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1.
Metabolism ; : 156042, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39362520

RESUMO

BACKGROUND: Fam3a has been demonstrated to regulate pancreatic ß-cell function and glucose homeostasis. However, the role and mechanism of Fam3a in regulating α-cell function remains unexplored. METHODS: Glucagon and glucagon-like peptide-1 (GLP-1) levels in pancreas and plasma were measured in global Fam3a knockout (Fam3a-/-) mice. Human islet single-cell RNA sequencing (scRNA-seq) datasets were utilized to analyze gene expression correlations between FAM3A and PCSK1 (encoding PC1/3, which processes proglucagon into GLP-1). Mouse pancreatic α-cell line αTC1.9 cells were transfected with Fam3a siRNA or plasmid for Fam3a knockdown or overexpression to explore the effects of Fam3a on PC1/3 expression and GLP-1 production. The downstream mediator (including Nr4a2) was identified by transcriptomic analysis, and its role was confirmed by Fam3a knockdown or overexpression in αTC1.9 cells. Based on the interacted protein of Nr4a2 and the direct binding to Pcsk1 promoter, the transcription factor Foxa2 was selected for further verification. Nuclear translocation assay and dual-luciferase reporter assay were used to clarify the involvement of Fam3a-Nr4a2-Foxa2 pathway in PC1/3 expression and GLP-1 production. Moreover, α-cell-specific Fam3a knockout (Fam3aα-/-) mice were constructed to evaluate the metabolic variables and hormone levels under normoglycemic, high-fat diet (HFD)-fed and streptozotocin (STZ)-induced diabetic conditions. Exendin 9-39 (Ex9), a GLP-1 receptor antagonist, was used to investigate GLP-1 paracrine effects in Fam3aα-/- mice and in their primary islets. RESULTS: Compared with wild-type mice, pancreatic and plasma active GLP-1 levels were increased in Fam3a-/- mice. Analysis of human islet scRNA-seq datasets showed a significant negative correction between FAM3A and PCSK1 in α-cells. Fam3a knockdown upregulated PC1/3 expression and GLP-1 production in αTC1.9 cells, while Fam3a overexpression displayed inverse effects. Transcriptomic analysis identified Nr4a2 as a key downstream mediator of Fam3a, and Nr4a2 expression in αTC1.9 cells was downregulated and upregulated by Fam3a knockdown and overexpression, respectively. Nr4a2 silencing increased PC1/3 expression, albeit Nr4a2 did not directly bind to Pcsk1 promoter. Instead, Nr4a2 formed a complex with Foxa2 to facilitate Fam3a-mediated Foxa2 nuclear translocation. Foxa2 negatively regulated PC1/3 expression and GLP-1 production. Besides, Foxa2 inhibited the transcriptional activity of Pcsk1 promoter at specific binding sites 10 and 6, and this inhibition was intensified by Nr4a2 in αTC1.9 cells. Compared with Flox/cre littermates, improved glucose tolerance, increased active GLP-1 level in pancreas and plasma, upregulated plasma insulin level in response to glucose, and decreased plasma glucagon level were observed in Fam3aα-/- mice. Primary islets isolated from Fam3aα-/- mice also showed an increase in active GLP-1 and insulin release. In addition, the insulinotropic effect of intra-islet GLP-1 were blocked by Ex9 in Fam3aα-/- mice and in their primary islets. Similarly, HFD-fed Fam3aα-/- mice also exhibited an improved glucose tolerance. Both HFD-fed and STZ-induced diabetic Fam3aα-/- mice showed an increased pancreatic active GLP-1 level, an elevated plasma insulin level and a reduced plasma glucagon level. CONCLUSIONS: Fam3a deficiency in α-cells enhances pancreatic GLP-1 production to improve ß-cell function via paracrine signaling in an Nr4a2-Foxa2-PC1/3-dependent manner. Our study unveils a novel strategy for reprogramming α-cell proglucagon processing output from glucagon to GLP-1 and deepen the understanding of crosstalk between α-cells and ß-cells.

2.
Acta Pharmacol Sin ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294445

RESUMO

Sodium-glucose co-transporter 2 (SGLT2) inhibitor (SGLT2i) is a novel class of anti-diabetic drug, which has displayed a promising benefit for non-alcoholic fatty liver disease (NAFLD). In this study, we investigated the protective effects of SGLT2i against NAFLD and the underlying mechanisms. The db/db mice and western diet-induced NAFLD mice were treated with dapagliflozin (1 mg·kg-1·d-1, i.g.) or canagliflozin (10 mg·kg-1·d-1, i.g.) for 8 weeks. We showed that the SGLT2i significantly improved NAFLD-associated metabolic indexes, and attenuated hepatic steatosis and fibrosis. Notably, SGLT2i reduced the levels of pro-inflammatory cytokines and chemokines, downregulated M1 macrophage marker expression and upregulated M2 macrophage marker expression in liver tissues. In cultured mouse bone marrow-derived macrophages and human peripheral blood mononuclear cell-derived macrophages, the SGLT2i (10, 20 and 40 µmol/L) significantly promoted macrophage polarization from M1 to M2 phenotype. RNA sequencing, Seahorse analysis and liquid chromatography-tandem mass spectrometry analysis revealed that the SGLT2i suppressed glycolysis and triggered metabolic reprogramming in macrophages. By using genetic manipulation and pharmacological inhibition, we identified that the SGLT2i targeted PFKFB3, a key enzyme of glycolysis, to modulate the macrophage polarization of M1 to M2 phenotype. Using a co-culture of macrophages with hepatocytes, we demonstrated that the SGLT2i inhibited lipogenesis in hepatocytes via crosstalk with macrophages. In conclusion, this study highlights a potential therapeutic application for repurposing SGLT2i and identifying a potential target PFKFB3 for NAFLD treatment.

3.
Sci Rep ; 14(1): 16860, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39043754

RESUMO

HRB500E rebar is a low-alloy high-strength steel with excellent mechanical properties and good plasticity but suffers from deficient corrosion resistance. This can be solved by adding trace elements, including rare earth elements. Herein, the corrosion-resistant behavior of rebar was evaluated by weightlessness testing and electrochemical measurements, and the effects of Ce on the structural evolution of the corrosion product layer were investigated by scanning electron microscopy (SEM), Electron Probe X-ray Micro-Analyzer (EPMA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results showed that adding Ce to the rebar improved the densification of the reinforcing surface corrosion products, as well as reduced the corrosion rate of the experimental rebar. Compared to C0 sample without Ce, the rebar sample containing 0.044 wt.% Ce displayed increased Ecorr by 0.051 V, decreased Icorr by 15.573 mA cm-2, enhanced Rc of the corrosion product layer by 112.71 Ω cm2, incremented α-FeOOH content in the corrosion product layer, and boosted ratio of α/γ* in the corrosion product layer by 10.11%. Furthermore, the oxide (CeO2) formed by Ce in the corrosion layer of the rebar bar surface existed in the rust layer, resulting in a stable corrosion product layer with improved blocking ability of the corrosive medium. Overall, the addition of Ce at certain ratios looks promising to produce HRB500E rebar with excellent corrosion resistance and extended service life under harsh conditions.

4.
Chemistry ; 30(45): e202401853, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38825564

RESUMO

Phosphaphenalenes, extended π conjugates with the incorporation of phosphorus, are attractive avenues towards molecular materials for the applications in organic electronics, but their electron accepting ability have not been investigated. Herein we present systematic studies on the reductive behavior of a representative phosphaphenalene and its oxide by chemical and electrochemical methods. The chemical reduction of the phosphaphenalene by alkali metals reveals the facile P-C bond cleavage to form phosphaphenalenide anion, which functions as a transfer block for structure modification on the phosphorus atom. In contrast, the pentavalent P-oxide reacts with one or two equivalents of elemental sodium to form stable radical anion and dianion salts, respectively.

5.
Langenbecks Arch Surg ; 409(1): 138, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38676783

RESUMO

PURPOSE: Treating an infiltration of the recurrent laryngeal nerve (RLN) by thyroid carcinoma remains a subject of ongoing debate. Therefore, this study aims to provide a novel strategy for intraoperative phenosurgical management of RLN infiltrated by thyroid carcinoma. METHODS: Forty-two patients with thyroid carcinoma infiltrating the RLN were recruited for this study and divided into three groups. Group A comprised six individuals with medullary thyroid cancer who underwent RLN resection and arytenoid adduction. Group B consisted of 29 differentiated thyroid cancer (DTC)patients who underwent RLN resection and ansa cervicalis (ACN)-to-RLN anastomosis. Group C included seven patients whose RLN was preserved. RESULTS: The videostroboscopic analysis and voice assessment collectively indicated substantial improvements in voice quality for patients in Groups A and B one year post-surgery. Additionally, the shaving technique maintained a normal or near-normal voice in Group C one year post-surgery. CONCLUSION: The new intraoperative phonosurgical strategy is as follows: Resection of the affected RLN and arytenoid adduction is required in cases of medullary or anaplastic carcinoma, regardless of preoperative RLN function. Suppose RLN is found infiltrated by well-differentiated thyroid cancer (WDTC) during surgery, and the RLN is preoperatively paralyzed, we recommend performing resection the involved RLN and ACN-to-RLN anastomosis immediately during surgery. If vocal folds exhibit normal mobility preoperatively, the MACIS scoring system is used to assess patient risk stratification. When the MACIS score > 6.99, resection of the involved RLN and immediate ACN-to-RLN anastomosis were performed. RLN preservation was limited to patients with MACIS scores ≤ 6.99.


Assuntos
Nervo Laríngeo Recorrente , Neoplasias da Glândula Tireoide , Tireoidectomia , Humanos , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Nervo Laríngeo Recorrente/cirurgia , Tireoidectomia/métodos , Paralisia das Pregas Vocais/etiologia , Paralisia das Pregas Vocais/cirurgia , Idoso , Qualidade da Voz , Invasividade Neoplásica/patologia , Resultado do Tratamento
6.
Diabetes ; 73(6): 926-940, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471012

RESUMO

Sodium-glucose cotransporter 2 inhibitors, efficacious antidiabetic agents that have cardiovascular and renal benefits, can promote pancreatic ß-cell regeneration in type 2 diabetic mice. However, the underlying mechanism remains unclear. In this study, we aimed to use multiomics to identify the mediators involved in ß-cell regeneration induced by dapagliflozin. We showed that dapagliflozin lowered blood glucose level, upregulated plasma insulin level, and increased islet area in db/db mice. Dapagliflozin reshaped gut microbiota and modulated microbiotic and plasmatic metabolites related to tryptophan metabolism, especially l-tryptophan, in the diabetic mice. Notably, l-tryptophan upregulated the mRNA level of glucagon-like peptide 1 (GLP-1) production-related gene (Gcg and Pcsk1) expression and promoted GLP-1 secretion in cultured mouse intestinal L cells, and it increased the supernatant insulin level in primary human islets, which was eliminated by GPR142 antagonist. Transplant of fecal microbiota from dapagliflozin-treated mice, supplementation of l-tryptophan, or treatment with dapagliflozin upregulated l-tryptophan, GLP-1, and insulin or C-peptide levels and promoted ß-cell regeneration in db/db mice. Addition of exendin 9-39, a GLP-1 receptor (GLP-1R) antagonist, or pancreatic Glp1r knockout diminished these beneficial effects. In summary, treatment with dapagliflozin in type 2 diabetic mice promotes ß-cell regeneration by upregulating GLP-1 production, which is mediated via gut microbiota and tryptophan metabolism.


Assuntos
Compostos Benzidrílicos , Microbioma Gastrointestinal , Peptídeo 1 Semelhante ao Glucagon , Glucosídeos , Células Secretoras de Insulina , Regeneração , Triptofano , Animais , Compostos Benzidrílicos/farmacologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Triptofano/metabolismo , Camundongos , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Regeneração/efeitos dos fármacos , Humanos , Masculino , Insulina/metabolismo , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/microbiologia , Camundongos Endogâmicos C57BL , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Diabetes Mellitus Experimental/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo
7.
Nat Commun ; 14(1): 3718, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349291

RESUMO

Developing catalysts with both useful enantioselectivities and million turnover numbers (TONs) for asymmetric hydrogenation of ketones is attractive for industrial production of high-value bioactive chiral entities but remains a challenging. Herein, we report an ultra-efficient anionic Ir-catalyst integrated with the concept of multidentate ligation for asymmetric hydrogenation of ketones. Biocatalysis-like efficacy of up to 99% ee (enantiomeric excess), 13,425,000 TON (turnover number) and 224 s-1 TOF (turnover frequency) were documented for benchmark acetophenone. Up to 1,000,000 TON and 99% ee were achieved for challenging pyridyl alkyl ketone where at most 10,000 TONs are previously reported. The anionic Ir-catalyst showed a novel preferred ONa/MH instead of NNa/MH bifunctional mechanism. A selective industrial route to enantiopure nicotine has been established using this anionic Ir-catalyst for the key asymmetric hydrogenation step at 500 kg batch scale, providing 40 tons scale of product.


Assuntos
Cetonas , Nicotina , Catálise , Biocatálise , Hidrogenação
8.
J Phys Chem Lett ; 14(17): 4033-4041, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37093648

RESUMO

Designing an active and selective catalyst for nonoxidative conversion of methane under mild conditions is critical for natural gas utilization as a chemical feedstock. Here, we demonstrate that the origin of the selective nonoxidative conversion of methane by the titanium carbide supported nickel cluster arises from the formation of a nickel carbide site under the reaction conditions, which could stabilize the CHx intermediate to facilitate the C-C coupling, but further coking is rather limited. The reaction mechanism reveals that the C2 products can be formed via a key -CHx-CH3 intermediate. In addition, we demonstrate that boration of the nickel cluster site can improve the methane conversion toward C2 products. That higher activity and selectivity from the moderate rise in d orbital energy levels can therefore be considered as a descriptor of the catalyst effectiveness. These findings provide an understanding of the dynamic behavior of the single nickel cluster toward methane conversion to C2 products and guidance for their future rational design.

9.
Diabetes ; 72(5): 599-610, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36826938

RESUMO

Dysfunction of glucagon-secreting α-cells participates in the progression of diabetes, and glucagon receptor (GCGR) antagonism is regarded as a novel strategy for diabetes therapy. GCGR antagonism upregulates glucagon and glucagon-like peptide 1 (GLP-1) secretion and, notably, promotes ß-cell regeneration in diabetic mice. Here, we aimed to clarify the role of GLP-1 receptor (GLP-1R) activated by glucagon and/or GLP-1 in the GCGR antagonism-induced ß-cell regeneration. We showed that in db/db mice and type 1 diabetic wild-type or Flox/cre mice, GCGR monoclonal antibody (mAb) improved glucose control, upregulated plasma insulin level, and increased ß-cell area. Notably, blockage of systemic or pancreatic GLP-1R signaling by exendin 9-39 (Ex9) or Glp1r knockout diminished the above effects of GCGR mAb. Furthermore, glucagon-neutralizing antibody (nAb), which prevents activation of GLP-1R by glucagon, also attenuated the GCGR mAb-induced insulinotropic effect and ß-cell regeneration. In cultured primary mouse islets isolated from normal mice and db/db mice, GCGR mAb action to increase insulin release and to upregulate ß-cell-specific marker expression was reduced by a glucagon nAb, by the GLP-1R antagonist Ex9, or by a pancreas-specific Glp1r knockout. These findings suggest that activation of GLP-1R by glucagon participates in ß-cell regeneration induced by GCGR antagonism in diabetic mice. ARTICLE HIGHLIGHTS: Glucagon receptor (GCGR) antagonism promotes ß-cell regeneration in type 1 and type 2 diabetic mice and in euglycemic nonhuman primates. Glucagon and glucagon-like peptide 1 (GLP-1) can activate the GLP-1 receptor (GLP-1R), and their levels are upregulated following GCGR antagonism. We investigated whether GLP-1R activated by glucagon and/or GLP-1 contributed to ß-cell regeneration induced by GCGR antagonism. We found that blockage of glucagon-GLP-1R signaling attenuated the GCGR monoclonal antibody-induced insulinotropic effect and ß-cell regeneration in diabetic mice. Our study reveals a novel mechanism of ß-cell regeneration and uncovers the communication between α-cells and ß-cells in regulating ß-cell mass.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Glucagon , Camundongos , Animais , Glucagon/metabolismo , Receptores de Glucagon/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Diabetes Mellitus Experimental/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Insulina/metabolismo , Células Secretoras de Glucagon/metabolismo , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/metabolismo , Regeneração
10.
Diabetes Metab Res Rev ; 39(3): e3607, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36565185

RESUMO

AIMS: Sodium-glucose co-transporter 2 inhibitors, including dapagliflozin, improve ß cell function in type 2 diabetic individuals. Whether dapagliflozin can protect islet microvascular endothelial cells (IMECs) and thus contribute to the improvement of ß cell function remains unknown. MATERIALS AND METHODS: The db/db mice were treated with dapagliflozin or vehicle for 6 weeks. ß cell function, islet capillaries and the levels of inflammatory chemokines in IMECs were detected. The mouse IMEC cell line MS-1 cells were incubated with palmitate and/or dapagliflozin for 24 h. Angiogenesis and inflammatory chemokine levels were evaluated, and the involved signalling pathways were analysed. The mouse ß cell line MIN6 cells, in the presence or absence of co-culture with MS-1 cells, were treated with palmitate and/or dapagliflozin for 24 h. The expression of ß cell specific markers and insulin secretion in MIN6 cells were determined. RESULTS: Dapagliflozin significantly improved ß cell function, increased islet capillaries and decreased the levels of inflammatory chemokines of IMECs in db/db mice. In the palmitate-treated MS-1 cells, angiogenesis was enhanced and the levels of inflammatory chemokines were downregulated by dapagliflozin. Either a PI3K inhibitor or mTOR inhibitor eliminated the dapagliflozin-mediated effects. Importantly, dapagliflozin attenuated the palmitate-induced downregulation of ß cell function-related gene expression and insulin secretion in MIN6 cells co-cultured with MS-1 cells but not in those on mono-culture. CONCLUSIONS: Dapagliflozin restores islet vascularisation and attenuates the inflammation of IMECs in type 2 diabetic mice. The dapagliflozin-induced improvement of ß cell function is at least partially accounted for by its beneficial effects on IMECs in a PI3K/Akt-mTOR-dependent manner.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ilhotas Pancreáticas , Doenças Vasculares , Camundongos , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais , Fosfatidilinositol 3-Quinases/metabolismo , Ilhotas Pancreáticas/metabolismo , Compostos Benzidrílicos/farmacologia , Doenças Vasculares/metabolismo , Palmitatos/metabolismo
11.
Asian J Androl ; 25(3): 331-338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35848706

RESUMO

Male diabetic individuals present a marked impairment in fertility; however, knowledge regarding the pathogenic mechanisms and therapeutic strategies is unsatisfactory. The new hypoglycemic drug dapagliflozin has shown certain benefits, such as decreasing the risk of cardiovascular and renal events in patients with diabetes. Even so, until now, the effects and underlying mechanisms of dapagliflozin on diabetic male infertility have awaited clarification. Here, we found that dapagliflozin lowered blood glucose levels, alleviated seminiferous tubule destruction, and increased sperm concentrations and motility in leptin receptor-deficient diabetic db/db mice. Moreover, the glucagon-like peptide-1 receptor (GLP-1R) antagonist exendin (9-39) had no effect on glucose levels but reversed the protective effects of dapagliflozin on testicular structure and sperm quality in db/db mice. We also found that dapagliflozin inhibited the testicular apoptotic process by upregulating the expression of the antiapoptotic protein B-cell lymphoma 2 (BCL2) and X-linked inhibitor of apoptosis protein (XIAP) and inhibiting oxidative stress by enhancing the antioxidant status, including total antioxidant capacity, total superoxide dismutase (SOD) activity, and glutathione peroxidase (GPx) activity, as well as decreasing the level of 4-hydroxynonenal (4-HNE). Exendin (9-39) administration partially reversed these effects. Furthermore, dapagliflozin upregulated the glucagon-like peptide-1 (GLP-1) level in plasma and GLP-1R expression by promoting AKT8 virus oncogene cellular homolog (Akt) phosphorylation in testicular tissue. Exendin (9-39) partially inhibited Akt phosphorylation. These results suggest that dapagliflozin protects against diabetes-induced spermatogenic dysfunction via activation of the GLP-1R/phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Our results indicate the potential effects of dapagliflozin against diabetes-induced spermatogenic dysfunction.


Assuntos
Diabetes Mellitus , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Masculino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antioxidantes , Fosfatidilinositol 3-Quinases/metabolismo , Sêmen/metabolismo
12.
BMC Genomics ; 23(1): 830, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517766

RESUMO

BACKGROUND: Structural variations (SVs) have recently become a topic of great interest in the area of genetic diversity and trait regulation. As genomic sequencing technologies have rapidly advanced, longer reads have been used to identify SVs at high resolution and with increased accuracy. It is important to choose a suitable sequencing platform and appropriate sequencing depth for SV detection in the pear genome. RESULTS: In this study, two types of long reads from sequencing platforms, continuous long reads from Pacific Biosciences (PB-CLR) and long reads from Oxford Nanopore Technologies (ONT), were used to comprehensively analyze and compare SVs in the pear genome. The mapping rate of long reads was higher when the program Minimap2 rather than the other three mapping tools (NGMLR, LRA and Winnowmap2) was used. Three SV detection programs (Sniffles_v2, CuteSV, and Nanovar) were compared, and Nanovar had the highest sensitivity in detecting SVs at low sequencing depth (10-15×). A sequencing depth of 15× was suitable for SV detection in the pear genome using Nanovar. SVs detected by Sniffles_v2 and CuteSV with ONT reads had the high overlap with presence/absence variations (PAVs) in the pear cultivars 'Bartlett' and 'Dangshansuli', both of them with 38% of insertions and 55% of deletions overlapping with PAVs at sequencing depth of 30×. For the ONT sequencing data, over 37,526 SVs spanning ~ 28 Mb were identified by all three software packages for the 'Bartlett' and 'Dangshansuli' genomes. Those SVs were annotated and combined with transcriptome profiles derived from 'Bartlett' and 'Dangshansuli' fruit flesh at 60 days after cross-pollination. Several genes related to levels of sugars, acid, stone cells, and aromatic compounds were identified among the SVs. Transcription factors were then predicted among those genes, and results included bHLH, ERF, and MYB genes. CONCLUSION: SV detection is of great significance in exploring phenotypic differences between pear varieties. Our study provides a framework for assessment of different SV software packages and sequencing platforms that can be applied in other plant genome studies. Based on these analyses, ONT sequencing data was determined to be more suitable than PB-CLR for SV detection in the pear genome. This analysis model will facilitate screening of genes related to agronomic traits in other crops.


Assuntos
Nanoporos , Pyrus , Pyrus/genética , Análise de Sequência , Mapeamento Cromossômico , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Variação Estrutural do Genoma , Análise de Sequência de DNA/métodos
13.
Chem Sci ; 13(41): 12114-12121, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36349089

RESUMO

Inducing the surface enrichment of active noble metal can not only help to stabilize the catalyst but also modify the catalytic performance of the catalyst through electronic and geometric effects. Herein, we report the in situ surface enrichment of Ir on IrRu alloy during the oxygen evolution reaction (OER). The surface enrichment of Ir was probed by ex situ high-resolution transmission electron microscopy (HRTEM), in situ X-ray absorption spectroscopy (XAS), and electrochemical Cu stripping, leading to complementary characterizations of the dynamic reconstruction of the IrRu alloy during OER. Guided by the density functional theory (DFT), an IrRu alloy with low Ir content (20 wt%) was constructed, which displayed a low overpotential of only 230 mV to deliver an OER current density of 10 mA cm-2 in 0.1 M HClO4 solution and maintained stable performance for over 20 h. To investigate the practical application potential, a proton exchange membrane (PEM) water electrolyzer using the IrRu alloy as the anode catalyst was assembled, which required a low cell voltage of only 1.48 V to generate a current density of 1 A cm-2.

14.
Nat Commun ; 13(1): 7207, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418292

RESUMO

Osteosarcoma (OS) is a primary malignant bone tumor that most commonly affects children, adolescents, and young adults. Here, we comprehensively analyze genomic, epigenomic and transcriptomic data from 121 OS patients. Somatic mutations are diverse within the cohort, and only TP53 is significantly mutated. Through unsupervised integrative clustering of the multi-omics data, we classify OS into four subtypes with distinct molecular features and clinical prognosis: (1) Immune activated (S-IA), (2) Immune suppressed (S-IS), (3) Homologous recombination deficiency dominant (S-HRD), and (4) MYC driven (S-MD). MYC amplification with HR proficiency tumors is identified with a high oxidative phosphorylation signature resulting in resistance to neoadjuvant chemotherapy. Potential therapeutic targets are identified for each subtype, including platinum-based chemotherapy, immune checkpoint inhibitors, anti-VEGFR, anti-MYC and PARPi-based synthetic lethal strategies. Our comprehensive integrated characterization provides a valuable resource that deepens our understanding of the disease, and may guide future clinical strategies for the precision treatment of OS.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Adulto Jovem , Adolescente , Criança , Humanos , Osteossarcoma/genética , Osteossarcoma/terapia , Genômica/métodos , Transcriptoma , Platina , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética
15.
Plant Biotechnol J ; 20(10): 1940-1955, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35718938

RESUMO

Interspecific breeding in cotton takes advantage of genetic recombination among desirable genes from different parental lines. However, the expression new alleles (ENAs) from crossovers within genic regions and their significance in fibre length (FL) improvement are currently not understood. Here, we generated resequencing genomes of 191 interspecific backcross inbred lines derived from CRI36 (Gossypium hirsutum) × Hai7124 (Gossypium barbadense) and 277 dynamic fibre transcriptomes to identify the ENAs and extremely expressed genes (eGenes) potentially influencing FL, and uncovered the dynamic regulatory network of fibre elongation. Of 35 420 eGenes in developing fibres, 10 366 ENAs were identified and preferentially distributed in chromosomes subtelomeric regions. In total, 1056-1255 ENAs showed transgressive expression in fibres at 5-15 dpa (days post-anthesis) of some BILs, 520 of which were located in FL-quantitative trait locus (QTLs) and GhFLA9 (recombination allele) was identified with a larger effect for FL than GhFLA9 of CRI36 allele. Using ENAs as a type of markers, we identified three novel FL-QTLs. Additionally, 456 extremely eGenes were identified that were preferentially distributed in recombination hotspots. Importantly, 34 of them were significantly associated with FL. Gene expression quantitative trait locus analysis identified 1286, 1089 and 1059 eGenes that were colocalized with the FL trait at 5, 10 and 15 dpa, respectively. Finally, we verified the Ghir_D10G011050 gene linked to fibre elongation by the CRISPR-cas9 system. This study provides the first glimpse into the occurrence, distribution and expression of the developing fibres genes (especially ENAs) in an introgression population, and their possible biological significance in FL.


Assuntos
Fibra de Algodão , Gossypium , Alelos , Gossypium/genética , Gossypium/metabolismo , Melhoramento Vegetal , Locos de Características Quantitativas/genética
16.
J Healthc Eng ; 2021: 1765404, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900177

RESUMO

Knee osteoarthritis (OA) is one of the most common musculoskeletal disorders. OA diagnosis is currently conducted by assessing symptoms and evaluating plain radiographs, but this process suffers from the subjectivity of doctors. In this study, we retrospectively compared five commonly used machine learning methods, especially the CNN network, to predict the real-world X-ray imaging data of knee joints from two different hospitals using Kellgren-Lawrence (K-L) grade of knee OA to help doctors choose proper auxiliary tools. Furthermore, we present attention maps of CNN to highlight the radiological features affecting the network decision. Such information makes the decision process transparent for practitioners, which builds better trust towards such automatic methods and, moreover, reduces the workload of clinicians, especially for remote areas without enough medical staff.


Assuntos
Doenças Musculoesqueléticas , Osteoartrite do Joelho , Humanos , Aprendizado de Máquina , Osteoartrite do Joelho/diagnóstico por imagem , Estudos Retrospectivos , Carga de Trabalho
17.
Nat Commun ; 12(1): 6806, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815417

RESUMO

Single-atom catalysts (SACs) have been applied in many fields due to their superior catalytic performance. Because of the unique properties of the single-atom-site, using the single atoms as catalysts to synthesize SACs is promising. In this work, we have successfully achieved Co1 SAC using Pt1 atoms as catalysts. More importantly, this synthesis strategy can be extended to achieve Fe and Ni SACs as well. X-ray absorption spectroscopy (XAS) results demonstrate that the achieved Fe, Co, and Ni SACs are in a M1-pyrrolic N4 (M= Fe, Co, and Ni) structure. Density functional theory (DFT) studies show that the Co(Cp)2 dissociation is enhanced by Pt1 atoms, thus leading to the formation of Co1 atoms instead of nanoparticles. These SACs are also evaluated under hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), and the nature of active sites under HER are unveiled by the operando XAS studies. These new findings extend the application fields of SACs to catalytic fabrication methodology, which is promising for the rational design of advanced SACs.

18.
Nat Genet ; 53(9): 1385-1391, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373642

RESUMO

Cotton produces natural fiber for the textile industry. The genetic effects of genomic structural variations underlying agronomic traits remain unclear. Here, we generate two high-quality genomes of Gossypium hirsutum cv. NDM8 and Gossypium barbadense acc. Pima90, and identify large-scale structural variations in the two species and 1,081 G. hirsutum accessions. The density of structural variations is higher in the D-subgenome than in the A-subgenome, indicating that the D-subgenome undergoes stronger selection during species formation and variety development. Many structural variations in genes and/or regulatory regions potentially influencing agronomic traits were discovered. Of 446 significantly associated structural variations, those for fiber quality and Verticillium wilt resistance are located mainly in the D-subgenome and those for yield mainly in the A-subgenome. Our research provides insight into the role of structural variations in genotype-to-phenotype relationships and their potential utility in crop improvement.


Assuntos
Fibra de Algodão/análise , Genoma de Planta/genética , Gossypium/genética , Gossypium/fisiologia , Agricultura/métodos , Ligação Genética , Variação Genética/genética , Genótipo , Gossypium/classificação , Fenótipo , Locos de Características Quantitativas/genética , Análise de Sequência de DNA , Indústria Têxtil/métodos
19.
Front Oncol ; 11: 642134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34168981

RESUMO

Osteosarcoma is the most common primary malignant bone tumor, and there are few ideal clinically available drugs. The bromodomain and extraterminal domain (BET) protein is an emerging target for aggressive cancer, but therapies targeting the BET in osteosarcoma have been unsuccessful in clinical trials to date, and further exploration of specific BET inhibitors is of great significance. In our study, we demonstrated that NHWD-870, a potent BET inhibitor in a phase I clinical trial, significantly inhibited tumor proliferation and promoted cell apoptosis by reversing the oncogenic signature in osteosarcoma. More importantly, we identified NHWD-870 impeded binding of BRD4 to the promoter of GP130 leading to diminished activation of JAK/STAT3 signaling pathway. Furthermore, GP130 knockdown significantly sensitizes the chemosensitivity in vitro. In OS cell-derived xenografts, NHWD-870 effectively inhibited the growth of osteosarcoma. Beyond that, NHWD-870 effectively inhibited the differentiation and maturation of precursor osteoclasts in vitro and attenuated osteoclast-mediated bone loss in vivo. Finally, we confirmed the efficacy of synthetic lethal effects of NHWD-870 and cisplatin in antagonizing osteosarcoma in a preclinical PDX model. Taken together, these findings demonstrate that NHWD-870, as an effective BET inhibitor, may be a potential candidate for osteosarcoma intervention linked to its STAT3 signaling inhibitory activity. In addition, NHWD-870 appears to be a promising therapeutic strategy for bone-associated tumors, as it interferes with the vicious cycle of tumor progression and bone destruction.

20.
Chem Sci ; 12(20): 7125-7137, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-34123340

RESUMO

The desire for a carbon-free society and the continuously increasing demand for clean energy make it valuable to exploit green ammonia (NH3) synthesis that proceeds via the electrolysis driven Haber-Bosch (eHB) process. The key for successful operation is to develop advanced catalysts that can operate under mild conditions with efficacy. The main bottleneck of NH3 synthesis under mild conditions is the known scaling relation in which the feasibility of N2 dissociative adsorption of a catalyst is inversely related to that of the desorption of surface N-containing intermediate species, which leads to the dilemma that NH3 synthesis could not be catalyzed effectively under mild conditions. The present work offers a new strategy via introducing atomically dispersed Ru onto a single Co atom coordinated with pyrrolic N, which forms RuCo dual single-atom active sites. In this system the d-band centers of Ru and Co were both regulated to decouple the scaling relation. Detailed experimental and theoretical investigations demonstrate that the d-bands of Ru and Co both become narrow, and there is a significant overlapping of t2g and eg orbitals as well as the formation of a nearly uniform Co 3d ligand field, making the electronic structure of the Co atom resemble that of a "free-atom". The "free-Co-atom" acts as a bridge to facilitate electron transfer from pyrrolic N to surface Ru single atoms, which enables the Ru atom to donate electrons to the antibonding π* orbitals of N2, thus resulting in promoted N2 adsorption and activation. Meanwhile, H2 adsorbs dissociatively on the Co center to form a hydride, which can transfer to the Ru site to cause the hydrogenation of the activated N2 to generate N2H x (x = 1-4) intermediates. The narrow d-band centers of this RuCo catalyst facilitate desorption of surface *NH3 intermediates even at 50 °C. The cooperativity of the RuCo system decouples the sites for the activation of N2 from those for the desorption of *NH3 and *N2H x intermediates, giving rise to a favorable pathway for efficient NH3 synthesis under mild conditions.

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