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1.
Small ; : e2406621, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39344540

ABSTRACT

Photo-responsive adsorption has emerged as a vibrant area because it provides a promising route to reduce the energy consumption of the traditional adsorption separation. However, the current methodology to fabricate photo-responsive sorbents is still subject to the photo-deforming molecular units. In this study, a new initiative of photo-dissociated electron-hole pairs is proposed to generate amazing adsorption activity, and prove its feasibility. Employing CuPP [PP = 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin] framework nanosheets compounded with graphene, binary film (BF) sorbents are successfully fabricated. The paradigmatic BF nanostructure brings about efficiently photo-excited electron-hole pairs with durable enough lifetime to meet the needs of microscopic adsorption equilibrium, which ultimately alters the electron density distribution of adsorption surface, and thus markedly modulates the adsorption activity. Therefore, an amazing photo-enhanced adsorption capability for the index gas CO can be gotten. Once exposed to the visible-light at 420 nm, the CO adsorption capacity (0 °C, 1 bar) is risen from 0.23 mmol g-1 in the darkness to 1.66 mmol g-1, changed by + 622%. This is essentially different from majority of current photo-responsive sorbents based on photo-deforming molecular units, of which adsorption capability is only decreased with photo-induction, and the maximum rate of change reported is just -54%.

2.
Plant Cell Environ ; 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39279510

ABSTRACT

Determining the differences in flower hydraulic traits and structural resource allocation among closely related species adapted to low mean annual precipitation (MAP) can provide insight into plant adaptation to arid environments. Here, we measured the maximum flower hydraulic conductance (Kmax-flower), water potential at induction 50% loss of Kmax-flower (P50-flower), flower pressure-volume parameters, dry mass of individual flowers and structural components (vexillum, wings, keels, stamens and sepals) of six Caragana species growing in regions ranging from 110 to 1400 mm MAP. Compared with species from high-MAP environments, those from low-MAP environments presented lower Kmax-flower, more negative P50-flower, osmotic potential at full turgor (πo) and turgor loss points (πtlp), and a greater bulk modulus of elasticity (ε). Consequently, a negative correlation between Kmax-flower (hydraulic efficiency) and P50-flower (hydraulic safety) was observed across Caragana species. Furthermore, the dry masses of individual flowers and structural components (vexillum, wings, keels, stamens and sepals) were greater in the species from the low-MAP environment than in those from the high-MAP environment. These findings suggest that greater flower hydraulic safety and drought tolerance combined with greater structural resource allocation promote drought adaptation in Caragana species to low-MAP environments.

3.
Inorg Chem ; 63(3): 1607-1612, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38194295

ABSTRACT

Solid base catalysts are widely used in the chemical industry owing to their advantages of environmental friendliness and easy separation. However, their application is limited by basic site aggregation and poor stability. In this study, we report the preparation of magnesium (Mg) single-atom catalysts with high activity and stability by a sublimation-trapping strategy. The Mg net was sublimated as Mg vapor at 620 °C, subsequently transported through argon, and finally trapped on the defects of nitrogen-doped carbon derived from metal-organic framework ZIF-8, producing Mg1/NC. Because of the atomically dispersed Mg sites, the obtained Mg1/NC exhibits high catalytic activity and stability for Knoevenagel condensation of benzaldehyde with malononitrile, which is a typical base-catalyzed reaction. The Mg1/NC catalyst achieves a high efficiency with a turnover frequency of 49.6 h-1, which is much better than that of the traditional counterpart MgO/NC (7.7 h-1). In particular, the activity of Mg1/NC shows no decrease after five catalytic cycles, while that of MgO/NC declines due to the instability of basic sites.

4.
J Gastroenterol Hepatol ; 39(8): 1656-1662, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38686620

ABSTRACT

BACKGROUND AND AIM: To identify individuals with metabolic dysfunction-associated steatohepatitis (MASH) or "at-risk" MASH among patients with metabolic dysfunction-associated steatotic liver disease (MASLD), three noninvasive models are available with satisfactory efficiency, which include magnetic resonance imaging [MRI]- AST (MAST), FibroScan-AST (FAST score), and magnetic resonance elastography [MRE] plus FIB-4 (MEFIB). We aimed to evaluate the most accurate approach for diagnosing MASH or "at-risk" MASH. METHODS: We included 108 biopsy-proven MASLD patients who underwent simultaneous assessment of MRE, MRI proton density fat fraction (MRI-PDFF), and FibroScan scans. Compared with the histological diagnosis, we analyzed the AUC of each model and assessed the accuracy. RESULTS: Our study cohort consisted of 64.8% of MASH and 25.9% of "at-risk" MASH. When analyzing the performance of each model for the diagnostic accuracy of MASH, we found that the AUC [95% CI] of MAST was comparable to FAST (0.803 [0.719-0.886] vs 0.799 [0.707-0.891], P = 0.930) and better than MEFIB (0.671 [0.571-0.772], P = 0.005). Similar findings were observed in the "at-risk" MASH patients. The AUCs [95% CI] for MAST, FAST, and MEFIB were 0.810 [0.719-0.900], 0.782 [0.689-0.874], and 0.729 [0.619-0.838], respectively. The models of MAST and FAST had comparable AUCs (P = 0.347), which were statistically significantly higher than that of MEFIB (P = 0.041). Additionally, the cutoffs for diagnosis of MASH were lower than "at-risk" MASH. CONCLUSION: MAST and FAST performed better than MEFIB in diagnosing "at-risk" MASH and MASH using lower cutoff values. Our findings provided evidence for selecting the most accurate noninvasive model to identify patients with MASH or at-risk MASH.


Subject(s)
Elasticity Imaging Techniques , Magnetic Resonance Imaging , Humans , Elasticity Imaging Techniques/methods , Female , Male , Middle Aged , Fatty Liver/diagnostic imaging , Fatty Liver/etiology , Fatty Liver/diagnosis , Predictive Value of Tests , Adult , Aged , Metabolic Diseases/etiology , Metabolic Diseases/diagnosis , Aspartate Aminotransferases/blood , Risk
5.
BMC Pediatr ; 24(1): 484, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39068388

ABSTRACT

OBJECTIVE: The aim of this study is to identify risk factors associated with acute complicated appendicitis (CA) in children aged three years or younger, providing a theoretical foundation for the management and treatment of acute appendicitis (AA). METHODS: A retrospective analysis was conducted on 135 pediatric patients with AA, admitted to the Department of General Surgery at Anhui Children's Hospital between December 2020 and December 2023, who underwent successful surgical treatment. Based on the intraoperative and postoperative pathological findings, patients were categorized into two groups: complicated appendicitis (CA) (n = 97 cases) and uncomplicated appendicitis (UA) (n = 38 cases). Clinical data including gender, age, weight, disease duration, preoperative white blood cell count (WCC), neutrophil granulocyte (NEUT) count, C-reactive protein (CRP) levels, total bilirubin (TBil) levels, procalcitonin (PCT) levels, calprotectin (Cal) levels, preoperative ultrasound results indicating the presence or absence of fecaliths, maximum appendix diameter, and pediatric appendicitis sore (PAS) were collected and analyzed. Comparative analysis was performed to investigate the differences between the groups and identify risk factors of CA. RESULTS: The CA group exhibited significantly higher values in disease duration, CRP levels, PCT, Cal, presence of appendiceal fecaliths, maximum appendix diameter, and PAS compared to the UA group (P < 0.05). Multivariate analysis identified CRP levels, maximum appendix diameter, and PAS as independent risk factors for CA. Specifically, differences in CRP level (OR = 1.045, 95% CI:1.024 ~ 1.067, P < 0.001), PAS (OR = 1.768, 95% CI:1.086 ~ 2.879, P = 0.022), and maximum appendix diameter (OR = 1.860, 95% CI:1.085 ~ 3.191, P = 0.024) were significant. The area under the receiver operating characteristic curve values were 0.6776 for the PAS, 0.7663 for CRP, and 0.5604 for the maximum appendix diameter. CONCLUSION: CRP levels, PAS, and maximum appendix diameter are independent risk factors for CA in children under three years of age. These parameters are valuable for the early diagnosis of CA.


Subject(s)
Appendicitis , Humans , Appendicitis/blood , Appendicitis/surgery , Appendicitis/complications , Appendicitis/diagnosis , Retrospective Studies , Male , Female , Risk Factors , Child, Preschool , Acute Disease , Infant , Appendectomy , C-Reactive Protein/analysis , Leukocyte Count
6.
Chem Biodivers ; 21(2): e202301572, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38145473

ABSTRACT

Two new triterpenoids (1-2), along with six known analogues (3-8) were obtained from the dried whole plant of Leptopus clarkei. Compound 1 is a 3,4-seco-lupane-type triterpenoid, and compound 2 is a phenylpropanoid-conjugated pentacyclic triterpenoid possessing trans-p-coumaroyl unit attached to oleanane-type skeleton. This is the first report on chemical investigation of the L. clarkei, and the triterpenoid derivatives were found in this plant for the first time. The structures of the new compounds were unequivocally elucidated by HRESIMS and 1D/2D NMR data. Additionally, the isolated compounds were evaluated for theircytotoxicities against four cancer cell lines including HepG2, MCF-7, A549 and HeLa. Notably, compound 2 exhibited the most significant antiproliferative activity with IC50 less than 20 µM for four cancer lines.


Subject(s)
Antineoplastic Agents, Phytogenic , Neoplasms , Triterpenes , Humans , Triterpenes/pharmacology , Triterpenes/chemistry , Magnetic Resonance Spectroscopy , Plant Extracts/chemistry , HeLa Cells , Molecular Structure , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Neoplasms/drug therapy
7.
Chem Biodivers ; : e202401514, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39242337

ABSTRACT

The Yellow River Delta possesses lots of characteristic medicinal plants due to its high salinity and high alkaline environment and Limonium sinense is an iconic plant. However, there are very few studies on L. sinense and its chemical constituents have not been investigated in recent ten years. In the present study, the chemical constituents and bioactivities of L. sinense were fully studied for the first time. UPLC-MS/MS method combined with database comparison identified 109 compounds mainly including flavonoids, alkaloids and polyphenols. In addition, the potential bioactivities of L. sinense were considerated as anti-inflammatory, anti-oxidative, anti-tumor, hepatoprotective and hpyerglycemic activities based on these identified compounds and their related literature. Furthermore, four derivatives of 12-oxo-phytodienoic acid and butenolide including two new ones (1 and 2) were isolated from the whole plants of L. sinense. Their structures, including the absolute configurations, were determined by the analysis of comprehensive spectroscopic data. All isolates were evaluated for their anti-inflammatory activity. Compound 1 exhibited moderate anti-inflammatory activity with IC50 value of 37.5 ± 1.2 µM on NO production level.

8.
Small ; 19(48): e2303632, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37541658

ABSTRACT

Covalent organic frameworks (COFs) are one type of porous organic materials linked by covalent bonds. COFs materials exhibit many outstanding characteristics such as high porosity, high chemical and thermal stability, large specific surface area, efficient electron transfer efficiency, and the ability for predesigned structures. These exceptional advantages enable COFs materials to exhibit remarkable performance in photocatalysis. Additionally, the activity of COFs materials as photocatalysts can be significantly upgraded by ion doping and the formation of heterojunctions. This paper summarizes the latest research progress on COF-based materials applied in photocatalytic systems. Initially, typical structures and preparation methods of COFs are analyzed and compared. Moreover, the essential principles of photocatalytic reactions over COFs-based materials and the latest research developments in photocatalytic hydrogen production, CO2 reduction, pollutants elimination, organic transformation, and overall water splitting are indicated. At last, the outlook and challenges of COF-based materials in photocatalysis are discussed. This review is intended to permit instructive guidance for the efficient use of photocatalysis based on COFs in the future.

9.
J Environ Manage ; 329: 116904, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36528943

ABSTRACT

The apparent second-order rate constant with hexavalent ferrate (Fe(VI)) (kFe(VI)) is a key indicator to evaluate the removal efficiency of a molecule by Fe(VI) oxidation. kFe(VI) is often determined by experiment, but such measurements can hardly catch up with the rapid growth of organic compounds (OCs). To address this issue, in this study, a total of 437 experimental second-order kFe(VI) rate constants at a range of conditions (pH and temperature) were used to train four machine learning (ML) algorithms (lasso regression (LR), ridge regression (RR), extreme gradient boosting (XGBoost), and the light gradient boosting machine (LightGBM)). Using the Morgan fingerprint (MF)) of a range of organic compounds (OCs) as the input, the performance of the four algorithms was comprehensively compared with respect to the coefficient of determination (R2) and root-mean-square error (RMSE). It is shown that the RR, XGBoost, and LightGBM models displayed generally acceptable performance kFe(VI) (R2test > 0.7). In addition, the shapely additive explanation (SHAP) and feature importance methods were employed to interpret the XGBoost/LightGBM and RR models, respectively. The results showed that the XGBoost/LightGBM and RR models suggestd pH as the most important predictor and the tree-based models elucidate how electron-donating and electron-withdrawing groups influence the reactivity of the Fe(VI) species. In addition, the RR model share eight common features, including pH, with the two tree-based models. This work provides a fast and acceptable method for predicting kFe(VI) values and can help researchers better understand the degradation behavior of OCs by Fe(VI) oxidation from the perspective of molecular structure.


Subject(s)
Iron , Water Pollutants, Chemical , Kinetics , Iron/chemistry , Oxidation-Reduction , Water , Organic Chemicals , Water Pollutants, Chemical/chemistry
10.
Angew Chem Int Ed Engl ; 62(27): e202304367, 2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37156725

ABSTRACT

The photo-responsive adsorption has emerged as a vibrant area, but its current methodology is limited by the well-defined photochromic units and their molecular deformation driven by photo-stimuli. Herein, a methodology of nondeforming photo-responsiveness is successfully exploited. With the exploiting agent of Cu-TCPP framework assembled on the graphite and strongly interacted with it, the sorbent generates two kinds of adsorption sites, over which the electron density distribution of the graphite layer can be modulated at the c-axis direction, which can further evolve due to photo-stimulated excited states. The excited states are stable enough to meet the timescale of microscopic adsorption equilibrium. Independent of the ultra-low specific surface area of the sorbent (20 m2 g-1 ), the CO adsorption capability can be improved from 0.50 mmol g-1 at the ground state to 1.24 mmol g-1 (0 °C, 1 bar) with the visible light radiation, rather than the photothermal desorption.

11.
Entropy (Basel) ; 24(3)2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35327833

ABSTRACT

Oversampling is the most popular data preprocessing technique. It makes traditional classifiers available for learning from imbalanced data. Through an overall review of oversampling techniques (oversamplers), we find that some of them can be regarded as danger-information-based oversamplers (DIBOs) that create samples near danger areas to make it possible for these positive examples to be correctly classified, and others are safe-information-based oversamplers (SIBOs) that create samples near safe areas to increase the correct rate of predicted positive values. However, DIBOs cause misclassification of too many negative examples in the overlapped areas, and SIBOs cause incorrect classification of too many borderline positive examples. Based on their advantages and disadvantages, a boundary-information-based oversampler (BIBO) is proposed. First, a concept of boundary information that considers safe information and dangerous information at the same time is proposed that makes created samples near decision boundaries. The experimental results show that DIBOs and BIBO perform better than SIBOs on the basic metrics of recall and negative class precision; SIBOs and BIBO perform better than DIBOs on the basic metrics for specificity and positive class precision, and BIBO is better than both of DIBOs and SIBOs in terms of integrated metrics.

12.
Angew Chem Int Ed Engl ; 61(46): e202212732, 2022 Nov 14.
Article in English | MEDLINE | ID: mdl-36151061

ABSTRACT

Light-responsive adsorbents capture significant attention due to their tailorable performance upon light irradiation. The modulation of such adsorbents is mainly based on weak (physical) interactions caused by steric hindrance while tuning strong interaction with target adsorbates is scarce. Here we report smart π-complexation adsorbents, which can adjust the π-complexation of active sites via light irradiation. A typical metal-organic framework, MIL-101-NH2 , was decorated with azobenzene motifs, and Cu+ as π-complexation active sites were introduced subsequently. The reversible light-induced isomerization of azobenzene regulates the surface electrostatic potentials around Cu+ from -0.038 to 0.008 eV, causing shielding and exposure effects. The alteration of CO uptake is achieved up to 54 % via changing light, while that on MIL-101-NH2 is negligible. This study provides a clue for designing target-specific smart materials to meet the practical stimuli-responsive adsorption demands.

13.
Bioorg Chem ; 111: 104886, 2021 06.
Article in English | MEDLINE | ID: mdl-33836342

ABSTRACT

Our present and previous phytochemical investigations on Leptopus lolonum have resulted in the isolation of almost 30 phenylpropanoid-conjugated pentacyclic triterpenoids (PCPTs). During the continuous study on PCPTs, this kind of triterpenoid ester is considered as a natural product with low toxicity because of it's widely distribution in natural plants and edible fruits including kiwi fruit, durian, jujube, pawpaw, apple and pear. In the present work, we report the isolation, structural elucidation and cytotoxic evaluation of four new PCPTs (1-4) which obtained from L. lolonum. In addition, the possible biosynthesis pathway for 28-norlupane triterpenoid and potent effect of phenylpropanoid moiety for increasing the cytotxic effect of triterpenoids were also discussed. Among these compounds, compound 1 exhibited the highest cytotoxic effect on HepG2 cells with IC50 value of 11.87 µM. Further flow cytometry and western blot analysis demonstrated that 1 caused G1 cell cycle arrest by up-regulated the expression of phosphorylated p53 protein in HepG2 cells and induced cell apoptosis via MAPK and Akt pathways. These results emphasized the potential of PCPTs as lead compounds for developing anti-cancer drugs.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , Malpighiales/chemistry , Plant Extracts/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Hep G2 Cells , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , MAP Kinase Signaling System/drug effects , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plants, Medicinal/chemistry , Propanols/chemistry , Propanols/isolation & purification , Propanols/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Structure-Activity Relationship , Triterpenes/chemistry , Triterpenes/isolation & purification , Triterpenes/pharmacology
14.
Bioorg Chem ; 107: 104628, 2021 02.
Article in English | MEDLINE | ID: mdl-33461038

ABSTRACT

Most of Euphorbiaceae plants are considered as folk medicinal plants because of their various pharmacological effects. However, there are eight Leptopus genus plants which belong to Euphorbiaceae have never be investigated. Thus, four Leptopus genus plants were collected to study their chemical constituents and pharmacological activities. In the present work, the cytotoxicities of the extracts of four Leptopus genus plants were evaluated before phytochemical experiments. And nine new phenylpropanoid-conjugated pentacyclic triterpenoids, along with twenty-two known compounds were isolated from the whole plants of Leptopus lolonum. The structures of these new compounds were unequivocally elucidated by HRESIMS and 1D/2D NMR data. All triterpenoids were screened for their cytotoxicities against four cancer cell lines including HepG2, MCF-7, A549 and HeLa. Among these isolates, the triterpenoid with a phenylpropanoid unit showed increasing cytotoxicity on cancer cells, which suggested the importance of the phenylpropanoid moiety.


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Malpighiales/chemistry , Propanols/chemistry , Triterpenes/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Drug Screening Assays, Antitumor , Humans , Magnetic Resonance Spectroscopy , Malpighiales/metabolism , Molecular Conformation , Plant Extracts/chemistry , Plant Leaves/chemistry , Plant Leaves/metabolism , Plants, Medicinal/chemistry , Plants, Medicinal/metabolism , Structure-Activity Relationship , Triterpenes/isolation & purification , Triterpenes/pharmacology
15.
J Cell Mol Med ; 24(18): 11012-11017, 2020 09.
Article in English | MEDLINE | ID: mdl-32744427

ABSTRACT

Traumatic nerve injuries have become a common clinical problem, and axon regeneration is a critical process in the successful functional recovery of the injured nervous system. In this study, we found that peripheral axotomy reduces PTEN expression in adult sensory neurons; however, it did not alter the expression level of PTEN in IB4-positive sensory neurons. Additionally, our results indicate that the artificial inhibition of PTEN markedly promotes adult sensory axon regeneration, including IB4-positive neuronal axon growth. Thus, our results provide strong evidence that PTEN is a prominent repressor of adult sensory axon regeneration, especially in IB4-positive neurons.


Subject(s)
Nerve Regeneration/physiology , Nerve Tissue Proteins/antagonists & inhibitors , Neuronal Outgrowth/physiology , PTEN Phosphohydrolase/antagonists & inhibitors , Phenanthrenes/pharmacology , Plant Lectins/analysis , Sciatic Neuropathy/physiopathology , Sensory Receptor Cells/metabolism , Animals , Cells, Cultured , Down-Regulation/drug effects , Ganglia, Spinal/cytology , Gene Expression Regulation/drug effects , Mice , Mice, Knockout , Nerve Regeneration/drug effects , Nerve Tissue Proteins/biosynthesis , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/genetics , Neuronal Outgrowth/drug effects , PTEN Phosphohydrolase/deficiency , PTEN Phosphohydrolase/physiology , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Sensory Receptor Cells/chemistry , Sensory Receptor Cells/classification , Sensory Receptor Cells/drug effects
16.
J Cell Physiol ; 235(4): 4011-4021, 2020 04.
Article in English | MEDLINE | ID: mdl-31625158

ABSTRACT

The anatomical structure of the mammalian cerebral cortex is the essential foundation for its complex neural activity. This structure is developed by proliferation, differentiation, and migration of neural progenitor cells (NPCs), the fate of which is spatially and temporally regulated by the proper gene. This study was used in utero electroporation and found that the well-known oncogene c-Myc mainly promoted NPCs' proliferation and their transformation into intermediate precursor cells. Furthermore, the obtained results also showed that c-Myc blocked the differentiation of NPCs to postmitotic neurons, and the expression of telomere reverse transcriptase was controlled by c-Myc in the neocortex. These findings indicated c-Myc as a key regulator of the fate of NPCs during the development of the cerebral cortex.


Subject(s)
Cerebral Cortex/growth & development , Neural Stem Cells/cytology , Proto-Oncogene Proteins c-myc/genetics , Stem Cells/cytology , Animals , Cell Differentiation/genetics , Cell Proliferation/genetics , Cerebral Cortex/metabolism , Embryonic Development/genetics , Female , Gene Expression Regulation, Developmental/genetics , Mice , Neural Stem Cells/metabolism , Neurogenesis/genetics , Neurons/cytology , Neurons/metabolism , Pregnancy , Stem Cells/metabolism
17.
J Asian Nat Prod Res ; 22(11): 1006-1010, 2020 Nov.
Article in English | MEDLINE | ID: mdl-31565966

ABSTRACT

Two new steroidal saponins, ß-sitosterol-3-O-α-l-glucopyranoside (3) and ß-sitosterol-3-O-ß-d-glucopyranosyl-(1→6)-ß-d-glucopyranoside (4), were isolated and identified from the bark of Neolamarckia cadamba, along with 13 known compounds. Their structures were established on the basis of spectral data.


Subject(s)
Rubiaceae , Saponins , Molecular Structure
18.
J Cell Physiol ; 234(12): 23053-23065, 2019 12.
Article in English | MEDLINE | ID: mdl-31134625

ABSTRACT

While axon regeneration is a key determinant of functional recovery of the nervous system after injury, it is often poor in the mature nervous system. Influx of extracellular calcium (Ca2+ ) is one of the first phenomena that occur following axonal injury, and calcium/calmodulin-dependent protein kinase II (CaMKII), a target substrate for calcium ions, regulates the status of cytoskeletal proteins such as F-actin. Herein, we found that peripheral axotomy activates CaMKII in dorsal root ganglion (DRG) sensory neurons, and inhibition of CaMKII impairs axon outgrowth in both the peripheral and central nervous systems (PNS and CNS, respectively). Most importantly, we also found that the activation of CaMKII promotes PNS and CNS axon growth, and regulatory effects of CaMKII on axon growth occur via affecting the length of the F-actin. Thus, we believe our findings provide clear evidence that CaMKII is a critical modulator of mammalian axon regeneration.


Subject(s)
Actins/genetics , Calcium-Calmodulin-Dependent Protein Kinase Type 2/genetics , Nerve Regeneration/genetics , Neuronal Outgrowth/genetics , Animals , Axons/metabolism , Axons/pathology , Calcium/metabolism , Central Nervous System/growth & development , Central Nervous System/metabolism , Ganglia, Spinal/growth & development , Ganglia, Spinal/metabolism , Growth Cones/metabolism , Humans , Mice , Peripheral Nerves/growth & development , Peripheral Nerves/pathology , Sensory Receptor Cells/metabolism , Sensory Receptor Cells/pathology
19.
J Cell Physiol ; 234(12): 22517-22528, 2019 12.
Article in English | MEDLINE | ID: mdl-31102288

ABSTRACT

The inflammatory response is a critical regulator for the regeneration of axon following nervous system injury. Nuclear factor-kappa B (NF-κB) is characteristically known for its ubiquitous role in the inflammatory response. However, its functional role in adult mammalian axon growth remains elusive. Here, we found that the NF-κB signaling pathway is activated in adult sensory neurons through peripheral axotomy. Furthermore, inhibition of NF-κB in peripheral sensory neurons attenuated their axon growth in vitro and in vivo. Our results also showed that NF-κB modulated axon growth by repressing the phosphorylation of STAT3. Furthermore, activation of STAT3 significantly promoted adult optic nerve regeneration. Taken together, the findings of our study indicated that NF-κB/STAT3 cascade is a critical regulator of intrinsic axon growth capability in the adult nervous system.


Subject(s)
Axons/physiology , NF-kappa B/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Regeneration/physiology , STAT3 Transcription Factor/metabolism , Animals , Antibodies , Cells, Cultured , Female , Gene Expression Regulation/drug effects , Gene Expression Regulation/physiology , Glyceraldehyde 3-Phosphate/pharmacology , Intracellular Signaling Peptides and Proteins/pharmacology , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , NF-kappa B/antagonists & inhibitors , NF-kappa B/genetics , Optic Nerve , Proline/analogs & derivatives , Proline/pharmacology , Proto-Oncogene Proteins c-myc/genetics , STAT3 Transcription Factor/antagonists & inhibitors , STAT3 Transcription Factor/genetics , Sciatic Nerve , Thiocarbamates/pharmacology
20.
Plant Biotechnol J ; 17(7): 1446-1457, 2019 07.
Article in English | MEDLINE | ID: mdl-30623555

ABSTRACT

In Arabidopsis, the initiation and proliferation of stomatal lineage cells is controlled by SPEECHLESS (SPCH). Phosphorylation of SPCH at the post-translational level has been reported to regulate stomatal development. Here we report that IDD16 acts as a negative regulator for stomatal initiation by directly regulating SPCH transcription. In Arabidopsis, IDD16 overexpression decreased abaxial stomatal density in a dose-dependent manner. Time course analysis revealed that the initiation of stomatal precursor cells in the IDD16-OE plants was severely inhibited. Consistent with these findings, the transcription of SPCH was greatly repressed in the IDD16-OE plants. In contrast, IDD16-RNAi transgenic line resulted in enhanced stomatal density, suggesting that IDD16 is an intrinsic regulator of stomatal development. ChIP analysis indicated that IDD16 could directly bind to the SPCH promoter. Furthermore, Arabidopsis plants overexpressing IDD16 exhibited significantly increased drought tolerance and higher integrated water use efficiency (WUE) due to reduction in leaf transpiration. Collectively, our results established that IDD16 negatively regulates stomatal initiation via trans-repression of SPCH, and thus provide a practical tool for increasing plant WUE through the manipulation of IDD16 expression.


Subject(s)
Arabidopsis Proteins/genetics , Arabidopsis/genetics , Basic Helix-Loop-Helix Transcription Factors/genetics , Gene Expression Regulation, Plant , Plant Stomata/physiology , Arabidopsis/physiology , Droughts
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