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1.
J Immunol ; 211(11): 1701-1713, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37843504

RESUMO

Dendritic cells (DCs), a driver of psoriasis pathogenesis, produce IL-23 and trigger IL-23/IL-17 cytokine axis activation. However, the mechanisms regulating IL-23 induction remain unclear. In the current study, we found that mice with E3 ligase FBXW7 deficiency in DCs show reduced skin inflammation correlated with the reduction of IL-23/IL-17 axis cytokines in the imiquimod-induced psoriasis model. Fbxw7 deficiency results in decreased production of IL-23 in DCs. FBXW7 interacts with the lysine N-methyltransferase suppressor of variegation 39 homolog 2 (SUV39H2), which catalyzes the trimethylation of histone H3 Lys9 (H3K9) during transcription regulation. FBXW7 mediates the ubiquitination and degradation of SUV39H2, thus decreasing H3K9m3 deposition on the Il23a promoter. The Suv39h2 knockout mice displayed exacerbated skin inflammation with the IL-23/IL-17 axis overactivating in the psoriasis model. Taken together, our results indicate that FBXW7 increases IL-23 expression in DCs by degrading SUV39H2, thereby aggravating psoriasis-like inflammation. Inhibition of FBXW7 or the FBXW7/SUV39H2/IL-23 axis may represent a novel therapeutic approach to psoriasis.


Assuntos
Dermatite , Psoríase , Animais , Camundongos , Células Dendríticas/metabolismo , Dermatite/patologia , Modelos Animais de Doenças , Epigênese Genética , Proteína 7 com Repetições F-Box-WD/genética , Proteína 7 com Repetições F-Box-WD/metabolismo , Inflamação/metabolismo , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Psoríase/patologia , Pele/patologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
Cancer Sci ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38932450

RESUMO

Atypical L858R or other L858X mutations in the epidermal growth factor receptor (EGFR) gene, beyond the classical EGFRL858R mutation caused by c.2573 T > G, have been identified in non-small cell lung cancer (NSCLC), yet their genomic features and survival benefits with EGFR tyrosine kinase inhibitor (TKI) treatment have not been fully explored. We retrospectively enrolled 489 NSCLC patients with baseline tumor tissue/plasma samples carrying uncommon EGFRL858R (N = 124), EGFRL858Q/M (N = 17), or classical EGFRL858R mutations (N = 348). The comparison of molecular features was performed using treatment-naïve tumor tissues. Survival benefits and resistance mechanisms of first-line EGFR TKI treatment were studied in an advanced disease subcohort. NSCLCs harboring uncommon EGFRL858R had lower TP53 mutation prevalence (p = 0.04) and chromosome instability scores (p = 0.02) than those with classical EGFRL858R. Concomitant EGFRL861Q mutations were enriched in NSCLCs with EGFRL858Q/M (p < 0.01), with cooccurrence in those carrying EGFRL858M. Patients with uncommon EGFRL858R experienced improved progression-free survival (PFS) compared to those with classical EGFRL858R (median: 13.0 vs. 10.0 months, hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.41-0.80). The association remained significant when adjusting for sex, age, histological subtype, TKI category, and anti-vascular therapy (HR: 0.55, 95% CI: 0.39-0.77). Furthermore, EGFRL858Q/M patients showed enhanced first-line PFS (vs. classical EGFRL858R, HR: 0.26, 95% CI: 0.10-0.67), potentially benefiting more from afatinib. Additionally, NSCLCs with uncommon EGFRL858R and classical EGFRL858R had similar resistance profiles to EGFR TKIs. In conclusion, NSCLCs carrying atypical EGFR L858 aberrations, which had fewer TP53 mutations and higher chromosome stability, exhibited improved PFS under first-line EGFR TKIs than those with the classical EGFRL858R.

3.
Small ; : e2400629, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682737

RESUMO

The applications of natural laccases are greatly restricted because of their drawbacks like poor biostability, high costs, and low recovery efficiency. M/NC single atom nanozymes (M/NC SAzymes) are presenting as great substitutes due to their superior enzyme-like activity, excellent selectivity and high stability. In this work, inspired by the catalytic active center of natural enzyme, a biomimetic Fe/NC SAzyme (Fe-SAzyme) with O2-Fe-N4 coordination is successfully developed, exhibiting excellent laccase-like activity. Compared with their natural counterpart, Fe-SAzyme has shown superior catalytic efficiency and excellent stability under a wide range of pH (3.0-9.0), temperature (4-80 °C) and NaCl strength (0-300 mm). Interestingly, density functional theory (DFT) calculations reveal that the high catalytic performance is attributed to the activation of O2 by O2-Fe-N4 sites, which weakened the O─O bonds in the oxygen-to-water oxidation pathway. Furthermore, Fe-SAzyme is successfully applied for efficient aflatoxin B1 removal based on its robust laccase-like catalytic activity. This work provides a strategy for the rational design of laccase-like SAzymes, and the proposed catalytic mechanism will help to understand the coordination environment effect of SAzymes on laccase-like catalytic processes.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38836905

RESUMO

PURPOSE: Acetabular reconstruction in situ after extensive pelvic resection is technically challenging. The aim of this study was to investigate the feasibility of positioning guiders for acetabular reconstruction following pelvic tumor resection and the clinical benefit brought by the approach. METHODS: The study included patients who underwent acetabular reconstruction following periacetabular tumor resection using a modular hemipelvic prosthesis. In the guider-assisted group (n = 14), guiders were designed and applied to assist acetabular reconstruction. In the traditional operation group (n = 18), the patients underwent the same surgery but without the guiders. The displacement of the hip rotation center before and after surgery was calculated. The complications and the Musculoskeletal Tumor Society-93 scores were documented. RESULTS: The overall displacement of the hip rotation center was significantly reduced in the guider-assisted group compared with the traditional operation group (13.83 ± 4.06 vs. 22.95 ± 9.18 mm in P = 0.000, 95%CI 3.90-12.96), especially in the anteroposterior axis (3.77 ± 3.03 versus 13.51 ± 9.43 mm in P = 0.000, 95%CI 3.45-13.09). Guider-assisted acetabular reconstruction reduced the risk of prosthesis dislocation compared with the traditional operation (dislocation risks: 1/14, 7.1% vs. 4/18, 22.2%). CONCLUSION: Positioning guiders can effectively and conveniently help place the modular hemipelvic prosthesis at the native position, which might potentially reduce the risk of prosthesis dislocation. LEVEL OF EVIDENCE: Therapeutic level III.

5.
Cancer Immunol Immunother ; 72(6): 1803-1821, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36680568

RESUMO

Human Vγ9Vδ2 T cells have attracted considerable attention as novel alternative antigen-presenting cells (APCs) with the potential to replace dendritic cells in antitumor immunotherapy owing to their high proliferative capacity and low cost. However, the utility of γδ T cells as APCs to induce CD8+ T cell-mediated antitumor immune response, as well as the mechanism by which they perform APC functions, remains unexplored. In this study, we found that activated Vγ9Vδ2 T cells were capable of inducing robust CD8+ T cell responses in osteosarcoma cells. Activated γδ T cells also effectively suppressed osteosarcoma growth by priming CD8+ T cells in xenograft animal models. Mechanistically, we further revealed that activated γδ T cells exhibited increased HSP90 production, which fed back to upregulate MyD88, followed by JNK activation and a subsequent improvement in CCL5 secretion, leading to enhanced CD8+ T cell cross-priming. Thus, our study suggests that Vγ9Vδ2 T cells represent a promising alternative APC for the development of γδ T cell-based tumor immunotherapy.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Animais , Humanos , Apresentação de Antígeno , Células Apresentadoras de Antígenos , Antígenos , Linfócitos T CD8-Positivos , Ativação Linfocitária , Fator 88 de Diferenciação Mieloide , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , MAP Quinase Quinase 4/metabolismo
6.
Small ; 19(46): e2302886, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37485809

RESUMO

Eutectic Gallium-Indium (EGaIn) liquid metal is an emerging phase change metal material, but its low phase transition enthalpy and low light absorption limit its application in photothermal phase change energy storage materials (PCMs) field. Here, based on the dipole layer mechanism, stearic acid (STA)-EGaIn-based PCMs which exhibit extraordinary solar-thermal performance and phase change enthalpy are fabricated by ball milling method. The wood lamella-inspired cellulose-derived aerogel and molybdenum disulfide (MoS2 ) are used to support the PCMs by the capillary force and decrease the interfacial thermal resistance. The resulted PCMs achieved excellent photothermal conversion performance and leakage proof. They  have excellent thermal conductivity of 0.31 W m-1 K-1 (this is increased by 138% as compared with pure STA), and high phase change enthalpy of187.50 J g-1 , which is higher than the most of the reported PCMs. Additionally, the thermal management system and infrared stealth materials based on the PCMs are developed. This work provides a new way to fabricate smart EGaIn-based PCMs for energy storage device thermal management and infrared stealth.

7.
Small ; 19(35): e2300876, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37127875

RESUMO

The rational design of efficient and cost-effective electrocatalysts for oxygen evolution reaction (OER) with sluggish kinetics, is imperative to diverse clean energy technologies. The performance of electrocatalyst is usually governed by the number of active sites on the surface. Crystalline/amorphous heterostructure has exhibited unique properties and opens new paradigms toward designing electrocatalysts with abundant active sites for improved performance. Hence, Fe doped Ni-Co phosphite (Fe-NiCoHPi) electrocatalyst with cauliflower-like structure, comprising crystalline@amorphous core-shell nanorod, is reported. The experiments uncover that Fe is enriched in the amorphous shell due to the flexibility of the amorphous component. Further density functional theory calculations indicate that the strong electronic interaction between the enriched Fe in the amorphous shell and crystalline core host at the core-shell interface, leads to balanced binding energies of OER intermediates, which is the origin of the catalyst-activity. Eventually, the Fe-NiCoHPi exhibits remarkable activity, with low overpotentials of only 206 and 257 mV at current density of 15 and 100 mA cm-2 . Unceasing durability over 90 h is achieved, which is superior to the effective phosphate electrocatalysts. Although the applications at high current remain challenges , this work provides an approach for designing advanced OER electrocatalysts for sustainable energy devices.

8.
BMC Microbiol ; 23(1): 290, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833633

RESUMO

BACKGROUND: Endophytic bacteria provide nutrients and stimulate systemic resistance during seed germination and plant growth and development, and their functional properties in combating various stresses make them a powerful tool in green agricultural production. In this paper we explored the function of the endophyte community in buckwheat seeds in order to provide a theoretical basis for the application and scientific research of endophytes in buckwheat cultivation. We used pulsed electric field (PEF) technology to treat buckwheat seeds, monitored the effect of high-voltage pulse treatment on buckwheat seed germination, and analyzed the diversity of endophytic bacteria in buckwheat seeds using the amplicon sequencing method. RESULTS: PEF treatment promoted root development during buckwheat seed germination. A total of 350 Operational taxonomic units (OTUs) that were assigned into 103 genera were obtained from control and treatment groups using 16SrRNA amplicon sequencing technology. Additionally, PEF treatment also caused a significant decrease in the abundance of Actinobacteria, Proteobacteria, and Bacteroidetes. The abundance of 28 genera changed significantly as well: 11 genera were more abundant, and 17 were less abundant. The number of associated network edges was reduced from 980 to 117, the number of positive correlations decreased by 89.1%, and the number of negative correlations decreased by 86.6%. CONCLUSION: PEF treatment promoted early root development in buckwheat and was able to alter the seed endophytic bacterial community. This study thus makes a significant contribution to the field of endophyte research and to the application of PEF technology in plant cultivation.


Assuntos
Fagopyrum , Bactérias/genética , Sementes/microbiologia , Raízes de Plantas/microbiologia , Bacteroidetes , Endófitos/genética
9.
BMC Neurol ; 23(1): 189, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173637

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) is a group of autoimmune-mediated disorders of the central nervous system primarily involving the optic nerve and spinal cord. There are limited reports of NMOSD associated with peripheral nerve damage. CASE PRESENTATION: We report a 57-year-old female patient who met the diagnostic criteria for aquaporin 4 (AQP4)-IgG positive NMOSD with undifferentiated connective tissue disease and multiple peripheral neuropathy. In addition, the patient was positive for multiple anti-ganglioside antibodies (anti-GD1a IgG antibodies and anti-GD3 IgM antibodies) and anti-sulfatide IgG antibodies in serum and cerebrospinal fluid. After treatment with methylprednisolone, gamma globulin, plasma exchange, and rituximab, the patient's status improved and was subsequently discharged from our hospital. CONCLUSIONS: The neurologist should be aware of the unusual association between NMOSD and immune-mediated peripheral neuropathy undifferentiated connective tissue disease and nerve damage mediated by multiple antibodies may have combined to cause peripheral nerve damage in this patient.


Assuntos
Doenças Autoimunes , Neuromielite Óptica , Traumatismos dos Nervos Periféricos , Doenças do Tecido Conjuntivo Indiferenciado , Feminino , Humanos , Pessoa de Meia-Idade , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/líquido cefalorraquidiano , Autoanticorpos , Aquaporina 4 , Imunoglobulina G
10.
Inorg Chem ; 62(38): 15711-15718, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37695723

RESUMO

Exploring highly efficient blue-emissive lead-free halide materials is a significant and challenging objective in the study of luminescent materials. This study reports the synthesis of a new zero-dimensional (0D) hybrid zinc halide of [CYP]ZnBr4 (CYP = 1-cyclohexylpiperazine) containing an isolated [ZnBr4]2- tetrahedron. [CYP]ZnBr4 exhibits strong blue light emission with a high photoluminescence quantum yield (PLQY) of 79.22%, surpassing all previously reported 0D zinc halide counterparts. According to the theoretical and experimental studies, the blue light emission is attributed to intrinsic self-trapped excitons resulting from strong electron-phonon coupling and structural deformation. Importantly, [CYP]ZnBr4 demonstrates excellent structural and luminescence stability toward high temperatures (180 °C) over at least half a month. High luminescence efficiency and stability enable [CYP]ZnBr4 to be an efficient blue phosphor to fabricate white light-emitting diodes (LEDs), which produces high-quality white light with a color rendering index (CRI) of 93.1 and a correlated color temperature (CCT) of 5304 K, closely resembling natural sunlight. This white LED also exhibits consistent performance and stability across different drive currents, suggesting the potential for high-power optoelectronic applications. Overall, this study paves the way for the utilization of 0D hybrid halides in advanced solid-state lighting applications.

11.
Angew Chem Int Ed Engl ; 62(10): e202214045, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36646642

RESUMO

The capacity to precisely modulate aptamer affinity is important for a wide variety of applications. However, most such engineering strategies entail laborious trial-and-error testing or require prior knowledge of an aptamer's structure and ligand-binding domain. We describe here a simple and generalizable strategy for allosteric modulation of aptamer affinity by employing a double-stranded molecular clamp that destabilizes aptamer secondary structure through mechanical tension. We demonstrate the effectiveness of the approach with a thrombin-binding aptamer and show that we can alter its affinity by as much as 65-fold. We also show that this modulation can be rendered reversible by introducing a restriction enzyme cleavage site into the molecular clamp domain and describe a design strategy for achieving even more finely-tuned affinity modulation. This strategy requires no prior knowledge of the aptamer's structure and binding mechanism and should thus be generalizable across aptamers.


Assuntos
Aptâmeros de Nucleotídeos , Regulação Alostérica , Aptâmeros de Nucleotídeos/química , Sequência de Bases
12.
Small ; 18(14): e2107636, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35187798

RESUMO

Donning of personal protective equipment (PPE) in the healthcare sector has been intensified by the on-going COVID-19 pandemic around the globe. While extensive PPE provides protection, it typically limits moisture permeability and severely hinders the sweat evaporation process, resulting in greater heat stress on the personnel. Herein, a zinc-poly(vinyl alcohol) (Zn-PVA) composite film is fabricated by embedding a super-hygroscopic zinc-ethanolamine complex (Zn-complex) in the PVA matrix. By attaching the Zn-PVA composite film, the relative humidity (RH) inside the protective suit decreases from 91.0% to 48.2%. The reduced RH level, in turn, enhances evaporative cooling, hence bringing down the heat index from 64.6 to 40.0 °C at an air temperature of 35 °C, remarkably lowering the likelihood of heat stroke. The American Society for Testing and Materials tests conducted on a sweating manikin have also proven that the Zn-PVA composite films can significantly reduce the evaporative resistance of the protective suit by 90%. The low material cost, facile fabrication process, and reusability allow the Zn-PVA composition films to be readily available for healthcare workers worldwide. This application can be further extended to other occupations that are facing severe thermal discomfort and heat stress.


Assuntos
COVID-19 , Sudorese , COVID-19/prevenção & controle , Resposta ao Choque Térmico , Temperatura Alta , Humanos , Pandemias , Suor , Zinco
13.
Cytokine ; 159: 156008, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36063748

RESUMO

IFN-α receptor (IFNAR) is critical for maintaining the crosstalk between cancer cells and lymphocytes. We investigated IFNAR1 expression in peripheral blood CD4+ and CD8+ T cells and explored their relationships with plasma cytokines, chemosensitivity and infiltrated T cells in the tumor microenvironment (TME) of colorectal cancer (CRC). The levels of IFNAR1, IFN-γ, and PD1 in peripheral T cells were tested using flow cytometry. Immunohistochemical staining of IFNAR1 in CRC tissues was performed. A cytometric bead array was used to determine the plasma concentrations of cytokines. In CRC patients, IFNAR1 levels were significantly increased in peripheral blood T cells, and plasma IL-6 levels were also significantly increased. Pearson correlation analysis revealed that IFNAR1 expression in CD8+ T cells was negatively associated with plasma IL-2, IFN-γ, and TNFα. IFNAR1 expression in CD4+ T cells was positively associated with TME infiltrated levels of CD8+ T cells. The levels of CD8+ T cells with IFNAR1 and plasma IFN-γ were associated with chemosensitivity. Collectively, IFNAR1 levels in CD4+ and CD8+ T cells were significantly upregulated in CRC patients and positively associated with T-cell infiltration. IFNAR1 may be a chemotherapy biomarker for predicting response.


Assuntos
Neoplasias Colorretais , Linfócitos do Interstício Tumoral , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Neoplasias Colorretais/metabolismo , Citocinas/metabolismo , Humanos , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Receptor de Interferon alfa e beta/metabolismo , Microambiente Tumoral , Fator de Necrose Tumoral alfa/metabolismo
14.
Heredity (Edinb) ; 128(3): 154-158, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35132207

RESUMO

The dominance effect is considered to be a key factor affecting complex traits. However, previous studies have shown that the improvement of the model, including the dominance effect, is usually less than 1%. This study proposes a novel genomic prediction method called CADM, which combines additive and dominance genetic effects through locus-specific weights on heterozygous genotypes. To the best of our knowledge, this is the first study of weighting dominance effects for genomic prediction. This method was applied to the analysis of chicken (511 birds) and pig (3534 animals) datasets. A 5-fold cross-validation method was used to evaluate the genomic predictive ability. The CADM model was compared with typical models considering additive and dominance genetic effects (ADM) and the model considering only additive genetic effects (AM). Based on the chicken data, using the CADM model, the genomic predictive abilities were improved for all three traits (body weight at 12th week, eviscerating percentage, and breast muscle percentage), and the average improvement in prediction accuracy was 27.1% compared with the AM model, while the ADM model was not better than the AM model. Based on the pig data, the CADM model increased the genomic predictive ability for all the three pig traits (trait names are masked, here designated as T1, T2, and T3), with an average increase of 26.3%, and the ADM model did not improve, or even slightly decreased, compared with the AM model. The results indicate that dominant genetic variation is one of the important sources of phenotypic variation, and the novel prediction model significantly improves the accuracy of genomic prediction.


Assuntos
Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Animais , Genoma , Genômica/métodos , Genótipo , Heterozigoto , Fenótipo , Suínos/genética
15.
Int J Colorectal Dis ; 37(7): 1657-1668, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35716183

RESUMO

PURPOSE: The objective was to compare disease-free survival (DFS) and distant metastasis in patients with neoadjuvant chemoradiotherapy (NCRT) and total neoadjuvant therapy (TNT) for locally advanced rectal cancer. METHODS: Patients with cT3-4N0M0 or cTxN1-2M0 rectal cancer were included in this retrospective study. Patients who received NCRT (radiotherapy with concurrent capecitabine) or TNT (radiotherapy with two concurrent cycles of capecitabine and oxaliplatin (CAPOX) followed by another two cycles of CAPOX) during January 2011 and November 2016 at Beijing Chaoyang Hospital, Capital Medical University were included. All patients had received radical surgery. Adverse events, pathological response and survival outcomes in the two groups were compared. RESULTS: One hundred eighty-two patients were enrolled, 120 in the TNT and 62 in the NCRT groups. No significant between-group differences in neoadjuvant therapy-associated adverse events or surgical complications were found. TNT achieved a higher pathological complete response (pCR) rate (25.8%) compared with NCRT (12.9%, P = 0.044). Patients in the TNT group had a higher 3-year DFS rate (82.8% versus 75.7%, P = 0.041) and lower distant metastasis rate (19.2% versus 33.1%, P = 0.049) than those in the NCRT group. Multivariate analysis showed that NCRT was an independent risk factor for DFS (95%CI 2.023-13.415, P = 0.001) and distant metastasis (95% CI 2.149-20.082, P = 0.001). CONCLUSION: With similar adverse events and a higher pCR rate when compared with NCRT, TNT might be considered as a safe and effective therapeutic strategy to improve prognosis in patients with locally advanced rectal cancer.


Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina/efeitos adversos , Quimiorradioterapia , Quimioterapia de Consolidação , Humanos , Terapia Neoadjuvante/efeitos adversos , Estadiamento de Neoplasias , Segunda Neoplasia Primária/patologia , Oxaliplatina , Neoplasias Retais/tratamento farmacológico , Estudos Retrospectivos
16.
Nucleic Acids Res ; 48(19): 10680-10690, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33021630

RESUMO

Circular DNA aptamers are powerful candidates for therapeutic applications given their dramatically enhanced biostability. Herein we report the first effort to evolve circular DNA aptamers that bind a human protein directly in serum, a complex biofluid. Targeting human thrombin, this strategy has led to the discovery of a circular aptamer, named CTBA4T-B1, that exhibits very high binding affinity (with a dissociation constant of 19 pM), excellent anticoagulation activity (with the half maximal inhibitory concentration of 90 pM) and high stability (with a half-life of 8 h) in human serum, highlighting the advantage of performing aptamer selection directly in the environment where the application is intended. CTBA4T-B1 is predicted to adopt a unique structural fold with a central two-tiered guanine quadruplex capped by two long stem-loops. This structural arrangement differs from all known thrombin binding linear DNA aptamers, demonstrating the added advantage of evolving aptamers from circular DNA libraries. The method described here permits the derivation of circular DNA aptamers directly in biological fluids and could potentially be adapted to generate other types of aptamers for therapeutic applications.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA Circular/química , Trombina/metabolismo , Aptâmeros de Nucleotídeos/sangue , Aptâmeros de Nucleotídeos/metabolismo , DNA Circular/sangue , DNA Circular/metabolismo , Quadruplex G , Humanos , Ligação Proteica , Trombina/química
17.
BMC Genomics ; 22(1): 487, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193033

RESUMO

BACKGROUND: During domestication, remarkable changes in behavior, morphology, physiology and production performance have taken place in farm animals. As one of the most economically important poultry, goose owns a unique appearance characteristic called knob, which is located at the base of the upper bill. However, neither the histomorphology nor the genetic mechanism of the knob phenotype has been revealed in geese. RESULTS: In the present study, integrated radiographic, histological, transcriptomic and genomic analyses revealed the histomorphological characteristics and genetic mechanism of goose knob. The knob skin was developed, and radiographic results demonstrated that the knob bone was obviously protuberant and pneumatized. Histologically, there were major differences in structures in both the knob skin and bone between geese owing knob (namely knob-geese) and those devoid of knob (namely non-knob geese). Through transcriptome analysis, 592 and 952 genes differentially expressed in knob skin and bone, and significantly enriched in PPAR and Calcium pathways in knob skin and bone, respectively, which revealed the molecular mechanisms of histomorphological differences of the knob between knob- and non-knob geese. Furthermore, integrated transcriptomic and genomic analysis contributed to the identification of 17 and 21 candidate genes associated with the knob formation in the skin and bone, respectively. Of them, DIO2 gene could play a pivotal role in determining the knob phenotype in geese. Because a non-synonymous mutation (c.642,923 G > A, P265L) changed DIO2 protein secondary structure in knob geese, and Sanger sequencing further showed that the AA genotype was identified in the population of knob geese, and was prevalent in a crossing population which was artificially selected for 10 generations. CONCLUSIONS: This study was the first to uncover the knob histomorphological characteristics and genetic mechanism in geese, and DIO2 was identified as the crucial gene associated with the knob phenotype. These data not only expand and enrich our knowledge on the molecular mechanisms underlying the formation of head appendages in both mammalian and avian species, but also have important theoretical and practical significance for goose breeding.


Assuntos
Gansos , Transcriptoma , Animais , Testa , Gansos/genética , Perfilação da Expressão Gênica , Genoma
18.
BMC Plant Biol ; 21(1): 426, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34537013

RESUMO

BACKGROUND: Reproduction in most flowering plants may be limited because of the decreased visitation or activity of pollinators in fragmented habitats. Hedysarum scoparium Fisch. et Mey. is an arid region shrub with ecological importance. We explored the pollen limitation and seed set of Hedysarum scoparium in fragmented and restored environments, and examined whether pollen limitation is a significant limiting factor for seed set. We also compared floral traits and pollinator visitation between both habitats, and we determined the difference of floral traits and pollinators influenced reproductive success in Hedysarum scoparium. RESULTS: Our results indicated that supplementation with pollen significantly increased seed set per flower, which is pollen-limited in this species. Furthermore, there was greater seed set of the hand cross-pollination group in the restored habitat compared to the fragmented environment. More visits by Apis mellifera were recorded in the restored habitats, which may explain the difference in seed production between the fragmented and restored habitats. CONCLUSIONS: In this study, a positive association between pollinator visitation frequency and open flower number was observed. The findings of this study are important for experimentally quantifying the effects of floral traits and pollinators on plant reproductive success in different habitats.


Assuntos
Fabaceae/fisiologia , Flores/fisiologia , Pólen/fisiologia , Animais , China , Ecossistema , Polinização , Sementes/crescimento & desenvolvimento
19.
J Nanobiotechnology ; 19(1): 207, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34247649

RESUMO

Metal ions have been identified as important bone metabolism regulators and widely used in the field of bone tissue engineering, however their exact role during bone regeneration remains unclear. Herein, the aim of study was to comprehensively explore the interactions between osteoinductive and osteo-immunomodulatory properties of these metal ions. In particular, the osteoinductive role of zinc ions (Zn2+), as well as its interactions with local immune microenvironment during bone healing process, was investigated in this study using a sustained Zn2+ delivery system incorporating Zn2+ into ß-tricalcium phosphate/poly(L-lactic acid) (TCP/PLLA) scaffolds. The presence of Zn2+ largely enhanced osteogenic differentiation of periosteum-derived progenitor cells (PDPCs), which was coincident with increased transition from M1 to M2 macrophages (M[Formula: see text]s). We further confirmed that induction of M2 polarization by Zn2+ was realized via PI3K/Akt/mTOR pathway, whereas marker molecules on this pathway were strictly regulated by the addition of Zn2+. Synergically, this favorable immunomodulatory effect of Zn2+ further improved the osteogenic differentiation of PDPCs induced by Zn2+ in vitro. Consistently, the spontaneous osteogenesis and pro-healing osteoimmunomodulation of the scaffolds were thoroughly identified in vivo using a rat air pouch model and a calvarial critical-size defect model. Taken together, Zn2+-releasing bioactive ceramics could be ideal scaffolds in bone tissue engineering due to their reciprocal interactions between osteoinductive and immunomodulatory characteristics. Clarification of this synergic role of Zn2+ during osteogenesis could pave the way to develop more sophisticated metal-ion based orthopedic therapeutic strategies.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Zinco/química , Zinco/farmacologia , Animais , Osso e Ossos/patologia , Fosfatos de Cálcio , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cerâmica , Liberação Controlada de Fármacos , Feminino , Masculino , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Poliésteres , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Células-Tronco , Engenharia Tecidual , Alicerces Teciduais
20.
Hereditas ; 158(1): 26, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271985

RESUMO

BACKGROUND: miRNAs are a type of conserved, small RNA molecule that regulate gene expression and play an important role in the growth and development of plants. miRNAs are involved in seed germination, root development, shoot apical meristem maintenance, leaf development, and flower development by regulating various target genes. However, the role of miRNAs in the mechanism of tea plant flower sterility remains unclear. Therefore, we performed miRNA sequencing on the flowers of fertile male parents, female parents, and sterile offspring. RESULTS: A total of 55 known miRNAs and 90 unknown miRNAs were identified. In the infertile progeny, 37 miRNAs were differentially expressed; 18 were up-regulated and 19 were down-regulated. miR156, miR157, miR164, miR167, miR169, miR2111 and miR396 family members were down-regulated, and miR160, miR172 and miR319 family members were up-regulated. Moreover, we predicted that the 37 differentially expressed miRNAs target a total of 363 genes, which were enriched in 31 biological functions. We predicted that miR156 targets 142 genes, including ATD1A, SPL, ACA1, ACA2, CKB22 and MADS2. CONCLUSION: We detected a large number of differentially expressed miRNAs in the sterile tea plant flowers, and their target genes were involved in complex biological processes. Among these miRNAs, the down-regulation of miR156 may be one of the factor in the formation of sterile floral buds in tea plants.


Assuntos
Camellia sinensis/genética , MicroRNAs/genética , Infertilidade das Plantas/genética , Flores/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , RNA de Plantas/genética , Análise de Sequência de RNA
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