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1.
Plant Cell ; 35(12): 4199-4216, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37647532

RESUMEN

Breeding has dramatically changed the plant architecture of wheat (Triticum aestivum), resulting in the development of high-yielding varieties adapted to modern farming systems. However, how wheat breeding shaped the genomic architecture of this crop remains poorly understood. Here, we performed a comprehensive comparative analysis of a whole-genome resequencing panel of 355 common wheat accessions (representing diverse landraces and modern cultivars from China and the United States) at the phenotypic and genomic levels. The genetic diversity of modern wheat cultivars was clearly reduced compared to landraces. Consistent with these genetic changes, most phenotypes of cultivars from China and the United States were significantly altered. Of the 21 agronomic traits investigated, 8 showed convergent changes between the 2 countries. Moreover, of the 207 loci associated with these 21 traits, more than half overlapped with genomic regions that showed evidence of selection. The distribution of selected loci between the Chinese and American cultivars suggests that breeding for increased productivity in these 2 regions was accomplished by pyramiding both shared and region-specific variants. This work provides a framework to understand the genetic architecture of the adaptation of wheat to diverse agricultural production environments, as well as guidelines for optimizing breeding strategies to design better wheat varieties.


Asunto(s)
Genoma de Planta , Triticum , Estados Unidos , Triticum/genética , Genoma de Planta/genética , Fitomejoramiento , Fenotipo , China , Variación Genética
2.
Mol Biol Evol ; 40(2)2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36718535

RESUMEN

The genetic basis of phenotypic variation is a long-standing concern of evolutionary biology. Coloration has proven to be a visual, easily quantifiable, and highly tractable system for genetic analysis and is an ever-evolving focus of biological research. Compared with the homogenized brown-yellow cocoons of wild silkworms, the cocoons of domestic silkworms are spectacularly diverse in color, such as white, green, and yellow-red; this provides an outstanding model for exploring the phenotypic diversification and biological coloration. Herein, the molecular mechanism underlying silkworm green cocoon formation was investigated, which was not fully understood. We demonstrated that five of the seven members of a sugar transporter gene cluster were specifically duplicated in the Bombycidae and evolved new spatial expression patterns predominantly expressed in silk glands, accompanying complementary temporal expression; they synergistically facilitate the uptake of flavonoids, thus determining the green cocoon. Subsequently, polymorphic cocoon coloring landscape involving multiple loci and the evolution of cocoon color from wild to domestic silkworms were analyzed based on the pan-genome sequencing data. It was found that cocoon coloration involved epistatic interaction between loci; all the identified cocoon color-related loci existed in wild silkworms; the genetic segregation, recombination, and variation of these loci shaped the multicolored cocoons of domestic silkworms. This study revealed a new mechanism for flavonoids-based biological coloration that highlights the crucial role of gene duplication followed by functional diversification in acquiring new genetic functions; furthermore, the results in this work provide insight into phenotypic innovation during domestication.


Asunto(s)
Bombyx , Animales , Bombyx/genética , Bombyx/metabolismo , Seda/genética , Seda/metabolismo , Secuencia de Bases , Flavonoides/metabolismo
3.
Anal Biochem ; 692: 115548, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38697593

RESUMEN

Oviductus Ranae is the dried oviduct from Rana dybowskii, a forest frog species with medicinal, tonic, and cosmetic properties. Due to the high price and resource shortage, counterfeit varieties of Oviductus Ranae often appear in the market. However, traditional identification methods cannot accurately differentiate between Oviductus Ranae and its adulterants. In this study, a rapid molecular identification method has been established. The method involves extracting genomic DNA in just 30 s using filter paper purification, species-specific rapid polymerase chain reaction (PCR) amplification, and finally, fluorescence detection of the products. It can accurately identify Oviductus Ranae and its three common adulterants in about 30 min, making the process simple, fast, and highly specific.


Asunto(s)
Cartilla de ADN , Reacción en Cadena de la Polimerasa , Ranidae , Especificidad de la Especie , Animales , Ranidae/genética , Reacción en Cadena de la Polimerasa/métodos , Femenino , Oviductos/metabolismo , ADN/análisis , ADN/genética , ADN/aislamiento & purificación
4.
Angew Chem Int Ed Engl ; : e202408918, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013139

RESUMEN

The excessive and prolonged use of antibiotics contributes to the emergence of drug-resistant S. aureus strains and potential dysbacteriosis-related diseases, necessitating the exploration of alternative therapeutic approaches. Herein, we present a light-activated nanocatalyst for synthesizing in-situ antimicrobials through photoredox-catalytic click reaction, achieving precise, site-directed elimination of S. aureus skin infections. Methylene blue (MB), a commercially available photosensitizer, was encapsulated within the CuII-based metal-organic framework, MOF-199, and further enveloped with Pluronic F-127 to create the light-responsive nanocatalyst MB@PMOF. Upon exposure to red light, MB participates in a photoredox-catalytic cycle, driven by the 1,3,5-benzenetricarboxylic carboxylate salts (BTC-) ligand presented in the structure of MOF-199. This light-activated MB then catalyzes the reduction of CuII to CuI through a single-electron transfer (SET) process, efficiently initiating the click reaction to form active antimicrobial agents under physiological conditions. Both in vitro and in vivo results demonstrated the effectiveness of MB@PMOF-catalyzed drug synthesis in inhibiting S. aureus, including their methicillin-resistant strains, thereby accelerating skin healing in severe bacterial infections. This study introduces a novel design paradigm for controlled, on-site drug synthesis, offering a promising alternative to realize precise treatment of bacterial infections without undesirable side effects.

5.
Org Biomol Chem ; 21(23): 4823-4832, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37249008

RESUMEN

A novel visible-light induced sulfonylation/ipso-cyclization of N-arylpropiolamides with cyclobutanone oxime esters and Na2S2O5 was reported. This protocol proceeded via a radical process. The wide substrate scope, sustainable metal-free conditions and readily accessible reagents make this protocol an efficient and green strategy for the synthesis of cyanoalkyl sulfonated spiro[4,5]trienones.

6.
J Clin Lab Anal ; 36(10): e24683, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36059119

RESUMEN

OBJECT: The aim of the present work was to investigate the correlation of plasma platelet-derived growth factor (PDGF)-BB level and single nucleotide polymorphism (SNP, rs1800817 and rs2285094) of PDGF-B gene with the onset and stability condition of coronary heart disease (CHD). METHODS: Totally, 335 subjects were included in and divided into CHD (n = 247) and control group (n = 88) according to coronary angiography. Besides, the patients in the CHD group were divided into acute coronary syndrome (ACS) group (n = 165) and stable angina pectoria (SAP) group (n = 82), based on CHD stability condition. The plasma PDGF-BB level was measured by ELISA, and the genotype of PDGF-B was examined through qPCR assay. RESULTS: The PDGF-BB level was positively correlated with hsCRP level (r = 0.149, p < 0.05). The genotype frequencies of SNP rs1800817 and rs2285094 match Hardy-Weinberg equilibrium. There was weak linkage disequilibrium between SNP rs1800817 and rs2285094: D' = 0.419, r2  = 0.04, which has no correlation with CHD. There was no statistical difference in plasma PDGF-BB level among different genotypes in rs1800817 and rs2285094. There were no differences in the plasma PDGF-BB level among patients with any genotype of SNP rs1800817 and rs2285094, no matter how it was grouped. Logistic regression results indicated that the plasma PDGF-BB level was the independent risk factor of CHD onset (OR = 1.003, 95% CI 1.001-1.006, p = 0.014). CONCLUSIONS: High plasma PDGF-BB level is the risk factor of CHD and has correlation with instability of CHD. The plasma PDGF-BB level change may be related to inflammatory response. PDGF-B gene rs1800817 and rs2285094 polymorphisms are not correlated with CHD.


Asunto(s)
Enfermedad Coronaria , Infarto del Miocardio , Becaplermina/genética , Proteína C-Reactiva , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/genética , Humanos , Polimorfismo de Nucleótido Simple/genética
7.
Int J Mol Sci ; 23(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35409210

RESUMEN

The insect glycoside hydrolase family 20 ß-N-acetylhexosaminidases (HEXs) are key enzymes involved in chitin degradation. In this study, nine HEX genes in Bombyx mori were identified by genome-wide analysis. Bioinformatic analysis based on the transcriptome database indicated that each gene had a distinct expression pattern. qRT-PCR was performed to detect the expression pattern of the chitooligosaccharidolytic ß-N-acetylglucosaminidase (BmChiNAG). BmChiNAG was highly expressed in chitin-rich tissues, such as the epidermis. In the wing disc and epidermis, BmChiNAG has the highest expression level during the wandering stage. CRISPR/Cas9-mediated BmChiNAG deletion was used to study the function. In the BmChiNAG-knockout line, 39.2% of female heterozygotes had small and curly wings. The ultrastructure of a cross-section showed that the lack of BmChiNAG affected the stratification of the wing membrane and the formation of the correct wing vein structure. The molting process of the homozygotes was severely hindered during the larva to pupa transition. Epidermal sections showed that the endocuticle of the pupa was not degraded in the mutant. These results indicate that BmChiNAG is involved in chitin catabolism and plays an important role in the molting and wing development of the silkworm, which highlights the potential of BmChiNAG as a pest control target.


Asunto(s)
Bombyx , Animales , Bombyx/metabolismo , Quitina/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Larva/genética , Larva/metabolismo , Muda/genética , Pupa
8.
Clin Immunol ; 216: 108462, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32437925

RESUMEN

Acetylcholine receptor (AChR)-specific CD4+ T cells play a driving role in myasthenia gravis (MG) by regulating the production of autoantibodies. However, the quantitative features of AChR-specific T cells and their clinical significance in MG are unclear. In this study, we adopted standard and cultured enzyme-linked immunosorbent spot (ELISPOT) assays to quantify subpopulations of AChR-specific CD4+ T cells in MG patients, and evaluate their correlation with clinical characteristics. The results showed that Th1- and Th17-AChR-specific CD4+ T cells were detectable by standard and cultured ELISPOT assay respectively, with higher levels observed in MG patients comparing with healthy controls. The number of Th17-AChR-specific CD4+ T cells was positively correlated with anti-AChR antibody titer and quantitative MG score and may have latent capacity to reflect responses to immunosuppressants. These results highlight the differences in quantitative features of AChR-specific CD4+ T cells and imply Th17-AChR-specific CD4+ T cells can serve as a biomarker in MG.


Asunto(s)
Acetilcolina/inmunología , Linfocitos T CD4-Positivos/inmunología , Miastenia Gravis/inmunología , Receptores Colinérgicos/inmunología , Adolescente , Adulto , Autoanticuerpos/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Células TH1/inmunología , Células Th17/inmunología , Adulto Joven
9.
Clin Immunol ; 218: 108492, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32526271

RESUMEN

Interleukin-17-expressing CD4+ T helper 17 (Th17) cells are considered to be critical regulators of thymic inflammation in AChR-MG patients. However, Th17 cells are functionally heterogeneous and circulating Th17 subsets are incompletely understood in AChR-MG patients. Here, we studied characteristics of Th17 subsets in peripheral blood from treatment-naïve AChR-MG patients, patients treated with immunosuppressants, as well as healthy controls. We found increased frequencies of circulating Th1-like Th17 (Th1/17) (IFN-γ + IL-17 + CD4 + CD3+) cells, which declined earlier than conventional Th17 (IFN-γ - IL-17 + CD4 + CD3+) cells in patients who respond well to immunosuppression treatment. Additionally, circulating Th1/17 cell frequencies were found to correlate positively with disease severity. Further, compared to conventional Th17 cells, Th1/17 cells showed an elevated expression of IFNG, TBX21, IL23R, CSF2, and a reduced expression of AHR and IL10. Taken together, our results suggest circulating Th1/17 cells may serve as a biomarker of disease severity and provide a strong rationale for early intervention in AChR-MG patients.


Asunto(s)
Miastenia Gravis/inmunología , Células TH1/inmunología , Células Th17/inmunología , Adulto , Biomarcadores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores Colinérgicos , Índice de Severidad de la Enfermedad
10.
J Integr Plant Biol ; 62(12): 1925-1941, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32584503

RESUMEN

Iron is an essential microelement for plant growth. After uptake from the soil, iron is chelated by ligands and translocated from roots to shoots for subsequent utilization. However, the number of ligands involved in iron chelation is unclear. In this study, we identified and demonstrated that GLU1, which encodes a ferredoxin-dependent glutamate synthase, was involved in iron homeostasis. First, the expression of GLU1 was strongly induced by iron deficiency condition. Second, lesion of GLU1 results in reduced transcription of many iron-deficiency-responsive genes in roots and shoots. The mutant plants revealed a decreased iron concentration in the shoots, and displayed severe leaf chlorosis under the condition of Fe limitation, compared to wild-type. Third, the product of GLU1, glutamate, could chelate iron in vivo and promote iron transportation. Last, we also found that supplementation of glutamate in the medium can alleviate cadmium toxicity in plants. Overall, our results provide evidence that GLU1 is involved in iron homeostasis through affecting glutamate synthesis under iron deficiency conditions in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Glutamato Sintasa/metabolismo , Deficiencias de Hierro , Hierro/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Glutamato Sintasa/genética , Ácido Glutámico/metabolismo
11.
Infect Immun ; 87(11)2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31427452

RESUMEN

Eimeria tenella microneme-1 protein (EtMIC1) has been proposed to be a transmembrane protein, but this characteristic has not yet been confirmed experimentally. Furthermore, despite EtMIC1 being an important candidate antigen, its key epitope has not been reported. Here, two linear B-cell epitopes of EtMIC1, 91LITFATRSK99 and 698ESLISAGE705, were identified by Western blotting using specific monoclonal antibodies (MAbs) and were named epitope I (located in the I-domain) and epitope CTR (located in the CTR domain), respectively. Sequence comparative analyses of these epitopes among Eimeria species that infect chickens showed that epitope I differs greatly across species, whereas epitope CTR is relatively conserved. Point mutation assay results indicate that all the amino acid residues of the epitopes recognized by MAb 1-A1 or 1-H2 are key amino acids involved in recognition. Comparative analyses of indirect immunofluorescence assay (IFA) results for MAbs 1-A1 and 1-H2 under both nonpermeabilization and permeabilization conditions indicate that epitope I is located on the outer side of the sporozoite surface membrane whereas epitope CTR is located on the inner side, together providing experimental evidence that EtMIC1 is a transmembrane protein. IFA also labeled the EtMIC1 protein on the parasitophorous vacuole membrane and on the surface of schizonts, which suggests that the EtMIC1 protein may play an important role in parasitophorous vacuole formation and E. tenella development. Immunoprotective efficacy experiments revealed that epitope I has good immunogenicity, as evidenced by its induction of high serum antibody levels, blood lymphocyte proliferation, and CD4+ blood lymphocyte percentage.


Asunto(s)
Anticuerpos Monoclonales , Eimeria tenella/metabolismo , Epítopos , Proteínas Protozoarias/metabolismo , Animales , Anticuerpos Antiprotozoarios , Antígenos de Protozoos/inmunología , Pollos , Coccidiosis/inmunología , Coccidiosis/parasitología , Coccidiosis/veterinaria , Eimeria tenella/genética , Ratones , Ratones Endogámicos BALB C , Enfermedades de las Aves de Corral/inmunología , Proteínas Protozoarias/química , Proteínas Protozoarias/genética
12.
Anal Chem ; 91(17): 11397-11402, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31402659

RESUMEN

Hydroxylamine (HA) is an important product of cell metabolism and plays a significant role in many biological processes, and therefore, real-time imaging of HA is of great importance for the in-depth study of its physiological and pathological functions. However, a HA-specific fluorescent probe is currently lacking primarily because the highly selective HA-responsive site is undeveloped. To address this critical issue, we present a HA-specific FRET-based fluorescent probe (RhChr) for the selective detection of HA in living systems. Inspired by aza-Michael addition, the unsaturated system appended with an iminium ion was employed as the new HA-specific response site. In response to HA, RhChr provided a ratiometric signal output with excellent selectivity toward HA over biothiols and ammonia. We have demonstrated that RhChr could be applied for the ratiometric imaging of endogenous HA in living cells and the evaluation of xanthine oxidase (XOD) activity in living organs.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes , Hidroxilamina/análisis , Imagen Molecular/métodos , Imagen Óptica/métodos , Animales , Supervivencia Celular , Células Cultivadas , Humanos , Xantina Oxidasa/metabolismo
13.
Anal Chem ; 91(9): 5513-5516, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-31014068

RESUMEN

Cysteine (Cys) is an important mediator to regulate the redox state of endoplasmic reticulum (ER), and its level is closely related with many ER stress induced serious diseases. Herein, we present an ER-specific fluorescent probe for the ratiometric imaging of cellular Cys for the first time. The probe exhibited desirable selectivity and sensitivity to Cys. Biological imaging experiments demonstrated that the probe possessed an ER-targeting property, showed ratiometric response to Cys in ER, and could be applied for the ratiometric imaging of Cys level changes during H2O2-induced redox imbalance in living cells.


Asunto(s)
Cistina/metabolismo , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Peróxido de Hidrógeno/farmacología , Cistina/química , Colorantes Fluorescentes/química , Células HeLa , Humanos , Oxidación-Reducción/efectos de los fármacos
14.
Analyst ; 144(14): 4371-4379, 2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31197299

RESUMEN

SO2 has been recently identified as an essential gas messenger followed by NO, CO and H2S. However, abnormal concentrations of SO2 in our bodies can cause many diseases. Thus, the real-time monitoring of SO2 to well define the generation, physiological and pathological functions of SO2 is urgently needed. In this work, we developed a novel SO2 fluorescent probe on the basis of the conjugation of semi-cyanine and coumarin derivate dyes with superior features, such as near-infrared (NIR) and two-photon dual-mode monitoring, a large Stokes shift (175 nm), ultrafast response towards SO2 (within 10 s), high selectivity and photostability. Furthermore, this probe could sense SO2 by dual colorimetric and fluorescence means. In biological imaging, the probe was able to trace exogenous and endogenous SO2 in living cells, mitochondria, E. coli, zebrafish and mice under an NIR and two-photon dual-mode. These results demonstrated that the probe has strong potential for studying the physiological and pathological functions of SO2in vitro and in vivo.


Asunto(s)
Cumarinas/química , Colorantes Fluorescentes/química , Indoles/química , Dióxido de Azufre/análisis , Animales , Colorimetría/métodos , Cumarinas/síntesis química , Cumarinas/efectos de la radiación , Cumarinas/toxicidad , Escherichia coli , Femenino , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/efectos de la radiación , Colorantes Fluorescentes/toxicidad , Células Hep G2 , Humanos , Indoles/síntesis química , Indoles/efectos de la radiación , Indoles/toxicidad , Ratones Endogámicos BALB C , Microscopía Fluorescente/métodos , Imagen Óptica/métodos , Fotones , Pez Cebra
15.
Plant Cell ; 27(3): 649-62, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25757472

RESUMEN

Organ growth involves the coordination of cell proliferation and cell growth with differentiation. Endoreduplication is correlated with the onset of cell differentiation and with cell and organ size, but little is known about the molecular mechanisms linking cell and organ growth with endoreduplication. We have previously demonstrated that the ubiquitin receptor DA1 influences organ growth by restricting cell proliferation. Here, we show that DA1 and its close family members DAR1 and DAR2 are redundantly required for endoreduplication during leaf development. DA1, DAR1, and DAR2 physically interact with the transcription factors TCP14 and TCP15, which repress endoreduplication by directly regulating the expression of cell-cycle genes. We also show that DA1, DAR1, and DAR2 modulate the stability of TCP14 and TCP15 proteins in Arabidopsis thaliana. Genetic analyses demonstrate that DA1, DAR1, and DAR2 function in a common pathway with TCP14/15 to regulate endoreduplication. Thus, our findings define an important genetic and molecular mechanism involving the ubiquitin receptors DA1, DAR1, and DAR2 and the transcription factors TCP14 and TCP15 that links endoreduplication with cell and organ growth.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Endorreduplicación , Ubiquitina/metabolismo , Secuencias de Aminoácidos , Proteínas de Unión al ADN/metabolismo , Proteínas con Dominio LIM/metabolismo , Modelos Biológicos , Especificidad de Órganos , Desarrollo de la Planta , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Unión Proteica , Estabilidad Proteica , Factores de Transcripción/metabolismo
16.
Life Sci ; 336: 122287, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37995933

RESUMEN

BACKGROUND: Cells and tissues in an inflammatory state are usually hypoxic. The hypoxic environment can affect the differentiation of immune cells and produce Hypoxia-inducible Factor-1α (HIF-1α). Inflammation is also a major contributor to the development and deterioration of Myasthenia Gravis (MG). There are limited studies on the immunopathological mechanism and targeted therapy associated with MG exacerbated with inflammation. This research aimed to explore whether BAY 87-2243 (HIF-1α inhibitor) ameliorates the symptoms of the Experimental Autoimmune Myasthenia Gravis (EAMG) inflammation model and study its regulatory mechanism on cellular immunity and humoral immunity. METHODS: We first establish the EAMG inflammation model using Lipopolysaccharide (LPS), BAY 87-2243 was applied to the EAMG inflammation model and its therapeutic effects were evaluated in vivo and in vitro experiments. RESULTS: The proportion of Treg cells was increased whereas Th1, Th17, and Th1/17 cells were decreased in BAY 87-2243-treated EAMG inflammation model. BAY 87-2243 ameliorated the acetylcholine receptors (AChRs) loss and the complement deposited at the neuromuscular junction of the EAMG inflammation model, declined the levels of IFN-γ, IL-17, and IL-6 in serum, and further attenuated responses in the germinal center and reduced the antibody levels by inhibiting the IL-6-dependent STAT3 axis. CONCLUSION: BAY 87-2243 restored the balance of CD4+T cell subsets and reduced the production of the pro-inflammatory cytokines, thus acting as both an immune imbalance regulator and anti-inflammatory. The current study suggests that HIF-1α might be a potential target for the treatment of MG exacerbated with inflammation.


Asunto(s)
Inmunidad Humoral , Miastenia Gravis Autoinmune Experimental , Animales , Interleucina-6/farmacología , Subgrupos de Linfocitos T , Células TH1 , Miastenia Gravis Autoinmune Experimental/tratamiento farmacológico , Miastenia Gravis Autoinmune Experimental/patología , Inflamación/tratamiento farmacológico
17.
RSC Adv ; 14(15): 10687-10696, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38567341

RESUMEN

Fe3Al is a good magnetic loss absorber for microwave absorption. However, due to the relatively high density and poor impedance matching ratio, the potential of Fe3Al cannot be fully released. Herein, a dielectric loss absorber of carbon nanotubes (CNTs) is coupled with Fe3Al to form Fe3Al/CNTs composite absorbers. CNTs are randomly tangled and coated on the surface of the Fe3Al flakes, forming a connecting conductive network. By carefully tuning the content of CNTs, the optimized Fe3Al/CNTs composite absorber with 1.5% of CNTs can combine both magnetic loss and dielectric loss mechanisms, thus achieving an impedance matching ratio close to 1 while keeping strong attenuation for enhanced microwave absorption. As a result, an effective absorption bandwidth (RL ≤ -10 dB) of 4.73 GHz at a thickness of 2 mm is achieved.

18.
J Alzheimers Dis ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39031358

RESUMEN

Background: Cerebral autosomal-dominant arteriopathy with subcortical infarction and leukoencephalopathy (CADASIL) is an inherited small-vessel disease that affects the white matter of the brain. Recent studies have confirmed that the deposition of NOTCH3ECD is the main pathological basis of CADASIL; however, whether different mutations present the same pathological characteristics remains to be further studied. Some studies have found that mitochondrial dysfunction is related to CADASIL; however, the specific effects of NOTCH3ECD on mitochondrial remain to be determined. Objective: We aimed to explore the role of mitochondrial dysfunction in CADASIL. Methods: We established transgenic human embryonic kidney-293T cell models (involving alterations in cysteine and non-cysteine residues) via lentiviral transfection. Mitochondrial function and structure were assessed using flow cytometry and transmission electron microscopy, respectively. Mitophagy was assessed using western blotting and immunofluorescence. Results: We demonstrated that NOTCH3ECD deposition affects mitochondrial morphology and function, and that its protein levels are significantly correlated with mitochondrial quality and can directly bind to mitochondria. Moreover, NOTCH3ECD deposition promoted the induction of autophagy and mitophagy. However, these processes were impaired, leading to abnormal mitochondrial accumulation. Conclusions: This study revealed a common pathological feature of NOTCH3ECD deposition caused by different NOTCH3 mutations and provided new insights into the role of NOTCH3ECD in mitochondrial dysfunction and mitophagy.

19.
Elife ; 122024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587455

RESUMEN

The color pattern of insects is one of the most diverse adaptive evolutionary phenotypes. However, the molecular regulation of this color pattern is not fully understood. In this study, we found that the transcription factor Bm-mamo is responsible for black dilute (bd) allele mutations in the silkworm. Bm-mamo belongs to the BTB zinc finger family and is orthologous to mamo in Drosophila melanogaster. This gene has a conserved function in gamete production in Drosophila and silkworms and has evolved a pleiotropic function in the regulation of color patterns in caterpillars. Using RNAi and clustered regularly interspaced short palindromic repeats (CRISPR) technology, we showed that Bm-mamo is a repressor of dark melanin patterns in the larval epidermis. Using in vitro binding assays and gene expression profiling in wild-type and mutant larvae, we also showed that Bm-mamo likely regulates the expression of related pigment synthesis and cuticular protein genes in a coordinated manner to mediate its role in color pattern formation. This mechanism is consistent with the dual role of this transcription factor in regulating both the structure and shape of the cuticle and the pigments that are embedded within it. This study provides new insight into the regulation of color patterns as well as into the construction of more complex epidermal features in some insects.


Asunto(s)
Bombyx , Lepidópteros , Animales , Bombyx/genética , Drosophila melanogaster/genética , Pigmentación/genética , Drosophila , Larva/genética , Factores de Transcripción/genética
20.
Acta Neurol Belg ; 123(1): 153-160, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34410678

RESUMEN

This study evaluated the clinical efficacy of leflunomide combined with low-dose prednisone (0.25 mg/kg/day) for treatment of myasthenia gravis (MG). We enrolled 32 MG patients treated with leflunomide combined with low-dose prednisone. In the control group, 14 patients were treated with low-dose prednisone. Improvement in MG composite (MGC) score of ≥ 3 points from enrollment to 12-week follow-up indicated that the treatment was effective. In the leflunomide combined low-dose prednisone group, the median of MGC score at the time of enrollment was 8.5 points. After 12 weeks, the MGC score dropped to four points. There was statistically significant difference in MGC score before and after treatment (p < 0.001). In the low-dose prednisone group also followed up for 12 weeks, the median of MGC score of the patients decreased from 7 to 4 points, and the change was not statistically significant (p = 0.05). In the leflunomide combined low-dose prednisone group, the improvement of clinical symptoms occurred mainly in the first 4 weeks and the last 4 weeks. Relatively, the decline of the score was mostly seen during the first 8 weeks in the low-dose prednisone group. In leflunomide combined with low-dose prednisone group, the effective rate of generalized MG(gMG) was significantly higher than ocular MG(oMG) (χ2 test, p = 0.036). However, there is no significant difference in the effective rate between AChR-Ab-positive and -negative groups (Fisher's Exact Test, p = 0.625). No serious side effects were observed in any of the subjects. Leflunomide combined with low-dose prednisone rapidly improved the clinical symptoms of patients with MG. It may be a promising treatment for gMG.


Asunto(s)
Miastenia Gravis , Humanos , Prednisona/uso terapéutico , Leflunamida/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Resultado del Tratamiento
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