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In China, Jiang Fructus aurantii (JFA) has attracted increasing interest as a famous traditional herbal medicine and valuable economic food for its valuable medicinal and industrial properties. In the current work, contrasted with conventional extraction techniques, natural flavonoids from JFA (naringin and neohesperidin) were extracted with remarkable effectiveness utilizing a sustainable deep eutectic solvents combined ultrasonic-assisted extraction (DESs-UAE) protocol. The optimal extraction capacity can be achieved by mixing 30 % water with a molar ratio of 1:3 for choline chloride and ethylene glycol, as opposed to the classical extraction solvents of 95 % ethanol, methanol, and water. Moreover, the DESs-UAE extraction programs were also systematically optimized employing Box-Behnken design (BBD) trials, and the eventual findings suggested that the best parameters were a 27 % water content in DES, a 16 mL/g liquid-solid ratio, a 72 min extraction time, and a 62 °C extraction temperature, along with the corresponding greatest contents of NAR (48.18 mg/g) and NEO (34.50 mg/g), respectively. Notably, by comparison with the pre-optimization data, the optimized DES extraction efficiency of flavonoids is markedly higher. Thereafter, the characterization of the solvents before and after extraction, as well as the differences between the four extraction solvent extracts, were compared using the FT-IR analyses. Furthermore, SEM results suggested that the penetration and erosion abilities of the plant cell wall of DES-1 were stronger than those of the other three traditional solvents, thus allowing more release of flavonoid compounds. In conclusion, the present research develops a straightforward, sustainable, and exceedingly efficient approach for the extraction of bioactive flavonoids from JFA, which has the potential to facilitate the efficient acquisition of active ingredients from TCM.
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Solventes Eutéticos Profundos , Flavonoides , Flavonoides/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Ultrassom , Solventes , Água , Extratos VegetaisRESUMO
Fusarium head blight (FHB) is a devastating fungal disease that poses a significant threat to wheat production, causing substantial yield losses. Understanding the molecular mechanisms of wheat resistance to FHB is crucial for developing effective disease management strategies. This study aimed to investigate the mechanisms of FHB resistance and the patterns of toxin accumulation in three wheat cultivars, Annong8455, Annong1589, and Sumai3, with different levels of resistance, ranging from low to high respectively, under natural field conditions. Samples were taken at three different grain-filling stages (5, 10, and 15 DPA) for gene expression analysis and phenotypic observation. Results found that toxin concentration was inversely correlated with varietal resistance but not correlated with disease phenotypes, indicating that toxin analysis is a more accurate measure of disease status in wheat ears and grains. Transcriptomic data showed that Sumai3 exhibited a stronger immune response during all stages of grain filling by upregulating genes involved in the active destruction of pathogens and removal of toxins. In contrast, Annong1589 showed a passive prevention of the spread of toxins into cells by the upregulation of genes involved in tyramine biosynthesis at the early stage (5 DPA), which may be involved in cell wall strengthening. Our study demonstrates the complexity of FHB resistance in wheat, with cultivars exhibiting unique and overlapping defense mechanisms, and highlights the importance of considering the temporal and spatial dynamics of gene expression in breeding programs for developing more resistant wheat cultivars.
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Fusarium , Transcriptoma , Triticum/genética , Melhoramento Vegetal , Perfilação da Expressão Gênica , Grão Comestível , Mecanismos de DefesaRESUMO
Mn3O4 nanoparticles composed of porous reduced graphene oxide nanosheets (Mn3O4@p-rGO) with enhanced oxidase-like activity were successfully fabricated through an in-situ approach for fast colorimetric detection of ascorbic acid (AA). The residual Mn2+ in the GO suspension of Hummers method was directly reused as the manganese source, improving the atom utilization efficiency. Benefiting from the uniform distribution of Mn3O4 nanoparticles on the surface of p-rGO nanosheets, the nanocomposite exhibited larger surface area, more active sites, and accelerated electron transfer efficiency, which enhanced the oxidase-like activity. Mn3O4@p-rGO nanocomposite efficiently activate dissolved O2 to generate singlet oxygen (1O2), leading to high oxidation capacity toward the substrate 3,3',5,5'-tetramethylbenzidine (TMB) without the extra addition of H2O2. Furthermore, the prominent absorption peak of the blue ox-TMB at 652 nm gradually decreased in the presence of AA, and a facile and fast colorimetric sensor was constructed with a good linear relationship (0.5-80 µM) and low LOD (0.278 µM) toward AA. Owing to the simplicity and excellent stability of the sensing platform, its practical application for AA detection in juices has shown good feasibility and reliability compared with HPLC and the 2, 4-dinitrophenylhydrazine colorimetric method. The oxidase-like Mn3O4@p-rGO provides a versatile platform for applications in food testing and disease diagnosis.
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Nanopartículas , Oxirredutases , Colorimetria , Peróxido de Hidrogênio , Porosidade , Reprodutibilidade dos Testes , Ácido AscórbicoRESUMO
BACKGROUND AND OBJECTIVES: The objective of this study was to examine whether the regional methylation levels at the most distal D4Z4 repeat units (RU) in the 4qA-permissive haplotype were associated with disease severity and progression in facioscapulohumeral muscular dystrophy type 1 (FSHD1). METHODS: This 21-year, retrospective, observational cohort study was conducted at the Fujian Neuromedical Center (FNMC) in China. Methylation levels of the most distal D4Z4 RU, including 10 CpGs, were assessed in all participants by bisulfite sequencing. Patients with FSHD1 were stratified into 4 groups based on methylation percentage quartiles, including LM1 (low methylation), LM2 (low to intermediate methylation), LM3 (intermediate to high methylation), and highest methylation (HM) levels. Patients received evaluations of motor function focusing on lower extremity (LE) progression at baseline and in follow-ups. FSHD clinical score (CS), age-corrected clinical severity scale (ACSS), and modified Rankin scale were used to assess motor function. RESULTS: The methylation levels of the 10 CpGs were significantly lower in all 823 patients with genetically confirmed FSHD1 than in 341 healthy controls (HCs). CpG6 methylation levels could distinguish the following: (1) patients with FSHD1 from HCs; (2) symptomatic from asymptomatic/unaffected patients; (3) patients with LE involvement from those without LE involvement, with AUCs (95% CI) of 0.9684 (0.9584-0.9785), 0.7417 (0.6903-0.7931), and 0.6386 (0.5816-0.6956), respectively. Lower CpG6 methylation levels were correlated with higher CS (r = -0.392), higher ACSS (r = -0.432), and earlier onset age of first-ever muscle weakness (r = 0.297). For the LM1, LM2, LM3, and HM groups, the respective proportions of LE involvement were 52.9%, 44.2%, 36.9%, and 23.4%; and onset ages of LE involvement were 20, 26.5, 25, and 26.5 years. Cox regression analysis-adjusted for sex, age at examination, D4Z4 RU, and 4qA/B haplotype-showed that the LM1, LM2, and LM3 groups (i.e., groups with lower methylation levels) had a higher risk of independent ambulation loss, with HRs (95% CI) of 3.523 (1.565-7.930), 3.356 (1.458-7.727), and 2.956 (1.245-7.020), respectively. DISCUSSION: 4q35 distal D4Z4 hypomethylation is correlated with disease severity and progression to lower extremity involvement.
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Distrofia Muscular Facioescapuloumeral , Humanos , Distrofia Muscular Facioescapuloumeral/genética , Distrofia Muscular Facioescapuloumeral/diagnóstico , Estudos Retrospectivos , Metilação de DNA/genética , Gravidade do PacienteRESUMO
Surface oxidation engineering is an effective strategy to construct nanomaterials with enhanced biocatalytic activity. In this study, a facile one-pot oxidation strategy was proposed to synthesize partially oxidized molybdenum disulfide nanosheets (ox-MoS2 NSs), which exhibit good water solubility and can be used as an excellent peroxidase substitute. Under the oxidation process, Mo-S bonds are partially broke and S atoms are replaced by excess oxygen atoms, and the released abundant heat and gases efficiently expended the interlayer distance and weaken the van der Waals forces between adjacent layers. Porous ox-MoS2 NSs can be easily exfoliated by further sonication, and the nanosheets exhibits excellent water dispersibility and no obvious sediment appear even after store for months. Benefiting from the desirable affinity property with enzyme substrates, optimized electronic structure and prominent electron transfer efficiency, the ox-MoS2 NSs exhibit enhanced peroxidase-mimic activity. Furthermore, the ox-MoS2 NSs catalyzed 3,3',5,5'-tetramethylbenzidine (TMB) oxidation reaction could be inhibited by the redox reaction that take place between glutathione (GSH) as well as the direct interaction between GSH and ox-MoS2 NSs. Thus, a colorimetric sensing platform was constructed for GSH detection with good sensitivity and stability. This work provides a facile strategy for engineering structure of nanomaterials and improving enzyme-mimic performance.
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Molibdênio , Peroxidase , Peroxidase/química , Molibdênio/química , Solubilidade , Peroxidases , Glutationa , Corantes , Água , Peróxido de Hidrogênio/química , ColorimetriaRESUMO
A copper-promoted aerobic oxidative [3+2] cycloaddition reaction for the synthesis of various substituted pyrazoles from N,N-disubstituted hydrazines with alkynoates in the presence of bases is developed. This work involves a direct C(sp3)-H functionalization and the formation of new C-C/C-N bonds. In this strategy, inexpensive and easily available Cu2O serves as the promoter and air acts as the green oxidant. The reaction exhibits the advantages of high atom and step economy, high regioselectivity, and easy operation.
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The efficient and green extraction of bioactive ingredients from natural plants play a vital role in their corresponding drug effects and subsequent studies. Recently, deep eutectic solvents (DESs) have been considered promising new green solvents for efficiently and selectively extracting substances from varied plants. In this work, an environment-friendly DESs-based ultrasonic-assisted extraction (DESs-UAE) procedure was developed for highly efficient and non-polluting extraction of alkaloids from the roots of Stephania tetrandra (ST). A total of fifteen different combinations of DESs, compared with traditional organic solvents (methanol and 95% ethanol) and water, were evaluated for extraction of bioactive alkaloids (FAN and TET) from ST, and the results revealed that DESs system made up of choline chloride and ethylene glycol with mole ratio of 1:2 exhibited the optimal extraction efficiency for alkaloids. Additionally, a four-factor and three-level Box-Behnken design (BBD), a particular pattern of response surface methodology (RSM), was used to optimize extraction conditions. RSM results indicated that the maximum extraction yields of FAN, TET, and TA were attained 7.23, 13.36, 20.59 mg/g, respectively, within extraction temperature of 52 °C, extraction time of 82 min, DES water content of 23% (v/v), and liquid-solid ratio of 23 mL/g. The measured results were consistent with the predicted values. Notably, the optimized DES extraction efficiency of TA, according to the experimental data analysis, is 2.2, 3.3 and 4.1 times higher than methanol, 95% ethanol and water, respectively. Meanwhile, based on 3D response surface plots, interactive effects plots and contour maps, the effects of the aforementioned four essential factors on the extraction yield and their interactions on the response were visualized. The results revealed that the mutual interactions between extraction temperature and liquid-solid ratio exhibited positive effects on all responses, while extraction time and water content in DES posed a negative effect. Therefore, these results suggest that DESs, as a class of novel green solvents, with the potential to substitute organic solvent and water, can be widely and effectively applied to extract bioactive compounds from natural plants.
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Alcaloides , Stephania tetrandra , Solventes Eutéticos Profundos , Metanol , Solventes , Água , Extratos Vegetais , EtanolRESUMO
Eighteen stilbenes (1-18), including six previously undescribed ones (1-6), with diverse modification patterns were isolated from the leaves of edible and medicinal plant Cajanus cajan. Among the new isolates, compounds 1-3 were initially obtained as three racemic mixtures, which were further resolved into three pairs of optically pure enantiomers, respectively, by chiral HPLC. Besides, compounds 8, 10, 11, and 18 were obtained from C. cajan for the first time. The chemical structures and absolute configurations of the new stilbenes were elucidated unambiguously on the basis of extensive spectroscopic analyses, single crystal X-ray crystallographic study, and quantum chemical electronic circular dichroism (ECD) calculations. In addition, the in vitro anti-inflammatory activities of all isolated stilbenes were evaluated. Compounds 2, 9, 10, 11, and 14 exerted moderate suppression of nitric oxide (NO) secretion in lipopolysaccharide (LPS)-induced RAW264.7 cells without exhibiting substantial cytotoxicity.
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Cajanus , Estilbenos , Anti-Inflamatórios/farmacologia , Cajanus/química , Estrutura Molecular , Folhas de Planta/química , Estilbenos/química , Estilbenos/farmacologiaRESUMO
Long non-coding RNA HOX Transcript Antisense RNA (HOTAIR) is overexpressed in multiple cancers with diverse genetic profiles. Importantly, since HOTAIR heavily contributes to cancer progression by promoting tumor growth and metastasis, HOTAIR becomes a potential target for cancer therapy. However, the underlying mechanism leading to HOTAIR deregulation is largely unexplored. Here, we performed a pan-cancer analysis using more than 4,200 samples and found that intragenic exon CpG island (Ex-CGI) was hypermethylated and was positively correlated to HOTAIR expression. Also, we revealed that Ex-CGI methylation promotes HOTAIR expression through enhancing the transcription elongation process. Furthermore, we linked up the aberrant intragenic tri-methylation on H3 at lysine 4 (H3K4me3) and Ex-CGI DNA methylation in promoting transcription elongation of HOTAIR. Targeting the oncogenic CDK7-CDK9-H3K4me3 axis downregulated HOTAIR expression and inhibited cell growth in many cancers. To our knowledge, this is the first time that a positive feedback loop that involved CDK9-mediated phosphorylation of RNA Polymerase II Serine 2 (RNA PolII Ser2), H3K4me3, and intragenic DNA methylation, which induced robust transcriptional elongation and heavily contributed to the upregulation of oncogenic lncRNA in cancer has been demonstrated. Targeting the oncogenic CDK7-CDK9-H3K4me3 axis could be a novel therapy in many cancers through inhibiting the HOTAIR expression.
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Quinase 9 Dependente de Ciclina , Histonas , Neoplasias , RNA Polimerase III , RNA Longo não Codificante , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/metabolismo , Metilação de DNA , Retroalimentação Fisiológica/fisiologia , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , RNA Polimerase III/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
BACKGROUND: Facioscapulohumeral muscular dystrophy type 1 (FSHD1) is a rare disease, which is often underdiagnosed due to its heterogeneous presentations and complex molecular genetic basis, leading to a lack of population-based epidemiology data, especially of prevalence and disease progression. METHODS: Fujian Neuromedical Centre (FNMC) is a diagnosis centre for clinical-genetic FSHD in China, and the only one employing pulsed-field gel electrophoresis (PFGE)-based Southern blotting for all FSHD1 genetic tests. Three sources distributed across all six spatial zones in China, were used to obtain information regarding FSHD1 events, namely, FNMC, Genetic and Myopathy Group (branches of the Neurology Society of the Chinese Medical Association), and "FSHD-China" (an organization supported by FSHD patients). During 2001-2020, all genetically-confirmed FSHD1 from China were registered in FNMC. Follow-up was conducted in the 20-year period to obtain data on disease progression, which was mainly described in terms of independent ambulation loss. FINDINGS: Of the 1,744 FSHD1 genetic tests (total test number 1,802) included in the analysis, 997 (57.2%) patients from 620 families were diagnosed with FSHD1. The estimated prevalence of genetically-confirmed FSHD1 in China is 0.75 per million (95% confidence interval [CI], 0.70-0.79) during 2001-2020, with 0.78 (95% CI, 0.72-0.85) in males and 0.71 (95% CI, 0.65-0.78) in females. The estimated prevalence increased from 0.22 (95% CI, 0.19-0.26) per million in 2001-2015 to 0.53 (95% CI, 0.49-0.57) per million in 2016-2020 (p < 0.001). The prevalence in Fujian province was 7.10 per million, 4.66 per million, and 2.44 per million, during 2001-2020, 2001-2015, and 2016-2020, respectively. Among the 861 symptomatic plus asymptomatic patients of the total 997 patients, the median onset age at first-ever muscle weakness was 16 years of age (range 1-81); the median number of contracted D4Z4 repeats was 5 units (range 1-9); the median 4qA-allele-specific methylation level was 41% (range 14%-69%). Of the 977 symptomatic patients followed-up during 2001-2020, 117 patients (12.0%) lost independent ambulation. The expected duration from onset of first-ever muscle weakness to onset of independent ambulation loss was 40 years. The group with loss of independent ambulation had a smaller number of contracted D4Z4 repeats (p < 0.001) and had an earlier onset age of first-ever muscle weakness (p < 0.001) compared to the group without loss of independent ambulation. INTERPRETATION: Our research captures the largest genetically-confirmed FSHD1 population worldwide, to calculate its prevalence of 0.75 per million in China from 2001 to 2020. Approximately 12.0% of symptomatic plus asymptomatic patients of FSHD1 will lose independent ambulation in 40 years from onset of first-ever muscle weakness. FUNDING: This work has been supported by the grants (U2005201, 81870902, N.W.) and (81974193, 81671237, Z.Q.W.) from the National Natural Science Foundation of China; Joint Funds for the Innovation of Science and Technology of Fujian Province (2018Y9082) (N.W.), and the Key Clinical Specialty Discipline Construction Program of Fujian (N.W.).
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Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common muscular dystrophy. FSHD type 1 (FSHD1) is caused by multicopy contraction of D4Z4 repeats on chromosome 4q35. Human induced pluripotent stem cell (hiPSC) lines serve as important research models for various types of diseases in vitro. Here, we reprogrammed human peripheral blood mononuclear cells (PMBCs) into hiPSCs with episomal plasmid from two FSHD1 patients. These hiPSC lines maintained normal karyotype and exhibited typical morphology. Both of them could express pluripotency markers and differentiate into three layers. The hiPSC lines could be used for screening potential therapeutic targets and mechanism research.
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Células-Tronco Pluripotentes Induzidas , Distrofia Muscular Facioescapuloumeral , Adulto , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares/metabolismo , Distrofia Muscular Facioescapuloumeral/genética , Distrofia Muscular Facioescapuloumeral/metabolismoRESUMO
Acute lung injury (ALI) and its severe form acute respiratory distress syndrome (ARDS) are respiratory failures caused by excessive alveolar inflammation with high mortality. In this study, we investigated the effects of bone marrow mesenchymal stem cells (BMSCs) on lung injury of lipopolysaccharide (LPS)-induced ALI and explored the associated mechanisms. BMSCs were isolated, cultured, identified by staining with CD34 and CD44 surface markers. LPS-induced ALI mouse model was generated by injecting with LPS and divided into ALI group and ALI+BMSCs group. Mice treated without any reagents were assigned as Control, mice transplanted with BMSCs were assigned as BMSCs group. Regulatory T (Treg) and Th17 percentages were evaluated using flow cytometry. Proresolving mediators (resolvin E1 (RvE1), protectin D1 (ProD1)) in lung tissue and cytokines (interleukin-6 (IL-6) and IL-17) in serum were analyzed by ELISA. Myeloperoxidase (MPO) activity was determined. Cultured cells demonstrated typical characteristics of BMSCs. BMSCs transplantation (ALI+BMSCs) obviously alleviated LPS-induced ALI in mice. BMSCs transplantation significantly decreased MPO activity in LPS-induced ALI in mice compared to the Control group (p < 0.05). BMSCs transplantation markedly increased Treg percentages and decreased dendritic cells (DCs) and Th17 cells percentages compared to those of the Control group (p < 0.05). BMSCs transplantation remarkably enhanced RvE1 and ProD1 levels in LPS-induced ALI (ALI+BMSCs) compared to the ALI group (p < 0.05). BMSCs transplantation significantly attenuated IL-6 and IL-17 levels in serum of mice treated with LPS (ALI+BMSCs) compared to those of the ALI group (p < 0.05). In conclusion, BMSCs transplantation effectively attenuated LPS-induced pathological injury of ALI in mice, at least partly through promoting proresolving mediators RvE1 and ProD1 and modulating the balance of Treg/Th17.
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Domestic livestock grazing has caused dramatic changes in plant community composition across the globe. However, the response of plant species abundance in communities subject to grazing has not often been investigated through a functional lens, especially for belowground traits. Grazing directly impacts aboveground plant tissues, but the relationships between above- and belowground traits, and their influence on species abundance are also not well known. We collected plant trait and species relative abundance data in the grazed and nongrazed meadow plant communities in a species-rich subalpine ecosystem of the Qinghai-Tibet Plateau. We measured three aboveground traits (leaf photosynthesis rate, specific leaf area, and maximum height) and five belowground traits (root average diameter, root biomass, specific root length, root tissue density, and specific root area). We tested for shifts in the relationship between species relative abundance and among all measured traits under grazing compared with the nongrazed meadow. We also compared the power of above- and belowground traits to predict species relative abundance. We observed a significant shift from a resource conservation strategy to a resource acquisition strategy. Moreover, this resource conservation versus resource acquisition trade-off can also determine species relative abundance in the grazed and nongrazed plant communities. Specifically, abundant species in the nongrazed meadow had aboveground and belowground traits that are associated with high resource conservation, whereas aboveground and belowground traits that are correlated with high resource acquisition determined species relative abundance in the grazed meadow. However, belowground traits were found to explain more variances in species relative abundance than aboveground traits in the nongrazed meadow, while aboveground and belowground traits had comparable predictive power in the grazed meadow. We show that species relative abundance in both the grazed and the nongrazed meadows can be predicted by both aboveground traits and belowground traits associated with a resource acquisition versus conservation trade-off. More importantly, we show that belowground traits have higher predictive power of species relative abundance than aboveground traits in the nongrazed meadow, whereas in the grazed meadows, above- and belowground traits had comparable high predictive power.
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At present, the pathogenesis of the novel coronavirus disease 2019 (COVID-19) has not been fully elucidated. Clinical and experimental findings from studies investigating COVID-19 have suggested that the immune-inflammatory response has a crucial role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The present article aimed to systematically review the available literature on the pathogenesis of COVID-19. Severe COVID-19 is characterized by organ dysfunction, hypercytokinemia and lymphopenia. It is assumed that the direct cytopathological damage of host cells and the dysregulated immune response caused by SARS-CoV-2 may be the primary underlying mechanisms of COVID-19. Based on the published literature, this review attempts to provide an integrated view of the immunological mechanisms and the potential pathogenesis of COVID-19, providing an in-depth summary of the host-pathogen interaction and host immune responses. It is of great importance to elucidate the possible pathogenesis of COVID-19 to determine the direction of future research.
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A combined strategy of building blocks recognition and molecular network construction, termed the building blocks-based molecular network (BBMN), was first presented to facilitate the efficient discovery of novel natural products. By mapping the BBMN of the total alkaloid fraction of Flueggea suffruticosa, three Securinega alkaloids (SEAs) with unusual chemical architectures, suffranidinesâ A-C (1-3), were discovered and isolated. Compound 1 characterizes an unprecedented 8/5/6/5/6/6/6/6-fused octacyclic scaffold with a unique cage-shaped 3-azatricyclo[6.4.0.03,11 ]dodecane core. Compounds 2 and 3 are highly modified SEA dimers that incorporate additional C6 motifs. A hypothetical biosynthetic pathway for 1-3 was proposed. In addition, 1 significantly induced neuronal differentiation and neurite extension by upregulating eukaryotic elongation factor 2 (eEF2)-mediated protein synthesis.
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Alcaloides/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Euphorbiaceae/química , Securinega/química , Alcaloides/química , Produtos Biológicos/química , Conformação MolecularRESUMO
Four novel stilbene dimers (1-4), together with their biosynthetically related stilbene monomers (5 and 6), were isolated from the leaves of Cajanus cajan. Their structures with absolute configurations were determined by comprehensive analysis of spectroscopic data and electronic circular dichroism calculations. Compounds 1 and 2 are two novel dimeric stilbenes with an unusual coupling pattern that resulted in a rare configurationally stable Csp2-Csp3 chiral axis with both point and axial chirality in their molecules. Due to their unique inherent structural features, both of them naturally occur as equilibrating mixtures of unequally populated atropo-diastereomers and their respective enantiomers. Compounds 3 and 4 are two pairs of novel dimeric stilbene atropisomers featuring a rotationally hindered central biaryl axis. Notably, 3 contains a rare arylbenzoquinone core and 4 is a symmetric dimer with a C2 symmetry axis. The hypothetical biosynthetic pathway of 1-4 was also proposed herein. All the new compounds exhibited significant protein tyrosine phosphatase-1B (PTP1B) inhibition effects. In addition, the preliminary mode of action for the most potent compound 3 was investigated by molecular docking and binding free energy calculation.
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Cajanus , Estilbenos , Simulação de Acoplamento Molecular , Estrutura Molecular , Folhas de Planta , EstereoisomerismoRESUMO
The anterior cruciate ligament and medial collateral ligament are important static stabilizers of the knee. The patellar tendon is part of the knee extensor mechanism. The injury simultaneously involving these three structures is very rare. This paper reports a case with simultaneous ipsilateral rupture of the anterior cruciate ligament, medial collateral ligament, patellar tendon, and an occult compression fracture of the posterolateral tibial plateau. This injury pattern has not been reported in literature yet. The injury mechanism was hypothesized as a sudden anterior translation and valgus of the proximal tibia when the knee was in high flexion, followed by an eccentric quadriceps' contracture. In the followed management, ruptured medial collateral ligament and patellar tendon were sutured with augment, while the torn anterior cruciate ligament and fracture were treated conservatively. The outcome of the treatment was satisfactory, and no complication was observed. To this combined injury, a comprehensive consideration, including physical examination, multiple imaging examinations, and analysis of injury mechanism, is essential for a full diagnosis and treatment decision. Especially, computed tomography may help to identify an occult or non-displaced fracture, which would be easily misdiagnosed when nothing unusual was found in routine X-rays. In the treatment, it is suggested to perform a selective or step-by-step repair to the damaged structures, rather than an immediate total repair after injury.
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To aim of the present paper was to introduce a novel fixation technique for the treatment of inferior pole fracture of the patella. We performed a prospective observational study of consecutive cases of inferior pole fracture of the patella that were treated at our institution between January 2018 and June 2019. The patients include three men and one woman, with an average age of 47 years (range: 42-59 years). All patients were treated with the novel rim plating fixation technique for preserving the inferior pole of the patella. During the surgery, a 2.4 mm straight locking compression plate was contoured to adapt to the arc of the lower half of the patella as the rim plate. After reduction of the fracture, the rim plate was fixed to the proximal fragment of the patella through multiple locking screws, against the continuous pull of the patellar tendon. The rim plate encircles and constricts the inferior pole fragments, functioning as a compression and blocking construct. If necessary, an additional anterior tension band or mini locking plate can be used to further prevent anterior displacement of the inferior pole fragments. Under this rigid fixation, motion of the knee and full weight-bearing were encouraged postoperatively. The patients were followed up monthly until 12 months after surgery. The time to achieve 90°pain-free, full range of motion of the knee, and fracture healing, were recorded. Related complications were monitored, including infection, loss of reduction, fixation failure, anterior knee pain, and soft-tissue irritation. The modified Cincinnati knee rating system was used for knee function assessment. The average operative time was 58.8 min (range: 52-63 min). The average blood loss was 59.8 mL (range: 45-71 mL). For all patients, pain-free 90° range of motion was restored in 2-4 weeks, and the full range of motion was restored in 8-11 weeks. All patients achieved bone union in 6-9 weeks with no displacement of the fragments or breakage of the implant. No patient complained of anterior knee pain or soft-tissue irritation. The modified Cincinnati score at 12-month follow up demonstrated excellent outcomes in all four patients. The rim plating technique may be a feasible option for the treatment of the inferior pole fracture of the patella.
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Placas Ósseas , Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Patela/lesões , Patela/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos ProspectivosRESUMO
OBJECTIVE: At present, cephalomedullary nail is the most frequently used implant in the management of intertrochanteric fractures around the world. The implant design and fixation techniques of the cephalomedullary nail have been continuously improved to ensure uncomplicated bone union during the past decade. However, a degree of reduction loss during bone healing is still not rare in clinical work. Many attributed this complication to misoperation during the surgery and hold that a series of techniques and tips could help to avoid the loss of reduction. However, until now there has been no research to explore whether the reduction loss after the operation can be fully prevented in the best cases. The purposes of the study are as follows: (i) to evaluate the efficiency of the current established CMN techniques; (ii) to quantify the loss of reduction under an appropriately implanted CMN to anatomically realigned intertrochanteric fractures; and (iii) to explore the possible underlying causes for the inevitable loss of reduction. METHODS: In the retrospective study, 163 consecutive cases with the intertrochanteric fractures fixed with standard cephalomedullary nail technique were reviewed. The anatomical reduction and optimal positioning of the nail were confirmed by postoperative imaging. The fracture types ranged from 31-A1.1-2.3 according to the OTA/AO fracture classification. One hundred and fifteen cases with stable fracture types (31A1.1-2.1) were allocated to Group A, and 48 cases with unstable 31A2.2-2.3 fracture types were allocated to Group B. The radiological measurements included femoral neck shortening, loss of the neck-shaft angle, cutout, and cut-through of the blade. The outcomes between postoperative and 1 year after the operation were evaluated and compared. RESULTS: The patients consisted of 66 males and 97 females with an average age of 69.4 (range: 46-78, SD: 14.6) years. At the 1-year follow-up, no fixation failure or nonunion was observed in each group. The mean femoral neck shortening and loss of the neck-shaft angle were 4.47 mm (range: 0.43-17.68, SD: 3.71) and 5.4° (range: 0.51-19.10, SD: 3.58) separately. The mean cutout and cut-through were 1.84 mm (range: 0.24-11.30, SD: 2.33) and 1.25 mm (range: 0.51-10.29, SD: 1.74). The average femoral neck shortening and loss of the neck-shaft angle were higher in Group B than Group A. Among the 23 cases with the femoral neck shortening more than 10 mm, 19 cases (16.5%) were from Group A and four cases (8.3%) were from Group B. There were nine (7.8%) cases with the loss of the neck-shaft angle more than 10° in Group A and six (12.5%) cases in Group B. CONCLUSIONS: Current established CMN techniques are efficient in treating intertrochanteric femoral fracture. However, even with currently consensual techniques of cephalomedullary nail, the process of fracture healing still risks the loss of reduction, although the migration of the blade could be minimized. This situation may associate with the intrinsic design of the CMN and further improvement is still needed.