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1.
J Plast Reconstr Aesthet Surg ; 94: 119-127, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776626

RESUMO

BACKGROUND: The efficient resurfacing of multiple adjacent defects (MADs) requires precise reconstructive strategy. Various approaches (e.g., several flap transferring or prelamination of the recipient site) have been reported, but recipient-site impairments, pain, long hospitalization, and low cost-benefit results fatefully considered them as compromise approaches. This study aims to evaluate the feasibility of MADs reconstruction with free multipaddle superficial circumflex iliac artery perforator (SCIAP) flaps. METHODS: From Dec 2015 to Dec 2020, we enrolled patients with upper and lower extremity defects treated with various multipaddle SCIAP flaps (2-paddle, 3-paddle, and 4-paddle). Patient demographics and outcomes of each group were collected. RESULTS: Thirty-two, 21, and 6 patients underwent 2-paddle, 3-paddle, and 4-paddle SCIAP flaps transfers, respectively. All multipaddle SCIAP flaps survived without vascular problems, and the donor sites were closed directly. Except for 3 cases of 2-paddle SCIAP flaps drained by superficial circumflex iliac vein venous return, most cases (n = 56) were drained by venae comitans. Minor complications, including partial flap necrosis (4 cases) and lateral femoral cutaneous nerve palsies (11 cases), were treated conservatively. All patients were satisfied with the reconstructive outcome. CONCLUSION: Multiple adjacent defects reconstruction is still a Gordian knot and lacks a golden standard. The free multipaddle SCIAP flap was demonstrated as a promising alternative, not only enriching its versatility but also initially highlighting the "replace need with need" reconstructive demand.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Retalho Perfurante/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Idoso , Artéria Ilíaca/cirurgia , Estudos de Viabilidade , Estudos Retrospectivos , Retalhos de Tecido Biológico , Adulto Jovem , Adolescente , Extremidade Inferior/cirurgia , Extremidade Superior/cirurgia , Sobrevivência de Enxerto
2.
J Sep Sci ; 47(11): e2400145, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822225

RESUMO

In this study, a combination approach involving macroporous resin (MR) column chromatography and gradient countercurrent chromatography (CCC) was employed to enrich and purify bufadienolides from the roots and rhizomes of Helleborus thibetanus Franch. Initially, a D101 MR-packed column chromatography was utilized for fractionation and enrichment of the bufadienolides, which were effectively eluted from the column using a 60% ethanol solution. CCC was subsequently introduced to separate the enriched product using the ethyl acetate/n-butanol/water (EBuWat, 4:1:5, v/v) and EBuWat (5:0:5, v/v) solvent systems in a gradient elution mode. As results, five bufadienolides, including 6.1 mg of hellebrigenin-3-O-ß-D-glucoside (1), 2.2 mg of tigencaoside A (2), 8.3 mg of deglucohellebrin (3), 3.5 mg of 14 ß-hydroxy-3ß-[ß-D-glucopyranosyl-(1→6)-(ß-D-glucopyranosyl)oxy]-5α-bufa-20,22-dienolide (4), and 3.0 mg of 14ß-hydroxy-3ß-[(ß-D-glucopyranosyl)oxy]-5α-bufa-20,22-dienolide (5), were effectively separated from 300 mg of the enriched product. The respective high-performance liquid chromatography purities were as follows: 95.2%, 75.8%, 85.7%, 82.3%, and 92.8%. This study provides valuable insights for the efficient enrichment and separation of bufadienolides from Helleborus thibetanus Franch.


Assuntos
Bufanolídeos , Distribuição Contracorrente , Helleborus , Distribuição Contracorrente/métodos , Bufanolídeos/química , Bufanolídeos/isolamento & purificação , Helleborus/química , Porosidade , Resinas Sintéticas/química , Cromatografia Líquida de Alta Pressão , Raízes de Plantas/química
3.
Chem Commun (Camb) ; 60(44): 5735-5738, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38742637

RESUMO

Electroreductive ring-opening carboxylation of styrene carbonates with CO2 to achieve dicarboxylic acids and/or ß-hydroxy acids has been developed via the selective cleavage of the C(sp3)-O bond in cyclic carbonates. The product selectivity is probably determined by the stability and reactivity of the key benzylic radical and carbanion intermediate.

4.
Dalton Trans ; 53(21): 9198-9206, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38743042

RESUMO

The polymerization mechanism of 2-vinylpyridine catalyzed by cationic yttrium complexes with diverse ancillary ligands, specifically [L1Y(CH2SiMe3)(THF)]+ [L1 = (2,6-Et2C6H3)NC(Me)CHC(Me)N(2,6-Et2C6H3)] (Y-1), [L2Y(CH2SiMe3)(THF)]+ [L2 = (2,6-Cl2C6H3)NC(Me)CHC(Me)N(2,6-Cl2C6H3)] (Y-2), and [L3Y(CH2SiMe3)(THF)]+ [L3 = (2,6-C6H5)NC(Me)CHC(Me)N(2,6-iPr2C6H3)] (Y-3), was studied using density functional theory (DFT) calculations. Having achieved an agreement between theory and experiment, it is found that isotactic selectivity induced by Y-1 or Y-2 results from a combination of smaller deformation of the catalyst and stronger electronic effects. Conversely, the Y-3 complex exhibits comparable energy barriers for proceeding via either isotactic or syndiotactic pathways, aligning with the production of atactic polymers as seen experimentally. To examine the steric effects on the kinetic and thermodynamic properties, a computational model of an analogue complex [L4Y(CH2SiMe3)(THF)]+ [L4 = (2,6-Cl2C6H3)NC(Me)CHC(Me)N(iPr2C6H3)] (Y-4), featuring increased steric hindrance, was analyzed. Distortion-interaction and topographic steric map analyses further affirmed that steric hindrance significantly influences stereoselectivity. A direct relationship was identified between the energy barriers of isotactic insertion transition states and the bulkiness of ancillary ligands; greater distortion energy of the catalyst correlates with higher barriers for isotactic polymerization. These findings enhance the mechanistic comprehension of 2-vinylpyridine polymerization and are expected to contribute valuable insights for the improvement of catalytic polymerization systems of 2-vinylpyridine.

5.
Mol Genet Genomics ; 299(1): 48, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700639

RESUMO

Intramuscular fat (IMF) is a critical factor in beef quality. IMF is mainly distributed between muscle fibres and its accumulation can affect the marbling and meat quality of beef. IMF formation and deposition is a complex process and in recent years a group of non-coding RNAs (ncRNAs), known as circRNAs, have been discovered to play an important role in regulating intramuscular fat deposition. CircRNAs form a covalent loop structure after reverse splicing of precursor mRNAs. They can act by adsorbing miRNAs, thereby reducing their repressive effects on downstream target genes. Based on high-throughput sequencing of circRNAs in intramuscular fat of Qinchuan and Japanese black cattle, we identified a novel circSSBP2 that is differentially expressed between the two species and associated with adipogenesis. We show that circSSBP2 knockdown promotes bovine intramuscular preadipocyte proliferation, whereas overexpression inhibits bovine intramuscular preadipocyte proliferation. We also show that circSSBP2 can act as a molecular sponge for miR-2400 and that miR-2400 overexpression promotes bovine intramuscular preadipocyte proliferation. Furthermore, N-myc downstream-regulated gene 1 (NDRG1) was identified as a direct target gene of miR-2400, and NDRG1 interference promoted the proliferation of bovine intramuscular preadipocytes. In conclusion, our results suggest that circSSBP2 inhibits the proliferation of bovine intramuscular preadipocytes by regulating the miR-2400/NDRG1 axis.


Assuntos
Adipócitos , Adipogenia , Proteínas de Ciclo Celular , Proliferação de Células , Peptídeos e Proteínas de Sinalização Intracelular , MicroRNAs , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Bovinos , Adipócitos/metabolismo , Adipócitos/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Adipogenia/genética , RNA Circular/genética , Regulação da Expressão Gênica
6.
PeerJ Comput Sci ; 10: e1832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435584

RESUMO

Reliable point cloud data (PCD) generated by LiDAR are crucial to perceiving surroundings when autonomous driving systems are a concern. However, adverse weather conditions can impact the detection range of LiDAR, resulting in a significant amount of noisy data that substantially deteriorates the quality of PCD. Point cloud denoising algorithms used for challenging weather conditions suffer from poor accuracy and slow inferences. The manuscript proposes a Series Attention Fusion Denoised Network (SAFDN) based on a semantic segmentation model in real-time, called PP-LiteSeg. The proposed approach provides two key components to the model. The insufficient feature extraction issue in the general-purpose segmentation models is first addressed when dealing with objects with more noise, so the WeatherBlock module is introduced to replace the original layer used for feature extraction. Hence, this module employs dilated convolutions to enhance the receptive field and extract multi-scale features by combining various convolutional kernels. The Series Attention Fusion Module (SAFM) is presented as the second component of the model to tackle the problem of low segmentation accuracy in rainy and foggy weather conditions. The SAFM sequentially applies channel and spatial attention mechanisms to enhance the model's sensitivity to crucial features. Furthermore, weighted feature fusion is employed to enhance the model's efficiency in integrating low-level and high-level feature information configurations. Experimental evaluations were conducted on the publicly available DENSE dataset. The results demonstrate that the improved model achieved an 11.1% increase in denoising accuracy measured by MIOU and an inference speed of 205.06 FPS when compared to the PP-LiteSeg model. As a result, the noise recognition accuracy and denoising capability in real-time are enhanced.

7.
Org Lett ; 26(2): 542-546, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38189289

RESUMO

Electrocarboxylation of the C(sp3)-O bond in 1,3-oxazolidin-2-ones with CO2 to achieve ß-amino acids is developed. The C-O bond in substrates can be selectively cleaved via the single electron transfer on the surface of a cathode or through a CO2• - intermediate under additive-free conditions. A great diversity of ß-amino acids can be obtained in a moderate to excellent yield and readily converted to various biologically active compounds.

8.
Dalton Trans ; 52(41): 14790-14796, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37807861

RESUMO

Mechanism-driven catalyst screening could be greatly accelerated by quantitative prediction models of the reaction energy profile. Here, we propose a novel method for molecular representation, taking palladium- and nickel-catalyzed ethylene polymerization as model reactions. The geometric parameters (GPfra) and electron occupancies (EOfra) from the non-ligand fragment of the η3-complex were extracted as the molecular descriptors, followed by constructing the reaction energy profile prediction models on the basis of various regression algorithms. The models showed great accuracy with respect to both theoretical and experimental data. More importantly, the models are convenient for training and utilization. On one hand, all the features were easily captured from the single η3-complex. On the other hand, further investigation also demonstrated that the models could be constructed with a small training sample size. We believe that our featurization method could possibly be generalized to more organometallic reactions and paves the way to efficient catalyst design.

9.
Comput Biol Med ; 163: 107091, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37331099

RESUMO

The accurate segmentation of carotid plaques in ultrasound videos will provide evidence for clinicians to evaluate the properties of plaques and treat patients effectively. However, the confusing background, blurry boundaries and plaque movement in ultrasound videos make accurate plaque segmentation challenging. To address the above challenges, we propose the Refined Feature-based Multi-frame and Multi-scale Fusing Gate Network (RMFG_Net), which captures spatial and temporal features in consecutive video frames for high-quality segmentation results and no manual annotation of the first frame. A spatial-temporal feature filter is proposed to suppress the noise of low-level CNN features and promote the detailed target area. To obtain a more accurate plaque position, we propose a transformer-based cross-scale spatial location algorithm, which models the relationship between adjacent layers of consecutive video frames to achieve stable positioning. To make full use of more detailed and semantic information, multi-layer gated computing is applied to fuse features of different layers, ensuring sufficient useful feature map aggregation for segmentation. Experiments on two clinical datasets demonstrate that the proposed method outperforms other state-of-the-art methods under different evaluation metrics, and it processes images with a speed of 68 frames per second which is suitable for real-time segmentation. A large number of ablation experiments were conducted to demonstrate the effectiveness of each component and experimental setting, as well as the potential of the proposed method in ultrasound video plaque segmentation tasks. The codes can be publicly available from https://github.com/xifengHuu/RMFG_Net.git.


Assuntos
Algoritmos , Benchmarking , Humanos , Ultrassonografia , Movimento , Semântica , Processamento de Imagem Assistida por Computador
10.
Chemistry ; 29(32): e202204073, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-36912894

RESUMO

Electrocarboxylation reaction, which employs organic electrosynthesis to achieve the utilization of CO2 as a carboxylative reagent, provides a powerful and efficient tool for the preparation of organic carboxylic acid. In some electrocarboxylation reactions, CO2 also acts as a promoter to facilitate the desired reaction. This concept mainly highlights recent CO2 -promoted electrocarboxylation reactions via CO2 ⋅- intermediate or transiently protective carboxylation of active intermediate with CO2 .


Assuntos
Dióxido de Carbono , Ácidos Carboxílicos , Indicadores e Reagentes
11.
Int J Mol Sci ; 24(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36835645

RESUMO

The intramuscular fat (or marbling fat) content is an essential economic trait of beef cattle and improves the flavor and palatability of meat. Several studies have highlighted the correlation between long non-coding RNAs (lncRNAs) and intramuscular fat development; however, the precise molecular mechanism remains unknown. Previously, through a high-throughput sequencing analysis, we found a lncRNA and named it a long non-coding RNA BNIP3 (lncBNIP3). The 5' RACE and 3' RACE explored 1945 bp total length of lncBNIP3, including 1621 bp of 5'RACE, and 464 bp of 3'RACE. The nucleoplasmic separation and FISH results explored the nuclear localization of lncBNIP3. Moreover, the tissue expression of lncBNIP3 was higher in the longissimus dorsi muscle, followed by intramuscular fat. Furthermore, down-regulation of lncBNIP3 increased the 5-Ethynyl-2'- deoxyuridine (EdU)-EdU-positive cells. The flow cytometry results showed that the number of cells in the S phase was significantly higher in preadipocytes transfected with si-lncBNIP3 than in the control group (si-NC). Similarly, CCK8 results showed that the number of cells after transfection of si-lncBNIP3 was significantly higher than in the control group. In addition, the mRNA expressions of proliferative marker genes CyclinB1 (CCNB1) and Proliferating Cell Nuclear Antigen (PCNA) in the si-lncBNIP3 group were significantly higher than in the control group. The Western Blot (WB) results also showed that the protein expression level of PCNA transfection of si-lncBNIP3 was significantly higher than in the control group. Similarly, the enrichment of lncBNIP3 significantly decreased the EdU-positive cells in the bovine preadipocytes. The results of flow cytometry and CCK8 assay also showed that overexpression of lncBNIP3 inhibited the proliferation of bovine preadipocytes. In addition, the overexpression of lncBNIP3 significantly inhibited the mRNA expressions of CCNB1 and PCNA. The WB results showed that the overexpression of lncBNIP3 significantly inhibited the expression of the CCNB1 protein level. To further explore the mechanism of lncBNIP3 on the proliferation of intramuscular preadipocytes, RNA-seq was performed after interference with si-lncBNIP3, and 660 differentially expressed genes (DEGs) were found, including 417 up-regulated DEGs and 243 down-regulated DEGs. The KEGG pathway analysis showed that the cell cycle was the most significant pathway for the functional enrichment of DEGs, followed by the DNA replication pathway. The RT-qPCR quantified the expression of twenty DEGs in the cell cycle. Therefore, we speculated that lncBNIP3 regulated intramuscular preadipocyte proliferation through the cell cycle and DNA replication pathways. To further confirm this hypothesis, the cell cycle inhibitor Ara-C was used to inhibit DNA replication of the S phase in intramuscular preadipocytes. Herein, Ara-C and si-lncBNIP3 were simultaneously added to the preadipocytes, and the CCK8, flow cytometry, and EdU assays were performed. The results showed that the si-lncBNIP3 could rescue the inhibitory effect of Ara-C in the bovine preadipocyte proliferation. In addition, lncBNIP3 could bind to the promoter of cell division control protein 6 (CDC6), and down-regulation of lncBNIP3 promoted the transcription activity and the expression of CDC6. Therefore, the inhibitory effect of lncBNIP3 on cell proliferation might be understood through the cell cycle pathway and CDC6 expression. This study provided a valuable lncRNA with functional roles in intramuscular fat accumulation and revealed new strategies for improving beef quality.


Assuntos
RNA Longo não Codificante , Animais , Bovinos , RNA Longo não Codificante/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Adipócitos/metabolismo , Divisão Celular , Proliferação de Células/genética , RNA Mensageiro/metabolismo
12.
Genes (Basel) ; 14(2)2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36833456

RESUMO

Several microRNAs (miRNAs) are known to participate in adipogenesis. However, their role in this process, especially in the differentiation of bovine preadipocytes, remains to be elucidated. This study was intended to clarify the effect of microRNA-33a (miR-33a) on the differentiation of bovine preadipocytes by cell culture, real-time fluorescent quantitative PCR (qPCR), Oil Red staining, BODIPY staining, and Western blotting. The results indicate that overexpression of miR-33a significantly inhibited lipid droplet accumulation and decreased the mRNA and protein expression of adipocyte differentiation marker genes such as peroxisome proliferator-activated receptor gamma (PPARγ), sterol regulatory element-binding protein 1 (SREBP1), and fatty acid-binding protein 4 (FABP4). In contrast, the interference expression of miR-33a promoted lipid droplet accumulation and increased the expression of marker genes. Additionally, miR-33a directly targeted insulin receptor substrate 2 (IRS2) and regulated the phosphorylation level of serine/threonine kinase (Akt). Furthermore, miR-33a inhibition could rescue defects in the differentiation of bovine preadipocytes and the Akt phosphorylation level caused by small interfering IRS2 (si-IRS2). Collectively, these results indicate that miR-33a could inhibit the differentiation of bovine preadipocytes, possibly through the IRS2-Akt pathway. These findings might help develop practical means to improve the quality of beef.


Assuntos
MicroRNAs , Proteínas Proto-Oncogênicas c-akt , Bovinos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Substratos do Receptor de Insulina , Diferenciação Celular , MicroRNAs/genética , Adipogenia/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-36833797

RESUMO

2,4,6-Trinitrotoluene (TNT), one of the main compounds in ammunition wastewater, is harmful to the environment. In this study, the treatment efficiency of 2,4,6-TNT by different treatment processes, including ferrous ion (Fe2+), hydrogen peroxide (H2O2), Fenton, ultrasound (US) irradiation, US + Fe2+, US + H2O2 and US-Fenton process, was compared. The results showed that US-Fenton was the most effective among all methods studied. The effects of initial pH, reaction time and H2O2 to Fe2+ molar ratio were investigated. The results showed that the removal of TNT, TOC and COD was maximum at an initial pH of 3.0 and H2O2 to Fe2+ molar ratio of 10:1. TNT, TOC and COD removal was fast in the first 30 min, reaching 83%, 57% and 50%, then increased gradually to 99%, 67% and 87% until 300 min, respectively. Semi-batch mode operation increased the removal of TNT and TOC by approximately 5% and 10% at 60 min, respectively. The average carbon oxidation number (ACON) was increased from -1.7 at 30 min to a steady-state value of 0.4, indicating the mineralization of TNT. Based on GC-MS analysis, 1,3,5-trinitrobenzene, 2,4,6-trinitrobenzene acid, 3,5-dinitrobenznamine and 3,5-dinitro-p-toluidine were the major byproducts from the US-Fenton process. The TNT degradation pathway was proposed, which involved methyl group oxidation, decarboxylation, aromatic ring cleavage and hydrolysis.


Assuntos
Trinitrotolueno , Poluentes Químicos da Água , Trinitrotolueno/química , Trinitrotolueno/efeitos da radiação , Peróxido de Hidrogênio/química , Oxirredução , Ferro/química , Águas Residuárias , Poluentes Químicos da Água/química
14.
J Anim Sci Biotechnol ; 14(1): 21, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36732836

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) regulate numerous biological processes, including adipogenesis. Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in livestock, such as the content of intramuscular fat (IMF). However, the significance of lncRNAs in intramuscular adipogenesis remains unclear. This research aimed to reveal the lncRNAs transcriptomic profiles in the process of bovine intramuscular adipogenesis and to identify the lncRNAs involved in the adipogenesis of bovine intramuscular adipocytes. RESULTS: In this research, a landscape of lncRNAs was identified with RNA-seq in bovine intramuscular adipocytes at four adipogenesis stages (0 d, 3 d, 6 d, and 9 d after differentiation). A total of 7035 lncRNAs were detected, including 3396 novel lncRNAs. Based on the results of differential analysis, co-expression analysis, and functional prediction, we focused on the bovine intramuscular adipogenesis-associated long non-coding RNA (BIANCR), a novel lncRNA that may have an important regulatory function. The knockdown of BIANCR inhibited proliferation and promoted apoptosis of intramuscular preadipocytes. Moreover, BIANCR knockdown inhibited intramuscular adipogenesis by regulating the ERK1/2 signaling pathway. CONCLUSION: This study obtained the landscape of lncRNAs during adipogenesis in bovine intramuscular adipocytes. BIANCR plays a crucial role in adipogenesis through the ERK1/2 signaling pathway. The results are noteworthy for improving beef meat quality, molecular breeding, and metabolic disease research.

15.
J Org Chem ; 88(8): 5212-5219, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36273332

RESUMO

Electroreductive ring-opening carboxylation of cycloketone oxime esters with atmospheric carbon dioxide is reported. This reaction proceeded under simple constant current conditions in an undivided cell using glassy carbon as the cathode and magnesium as the sacrificial anode, providing substituted γ- and δ-cyanocarboxylic acids in moderate to good yields. Electrochemically generated cyanoalkyl radicals and cyanoalkyl anion are proposed as the key intermediates.

16.
J Agric Food Chem ; 70(46): 14641-14653, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36373418

RESUMO

Fat deposition significantly impacts the meat yield and the meat quality of beef cattle, which is closely associated with the preadipocyte proliferation and differentiation. Bta-miR-493 is expressed differentially in the backfat of Qinchuan cattle of various ages, and it may be involved in the fat accumulation of beef cattle. However, the role and functional mechanism of bta-miR-493 in fat deposition are still unclear. Tissue-specific expression analysis showed that the level of bta-miR-493 was moderately abundant in the adipose tissues of beef cattle. Moreover, the expression of bta-miR-493 in perirenal fat, subcutaneous fat, and longissimus dorsi muscle of Japanese black cattle was significantly higher than that in Qinchuan cattle. EdU staining, cell counting assay, and Oil Red O staining indicated that bta-miR-493 promoted the proliferation of bovine preadipocytes but inhibited their differentiation. The dual luciferase assay and transcriptomic analysis confirmed that bone morphogenetic protein receptor 1A (BMPR1A) is a target gene of bta-miR-493. Moreover, rescue experiments showed that bta-miR-493 could promote bovine preadipocyte proliferation but inhibit their differentiation by targeting BMPR1A via the TGFß/BMP and p38MAPK signaling pathways. Overall, our findings revealed a bta-miR-493-BMPR1A-TGFß/BMP/p38MAPK regulatory axis that will serve as a theoretical foundation for the molecular breeding of beef cattle with high intramuscular fat deposition.


Assuntos
MicroRNAs , Fator de Crescimento Transformador beta , Bovinos/genética , Animais , Fator de Crescimento Transformador beta/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Diferenciação Celular , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Sistema de Sinalização das MAP Quinases
17.
Int J Biol Macromol ; 220: 33-42, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35944756

RESUMO

Noncoding RNAs, such as long noncoding RNAs (lncRNAs), are abundant in livestock. Many lncRNAs that affect the growth rate of livestock have been identified in muscles. However, some of their physiological functions and regulatory mechanisms remain unclear. In this study, we identified a new lncRNA (lncPRRX1) and investigated its effect on the proliferation of bovine myoblasts. LncPRRX1 was highly expressed in muscle tissue, and interference with lncPRRX1 inhibited the proliferation of bovine myoblasts in vitro. The RNA molecules of lncPRRX1 act on miR-137 as competitive endogenous RNAs (ceRNAs). Overexpression of miR-137 suppressed the proliferation of myoblasts, while inhibition of miR-137 had the opposite effect. In addition, the predicted target genes of miR-137 were significantly enriched in the mitogen-activated protein kinase (MAPK) signaling pathway, in which Cell Division Cycle 42 (CDC42) was shown to be the direct target gene of miR-137, and interference with CDC42 inhibited myoblast proliferation. Furthermore, interference with lncPRRX1 repaired the defects in CDC42 protein levels and cell proliferation caused by miR-137 inhibitors. Our results suggested that lncPRRX1 promoted bovine myoblast proliferation by regulating the miRNA-137/CDC42 axis.


Assuntos
MicroRNAs , RNA Longo não Codificante , Animais , Bovinos , Diferenciação Celular/genética , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mioblastos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/metabolismo
18.
Angew Chem Int Ed Engl ; 61(38): e202207660, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-35862121

RESUMO

Highly selective and direct electroreductive ring-opening carboxylation of epoxides with CO2 in an undivided cell is reported. This reaction shows broad substrate scopes within styrene oxides under mild conditions, providing practical and scalable access to important synthetic intermediate ß-hydroxy acids. Mechanistic studies show that CO2 functions not only as a carboxylative reagent in this reaction but also as a promoter to enable efficient and chemoselective transformation of epoxides under additive-free electrochemical conditions. Cathodically generated α-radical and α-carbanion intermediates lead to the regioselective formation of α-carboxylation products.


Assuntos
Dióxido de Carbono , Hidroxiácidos , Compostos de Epóxi , Estirenos
19.
Genomics ; 114(4): 110416, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35718089

RESUMO

The BBS2 gene plays a vital role in human obesity and fat deposition. However, little is known about it in beef cattle. Therefore, this study investigates the function of BBS2 in the fat deposition of beef cattle and screens the effective SNPs marker for meat quality traits in cattle breeding. The expression of BBS2 is negatively correlated with marbling ratios of beef cattle. Moreover, the knockdown of BBS2 promoted adipogenesis and lipid accumulation of bovine preadipocytes by stimulating PPARγ, FABP4, and FASN expression (P < 0.01). Four novel SNPs in the exons of BBS2 in Chinese Qinchuan cattle were identified and of which the g.24226239C > T (Q527), g.24223562G > A (V441I), and g.24227851A > G (Q627R) were significantly associated with the meat quality of Qinchuan cattle (P < 0.01, P < 0.05). The findings suggested that BBS2 could be used as a candidate gene for meat quality improvement in Qinchuan cattle. Furthermore, these genotypes can be exploited as molecular markers in future beef breeding projects.


Assuntos
Adipogenia , Carne , Adipogenia/genética , Animais , Bovinos/genética , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Análise de Sequência de DNA
20.
Org Lett ; 24(19): 3565-3569, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35532347

RESUMO

Direct electrocarboxylation of various N-acylimines with atmospheric CO2 is achieved in an undivided cell under mild conditions, affording substituted α-amino acids in yields of 62-95%. This reaction is conducted with high efficiency using triethanolamine as an external reductant under nonsacrificial anode conditions, and can be facilely performed on gram scale. Preliminary mechanistic studies including cyclic voltammetry and control experiments support N-radical carbanion as the key intermediate.


Assuntos
Aminoácidos , Dióxido de Carbono , Dióxido de Carbono/química
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