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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38627939

RESUMO

The latest breakthroughs in spatially resolved transcriptomics technology offer comprehensive opportunities to delve into gene expression patterns within the tissue microenvironment. However, the precise identification of spatial domains within tissues remains challenging. In this study, we introduce AttentionVGAE (AVGN), which integrates slice images, spatial information and raw gene expression while calibrating low-quality gene expression. By combining the variational graph autoencoder with multi-head attention blocks (MHA blocks), AVGN captures spatial relationships in tissue gene expression, adaptively focusing on key features and alleviating the need for prior knowledge of cluster numbers, thereby achieving superior clustering performance. Particularly, AVGN attempts to balance the model's attention focus on local and global structures by utilizing MHA blocks, an aspect that current graph neural networks have not extensively addressed. Benchmark testing demonstrates its significant efficacy in elucidating tissue anatomy and interpreting tumor heterogeneity, indicating its potential in advancing spatial transcriptomics research and understanding complex biological phenomena.


Assuntos
Benchmarking , Perfilação da Expressão Gênica , Análise por Conglomerados , Redes Neurais de Computação
2.
Eur J Med Res ; 29(1): 151, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429762

RESUMO

BACKGROUND: Urosepsis is a life-threatening organ disease in which pathogenic microorganisms in the urine enter the blood through the vessels, causing an imbalance in the immune response to infection. The aim of this study was to elucidate the role of testicular orphan receptor 4 (TR4) in urosepsis. METHODS: The role of TR4 in the progression and prognosis of urosepsis was confirmed by analyzing data from online databases and clinical human samples. To mimic urosepsis, we injected E. coli bacteria into the renal pelvis of mice to create a urosepsis model. Hematoxylin and eosin staining was used to observe histopathological changes in urosepsis. The effects of the upregulation or downregulation of TR4 on macrophage pyroptosis were verified in vitro. Chromatin immunoprecipitation assay was used to verify the effect of TR4 on Gasdermin D (GSDMD) transcription. RESULTS: TR4 was more highly expressed in the nonsurviving group than in the surviving group. Furthermore, overexpressing TR4 promoted inflammatory cytokine expression, and knocking down TR4 attenuated inflammatory cytokine expression. Mechanistically, TR4 promoted pyroptosis by regulating the expression of GSDMD in urosepsis. Furthermore, we also found that TR4 knockdown protected mice from urosepsis induced by the E. coli. CONCLUSIONS: TR4 functions as a key regulator of urosepsis by mediating pyroptosis, which regulates GSDMD expression. Targeting TR4 may be a potential strategy for urosepsis treatment.


Assuntos
Líquidos Corporais , Sepse , Animais , Humanos , Camundongos , Citocinas , Amarelo de Eosina-(YS) , Escherichia coli , Gasderminas , Proteínas de Ligação a Fosfato/genética , Sepse/complicações , Sepse/genética
3.
J Imaging Inform Med ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326533

RESUMO

In intraoperative brain cancer procedures, real-time diagnosis is essential for ensuring safe and effective care. The prevailing workflow, which relies on histological staining with hematoxylin and eosin (H&E) for tissue processing, is resource-intensive, time-consuming, and requires considerable labor. Recently, an innovative approach combining stimulated Raman histology (SRH) and deep convolutional neural networks (CNN) has emerged, creating a new avenue for real-time cancer diagnosis during surgery. While this approach exhibits potential, there exists an opportunity for refinement in the domain of feature extraction. In this study, we employ coherent Raman scattering imaging method and a self-supervised deep learning model (VQVAE2) to enhance the speed of SRH image acquisition and feature representation, thereby enhancing the capability of automated real-time bedside diagnosis. Specifically, we propose the VQSRS network, which integrates vector quantization with a proxy task based on patch annotation for analysis of brain tumor subtypes. Training on images collected from the SRS microscopy system, our VQSRS demonstrates a significant speed enhancement over traditional techniques (e.g., 20-30 min). Comparative studies in dimensionality reduction clustering confirm the diagnostic capacity of VQSRS rivals that of CNN. By learning a hierarchical structure of recognizable histological features, VQSRS classifies major tissue pathological categories in brain tumors. Additionally, an external semantic segmentation method is applied for identifying tumor-infiltrated regions in SRH images. Collectively, these findings indicate that this automated real-time prediction technique holds the potential to streamline intraoperative cancer diagnosis, providing assistance to pathologists in simplifying the process.

4.
Gland Surg ; 13(1): 45-58, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38323233

RESUMO

Background: Adipose-derived stem cells (ADSCs) are closely associated with the survival rate of transplanted fat in breast reconstruction after breast cancer surgery. Nevertheless, the intrinsic mechanisms regulating ADSCs adipogenic differentiation remain ambiguous. The aim of our study was to explore the relevant genes and pathways to elucidate the potential mechanisms of adipogenic differentiation in ADSCs. Methods: The Gene Expression Omnibus (GEO) dataset GSE61302 was downloaded and analyzed to identify differentially expressed genes (DEGs). Key genes and signaling pathways were obtained through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional and enrichment analysis. Protein-protein interaction (PPI) network and hub gene analyses were performed with the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database and Cytoscape software. Finally, the transcription levels of hub genes in the adipogenic differentiated group and undifferentiated group of ADSCs were compared via real-time quantitative polymerase chain reaction (RT-qPCR). Results: In total, 1,091 DEGs were identified through bioinformatics analysis of the adipogenic differentiated group and undifferentiated group. If was then found that the 10 downregulated key genes, CCNB1, NUSAP1, DLGAP5, TTK, CCNB2, KIF23, BUB1B, CDC20, CDCA8, and KIF11 may play important roles in the adipogenic differentiation of ADSCs. Subsequent in vitro experimental verification also revealed that the messenger RNA (mRNA) expression levels of cyclin B1 in adipogenic differentiated cells and undifferentiated cells were significantly different at the early stage (P<0.05), but there was no significant difference at the late stage (P>0.05). Conclusions: As a key gene, CCNB1 might be a potential biomarker in the adipogenic differentiation of ADSCs at the early stage.

5.
Acta Otolaryngol ; 144(1): 65-70, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38265886

RESUMO

BACKGROUND: There is a lack of effective treatment for idiopathic unilateral vocal fold paralysis (IUVFP). A better phonation was reported by patients after laryngeal nerve stimulation during our clinical examination. OBJECTIVES: This study aims to investigate immediate effect of recurrent laryngeal nerve (RLN) stimulation on phonation in patients with IUVFP. MATERIAL AND METHODS: Sixty-two patients with clinically identified IUVFP underwent RLN stimulation with needle electrodes. Laryngoscopy, acoustic analysis, and voice perception assessment were performed for quantitative comparison of vocal function and voice quality before and after the intervention. RESULTS: Laryngoscopic images showed a larger motion range of the paralyzed vocal fold (p < .01) and better glottal closure (p < .01) after RLN stimulation. Acoustic analysis revealed that the dysphonia severity index increased significantly (p < .01) while the jitter and shimmer decreased after the intervention (p < .05). According to perceptual evaluation, RLN stimulation significantly increased RBH grades in patients with IUVFP (p < .01). Furthermore, the improvement in voice perception had a moderate positive correlation with the decrease in the glottal closure. CONCLUSIONS AND SIGNIFICANCE: This study shows a short-term improvement of phonation in IUVFP patients after RLN stimulation, which provides proof-of-concept for trialing a controlled delivery of RLN stimulation and assessing durability of any observed responses.


Assuntos
Paralisia das Pregas Vocais , Voz , Humanos , Nervo Laríngeo Recorrente , Prega Vocal , Paralisia das Pregas Vocais/terapia , Voz/fisiologia , Fonação/fisiologia
6.
Talanta ; 269: 125457, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039678

RESUMO

Escherichia coli O157: H7 (E. coli O157: H7) is one of the most common foodborne pathogens and is widespread in food and the environment. Thus, it is significant for rapidly detecting E. coli O157: H7. In this study, a colorimetric aptasensor based on aptamer-functionalized magnetic beads, exonuclease III (Exo III), and G-triplex/hemin was proposed for the detection of E. coli O157: H7. The functional hairpin HP was designed in the system, which includes two parts of a stem containing the G-triplex sequence and a tail complementary to cDNA. E. coli O157: H7 competed to bind the aptamer (Apt) in the Apt-cDNA complex to obtain cDNA. The cDNA then bound to the tail of HP to trigger Exo III digestion and release the single-stranded DNA containing the G-triplex sequence. G-triplex/hemin DNAzyme could catalyze TMB to produce visible color changes and detectable absorbance signals in the presence of H2O2. Based on the optimal conditions, E. coli O157: H7 could be detected down to 1.3 × 103 CFU/mL, with a wide linear range from 1.3 × 103 to 1.3 × 107 CFU/mL. This method had a distinguished ability to non-target bacteria, which showed good specificity. In addition, the system was successfully applied to detect E. coli O157: H7 in milk samples.


Assuntos
Aptâmeros de Nucleotídeos , DNA Catalítico , Escherichia coli O157 , Escherichia coli O157/genética , Hemina , Colorimetria/métodos , DNA Complementar , Peróxido de Hidrogênio , Aptâmeros de Nucleotídeos/genética , Fenômenos Magnéticos , Microbiologia de Alimentos
7.
BMC Cancer ; 23(1): 1114, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968576

RESUMO

BACKGROUND: The establishment of sister chromatid cohesion N-acetyltransferase 2 (ESCO2) is involved in the development of multiple malignancies. However, its role in hypopharyngeal carcinoma (HPC) progression remains uncharacterized. METHODS: This study employed bioinformatics to determine the ESCO2 expression in head and neck squamous cell carcinoma (HNSC) and normal tissues. In vitro cell proliferation, migration, apoptosis, and/or cell cycle distribution assays were used to determine the function of ESCO2 and its relationship with STAT1. Xenograft models were established in nude mice to determine ESCO2 in HPC growth in vivo. Co-immunoprecipitation/mass spectrometry (Co-IP/MS) was conducted to identify the potential ESCO2 binding partners. RESULTS: We found that ESCO2 expression was elevated in HNSC tissues, and ESCO2 depletion suppressed tumor cell migration in vitro and inhibited tumor growth in vitro and in vivo. Co-IP/MS and immunoblotting assays revealed the interaction between ESCO2 and STAT1 in HPC cells. STAT1-overexpression compromised ESCO2-mediated suppressive effects on HPC cell proliferation, viability, and migration. CONCLUSIONS: These findings suggest that ESCO2 is crucial in promoting HPC malignant progression through the STAT1 pathway and provides novel therapeutic targets for HPC treatment.


Assuntos
Segregação de Cromossomos , Neoplasias de Cabeça e Pescoço , Animais , Camundongos , Humanos , Camundongos Nus , Proliferação de Células , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Linhagem Celular Tumoral , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Acetiltransferases/genética , Proteínas Cromossômicas não Histona/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-37944970

RESUMO

Objective: This study aims to provide clinical evidence for the treatment of idiopathic scoliosis (IS) by assessing the therapeutic effectiveness of combining functional rehabilitation training with orthosis. Methods: We enrolled a total of 94 IS patients who were admitted to our hospital from April 2020 to February 2022. These patients were randomly assigned into two groups: a research group (RG; n=47) receiving functional rehabilitation training combined with orthosis and a control group (CG; n=47) receiving orthosis treatment alone. Clinical outcomes were evaluated one year after treatment. We also measured the Cobb angle, apical vertebral rotation (AVR), and the distance between the vertical line of the sacrum and the spinous process of the scoliosis parietal vertebra before and after treatment to determine apical vertebral translation (AVT) from the sacral midline and lumbar range of motion (ROM). Patient quality of life was assessed using the Short-Form 36 Item Health Survey (SF-36). Results: After treatment, the research group exhibited significantly lower Cobb angles, AVR, and AVT, along with a higher overall response rate and greater lumbar ROM compared to the control group (P < .05). Post-treatment SF-36 scores increased in both groups, with notably higher scores in the research group (P < .05). Conclusions: Combining functional rehabilitation training with orthosis is an effective approach for the treatment of IS and holds substantial clinical significance.

9.
Analyst ; 148(20): 5124-5132, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37681669

RESUMO

Targeted imaging is playing an increasingly important role in the early detection and precise diagnosis of cancer. This need has motivated research into sensory nanomaterials that can be constructed into imaging agents to serve as biosensors. Graphene quantum dots (GQDs) as a valuable nanoprobe show great potential for use in two-photon biological imaging. However, most as-prepared GQDs exhibit a low two-photon absorption cross-section, narrow spectral coverage, and "one-to-one" signal conversion mode, which greatly hamper their wide application in sensitive early-stage cancer detection. Herein, a versatile strategy has been employed to fabricate an aptamer Sgc8c-functionalized hybrid as a proof-of-concept of the signal amplification strategy for targeted cancer imaging. In this study, GQDs with two-photon imaging performance, and silica nanoparticles (SiO2 NPs) as nanocarriers to provide amplified recognition events by high loading of GQD signal tags, were adopted to construct a two-photon hybrid-based signal amplification strategy. Thus, the obtained hybrid (denoted SiO2@GQDs) enabled extremely strong fluorescence with a quantum yield up to 0.49, excellent photostability and biocompatibility, and enhanced bright two-photon fluorescence up to 2.7 times that of bare GQDs (excitation at 760 nm; emission at 512 nm). Moreover, further modification with aptamer Sgc8c showed little disruption to the structure of the SiO2@GQDs-hybrid and the corresponding two-photon emission. Hence, SiO2@GQDs-Sgc8c showed specific responses to target cells. Moreover, it could be used as a signal-amplifying two-photon nanoprobe for targeted cancer imaging with high specificity and great efficiency, which exhibits a distinct green fluorescence compared to that of GQDs-Sgc8c or SiO2@GQDs. This signal amplification strategy holds great potential for the accurate early diagnosis of tumors and offers new tools for the detection a wide variety of analytes in clinical application.


Assuntos
Grafite , Nanopartículas , Neoplasias , Pontos Quânticos , Humanos , Pontos Quânticos/química , Grafite/química , Dióxido de Silício/química , Nanopartículas/química , Oligonucleotídeos , Neoplasias/diagnóstico por imagem
10.
Dalton Trans ; 52(21): 7175-7181, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37162257

RESUMO

A 2,2'-bipyridyl calcium complex based on a tridentate ligand [CH3C(N-2,6-iPr2C6H3)CHC(CH3)NCH2CH2N(CH3)2]Ca(bipy)(THF) (1) was prepared by the reduction of {[CH3C(N-2,6-iPr2C6H3)CHC(CH3)NCH2CH2N(CH3)2]CaI(THF)}2 with potassium graphite in the presence of 2,2'-bipyridine (bipy). Complex 1 is a good Ca(I)synthon, as shown by its reactivity with I2, PhCH2SSCH2Ph, PhCH2SeSeCH2Ph and 9-fluorenone, yielding the calcium iodide complex [CH3C(N-2,6-iPr2C6H3)CHC(CH3)NCH2CH2N(CH3)2]CaI(bipy) (2), calcium thiolate [CH3C(N-2,6-iPr2C6H3)CHC(CH3)NCH2CH2N(CH3)2]Ca(SCH2Ph)(bipy) (3), calcium selenolate [CH3C(N-2,6-iPr2C6H3)CHC(CH3)NCH2CH2N(CH3)2]Ca(SeCH2Ph)(bipy) (4), and calcium ketyl complex [CH3C(N-2,6-iPr2C6H3)CHC(CH3)NCH2CH2N(CH3)2]Ca[O-(9-C13H8˙)](bipy)·2THF (5·2THF), respectively. In addition, reactions of complex 5 with CS2, CH2CHCH2Br and PhCH2Br give the corresponding dimeric bis(thiolate) complex {[S2CC(CMe(NAr))C(Me)NCH2CH2NMe2]Ca(DME)}2 (6), dimeric calcium bromide complex {[(9-CH2CHCH2-C13H8-9)-O]CaBr(THF)(bipy)}2 (7) and {[(9-C6H5CH2-C13H8-9)-O]CaBr[O-(9-C13H8)](bipy)}2 (8). These results demonstrated that the calcium ketyl complex 5 can also be employed as a single-electron transfer reagent. All the new compounds were characterized by various spectroscopic methods, and their solid-state structures were further confirmed by single-crystal X-ray diffraction analyses.

11.
Front Bioeng Biotechnol ; 11: 1196174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229496

RESUMO

The rapid progress of interdisciplinary researches from materials science, biotechnologies, biomedical engineering, and medicine, have resulted in the emerging of bioinspired skins for various fantasticating applications. Bioinspired skin is highly promising in the application of rehabilitation medicine owing to their advantages, including personalization, excellent biocompatibility, multi-functionality, easy maintainability and wearability, and mass production. Therefore, this review presents the recent progress of bioinspired skin towards next-generation rehabilitation medicine. The classification is first briefly introduced. Then, various applications of bioinspired skins in the field of rehabilitation medicine at home and abroad are discussed in detail. Last, we provide the challenges we are facing now, and propose the next research directions.

12.
Exp Appl Acarol ; 89(3-4): 345-362, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37027055

RESUMO

Transformer-2 (tra-2) is an important sex-determining gene in insects. It also plays a role in the reproduction of phytoseiid mites. We performed bioinformatic analyses for the tra-2 ortholog in Phytoseiulus persimilis (termed Pptra-2), measured its expression at different stages and quantitatively identified its function in reproduction. This gene encodes 288 amino acids with a conserved RRM domain. The peak of its expression was observed in adult females, especially ca. 5 days after mating. In addition, expression is also higher in eggs than in other stages and adult males. When Pptra-2 was silenced through RNA interference with oral delivery of dsRNA, 56% of the females had their egg hatching rates decreased in the first 5 days, from ca. 100% to ca. 20%, and maintained at low levels during the rest of the oviposition period. To detect other genes functionally related to Pptra-2, transcriptome analyses were performed on day 5 after mating. We compared mRNA expressions among interfered females with significantly reduced egg hatching rate, interfered females without significant hatching rate and CK. In total 403 differential genes were identified, of which 42 functional genes involved in the regulation of female reproduction and embryonic development were screened and discussed.


Assuntos
Ácaros , Reprodução , Masculino , Feminino , Animais , Ácaros/fisiologia , Oviposição , Interferência de RNA , Desenvolvimento Embrionário
13.
Vet Med Sci ; 9(1): 523-534, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36583994

RESUMO

BACKGROUND: Brucellosis, caused by Brucella spp., is a major zoonotic public health threat. Although several Brucella vaccines have been demonstrated for use in animals, Brucella spp. can cause human infection and to date, there are no human-use vaccines licensed by any agency. Recently, methods in vaccine informatics have made major breakthroughs in peptide-based epitopes, opening up a new avenue of vaccine development. OBJECTIVES: The purpose of this article was to identify potential antigenic peptides in Brucella by proteome and peptidome analyses. METHODS: Mouse infection models were first established by injection with Brucella and spleen protein profiles were then analysed. Subsequently, the major histocompatibility complex class I or II (major histocompatibility complex [MHC]-I/II)-binding peptides in blood samples were collected by immunoprecipitation and peptides derived from Brucella proteins were identified through liquid chromatography-mass spectrometry (LC-MS/MS). These peptides were then evaluated in a variety of ways, such as in terms of conservation in Brucella and synchronicity in predicted peptides (similarity and coverage), which allowed us to more effectively measure their antigenic potential. RESULTS: The expression of the inflammatory cytokines IL1B and IFN-γ was significantly altered in the spleen of infected mice and some Brucella proteins, such as Muri, AcpP and GroES, were also detected. Meanwhile, in blood, 35 peptides were identified and most showed high conservation, highlighting their potential as antigen epitopes for vaccine development. In particular, we identified four proteins containing both MHC-I- and MHC-II-binding peptides including AtpA, AtpD, DnaK and BAbS19_II02030. They were also compared with the predicted peptides to estimate their reliability. CONCLUSIONS: The peptides we screened could bind to MHC molecules. After being stimulated with antigen T epitopes, Memory T cells can stimulate T cell activation and promote immune responses. Our results indicated that the peptides we identified may be good candidate targets for the design of subunit vaccines and these results pave the way for the study of safer vaccines against Brucella.


Assuntos
Brucella , Animais , Camundongos , Proteoma , Cromatografia Líquida/veterinária , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/veterinária , Epitopos , Peptídeos
14.
Artigo em Inglês | MEDLINE | ID: mdl-35836834

RESUMO

Objectives: This study was designed to explore the relationship between Helicobacter pylori (Hp) infection and reflux laryngopharyngitis (RLP) and to evaluate the outcome of anti-Hp therapy in improving RLP symptoms. Methods: A total of 410 patients with RLP were enrolled and tested for Hp infection. The association of Hp infection with reflux symptom index (RSI) and reflux finding score (RFS) was determined. Hp-positive patients received either a proton pump inhibitor (PPI) omeprazole alone (control group) or a combination regimen (experimental group) consisting of omeprazole, mosapride citrate, amoxicillin, and clarithromycin. Therapeutic outcomes were compared 4 weeks later. Results: Of the 410 participants, 290 were Hp-positive and 120 Hp-negative. Both RSI and RFS were significantly higher in Hp-positive patients than in Hp-negative patients. Hp infection status was positively correlated with RSI (P < 0.05) and RFS (P < 0.05). The overall response rate was higher in the experimental group than in the control group. Both the groups had a significant reduction in RSI and RFS after therapy, with a greater improvement in the experimental group (P < 0.05). Conclusion: Our findings establish a link between Hp infection and RLP. Anti-Hp therapy improves RSI and RFS in RLP patients. Therefore, Hp eradication drugs may be added to the PPI-based regimen in the treatment of RLP.

15.
Comput Intell Neurosci ; 2022: 9987313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707198

RESUMO

Motor function rehabilitation training is to restore the motor function of hand injury to the maximum extent and meet the needs of patients' daily behavior. At present, motor function evaluation and rehabilitation training work have disadvantages such as relying on the subjective experience of physicians, unable to quantitatively assess the loss of motor function, and single rehabilitation training method. Most of these methods only focus on the independent motion range of a single organ, lack of consideration of the constraint relationship between adjacent fingers, and do not build a visual model for it. To end this issue, for the purpose of sports rehabilitation, combined with the status and application of rehabilitation machines, this paper proposed a cycling rehabilitation training system based on physiological signal extraction of ensemble empirical mode decomposition (EEMD) algorithm. Results compared with the previous rehabilitation training, the muscle tension level of patients' upper limbs decreased, and the strength of some muscles also increased. With the progress of rehabilitation training, the contralateral dominance coefficient showed an upward trend, which further confirmed the role of the proposed method in sports rehabilitation, and also provided a new idea for the evaluation of rehabilitation training effect of patients in the future.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Algoritmos , Dedos , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior
16.
Plant Biotechnol J ; 20(8): 1487-1501, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35426230

RESUMO

Riboflavin is the precursor of essential cofactors for diverse metabolic processes. Unlike animals, plants can de novo produce riboflavin through an ancestrally conserved pathway, like bacteria and fungi. However, the mechanism by which riboflavin regulates seed development is poorly understood. Here, we report a novel maize (Zea mays L.) opaque mutant o18, which displays an increase in lysine accumulation, but impaired endosperm filling and embryo development. O18 encodes a rate-limiting bifunctional enzyme ZmRIBA1, targeted to plastid where to initiate riboflavin biosynthesis. Loss of function of O18 specifically disrupts respiratory complexes I and II, but also decreases SDH1 flavinylation, and in turn shifts the mitochondrial tricarboxylic acid (TCA) cycle to glycolysis. The deprivation of cellular energy leads to cell-cycle arrest at G1 and S phases in both mitosis and endoreduplication during endosperm development. The unexpected up-regulation of cell-cycle genes in o18 correlates with the increase of H3K4me3 levels, revealing a possible H3K4me-mediated epigenetic back-up mechanism for cell-cycle progression under unfavourable circumstances. Overexpression of O18 increases riboflavin production and confers osmotic tolerance. Altogether, our results substantiate a key role of riboflavin in coordinating cellular energy and cell cycle to modulate maize endosperm development.


Assuntos
Endosperma , Zea mays , Ciclo Celular/genética , Endosperma/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Riboflavina/genética , Riboflavina/metabolismo , Sementes , Zea mays/metabolismo
17.
Zhen Ci Yan Jiu ; 47(1): 33-8, 2022 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-35128868

RESUMO

OBJECTIVE: To observe the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on the motor function and the expression of glial fibrillary acidic protein (GFAP) and microtubule associated protein 2 (MAP2) in cerebral ischemic penumbra of rats with middle cerebral artery occlusion (MCAO) and explore the mechanism of taVNS in the improvement of motor function in MCAO rats. METHODS: A total of 48 male SD rats were randomized into a sham-operation group, a model group, a transcutaneous auricular non-vagus nerve stimulation (tnVNS) group and a taVNS group, with 12 rats in each group. The suture-occluded method was adopted to prepare MCAO rat model. The auricular rim was stimulated in the tnVNS group and the concha stimulated in the taVNS group, 2 mA in intensity, 10 Hz in frequency, 30 min each time, once a day, for 14 days consecutively. The nerve functional assessment was recorded in each group. The expressions of nicotinic acetylcholine receptor (α7nAchR) in the cerebral ischemic penumbra and the spleen were detected by using Western blot. With the immunofluorescence, the expressions of GFAP and MAP2 were detected. RESULTS: After modeling, compared with the sham-operation group, the nerve functional score was increased in the model group, the tnVNS group and the taVNS group (P<0.01), suggesting the success of modeling. After treatment, the score was increased in the model group (P<0.01) as compared with the sham-operation group. Compared with the model group, the neurological deficit score was reduced in the taVNS group (P<0.01). Compared with the sham-operation group, GFAP expression was increased and MAP2 expression was reduced remarkably in the cerebral ischemic penumbra in the model group (P<0.05). In comparison with the model group, GFAP expression was reduced, while MAP2 expression was increased remarkably in the cerebral ischemic penumbra in the taVNS group (P<0.05). There were no significant differences in the abovementioned indexes between the model group and tnVNS group (P>0.05). The differences in the expression of α7nAchR in the cerebral ischemic penumbra and the spleen had no statistical significance among groups (P>0.05). CONCLUSION: TaVNS is effective on neuroprotection in MCAO rats, which may be related to its function of inhibition of GFAP expression and promotion of MAP2 expression in the ischemic penumbra.


Assuntos
Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Animais , Proteína Glial Fibrilar Ácida/genética , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/terapia , Masculino , Proteínas Associadas aos Microtúbulos , Artéria Cerebral Média , Ratos , Ratos Sprague-Dawley
18.
Nanomaterials (Basel) ; 12(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35159906

RESUMO

Formic acid is an appealing hydrogen storage material. In order to rapidly produce hydrogen from formic acid under relatively mild conditions, high-efficiency and stable photocatalytic systems are of great significance to prompt hydrogen (H2) evolution from formic acid. In this paper, an efficient and stable photocatalytic system (CdS/P/MoS2) for H2 production from formic acid is successfully constructed by elemental P doping of CdS nanorods combining with in situ photodeposition of MoS2. In this system, P doping reduces the band gap of CdS for enhanced light absorption, as well as promoting the separation of photogenerated charge carriers. More importantly, MoS2 nanoparticles decorated on P-doped CdS nanorods can play as noble-metal-free cocatalysts, which increase the light adsorption, facilitate the charge transfer and effectively accelerate the hydrogen evolution reaction. Consequently, the apparent quantum efficiency (AQE) of the designed CdS/P/MoS2 is up to 6.39% at 420 nm, while the H2 evolution rate is boosted to 68.89 mmol·g-1·h-1, which is 10 times higher than that of pristine CdS. This study could provide an alternative strategy for the development of competitive CdS-based photocatalysts as well as noble-metal-free photocatalytic systems toward efficient hydrogen production.

19.
Neural Regen Res ; 17(3): 594-600, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34380899

RESUMO

Previous studies have shown that vagus nerve stimulation can improve patients' locomotor function. The stimulation of the auricular vagus nerve, which is the only superficial branch of the vagus nerve, may have similar effects to vagus nerve stimulation. However, the precise mechanisms remain poorly understood. In this study, rat models of cerebral ischemia/reperfusion injury were established by modified Longa ligation. Twenty-four hours later, 7-day auricular vagus nerve stimulation was performed. The results showed that auricular vagus nerve stimulation promoted the secretion of acetylcholine, inhibited the secretion of interleukin-1ß, interleukin-6, and tumor necrosis factor-α, and reduced connexin 43 phosphorylation in the ischemic penumbra and motor cortex, promoting locomotor function recovery in rats with cerebral ischemia/reperfusion injury. These findings suggested that auricular vagus nerve stimulation promotes the recovery of locomotor function in rats with cerebral ischemia/reperfusion injury by altering the secretion of acetylcholine and inflammatory factors and the phosphorylation of connexin 43. This study was approved by the Animal Use and Management Committee of Shanghai University of Traditional Chinese Medicine on November 8, 2019 (approval No. PZSHUTCM191108014).

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