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38475056

RESUMEN

In this paper, an improved APF-GFARRT* (artificial potential field-guided fuzzy adaptive rapidly exploring random trees) algorithm based on APF (artificial potential field) guided sampling and fuzzy adaptive expansion is proposed to solve the problems of weak orientation and low search success rate when randomly expanding nodes using the RRT (rapidly exploring random trees) algorithm for disinfecting robots in the dense environment of disinfection operation. Considering the inherent randomness of tree growth in the RRT* algorithm, a combination of APF with RRT* is introduced to enhance the purposefulness of the sampling process. In addition, in the context of RRT* facing dense and restricted environments such as narrow passages, adaptive step-size adjustment is implemented using fuzzy control. It accelerates the algorithm's convergence and improves search efficiency in a specific area. The proposed algorithm is validated and analyzed in a specialized environment designed in MATLAB, and comparisons are made with existing path planning algorithms, including RRT, RRT*, and APF-RRT*. Experimental results show the excellent exploration speed of the improved algorithm, reducing the average initial path search time by about 46.52% compared to the other three algorithms. In addition, the improved algorithm exhibits faster convergence, significantly reducing the average iteration count and the average final path cost by about 10.01%. The algorithm's enhanced adaptability in unique environments is particularly noteworthy, increasing the chances of successfully finding paths and generating more rational and smoother paths than other algorithms. Experimental results validate the proposed algorithm as a practical and feasible solution for similar problems.

16.
Molecules ; 29(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38611780

RESUMEN

This study investigates the synthesis of mesophase pitch using low-cost fluid catalytic cracking (FCC) slurry and waste fluid asphaltene (WFA) as raw materials through the co-carbonization method. The resulting mesophase pitch product and its formation mechanism were thoroughly analyzed. Various characterization techniques, including polarizing microscopy, softening point measurement, Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), were employed to characterize and analyze the properties and structure of the mesophase pitch. The experimental results demonstrate that the optimal optical texture of the mesophase product is achieved under specific reaction conditions, including a temperature of 420 °C, pressure of 1 MPa, reaction time of 6 h, and the addition of 2% asphaltene. It was observed that a small amount of asphaltene contributes to the formation of mesophase pitch spheres, facilitating the development of the mesophase. However, excessive content of asphaltene may cover the surface of the mesophase spheres, impeding the contact between them and consequently compromising the optical texture of the mesophase pitch product. Furthermore, the inclusion of asphaltene promotes polymerization reactions in the system, leading to an increase in the average molecular weight of the mesophase pitch. Notably, when the amount of asphaltene added is 2%, the mesophase pitch demonstrates the lowest ID/IG value, indicating superior molecular orientation and larger graphite-like microcrystals. Additionally, researchers found that at this asphaltene concentration, the mesophase pitch exhibits the highest degree of order, as evidenced by the maximum diffraction angle (2θ) and stacking height (Lc) values, and the minimum d002 value. Moreover, the addition of asphaltene enhances the yield and aromaticity of the mesophase pitch and significantly improves the thermal stability of the resulting product.

17.
J Sci Food Agric ; 104(5): 3069-3079, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38072654

RESUMEN

BACKGROUND: ε-polylysine hydrochloride (ε-PLH) is a naturally occurring antimicrobial peptide extensively utilized in the food and medical industries. However, its impact on animal husbandry remains to be further explored. Therefore, the present study aimed to determine the effect of ε-PLH on laying hens' health and laying performance. RESULTS: Dietary supplementation with ε-PLH to the diet significantly increased average egg weight during weeks 1-8. Meanwhile, compared with the control group, supplementation with ε-PLH decreased the feed egg ratio during weeks 9-12 and egg breakage rate during weeks 9-16 ,whereas it increased eggshell strength during weeks 1-4 and 13-16 . The ε-PLH 0.05% group increased yolk percentage during weeks 5-8 and yolk color during weeks 1-4 . Furthermore, ε-PLH supplementation significantly increased the concentrations of total protein, albumin, globulin and reproductive hormones estradiol, as well as decreased interleukin-1 beta and malondialdehyde in the serum. Compared with the control group, supplementation with 0.05% ε-PLH significantly increased the relative abundance of Cyanobacteria and Gastranaerophilales and decreased the abundance of Desulfovibrio and Streptococcus in the cecum microbiota. In addition, ε-PLH 0.1% supplementation also increased acetic acid content in the cecum. CONCLUSION: Dietary supplementation with ε-PLH has a positive impact on both productive performance and egg quality in laying hens. Furthermore, ε-PLH can also relieve inflammation by promoting the immunity and reducing oxidative damage during egg production. ε-PLH has been shown to improve intestinal morphology, gut microbial diversity and intestinal health. © 2023 Society of Chemical Industry.


Asunto(s)
Microbioma Gastrointestinal , Animales , Femenino , Polilisina/farmacología , Pollos/microbiología , Suplementos Dietéticos/análisis , Dieta/veterinaria , Ácidos Grasos Volátiles , Alimentación Animal/análisis
18.
Plant Biotechnol J ; 21(6): 1159-1175, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36752567

RESUMEN

Grain size and filling are two key determinants of grain thousand-kernel weight (TKW) and crop yield, therefore they have undergone strong selection since cereal was domesticated. Genetic dissection of the two traits will improve yield potential in crops. A quantitative trait locus significantly associated with wheat grain TKW was detected on chromosome 7AS flanked by a simple sequence repeat marker of Wmc17 in Chinese wheat 262 mini-core collection by genome-wide association study. Combined with the bulked segregant RNA-sequencing (BSR-seq) analysis of an F2 genetic segregation population with extremely different TKW traits, a candidate trehalose-6-phosphate phosphatase gene located at 135.0 Mb (CS V1.0), designated as TaTPP-7A, was identified. This gene was specifically expressed in developing grains and strongly influenced grain filling and size. Overexpression (OE) of TaTPP-7A in wheat enhanced grain TKW and wheat yield greatly. Detailed analysis revealed that OE of TaTPP-7A significantly increased the expression levels of starch synthesis- and senescence-related genes involved in abscisic acid (ABA) and ethylene pathways. Moreover, most of the sucrose metabolism and starch regulation-related genes were potentially regulated by SnRK1. In addition, TaTPP-7A is a crucial domestication- and breeding-targeted gene and it feedback regulates sucrose lysis, flux, and utilization in the grain endosperm mainly through the T6P-SnRK1 pathway and sugar-ABA interaction. Thus, we confirmed the T6P signalling pathway as the central regulatory system for sucrose allocation and source-sink interactions in wheat grains and propose that the trehalose pathway components have great potential to increase yields in cereal crops.


Asunto(s)
Ácido Abscísico , Grano Comestible , Ácido Abscísico/metabolismo , Grano Comestible/genética , Grano Comestible/metabolismo , Triticum/genética , Triticum/metabolismo , Azúcares/metabolismo , Retroalimentación , Estudio de Asociación del Genoma Completo , Fitomejoramiento , Sacarosa/metabolismo , Almidón/metabolismo
19.
Virol J ; 20(1): 280, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38031162

RESUMEN

BACKGROUND: Promyelocytic leukemia protein (PML) is a primary component of PML nuclear bodies (PML-NBs). PML and PML-NBs play critical roles in processes like the cell cycle, DNA damage repair, apoptosis, and the antiviral immune response. Previously, we identified five porcine PML alternative splicing variants and observed an increase in the expression of these PML isoforms following Japanese encephalitis virus (JEV) infection. In this study, we examined the functional roles of these PML isoforms in JEV infection. METHODS: PML isoforms were either knocked down or overexpressed in PK15 cells, after which they were infected with JEV. Subsequently, we analyzed the gene expression of PML isoforms, JEV, and the interferon (IFN)-ß signaling pathway using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. Viral titers were determined through 50% tissue culture infectious dose (TCID50) assays. RESULTS: Our results demonstrated that the knockdown of endogenous PML promoted JEV replication, while the overexpression of PML isoforms 1, 3, 4, and 5 (PML1, PML3, PML4, and PML5) inhibited JEV replication. Further investigation revealed that PML1, PML3, PML4, and PML5 negatively regulated the expression of genes involved in the interferon (IFN)-ß signaling pathway by inhibiting IFN regulatory factor 3 (IRF3) post-JEV infection. CONCLUSIONS: These findings demonstrate that porcine PML isoforms PML1, PML3, PML4, and PML5 negatively regulate IFN-ß and suppress viral replication during JEV infection. The results of this study provide insight into the functional roles of porcine PML isoforms in JEV infection and the regulation of the innate immune response.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Animales , Porcinos , Proteína de la Leucemia Promielocítica/genética , Proteína de la Leucemia Promielocítica/metabolismo , Factores de Transcripción/genética , Interferones , Isoformas de Proteínas/genética , Replicación Viral
20.
J Am Acad Dermatol ; 88(3): 623-631, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36528266

RESUMEN

Rapid human-to-human transmission of monkeypox has created a public health emergency requiring prompt, multidisciplinary attention. Dermatologists are at the forefront of diagnosis due to the disease-defining skin lesions. Moreover, patients with pre-existing skin disease and those who are on immunosuppressive medications for skin disease may be at increased risk of severe infection. In this review, a panel of authors with expertise in complex medical dermatology and managing patients on immunosuppression reviews the literature and provides initial guidance for diagnosis and management in dermatology practices. Though there are knowledge gaps due to a lack of controlled studies, we support use of replication-deficit vaccines in all dermatologic patients who meet qualifying risk or exposure criteria. We offer strategies to optimize vaccine efficacy in patients with immunosuppression. We discuss alternative post-exposure treatments and their safety profiles. Finally, we outline supportive care recommendations for cutaneous manifestations of monkeypox. Large scale epidemiologic investigations and clinical trials will ultimately revise and extend our guidance.


Asunto(s)
Dermatología , Mpox , Enfermedades de la Piel , Humanos , Mpox/epidemiología , Vacunación , Brotes de Enfermedades , Enfermedades de la Piel/diagnóstico
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